35,0(6Original Instructions

MicroSpotMonitor MSM+
MSM+ 35, MSM+ 120
LaserDiagnosticsSoftware LDS

Revision 00 EN – 06/2021

35,0(6MicroSpotMonitor MSM+

IMPORTANT!
READ CAREFULLY BEFORE USE.
KEEP FOR FUTURE USE.

Revision 00 EN – 06/2021

3

35,0(6

MicroSpotMonitor MSM+

Table of contents
1

Basic safety notes82

Symbols and conventions

93

About this operating manual

104Device description

10

4.1
4.2

Functional description..............................................................................................................10
Measuring principle..................................................................................................................12

5

Short overview installation

13

6

Transport and storage

14

7

Selection and change of measuring objectives

16

7.1
7.2
7.3
8

Installation
8.1
8.2
8.3

8.4
9

22

Conditions at the installation site..............................................................................................22
Preparation and mounting position...........................................................................................22
Manually aligning the device.....................................................................................................23
8.3.1 Important conditions for the position of the focused laser beam...................................23
8.3.2 Moving camera housing to axis center position (optional).............................................24
8.3.3 Selecting measuring objective and attaching associated alignment tool.......................25
8.3.4 Aligning device to laser beam.......................................................................................26
Mounting the device.................................................................................................................27

Cooling circuit (500 W device versions only)
9.1
9.2
9.3
9.4

10

Selection of the measuring objective........................................................................................16
Exchanging the measuring objective........................................................................................18
Damage thresholds..................................................................................................................19

28

Water quality............................................................................................................................28
Water pressure.........................................................................................................................28
Humidity...................................................................................................................................29
Water connections and water flow rate.....................................................................................30

Electrical connection31

10.1 Connections.............................................................................................................................31
10.2 Pin assignment........................................................................................................................32
10.2.1 Power supply..............................................................................................................32
10.2.2 Input external trigger....................................................................................................32
10.2.3 Output internal trigger..................................................................................................32
10.2.4 External safety circuit (interlock) ..................................................................................32
10.3 Monitoring of the inspection chamber by external safety circuit (interlock).................................33
10.4 Connection to the PC and power supply..................................................................................35
11

Status display

36

12

Measurement37

12.1 Warning messages...................................................................................................................37
12.2 Switching on the device and connecting it to the LaserDiagnosticsSoftware LDS.....................38
12.2.1 Switching on and connecting device............................................................................38
12.2.2 If the device does not appear in the connections window............................................40
12.2.3 Changing the network address of a connected device.................................................40
12.3 Disconnecting the device from the LaserDiagnosticsSoftware LDS and switching it off.............41

4

Revision 00 EN – 06/2021

MicroSpotMonitor MSM+

35,0(612.4 General procedure for measuring.............................................................................................43
12.4.1 Opening the „Device control“ menu..............................................................................43
12.4.2 Moving camera housing to desired z-position..............................................................43
12.4.3 Opening a measuring mode with adapted toolbench...................................................44
12.4.4 Configuring and saving measurement settings.............................................................45
12.4.5 Performing a measurement..........................................................................................47
12.4.6 Considering messages in the LaserDiagnosticsSoftware LDS during measurement.....48
12.4.7 Checking the quality of the measurement results in the adapted toolbench..................48
12.4.8 Remeasuring a caustic or plane (optional)....................................................................49
12.5 Performing single plane measurement......................................................................................51
12.5.1 Preparatory steps........................................................................................................51
12.5.2 Configuring settings.....................................................................................................52
12.5.3 Configuring advanced settings.....................................................................................55
12.5.4 Measuring a plane.......................................................................................................58
12.5.5 Measuring further planes..............................................................................................60
12.6 Performing continuous plane measurement..............................................................................61
12.6.1 Preparatory steps........................................................................................................61
12.6.2 Configuring settings.....................................................................................................61
12.6.3 Configuring advanced settings.....................................................................................64
12.6.4 Measuring a plane continuously...................................................................................65
12.7 Performing manual caustic measurement.................................................................................67
12.7.1 Preparatory steps........................................................................................................67
12.7.2 Configuring settings.....................................................................................................67
12.7.3 Configuring advanced settings.....................................................................................69
12.7.4 Measuring a caustic manually......................................................................................72
12.8 Performing automatic caustic measurement.............................................................................73
12.8.1 Preparatory steps........................................................................................................73
12.8.2 Configuring settings.....................................................................................................74
12.8.3 Configuring advanced settings.....................................................................................75
12.8.4 Measuring a caustic automatically................................................................................78
12.9 Monitoring beam pointing stability............................................................................................79
12.9.1 Preparatory steps........................................................................................................79
12.9.2 Configuring settings.....................................................................................................79
12.9.3 Configuring advanced settings.....................................................................................80
12.9.4 Measuring beam pointing stability................................................................................81
12.9.5 Logging beam pointing stability....................................................................................83
13

Troubleshooting

84

14

Maintenance and service

85

14.1 Maintenance intervals...............................................................................................................85
14.2 Cleaning...................................................................................................................................85
14.3 Exchanging the protective window...........................................................................................85
14.3.1 Warning messages......................................................................................................85
14.3.2 Replacing the protective window.................................................................................86
14.3.3 Replacing the protective window for cyclone................................................................87
15

Measures for the product disposal

87

16

Declarations of conformity

88

17

Technical data

90

18

Dimensions

91

19

Appendix92

19.1 Insert fixed OD filter (option) in the inspection chamber............................................................92
19.2 Optical components.................................................................................................................93

Revision 00 EN – 06/2021

5

35,0(6

MicroSpotMonitor MSM+

19.2.1 NA limit value, typical magnification and measuring plane distance .............................94
19.2.2 Measuring objective.....................................................................................................95
19.2.3 Prisms.........................................................................................................................97
19.2.4 Fixed filter and filter wheel............................................................................................99
19.2.5 Beam path extension (BPE).......................................................................................100
19.2.6 Field objektive (FO).....................................................................................................100
19.2.7 Absorber....................................................................................................................101
19.2.8 Trigger diode..............................................................................................................101
19.3 Measuring pulsed irradiation...................................................................................................101
19.3.1 Trigger operation........................................................................................................101
19.3.2 Measuring configuration selection..............................................................................102
19.3.3 Influence of the pulse parameters on the integration time control...............................102
19.3.4 Examples for trigger operation...................................................................................106
19.3.5 Summary...................................................................................................................106

6

Revision 00 EN – 06/2021

MicroSpotMonitor MSM+

35,0(6PRIMES - The Company
PRIMES manufactures measuring devices used to analyze laser beams. These devices are employed forthe diagnostics of high-power lasers ranging from CO2 lasers and solid-state lasers to diode lasers. A wavelength range from infrared through to near UV is covered, offering a wide variety of measuring devices todetermine the following beam parameters:••••

Laser power
Beam dimensions and position of an unfocused beam
Beam dimensions and position of a focused beam
Beam quality factor M²

Development, production and calibration of the measuring devices is performed at PRIMES. This guarantees
optimum quality, excellent service, and a short reaction time, providing the basis for us to meet all of ourcustomers’ requirements quickly and reliably.

PRIMES GmbH
Max-Planck-Str. 264319 Pfungstadt
GermanyTel +49 6157 9878-0
info@primes.dewww.primes.de

Revision 00 EN – 06/2021

7

35,0(61

MicroSpotMonitor MSM+

Basic safety notes

Intended use
The device has been designed exclusively for measurements in the beam of high-power lasers.
Use for any other purpose is considered as not intended and is strictly prohibited. Furthermore, intended use
requires that you observe all information, instructions, safety notes and warning messages in this operating
manual. The specifications given in chapter “17 Technical data” on page 90 apply. Any given limit values
must be complied with.
If not used as intended, the device or the system in which the device is installed can be damaged or destroyed. In addition, there is an increased risk to health and life. Only use the device in such a way that there
is no risk of injury.
This operating manual is an integral part of the device and must be kept in the immediate vicinity of the placeof use, accessible to personnel at all times.
Every person who is responsible for the installation, start-up or operation of the device must have read andunderstood the operating manual and, in particular, the safety instructions.
If you still have questions after reading this operating manual, please contact PRIMES or your supplier foryour own safety.
Observing applicable safety regulations
Observe the safety-relevant laws, guidelines, standards and regulations in the current editions published by
the state, standardization organizations, professional associations, etc. In particular, observe the regulations
on laser safety and comply with their requirements.
Necessary safety measures
The device measures direct laser radiation, but does not emit any radiation itself. However, during the measurement the laser beam is directed at the device. This produces scattered or directed reflection of the laser
beam (laser class 4). The reflected beam is usually not visible.
Protect yourself from direct and reflected laser radiation while working with the device by taking the following
measures:
•
•
•
•
•
•
•
•

Never leave the device unattended when taking measurements.
If the device is moved from its aligned position, increased scattered or directed reflection of the laser beamoccurs during measuring operation. Fix the device in such a way that it cannot be moved by unintentional
bumping or pulling on the cables.
Connect the laser control’s safety interlock to the device. Check that the safety interlock will switch off thelaser properly in case of error.
Install safety switches or emergency safety mechanisms that allow the laser to be switched off immediately.
Use suitable beam guidance and beam absorber elements which do not emit any hazardous substances
when irradiated.
Wear safety goggles adapted to the power, power density, laser wavelength and operating mode of thelaser beam source in use.
Wear suitable protective clothing or protective gloves if necessary.
If possible, also protect yourself from direct laser radiation and scattered radiation by using separating
protective devices that block or attenuate the radiation.

Employing qualified personnel
The device may only be operated by qualified personnel. The qualified personnel must have been instructedin the installation and operation of the device and must have a basic understanding of working with highpower lasers, beam guiding systems and focusing units.

8

Revision 00 EN – 06/2021

MicroSpotMonitor MSM+

35,0(6

Conversions and modifications
The device may not be modified in terms of design or safety without the explicit consent of the manufacturer.
The same applies to unauthorised opening, dismantling and repair. The removal of covers is only permitted
within the scope of the intended use.
Liability disclaimer
Manufacturer and distributor exclude any liability for damages and injuries which are direct or indirect consequences of using the device not as intended or modifying the device or the associated software withoutauthorization.

2

Symbols and conventions

Warning messages
The following symbols and signal words indicate possible residual risks in the form of warnings:

DANGER
Means that death or serious physical injuries will occur if necessary safety precautions are nottaken.

WARNING
Means that death or serious physical injuries may occur if necessary safety precautions are nottaken.

CAUTION
Means that minor physical injury may occur if necessary safety precautions are not taken.

NOTICE
Means that property damage may occur if necessary safety precautions are not taken.

Product safety labels
The following symbols are used on the device itself to indicate imperatives and possible dangers:

Hand injuries warning

Electrostatic sensitive devices

Read and observe the operating instructions and safety guidelines before startup!

Revision 00 EN – 06/2021

9

35,0(6

MicroSpotMonitor MSM+

Further symbols and conventions in this operating manual
Here you can find useful information and helpful tips.

Indicates a simple instruction.
If several such instructions appear one below the other, then the order of their execution is irrelevant or they are alternative procedures.

1.
2.
...

A numbered list identifies a sequence of instructions that must be executed in the specified order.

Indicates the result of an action to explain processes that take place in the background.
Indicates an observation prompt to draw attention to visible feedback from the device or the software.
Observation prompts make it easier to check whether an instruction was executed successfully.
Often they also guide to the next instruction.
Points to a control element that is to be pressed / clicked.

Points to an element described in the text (for example an input field).

3

About this operating manualThis manual describes the installation and operation of the device and how to perform measurements with
the LaserDiagnosticsSoftware LDS 1.1.2.
For measurement operation with a PC, the LaserDiagnosticsSoftware LDS must be installed on the PC. The
LDS is included in the scope of delivery.
The software description includes a brief introduction on using the device for measurements.
For a detailed description of the software installation, file management and evaluation of the measurement
data, please refer to the separate instructions for the LaserDiagnosticsSoftware LDS.
This operating manual describes the software version valid at the time of printing. Since the user
software is continuously being developed further, the supplied data medium may have a different
version number.
If you have questions, please let us know the software version you are using. The software version can befound under the following menu item: Help > About LaserDiagnosticsSoftware.

