PRIMESOperating Manual

Translation of the Original Instructions

BeamMonitor50 HQ
LaserDiagnosticsSoftware

Revision 01/2015 EN

BeamMonitor50 HQ

Table of Contents
1. Laser safety precautions4

2. Introduction
5
2.1 Laser beam measurement��������������������������������������������������������������������������������� 5
2.2 PRIMES - the Company������������������������������������������������������������������������������������� 6
2.3 BeamMonitor50 HQ�������������������������������������������������������������������������������������������� 7
2.4 What is covered by this manual�������������������������������������������������������������������������� 8
3. Setup
10
3.1 Safety Instructions and Mechanical Installation����������������������������������������������� 10
3.2 Hardware installation���������������������������������������������������������������������������������������� 11
3.3 Software installation����������������������������������������������������������������������������������������� 14
3.3.1 System demands�������������������������������������������������������������������������������� 14
3.3.2 Installing the Software������������������������������������������������������������������������� 14
3.3.3 Setting up the USB-converter software (option)��������������������������������� 14
3.3.4 Setting up an ethernet-connection������������������������������������������������������ 16
3.4 Starting the LaserDiagnosticSystem���������������������������������������������������������������� 17
3.5 Power-up and Change of Configuration����������������������������������������������������������� 17
4. Manual Operation of the BeamMonitor50 HQ
19
4.1 Measurement and Presentation - a Short Description������������������������������������� 19
4.2 Operation of the BeamMonitor50 HQ��������������������������������������������������������������� 20
4.2.1 Safety with regard to leakage radiation: Mechanical adjustment of thesensor and checking the system configuration�������������������������������������������� 20
4.2.2 Performing measurements������������������������������������������������������������������ 21
4.2.3 Presentation and documentation of the measured results������������������ 21
5. The Operation of the LaserDiagnosticSoftware
22
5.1 Logical Structure of the Graphical User Interface�������������������������������������������� 22
5.2 The Graphical User Interface��������������������������������������������������������������������������� 23
5.3 Adjustment of parameters for measurement���������������������������������������������������� 23
5.4 Measuring�������������������������������������������������������������������������������������������������������� 25
5.4.1 Single Measurement��������������������������������������������������������������������������� 25
5.4.2 Environment���������������������������������������������������������������������������������������� 27
5.4.3 BeamFind Settings������������������������������������������������������������������������������ 27
5.4.4 Protocol����������������������������������������������������������������������������������������������� 28
5.4.5 AdjustMode����������������������������������������������������������������������������������������� 28
5.5 Presentation and Documentation of Measured Results ���������������������������������� 31
5.5.1 Contour lines��������������������������������������������������������������������������������������� 32
5.5.1.1 Free variable Contour Lines������������������������������������������������������������� 32
5.5.1.2 Fixed Contour Lines������������������������������������������������������������������������� 32
5.5.2 Isometry (3-D Presentation)���������������������������������������������������������������� 33
5.5.3 Pseudo colors ������������������������������������������������������������������������������������ 33
5.5.4 Symmetry Check��������������������������������������������������������������������������������� 33
5.5.4.1 The Algorithm����������������������������������������������������������������������������������� 35
5.5.5 Color Tables���������������������������������������������������������������������������������������� 35
5.5.6 Review - 86% and 2nd Order Moments���������������������������������������������� 36
5.5.7 Graphical Review�������������������������������������������������������������������������������� 37
5.5.8 Data management������������������������������������������������������������������������������� 38
5.5.8.1 Storing and reloading of measured data ����������������������������������������� 38
5.5.8.2 Storing of Preferences to file, and opening of such files������������������ 38

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5.5.8.3 Printing��������������������������������������������������������������������������������������������� 38
5.5.8.4 Copy������������������������������������������������������������������������������������������������� 38
5.5.8.5 Clear / Clear all�������������������������������������������������������������������������������� 38
5.5.8.6 Export����������������������������������������������������������������������������������������������� 38
5.5.8.7 Quitting the program������������������������������������������������������������������������ 38
5.6 Scripts to run the LaserDiagnosticSoftware����������������������������������������������������� 39
5.7 Assessment of the Results and Error Analysis������������������������������������������������ 39
6. Review of some important Features of the GUI41
6.1 Software Menus����������������������������������������������������������������������������������������������� 41
6.2 Toolbar�������������������������������������������������������������������������������������������������������������� 43
6.3 Menu item „Measurement, Single measurement, (Measurement settings)“���� 44
6.5 Menu Item ‘Measurement, Environment’���������������������������������������������������������� 46
6.6 Menu Item ‘Adjusting Mode´ ���������������������������������������������������������������������������� 46
7. Communication
47
7.1 Test of the serial port���������������������������������������������������������������������������������������� 47
7.2 Communication between the devices��������������������������������������������������������������� 48
7.2.1 Communication - Test Responses����������������������������������������������������������������� 48
8. Maintenance and Error Analysis
49
8.1 Maintenance����������������������������������������������������������������������������������������������������� 49
8.2 Error Analysis��������������������������������������������������������������������������������������������������� 49
8.2.1 Error in data communication��������������������������������������������������������������� 49
8.2.2 No measuring signal at the BeamMonitor50��������������������������������������� 49
8.2.3 Jitter of the plots���������������������������������������������������������������������������������� 49
9. Appendix I
50
9.1 Technical Data�������������������������������������������������������������������������������������������������� 50
9.1.1 Dimensions����������������������������������������������������������������������������������������� 50
9.1.2 Weight ������������������������������������������������������������������������������������������������ 50
9.1.3 Measuring Range�������������������������������������������������������������������������������� 50
9.1.4 Power Supply�������������������������������������������������������������������������������������� 50
9.1.5 PRIMES-Bus - Assignment of the pins����������������������������������������������� 50
9.1.6 Trigger output - optional���������������������������������������������������������������������� 50
9.1.7 Dimensions BeamMonitor50 HQ��������������������������������������������������������� 51
9.2 Laserds.ini - an example���������������������������������������������������������������������������������� 52
9.3 Interface Devices���������������������������������������������������������������������������������������������� 52
9.3.1 PRIMES-Converter����������������������������������������������������������������������������� 52
9.4 PRIMES PLC - interface����������������������������������������������������������������������������������� 52
9.5 Description of the MDF File Format���������������������������������������������������������������� 53
10. Appendix II - Running LineScan (option)

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1. Laser safety precautions
Note!

The BeamMonitor50 HQ is designed to make measurements inside or near the beam pathof high power laser beams.
The device itself does not emit any laser radiation. However, laser radiation is guided
through the device and the radiation is scattered at the device.
Any user must have extensive prior technical training and possess the basic knowledge
required to perform any kind of measurement or alignment procedure of laser beamsources, beam guiding equipment or focussing devices in a safe manner.
Use of the PRIMES measuring devices like CompactPowerMonitor, BeamMonitor,
BeamMonitor50
HQ,
FocusMonitor,
LaserQualityMonitor,
MicroSpotMonitor,
PolarizationMonitor, PocketMonitor, ElectronicCalibrated-PowerMonitor or PowerMonitor
for any purpose other than the appropriate form of use specified by the manufacturer is
not permitted, and may cause bodily harm, up to and including potentially life threatening
injuries or death. The various types of monitors may not be used in a manner which may
cause a potential risk to human beings.
As stated in ISO / CEN / TR standards and regulations as described in IEC - 60825-1,
ANSI Z 136 “Laser safety standards” and ANSI Z 136.1 “Safe Use of Lasers” publishedby the American National Standards Institute and additional publications like “Laser Safety
Basics”, “LIA Laser Safety Guide”, “Guide for the Selection of Laser Eye Protection, and“Laser Safety Bulletin”, published by the Laser Institute of America (Tel: 407-380-1553) and“Guide for the Control of Laser Hazards” from ACGIH, 6500 Glenway Ave. D-5, Cincinnati,
OH 45211, when humans are present in a dangerous zone with uncovered visible orinvisible laser radiation or particularly uncovered laser beam systems, beam guiding
systems or process regions, personal protection is required. This holds true for any useof this equipment. During measurement procedures there is always an unavoidable risk oflaser radiation through direct or reflected emissions.

The proper and safe use of any monitoring device inside or nearby
the laser beam core diameter REQUIRES ALL OF THE FOLLOWING:
•
•
•
•
•
•

competent professional knowledge of the type of laser source present.
competent knowledge and understanding of the measurement device.
laser safety goggles adapted to the existing wavelength of the laser in use.
protection to reduce direct laser radiation, back reflection and associated optical radiation to a safe level.
safeguard and or emergency safety mechanisms which allow immediate closing of thelaser shutter of any free running or focused beam.
a solid mounting surface for the measurement device itself, to reduce the risk of backreflection and avoid any relative movement of the Monitor in relation to the laser beamaxis (This is also necessary to ensure the highest possible performance).

