CLS User Manual CHRocodile Compact

CHRocodile%20Compact%20User%20Manual

User Manual:

Open the PDF directly: View PDF .
Page Count: 63

Download
Open PDF In Browser	View PDF

CHRocodile C
Compact sensor for non-contact distance and thickness measurement

Operation Manual

Imprint
This documentation is under the copyright of Precitec Optronik GmbH.
It may not be reproduced or used in a manner contrary to the company’s legal interests without prior
written approval of Precitec Optronik GmbH. It is strictly intended for use in the context of service
operations. Any other use is impermissible. Any sharing of this documentation with third parties
requires the prior, expressed written approval of Precitec Optronik GmbH.
Changes in the technical details from the descriptions, data and figures in this documentation are
reserved.
Printed in the Federal Republic of Germany.
Responsible for Contents
Original Edition
Precitec Optronik GmbH
Schleussnerstrasse 54
63263 Neu-Isenburg / Germany
Telephone:
0049 (0)6102 / 36 76 – 100
Telefax:
0049 (0)6102 / 36 76 – 126
e-mail:
info@precitec-optronik.de
Website:
http://www.precitec.de/en/precitec-group-start-page/
Representatives
Please visit our website to know the current addresses of our representatives.
PRECITEC OPTRONIK's regional contacts for the Optical Measuring Technology can be found here:
http://www.precitec.de/en/contact/precitec-worldwide/

Version Control

Version –
Manual
1.0.0.0

Date

Type of Change

2016/09/20 Original edition

Table of Contents
Table of Contents ........................................................................................................... 4
Basic Safety Instructions ................................................................................................ 7
1.1

Warranty and Liability ...................................................................................... 7

1.2

Safety Symbols .................................................................................................. 7

1.3

Proper Use ......................................................................................................... 8

1.4

Duty of Operator and Personnel....................................................................... 9

1.5

Safety Measurements in Normal Operation ..................................................... 9

1.5.1

Protection from Electronic Shock ............................................................................................ 9

1.5.2

Protection from Optic Radiation / Eye Safety ....................................................................... 9

1.5.3

Grounding the device ............................................................................................................. 10

1.6

Medical or safety-relevant usage ................................................................... 10

1.7

Storage and Transport .................................................................................... 10

1.8

Emergency Procedures ................................................................................... 10

Product Description ....................................................................................................... 11
2.2

General Description ......................................................................................... 11

2.3

Measuring principle ..........................................................................................12

2.3.1

Optical principle ..................................................................................................................... 12

2.4

Sensor Functionalities ......................................................................................14

2.5

Typical applications (Overview) ......................................................................16

2.6

List of Deliverables .......................................................................................... 17

2.7

Connections and Interfaces ............................................................................ 18

2.7.1

Power supply jack ................................................................................................................... 18

2.7.2

Ethernet connector ................................................................................................................. 18
4

2.7.3

Trigger Input/Output and RS422 serial communication ...................................................... 18

2.7.4

External analogue converter box connection .......................................................................20

2.7.5

Status LED ................................................................................................................................ 21

2.8

Sensor Characteristics .................................................................................... 22

2.8.1

Sensor unit characteristics ..................................................................................................... 22

2.8.2

Optical probes characteristics ............................................................................................... 23

2.9

Optical Head Specifications definitions ......................................................... 24

2.10 CHRocodile C performance specifications: ................................................... 26
Operational Start up ..................................................................................................... 28
3.1

Connections and Interfaces ............................................................................ 28

3.2

CHRocodile Explorer and Drivers installations .............................................. 30

3.3

Communication with CHRocodile C................................................................ 30

Measurements Start Up ................................................................................................ 32
4.1

Calibration Table ............................................................................................ 32

4.2

Dark Acquisition .............................................................................................. 32

4.3

Mechanical interfacing ................................................................................... 33

4.4

Basic Settings Configuration ........................................................................... 34

4.5

Data measurement Training ........................................................................... 35

Appendix 1: Advanced Configuration .......................................................................... 37
1. Commands List.................................................................................................... 37
2. Detailed Commands Description ........................................................................ 42
2.1

CTN Command ........................................................................................................................ 42

2.2

DRK Command ........................................................................................................................ 42

2.3

ENC Command ........................................................................................................................ 42

2.4

ETR Command ........................................................................................................................ 43

2.5

IPCN Command ....................................................................................................................... 52
5

2.6

LAI Command .......................................................................................................................... 52

2.7

NOP Command ........................................................................................................................ 53

2.8

SCA Command ......................................................................................................................... 53

2.9

SEN / SENX Command ............................................................................................................ 53

2.10

SHZ Command ......................................................................................................................... 54

2.11

SODX Command ...................................................................................................................... 55

2.12

SSU Command .........................................................................................................................60

2.13

STA Command .........................................................................................................................60

2.14

STO Command ........................................................................................................................ 61

2.15

THR Command ........................................................................................................................ 61

2.16

TRE Command ........................................................................................................................ 62

2.17

TRG Command ........................................................................................................................ 62

2.18

VER Command ........................................................................................................................ 63

Appendix 2: Mechanical Plans ...................................................................................... 64
1. Optical probe mechanical plans ........................................................................ 64
2. CHRocodile C unit mechanical plans ................................................................. 66
3. CHRocodile C unit mechanical interface plans ................................................. 67
Appendix 3: Trouble Shooting ...................................................................................... 68
1.1 Power off ............................................................................................................ 68
1.2 Communication error: ........................................................................................ 68
1.3 Distance Measurement: ...................................................................................... 68
1.4 Thickness measurement: ................................................................................... 69
Appendix 4: Technical support .................................................................................... 70

Basic Safety Instructions
This operation manual contains the most important instructions for the safe operation of the product.

Observe all instructions and guidelines in this documentation.
Moreover, the locally applicable regulations and codes for accident
prevention at the use site must be observed.

1.1 Warranty and Liability
The general terms and conditions of delivery for products and services in the electronics industry
along with the amendments and restrictions deriving from the general terms and conditions of delivery
for Precitec Optronik GmbH apply to all of our products.
We reserve the right to make any changes to the device’s construction for reasons of improving quality
or expanding the possible applications as well as any made for production-related reasons.
Dismantling the device voids all warranty claims. The exception to this is the replacement of parts that
are subject to wear and tear and require maintenance or calibration, to the extent that these are
expressly identified in this documentation.
Changes made to the device on own authority render liability claims void.

1.2 Safety Symbols
The following terms and symbols for hazards and instructions are used in the operation manual.

WARNING
This symbol indicates a possibly dangerous situation. Failure to heed
these instructions can result in minor injuries or cause property damage.
WARNING
High voltage hazard – indicates a hazard from electrical shock and
warns of immediate or impending danger to the life and health of
persons or of extensive property damage.

WARNING
Do not touch – indicates that touching the contact/optics surface can
cause damage/destruction of the component.

IMPORTANT
Information which the user must pay attention to/ be aware of in order to
avoid disruptions in the course of processing/ in product use.
TIP
Provides information that the user needs in order to achieve the
intended result of an action most directly and without difficulty.
PREREQUISITE
Describes all components as well as all conditions that must be present/
be fulfilled in order to the action to be successfully completed.
ADDITIONAL INFORMATION
Informs the user whenever there is additional information about a
context being described.

1.3 Proper Use
The optical sensor is intended as a stand-alone device or as part of a measurement apparatus for
measuring distance, thickness and surfaces for quality and dimensional control.
Only use the optical sensor in a dry environment. The device may only be operated within the
specifications given in the technical data.

Any use deviating from the intended and proper use is considered
improper. The user assumes liability for the consequences in these
cases.

Electromagnetic
Compatibility (EMC)

Both as an individual device and in combination with the devices
designated in this documentation, the optical sensor fulfils the
requirements of the standards DIN EN 61326-1:2013-07 and DIN EN
61010-1:2011-07, and therefore corresponds to the EU-Directive
2014/35/EU and 2014/30/EU. This declaration is valid for all units with
the CE label on it, and it loses its validity if a modification is done on
the product.
When customer-supplied devices or cables are used this can mean
that these Norms may not be fulfilled. For this reason, you should only
8

use the original devices and replacement parts and observe the
instructions for EMC-compliant installation in the handbooks that
come with them.
If the optical sensor is operated inside a facility with other devices, the
entire facility must comply with the provisions in the EC-Guidelines in
the demands of the general operating permit.