4

Device description

4.1

Functional description

The device determines beam geometry data of focused laser beams with a diameter of 10 µm to 1 mm
directly within the process zone. It is air-cooled and allows measurements in a power range from 1 mW to
200 W. A device version with water cooling for the power range up to 500 W is also available.
The device operates camera-based. The beam cross sections to be measured along the beam propagation
axis are located outside the device. This non-contact measurement has the advantage that even very high10

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

power densities can be measured. The beam cross sections are imaged on a CCD sensor in the device −enlarged by a measuring objective. Before hitting the sensor, the laser beam is attenuated by beam splittersand neutral‑density filters inside the device. From the determined power density distribution of the beamcross-section, beam position and beam radius at this position are obtained.
The camera housing of the device can be moved by a motor on all axes of the device coordinate system.
The travel range along the z‑axis is 35 mm (MSM+ 35) or 120 mm (MSM+ 120). The travel range along thex‑axis / y‑axis is 2 mm. This allows fully automatic plane and caustic measurements.
The device uses interchangeable objectives with the magnification 3.3 / 5 / 10. The selection of the suitablemeasuring objective is essential for the quality of the measurement. The measuring objective should be optimally matched to the wavelength, the numerical aperture and the radius to be measured.
The dynamic range of the integrated CCD sensor is amplified via an irradiation time control. This enables
caustic measurements over more than four Rayleigh lengths, as demanded in the standard ISO 11146.
Optionally, the device can be equipped with a motor-driven filter wheel with neutral‑density filters (OD1 to
OD5). This filter wheel enables measurements of power densities between several W/cm² up to several
MW/cm².
z-axisx-axisCover of the inspection chamber for
filter wheel (optional)
and fixed OD filter (optional)
Handley-axisBeam entrance
Measuring objective with cover

Movable camera
housing

Knurled screw
Absorber withwater cooling

Lever to adjust themagnification

Water connections
Traversing motor

Beam path extension (BPE)Standard

Field objective (FO)Fig. 4.1:

System components (example: MSM+ 120, 500 W device version with water cooling)

Revision 00 EN – 06/2021

11

35,0(64.2

MicroSpotMonitor MSM+

Measuring principle

The device is a camera-based measuring system. Depending on the application, up to 7 different opticalcomponents can be placed within the beam path. The purpose and functionality of individual components
are described in chapter 19.2, „Optical components“, on page 93.
Laser beam
Upper limit
Measuring
plane

Permissible measuring range

Lower limit

Measuringobjective
AbsorberPrismsFixed OD-filter (option)

Mirrors

Field objective (FO)CCD sensor
Absorber

Trigger
Filter wheel (option)
Beam path extension (BPE)

Fig. 4.2:

12

Optomechanical design

Revision 00 EN – 06/2021

MicroSpotMonitor MSM+

535,0(6

Short overview installation

1.

Installing the LaserDiagnosticsSoftware LDS on the PC•

Software is part of the scope of delivery

See separate Operating Manualof the LaserDiagnosticsSoftwareLDS

2.

Taking safety precautions

Chapter 1 on page 8

3.

Transport and storage

Chapter 6 on page 14•

Prepare device for transport / storage

4.

Measuring objective•

Select appropriate measuring objective for the application•

Insert / change measuring objective•

Observe damage thresholds

5.

Installation•

Make preparations•

Set installation position•

Align device manually•

Mount device firmly

6.

Connect the water-cooling (500 W version only)•

Connection diameter•

Observe flow rate

7.

Power supply•

Connect safety interlock•

Connect power supply

8.

Connection with the PC•

Via Ethernet or LAN

9.

Measurement•

Observe warning messages•

Select appropriate measurement mode for the measurement task•

Perform measurement

Revision 00 EN – 06/2021

Chapter 7 on page 16

Chapter 8 on page 22

Chapter 9 on page 28

Chapter 10 on page 31

Chapter 10.4 on page 35

Chapter 12 on page 37

13

35,0(66

MicroSpotMonitor MSM+

Transport and storage

WARNING
Injuries caused by lifting or dropping the device
Lifting and positioning heavy devices can lead, for example, to overstressed intervertebral
discs and chronic changes in the lumbar or cervical spine. The device may fall down.
X If possible, use a lifting device or work in pairs to lift and position the unit.

NOTICE
Damaging / destroying the device
Contamination can damage or destroy the optical components. Components may be damaged if the device is subjected to hard shocks or is allowed to fall.
X Move the camera housing to home position before transporting / storing the device.
X Handle the device with care when transporting it.
X To avoid contamination, close the measuring objective with the supplied cover before transporting / storing the device.
X If possible, transport / store the device in the original PRIMES transport case (optional).

NOTICE
Damaging / destroying the device
X Store the device in a closed room where it is protected from moisture and dirt.
X Only store the device within the permissible environmental conditions specified in chapter“17 Technical data” on page 90.

NOTICE
Damaging / destroying the device
If the unit is water-cooled, it can be damaged by leaking or freezing cooling water.
Even if the pipe system of the cooling circuit has been drained, a small amount of water
always remains in the device. This can leak out and enter the interior of the device.
X Drain the pipe system of the cooling circuit thoroughly before transporting / storing the device. Do not use compressed air for draining.
X Before transporting / storing the device, close the water connections of the cooling circuitwith the sealing plugs provided.
The device only fits into the original PRIMES transport case (optional) when the camera housing is
in home position.

14

Revision 00 EN – 06/2021

MicroSpotMonitor MSM+

35,0(6

To prepare the device for transport / storage:
1. Disconnect the device from the LaserDiagnosticsSoftware LDS and switch it off according to chapter
12.3 on page 41. Make sure that the camera housing is in home position before switching it off.
2. Close the measuring objective with the supplied cover.
3. Disconnect the electrical connections.
4. Only for water-cooled device versions: Drain the cooling circuit thoroughly. Close the water connectionsof the cooling circuit with the supplied sealing plugs.
5. Lift the device by the handle. If you are not using a lifting device, we recommend that two people lift thedevice.
6. If possible, pack the device in the original PRIMES transport case (optional).

Revision 00 EN – 06/2021

15

35,0(6

MicroSpotMonitor MSM+

7

Selection and change of measuring objectives

7.1

Selection of the measuring objective

The selection of the suitable measuring objective is essential for the quality of the measurement. The measuring objective should be optimally matched to the wavelength, the numerical aperture and the radius to bemeasured.
Furthermore, the possible fields of application are limited by the sensor- and pixel size (see chapter 19.2.2,„Measuring objective“, on page 95).

10x
+ BPE
10x+SWV

10x10x5x+SWV
5x
+ BPE

5x 5x

3,3x+SWV
3.3x
+ BPE

3.3x
3,3x
1
1

10
10

100
100

1000
1000

Spotdurchmesser in µm

Beam diameter in μm
Fig. 7.1:

Fields of application of the measuring objectives

Fig. 7.1 shows the field of application of different measuring objectives. The diagramm enables a quick first
selection of the suitable measuring objective.

16

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

The following table specifies the limits that apply to standard objectives. On the basis of this table, a suitablemeasuring objective can be selected. The values apply for a wavelength of 1 064 nm (the values are slightly
different for other wavelengths).
Standard
Objective

NA

F

Max. measuring window

Min. resolution

Min. beam diameterMax. beam diameter

3.3x

0.11

5

1.4 mm

1.4 μm

30 μm

1 mm

5x

0.19

910 μm

0.9 μm20 μm

650 μm10x

0.24

510 μm

0.5 μm11 μm

350 μm2

With beam path extension (BPE)
Objective

NA

F

Max. measuring window

Min. resolution

Min. beam diameterMax. beam diameter

3.3x

0.11

5

800 μm

0.8 μm17.5 μm

550 μm5x

0.19

550 μm

0.5 μm12 μm

380 μm10x0.24

320 μm

0.3 μm7 μm

220 μm2

With field objective (FO)
Objective

NA

F

Max. measuring window

Min. resolution

Min. beam diameterMax. beam diameter

3.3x

0.11

5

4 mm

3.9 µm90 µm

2.8 mm5x0.192.75 mm

2.7 µm

60 µm

2 mm

10x

0.24

1.6 mm

1.6 µm35 µm

1.1 mmTab. 7.1:

Measuring objective data

2

NA = numerical aperture
F = focusing value (see Formula 7.2 on page 20)

Revision 00 EN – 06/2021

17

35,0(67.2

MicroSpotMonitor MSM+

Exchanging the measuring objective

1. Unscrew the two knurled screws.
2. Remove the measuring objective upwards. Note that the measuring objective is fixed by two dowel pins
and will not tilt during removal.

Knurled screw

Dowel pins 2x
Fig. 7.2:

Measuring objective inserted

NOTICE
Component susceptible to electrostatic discharge
The EEPROM can be destroyed by an electrostatic discharge.
X Do not touch the contacts of the EEPROM as well as the contact pin.
X Put on an ESD armband before changing the measuring objective.
There is an EEPROM in the mount of the measuring objectives, which contains all the objective data necessary.

Contact pins

Dowel pins 2x

Fig. 7.3:

Measuring objective removed

3. Place the measuring objective from above on the two dowel pins.
4. Press the measuring objective down vertically as far as it will go. When inserting, make sure that it does
not tilt.

18

Revision 00 EN – 06/2021

MicroSpotMonitor MSM+

7.3

35,0(6

Damage thresholds

The operating limits of the device are determined by the damage thresholds of the optical components.

NOTICE
Damaging / destroying the measuring objective
Measuring objectives can be destroyed by an excessive power / energy density.
X Observe the following maximum values on the first lens:• Max. power density with CW: 10 MW/cm²• Max. energy density at pulse length > 10 ns: 3 J/cm²
X The maximum average power for the wavelength range 1030 nm to 1090 nm (NIR) is 200 W(500 W for water-cooled device versions). The permissible power decreases for shorter
wavelengths.
The power density I is calculated according to the following formula:

Formula 7.1:••

Formula for calculating the power density I

If the beam focus is placed below the measurement range (too close to the measuring objective), the power
density rises at the first lens of the measuring objective.
If the focus is above the measuring plane, an intermediate focus develops inside the device. If the laser
beam focus is too far above the measurement range, the intermediate focus can develop in areas in which
the beam power has not been sufficiently decreased. This can damage the image-sided beam path.

The size and position of the area in which the beam focus is to be positioned before the first measurement
depends on the choice of the measuring objective, the used wavelength as well as on the beam path.
The diagram in Fig. 7.4 on page 20 shows that the upper limits for high-magnification measuring objectives are much narrower than those with a 3.3-fold magnification.
The lower limit for convergent beams depends on the power density of the laser beam on the first lens. Thisis a function of laser power, amount of focusing, M², as well as raw beam diameter.

Revision 00 EN – 06/2021

19

35,0(6

MicroSpotMonitor MSM+

The graphs in Fig. 7.4 and Fig. 7.5 can be used to estimate the minimum distance.
Measuring plane distance
PRIMES 10x without BPE
Measuring plane distance
PRIMES 3,3x without BPE
5
F=5Beam radius on the first lens in mm

4.5
4

F = 10

3.5
3
F = 15

2.5

F = 202
1.5

F = 301
0.5
0Fig. 7.4:

20

30
40
50
60
70
Distance between focus and measuring objective in mm

80

Estimatation by the focusing value F for 1 064 nm and 532 nm

The diagram in Fig. 7.4 shows the dependence of the beam radius on the first lens with the focusing value F
and the distance of the focal plane to the first lens of the measuring objective.
The focusing value F can be determined by means of the following formula:

Formula 7.2:

Formula for calculating the focusing value F

f = Focal length of the focusing lensds = Raw beam diameterΘ = Full divergence angle

20

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

Measuring plane distance
PRIMES 10x without BPE
Measuring plane distance
PRIMES 3,3x without BPE

Beam radius on the first lens in mm

532 nm1064 nm

2.5

5

2

4

w0 = 5 μm
M² = 1
w0 = 8 μm

1.5

3

1

2

0.5

1

0

0

Fig. 7.5:

w0 = 10 μm
w0 = 15 μm
w0 = 30 μm
w0 = 50 μm
20

30

40
50
60
70
Distance between focus and measuring objective in mm

80

Estimatation by the focus radius for 1 064 nm and 532 nm

The diagram in Fig. 7.5 shows the dependence of the beam radius on the first lens with the wavelength, thefocus radius, and the distance of the focal plane to the lens.
The beam radii are estimated by means of the beam parameter product BPP.