In order to comply with national and international regulations, particularly the accident
prevention regulations for use, control and alignment of high power laser beams, adequate
protection procedures and equipment are required, for example: Use of shielding screens,protective laser safety goggles, beam guiding elements and/or beam traps which do notcontain any dangerous materials that can release gases or vapors when heated.
The manufacturer and the suppliers of the monitoring equipment accept no liability fordamage or injury of any kind arising from the use of the measuring device or the associatedsoftware. The purchaser and user agrees to hold harmless both manufacturer and suppliersof any liability for injury to equipment or person, loss of business revenue, directly or
indirectly through use of this equipment.

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2. Introduction
2.1 Laser beam measurement
The observation of the laser beam parameters helps to increase the reliability of
manufacturing. The laser beam is mainly described by:••••laser power
beam dimensions and beam position of the unfocussed beam
beam dimensions and beam position of the focussed beampolarization of the laser beam

These fundamental beam parameters have a strong influence on the results of lasermaterials processing. To ensure highest processing quality, it is necessary to detect any
variation of the laser beam parameters. The variations may be induced by:••errors generated from the laser source, e.g. aging of the optical components ormaladjustment of the laser resonator
effects in the beam guiding-system or the focussing unit e.g. pollution and maladjustmentof the mirror or thermal blooming because of the existence of organic gases in thesurrounding environment.

The processing results depend mainly on the laser power and power density in the focus.
Variation of these parameters can lead to a dramatic decrease of speed and quality of theprocess. Therefore it is urgent to know the exact position and the power density distributionof the focal region.
The periodic measurement of laser beam parameters helps to make sure that the laser
beam always performs excellently as a tool. This is a basic essential for reliable materials
processing with lasers, and it ensures high quality of the manufactured products.

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2.2 PRIMES - the Company
PRIMES is a manufacturer of laser measuring devices. These devices are used to measurelaser beam parameters of high power CO2- , solide-state and diode-lasers. A wide selectionof devices is available for measurement of:
•
•
•
•
•

laser power
beam dimensions and beam position of the unfocussed beam
beam dimensions and beam position of the focussed beampolarization of the laser beam
temporal stability of the laser power

Engineering as well as production is done by PRIMES itself to provide best quality, excellent
service and a short reaction time to fulfill all the demands of our customers.

Max-Planck-Str. 2 - 64319 Pfungstadt - info@primes.de - www.primes.de

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2.3 BeamMonitor50 HQ
Laser beam radius, position and power density distribution in the unfocussed beam are ofstrong influence for the intensity in the focal plane and for any laser materials processing
results. To guarantee a reproducible processing quality, it is necessary to know and to
detect any changes.

Fig. 2.1 BeamMonitor50 HQ

The BeamMonitor50 HQ (Fig. 2.1) is a device to analyze the spatial power density
distribution of the raw beam of CO2 lasers. Results of the measurements are beam radius,
beam position and power density profile.
The BeamMonitor50 HQ is using the scanning measuring principle. Its dimensions are
adapted to the raw-beam diameter which needs a larger aperture. The BeamMonitor50 HQ
has no z-axis. Due to the availability of different detectors and measuring tips, it is possible
to use the BeamMonitor50 HQ with a wide range of wavelengths and power densities. As
standard the BeamMonitor50 HQ is configured with a pyro-electric detector. The measuring
tip is designed to work in a power density range of several kilowatts per cm2.

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2.4 What is covered by this manualThis documentation is generally for the BeamMonitor50 HQ only.
There are two principal modes of operation for the devices:•

When used to monitor automated production-processes where measurement
need to be done automatically by command of an auxiliary control, the whole
PRIMES system can be controlled via an PLC by serial communication. In thisoperational mode the user receive the numeriacal values for beam position and 		
beam dimensions.

•

When the devices are operated manually, PRIMES supplies the LaserDiag-		
nostic-Software with access to all functions of the BeamMonitor50 HQ
A graphical user interface based on Windows® makes it easy and intuitive to 		
control the devices and to visualize the results in many ways.

This documentation describes in detail both modes of operation of the PRIMESBeamMonitor50 HQ.
Remark:Please note that the software is continuously improved to meet all the demands of ourcustomers, so that there may be slight differences between this documentation and youractual software version.
If there are any questions concerning the operation of the system, please be prepared to•  give information about the software version•  the date of set-up•  the Windows® version you are working with
Please find these information within the item Help/About LaserDiangoseSoftware.

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3. Setup!

It is essential in every measurement operation
to follow the safety instructions given below.
This will allow safe and reliable operation of themeasurement devices.

3.1 Safety Instructions and Mechanical Installation
When working with the BeamMonitor50 HQ, leakage radiation can arise. The power
densities can exceed more than 100 mW/cm² of CO2-laser radiation because the beamis reflected by the surface of the measuring tip. It is strongly recommended to wear safety
glasses and to shield the measuring environment or the device carefully.
The measuring rotor of the BeamMonitor50 HQ operates at a high rotational speed.
Please avoid inserting your fingers or any other mechanical tools or parts into the beam
entrance of the measuring device. This can damage your health and / or the measuring
device.
Please take care that the laser beam is completely absorbed after passing the
BeamMonitor50 HQ. Fireclay bricks or reflecting surfaces are not suitable to annihilate
the beam energy. PRIMES provides different uncoolded, air or water cooled types of beamtraps. Nearly 100 % of the used laser beam power must be absorbed by the beam trap
during the measurement cycle.
Please mount the BeamMonitor50 HQ in a correct and stable position in the beam path.
This means that the laser beam has to pass completely in the center of the aperture. The
to be measured beam diameter should not be greater than 0.7 times the aperture. Bigger
beams might lead to dangerous reflection and a heating-up of the housing. The device
would be damaged and the measurement results might be falsified.
When mounting the BeamMonitor50 HQ, it is recommended to use screws that penetrate
the housing no further than 5 mm.
Please ensure perpendicular incidence of the laser beam relative to the x-y plane of thedevice´s coordinates. Avoid any movement or acceleration of the BeamMonitor50 HQ
during the measurement routine. Beyond the measurement routine, it is possible toaccelerate the BeamMonitor50 HQ up to the tested values of 2 g.
Please respond the manufacturer if your system could reach more than that.

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3.2 Hardware installation

Please connect the BM50 HQ via Ethernet to the PC.
Optional connect the converter’s RS232 plug to thecomputer using a cable with two female connectors.

!

If the PC is connected directly to the PRIMES-Bus, it
can be seriously damaged.
Furthermore, do not disconnect cables while thepower supply is on. This could cause harm to thecommunication circuits of the device.

The following describes the basic electrical and mechanical configuration of the system.
There are two options for voltage supply and data transfer:•

Serial / USB (option)•

Ethernet

Refer to the diagram.
Serial Interface (red):
The BeamMonitor50 HQ is connected to the
PRIMES-Bus for data communication andsupply voltage (Sections 3 and 7.2). Datatransfer is based on a RS485 bus system usinga shielded cable with two male, 9-pin, mini-D
connectors (Fig. 3.1). For communication with
the PC, the data is converted from RS485 to
RS 232 using the PRIMES Converter (Fig. 3.4).
A shielded cable with two female, 9-pin, mini-D
connectors is used for the connection between
the PC and the converter (Fig. 3.1). The
PRIMUS-Bus provides a stable supply voltage
for the measuring device as well as data transfer.

Fig. 3.1 PRIMES-Bus cable & RS232 serial cable

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USB Interface (blue):
This connection to the PC differs only in theuse of a RS232 - USB converter. This isplaced between the PC output of the PRIMES
Converter and the USB port of the computer.

Fig. 3.2 RS 232 - USB converter

Ethernet Interface (green):
The PRIMES Converter is not required if the
BeamMonitor50 HQ is connected to the PC
via the ethernet interface. The power supply
is connected directly to the serial RS485 busof the BeamMonitor50 HQ. The connection
to the computer can be direct using a crossover cable or through a network using a regular
patch-cable.
Fig. 3.3 Cross-over or standard
Patch Cable

PRIMES-Converter
The PRIMES-Converter has four LEDs todisplay the current status of the bus. They
indicate (from left to right):
red
green
		
red

bus power (24 V)
measuring device send dataon the bus
PC send data on bus

yellow trigger signal (only for service		use)Fig. 3.4 PRIMES Converter

These signals are helpful to check the system
state, especially in case of a malfunction of any
device to determine the source of misleading
signals.

Fig. 3.5 Power Supply

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Figure 3.6 shows how the BeamMonitor50 HQ is connected to a computer and power
supply using serial communication and USB converter.
To avoid any voltage drop, the power supply should be directly connected to the
BeamMonitor50 HQ using a short cable (2 m). Because data communication with RS232
is susceptible to trouble or signal corruption, the bus connection between the PC andconverter should be as short as possible.

Fig. 3.6 Set-up of the BeamMonitor

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3.3 Software installation
The PRIMES LaserDiagnoseSoftware is available for IBM compatible PCs. The software
installation is automated using a setup assistant.

3.3.1 System demands
The software requires an IBM-compatible PC (minimum: Pentium II, 500Mhz, 64MB) with
Windows® 98 or later installed and an available serial, USB, or ethernet connector.
For good performance, we recommend at least a Pentium or comparable processor with aclock frequency of at least 1 GHz. A 17-inch color monitor with 768 x 1024 pixel resolution
is recommended. The PRIMES Converter is required optional for RS485/RS232 data
communication.
If you run the system on a notebook computer, disable all power saving options in thesystem BIOS. Otherwise, you may encounter problems with serial communications duringhigh data rates.