1.4 Duty of Operator and Personnel
The operator of the device is obligated only to allow persons to work on the device who:
 are familiar with the basic regulations concerning workplace safety and accident prevention and
who have been instructed in the operation of the device
 have read and understood the safety chapter of this operation manual and have confirmed this with
their signature.
The personnel must be trained in compliance with the regulations and safety instructions and must
have been informed of possible hazards.

1.5 Safety Measurements in Normal Operation
When it is assumed that the device can no longer be operated safety, the device or the plant must be
taken out of operation. The device must be secured against unintended use. Unauthorized
interventions will void your rights to assert warranty claims.
Any attempt to copy or analyze the software will lead without fail to the voiding of all rights to assert
warranty claims.

1.5.1 Protection from Electronic Shock
Please make sure that the live components are uncovered after
opening the housing or removing components. Touching these
components presents a potentially lethal hazard.
When service- and repair work is performed on opened devices and
modules, the main power supply must be reliably shut off (mains cable
unplugged).

1.5.2 Protection from Optic Radiation / Eye Safety
When performing service and maintenance work, make sure that you
9

do not look directly into the LED’s light. The light can harm your eyes.

1.5.3 Grounding the device
Make sure that the device is grounded in compliance with
regulations. Please make sure that the optical sensor is supplied
with power via a grounded main power input line (cold device
plug).

1.6 Medical or safety-relevant usage
If the CHRocodile Line Sensor is used in medical or safety-relevant
applications, the operator must ensure that the CHRocodile Line
Sensor is qualified for the specific application. This includes the
optical characteristics of the measured sample as well as the
influence of temperature and vibrations to the CHRocodile sensor.
Furthermore the user has to check the CHRocodile Line Sensor for
correct measurements and for exceeding the specified measuring
uncertainty.

1.7 Storage and Transport
In order to avoid damages in storage and transport, the following ground rules are to be observed:
 Maintain the storage temperature range allowed in the technical specifications
 Take suitable measures to avoid any damage from humidity or moisture, vibrations or impact
 Do not store in or near magnetic fields (e.g. permanent magnet or alternating electrical field)

1.8 Emergency Procedures
 Disconnect the plant from the main power supply
 Extinguish any flames with a Class B fire extinguisher

Product Description
2.2 General Description
The CHRocodile C is a single-point compact optical sensor dedicated to non-contact surface
measurement. This sensor is based on confocal chromatic principle and offers high precision distance
and thickness measurement.
The CHRocodile C has an original architecture, with no optical fibers, which consists in all elements
embedded in one optoelectronic unit. PRECITEC is the first company to propose this unique
architecture for confocal chromatic sensor, which allows to overcome the device integrating
constraints met in industrial environment.
With its robust and integrated design, the CHRocodile C is ideally suited for industrial inline use and
easily integrable into any kind of inspection machine.
The CHRocodile C can accommodate different types of optical probes. The optical probes
interchangeability is straight forward, as the operator just need to exchange optical probes and move
to the right calibration table. Finally, data transmission is carried out by Ethernet communication up to
4000 measurements per seconds. CHRocodile C characterisctics are described in Section 2.7.
The extraordinary high dynamic range and the outstanding signal-to-noise ratio of the CHRocodile
sensors ensure the best measuring results on any kind of surfaces.
Thanks to its compact dimensions and excellent performance/price ratio, CHRocodile C is the ideal
alternative to classical laser triangulation sensors.

Fig 2-1: CHRocodile C 3D view:

2.3 Measuring principle
2.3.1 Optical principle
For most industrial applications the chromatically coded distance detection method turned out to be
very well suited. CHRocodile C is based on this method and more precisely on the Confocal
Chromatic principle. This principle combines the properties of confocality and axial chromatism.
Axial Chromatism:
That method takes advantage from a lens optical error commonly known as axial chromatic aberration:
the axial position of the focal point depends on the wavelength (color) of the light to be focused. For
example, in the visible spectral range, the focal distance for blue light is shorter than for red light. The
focal points of intermediate wavelengths are located in between according to a continuous axial
position variation. Thus, considering white light passing through an optical objective provided with
axial chromatic aberration, a continuum of color along the optical axis is generated, as an axial
rainbow.
Confocality:
That method also takes advantage from confocal opto-mechanical configuration. A confocal optical
system uses illumination point source and a pinhole in an optically conjugate plane in front of the
detecting system to eliminate out-of-focus signal. As only in focus light can be detected, the image's
optical lateral and axial resolution is improved. Consequently the pinhole act as a spatial filter which
block light which is out of focus or light which come from an external light source.
Confocal Chromatic Imaging:
Considering both confocality and axial chromatism properties, a white light illumination point is imaged
through the chromatic objective on a target object. Depending on the distance of the target from the
focusing chromatic objective, light of just a very narrow wavelength bandwidth is perfectly focused on
the target’s surface. All other spectral components of the light source are out of focus. In the back
path, from the target’s surface to the detector, the reflected light passes through the chromatic
objective, the optically conjugate pinhole which is in front of the spectrometer. The pinhole filters all
wavelengths except the narrow bandwidth which is in focus. The spectrometer analyses the spectrum
of the light reflected back by the target’s surface, and only a chromatic peak is observed
corresponding to the narrow wavelength bandwidth perfectly in focus. The analysis and the barycenter
calculation of this chromatic peak allow to determine the distance of the target surface from the
chromatic objective. (Cf. Fig. 2.2)

Fig. 2-2: Chromatic Confocal Imaging principle (point sensor)

2.4 Sensor Functionalities
The CHRocodile C can transmit two different data: distance and thickness measurements. The
principle of these two applications are explained hereafter.
Chromatic distance measurement

Application type 1

Topographic, profile or roughness measurements are performed with
distance data measurement. With single-point sensors, i.e. CHRocodile
C, one spot is focused on the surface of the measured object using an
optic with a known chromatic aberration. The reflected light is more
intense for the wavelength in focus on the surface. Reflected light is
spectrally analyzed and the spectral response is a peak centered on
focused wavelengths. The spectral peak positions determine the distance
to the surface information. The distance is calculated and transmitted to
host computer at up to 4KHz frequency See Fig. 2-3.

Intensity
Spectral signal

Chromatic
optical probe

Target

Fig. 2-3: Chromatic measurement principle, distance measurement

Chromatic thickness measurement

Application type 2

Thickness measurements can be performed when thickness data is
selected. If a transparent material is within the measurement volume of
the chromatic optical probe, the white light spot is focused on both the
two surfaces of the measured object. The reflected light is more intense
for the two wavelengths in focus on the two surfaces. Reflected light is
spectrally analyzed and the spectral response is constituted of two peaks
centered on focused wavelengths. Considering the refractive index of the
object, one can determine the thickness of the object at the spot light
location. This thickness data is calculated and transmitted to host
computer at up to 4KHz frequency. See Fig. 2-4.

Intensity
Spectral signal

Chromatic
optical probe

Target

Fig. 2-4: Chromatic measurement principle, thickness measurement

2.5 Typical applications (Overview)
A broad range of possible applications is available to this highly precise sensor.
The CHRocodile C is the most compact sensor based on confocal chromatic imaging principle. This
sensor is perfectly suitable for demanding measuring tasks, like non-contact measurement of
microtopography, layer thickness measurements. It could be used both on various reflecting and
scattering surfaces.
The PRECITEC confocal chromatic compact sensor is very well adapted to industrial environment, as
no optical cable are connected to the CHRocodile C unit. The absence of optical cables, promotes
robustness and compactness of the measuring device, and also facilitates the integration and use on
a motorized moving system, such as a coordinate measuring machine (CMM). Then this new type of
sensor overcomes the industrial constraints induced by fiber optic cables that are known to deteriorate
when the measuring device is subject to high accelerations and / or rotational movements.
The CHRocodile C offers the ability to perform fast and accurate metrological control of production, by
being built on automatic or semi-automatic inspection machines, or by being directly integrated on
production line for 100% inspection of manufactured parts. In this, this new technology fully meets the
current needs of the industry as it is suitable for many applications:
-

The measurement of wafer in the field of semiconductor and generally microelectronics,
The measurement and online control of mechanical or optical parts,
Or even the measurement and control of glass or plastic film thickness.