Formula 7.3:

Formula for calculating the beam radii by the beam parameter product BPP

w0 = Beam radius
Θ = Full divergence angle
λ = Wavelength
M2 = Beam quality factor

In Fig. 7.5 the beam quality factor M² was assumed to be 1.
The dependencies can be summarized as follows:•••

When it comes to strongly divergent beams, for example with a focusing with small focal lengths, small
focus radii develop. In order to be able to achieve a sufficient resolution on the camera chip, the 10-foldmeasuring objective is necessary. This objective also has a greater numerical aperture.
When it comes to laser beams with a beam quality factor M² = 1-2, small focus radii also occur with small
divergences. This may lead to damages of the entry lens when long focal length objectives are used.
When it comes to laser beams with large beam quality factor M² values, high power values occur. They
are, however, not so critical due to the large focus radii. The spot diameter on the entry lens should always
be greater than 1 mm.

Revision 00 EN – 06/2021

21

35,0(68

MicroSpotMonitor MSM+

Installation

CAUTION
Crushing hazard
The camera housing of the device can be moved along the z-axis.
X Never reach into the traversing range of the camera housing.
Possible hazard spots are marked on the device as follows:

NOTICE
Damaging / destroying the device
Contamination can damage or destroy the optical components. Components may be damaged if the device is subjected to hard shocks or is allowed to fall.
X Handle the device carefully when installing it.

8.1
•
•
•
•

8.2

Conditions at the installation site
The device must not be operated in a condensing atmosphere.
The ambient air must be free of organic gases.
Protect the device from splashes of water and dust.
Operate the device in closed rooms only.

Preparation and mounting position

NOTICE
Damaging / destroying the device
The camera housing of the device can be moved along the z-axis. Obstacles in the traversing range of the device can lead to collisions and damage the device.
X Always keep the traversing range of the camera housing free of obstacles.
The device is intended for operation in horizontal position with beam incidence from above. An optional sideplate enables operation with horizontal beam incidence (order number 801-004-060). The device must be
set up stably and fastened with screws (see chapter 8.4 on page 27)).
XX Check the space available before mounting the device. Special attention must be paid to the required
space for the connecting cables and the traversing range of the z‑axis (see chapterchapter 18, „Dimensions“, on page 91).

22

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

8.3

Manually aligning the device

8.3.1

Important conditions for the position of the focused laser beam

The device must be aligned to the laser beam both along the z‑axis and on the x‑y plane. Fig. 8.1 shows
schematically the essential conditions for the manual alignment.
z-axisLaser beam

Upper limit
Measuring plane

Permissible
measurement range

Lower limit
y-axisMeasuring plane distance
Measuring objective

x-axisBeam hits measuring objective
centrally and perpendicularly
Fig. 8.1:

Alignment along the device axes

Position of the measuring objective on the z-axis (measuring plane distance)
The measuring objective is designed to image a measuring plane onto the CCD sensor. The measuring
plane is placed outside the measuring device. The beam must be aligned along the z-axis into the measuring
plane.
Ideally, the beam focus is placed exactly on the measuring plane after alignment. In practical use, it is sufficient if the beam focus is placed within the limits of a permissible measurement range. Otherwise, themeasuring objective can be damaged if beam intensities are too high.
The upper and lower limits of the permissible measurement range depend on the specific application. Selection of measurement objective, wavelength used and type of focusing of the laser are particularly important.
Before aligning, the specific measuring plane distance must be determined from Tab. 8.1. This is the distance between the measuring objective and the measuring plane. Tab. 8.1 shows that the measuring plane
distance depends on the following factors:• Magnification of the measuring objective• Wavelength of the laser• Use of additional optical components inside the device (beam path extension BPE or field objective FO)
The values listed in the table correspond to the distance between the measuring plane and the upper edgeof the measuring objective.

Revision 00 EN – 06/2021

23

35,0(6
Measuringobjective

3.3x

5x

10x

MicroSpotMonitor MSM+

Measuring plane distance in mm
Standard

using
beam path extension (BPE)usingfield objective (FO)

1 064 nm
532 nm355 nm

73
70.5
67.3

64.6
62.6
60.1

63.7
61.5
57.7

1 064 nm
532 nm355 nm

51.1
49.3
47.2

47.1
45.7
43.8

46.7
45.1
42.7

1 064 nm
532 nm355 nm

29.9
—
—

27.9
—
—

27.6
—
—

Tab. 8.1:

Measuring plane distances in mm

If a 1.5 mm thick protective window is used, the measuring plane distance increases by approx.
500 µm.
Due to manufacturing tolerances, the values of the measuring plane distance listed in Tab. 8.1 aresubject to an error of ± 800 µm. However, it is possible to validate the measuring plane distance ofthe measuring objectives to an accuracy of ± 50 µm (TCP determination).
For detailed information on the damage thresholds of the optical components, refer to chapter 7.3, „Damage
thresholds“, on page 19. In this chapter you will find diagrams for determining the limits of the permissible
measurement range.
Position of the measuring objective on the x-y plane
Fig. 8.1 also shows the alignment of the device on the x-y plane: the laser beam must hit the measuring
objective centrally and perpendicularly so that it is imaged centrally on the CCD sensor.
8.3.2

Moving camera housing to axis center position (optional)

XX Before aligning and mounting the device, check the approximate z-position of the camera housing.
If the camera housing is in home position, it cannot be moved further down on the z‑axis during measurement. We recommend moving the camera housing to the center position of the z‑axis before alignment. If acaustic measurement is to be performed, the same amount of travel is available on both sides of the expected beam focus.

CAUTION
Crushing hazard
The camera housing of the device can be moved along the z-axis.
X Never reach into the traversing range of the camera housing.

NOTICE
Damaging / destroying the device
The camera housing of the device can be moved along the z-axis. Obstacles in the traversing range of the device can lead to collisions and damage the device.
X Always keep the traversing range of the camera housing free of obstacles.

24

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

Proceed as follows to move the camera housing to the axis center position:
1. Establish the electrical connections according to chapter 10 on page 31.
2. Switch on the device and connect it to the LaserDiagnosticsSoftware LDS according to chapter 12.2 on
page 38.
3. Open the Device control menu according to chapter 12.4.1 on page 43.
4. Move the camera housing to the axis center position according to chapter 12.4.2 on page 43.
8.3.3

Selecting measuring objective and attaching associated alignment tool

To simplify the alignment of the device to the laser, suitable alignment tools are supplied.
Marking in the alignment tool

10x

Fig. 8.2:

5x

3.3x

Alignment tools for direct placement on the measuring objective

Marking in the alignment tool

10x

5x

3.3x
Protective window mountFig. 8.3:

Alignment tools for placement on the protective window mount

Revision 00 EN – 06/2021

25

35,0(6

MicroSpotMonitor MSM+

Special alignment tools are supplied for measuring objectives with a cyclone.
Marking in the alignment tool

Protective
window
Cyclone with disassembled protective window
mount and attached alignment toolFig. 8.4:

Alignment tool

Cyclone with mounted protective window
mount and removed alignment tool

Alignment tool for an optional cyclone (example: 3.3x measuring objective)

1. Depending on your specific application, select the appropriate measuring objective according to chapter
7 on page 16.
2. Insert the measuring objective into the device according to chapter 7.2 on page 18.
3. Place the appropriate alignment tool directly on the measuring objective (see Fig. 8.2), on the protective
window mount (see Fig. 8.3) or on the cyclone (see Fig. 8.4).
8.3.4

Aligning device to laser beam

Proceed as follows to align the device with the alignment tool:
1. Switch on the pilot laser.
2. Align the device on the x-y plane in such a way that the laser beam hits the mark in the alignment tool
perpendicularly.

NOTICE
Damaging / destroying the device
Excessive power densities can damage the measuring objective. The distance between the
focal plane and the measuring objective must remain within the previously defined measurement range.
X Align the device along the z-axis in a way ensuring that the beam focus is placed within theupper and lower limits of the permissible measurement range.
3. Align the device along the z-axis in a way ensuring that the beam focus is placed within the upper andlower limits of the permissible measurement range (see Tab. 8.1 on page 24). The device is roughlyaligned along the z‑axis when the beam focus is on the mark of the alignment tool.

26

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

8.4

Mounting the device

DANGER
Serious eye or skin injury due to laser radiation
If the device is moved out of the aligned position, there will be increased scattered or directed reflection of the laser beam (laser class 4).
X Mount the device in such a way that it cannot be moved by unintentional bumping or pullingon the cables.
166.6
157.5

150
187.5
2x Ø112x Ø6.6

160
194.8
54.8 ±0.5
21

160
21

202

4x Ø 6.6 Ø11

157.5

187.5
316.6 +12

Fig. 8.5:

Fastening bores, view from above (all dimensions in mm)

For the installation onto a holder provided by the customer, there are four mounting holes Ø 6,6 mm in thebottom plate. We recommend screws M6 (strength class 8.8; tightening torque 20 Nm). The total length of
the screws depends on the dimensions of the customer's bracket.
XX Fasten the housing with at least 4 M6 screws.

Revision 00 EN – 06/2021

27

35,0(69MicroSpotMonitor MSM+

Cooling circuit (500 W device versions only)

DANGER
Fire hazard; Damage / Destruction of the device due to overheating
If there is no water cooling or an insufficient water flow rate, there is a danger of overheating,which can damage the device or set it on fire.
X Operate the device with a connected water cooling only and a sufficient water flow rate.
Note that the flow rate is not monitored by the external safety circuit (interlock).

9.1

Water quality

NOTICE
Damage / Destruction of the device due to different chemical potentials
The parts of the device which get in contact with cooling water consist of copper, brass or
stainless steel. Connecting the unit to a colling curcuit containing aluminum components
may cause corrosion of the aluminum due to the different chemical potentials.
X Do not connect the device to a cooling circuit in which aluminum components are installed.
•
•
•
•

9.2

The device can be operated with tap water as well as demineralized water.
Do not operate the device on a cooling circuit in which aluminum components are installed. Especially whenit comes to the operation with high powers and power densities, it may otherwise lead to corrosion in thecooling circuit. In the long term, this reduces the efficiency of the cooling circuit.
Should the cooling fail, the device can withstand the laser radiation for a few seconds. In this case, pleasecheck the device as well as the water connections for damages.
Large dirt particles or teflon tape may block internal cooling circuits. Therefore, please thoroughly rinse thesystem before connecting it.

Water pressure

Typically, 2 bar primary pressure at the inlet of the absorber with depressurized drain is sufficient to ensure
the necessary flow rate.

NOTICE
Damage / Destruction of the device due to overpressure
X The maximum permissible water inlet pressure is 4 bar.

28

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

9.3
•
•

Humidity
The device must not be operated in a condensing atmosphere. The humidity has to be considered in orderto prevent condensates inside and outside the device.
The temperature of the cooling water must not be lower than the dew point (see Tab. 9.1).

NOTICE
Damage / Destruction of the device due to condensing water
Condensation water inside of the device can lead to damage.
X Mind the dew-point in Tab. 9.1.

40

100

35

80
70
60

30

50
25

40

20

30

15

20

10

Relative humidity in %Cooling water temperature in °C

Only cool the device during the measuring operation. We recommend starting the cooling approx. 2 minutes
before the measurement and terminating it approx. 1 minute after the measurement.

5
10

0
0

Tab. 9.1:

5

10

15
20
25
30
Air temperature in °C

35

40

Dew point diagram: The temperature of the cooling water must not be lower than the dew point

ExampleAir temperature:		Relative humidity:

22 °C
60 %

The cooling water temperature must not fall below 14 °C.