3.3.2 Installing the Software
The menu-driven installation starts from the provided software CD.
After installation is finished, the program is launched by clicking the icon in the new program
group PRIMES.
The installation software copies the main program “LDS.exe” into the Programs folder
under PRIMES, unless another location was specified. The configuration file “laserds.ini”
is also copied to this location. This file contains the setup parameters for the PRIMES
LaserDiagnoseSoftware. An example of the “laserds.ini” file is shown in the appendix.

3.3.3 Setting up the USB-converter software (option)
Since fewer computers include a serial RS232 interface, a RS232 - USB converter is
included with the BeamMonitor50 HQ.
Installation:
1.
2.
3.
4.

Turn off the computer as necessary.
Connect the USB converter to a free port.
Start the computer.
The “New Hardware Found” window should appear.
Insert the included driver CD and select “Automatic Software Installation”.
Please note, until Windows® has installed
driver, the following message can occcur:

Fig. 3.7 Windows® - message window

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5.
6.

Restart the computer after installation is complete.
Finally, under “Device Manager”, check whether the COM port was successfully 		
installed and which number it was assigned (here COM 4).

Fig. 3.8 Device Manager Window

7.

This COM port number will be selected later in the LaserDiagnoseSoftware.

Fig. 3.9 Free Communication Window

Be sure to use the same USB port since the COM port number can change.
Further information about the converter can be found at the homepage of the manufacturer:
www.prolific.com.tw

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3.3.4 Setting up an ethernet-connection
The BeamMonitor50 HQ is equipped with an Interface for ethernet-communication. The
ethernet-communication not only enables a faster data transfer (about 1,2Mbits/s insteadof 115 Kbits/s) but also makes it easier to connect on a computer.
The BeamMonitor50 HQ can be connected on PC directly with the help of a so called“Cross over” patch cable without a secondary converter. It is also possible to use theequipment in a corporate network. The power supply is produced by the PRIMES-bus.
• Configuring an IP Address
The IP address of the BeamMonitor50 HQ
is preset according to standard on
192.168.116.85
Like that, a fast and simple directconnection to a PC with a "cross over"cable is possible.
Then it is necessary to set the IP-addressof the computer to a fixed value. Keep inmind: in standard setting, the computeror the network generates an IP-address
automatically. This standard setting may
not be useful for the operation of the BM.
This can be changed in the following way:
Within the Windows menu Control
Panel Device Manager, please selectthe sub item Internet Protocol (TCP/
IP) Properties (p.16) and click on: Usefollowing IP address and enter: IP
address 192.168.116.75 and Subnet mask
255.255.255.0
The IP-address of the BM50 HQ itself is
192.168.116.85. The first three numbersof the IP-address that you enter foryour computer must be identical to the
BeamMonitor50 HQ address, and the last
number must be different.
Now you can check and install the Ethernet
communication.
Please click on the connect button
within the menu Free Communication.
You should receive a message:
Connecting to Device 192.168.116….
CONNECTED
Then you should find the ICON of the
BeamMonitor50 HQ in the header of thesoftware.
At some computers it is necessary to restart them after changing the IP address.
If the equipment should be merged into a network, please contact us.

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3.4 Starting the LaserDiagnosticSoftwareFirst please connect all the devices properly to the PRIMES Bus and the computer. Thenturn on the power and start the software. You should see the green LED from the rear of
the BeamMonitor50 HQ and a short blink from the green LED Data light at the converter.
At start up routine, the communication on the bus will be checked and an automatic
hardware detection is performed. Symbols for all the measuring devices connected to thebus are displayed on the Toolbar at the upper right position.
Typically, the system needs 30-60 seconds after power-up or software start to detect
the initial configuration. After starting, the software scans the system for different logicaladdresses which correspond to the possibly connected devices BeamMonitor50 HQ,FocusMonitor, BeamMonitor, etc.. Attention, there is no measuring possible during thistime. During the scan there is a message box active at the bottom right of the screen.
During this software start, you should not get any error messages and the LEDs Data and
Send at the converter should blink several times. After this procedure, you should find thesymbol in the toolbar of the software. When the symbol is in the toolbar, the device is readyto start a measurement. All measurement items should be available.
An automatic measurement with the BeamMonitor50 HQ can be initiated by the PRIMESPLC control if it is connected to the PRIMES Bus. In this case, the measuring procedure isdone by a run-off-control.
Please refer to the description of the PRIMES PLC control to get more information
about this mode of operation. The next chapters show how to operate the PRIMES
LaserDiagnosticSystem manually and achieve the best measurement performance.

3.5 Power-up and Change of Configuration
Whenever the power of the BeamMonitor50 HQ is switched off and on again (power-up),
the user should run a reset cycle. The system typically needs about 30 sec to check thesystem´s configuration after power up or starting the software. If you switch on the power
supply the BeamMonitor50 HQ moves to reference position where the rotor is stored
outside the clear aperture.
Whenever the physical configuration of the devices on the bus is changed (for instance, byaddition of a further device), the user should run a rescan cycle again.
The correct installation of bus connection and communication can be checked by thewindows software (see chapter 7 Communication)!
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Do not plug or unplug any cables when the power is on !
! Connect the PC to the measurement system only via theRS232 plug at the PRIMES-Converter!

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4. Manual Operation of the BeamMonitor50 HQ
To conduct a detailed laser beam analysis, the manual mode of operation of the
BeamMonitor50 HQ is usually used. The handling of the device using the PRIMES
LaserDiagnosticSoftware is described in the following chapters.

4.1 Measurement and Presentation - a Short Description
After adjusting or mounting the BeamMonitor50 HQ in the beam path and connecting to
the power supply, PRIMES-Converter and computer, the LaserDiagnosticSoftware can bestarted.
The graphical user interface assists and guides the instrument.
The PRIMES-Bus allows all PRIMES devices
to operate without changing any physicalconnection. With several measuring devices
at the bus, it is necessary to select the current
device to run a measurement. This is done bychoosing the appropriate device name in themenu Measurement - Sensor Parameters(Fig. 4.1 and 5.2 Table)

To start a measurement select the item
Measurement - Single Measurement (Fig.
4.2). Here, the user can adjust the position
and the size of the measurement window
within the whole accessible measurement
range just by dragging and dropping theframe on the desired position.

Fig. 4.1 Measurement - Sensor parameters

For the BeamMonitor50 HQ the setting of thesize is done by the pop-up menu [ x ] when asymmetric measurement window is selected,
or by [ x ] and [ y ] for asymmetric windows. It
is sufficient to use the symmetric window formost applications.
The measurement can be started by hitting
the button Measure. When running the firstmeasurement, it is useful to select a large or
the largest measurement window to localize
the beam position.
The beam, having been located, can be
Fig. 4.2 Measurement - single measurement

analyzed accurately by selecting a small window which fits exactly around it. The Zoom
function allows the user to get a good viewof the beam.

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The presentation of the measured
results is for example done by the item
Presentation - Variable Contour Lines.
Here contour lines of the spatial power
density distribution in x- and y- directions
are shown.
To save the measured data, select File Save as in the pop-up menu.
To quit the program, select the item File
- Quit.
A more detailed description is given inchapter 5.

Fig. 4.3 Presentation - Variable Contour Lines

4.2 Operation of the BeamMonitor50 HQ
There are three important steps when operating the BeamMonitor50 HQ•••

Mechanical adjustment of thesensor-head and correct installation of the system to ensure safety with regard toleakage radiation
Performing measurements
Presentation and documentation of the measured results

4.2.1 Safety with regard to leakage radiation: Mechanical adjustment of thesensor and checking the system configuration
To assure a safe operation of the BeamMonitor50 HQ please consider the following topics
carefully
•
•

•

•
•

•
•

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Take care to get sufficient shielding of the leakage radiation and the complete
absorption of the passing beam
Check the accurate passage of the laser beam through the measuring region to
avoid reflections at the housing of the BeamMonitor50 HQ. Keep in mind, there is
only one beam entrance.
The measuring rotor of the BeamMonitor50 HQ operates at a high rotational speed.
Please avoid inserting your fingers or any other mechanical parts into thebeam entrance of the measuring device.
This can damage your health and / or the measuring device
Provide a perpendicular incidence of the laser beamInspect the electrical connections between the system’s components.
The PC has to be connected only to the RS232 plug of the PRIMES-Converter.
Any other connection of the serial interface of the PC to the system candamage the computer. Also Ethernet connection is possible (option)
Hard- and software requirements
Check the communication between the computer and the measuring devices
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4.2.2 Performing measurements
There are two possible ways to perform measurements with the BeamMonitor50 HQ.
•Single measurement (manually or automatically adjusted): The position and the 		size of the measurement window can be adjusted relatively to the whole measu-		
ring range. A false color presentation is possible.