Other fields of applications exist, the common point is to seek a cost effective measurement system
going, more and more compact, as flexible as possible, and highly accurate. It is the case in laboratory
environment and even more in industrial environment. It appears clearly here that the CHRocodile C
unit of measurement meet these different needs.
Optical Head
Application
Electronics

Probe

200µm

1mm

4mm

10mm

















Flatness





Roughness





Plastic and glass thickness



Thin film thickness





Coating thickness





Micro-Electronics
Mechanics
Micro-Mechanics
Optics
Micro-Optics
Shape

Table 2.1:

Sensor applications
16

2.6 List of Deliverables
-

One operational confocal chromatic unit (see Fig. 2-5),
One operational optical probe (see Fig. 2-6),
Power Supply Adapter (100-240VAC to 24VDC +/-10%),
Ethernet cable,
A CD with DLL and firmware,
Software user guide,
Operation Manual,
Calibration report.

Fig 2-5: CHRocodile C unit 3D view:

Fig 2-6: Optical Head 3D view:

a- 0.2mm

b- 1mm c- 4mm d- 10mm

2.7 Connections and Interfaces
All of the connection ports for the sensor unit are located at the rear of the system (see Fig 2-7):

1. Power supply jack,
2. Ethernet interface, RJ45 port
3. 9-PINS Multipoint interface connector (Trigger / Serial communication)
4. 8-PINS round connector (analog converter module connection)

Fig. 2-7: CHRocodile C rear panel: Connections

2.7.1 Power supply jack
The CHRocodile C has two pluggable screw terminal for power supply with 24VDC +/-10%.
Connect the set of power cable supply associated to the Power Supply Adapter (100-240VAC to
24VDC +/-10%) delivered with the CHRocodile C unit.

2.7.2 Ethernet connector
The CHRocodile C has a RJ45 standard connector for Ethernet communication.
Connect the isolated RJ45 standard connector from the CHRocodile C unit to an Ethernet network
(PC). Ethernet supports the data transfer and can also be used for setting configuration by using $
command protocol (Cf. command SODX in Appendix 1), or for loading Calibration Table (Cf. command
TABL in Appendix 1). Ethernet communication allows to transmit a maximum of 16 data values at 4
KHz.

2.7.3 Trigger Input/Output and RS422 serial communication
The Trigger input/output use a multipoint connector interface (9 pins). This connector is used for
trigger Input / Output and for RS422 serial communication (Cf. Table 2-2 and Table 2-3).
The trigger options make the lighting cycle externally controllable and the synchronization between
e.g. a scanning system cycle and the CHRocodile C measurement rate. This means that external
triggering is possible for every measurement up to the full measurement rate of 4000Hz.
18

The interface contains the connection points for the synchronization and RS422 or RS232 serial
communication.
The serial RS232/RS422 is interfaced on the multipoint connector interface (9 pins). Serial
communication are mostly used for sending command as a hyper-terminal, and can also support data
transfer. The maximum transfer rate RS232/RS422 is 1843200 Bd.
PIN

SIGNAL

RS232 TX / RS422 TX-

RS232 RTS / RS422 TX+

RS232 CTS / RS422 RX-

RS232 RX / RS422 RX+

GND

Sync In

Sync Out

Reserve

GND

Table 2.2: Multipoint connector PIN / Signal correspondence

Signal

Function

Description

RS422

RS422
Interface

RS422 (differential signaling) Interface, internally terminated,
no handshaking

RS232

RS232
interface

RS232 interface, RTS/CTS handshaking possible

Sync In

Sync. Input

Positive slope from 0V to 5-24V causes according to the
settings of the sensor:


starts the continuous measurement, if the command
wait for trigger was received first (TRG Command)



starts the single measurement in mode trigger each
(TRE Command)

When in TRW mode, a positive slope starts continuous
measuring, a negative slope stops the measurement
the input has an internal 10 kΩ pullup-resistor to 5 V.
Sync Out

Sync. Output

Sync Output
Positive slope 0 V to 5 V with the start of each measurement.
Table 2.3: Interface
19

Remark: As the Sync-input has a weak pull-up to 5V, your trigger source definitely needs to be able to
sink that current in order to pull the input down to Gnd. So as a trigger source, you can use an open
collector transistor output, that pulls to ground or a push pull output. The input can support 24V, but
the trigger threshold is always at approximately 2V. The trigger occurs on the rising edge, that means
when the external pulldown transistor releases the input or when the pushpull drives to 5V.

Wait for trigger – signal characteristics to Analog Out
The sensor stops after the current data telegram is transmitted and
goes into a standby mode.
The last transmitted analog value persists until the next exposure
(also see TRG command).

2.7.4 External analogue converter box connection
The 8 pins round connector is used for external analogue converter box connection. This option can
be added to the CHRocodile C in order to obtain an analogue output. Also it is possible to add up to 2
encoder-input using this external analogue converter box connection.
The incremental encoder-input makes it possible to precisely assign the measurement point and axis
position without additional hardware. The CHRocodile C can manage with 2-axis encoders if the
optional analogue converter box is connected to the CHRocodile C 8-pins mini-DIN connector.
For an exact distance measurement it is necessary for every measurement value to be assigned to the
exactly correct spatial coordinates. This data must be recorded in the system and transferred to the
evaluation processing unit over the internal interface. To accomplish this, the sensor must be
equipped with the analogue box accessory.

2.7.5 Status LED
LED status / CHRocodile C Status

Power OFF
Power ON, Firmware boot failure
Power ON, Firmware is configured / Continuous measurement
(blink) Power ON, Triggering session (1)
Power ON, Waiting for trigger
(1)

green when triggered at high frequency

No signal
(blink) Saturated intensity signal
High intensity signal
Optimal intensity signal
Medium intensity signal
Low intensity signal

No signal
(blink) Out of range : too far
Far Range
Mid Range
Near Range
(blink) Out of range : too close

Table 2.4: Status LED during functioning
21

2.8 Sensor Characteristics
2.8.1 Sensor unit characteristics
Optical sensor
Measuring principle (1)
Measuring data

(1)

Light source
Dimensions (sensor unit)
Weight

Confocal Chromatic
Distance, Thickness (1)
LED
99.3 x 65 x 47 mm (L x W x H) (2)
425g

Data Transmission
Measurements / second
Interfaces
Transfer rate
Synchronization with ext. devices
Encoder-inputs
SDK

Up to 4000 Hz
Ethernet, RS422, external analogue converter box as accessory
Ethernet (100Mbits); RS422 (9600 – 921600 Baud)
Trigger-input / Output (TTL)
Optional: 2 encoders input available through analogue converter box accessory
DLL written in C, C++ / SDK written in C# with .NET framework 4

Windows XP, Windows 7, Windows 8

Data processing / calculation

Embedded processing unit

Standard to be met
Supply voltage
Rated power
Operating temperature
Storage temperature

24VDC +/-10% with separate main supply unit 100 to 240VAC – 50Hz to 60Hz
4W
0 °C to +50 °C
-20°C to +70°C

CE marking / EMC

Compliant with applicable regulation

RoHS

Compliant with applicable regulation

Protection class

IP50 (DIN 40050/ IEC 144)

Metrological specifications
Axial resolution / Repeatability (3) (4)

3x10-5 x Measuring Range

Accuracy (4)

2x10-4 x Measuring Range

Optical probes specifications
Order number

See Table 2.7
5009276

Table 2.6: Sensor Characteristics
(1) See section 2-3: Sensor functionalities. With CHRocodile C, the transmitted data are limited to up to 4 Altitudes, up to
4 Intensities and up to 3 Thicknesses.
(2) See Fig A2-2 Sensor unit mechanical plan in Appendix 2 CHRocodile C unit mechanical plan.

(3) See section 2.9: CHRocodile C performance Specifications.
(4) Resolution / Repeatability is given for optimal conditions (with a high intensity signal).