Revision 00 EN – 06/2021

29

35,0(69.4

MicroSpotMonitor MSM+

Water connections and water flow rate

Connection diameter

Recommended flow rate

Minimum flow rate

PE hoses 6 mm

1.5 l/minnot lower than 1.0 l/min

Tab. 9.2:

Water connections and water flow rate

Removing the sealing plugs of the water connections
1. With two fingers of one hand, push down the releasering of the connection and pull out the plug with yourfree hand.

Release ring

2. Remove both sealing plugs of the water connections
and keep it in a save place.

1. Push

2. PullFig. 9.1:

30

3. Close the flow line (Water In) and the return flow (Water
Out) of the device, by inserting the hose as far as possible (approx. 20 mm deep).

Removing the sealing plugs of the water connections

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

10Electrical connection

The device requires a supply voltage of 24 V ±5 % (DC) for operation. Power supply and connecting cables
are provided.
Observe the correct sequence:
All electrical connections must be established before the device is switched on (see chapter 12.2
on page 38).
Only the provided PRIMES power supply and connecting cables are to be used.

10.1

Connections
On/Off switch

Power supply

Fig. 10.1:

LAN socket

Input
external trigger
BNC

Outputinternal trigger
BNC

External safety circuit(interlock)Connections

Revision 00 EN – 06/2021

31

35,0(6

MicroSpotMonitor MSM+

10.2

Pin assignment

10.2.1

Power supply

Harting M12-P-PCB-THR-2PC-5P-LCOD-M-STR (view: connector side)
3

2

4

1
FE

Tab. 10.1:

10.2.2Pin

Function

1

+24 V

2

Not assigned

3

GND

4

Not assigned

5

FE (functional earth)

Connection socket for the PRIMES power supply in the connection panel

Input external trigger

BNC connector (view: connector side)

1
2

Fig. 10.2:

10.2.3Pin

Function

1+5 V (Trigger signal)

2

GND

Connection socket Inlet for an external trigger in the connection panel

Output internal trigger

BNC connector (view: connector side)

1
2

Fig. 10.3:

10.2.4Pin

Function

1+5 V (Trigger signal)

2

GND

Connection socket Outlet for the internal trigger in the connection panel

External safety circuit (interlock)See chapter 10.3, „Monitoring of the inspection chamber by external safety circuit (interlock)“, on page 33.

32

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

10.3

Monitoring of the inspection chamber by external safety circuit (interlock)The device has a connection for an external safety circuit (interlock), which monitors the cover of the inspection chamber during operation. If the cover is opened, the laser switches off.
The M8 device connector provides connections for two redundant safety circuits. A matching 8-pin cable
socket is included in the scope of delivery.

DANGER
Serious eye or skin injury due to laser radiation
If the inspection chamber is open, reflected radiation (laser class 4) can escape from thedevice during measurement operation.
If the external safety circuit is not connected, the cover of the inspection chamber is notmonitored.
X Only operate the device with the cover closed and the safety circuit correctly connected.
X Check that the safety interlock will switch off the laser properly in case of error.

Cover

Inspection chamber

Fig. 10.4:

Inspection chamber opened
External safety circuit(interlock)Fig. 10.5:

Device connector of the external safety circuit

Revision 00 EN – 06/2021

33

35,0(6

MicroSpotMonitor MSM+

XX Connect the external safety circuit according to Tab. 10.2. If pin 1 and pin 3 (and pin 4 and pin 6) areconnected, the laser is switched off.
Pin 7 must be connected to pin 8 via an external switch or bridge so that the circuit to the interlock
relay is closed.
If the socket is not plugged in, the safety circuit is not active. In this case, a warning message isdisplayed in the LaserDiagnosticsSoftware LDS.
M8 connector 8-pin (view connector side)

2

1
8

3
4

7
6

5

Pin

Function1

Connected with pin 2 when ready for operation. Connected with pin 3
when not ready.

2

Connected with pin 1 when ready for operation.

3

Connected with pin 1 when not ready for operation.

4

Connected with pin 5 when ready for operation. Connected with pin 6
when not ready.

5

Connected with pin 4 when ready for operation.

6

Connected with pin 4 when not ready for operation.

7

Connection for switch or bridge

8+ 24 V (applied), connection for switch or bridge

Matching ready-made cable: Binder 79-3808-52-08
Tab. 10.2:

34

Pin assignment of the safety interlock connector

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

10.4

Connection to the PC and power supply

NOTICE
Damage / destruction of the device due to voltage peaks
Disconnecting the connecting cables during operation causes voltage peaks. This could
destroy the communication modules of the device.
X Connect / disconnect all plugs only when the power is off.
1. Connect the device with the PC via a crossover cable or with the network via a patch cable.
2. Plug the power supply into the connector socket for the power supply.
PRIMES Power SupplyorCrossover Cable

Fig. 10.6:

Patch cable

Ethernet

Ethernet

PC

LAN

Connection via Ethernet with a PC or a local network

Revision 00 EN – 06/2021

35

35,0(611

MicroSpotMonitor MSM+

Status display

The status display consists of an indicator field. The various device states are indicated by different lights.
Color

Meaning

White

The device is switched on and operational

Yellow

A measurement is running.

Red

Lights up briefly: a measuring plane is being recorded.
Staying lit: a device error has occurred. The device error is shown in the LaserDiagnosticsSoftware
LDS.

Tab. 11.1:

Different lighting of the status display

Status display

Tab. 11.2:

36

Status display

Revision 00 EN – 06/2021

MicroSpotMonitor MSM+

1235,0(6

Measurement

This chapter describes measurements with the LaserDiagnosticsSoftware LDS. For a detailed description of
the software installation, file management and evaluation of the measured data, refer to the separate operating manual LaserDiagnosticsSoftware LDS.

12.1

Warning messages

DANGER
Serious eye or skin injury due to laser radiation
The device measures direct laser radiation, but does not emit any radiation itself. However,during the measurement the laser beam is directed at the device. This produces scatteredor directed reflection of the laser beam (laser class 4). The reflected beam is usually not
visible.
X Connect the laser control’s safety interlock to the device. Check that the safety interlock
will switch off the laser properly in case of error.
X Wear safety goggles adapted to the power, power density, laser wave length and operating
mode of the laser beam source in use.
X Wear suitable protective clothing or protective gloves if necessary.

CAUTION
Crushing hazard
The camera housing of the device can be moved along the z-axis.
X Never reach into the traversing range of the camera housing.

NOTICE
Damaging / destroying the device
Contamination and fingerprints on the protective window can lead to damage or shatteringor splintering of the protective window.
X Do not touch the protective window.
X Regularly check the condition of the protective window and exchange it in case of pollution(see chapter 14.3, „Exchanging the protective window“, on page 85).
X Only operate the device with a clean protective window.

NOTICE
Damaging / destroying the device
The camera housing of the device can be moved along the z-axis. Obstacles in the traversing range of the device can lead to collisions and damage the device.
X Always keep the traversing range of the camera housing free of obstacles.

Revision 00 EN – 06/2021

37

35,0(6

MicroSpotMonitor MSM+

12.2

Switching on the device and connecting it to the LaserDiagnosticsSoftware LDS.

12.2.1

Switching on and connecting device

CAUTION
Crushing hazard
The camera housing of the device can be moved along the z-axis.
X Never reach into the traversing range of the camera housing.

NOTICE
Damaging / destroying the device
The camera housing of the device can be moved along the z-axis. Obstacles in the traversing range of the device can lead to collisions and damage the device.
X Always keep the traversing range of the camera housing free of obstacles.
If the camera housing was not in the home position when the device was switched off / disconnected from power source, then it moves to the home position after it is switched on / connected to
power source. This happens even before the device is connected to the LaserDiagnosticsSoftware
LDS. The axes are referenced to the home position.
Observe the correct sequence:• All electrical connections must be established before the device is switched on (see Kapitel “10Electrical connection” on page 31).
• The device must be switched on before the LaserDiagnosticsSoftware LDS is started.
1.

Switch on the device.

On/Off switch

Status display

The operating status is shown in thestatus display. If the device is readyfor operation, the display lights up
white.
If necessary, the camera housing
moves to the home position.

2.

Use one the following options to startthe LaserDiagnosticsSoftware LDS:XX Double-click left on the program iconin the start menu group.
XX Double-click left on the desktop
shortcut.
The start logo appears for a short
time.

38

Revision 00 EN – 06/2021

MicroSpotMonitor MSM+

35,0(6

Only if the Show start screen option isenabled:The start screen appears.
3.

Select the Measure operating mode.

Only if the Show start screen option isdisabled:
4.

Click on the Devices tab and then on
the +Connect to device button.

The Connections window appears.
If the device appears in the Connections window:
5.

Click on the desired device.

6.

Click on the Connect to device button.

If the device does not appear in theConnections window:
7.

Follow the instructions in chapter
12.2.2 on page 40.

Revision 00 EN – 06/2021

39

35,0(612.2.2

MicroSpotMonitor MSM+

If the device does not appear in the connections window

The connection of the device to the LaserDiagnosticsSoftware LDS may be blocked
by the firewall:

The UDP port should be enabled by a system administrator.

XX In Windows > Control panel > Firewall, enable the UDP port 20034
The network address of the PC is notwithin the range of the device.

The IP address should be entered by a system administrator.

XX In Windows > Control panel > Network and Sharing Center, assign an
IP address to your PC that is in thesame address range as the device.
The IP address of your device can befound on the identification plate.
If several network interface cards or aUSB3-to-Ethernet card are installed in
the PC, the connection of the device tothe LaserDiagnosticsSoftware LDS may
be blocked by the selection of the wrong
network interface card.
1.

Select the appropriate network interface card in the Connections > Allwindow.
The device is displayed in the Connections window.

2.

Click on the device.

3.

Click on the Connect to device button.

12.2.3

Changing the network address of a connected device

Proceed as follows in order to assign a different IP address to a connected device:
1.
2.
3.
4.

40

Click on the Devices tab.
Right-click on the device and selectthe Device settings menu point.
Enter in the desired IP address or
use the Use DHCP option and confirm the entry with OK.
Switch the device off and on again.

Revision 00 EN – 06/2021

MicroSpotMonitor MSM+

12.3

35,0(6

Disconnecting the device from the LaserDiagnosticsSoftware LDS and switching it
off

When measurements are completed, the device must be disconnected from the LaserDiagnosticsSoftware
LDS and switched off.

CAUTION
Crushing hazard
The camera housing of the device can be moved along the z-axis.
X Never reach into the traversing range of the camera housing.

NOTICE
Damaging / destroying the device
The camera housing of the device can be moved along the z-axis. Obstacles in the traversing range of the device can lead to collisions and damage the device.
X Always keep the traversing range of the camera housing free of obstacles.
Observe the correct sequence:• The device must be disconnected from the LaserDiagnosticsSoftware LDS before it is switched off.
• The device must be switched off before the connecting cables are disconnected.
If the camera body was not in the home position when the device was switched off, it will moveback to home position when it is switched on again (see chapter 12.2 on page 38).
The camera housing must be in the home position before the device is transported or stored.

Revision 00 EN – 06/2021

41

35,0(61.

Click on the Devices tab.

2.

Right-click on the device and selectthe Disconnect menu point.

MicroSpotMonitor MSM+

The Close connection window appears.
3.

Select one of the options offered:

XX Confirm by clicking the OK button.
Select this option to prepare thedevice for transport or storage.
The device is disconnected from theLaserDiagnosticsSoftware LDS. The
camera housing moves to home position.
XX Click on the Cancel button.
The device is disconnected from theLaserDiagnosticsSoftware LDS. The
camera housing remains in the current axis position.
4.

Switch off the device.
The status display turns off.

5.

Disconnect the electrical connections
if necessary.

42

On/Off switch

Status display

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

12.4

General procedure for measuring

This chapter describes in general which steps are necessary after connecting your device with theLaserDiagnosticsSoftware LDS to perform measurements and what you should pay attention to. Read thisgeneral information before you turn to the following chapters on the different measuring tasks.
12.4.1

Opening the „Device control“ menu

Immediately after connecting the device, the Device control menu must be opened:1.

Click on the Devices tab.

2.

Select the device and click on the device function CCD below the device
name.
The Device control menu with the
Adjustment and Measuring modes
sections opens.