•

Adjustment mode
Special Measuring mode of the BeamMonitor50 HQ is used for resonatoradjustment or laser servicing. This mode of operation is characterized by a simple
handling and a clear presentation menu.
The results of the single and the serial measurements are presented in different 		
plans or in special presentations.

4.2.3 Presentation and documentation of the measured results
The PRIMES LaserDiagnosticSoftware offers the following features for visualization,
analysis and storage of the measured results:

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3-D Presentation (Isometry) of the spatial laser power density distribution•

Contour lines in false colors of the spatial laser power density distribution•

Variable contour lines of the spatial laser power density distribution. Eligible are 		
contour lines in x-, y-direction or power density coordinates.

•

Fixed contour lines in x-, y-direction at 86%, 80%, 60%, 40%, 20% and 10% of 		the total power•

Symmetry check (not standard application)•

Review - the following parameters are displayed numerically: date, time, radius, 		radius in x, radius in y, angle, position in x, position in y, laser power density, laser 		power, etc.

•

Graphical review of various beam parameters•

Export of the numerical measured values after measurement into a tab-separated 		
text-file, readable by Microsoft Excel•

Every measurement is stored in its own layer. The layers can be combined to 			show the caustic, e.g. when using a FocusMonitor•

Storage of numerical values - beam radius and position - to file or to database.

•Storage of measured data to disk•

Storage of the current settings/preferences to disk•

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5. The Operation of the LaserDiagnosticSoftware
Please note that some of the essential windows of the graphical user interface (formeasuring and communication) always stay in the foreground. All the presentation windows
will be overwritten, when a new window is opened.

5.1 Logical Structure of the Graphical User Interface
The graphical user interface consists of four main subjects:•

Measuring
All the settings for single and serial measurement can be done here. The size 		and position of the measurement window can be adjusted. The spatial resolution,
the rotational speed and the number of cases for averaging can also be selected.
It is possible to adjust the parameters automatically and store them to disk.

•

Presentation
The presentation features cover all matters needed to gain maximum informationfrom the data and to classify the measured results. Available are false color 		
presentation, isometry, variable and fixed contour lines and as an additional 		feature detailed symmetry checks. The numerical values of the results can also 		
be displayed.

•

Data Administration
The saving and loading of all measured data and measurement settings, high-		
resolution printout protocol, export and a copy function are included.
All windows could be copied to any other windows file simply by copy and paste 		functions.

•

Communication
To control the communication on the PRIMES-Bus. This item is necessary to 		adjust the devices and do troubleshooting.

For parallel handling of several sets of measured data, it is possible to store the results of
up to 20 single measurements in one file. Every measurement is written in an single image
storage, called plane. Different planes can be used for variation of parameters, such as
power or time. It is possible to compare and analyze different planes as well as data fromdifferent files.

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5.2 The Graphical User Interface
The PRIMES-LaserDiagnosticSoftware has a graphical user interface. Different windows
can be opened simultaneously. This means that it is possible to open different presentation
menus at the same time. Most of the handling can be done by mouse clicks. Often numericalinput from the keyboard is also possible.

Fig. 5.1 Menu bar and the menus of the ‘LaserDiagnosticSoftware’

A detailed description of all menus is given in chapter 6.

5.3 Adjustment of parameters for measurement
It is possible to operate different measuring devices on the PRIMES-Bus. The device
to measure with has to be selected. This is done in the menu Measurement - Sensor
Parameters (Fig. 5.2) or in the Toolbar.
An assignment of devices’ names to the logical addresses is shown in Table 5.1.
When only one measurement-device is connected to the PRIMES-Bus no selection isnecessary.

Tabel 5.1 Table Device assignment

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The pull down bar Measurement - Sensor Parameters is also used to select the numberof tracks and the number of pixels per track. Thus the spatial resolution of the measurement
can be controlled from 32 x 32 up to 256 x 256 - normally 64 x 64 pixel is sufficient.
The cycle - time a measurement needs increases with the number of pixels and tracks,
because a higher resolution causes more data to be transferred and displayed. When using
the normal spatial resolution of 64 x 64 pixels the measurement time is about < 5 seconds.
The setting of mechanical limits is not
relevant for the BM50 HQ.
When the device is connected to the PC,
the LaserDiagnosticsSoftware automaticallyselects the correct detector type. A manual
selection is not possible.
The rotational speed is set to a fixed value.

Fig. 5.3 The Item Measurement - SensorParamter

If the user wishes to run a caustic measurement it is possible to enter z-values for every
measured plane after clicking the button Manual z-axis. Then the z-position can be varied
manually, for instance any axis of the laser machine can be used. The movement values
are entered manually in the menu Single Measurement and the software can calculate on
this basis the beam propagation factor in the caustic presentation. This feature can also
be used to calculate the beam propagation ratio from raw beam measurements at different
distances.

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5.4 Measuring
5.4.1 Single Measurement
Here the user can adjust the position and the size of the measurement window within thewhole accessible measure-ment range. The adjustment of size is done by a pop-up menu
with [ x] for quadratic or [ x ] and [ y ] for rectangular windows.
The maximum size of the measurement window for the BeamMonitor50 HQ is 36 mm, resp. 48
mm. The position is controlled by dragging and dropping the window with the mouse.
					
				
The slider Power serves to set theactual laser power for the softwarealgorithm to calculate the spatial
power density. It can be adjusted toany power up to maximum. Maximum
power is entered by choosing
Measurement - Environment.
One set of measurement dataconsists of up to 20 single power
density distributions which are
stored, each for a designated plane.
The results can be compared andanalyzed easily by using the various
presentation features of the PRIMES
LaserDiagnosticSoftware.

										Fig. 5.4: The item Measurement - Single Measurement

During the activity of the system different messages are displayed on the information box
at the bottom right of the screen.
During initialization the query demands on the various devices and during measurement
the status of the system is displayed. The window displays•

the current measuring plane•

the referencing of the device•

the positioning of the device•

the procedure of measurement•

the transfer of data to the computer•

the number of cases for averaging

Use the button Cancel to stop the running measurement if any problem or collision occurs.
Cancel also stops the monitoring mode. Stop stops the measurement. Afterwards, a reset
cycle should be run before the next measurement.
The button Copy allows the process to take over the settings of measurement window size,
power and amplification settings from the previous plane. The settings are copied from theplane with the next lower number.

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Averaging of measurements is an important feature to eliminate temporal fluctuations of thelaser beam and to reduce the noise inherently included in every measurement.
Laser exitation frequencies might be visualized in the measurement file. The number ofcycles to average over (up to 50) can be chosen by the roll-down menu.
There are different modes of averaging available:
Mean value
Max. Pixel
Max. Tracereal average.
hold the maximum value of pixel during measurement, andhold the maximum value of trace during measurement.

Max. Pixel and Max. Trace can be helpful when detecting pulsed laser radiation.
The item Max. Pixel can lead to some problems with the determination of the beam radius.
This is due to a problem with this mode of operation when calculating the zero level. If thezero level is falsified in this mode of operation, then the calculation of the beam radius will
fail. The button Stop terminates the rotation of the measuring tip.

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5.4.2 Environment
This item is to add information about the measurement
and specific comments. This will be displayed later on in
the Presentation - Review.
Laser Power is a reference value for the exact adjustmentin the item Single Measurement.
The wavelength value can be selected - necessary forthe correct calculation of the beam propagation factor.
Available are the wavelength of 10.6µm for CO2 laser
radiation, 1.06µm for Nd:YAG laser radiation and
0.632µm for HeNe laser radiation. The default value is
10.6µm for CO2 laser radiation.
With the item actuate it is possible to make changes inthe environment setting after the measurement.Thesechanges do not change the original file but could be
stored under a new file name.
							Fig. 5.5 The item Measurement 									Environment

5.4.3 BeamFind Settings
Setting for the Beam Find algorithm can be done byselecting:• the spatial resolution in the x- and y- directions.
The distance should be much smaller than the
expected beam diameter. When running the
BeamFind with 8 x 8 mm window and a resolutionof 64 x 64 pixels the distance between the pixels isin the range of 120µm. In this case it is difficult tofind very small beams. In this case the resolution
has to be increased.
• Trigger - depends on zero level of the measuring			 system
Fig. 5.6 The item BeamFind Settings

Trigger and Percent in the BeamFind item
First we define the zero-level. The typicalvalue for the zero-level of our standard
BeamMonitor50 HQ detector is 300 ADcounts (ADC) at 12 Bit. It is the offset ofthe detector. On this zero-level you willfind, depending on the type of detector,
a noise ratio of 2 (12 Bit) counts with thepyro-electrical detector and around 5
counts with the photo-detector.

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5.4.4 Protocol
With this item the User can write measured data directly
to a text file.
Written results are:•Date and time of the measurement•

beam position and beam radius (86% and 2nd
Moment definition)

How to activate ?:						Click on the button Write.
Now the User can enter the filename directly or via Browse.

The system is then ready for writing to the database.
														

							

Fig. 5.7 The item Protocol

5.4.5 AdjustMode
This very special feature is made for the adjustment of laser resonators with the
BeamMonitor50 HQ The parameters displayed are the symmetry of the last measured
power density distribution, radii and positions.