2.8.2 Optical probes characteristics
Optical probe
Probe 200µm

Probe 1mm

Probe 4mm

Probe 10mm

200µm

1mm

4mm

10mm

8nm

30nm

120nm

300nm

Accuracy (4) (5)

50nm

200nm

0.8µm

2µm

Min. measurable
thickness (4) (7)

8µm

40µm

160µm

400µm

Max. measurable
thickness (4) (7)

300µm

1.5mm

6mm

15mm

20nm

75nm

300nm

750nm

Specifications

THICKNESS
MODE

DISTANCE
MODE

Measuring range (1)
Axial resolution /
Repeatability (Rmin)(4)(5)(6)

Axial resolution /

MECHANICAL
DIMENSIONS

GLOBAL
SPECIFICATIONS

Repeatability (4)
Working distance (1) (2)

4.7mm +/- 0.3mm

15.7mm +/- 0.5mm 36.7mm +/- 0.7mm

68.7mm +/- 1mm

Spot diameter (1)

3.4µm

5µm

8µm

16µm

Lateral resolution

1.7µm

2.5µm

4µm

8µm

Max object slope (1) (3)

+/- 45deg

+/- 28deg

+/- 20deg

+/- 14deg

Length

17mm (8)

23.7mm (8)

26.6mm (8)

35.3mm (8)

Diameter

28mm (8)

33.8mm (8)

40mm (8)

33g

30g

44g

50g

Weight

Table 2.7: Optical Head Specifications
(1) See section 2.9: Optical probe specifications definitions
(2) Bottom of the optical probe to middle of the measuring range
(3) Decreasing accuracy on the limits
(4) See section 2.10: CHRocodile C performance Specifications
(5) Measurement on perpendicular mirror at 20°C with optimal Signal to Noise ratio.
(6) Axial Resolution varies with intensity signal in %. Axial Resolution = 10 x Rmin x I-0.5
(7) Refractive index n=1.5
(8) See Fig A2-1: Optical probes mechanical plan
(9) See Fig A2-2: CHRocodile C unit mechanical plan

Optical probes are interchangeable: the same CHRocodile C unit can store up to 8 different
calibration tables corresponding to different optical probes. The optical probe is totally passive,
only the CHRocodile C unit has an internal light source and electronic board which can be
considered as heat and electrical sources. However the optical probe is highly isolated from these
heat and electrical sources in order to avoid any thermal expansion which could affect the
accuracy of the sensor measuring process. Considering this opto-mechanical architecture the
CHRocodile C unit has no visible optical cable and the user don’t need to take care with this
particularly sensitive component.

2.9 Optical Head Specifications definitions

Acceptance Angle:
related to M.S

W.D

M.R

S.D

M.S

W.D : Working Distance

S.D: Spot Diameter (Size)

M.R : Measuring Range

M.S: Max Object Slope (specified for specular
object. On diffuse object, it is possible to
measure on slope up to 85°)
Fig 2-8: Optical probes specification definition

2.10 CHRocodile C performance specifications:
Axial Resolution / Repeatability:
Axial resolution / Repeatability corresponds to the static noise (standard deviation 1) on altitude or
thickness measurements. Axial resolution is measured on 1000 continuous points at different target
positions inside the measuring range. By default axial resolution specification corresponds to the
minimum value (Rmin) along the measuring range (See Fig. 2-9). The minimum value (Rmin)
corresponds to the target position where the signal to noise ratio is maximum. Resolution is inversely
proportional to the signal intensity.
Channel p
Axial Resolution (nm)

Rmin
0

Position in the
Measuring Range

Fig 2-9: Axial Resolution as a function of target position in measuring range.

Accuracy:
Accuracy corresponds to the altitude deviation between the CHRocodile C and a calibrated
interferometric reference sensor as a function of target position in the measuring range. Consequently,
accuracy is an experimental specification. By default accuracy specification corresponds to the
maximum of absolute value (Amax) (See Fig. 2-10).

Channel p
Accuracy (nm)
Amax

Position in the
Measuring Range

Fig 2-10: Accuracy as a function of target position in Measuring Range.
26

Minimum and Maximum Measurable Thicknesses:
The minimum and maximum measurable thickness specification is given for n=1.5 refractive index. It
is measured on a standard sample in the center of measuring range. T=n x (D1-D2)

D1
D2

Tmin

D1
Tmax
D2

Fig 2-11: Minimum and maximum measurable thicknesses

Operational Start up
3.1 Connections and Interfaces
All of the connection ports are located at the rear of the CHRocodile C (Cf. section 2.6 Connections
and Interfaces):
 The power supply jack,
 The RJ45 standard connector for Ethernet communication,
 The multipoint connector interface (9 pins) for trigger input / output and RS422/RS232 serial
communication,

3.1.1 CHRocodile C Stand Alone device:
The device can be used as a stand-alone device in order to perform selective distance or thickness
measurements. In this condition, only the power supply and Ethernet connector or multipoint
connector are useful.
Power supply
The CHRocodile C has two pluggable screw terminal for power supply with 24VDC +/-10%.
Connect the set of power cable supply associated to the Power Supply Adapter (100-240VAC to
24VDC +/-10%) delivered with the CHRocodile C unit.
Ethernet connector
Connect the isolated RJ45 standard connector from the CHRocodile C unit to an Ethernet network
(PC). Use shielded cable for the data port connection (minimum category 5 cable).
The default CHRocodile C IP address is: 192.168.170.4
Configure the PC Ethernet port to the following address: 192.168.170.X (X≠4)
The CHRocodile C can also be configured to use auto-configuration of the IP-Address through
a DHCP server.
To configure the Ethernet port of your PC, you must open the ‘Network connection properties’ menu.
After selecting the right Ethernet card (connected to the sensor), click on ‘network protocol (TCP/IPv4)’
and click ‘Properties’. Set the IP address of the PC and the mask. For a standard use the mask should
be set to 255.255.255.0.
If you need to configure the sensor to another IP address (different than 192.168.170.4), you need to
use the $IPCN command (Cf. Appendix 1). This could be useful in case of multiple CHRocodile C
connection on a single computer.

Multipoint connector interface
Data transmission can be done through RS422/RS232 serial communication, using the so called $protocol. Two formats are available (ASCII/BIN) for sending the data from the optical sensor via the
RS422.
The data can thus be transferred to a computer as ASCII-symbols (telegram
format) and e.g. viewed with a terminal program (e.g. Tera Term, Freeware).
Output in BIN format, command: $BIN
Output in ASCII format, command: $ASC
The transfer rate for the serial interface port is selected under serial port baud rate.
The standard Baud rates available for selection are 9600, 19200, 38400, 57600, 230400, 460800 ,
921600 Baud and 1843200 Baud. Arbitrary nonstandard Baud rates can also be configured.

3.1.2 CHRocodile C integrated on measurement system:
In addition to the Power supply and Ethernet connector or multipoint connector interface used for
stand-alone device, the CHRocodile C needs to be connected to other interfaces to be integrated into
complex measurement configuration systems. The other possible interfaces are described hereafter:
-

The multipoint connector interface for Trigger Input/Output and Serial interface RS422,

The 8 pins mini-DIN connector for external analogue converter box to add 2 encoder inputs.

Encoder-input
The incremental encoder-input makes it possible to precisely assign the measurement point and axis
positions without additional hardware. The CHRocodile C can manage with 2-axis Encoders if the
optional analogue converter box is connected to the CHRocodile C 8-pins mini-DIN connector.
For an exact distance or thickness measurement it is necessary for every measurement value to be
assigned to the exactly correct spatial coordinates. This data must be recorded in the system and
transferred to the evaluation processing unit over the internal interface. To accomplish this, the sensor
must be equipped with the analogue box accessory.
Default are the encoder inputs not terminated.
Tye Sw0t02 to GND to terminate with 120 Ohm channel 0 to 2
Tye Sw3t04 to GND to terminate with 120 Ohm channel 3 to 4

If the encoder-signals are fed through the sensor and additional other devices are connected (e.g. for
axis control), the 120 Ohm termination can also be deactivated. Since the device has to be opened to
do this, you should contact Precitec Optronik before beginning any work of this kind.