Device function

12.4.2Moving camera housing to desired z-position

The Adjustment area of the Device control menu offers various options for moving the camera housing.
OptionExplanation

z-Position in mm

XX Enter the desired z-position in the input field or use the slider.

Move to axis position

XX Click this button to move the camera housing to the z position
specified in the z-Position in mm field.

Move to axis center position

XX Click this button to move the camera housing to the center positionof the (unlocked) z-axis traversing range.
Note that this does not have to be the maximum traversing range ofyour device. If a locked area of the z-axis was stored in the EEPROM
during a previous use of the device, then this locked area is active. The
camera housing then moves to the center position of the unlocked
range.

Tab. 12.1:

Options in the Adjustment area of the Device control menu

Revision 00 EN – 06/2021

43

35,0(612.4.3

MicroSpotMonitor MSM+

Opening a measuring mode with adapted toolbench

In the Device control menu, a measuring mode can be selected. Here, all relevant settings for a measuring task are clearly arranged in a menu. For example, to measure individual planes, the Single planes mode
provides all the options necessary.
The following measuring modes can be selected:• Single planes (see chapter 12.5, „Performing single plane measurement“, on page 51)• Monitor (see chapter 12.6, „Performing continuous plane measurement“, on page 61)• Manual caustic (see chapter , „“, on page 66)• Automatic caustic (see chapter 12.8, „Performing automatic caustic measurement“, on page 73)• Beam pointing (see chapter 12.9, „Monitoring beam pointing stability“, on page 79)
We recommend opening the adapted toolbench immediately after selecting a measuring mode. The toolbench is displayed in the main area of the user interface and contains the most important tools for displaying
and evaluating measurement results.
Opening a measuring mode and theadapted toolbench
1.

Open the Device control menu according to chapter 12.4.1 on page
43 .

2.

After opening the Device control
menu, click the button of the desired measuring mode, for example
Single planes.

A drop-down list for changing themeasuring mode appears in the upper area of the Device control menu.
Optional:
3. Click on the arrow to open the dropdown list.
4. Click on the measuring mode towhich you want to switch.

44

Revision 00 EN – 06/2021

MicroSpotMonitor MSM+

35,0(6

Only if the Open measurement toolbenches option is enabled in the
Extras > Options menu:
The toolbench adapted to the selected measuring mode is automatically opened in the main area of theuser interface.

Only if the Open measurement toolbenches option is disabled in the
Extras > Options menu:
The Open measurement toolbenchbutton appears in the upper area of
the Device control menu.
This button also appears for the selected
measuring mode whenever the customized toolbench had been closed.
5.

Click this button to open the adapted
toolbench in the main area of the userinterface.

12.4.4

Configuring and saving measurement settings

After selecting a measuring mode, numerous measurement and device settings in the Settings and Advanced tabs of the Device control menu can be configured. Which options exactly and what you need toknow about them is described in the following chapters on the different measuring tasks. However, some
operating steps in the Device control menu apply equally to all measuring modes. They are described in thefollowing overview.
When configuring settings in one mode, note that some options may also be offered in other modes. For example, if a parameter is entered in the Single planes mode, it will automatically be applied to all other modes
that have that same parameter field.
When saving / loading a configuration, note that although the command is made in a specific measuringmode, the saved / loaded data set also includes the settings of the other measuring modes.

Revision 00 EN – 06/2021

45

35,0(6

MicroSpotMonitor MSM+Entering and activating parameters
To transfer a parameter value entered in
the Device control menu to the active
configuration, it must be confirmed with
the Enter key.
1.

2.

Enter the desired value in the parameter field.
The background color of the parameter field changes to blue.
Confirm the entry by pressing theEnter key.
The field returns to its original background color.

Saving a configuration in the device
All options marked with an asterisk in the
Device control menu can be saved in the
EEPROM in the device.
In this case, the settings are retained even
if the device is switched off or disconnected from the power source.
1.

Click on the Advanced tab.

2.

Click on the Save device settings
button.

Saving a safety-relevant locked area
We recommend saving a configuration in
the device especially if a safety-relevant
locked area is configured in the Advanced tab.

If the locked area was configured
but not saved via Save device settings, then a dialog box appears after
clicking the Start button (to start ameasurement).
XX If you now want to save the locked
area (and the other options marked
with an asterisk) in the device, click
the OK button.
XX Otherwise, click on the Cancel button.
xx The settings are active during themeasurement, but must be configured again when the device isswitched off or disconnected from thepower source.

46

Revision 00 EN – 06/2021

MicroSpotMonitor MSM+

35,0(6

Saving a configuration to a file / loading from a file
All options marked with an asterisk in the
Device control menu can be saved to apreset file with the .pre extension.
XX To save a configuration,
click theicon.
XX To load a configuration,
click theicon.

12.4.5

Performing a measurement

Once the measurement and device settings have been configured, a measurement can be performed. The
corresponding procedures are described in the following chapters for the different measuring tasks.

Revision 00 EN – 06/2021

47

35,0(612.4.6MicroSpotMonitor MSM+

Considering messages in the LaserDiagnosticsSoftware LDS during measurement

If problems occur during a measurement, the LaserDiagnosticsSoftware LDS displays them in different categories and different colors.
Notes
Notes provide assistance in interpretingthe measurement results and are displayed in a blue window.
Use one of the following options:
XX Click on the warning triangle in thefooter to display / hide the window.
XX If applicable, click the Next message
button to display more messages ofthe same category.
XX Click the Confirm button to remove
the displayed message.
Warnings
Non-safety-critical problems that influence
the quality of the measurement results,
for example, are displayed in a yellow
window.
Use one of the following options:
XX Click on the warning triangle in thefooter to display / hide the window.
XX If applicable, click the Next message
button to display more messages ofthe same category.
XX Click the Confirm button to remove
the displayed message.
Safety critical device errors
Safety-critical problems that can result indamage / destruction of the device aredisplayed in a red window.
In this case, proceed as follows:
1. Fix the problem immediately.
2. Click the Confirm button to remove
the message.
The message disappears. If the problem is not fixed, then the message
appears again shortly afterwards.
3. Do not proceed with the measurement until the problem is solved.

12.4.7Checking the quality of the measurement results in the adapted toolbench

In the main area of the user interface, the measurement results are displayed in the tools of the adapted toolbench. We recommend checking the quality of the results immediately after a measurement. Depending on
the results, it might be necessary to repeat the measurement with improved measurement setup or changed
parameters.
In the project tree and in numerous tools, the LaserDiagnosticsSoftware LDS enables evaluating measurement results. The results are automatically compared with limit and warning values and are marked accordingly by colors. For a detailed description of the project tree, the tools and the evaluation of the measurement
results, please refer to the separate operating manual of the LaserDiagnosticsSoftware LDS.

48

Revision 00 EN – 06/2021

MicroSpotMonitor MSM+

Fig. 12.1:

12.4.835,0(6

Display of measurement results in the tools of the adapted toolbench (example)

Remeasuring a caustic or plane (optional)

A caustic or plane can be remeasured using the Remeasure function. Note that this function is only available
if a device is connected.
When remeasuring a caustic, the existing measurement data is not overwritten. Rather, an additional caustic
measurement is created in the project tree. When remeasuring a plane, you will be asked beforehand if you
want to overwrite the plane selected in the project tree.
For a detailed description of the project tree, please refer to the separate operating manual of the LaserDiagnosticsSoftware LDS.

Revision 00 EN – 06/2021

49

35,0(6

MicroSpotMonitor MSM+

Proceed as follows(Example caustic measurement)::
1.

Click on the Projects tab.

2.

In the project tree, select the caustic measurement that you want toremeasure.

3.

Right-click to open the context menu
and select Remeasure.
The settings of the selected measurement are applied and displayed in the
Device control menu.

4.

Start a measurement by clicking theStart button.

The progress of the remeasurement isshown in the status display.

5.

50

After you have finished the measurement, click on the End remeasuring
button in the Advanced tab.

Revision 00 EN – 06/2021

MicroSpotMonitor MSM+

12.5

35,0(6

Performing single plane measurement

In the Single planes measuring mode, single planes are measured at selected z-positions. Measurement
window size and exposure can be set automatically or determined freely. You can also have the software
search the laser beam automatically in the entire measurement range.
To measure a custom caustic, several planes can be measured — either individually or by means of a series
measurement. To define the caustic measurement, an increment along the z-axis can be configured.
According to ISO 11146‑1, at least 10 planes shall be measured. Approximately half of the measurements
shall be distributed within one Rayleigh length on either side of the focus, and approximately half of themshall be distributed beyond two Rayleigh lengths from the focus.
By means of the variable integration time control, a large number of pulsed beams can be measured inquasi-cw operation in addition to cw laser beams. An exception are, for example, laser beams with a very
low pulse frequency. Trigger operation is available for measuring such beams. If this is enabled, the device
only measures within defined time periods. The laser pulse or the corresponding trigger signal marks the
beginning of such a period and the (freely adjustable) integration time marks its end. A measurement canbe triggered internally or externally. Internal signals are triggered by the photodiode integrated in the device.
Externally triggered signals enter the device via a BNC socket. For detailed information on the measurementof pulsed laser beams and the trigger operation, please refer to chapter 19.3 on page 101.
12.5.1

Preparatory steps

If you have not switched from anothermeasuring mode to here:
1.

Connect the device to the LaserDiagnosticsSoftware LDS according tochapter 12.2.1 on page 38.

2.

Open the Device control menu according to chapter 12.4.1 on page43.

3.

Select the Single planes measuringmode and open the adapted toolbench according to chapter 12.4.3 on
page 44.
The associated menu Device control
is opened.
The Single planes toolbench with thefollowing tools is opened:••

Caustic Analysis
Plane Analysis

Revision 00 EN – 06/2021

51

35,0(612.5.2

MicroSpotMonitor MSM+

Configuring settings

1.

Click on the Settings tab.

2.

Maintain the options according to the
explanations in Tab. 12.2.
Graphic
representation
Measurement range(thin line)

Measurement window(thick line)

OptionExplanation

Graphic representation

In a window in the upper area of the Settings tab, the measurement
plane is displayed graphically. Here you can see:• the entire measurable area (measurement range, thin lines)• the area to be recorded (measurement window, thick lines)• after a measurement a false-color image of the recorded area
You can make changes in the graphic representation as follows:
XX To create a new measurement window, position the mouse pointeranywhere within the measurement range. Drag while holding down
the left mouse button. Keep the mouse button pressed until themeasurement window meets your requirements.
The maximum size of the window depends, among other things,
on the magnification of the measuring objective (see chapter 7.1 on
page 16).
XX To move the measurement window to another location, position themouse pointer inside the measurement window. Drag while holding
down the right mouse button.
XX To zoom to the center of the graphic representation, first move themouse pointer over the graphic representation until the plus / minus
buttons appear. Then press the buttons.
XX To zoom in on the position of the mouse pointer, position the mousepointer anywhere within the graphic representation. Then turn themouse wheel.
XX To set the zoom section to the size of the measurement window,
position the mouse pointer inside the measurement window. Thendouble-click left.
XX To set the zoom section to the size of the measurement range,
position the mouse pointer outside the measurement window. Thendouble-click left.

z-Position in mm

Use one of the following options to set the desired z-position of theplane to be measured:
XX Enter a value in the input field.
XX Use the slider on the left side of the graphic representation.

Reset measurement window

XX Click this button to maximize the measurement window and simultaneously center it in the measurement range.

z-Increment in mm

XX If you want to measure multiple planes with fixed spacing, enter
the desired z-increment (see chapter 12.5.5, „Measuring further
planes“, on page 60).

Tab. 12.2:

52

Options in the Device control > Settings tab of the Single planes measuring mode

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

OptionExplanation

Power P in W *XX Enter the laser power used during measurement.
Only if the power is entered, a calculation of the power density distribution can be performed. Otherwise, the measured amplitudes are given
directly in counts.

autom. Measurement window

If this option is enabled, then the measurement window size will be set
automatically.
XX Set the check mark to enable the option.