Fig. 5.8 The Measuring Panel of the AdjustmentMode

The typical measuring procedure starts with a FindBeam. After this please start with
Continuous Measurement. The results are written one after another to the planes
numbered from 0 to 19 (after plane 19 plane 0 is overwritten).
Users can choose between two modes of visualization by using the corresponding buttons
in the window.
In the first mode Measuring Panel, the false color presentation of the two latest
measurements are displayed, combined with the numerical values of beam position andbeam radius

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The second is the Adjustment Panel, which concerns the latest three measurements
Here the symmetry of the laser beam at different power levels is checked (see also chap.
5.5.5), the ratio of Rx and Ry is calculated (according the 2nd order moment method),
and the volume of the power density distribution is determined (a relative degree for laser
power). The results are displayed with squares in different colors as well as numerically.
Green (or gray, in black-and-white images) corresponds to minimum variation from circularsymmetry and red (or dark gray) to maximum.

Fig. 5.9 The Adjusting Panel of the AdjustmentMode

The measured results can be documented automatically either by writing the beam radius
and the measured beam position to a protocol file using the protocol button (chapter 5.4.5)
or by saving the entire measured data using the document button.
The time-interval between two measurements can be assigned if necessary in the
document menu.

Fig. 5.10 Document window

The report button allows results such as service reports (chapter 5.11) to be saved andprinted later.The name of the technician or the company name can also be saved in thesettings file laserds.ini.

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Fig. 5.10 Example of a report page

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5.5 Presentation and Documentation of Measured Results
This item describes the visualization and analysis of the measured results and storage ofthe data.
The Toolbar

It is possible to display different sets of beam diagnostic data with the PRIMES
LaserDiagnosticSoftware. Thus the User gets the opportunity to compare measured datawith previously recorded data saved on file. The opened files are displayed in the Toolbar.
To open a presentation menu a file in the Toolbar must be selected.
In the header of the presentation window the name of the data file is displayed.
In the Presentation items Variable contour lines, Isometry and False color the button
Autoscale allows one to use the whole dynamic range of the display for visualization. A
special feature is the SymmetryCheck as an additional analyzing-tool.
Moreover, the item Planes allows switching between different measurement planes. By
moving the cursor up and down, the User can switch between the planes, provided the
button has been selected with the mouse. By setting the plane selection in the Presentation
items to global, the selection can be controlled by the setting in the header.
The header of the presentation window displays the name of the presented file.
Explanation of the new features - For the items 5.5.1 – 5.5.4 there are some additionalfeatures
1) Pixel scale: This item is only important if you a measuring with no square windows size.
For instance: 0.375 mm in x – direction and 0.187 mm in y – direction. If you click in thiscase on pixel scale you will get a presentation according to the pixels not longer to thephysical dimensions of the window. Please have a look on the examples.
2) Windows scale: This item scale all the results within one data set to the maximum
measuring window which was used. This should help the user to have a better comparison
between the results in the various planes.
3) Scale of density: This item scale all the results within one data set to the maximum
power density which was measured. This should help the user to have a better comparison
between the results in the various planes.

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5.5.1 Contour lines
5.5.1.1 Free variable Contour Lines
This presentation shows free adjustable contour lines of the spatial power density distribution.
There is a choice between contour lines inthe x- and y-direction and power density
coordinates. The selection of the contour
lines can be done by the mouse or by the
keyboard. To select different contour lines in:−x - direction:press the key x
to increase and <shift> x to 		decrease the value.

−y - direction:press the key y
to increase and <shift> y to 		decrease the value−

Power density (Intensity): press the
key i to increase and <shift> i todecrease the value.

Fig. 5.12 The item Presentation Free Variable Contour Lines

The x-, y- and power density-coordinates can be selected using the sliders: The message box
in the upper right area of the window shows the actual values represented by the triangularsliders. The range of the x and y contour lines is from zero to the selected measuringresolution in pixel-coordinates. ADC-Counts contains the power density information inabsolute counts of the AD-Converter. The maximum value is 4095 Counts.
Also displayed are the spatial resolution in pixel coordinates, the size of the measurement
area in mm, the amplification, the number averaging and the rotational speed.

5.5.1.2 Fixed Contour Lines
Contour lines at different power levels
are displayed. Contours at:
86%, 80%, 60%, 40%, 20% and 10%
are selected.
In this presentation mode it is also
possible to measure distances byclicking with the mouse on the screen
at the start and end of the desired
range.

Fig. 5.13 The item Fixed Contour Lines

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5.5.2 Isometry (3-D Presentation)
Generates a 3-D presentation of themeasured distribution of laser power
density. With the roll-down-menu Plane itis possible to switch between the different
measurement planes. The button False
Color allows to switch between colored andblack-and-white presentation.
The button Pixelscale allows the user toswitch between real spatial coordinates andpixel coordinates.
The viewpoint can be rotated by the button
Angle in steps of 0°, 90°, 180° and 270°.

5.5.3 Pseudo colors
Displays a pseudo-color representation of
the measured power density distribution.

Fig. 5.14 The item Presentation - 3D Presentation(Isometry)

The color scale is shown on the left. For
higher sensitivity, for example - analysis of diffraction figures, the color scale can bechanged under the menu item “Presentation - Color Tables.” There are three scale modes
in addition to automatic scaling.
Scale on Density Scaling:
All planes of the caustic measurement
are scaled to the highest measured power
density. This should help better compare
the individual planes with each other.
Pixel Scaling:
This scaling can be used when you haveunsymmetrical measuring windows or
unsymmetrical spatial resolution (forinstance 128x64). The display is no longer
a function of measurement window size, butof the number of measured pixels.
Window Scaling:		Using this scaling, all measurement
windows of the caustic measurement are
resized to the largest measurement window.
Fig. 5.15 The item Presentation - False Colors
This scaling should also help compare to
the individual planes of the caustic measurement better with each other.
			

5.5.4 Symmetry Check
An important feature for presentation is the symmetry check. It is available as an additional
function of the Software.
This feature checks the rotational symmetry of the power density distribution of the laser
beam. It can be used for laser adjustment purposes in combination with the Monitor featureincluded in the PRIMES LaserDiagnosticSoftware.
The following figures 5.16 to 5.19 show two examples for possible results of the SymmetryCheck
which are:
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an elliptic beam•a beam with rotational symmetry over a cut at 86% of
maximum power

The displayed power density distribution of an elliptic beamleads to the following results of the SymmetryCheck.
The x-axis represents the angle and the y-axis the radius which
includes different cuts between 86% and 10% of the detected
maximum power.
On screen the curves have different colors. The radius is givenin pixel values. Minimum and maximum of the radius values
can be selected. On the right side the standard deviations of the displayed radius lines areshown. These values give precise information about the symmetry of the measured beam.

Fig. 5.16 SymmetryCheck in Cartesian Coordinates

Fig. 5.17 SymmetryCheck in Polar Coordinates

Well adjusted resonators reach standard deviations in the range of 3 % to 5 %A presentation in polar coordinates is also possible (Fig. 5.17). The displayed graphs include
86% to 10% of the detected power.
On screen, the graphs have different colors. The x- and y-axis are given in pixel values.

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5.5.4.1 The Algorithm
For the SymmetryCheck the estimated regions are 86, 80, 60, 40, 20 and 10% of the
maximum measured laser power density. For the 86% - area the moment of inertia iscalculated. This is the center of the whole SymmetryCheck. Then a scan is made to obtain
the radius and the angle valuesof the different power levels.
Results are pairs of radii andangles. The maximum values forthe radii are finally connected bystraight lines.
For the 10% and 20% regions
there are often (with a resolutionof 64x64 pixel) only a few points
left, so the standard deviation
value becomes quite uncertain.
In the SymmetryCheck presentation the minimum of the
TEM10* - mode cannot be seen.
				Fig. 5.18 SymmetryCheck in
Cartesian Coordinates

A presentation in polar coordinates is also possible (Fig.
5.17). The graphs including
contours from 86% to 10% of thedetected power are displayed
there.
On screen the graphs havedifferent colors. Values x-and
y-axis are given in pixel numbers.
					Fig. 5.19 SymmetryCheck in Polar
Coordinates							

5.5.5 Color Tables
It is possible to choose a different color table. The relation
between the measured power density and the color circle
is changed. This is relevant for any false color presentation.
Three tables are used:
1 - linear color table2 - square root color table3 - fourth root color table
This feature can be used for instance for better visualization of a diffraction pattern.

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5.5.6 Review - 86% and 2nd Order Moments

Fig. 5.20: Menu Item “Display - Review (86%)”

The following parameters are displayed:date of measurement, time of measurement, as well as the entries from the menu item
“Measurement - Environment”: focal length, offsets, and contents of the comment field.
In addition, the following numeric results are displayed.
Beam radius, x beam radius (only for 2nd moments - principle axis), y beam radius (only for2nd moments - the minor axis), x-position, y-position, and, where appropriate, z-positionand power density (based on the power rating settings in the “Measurement” menus).
The difference between overviews is that one presents results based on the 86% power
distribution and the other on the 2nd moment in accordance with ISO 11146.
When measurement signals are close to the null level, the results are displayed in gray, notblack. In this case, you must verify if the results should be rejected and the test repeatedwith different settings. The entry power, focal length and wavelength in the comment line canalso be changed after a measurement. This is done using the menu item “Measurement- Environment.”