Trigger Input/Output
The trigger options make the lighting cycle externally controllable and the synchronization between
e.g. a scanning system and the CHRocodile C measurement rate. This means that external triggering
is possible for every measurement up to the full measurement rate of 4000Hz.
The interface contains the connection points for the synchronization and RS422 serial communication.
Data transmission / sensor configuration
Data transmission and sensor configuration can be done through RS422 serial communication through
the multipoint connector interface or through Ethernet port.

3.2 CHRocodile Explorer and Drivers installations
3.2.1 CHRocodile Explorer installation:
CHRocodile Explorer is a Man-Machine interface which allows to configure, to visualize measurement,
to save data etc… CHRocodile Explorer can manage with all PRECITEC CHRocodile point sensors.
Refer to CHRocodile Explorer Manual to obtain more specifics information.

3.3 Communication with CHRocodile C
There are three possible ways to communicate with the CHRocodile C: via Precitec CHRocodile
Explorer software, via the CHRocodile C DLL and using the ASCII commands sent to the CHRocodile
C through serial interface (RS 422) or Ethernet communication. Up to 10 CHRocodile C can be
connected and controlled by a single computer (Windows XP, Windows 7 or Windows 8 OS, 32 and
64bits). CHRocodile C is automatically detected through Ethernet network (broadcast mode).

3.3.1 Via CHRocodile Explorer:
CHRocodile Explorer software is delivered with the sensor and is useful to configure sensor, to
visualize continuous measurements and to save data.
In order to obtain further detailed on CHRocodile Explorer functionalities, please refer to
CHREplorerManual.
30

3.3.2 Via CHRocodile C DLL:
DLL is used to interface the sensor with a general-purpose user program. This CHRocodile C DLL is
written in C, C++ language and is intended for .NET compatible language. This DLL allows to use
whole CHRocodile C functionalities. In order to obtain further detailed refer to CHRocodile C DLL
documentation.
A CD containing the DLL, some code examples and the operating Manual is delivered with the
CHRocodile C.

3.3.3 ASCII command communication
The ASCII commands can be sent to the controller via the RS422 interface using a specific command
structure described on Appendix 1.
Serial interface communication can be used to configure the sensor and receive measurement data.
As an example, the Windows™ « Hyper Terminal »™ utility can be used to send the commands and
configure the sensor via the RS232 or RS422 communication port.

Measurements Start Up

4.1 Calibration Table
The CHRocodile C unit can store up to 8 different calibration tables corresponding to different optical
probes. In order to start measurement you need to download or select the calibration which
corresponds to the used optical probe (Cf. command $SEN in Appendix 1). Calibration table consists
in a look up table which gives the correspondence between the peak position (Barycenter data) and
the Altitude data.
The CHRocodile C is calibrated at factory with a certified calibration bench.
The calibration table depends on both spectrometer and optical probe. Consequently a calibration
table is specific to one set of CHRocodile C sensor (CHRocodile C unit + optical probe), it can’t be
used on another set even if you are using the same optical probe type (i.e same measuring range).

Fig 4-1: Example of calibration table for a single channel

4.2 Dark Acquisition
Even when there is no surface in the probe’s measurement range, the signal on the detector is not
zero. These non-zero values for each pixel on the detector is due to electronic dark and mostly to flare
corresponding to unwanted back-reflected light on optical lenses surfaces. This Dark signal which
limits the measurement dynamics of the sensor can be remove from the useful signal.
In order to eliminate the influence of this undesirable light, a dark reference is performed on the sensor
(Cf command DRK in Appendix 1). The Dark reference acquisition must be done when no object is in
the measurement range.
32

4.3 Mechanical interfacing
After completing the operational startup, i.e. connecting with the power supply, proceed with
initializing, then communication is ready and mechanical interfacing should be done.
Mechanical interfacing consists in:
-

Connecting the optical probe, which suits to your application, to the CHRocodile C unit. The
optical probe is simply screwed on the CHRocodile C unit (Cf. Figure 4.2).

Screw optical head
on sensor unit

Fig 4-2: Interchangeable optical heads

And, fixing the CHRocodile C on your system using the interface threaded M3 holes located
on the soleplates and on the lateral surfaces of the CHRocodile C unit or using the ring
surrounding the optical probe (Cf. Fig 4-3).

Possible fixture on
the surrounding ring.
a-

Fig 4-3: CHRocodile C unit mechanical interface: fixture holes on:
a- lateral surface 1
b- soleplate,
c- lateral surface 2.

4.4 Basic Settings Configuration
In order the CHRocodile C to be operational for startup some basic parameters should be set up. You
can also refer to the CHRocodile C quick start guide documentation.
Basic setting configuration consists in selection of:
•

Measuring Range: The CHRocodile C could accept up to 8 calibration tables. Each calibration
table corresponds to a unique optical probe. Consequently, depending on the optical probe
which is mounted on the CHRocodile C unit, the operator must select the right measuring
range or calibration table. (Cf. command $SEN in Appendix 1)

•

Data transmission: The CHRocodile C can transmit different data: up to 4 Altitudes, up to 4
Intensities and up to 3 Thicknesses. Depending on the application, operator must select the
right data. (Cf. command $SODX in Appendix 1)

•

LED intensity level: The LED intensity Level can be adjusted from 0 to 100%. As for
measuring rate, this adjustment essentially depends on object reflectivity. Adjust LED intensity
in order to obtain a high signal intensity, but avoid saturating the detector (intensity LED blinks
orange). In order to adjust LED intensity, use the LAI command (Cf. Appendix 1).
34

•

Measuring Rate: Instead of adjusting intensity or in addition to LED intensity adjustment, it is
also possible to adjust the measuring rate. The measuring rate is related to data transmission
frequency. The CHRocodile C maximum measuring rate is 4KHz. The higher the measuring
rate is the lower the signal intensity is. Consequently, depending on the object reflectivity
under measurement, the measuring rate (measuring frequency) must be adjusted in order to
remove saturation or too low intensity signal. In order to adjust measuring frequency, use the
SHZ command (Cf. Appendix 1).

4.5 Data measurement Training
When mechanical interfacing is done, the object to be measured must be positioned inside the
measuring range of the CHRocodile C optical probe.
This procedure is valid for altitude and thickness measurement, i.e. to perform topographic
measurement on reflecting object or to perform thickness measurement on transparent object.
Measuring altitude procedure consists in:
-

Adjusting the axial position of the target in order the target is centered inside the optical
sensor measuring range. To do this, one can move the optical probe or the target along the
optical axis. Thus, it is recommended to fix the optical probe or the target on a translation
plate.

Adjusting the spot on the area to be measured.

Target

Translation plate

Target

Translation plate
Fig 4-5: Axial position adjustment
When the target is correctly positioned in front of the optical head and basic configuration is
correctly set, it is possible to collect the needed data using the SODX command (Cf. Appendix 1).
35

In order to record the data corresponding to the CHRocodile C unit, the Ethernet port or the
RS422/RS232 communication port must be connected to the computer.
It is now possible to perform an area scan:
-

In order to scan the target, one can move the optical probe or the target inside optical axis
perpendicular plan. Thus, a 2 axis translation system is required. The altitude or thickness
data is recorded during the scan. In order to synchronized the data acquisition with the moving
session, one need to connect the trigger in/out to the translation system. The command TRG,
enables an exact alignment of the sensors sampling intervals with the movement of a
scanning axis.

However, if scan velocity is not constant, the pitch between each recorded point is not
constant and the global topography will be distorted. To overcome this image deformation it is
important to assign precisely each measured points and axis positions. To do so, one need to
connect the incremental encoder-input. The CHRocodile C can manage with 2-axis Encoders
using the analogue converter box accessory.

Appendix 1: Advanced Configuration
1. Commands List
command

arguments

answer on query

<0,1>/<0..100>
or

<0,1>

<0 .. 500, ?>

comments
Auto Adapt Light source:
First parameter: auto adapt on(1) or off(0, default)
Second parameter, only needed in case first param is 1:
desired detector level in % of saturation level (0-100), 33 is
default.

AAL

The autoadapt mode is also disabled by the LAI command!

Abbé number:
Dispersion, only active, if SRT 0 selected (no preloaded
Index table)
0 (default): no dispersion
You should give as many Abbé numbers as there are
layers to be measured, that is (number of Peaks - 1).