Window size in mm

The maximum size of the measurement window depends, among otherthings, on the magnification of the measuring objective (see chapter 7.1
on page 16).
If the autom. Measurement window option is disabled, the size of themeasurement window can be adjusted manually. Use one of the following options:
XX Enter the length of a horizontal / vertical side in the input field on theleft / right.
XX Position the mouse pointer anywhere within the measurement
range and drag while holding down the left mouse button. Keep themouse button pressed until the measurement window meets yourrequirements.

Position in mm

Use one of the following options to adjust the position of the measurement window:
XX Enter the x-position / y-position of the center of the measurement
window in the input field on the left / right.
XX Position the mouse pointer within the measurement window. Thendrag while holding down the right mouse button.

Find beamThis option enables a measurement in which the laser beam is automatically searched for in the entire measurement range. The plane at thedefined z-position is then displayed in the graphic representation. Measurement window size, integration time, and filter level of the filter wheel(if available) are set automatically.
XX Click on the button to start the beam search.
Note that the determined measurement data will not be saved in the
project tree of the Projects tab.

autom. Exposure

If this option is enabled, the integration time is set automatically.
XX Set the check mark to enable the option.

Integration time in ms

If the autom. Exposure option is disabled, the integration time can be
set manually.
Use one of the following options:
XX Enter a value in the input field (0.006 ms to 225 ms).
XX Use the slider below the input field.
This option is available if an optional filter wheel is installed in the device.

Filter level

XX Select a filter level in the drop-down list.
The selected setting will only be active if the autom. filter adjustment
option is disabled.
The filter required for measurement depends on the wavelength andintensity of the laser beam to be measured. We recommend selecting
a filter level that achieves a detector modulation of between 60 % and80%.
Tab. 12.2:

Options in the Device control > Settings tab of the Single planes measuring mode

Revision 00 EN – 06/2021

53

35,0(6

MicroSpotMonitor MSM+

OptionExplanation

autom. filter adjustment

This option is available if an optional filter wheel is installed in the device.
If this option is enabled, then the filter levels are set automatically.
XX Set the check mark to enable the option.

Time series

A time series consists of several single plane measurements with thesame settings.

Number of measurements *XX Enter the desired number of single plane measurements of the timeseries.

Interval between measurements in s *XX Enter the pause between the single plane measurements of the timeseries. This is the time gap between the end of one measurement
and the start of the next.

Parameter settings

All settings in the Device control menu can be individually saved foreach device. The saving location is the local installation of the LaserDiagnosticsSoftware LDS.

Save current parameters

XX Click this button to save all current settings of the connected device.

Load last parameters

XX Click this button to load the last saved device configuration.

Tab. 12.2:

54

Options in the Device control > Settings tab of the Single planes measuring mode

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

12.5.3

Configuring advanced settings

1.

Click on the Advanced tab.

2.

Maintain the options according to the
explanations in Tab. 12.3.

OptionExplanation

Save device settings

All options marked with an asterisk in the Device control menu can besaved in the EEPROM of the device.
These and other options for saving / loading configurations are described in chapter 12.4.4 on page 45.

# Pixel in x/y *This option enables setting the resolution of the CCD sensor:
XX Enter the number of pixels in the x-direction / y-direction in the input
field on the left / right.

Low power modeThis option is only relevant when performing a beam search (Find beam
option, see chapter 12.5.2 on page 52). We recommend activating it
for low power laser beams (< 1 W).
If this option is enabled, the following initial values are selected during
beam search• Filter level of the filter wheel (if available): 0 (instead of 1 otherwise)• Integration time: 10 ms (instead of 1 ms otherwise).
XX Set the check mark to enable the option.

Calibrated wavelength(s) in nm *XX Select the calibrated wavelength in the drop-down list.
The values displayed correspond to the calibration points of the measuring objective. The correct value should be selected before each measurement to enable high measurement accuracy.

Used wavelength in nm *Use one of the following options to set the used wavelength of the laser:
XX Enter a value in the input field.
XX Use the slider below the input field.
This parameter must be distinguished from the factory calibrated wavelength of the measuring objective. The exact value should be entered,because it is used for calculating the significant beam quality factor M².
The wavelength used should approximately match the calibrated
wavelength. To enable high measurement accuracy, a pre­configured acceptance range must be observed. For example, if the calibration point
1 064 nm is selected, measurements can be taken in a range between
1 030 and 1 100 nm with high measurement accuracy.
Hence the value from the Calibrated wavelength in nm option is automatically adopted in the input field if a new selection was made there. If
this value is replaced by an impermissible high / low value, the impermissible value is automatically overwritten with the maximum / minimum
permissible value.

Magnification

This field displays the magnification of the measuring objective.

Focal length of focusing optics in mm *XX Enter the focal length used by the focusing optics of the laser
system.
If several planes of a caustic have been measured, the caustic fit and theentered focal length are used to calculate the raw beam diameter on thefocusing optics.

Tab. 12.3:

Options in the Device control > Advanced tab of the Single planes measuring mode

Revision 00 EN – 06/2021

55

35,0(6

MicroSpotMonitor MSM+

OptionExplanation

Averaging *If this option is enabled, different algorithms for averaging a plane measurement can be selected in the drop-down list below. Averaging over
several measurements can be useful, for example, when measuring alaser with significant power fluctuations.
1.
2.
•
•
•

Set the check mark to enable the option
Select an algorithm from the drop-down list:
Arithmetic mean: The measured values for each pixel are added
together and divided by the number of planes.
Max. intensity per pixel: The values from all the measurements arecompared for each pixel and only the maximum value for each one
is displayed.
Max. lines: The values from all the measurements are compared foreach line (meaning the line issuing from the measuring device in thex-direction for example) and only the maximum value for each one isdisplayed.

Number of averaged planes *XX With the Averaging option enabled, enter the number of planemeasurements for averaging.

TriggerDrop-down area for displaying the options of the trigger operation.
The trigger operation is suitable for measuring special pulsed beams.
Detailed information on this topic can be found in the chapter 19.3 on
page 101.

Drop-down list for trigger selection

This drop-down list is only visible if the drop-down area for displaying theoptions of the trigger operation is open.
You can select from the following options:• UseNoTrigger: Switches to the default cw / quasi-cw operation.
• UsePhotoTrigger: Switches to a trigger operation in which themeasurement is triggered internally. The signals come from thephotodiode built into the device.
• UseExternalTrigger: Switches to a trigger operation in which themeasurement is triggered externally. The trigger signals enter thedevice via the BNC socket.

TriggerDelay in ms *This drop-down list is only visible if the drop-down area for displaying theoptions of the trigger operation is open.
The trigger delay specifies the period between the trigger signal and the
beginning of the integration time. Use one of the following options to set
the trigger delay time:
XX Enter a value in the input field (0.012 ms to 400 ms).
XX Use the slider below the input field.

TriggerLevel *This drop-down list is only visible if the drop-down area for displaying theoptions of the trigger operation is open.
The trigger level is the threshold value for triggering a signal via the internal photodiode. Use one of the following options to set the trigger level:
XX Enter a value in the input field.
XX Use the slider below the input field.
You can determine the threshold value suitable for a measurement task
as follows:
1. Set the trigger level to the maximum value.
2. Decrease the value step by step until the device receives sometrigger signals (lower trigger level).
3. Increase the value until the device does not receive any trigger
signals (upper trigger level).
4. Calculate the trigger level as the arithmetic mean of the two limit
values.

Tab. 12.3:

56

Options in the Device control > Advanced tab of the Single planes measuring mode

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

OptionExplanation

Locked area

Locked area means a restriction of the traversing range in the z-direction. The lower limit of the enabled traversing range is always home
position. The upper limit can be set freely.

Maximum z-Position in mm *1. Use one of the following options to set the locked area:
XX Enter the upper limit of the permitted z-traversing range in the input
field.
XX Use the slider below the input field.
We recommend saving a locked area in the device, if it is safety-relevant:
2. If you want to save the locked area (and the other options marked
with an asterisk) in the device, click the Save device settings button.
xx The settings are retained even if the device is switched off or disconnected from the power source.

Tab. 12.3:

Options in the Device control > Advanced tab of the Single planes measuring mode

Revision 00 EN – 06/2021

57

35,0(612.5.4MicroSpotMonitor MSM+

Measuring a plane

DANGER
Serious eye or skin injury due to laser radiation
X Observe the warning messages in chapter 12.1 on page 37.
1.

Switch on the laser.

2.

Click on the Settings tab.

3. Click on the Find beam button.
xx The laser beam is automaticallysearched for in the entire measurement range. Measurement window
size, integration time and filter levelof the filter wheel (if available) are set
automatically.
If the search is successful, the beam
is displayed in the graphic representation.
If the beam is not displayed:
4. Select the Low power mode option
or increase the integration time or
select a weaker filter of the filter wheel(if available).
5. Select a different z-position.
6. Check again the correct alignment of
the device on the x-y plane according
to chapter 8.3.4 on page 26.
7. Increase the laser power (step bystep).

As soon as the beam is displayed:
8. Click the Start button.
xx The measurement begins.
9.

58

Optional:
If necessary, click the Stop button toend the measurement prematurely.

Revision 00 EN – 06/2021

MicroSpotMonitor MSM+

35,0(6

During the measurement, the progress is shown in the following indicators:
Measuring plane
While the indicator is rotating, the measurement is performed.
Measurement completed
After successful measurement, the indicator lights up green.
10. Switch off the laser after the measurement is completed, unless you wantto perform further measurements.
Averaging (if enabled)
The indication shows the measured
planes that are used to average a measured value.
Adjusting size and position of the measurement window (optional)
11. Make sure that the autom. Measurement window option is not enabled.
Otherwise, the manual setting may beoverwritten when starting a measurement.
12. Use one of the following options toadjust the size of the measurement
window:
XX Enter the length of a horizontal / vertical side in the input field on the left /right.
XX Position the mouse pointer anywhere within the measurement range
and drag while holding down theleft mouse button. Keep the mousebutton pressed until the measurement
window meets your requirements.
13. Use one of the following options toadjust the position of the measurement window:
XX Enter the x-position / y-position of thecenter of the measurement window in
the input field on the left / right.
XX Position the mouse pointer within themeasurement window. Then dragwhile holding down the right mousebutton.
14. Click the Start button to perform themeasurement in the manually customized measurement window.
15. Switch off the laser after the measurement is completed, unless you wantto perform further measurements.

Revision 00 EN – 06/2021

59

35,0(612.5.5MicroSpotMonitor MSM+

Measuring further planes

Directly after a plane measurement, further measurements at other z-positions can be performed. In this way,a free caustic can be measured.
Single measurement at a specificz‑position
1.

Click on the Settings tab.

2.

In the z-Position in mm field, enter
the desired position of the next plane
to be measured.

3.

Start and stop the measurement
according to chapter 12.5.4 on page
58.

Single measurements using z-increment spacing
1.
2.

Click on the Settings tab.
Enter the spacing for the further
measurements in the z-Increment in
mm field.
3. Start a measurement by clicking on
the Start button and wait until themeasurement is completed (seechapter 12.5.4 on page 58).
xx The measured plane is one z‑increment away from the previously
measured plane.
4. Click the start button again and wait
until the measurement is completed(see chapter 12.5.4 on page 58).
xx The measured plane is one z‑increment away from the previously
measured plane.
5. Repeat the last step as often as you
like.
Series measurement using z-increment
spacing
The combination of the Time series andz‑Increment in mm options enables
measuring a free caustic in one run.
1.
2.
3.

60

Click on the Settings tab.
Enter the spacing for the planes to bemeasured in the z-Increment in mm
field.
In the Number of measurements
and Interval between measurements in s fields, enter the numberof measurements and the pause. The
pause is the time between the endof one measurement and the start of
the next.
Start and stop the series measurement according to chapter 12.5.4 on
page 58.

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

12.6

Performing continuous plane measurement

In the Monitor measuring mode, measuring planes can be continuously observed in a false-color image. The
laser beam can be automatically searched by the software in the entire measurement range. After a successful search the measurement can be run as long as desired. During the measurement, data is continuously
being read out and displayed in the grapic view with a high frame rate. The z-position of the camera housing
can be changed during measurement. Measurement data is not saved in the project tree of the Projects tab.
12.6.1

Preparatory steps

If you have not switched from anothermeasuring mode to here:
1.