Fig. 5.21.: The item Measurement - Review 2nd Order Moments

When the measured signals are close to the zero level, the results are greyed in the
Review-window. In this case you should check carefully, whether the calculated values
should be rejected and the measurement should be repeated with different settings.
It is not possible to make any changes in the Review.
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For making comments, the sign ‘#’ should not be used. This would lead to serious
problems when storing the data.

5.5.7 Graphical Review
The Graphical review enables the user to do various presentations. He can select for they-axis: radius, position x and y and the angle and for the x-axis: power, time, plane and zposition. It is possible to receive 16 different graphs.

Fig. 22 Graphical Review

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5.5.8 Data management
Further functions are available for organizing the measured data and the settings of thedevice5.5.8.1 Storing and reloading of measured data
To store the measured data to file, the item File - Save as has to be used. The user canchange between different formats of data storage. The standard type is binary storage,
which needs a minimum of storage capacity. The extension for these data files is ‘.foc’.
Alternatively it is possible to store the data into an ASCII format with the extension ´.mdf´More information about .mdf is given in the appendix. Only files with these extensions canbe opened by the PRIMES LaserDiagnostic Software. To open a file of measured data go
to the item File - OpenStored data can only be reloaded easily, when thefile has the extension ‘.foc’ or ‘.mdf’. Measured
data are displayed only when the desired file isselected in the Toolbar.
Fig. 5.23 reloading of measured data

5.5.8.2 Storing of Preferences to file, and opening of such files
To store the current Preferences (i.e. parameter-settings for the measurement) to file, themenu File - Save Preferences is to be used. To reload the stored preferences go to themenu File - Load preferences. The standard extension for the preferences files is ‘.ptx’.
5.5.8.3 Printing
The item File - Print serves to print the actual selected window. The adjustment of theprinter is done by File - Printer settings.
To check the layout of the prints the function Print preview can be used.
5.5.8.4 Copy
With the item Edit - Copy it is possible to export graphics to other programs on the PC. The
current window is transferred to the Clipboard.
5.5.8.5 Clear / Clear all
With Clear or Clear all it is possible to reset the contents of one plane or all planes whichis/are selected in the Toolbar.
5.5.8.6 Export
This item writes the numerical results into a tab - separated text file. This file can easily be
imported to Microsoft Excel.
5.5.8.7 Quitting the program
To quit the program, select the item File - Quit.

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5.6 Scripts to run the LaserDiagnosticSoftware
To run automatically a complex measuring procedure, it is helpful to use the PRIMES script
generator. Detailed information about programming is provided. As an example, a script for
the BeamFind procedure of the BeamMonitor is displayed (Fig. 5.24).

Fig. 5.24 Script for Beam Find Procedure

To open the script-file press the Open-symbol. Then choose a file; the script can be run bypressing the- button . The- Button stops andclose the script.

5.7 Assessment of the Results and Error Analysis
For the correct interpretation of the measured data and the classification of the calculated
results, it is important to know some specific features of the measuring devices.
Radius definition - detailed information is available.
The program uses two alternate radius definitions.
86% - definition:
The radius of the laser beam is calculated by estimating the beam area containing 86% of
the total measured laser power. This value allows one to determine the radius of the circle
with the same area.
This definition is valid only when the laser beam is rotationally-symmetric and there are noareas with deep modulation of laser intensity (very low laser intensity) in the beam area.
Second order moments - definition:
The radius of the laser beam is calculated from the second order moment of the power
density distribution - as in ISO 11146.
Sometimes it may also be helpful to determine the beam radius according to the 10-90%
signal rise from the Contour lines Presentation.

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Beam position in the measurement window
The position of the measurement window has to be selected so that the whole beam fits
in the window. This is the basis for a correct calculation of the beam radius and beam
position.
Size of the measurement window
To minimize the measuring uncertainty it is necessary to select an appropriate size of themeasuring window. Windows that are too small or too large lead to increasing errors. The
beam radius should be between 15 and 35% of the base line of the quadratic measuringarea.
Temporal Stability
The BeamMonitor50 HQ is mainly designed to measure continuous wave laser radiation.
Temporal fluctuations of the laser power or of the spatial power density distribution cannot
be detected efficiently, if the time constants of the variations are smaller than the measuring
time of about two seconds.
Repetitively, pulsed laser radiation can be detected, but interference between the laser
frequency and the scanning frequency of the BeamMonitor50 HQ may occur.
In many lasers the setting of laser power is done by the modulation of the pulse-width(usually in high frequency excited lasers), which sometimes leads to modulation of thelaser power. This can influence the measured results. In rare cases interference between
modulation and measurement frequency can be observed. Changing of the spatial
resolution changes the rate digitizing (measurement frequency), and may help to avoid theinterference.
Transmissive optics (for instance outcouplers and lenses) usually show a temporal variationof the optical parameters after incidence of high power laser radiation. It takes typically 1020 seconds until the optics reach their thermal equilibrium. During this time the refractive
index and thickness of the material changes. Normally these effects lead to a variation of
the diameter and the divergence of the laser beam.
If necessary the measurement should be started after the critical time.
To measure temporally modulated beams, it helps to activate the averaging mode or tosynchronize the laser on the motion of the measuring tip.

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6. Review of some important Features of the Graphical
User Interface
6.1 Software Menus

Fig. 6.1: The Menu Structure
FileNew 			to open a new file for measured data
Open			to reload a file of measured data with the extension ‘.foc’.
Close			to close the file which is selected in the Toolbar
Save			to save a file
Save as			to open the menu for saving the file which is selected in the Toolbar.
				Only files with the extension ‘.foc’ can be reloaded
Load preferences		
to reload a file defining preferences with the extension ‘.ptx’.
Save preferences		
to open the menu to store the preferences of last program run.		
				
Only files with the extension ‘.ptx’ can be reloaded
Export			to save the file as ´.pkl´ (protocol)
Protocol			To start a protocol written to file or to database
Print			starts a standard printing menu
Print Preview 		
shows the expected result of the print job
Exit			terminates the program
Edit
Copy			Clear plane		
Clear all planes		

copies the current window to the clipboard
deletes the data from the plane which is selected in the Toolbar
deletes all the data from the file which is selected in the Toolbar

Measurement
Environment						
Sensor Parameter						
Beamfind Settings		

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here several system values should be entered:
For details, please see chapter 6.6
the settings of the devices can be adjusted here:
For details, please see chapter 6.4
To adjust the parameters for the BeamFind algorithm

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Single Measurement
				
				

this item is used to run a single measurement or to start the monitoring
mode. The adjustment of the measuring window is done here. For
the FocusMonitor an automatic Beam Find algorithm is available.

Caustic Measurement
		
		
		
		
		
		
Start Adjust-Mode				

to run a caustic measurement using the FocusMonitor. When the manu
ally adjusted mode is selected, all the current settings of the planes areused for the measurement. The automatic measurement starts withFind Beam and runs the whole measurement process automatically. Only the measuring range in the z-axis and the number ofplanes to be measured have to be entered.
This item is not relevant for the BeamMonitor50 HQStarts a special mode of operation of the BeamMonitor 50HQ for an 		easier adjustment of the laser resonator
For details, please see chapter 6.6

Presentation
False color 		
false color presentation of the spatial power density distribution
Isometry 			three dimensional presentation of the spatial power density distribution.
Review (86%)		
numerical review of the measured results of the different planes						
based on the 86% beam radius definition
Review (2nd Moments)
based on the 2nd order moments beam radius definition
Caustic			
results of the caustic measurement and the parameters of the calcula				ted fitting curve - which lead to beam propagation ratio, focal position				and focal radiusSymmetryCheck		Analysis tool to check the beam symmetry especially for laser 						adjustment purpose. Available as an additional feature.
Fixed Contour lines		presentation of the contour lines of the spatial power density 						distribution at six fixed power levels
Var. Contour lines		presentation of free variable contour lines of the spatial power density 						distribution
Graphical Review		
enables different presentations - for instance radius, x- and y-position 						versus z-position or time
Color Tables		Different color scalings for the detailed analysis for instance of diffrac		
				tion phenomena.
Toolbar			to display or hide the Toolbar
Focus Position
moves horizontal carrier to the measured focal position
Park Position
moves horizontal carrier to the z-axis zero position
Communication
Rescan bus		
to re-run the hardware detection - necessary when the device configu-						
ration connected to the PRIMES-Bus has been changed.
Test 			checks if the bus-lines are free for transmission or if a fault has occur-						redSend frame		
here the communication on the bus can be checked in detail. All the 						
devices can be polled by the PC.
Port			allows the User to select one of the communication ports available on 						the PC.
		