ABE

The first parameter describes the nearest Layer.
AVD
AVS

<1 . . . 999, ?>

Average Data

<1 . . . 999, ?>

Average Spectrum

Baud rate>
<0,1>
<0,1>
BDR

CTN

Continue (Measuring)
<0 . . . 65535, ?>

BauD Rate for serial port
Command: “Baud rate” If 1st arg <= 8, then baudrate
index is selected, otherwise free custom baudrate is given
index of baud rate in [bit/s]
0: 9600; 1: 19200;
2: 38400; 3: 57600;
4: 115200; 5: 230400;
6: 460800; 7: 921600;
8: 1843200
2nd arg: HW Handshake on/off
Response: 2nd arg: effective baudrate (may deviate)
free running mode
See also: TRE, TRG, TRW
Continuously Refresh DarK
0 (default, no refresh)-65535 (full replacement with every
spectrum)

CRDK

See also: TRG, TRE, CTN
VER

VERsion
Responds with a string containing several lines with
Key-Value pairs
See also: IDE

Table A1.1: Commands list

2. Detailed Commands Description
2.1 CTN Command
This command lets the sensor exit any of the above trigger modes and returns to freerun.
No parameters are needed, so the syntax is just $CTN.

2.2 DRK Command
This command lets the sensor acquire a background spectrum that the incoming spectra will
be corrected for during normal operation. The acquisition of this background will take about
one second. The resulting background spectrum will be saved in the internal non-volatile
memory.
This command does not take any parameters, so the syntax is just $DRK.

It is important to remove any object within the measuring range before applying
the command.

The command response contains a number which is a measure of the background intensity. A
high background intensity can be related to e. g. stray light.
Command syntax:
$DRK
Command

Description

$DRK

Execute a Dark reference

Response: $DRK127 (63.2Hz)ready[CR/LF].

2.3 ENC Command

The encoder inputs and related commands ETR or ENC are available only with
the analogue converter box accessory.
This is an encoder control command. It has the following format:
ENC where arg1 denotes a certain function and arg2 some
parameter related to it.
42

The following functions are defined:
Arg1
0

Function
Arg2
Set / Read current encoder
counter value
Encoder counter value to set

Set count source

0: Pulse on A0, 1: Pulse on B0, 2: Pulse on A1 . . . 9: Pulse on B4
10: Pulse on SyncIn
11..14: not used
15: Quadrature A/B on encoder input

Set preload value

Value to load into encoder counter on preload event

Set preload function

See table below

The preload function defines under which condition the value set with function 2 will be loaded
into the encoder counter. The respective argument 2 is a bit field as defined below:

Bit(s)
0
1
2

Preload function value calculation
Function
0: Preload once, 1: Preload each time
0: preload event on raising edge or high level, 1: falling edge or low level
0: the preload event is triggered by an edge 1: it is triggered by the level

3
0: Preload function inactive, 1: active (in case of “preload once”, this bit will be automatically reset)
7 .. 4 0: Pulse on A0
1: Pulse on B0
2: Pulse on A1
…
9: Pulse on B4
10: Pulse on SyncIn
11..14: not used
15: Immediate preload

2.4 ETR Command

The encoder inputs and related commands ETR or ENC are available only with
the analogue converter box accessory.

The settings will not be saved in the nonvolatile memory by the $SSU
command.
43

This command groups several functions related to encoder triggering. The encoder trigger can
work in two ways:
1. Roundtrip trigger (scanning application)
2. Endless trigger
Roundtrip trigger (scanning application)
The encoder trigger is implemented as a state machine (see figure below). In the idle state, it
waits for the encoder counter of the selected axis to pass the start position (in either direction)
where it generates the first trigger event. Then the trigger interval value is added to the current
position and when this position is reached, the next trigger event is generated. This step is
repeated until the stop position is encountered.
The generation of trigger events is now stopped. If triggering during return movement is
selected, the state machine waits for the stop position to be passed once again and generates
trigger events similarly to the forward movement (the trigger interval is now subtracted instead
of added) until the start position is reached. The state machine then goes back to the idle
state. If no Trigger during return movement is selected, the state machine waits for the start
position to be passed over (during return movement) and then passes to the idle state.

Fig A1-1: Roundtrip Trigger

Endless trigger
This mode is destined for applications where the encoder primarily moves in one direction as
in production lines and where equidistant sampling is needed. In order to use this mode, only
a trigger interval has to be parametrized.

Fig A1-2: Endless Trigger
Format
The command has the following format: ETR where function is:
0: Set start position ((int) arg = start position to set, see figure)
1: Set stop position ((int) arg = stop position to set, see figure)
2: Set trigger interval ((float) arg = trigger interval, see figure) Note that the interval can be
given in fractions of encoder counts.
3: Enable encoder (0: disabled, 1: enabled)
4: Enable triggering during return move, see figure. 0: disabled, 1: enabled.
5: Select encoder counter
6: reserved
7: Enable endless triggering (in this mode, start and stop positions are ignored, trigger events
will be generated on the current position and the trigger interval) 0: disabled, 1: enabled.

2.5 IPCN Command
Short description:
This command allows to configure TCP/IP address and subnet mask.
Command syntax:
$IPCN
Command

Description

$IPCN 1

Configured as DHCP client

$IPCN

$IPCN 0 192 168 170 4 255 255 255 0 0

Configured as static IP address

$IPCN

IP Address = 192.168.170.4
Subnet Mask = 255.255.255.0
MTU = 0 (no jumbo packets)
MTU argument gives the maximum
transferable unit which can be anything
between 1500 and 9000 bytes per TCP
packet (jumbo packets).

2.6 LAI Command
Short description:
This command allows to adjust LED intensity in order i.e. to remove saturation.
Command syntax:
$LAI
Param: is Led intensity (0...100%)
Command

Description

$LAI 95

Write Led intensity 95%

Response: $LAI 95[CR]ready[CR/LF].

$LAI ?
Response: $LAI ?

Read Led Intensity
95ready[CR/LF].

2.7 NOP Command
Short description:
This command allows to set the number of peak to evaluate.
WARNING: In confocal mode, if less than NOP peaks are detected, all thicknesses signals will
be invalidated because peak identification is not possible.
Command syntax:
$NOP
Param: is Number of Peak from 1 to 4
Command

Description

$NOP 3

Write Number of Peak (3)

Response: $NOP 3[CR]ready[CR/LF].

$NOP ?
Response: $NOP ?

Read Number of Peak
3ready[CR/LF].

2.8 SCA Command
Short description:
The command Scale allows to query of Full Scale in micrometers.
A distance value of 32768 on the serial interface would mean a distance in (Full Scale)
micrometers. To convert the integer distance value (d) received from the serial interface to a
value in micrometers (D), use the formula:
D[µm] = d[integer] / 32768 * Full Scale.
Command syntax:
$SCA
Command

Description

$SCA ?

Read Full Scale

Response: $SCA ?

3320ready[CR/LF].

2.9 SEN / SENX Command
Short description:
The $SEN command is used to activate the chromatic—confocal calibration related to a specific
sensor head. With the single channel device, up to sixteen calibrations can be uploaded and
stored in the device. With the Chrocodile C device, up to eight calibrations are supported.
53

The format of the command is as follows:
$SEN n where n is the calibration table index. As the possible measuring range of each probe is
much higher than the range for which it is specified and guarateed to adhere to the
specifications, there is a way to use the full range with degraded precision. This might be useful
in applications where not the full precision is required. In order to enable the full range, send
$SEN n 1.
The currently active calibration table can also be queried:
$SEN? (or query flag in case of packet protocol) – returns active calibration index and if the
extended range is enabled (1) or not (0)
$SENX? - returns more details of the active calibration, I. e. index, serial number of the related
probe and the current range in micrometers:
$SENX?0, SNr: 0, Range: 7999umready
$SENX enum? - (“enum” as a string argument in case of packet protocol) returns complete list of
calibrations.
Command syntax:
$SEN
Command

Description

$SEN?

Returns active calibration index and if
extended range is selected

Response: $SEN?

0 0ready[CR/LF].

$SEN1 1
Response: $SEN1

1ready[CR/LF].