Connect the device to the LaserDiagnosticsSoftware LDS according tochapter 12.2.1 on page 38.

2.

Open the Device control menu according to chapter 12.4.1 on page43.

3.

Select the Monitor measuring modeand open the adapted toolbenchaccording to chapter 12.4.3 on page
44.
The associated menu Device control
is opened.
The Monitor toolbench with theFalse-color image tool is opened.

12.6.2

Configuring settings

1.

Click on the Settings tab.

2.

Maintain the options according to the
explanations in Tab. 12.4.
Graphic
representation
Measurement range(thin line)

Measurement window(thick line)

Revision 00 EN – 06/2021

61

35,0(6

MicroSpotMonitor MSM+

OptionExplanation

Graphic representation

In a window in the upper area of the Settings tab, the measurement
plane is displayed graphically. Here you can see:• the entire measurable area (measurement range, thin lines)• the area to be recorded (measurement window, thick lines)• after a measurement a false-color image of the recorded area
You can make changes in the graphic representation as follows:
XX To create a new measurement window, position the mouse pointeranywhere within the measurement range. Drag while holding down
the left mouse button. Keep the mouse button pressed until themeasurement window meets your requirements.
The maximum size of the window depends, among other things,
on the magnification of the measuring objective (see chapter 7.1 on
page 16).
XX To move the measurement window to another location, position themouse pointer inside the measurement window. Drag while holding
down the right mouse button.
XX To zoom to the center of the graphic representation, first move themouse pointer over the graphic representation until the plus / minus
buttons appear. Then press the buttons.
XX To zoom in on the position of the mouse pointer, position the mousepointer anywhere within the graphic representation. Then turn themouse wheel.
XX To set the zoom section to the size of the measurement window,
position the mouse pointer inside the measurement window. Thendouble-click left.
XX To set the zoom section to the size of the measurement range,
position the mouse pointer outside the measurement window. Thendouble-click left.

z-Position in mm

Use one of the following options to set the desired z-position of theplane to be measured:
XX Enter a value in the input field.
XX Use the slider on the left side of the graphic representation.

Reset measurement window

XX Click this button to maximize the measurement window and simultaneously center it in the measurement range.

Window size in mm

The maximum size of the window depends, among other things, on
the magnification of the measuring objective (see chapter 7.1 on page16).
Use one of the following options to adjust the size of the measurement
window:
XX Enter the length of a horizontal / vertical side in the input field on theleft / right.
XX Position the mouse pointer anywhere within the measurement
range and drag while holding down the left mouse button. Keep themouse button pressed until the measurement window meets yourrequirements.

Position in mm

Tab. 12.4:

62

Use one of the following options to adjust the position of the measurement window:
XX Enter the x-position / y-position of the center of the measurement
window in the input field on the left / right.
XX Position the mouse pointer within the measurement window. Thendrag while holding down the right mouse button.

Options in the Device control > Settings tab of the Monitor measuring mode

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

OptionExplanation

Find beamThis option enables a measurement in which the laser beam is automatically searched for in the entire measurement range. The plane at thedefined z-position is then displayed in the graphic representation. Measurement window size, integration time, and filter level of the filter wheel(if available) are set automatically.
XX Click on the button to start the beam search.
Note that the determined measurement data will not be saved in the
project tree of the Projects tab.

autom. Exposure

If this option is enabled, then the integration time is set automatically.
XX Set the check mark to enable the option.

Integration time in ms

If the autom. Exposure option is disabled, the integration time can be
set manually.
Use one of the following options:
XX Enter a value in the input field (0.006 ms to 225 ms).
XX Use the slider below the input field.
This option is available if an optional filter wheel is installed in the device.

Filter level

XX Select a filter level in the drop-down list.
The selected setting will only be active if the autom. filter adjustment
option is disabled.
The filter required for measurement depends on the wavelength andintensity of the laser beam to be measured. We recommend selecting
a filter level that achieves a detector modulation of between 60 % and80%.
autom. filter adjustment

This option is available if an optional filter wheel is installed in the device.
If this option is enabled, then the filter levels are set automatically.
XX Set the check mark to enable the option.
If this option is enabled, the plane is displayed with a higher frame rate.
Note, however, that no corrective measurements are then performed.
The measurement data may therefore be affected by measurement
artefacts such as the readout noise "smear effect". In addition, no radii
are displayed in the False-color image tool.

Fast ModeXX Set the check mark to enable the option.
Parameter settings

All settings in the Device control menu can be individually saved foreach device. The saving location is the local installation of the LaserDiagnosticsSoftware LDS.

Save current parameters

XX Click this button to save all current settings of the connected device.

Load last parameters

XX Click this button to load the last saved device configuration.

Tab. 12.4:

Options in the Device control > Settings tab of the Monitor measuring mode

Revision 00 EN – 06/2021

63

35,0(612.6.3

MicroSpotMonitor MSM+

Configuring advanced settings

1.

Click on the Advanced tab.

2.

Maintain the options according to the
explanations in Tab. 12.5.

OptionExplanation

Save device settings

All options marked with an asterisk in the Device control menu can besaved in the EEPROM of the device.
These and other options for saving / loading configurations are described in chapter 12.4.4 on page 45.

# Pixel in x/y *This option enables setting the resolution of the CCD sensor:
XX Enter the number of pixels in the x-direction / y-direction in the input
field on the left / right.

Magnification

This field displays the magnification of the measuring objective.

Low power modeThis option is only relevant when performing a beam search (Find beam
option, see chapter 12.6.2 on page 61). We recommend activating it
for low power laser beams (< 1 W).
If this option is enabled, the following initial values are selected during
beam search• Filter level of the filter wheel (if available): 0 (instead of 1 otherwise)• Integration time: 10 ms (instead of 1 ms otherwise).
XX Set the check mark to enable the option.

Locked area

Locked area means a restriction of the traversing range in the z-direction. The lower limit of the enabled traversing range is always home
position. The upper limit can be set freely.

Maximum z-Position in mm *1. Use one of the following options to set the locked area:
XX Enter the upper limit of the permitted z-traversing range in the input
field.
XX Use the slider below the input field.
We recommend saving a locked area in the device, if it is safety-relevant:
2. If you want to save the locked area (and the other options marked
with an asterisk) in the device, click the Save device settings button.
xx The settings are retained even if the device is switched off or disconnected from the power source.

Tab. 12.5:

64

Options in the Device control > Advanced tab of the Monitor measuring mode

Revision 00 EN – 06/2021

MicroSpotMonitor MSM+

12.6.435,0(6

Measuring a plane continuously

DANGER
Serious eye or skin injury due to laser radiation
X Observe the warning messages in chapter 12.1 on page 37.
If you use continuous plane measurement to align the device, observe the following:
X Align the device using a pilot laser where no dangerous reflections can occur.
X Only align the device using a laser where dangerous reflections can occur (laser class 4) if
the process is carried out remotely behind a separating protective equipment. The protective equipment must be suitable for blocking the radiation or attenuating it to a non-hazardous level.
1.

Switch on the laser.

2.

Click on the Settings tab.

3. Click on the Find beam button.
xx The laser beam is automaticallysearched for in the entire measurement range. Measurement window
size, integration time and filter levelof the filter wheel (if available) are set
automatically.
If the search is successful, the beam
is displayed in the graphic representation.
If the beam is not displayed:
4. Select the Low power mode option
or increase the integration time or
select a weaker filter of the filter wheel(if available).
5. Select a different z-position.
6. Check again the correct alignment of
the device on the x-y plane according
to chapter 8.3.4 on page 26.
7. Increase the laser power (step bystep).

As soon as the beam is displayed:
8. Click the Start button.
xx The measurement begins.

Revision 00 EN – 06/2021

65

35,0(6

MicroSpotMonitor MSM+

Data is continuously read out from thepreviously set measurement window
and displayed with a high frame ratein the false-color image.
9.

To stop the measurement, click on
the Stop button.

10. Switch off the laser after the measurement is completed, unless you wantto perform further measurements.

Adjusting size and position of the measurement window (optional)
11. Make sure that the autom. Measurement window option is not enabled.
Otherwise, the manual setting may beoverwritten when starting a measurement.
12. Use one of the following options toadjust the size of the measurement
window:
XX Enter the length of a horizontal / vertical side in the input field on the left /right.
XX Position the mouse pointer anywhere within the measurement range
and drag while holding down theleft mouse button. Keep the mousebutton pressed until the measurement
window meets your requirements.
13. Use one of the following options toadjust the position of the measurement window:
XX Enter the x-position / y-position of thecenter of the measurement window in
the input field on the left / right.
XX Position the mouse pointer within themeasurement window. Then dragwhile holding down the right mousebutton.
14. Click the Start button to perform themeasurement in the manually customized measurement window.
15. To stop the measurement, click on
the Stop button.
16. Switch off the laser after the measurement is completed, unless you wantto perform further measurements.

66

Revision 00 EN – 06/2021

MicroSpotMonitor MSM+

12.7

35,0(6

Performing manual caustic measurement

In the Manual caustic measuring mode, only the z‑range and the number of plane measurements have tobe specified. All other required settings are automatically determined and adjusted. In addition, advanced
settings can be applied.
According to ISO 11146‑1, at least 10 planes shall be measured. Approximately half of the measurements
shall be distributed within one Rayleigh length on either side of the focus, and approximately half of themshall be distributed beyond two Rayleigh lengths from the focus.
For two reasons, an odd number of measuring planes makes it more likely that the focal plane will be measured. First, the LaserDiagnosticsSoftware LDS always sets the spacing between the measuring planes
equal. Second, the measuring range along the z-axis is almost always symmetrical around the focus. We
recommend measuring at least 21 planes within 6 Rayleigh lengths.
By means of the variable integration time control, not only cw laser beams but also a multitude of pulsed
beams can be measured in quasi-cw operation. An exception are, for example, laser beams with a very
low pulse frequency. Trigger operation is available for measuring such beams. If this is enabled, the device
only measures within defined time periods. The laser pulse or the corresponding trigger signal marks the
beginning of such a period and the (freely adjustable) integration time marks its end. A measurement canbe triggered internally or externally. Internal signals are triggered by the photodiode integrated in the device.
Externally triggered signals enter the device via a BNC socket. For detailed information on the measurementof pulsed laser beams and the trigger operation, please refer to chapter 19.3 on page 101.
12.7.1

Preparatory steps

If you have not switched from anothermeasuring mode to here:
1.

Connect the device to the LaserDiagnosticsSoftware LDS according tochapter 12.2.1 on page 38.

2.

Open the Device control menu
according to chapter 12.4.1 on page43.

3.

Select the Manual caustic measuringmode and open the adapted toolbench according to chapter 12.4.3 on
page 44.
The associated menu Device control
is opened.
The Manual caustic toolbench withthe following tools is opened:••

Caustic Analysis
Plane Analysis

12.7.2

Configuring settings

1.

Click on the Settings tab.

2.

Maintain the options according to the
explanations in Tab. 12.6.

Revision 00 EN – 06/2021

67

35,0(6

MicroSpotMonitor MSM+

OptionExplanation

Optimized measurement settings

If this option is activated, the measurement takes shorter time. Fewerprocess steps are required, since the initial settings for a plane measurement are taken from the settings of the previous plane measurement.
Please note, however, that beam artefacts may not be adequately
detected in the single plane measurements due to the transfer of thesettings.
XX Set the check mark to activate the option.

Number of planes *XX Enter the number of planes to be measured.

z-Axis position (z1 / z2) in mm *This option enables configuring the z‑range in which the measurement is
to be performed.
XX Regarding the traversing range in which the measurement is to be
performed, enter the lower limit z1 in the left field and the upper limit
z2 in the right field.
XX Alternatively, use the sliders.

Caustic suggestion

When a caustic measurement is completed, a z-range is displayed inthese fields. The limits of the suggested z-range have a distance of± 3 Rayleigh lengths to the determined beam focus. This z-range is
optimized according to Primes quality criteria.