If only one port is available it is automatically opened by the program.
Close Port 		to close the serial port
ScriptEditor			
List 			opens the script editor, a tool to run complex measuring scripts.
displays the open windows

Help
Hints							Revision 01/2015 EN

displays additional hints depending on software version and hardware 		
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6.2 Toolbar
By clicking the icons shown in the Toolbar the different software menus can be opened
directly.

1

2

3

4

5

6

7

8

9

10

11

1 - Create a new set of data (file)
2 - Open an existing file
3 - Store a file
4 - Open Presentation - Isometry for the selected set of data
5 - Open Presentation - Contour Lines for the selected set of data
6 - Open Presentation - 86%-Review for the selected set of data
7 - Open Presentation - False Color for the selected set of data
8 - Open Presentation - Caustic for the selected set of data
9 - List of files for selection
10 - List of planes for selection
11 - Symbols to select the devices - when different devices are present at the bus
All measured results are written to the file selected in the Toolbar.
Only data from the selected file can be displayed.
After opening a file it has to be made the current file by choosing it in the Toolbar.
Only the device that is selected is ready to measure!

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6.3 Menu item „Measurement, Single measurement, (Measurement
settings)“

1
2- Measurestarts a measurement in the currently selected plane- Monitor 		
starts the monitoring mode - automatic repeat measure 			
		
mode
3
- Stop 		stops the mechanical motion of the device
4- Reset 		
resets the system
5- Exit 		closes the window
7- Plane 		to switch between the different image stores (0-19)
8,9- z-position
not relevant for the BeamMonitor50 HQ
10,11 - Power 		
recommended slider or by numerical input
12,13 - Amplification
not relevant for the BeamMonitor50 HQ
14- Find Beam
not relevant for the BeamMonitor50 HQ
15- Averaging
variable number of measurements for averaging. 						Different modes are available: mean value, maximum of 					
pixel and maximum of plot
16
- Copy		to take over settings from the previous plane into the 						current plane (for instance when plane 3 is selected, 						copy takes over the setting from plane 2)
17- FalseColor
The display can be changed to false colors. The color 				reference is given in the item Presentation/Color Table
18- Symmetric
Forces the system to use quadratic measurement areas. 			
		
Rectangular areas are possible.
19- Zoom 		to select different zoom-factors to get better adjustment 					
of the measuring area on the beam.
20- Size of the measurement window		
For BeamMonitor50 HQ and the Monitor the scale		depends on the aperture21- Display for measured results
		The square shows the current measurement window.
22- Signal saturation		
The degree of signal saturation is displayed. When the signal 					
reaches 4095 ADC, the spot becomes red.
23
- Optimize
Only for MicroSpotMonitor

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6.4 Menu Item ‘Measurement, Sensor Parameter‘

1 - Device		Selection of the device when operating two or more devices at			the PRIMES-Bus: BeamMonitor50 HQ or BeamMonitor,
			FocusMonitor or MicroSpotMonitor
2 - Rotational speed

The BeamMonitor50 HQ is runinng at a fixed speed of 2112 rpm.

									3,4 - Spatial resolutionin x-direction by the number of pixels per trace -32, 64, 128, 256			

in y-direction by the number of traces - 32, 64, 128, 256

5 - Limits of Motion

not relevant for the BeamMonitor50 HQ

6 - Exit

will close this window, otherwise it will stay in the foreground.

7 - Setting of the mechanical limits
			not relevant for the BeamMonitor50 HQ
8 - Manual z-axis

Manual z-axis removes the connection between the z-axis
adjustment in the single measuremet display/window andthe mechanism of the motor.

9 - Detector type

When the device is connected to the PC, theLaserDiagnosticsSoftware automatically selects the correct
detector type. A manual selection is not possible. .

10 - Twisted tip:

not relevant for the BeamMonitor50 HQ

11 - Radius correction: Activates the smoothing of the curvature of the scanned traces 			
option.
12 - Temporal:

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Allows measurement at a fixed y-position to check the temporal 		development of the power density.
Please have a look also to Appendix III - Line scan.

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6.5 Menu Item ‘Measurement, Environment’

6.6 Menu Item ‘Adjusting Mode´

Find Beam 		starts an automated beam find procedure
Single 		starts a single measurement
Continuous 		
starts a continuous measurement
Protocol 		starts the protocol - writing the calculated beam data to file
Document		
opens a document - writing the measured data with all the pixel 					information to file>> Adjustment Panel switch to the other presentation panel of the adjustment mode
Report 		prepares a text document for measurement report

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7. Communication
When a communication problem occurs, the menu Communication in the header line will
provide help. It allows the user to check the communication between the PC, the BeamMonitor
50HQ, the FocusMonitor and all other PRIMES devices. The item Communication - Port
allows the user to select one of the available serial ports of the PC. The item Close port
terminates the assignment of the software to the port.
The item Communication - Test is to check whether the PRIMES-Bus is available. The
PC sends a signal and waits for an echo. This echo is generated by the PRIMES-devices.
When there is no echo the bus has to be checked.

7.1 Test of the serial port
When the PRIMES-LaserDiagnosticSoftware is started the serial port is tested at first.
Possible error message:

It means that the Software could not open the serial port of the PC.
Possible reasons are:•Another program is running and using the serial port. This could
be Fax- or Modem-Software•

The program is trying to open the wrong serial port. The serial port can be selected with the item Communication - Port. All available ports are displayed.

The file laserds.ini in the Windows folder determines which port will be selected whenstarting the PRIMES-LaserDiagnosticSoftware. An example is given in the appendix.
Workaround:•
Quit the LaserDiagnosticSoftware•
Change the port setting in the Laserds.ini and save•Start the Software again.
When the user wishes to run a program which needs access tothe serial port while working with the LaserDiagnosticSoftware it ispossible to close the port with the item Communication Close Port.
Possible error message:
The message means that there is no communicationon the bus so that the connected devices could notcommunicate.
Possible reasons are:•

The devices are not connected in thecorrect manner (refer to chap. 2)•

The power supply is off.

Workaround:•

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restart the system by switching the power off and on.
After a system-reset the parameters of the connected devices are read. This canbe seen in the control box button visualized at the lower right screen position.
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7.2 Communication between the devices
The communication of the devices connected to the PRIMES-Bus can be tested. Every device
on the bus has its own address. With the item Communication - Free Communication it
is possible to check the links to the devices.

To test the communication of the devices send a test request from the PC to the device byusing the item Communication - Send Frame.
This is done by entering the address of the sender (always 64 for the PC), address of therecipient and a message. Then click the Send button.
The device should reply as described in table 7.1. For the test it is important to use exactly
this form of writing - do not type ‘QR’ or ‘query ready’. Do not use the Enter key on the
keyboard.

7.2.1 Communication - Test Responses
Device: From:

Address:

Test request

Answer

BeamMonitor50 HQ
BeamMonitor
PowerMonitor

64
64
64

152
144
112 or113

qr
qr
qr

alD BeamMonitor50 HQ
aID BeamMonitor
ready Power Monitor

Table 7.1 Communication-Test Responses

If no message appears on the screen there may be a problem with the communication.
Switch off the power supply for the LaserDiagnosticSystem and check the cable connections
between the devices in accordance with chapter 3 . Verify that all connectors are plugged-incorrectly. Then switch the power on and test again.
Possibly the PC is not configured correctly. This can be seen at the third LED (red) of the
PRIMES-Converter. It is connected to the RTS-signal of the serial interface. When the LED
is glowing steadily no data transmission is possible. Try to reopen the interface by selecting
Communication - Port or restart the PC.
When the communication works properly you can open the item Measurement - Single
Measurement and proceed with the measuring procedure.

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8. Maintenance and Error Analysis
8.1 MaintenanceNo maintenance is necessary for the device under normal operating conditions.
In a very dusty environment it could be useful to clean the mechanical guiding mechanismwith isopropanol and to grease the mechanical guiding mechanism and the ball screw
slightly over.

8.2 Error Analysis
When any error occurs check first whether the system installation is correct (chap. 3).

8.2.1 Error in data communication
When there is an error in data communication (indicated by a grey button Measurementin the item Measurement - Single Measurement ) it may be helpful to reset the system byswitching off/on the 24V power supply and to reboot the computer.

8.2.2 No measuring signal at the BeamMonitor50 HQWhen there is only noise signal on the screen - typically around 800 AD-counts in
Presentation - Variable Contour Lines - check:•the device’s position and orientation (chap. 3).
Does the beam enter the correct side of the device?

8.2.3 Jitter of the plots
When measuring small beams sometimes a jitter between the different plots of themeasured power density distributions is observed.
This jitter is due to small fluctuations in the speed of the rotational drum and the stability of
the generation of the trigger signal. The jitter of the traces can be minimized by choosing
a beam position strong on the left side of the measuring window. So the temporal distance
between trigger signal and the start of the measurement is small and any disturbance canbe reduced to a minimum.
Please keep in mind there might by also temporal fluctuations coming out of the laser
source. They are detected by the BeamMonitor50 HQ due to the high band of the detector.