Set calibration table n°1 with extended
range

2.10 SHZ Command
Short description:
The command SHZ set sample rate in Hz
It is possible with this command to realize any sample rates between 100Hz and 2000Hz.
If the value is not accepted, the sensor responds with the string "not valid".
Due to the nature of the internal time base, not every sample rate can be realized exactly. In
order to give the user the possibility to know the exact frequency, to which the sample rate has
been "rounded", the frequency can be queried with "?" and will be returned as ASCII floating
point number with 6 decimals.
Command syntax:
$SHZ
Param: is sample rate (32Hz…4000Hz)
Command

Description
54

$SHZ 1000

Write Sample Rate (1000 Hz)

Response: $SHZ 1000[CR]ready[CR/LF].

$SHZ ?

Read Sample Rate

Response: $SHZ ?

1000ready[CR/LF].

2.11 SODX Command
Short description:
Select Output Data (extended)
SODX directly selects the data words that will be included in the output telegram by specifying
their
indices.
For example SODX 83, 16640, 16641 will output the sample counter, the distance and the
intensity.
Command syntax:
$SODX [A0] [A1]…[AN]
[Ax] is optional parameters
Signal ID's scheme

CLS02 CLS1 CLS2,3 CLS0,5 CLS4

Grandissement 25,4 12,7
MR

15,9

0,2

15,9

5,1

2,3

0,5

Table A1.2: SODX command: Signal Identity’s scheme.

Global Exposure Information:
Definition: Bit 8 = 0 (Bit 8 to 15 = 0)
Type:
Float
Command

Description

$SODX 64

Start of exposure Time (in
nanoseconds)

Response: $SODX 64[CR]ready[CR/LF].

$SODX 65
Response: $SODX 65[CR]ready[CR/LF].

$SODX 66

Start of exposure PositionX(X
encoder position on beginning of
exposure)
Start of exposure PositionY(Y
55

Response: $SODX 66[CR]ready[CR/LF].

$SODX 67
Response: $SODX 67[CR]ready[CR/LF].

$SODX 68
Response: $SODX 68[CR]ready[CR/LF].

$SODX 69
Response: $SODX 69[CR]ready[CR/LF].

$SODX 70
Response: $SODX 70[CR]ready[CR/LF].

$SODX 71
Response: $SODX 71[CR]ready[CR/LF].

$SODX 72
Response: $SODX 72[CR]ready[CR/LF].

$SODX 73
Response: $SODX 73[CR]ready[CR/LF].

$SODX 74

encoder position on beginning of
exposure)
Start of exposure PositionZ(Z
encoder position on beginning of
exposure)
Start of exposure PositionU(U
encoder position on beginning of
exposure)
Start of exposure PositionV(V
encoder position on beginning of
exposure)
End of exposure PositionX(X
encoder position on end of exposure)
End of exposure PositionY(Y
encoder position on end of exposure)
End of exposure PositionZ(Z encoder
position on end of exposure)
End of exposure PositionU(U
encoder position on end of exposure)

Response: $SODX 74[CR]ready[CR/LF].

End of exposure PositionV(V
encoder position on end of exposure)

$SODX 75

FirstExposureCount

Response: $SODX 75[CR]ready[CR/LF].

$SODX 76

ExposureFlags

Response: $SODX 76[CR]ready[CR/LF].

$SODX 77
Response: $SODX 77[CR]ready[CR/LF].

$SODX 78
Response: $SODX 78[CR]ready[CR/LF].

$SODX 79
Response: $SODX 79[CR]ready[CR/LF].

$SODX 80
Response: $SODX 80[CR]ready[CR/LF].

$SODX 83

RealExpTimeNs(Effective exposure
period in nanoseconds)
RealLightingTimeNs(Effective lighting
period in nanoseconds)
TriggerLostCounter (Accumulates
trigger events that have occurred
during exposure and therefore have
been ignored.
NumberOfValidPeaks (Number of
peaks that have been found in the
spectrum)
SampleCounter

Response: $SODX 83[CR]ready[CR/LF].

Peak Signal:
Definition: Bit 8 = 1
Type:
• Value encoding (Bits 15, 14):
For geometrical quantities like thickness or distance
• 00: float in micrometers, including refractive index (geometrical thickness)
• 01: integer 16bit, scaled as fraction of measurement range, without refractive
index (optical thickness).
Distance and thickness values are given as: d[µm] = value * $SCA[µm] /
32768.
In order to get the geometrical thickness, the value has to be multiplied by the
index of refraction of the material.
• 10: 32bit integer value in nanometers, including refractive index (geometrical
thickness)
• 11: integer 32bit, scaled as fraction of measurement range, without refractive
index (optical thickness)
Distance and thickness values are given as: d[µm] = value * $SCA[µm] / (1 <<
31).
In order to get the geometrical thickness, the value has to be multiplied by the
index of refraction of the material. This format yields the highest theoretical
resolution.
For non-geometrical quantities (like intensity)
• Floating point values:
• 00: float
• 01: truncated 16bit integer value
• 10: 32bit integer value in 16.16 format
• 11: undefined
• Integer Values:
• 00: 32bit integer
• 01: least significant 16 bit
• 10: most significant 16 bit
• 11: undefined

BIT
Peak Signal

13
0

12
0

0
0
0
1
1

0
1
1
0
0

11
Statistics
0 Average
1 Std . Deviation
0 Number of valid values
1 Minimum
0 Maximum
1 Peak - to -peak difference

15 14 13 12 11
Value
Statistics
encoding

( max -min )

Statistics are not supported by CHRocodile C. Consequently the
respective bit 11 to 13 are set to 0.

9
1
0
0
0
0
0
0

10
0

2
X
0
0
0
0
1
1

9
Measuring
Mode

1
X
0
0
1
1
0
0

0
X
0
1
0
1
0
1

Measuring Mode

4
3
Peak
Number

4
0

3
0

0
1
1

1
0
1

Peak Number

1st peak
2nd peak
3rd peak
4th peak

Peak Signal Offset

Thickness
Altitude
I ntensity (%)
Intensity Level
Barycenter
Peak Value Median
Peak Width

Example:

Value encoded
in integer 16 bits

Command

Description

$SODX 28840

Altitude, 2nd peak

2
1
0
Peak Signal
Offset

Response: $SODX 16648[CR]ready[CR/LF].

Additional information:
Peak Signal Offset (Bits 0 to 2)
Signal ID Offset

Signal Name

Remarks

Peak Value

Scaled peak distance

PeakIntensity

Intensity of peak

CCDSaturation

max. CCD illumination of related spectrum

PeakPos

CCD pixel pos

reserved

PeakWidth

reserved

confocal mode only: given in CCD pixels

Peak Number (Bits 3 and 4)
Bits 3 and 4 are used to define the Peak Number which will be
processed to calculate the demanded data. The following quantities
are available:
Measuring Mode (Bit 9)
Thickness: If bit 9 is set to 1, then the resulting value is thickness
corresponding to the difference of the peak as defined in bits 3 and 4
and the next peak. This facility is used to request thicknesses directly.
NOTE
This difference value is not corrected for the index of refraction.
Consequently, in order to obtain the real thickness data, one must
divide the result by the refractive index.
Altitude: If bit 9 is set to 0, then the resulting value is the Altitude
corresponding to the peak number defined in bits 3 and 4.

Statistics (Bit 11 to 13)

Statistics are not supported by CHRocodile C.
Consequently the respective bit 11 to 13 are set to 0.
59

2.12 SSU Command
Short description:
The command SSU saves Setup
Saves current setup to non-volatile memory. The Setup will be restored upon next power up.
Command syntax:
$SSU
Command

Description

$SSU

Saves current setup

Response: $SSU [CR]ready[CR/LF].

2.13 STA Command
Short description:
The command STA starts serial data output
This mode can be stored in the nonvolatile memory. If stored, the CHRocodile C will begin
immediately to output data telegrams on the next power-up.
Command syntax:
$STA
Command

Description

$STA

Starts serial data output

Response: $STA [CR]ready[CR/LF].

2.14 STO Command
Short description:
The command STO stops serial data output
This mode can be stored in the nonvolatile memory, so on the next power up the CHRocodile C
will not begin to send measurement data until the output is restarted by the "STA" command.
Command syntax:
$STO
Command

Description

$STO

Stops serial data output

Response: $STO [CR]ready[CR/LF].