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9. Appendix I
9.1 Technical Data
9.1.1 Dimensions
The dimensions without connected plugsof the BeamMonitor50 HQ 50 mm are: 182 x 139 x 68 mm

9.1.2 Weight
The total weight of the device is 1500 g

9.1.3 Measuring Range
BeamMonitor50 HQ
Measurable Power range			
The maximum power density				
Clear aperture (CA)		
		
Maximum beam diameter to be measured: 		up to 10 kW< 10 kW/cm²
50 mm
35 mm (depending on M2)

9.1.4 Power Supply
The operating voltage of all devices connected to the PRIMES-Bus is DC 24V ±5%.
Input current for the BeamMonitor50 HQ is 0.7 A - maximum.
Stand by current for the BeamMonitor50 HQ is 120 mA
The external power supply has an input voltage range from 90 -264 V/AC 47 - 63 Hz.
PRIMES measurement devices should be driven by PRIMES power supplies only.

9.1.5 PRIMES-Bus - Assignment of the pins
Function		Pin-number		Function		Pin-number
Ground			1 and 6			Trigger RS 485 +4
Data RS 485 +		2			
Trigger RS 485 9
Data RS 485 -		
7			
not assigned		5
DC 24V			3 and 8				

9.1.6 Trigger output - optional
A trigger signal (5V TTL-level) for laser control can be generated by the BeamMonitor50 HQ.
It is also possible to use an external trigger unit.
Thus, it is possible to synchronize the laser pulses to the motion of the measuring rotor.
An integrated delay unit is also available by option.

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9.1.7 Dimensions BeamMonitor50 HQ

Max. screw depth 4.5 mm(additional fastening points
upon request)
Max. screw depth 4.5 mm≙ Measuring position

Max. screw depth 15 mm

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9.2 Laserds.ini - an example
The file laserds.ini, located typically in the folder Program/PRIMES, contains the default
settings for the communication port and the window[Version]
position.
no=7[Window]
left=-4
top=-4right=1156
bottom=840[Comm]
Port=com2
HighBaudrate=1
Rescan=161,144,145,192,112,113[Address]
Own=64[Private]
Mode=0[File]
Default=[Laser]Wavelength=0.01060000
Drehzahlnr=0.00000000
Laserleistung=20000.00000000
Brennweite=127.00000000
StrahlsucheTrigger=210
StrahlsucheProzent=30
Funkvorhanden=0
Detektortyp=0
SperrbereichY0=8.00000000...
...
SperrbereichZ2=30.00000000
Autoscaleon=0[Interface]
Startup=0[Output]
Out0=Port 0...
Out15=Port 15[Input]In0=Port 0...
In15=Port 15[Multimon]
Rescan=32,33,128
Radius=1.
[Service]
Firmenadresse=
Servicetechniker=

If any changes are to be made in the laserds.ini, allprograms of the LaserdiagnosticSoftware must firstbe stopped. Otherwise the new settings can not be
assigned for the next program start-up.
- default setting for the serial-port, which 			is taken from the laserds- default setting for the wavelength		in the calculations

9.3 Interface Devices
9.3.1 PRIMES-Converter
The data communication on the PRIMES-Bus isbased on the RS 485 standard. To connect the bus
to a serial RS 232-Interface of a Personal Computera converter is necessary. Additionally the PRIMESConverter separates the 24 V power-lines of the
PRIMES-Bus from the PC.
The PRIMES-Converter has four LEDs to giveinformation about the current bus-state. They havethe following significance (from left to right):
red
bus power
green
data on bus
red	PC-sent data on the bus
yellow
trigger signal (only for service use)

9.4 PRIMES PLC - interface
PRIMES offers a standard PLC-interface to beaddressed directly via the PRIMES-Bus to integrate
the measurement procedure into the production
process. This means that a measurement can be
external triggered by most of the standard NC
controllers.

[Detectorparameter]

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9.5 Description of the MDF File Format
The MDF file format is a simple ASCII format that contains the most important data of abeam measurement - the spatial power density distribution (PDD). MDF is for ‘mailable
data format’.
With this unified data format, conversion problems between different analysis software canbe reduced so that safer data transmission, for instance by e-mail, is ensured.
The structure of the data is:
1. Line : MDF100 (file identifier)
2. Line : Number of pixels: in x-direction in y-direction
3. Line : Size of the measuring range: dimension in x (mm) dimension in y (mm)4. Line : Position along the axis of beam propagation: z-position (mm)5. Line : Transverse position of the center of the measuring range: x-pos y-pos (mm)6. Line : Amplification of the signal: Amplification (dB)
7. Line : Number of averages: number
8. Line : Offset - value display from the device: Offset - value
In the following lines you find the data: Data
There are at most 80 characters per Line.
Comments:
Lines beginning with a semicolon are treated as comment. Comments can also be addedin the lines after the main data
Example:MDF100;This is an example.
;These lines are comment.
64 64
2 2
11
...
...
1
10
10 10 10 10 10 10 10 10 10 10
11 12 13 14 15 16 17 18 19 20
20 20 20 20 20 18 16 14 12 10

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10. Appendix II - Running LineScan (option)
The LineScan feature allows measurements of the laser beam as a function of time. It
records a single trace of the power density distribution with a repetition rate of slightly
above 30 Hz.
Mechanically, the y-axis of the BeamMonitor50 HQ moves to a steady position and there, itmeasures a single trace of the beam profile with each rotation of the measurement tip. The
data is transferred to the PC via Ethernet. Here, the software offers various analysis tools.
Typically, the user will start by taking a complete 2-dimensional scan of the beam. After thishas been done, the user has to switch into the LineScan mode in the combobox Measuringmode. The software will show the position of the single trace indicated by a blue line. If
necessary, the position of the trace can be modified using a cursor (black triangle to theright of the blue line).
The width of this trace is always the maximum window width of the BeamMonitor50 HQ.
The software automatically selects a new measuring file (e.g. ‘Unnamed 1’) to ensure thatno other data is overwritten.

Fig 10.1: determining the trace position for a LineScan measurement.
Use the cursor (black triangle) to move the blue line.

After a trace position has been selected, you will be prompted for the repetition rate andthe duration of the measurement. A typical setting to observe for example the switch-on
process of a laser could be max. frequency (roughly 33Hz) and 10s time.

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Fig 10.2: menu for repetition rate and measuring time.

The measurement can be stopped any time by pressing the Cancel (Abbrechen) button.
The transfer of the data from the BeamMonitor50 HQ to the PC is indicated by the small
window on the right-hand-side on the bottom of the screen. It can reach the 100% indicator
several times – the LineScan data also is arranged in measurement planes, and each time
one plane is filled, the indicator shows 100%.
Depending on the speed and workload of the PC, it can happen that a small amount of traces
is dropped because the computer is busy while the data is sent from the BeamMonitor50 HQ
to the computer. Typically, this is less than 1% and can be ignored. We recommend using
CPUs with more than 1 GHz and not running other processes in parallel while measuring
at maximum repetition rate.
After a measurement is completed, the data should be saved (menu ‘File/Save As’).
To display and analyze the collected data, the Presentation/Continuous View window isused. While the left side shows a diagram of the variation of the selected beam parameterover time, the right side shows the shape of the trace along the power density at the current
cursor position in time (black triangle). There is a table of different beam parameters
underneath. The scroll-bar in the center can be used to move through large data files.

Fig 10.3: Beam parameters as a function of time visualized with the ‘Presentation/Continuous View’
window.

The diagram on the left side shows a false color representation of the power density of a
trace through the beam as a function of the trace number (or time). Red areas in the centre
mark traces where maximum power density occurred.
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Clearly, the pulse width modulation of the laser can be seen, and traces with high power
density are periodically followed by traces with lower power density (3,5kW laser operated
at 600W).
The cursor can be moved, and the corresponding trace is shown on the top right hand side.
Click on Show Min, Show Max and Show Average to get an idea of the current power
density values compared to the min/max/average values of all traces.
To statistically determine the alterations that happen from trace to trace in one measurement,
the table on the bottom shows not only the min/max/average value, but also the standard
deviations (standard error) for the different parameters.
To display the beam position (centroid), the diameter (86% or 2nd moment) or the area
under the curve as a function of time, just click on the desired value on the table and the
diagram on the left hand side will show the corresponding graph. Click on Auto Scale tochange the scaling of the graph.
To see the false color representation of the power density again, click on ‘False Color’.
The area under the curve can be a rough approximation for the total beam power. This way,a fast power measurement is possible. When analyzing this data, please keep in mind thatthe area under the curve can also be affected when the overall power density distribution
is changed in the 2D beam profile.

	Fig 10.4: A Click on the parameter in the table will display the corresponding graph.

Please note that the 86% values are determined from just one line and may differ noticeably
from the values that are determined from a 2D measurement, as a different algorithm isused (for single trace calculations, 6.7% of the area under the curve are cut off from bothsides, and the remaining length determines the 86% diameter).
The 2nd moment diameters compare much better to the 2D measurements.

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ExampleThe following LineScan measurement shows the switch-on process of a CO2-laser withtraces of organic solvent vapors in the beam path. Blooming occurs.
Within less than a second, the sharp peak broadens and looses its peak intensity.

Fig 10.5: Blooming. Power density distribution right at the start of the laser…

Fig 10.6: …and 0.9 seconds later.

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