2.15 THR Command
Short description:
The command THR lets you specify an intensity threshold for the distance detection.
It may be useful to specify a high threshold to reject all noise spikes during a measurement or to
specify a low threshold to get a (noisy) result from very black surfaces. When the signal is below
the threshold, 0 is output for distance and intensity. The threshold is in arbitrary units which may
be subject to change in future software versions.
At faster sample rates, lower settings for threshold can be used than at slower sampling rates.
The reason is, that at slower sampling rates, the stray light of fiber and coupler is integrated
longer on the detector. Even though this signal is automatically subtracted as "dark reference",
the statistical variations of this signal are stronger, the higher the dark signal becomes. If a
typical value for good noise suppression and maximum sensitivity at 2kHz sampling rate could
be 20, at 100Hz 50 would be needed.
If the sensor doesn’t detect a signal which passes the threshold, 0 is output for distance and
intensity.
Command syntax:
$THR
Param: is intensity threshold
Command

Description

$THR 35

Write Intensity Threshold

Response: $THR 35[CR]ready[CR/LF].

$THR ?
Response: $THR ?

Read Intensity Threshold
35ready[CR/LF].

2.16 TRE Command
Short description:
This command lets the sensor enter a trigger mode where one trigger event will produce one
sample. Trigger signals can be SyncIn or Encoder inputs, depending on $ETR settings, see
$ETR description below. $TRE is particularly useful in conjunction with encoder based trigger
generation as described in the $ETR section below.

The encoder inputs and related commands ETR or ENC are available only with
the analogue converter box accessory.
The maximum frequency (or the shortest interval of two consecutive trigger events) is defined by
the cycle frequency ($SHZ). Trigger events that occur while the sensor is idle will cause an
immediate exposure. If a trigger event occurs during an ongoing acquisition cycle, then the
respective exposure will be delayed until the current cycle is completed. In this case, the
TriggerDelayed – Flag (Bit 2) is set in the flags signal of the delayed exposure. This flags signal
is a global signal (ID = 76) that can be requested just like any other signal using $SODX. If more
than one trigger event occurs during an ongoing exposure cycle, then only the first event will
result in a delayed exposure cycle as described above, all consecutive trigger events will be
ignored. In this case, the TriggerIgnored – Flag (Bit 1) will be set in the flags signal of the
delayed exposure.
Command syntax:
$TRE
Command

Description

$TRE

Trigger each

Response: $TRE[CR]ready[CR/LF].

2.17 TRG Command
Short description:
The command TRG is a Wait For Trigger. The command enables an exact alignment of the
sensors sampling intervals with the movement of a scanning axis.
It stops the sensor after completion of the current data telegram and puts it in a waiting state.
This state is left by a trigger event (rising edge on the Sync in, Encoder Trigger).
Command syntax:
$TRG
Command

Description

$TRG

Wait For Trigger

Response: $TRG[CR]ready[CR/LF].

2.18 VER Command
Short description:
The command VER give the Version of CHRocodile C.
The command sends back an ASCII string which gives information on the serial number of the
CHRocodile C (SN: ...), the DSP software (DSPsoft: ...) and the microcontroller software (C: ...).
Command syntax:
$VER
Command

Description

$VER

Read Versions

Response:
ChrocodileCompact[CR]
device_serial_number = 201223[CR]
firmware-version = 1.2.3[CR]
build = 2016-09-29 427f188cbd[CR]
ready[CR/LF].
>>

Appendix 2: Mechanical Plans
1. Optical probe mechanical plans

a- Probe 0.2mm

b- Probe 1mm

c- Probe 4mm

d- Probe 10mm
Fig A2-1: Optical Head Mechanical plans: a- 0.2mm b- 1mm c- 4mm d- 10mm

2. CHRocodile C unit mechanical plans

Fig A2-2: CHRocodile C sensor unit mechanical plans:

3. CHRocodile C unit mechanical interface plans

Fig A2-3: CHRocodile C unit mechanical interfaces
Three surfaces are designed to fix the CHRocodile C unit on customer system. On these 3 surfaces, 4
M3x4.5 threaded holes are available. Positions of threaded holes are specified on the Figure A2-3.
It is also possible to fix the CHRocodile C unit on the front ring of 34mm diameter.
Consequently several mechanical interfaces are available on this sensor in order to ease the
integration on customers / integrators systems.

Appendix 3: Trouble Shooting
1.1 Power off
The Status LEDs are off when the power supply cable is not connected:
-

Check the power cable.

1.2 Communication error:
No possible Ethernet communication between CHRocodile C and your computer:
-

Check the Ethernet cable is plugged correctly in RJ45 sensor unit connector.

Check the IP configuration for your PC and the CHRocodile C unit (Cf. $IPCN command in
Appendix 1).

If you are using a switch, then try to connect directly from your LAN network to the sensor unit.

If possible, a Peer-to-Peer connection is recommended.

No possible serial communication between CHRocodile C and your computer:
-

Check the multipoint cable is plugged correctly in multipoint connector (9 pins),

Check the baud rate is correct.

1.3 Distance Measurement:
The target is positioned in front of the sensor, and no distance measurement is collected for all
channels.
-

Set the measuring frequency to minimum ($SHZ100).

Set the LED intensity to maximum ($LAI100).

Check if a white light spot is emitted from the optical probe and if it is focused on the target.

Check if the target is inside the measuring range of optical probe (Cf. section 2.8).

Check if the target surface is normal to the optical probe axis. The maximum angle between
target surface and optical axis is given by the maximum measurable slope (Cf. section 2.8).

Check if the distance is transmitted ($SODX 16640 or SODX 256),

Check that a calibration table is uploaded ($SCA?)

Then, check and store the raw signal (this file could be demanded by PRECITEC technical
support team). The raw signal should show one peak.

1.4 Thickness measurement:
The target is positioned in front of the sensor, and no thickness measurement is collected for all
channels.
-

Check that the target thickness is inside minimal and maximal measuring thickness range,

Check the target transparency,

Set the measuring frequency to minimum ($SHZ100).

Set the LED intensity to maximum ($LAI100).

Check if a white light spot is emitted from the optical probe and if it is focused on the target.

Check if the two surfaces of the target are inside the measuring range of the optical probe (Cf.
section 2.8).

Check if the target surface is normal to the optical probe axis. The maximum angle between
target surface and optical axis is given by the maximum measurable slope (Cf. section 2.8).

Check if the two distance peaks are transmitted ($SODX 16640 16648),

Then, check and store the raw signal (this file could be demanded by PRECITEC technical
support team). The raw signal should show two peaks.

If after reading the previous section you didn’t succeed in resolving your problem, please contact your
vendor for technical support. In order to be more efficient, we recommend to fill the following technical
support datasheet and if necessary prepare the files which are demanded in previous section.

Appendix 4: Technical support

Technical Support
Date :

CUSTOMER :

PRECITEC Number:

PRODUCT IDENTIFICATION
Sensor Unit Serial Number :

Optical Head Serial Number :

Firmware Serial Number :

PROBLEM IDENTIFICATION
Type :
Software
Optic
Mechanic
Electronic
Description :

Photos:

Attached files :
Photos
Raw data
Diagnostic file
70

Source Exif Data:
File Type : PDF File Type Extension : pdf MIME Type : application/pdf PDF Version : 1.4 Linearized : No Page Count : 63 Language : fr-FR Tagged PDF : Yes XMP Toolkit : 3.1-701 Producer : Microsoft® Word 2013 Title : CLS User Manual Creator : DR Creator Tool : Microsoft® Word 2013 Create Date : 2016:10:12 14:16:15+02:00 Modify Date : 2016:10:12 14:16:15+02:00 Document ID : uuid:46F59D9D-F6A8-4252-9FD2-1D55109778FF Instance ID : uuid:46F59D9D-F6A8-4252-9FD2-1D55109778FF Part : 1 Conformance : A Author : DR
EXIF Metadata provided by EXIF.tools

CLS User Manual CHRocodile Compact

CHRocodile%20Compact%20User%20Manual

CHRocodile%20Compact%20User%20Manual

Navigation menu

Versions of this User Manual:

Views

Navigation