Use

XX Click this button to transfer the z-values displayed in the Caustic
suggestion fields to the z-Axis position (z1 / z2) in mm fields.

Reset z-Axis position

XX Click this button to reset the z-axis position to the default values(z1 = 0 und z2 = 6).

Power P in W *XX Enter the laser power used during measurement.
Only if the power is entered, a calculation of the power density distribution can be performed. Otherwise, the measured amplitudes are given
directly in counts.
This option is available if an optional filter wheel is installed in the device.

Filter level

XX Select a filter level in the drop-down list.
The selected setting will only be active if the autom. filter adjustment
option is disabled.
The filter required for measurement depends on the wavelength andintensity of the laser beam to be measured. We recommend selecting
a filter level that achieves a detector modulation of between 60 % and80%.
autom. filter adjustment

This option is available if an optional filter wheel is installed in the device.
If this option is enabled, then the filter levels are set automatically.
XX Set the check mark to enable the option.

Time series

A time series consists of several caustic measurements with the samesettings.

Number of measurements *XX Enter the desired number of caustic measurements of the timeseries.

Interval between measurements in s *XX Enter the pause between the caustic measurements of the timeseries. This is the time gap between the end of one measurement
and the start of the next.

Tab. 12.6:

68

Options in the Device control > Settings tab of the Manual caustic measuring mode

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

12.7.3

Configuring advanced settings

1.

Click on the Advanced tab.

2.

Maintain the options according to the
explanations in Tab. 12.7.

OptionExplanation

Save device settings

All options marked with an asterisk in the Device control menu can besaved in the EEPROM of the device.
These and other options for saving / loading configurations are described in chapter 12.4.4 on page 45.

# Pixel in x/y *This option enables setting the resolution of the CCD sensor:
XX Enter the number of pixels in the x-direction / y-direction in the input
field on the left / right.

Averaging *If this option is enabled, different algorithms for averaging a plane measurement can be selected in the drop-down list below. Averaging over
several measurements can be useful, for example, when measuring alaser with significant power fluctuations.
1.
2.
•
•
•

Set the check mark to enable the option
Select an algorithm from the drop-down list:
Arithmetic mean: The measured values for each pixel are added
together and divided by the number of planes.
Max. intensity per pixel: The values from all the measurements arecompared for each pixel and only the maximum value for each one
is displayed.
Max. lines: The values from all the measurements are compared foreach line (meaning the line issuing from the measuring device in thex-direction for example) and only the maximum value for each one isdisplayed.

Number of averaged planes *XX With the Averaging option enabled, enter the number of planemeasurements for averaging.

Low power mode

We recommend enabling this option for low power laser beams (< 1 W).
If this option is enabled, the following initial values are selected during
beam search• Filter level of the filter wheel (if available): 0 (instead of 1 otherwise)• Integration time: 10 ms (instead of 1 ms otherwise).
XX Set the check mark to enable the option.

Calibrated wavelength(s) in nm *XX Select the calibrated wavelength in the drop-down list.
The values displayed correspond to the calibration points of the measuring objective. The correct value should be selected before each measurement to enable high measurement accuracy.

Tab. 12.7:

Options in the Device control > Advanced tab of the Manual caustic measuring mode

Revision 00 EN – 06/2021

69

35,0(6

MicroSpotMonitor MSM+

OptionExplanation

Used wavelength in nm *Use one of the following options to set the used wavelength of the laser:
XX Enter a value in the input field.
XX Use the slider below the input field.
This parameter must be distinguished from the factory calibrated wavelength of the measuring objective. The exact value should be entered,because it is used for calculating the significant beam quality factor M².
The wavelength used should approximately match the calibrated
wavelength. To enable high measurement accuracy, a pre­configured acceptance range must be observed. For example, if the calibration point
1 064 nm is selected, measurements can be taken in a range between
1 030 and 1 100 nm with high measurement accuracy.
Hence the value from the Calibrated wavelength in nm option is automatically adopted in the input field if a new selection was made there. If
this value is replaced by an impermissible high / low value, the impermissible value is automatically overwritten with the maximum / minimum
permissible value.

Magnification

This field displays the magnification of the measuring objective.

Focal length of focusing optics in mm *XX Enter the focal length used by the focusing optics of the laser
system.
The caustic fit and the entered focal length are used to calculate the raw
beam diameter on the focusing optics.
Drop-down area for displaying the options of the trigger operation.

Trigger

The trigger operation is suitable for measuring special pulsed beams.
Detailed information on this topic can be found in the chapter 19.3 on
page 101.
Drop-down list for trigger selection

This drop-down list is only visible if the drop-down area for displaying theoptions of the trigger operation is open.
You can select from the following options:• UseNoTrigger: Switches to the default cw / quasi-cw operation.
• UsePhotoTrigger: Switches to a trigger operation in which themeasurement is triggered internally. The signals come from thephotodiode built into the device.
• UseExternalTrigger: Switches to a trigger operation in which themeasurement is triggered externally. The trigger signals enter thedevice via the BNC socket.

TriggerDelay in ms *This drop-down list is only visible if the drop-down area for displaying theoptions of the trigger operation is open.
The trigger delay specifies the period between the trigger signal and the
beginning of the integration time. Use one of the following options to set
the trigger delay time:
XX Enter a value in the input field (0.012 ms to 400 ms).
XX Use the slider below the input field.

Tab. 12.7:

70

Options in the Device control > Advanced tab of the Manual caustic measuring mode

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

OptionExplanation

TriggerLevel *This drop-down list is only visible if the drop-down area for displaying theoptions of the trigger operation is open.
The trigger level is the threshold value for triggering a signal via the internal photodiode. Use one of the following options to set the trigger level:
XX Enter a value in the input field.
XX Use the slider below the input field.
You can determine the threshold value suitable for a measurement task
as follows:
1. Set the trigger level to the maximum value.
2. Decrease the value step by step until the device receives sometrigger signals (lower trigger level).
3. Increase the value until the device does not receive any trigger
signals (upper trigger level).
4. Calculate the trigger level as the arithmetic mean of the two limit
values.

Locked area

Locked area means a restriction of the traversing range in the z-direction. The lower limit of the enabled traversing range is always home
position. The upper limit can be set freely.

Maximum z-Position in mm *1. Use one of the following options to set the locked area:
XX Enter the upper limit of the permitted z-traversing range in the input
field.
XX Use the slider below the input field.
We recommend saving a locked area in the device, if it is safety-relevant:
2. If you want to save the locked area (and the other options marked
with an asterisk) in the device, click the Save device settings button.
xx The settings are retained even if the device is switched off or disconnected from the power source.

Tab. 12.7:

Options in the Device control > Advanced tab of the Manual caustic measuring mode

Revision 00 EN – 06/2021

71

35,0(612.7.4MicroSpotMonitor MSM+

Measuring a caustic manually

DANGER
Serious eye or skin injury due to laser radiation
X Observe the warning messages in chapter 12.1 on page 37.
1.

Switch on the laser.

2. Click the Start button.
xx The measurement begins.
3.

Optional:
If necessary, click the Stop button toend the measurement prematurely.
During the measurement, the progress is shown in the following indicators:

Measuring caustic
While the indicator is rotating, the measurement is performed. The measurement
parameters are optimized according toPrimes quality criteria.
Measurement completed
After successful measurement, the indicator lights up green.
4.

Switch off the laser after the measurement is completed, unless you wantto perform further measurements.

Averaging (if enabled)
The indication shows the measured
planes that are used to average a measured value.
Applying a caustic suggestion (optional)
After the measurement is completed,a z-range is displayed in the Caustic
suggestion fields. The limits of thesuggested z-range have a distanceof ± 3 Rayleigh lengths to the determined beam focus.
This z-range is optimized according
to Primes quality criteria.
5.

If you want to apply this suggestion,
click the Use button.
The suggested limit values z1 / z2 aretransfered to the z-Axis position (z1 /z2) in mm fields.

6.

Click the Start button again to perform the measurement in the suggested z-range.

7.

Switch off the laser after the measurement is completed, unless you wantto perform further measurements.

72

Revision 00 EN – 06/2021

MicroSpotMonitor MSM+

12.8

35,0(6

Performing automatic caustic measurement

In the Automatic caustic measuring mode, only the initial z-position of the pre-caustic measurement andthe number of measuring planes of the actual caustic measurement are not selected automatically. The zrange as well as all other required settings are determined and adjusted automatically. In addition, advanced
settings can be applied.
According to ISO 11146‑1, at least 10 planes shall be measured. Approximately half of the measurements
shall be distributed within one Rayleigh length on either side of the focus, and approximately half of themshall be distributed beyond two Rayleigh lengths from the focus.
For two reasons, an odd number of measuring planes makes it more likely that the focal plane will be measured. First, the LaserDiagnosticsSoftware LDS always sets the spacing between the measuring planes
equal. Second, the measuring range along the z-axis is almost always symmetrical around the focus. We
recommend measuring at least 21 planes within 6 Rayleigh lengths.
By means of the variable integration time control, not only cw laser beams but also a multitude of pulsed
beams can be measured in quasi-cw operation. An exception are, for example, laser beams with a very
low pulse frequency. Trigger operation is available for measuring such beams. If this is enabled, the device
only measures within defined time periods. The laser pulse or the corresponding trigger signal marks the
beginning of such a period and the (freely adjustable) integration time marks its end. A measurement canbe triggered internally or externally. Internal signals are triggered by the photodiode integrated in the device.
Externally triggered signals enter the device via a BNC socket. For detailed information on the measurementof pulsed laser beams and the trigger operation, please refer to chapter 19.3 on page 101.
12.8.1

Preparatory steps

If you have not switched from anothermeasuring mode to here:
1.

Connect the device to the LaserDiagnosticsSoftware LDS according tochapter 12.2.1 on page 38.

2.

Open the Device control menu according to chapter 12.4.1 on page43.

3.

Select the Automatic caustic measuring mode and open the adapted
toolbench according to chapter
12.4.3 on page 44.
The associated menu Device control
is opened.
The Automatic caustic toolbenchwith the following tools is opened:••

Caustic Analysis
Plane Analysis

Revision 00 EN – 06/2021

73

35,0(612.8.2

MicroSpotMonitor MSM+

Configuring settings

1.

Click on the Settings tab.

2.

Maintain the options according to the
explanations in Tab. 12.8.

OptionExplanation

z-Position in mm

Use one of the following options to set the initial z-position for the precaustic measurement:
XX Enter a value in the input field.
XX Use the slider below the input field.

Parking position after caustic

XX In the drop-down list, select the parking position to which the camera housing will be moved after the caustic measurement.
You can select from the following options:• Focus: The camera housing is moved back to the position of thedetermined beam focus.
• Start position: The camera housing is moved back to the start
position.
• Final position: The camera housing remains in the final position.
The selected position is also the start position for the pre-caustic measurement of the next measurement (unless you enter a different value inthe z-Position in mm field).

Power P in W *XX Enter the laser power used during measurement.
Only if the power is entered, a calculation of the power density distribution can be performed. Otherwise, the measured amplitudes are given
directly in counts.
This option is available if an optional filter wheel is installed in the device.

Filter level

XX Select a filter level in the drop-down list.
The selected setting will only be active if the autom. filter adjustment
option is disabled.
The filter required for measurement depends on the wavelength andintensity of the laser beam to be measured. We recommend selecting
a filter level that achieves a detector modulation of between 60 % and80%.
autom. filter adjustment

This option is available if an optional filter wheel is installed in the device.
If this option is enabled, then the filter levels are set automatically.
XX Set the check mark to enable the option.

Time series

A time series consists of several caustic measurements with the samesettings.

Number of measurements *XX Enter the desired number of caustic measurements of the timeseries.

Interval between measurements in s *XX Enter the pause between the caustic measurements of the timeseries. This is the time gap between the end of one measurement
and the start of the next.

Tab. 12.8:

74

Options in the Device control > Settings tab of the Automatic caustic measuring mode

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

12.8.3

Configuring advanced settings

1.

Click on the Advanced tab.

2.

Maintain the options according to the
explanations in Tab. 12.9.

OptionExplanation

Save device settings

All options marked with an asterisk in the Device control menu can besaved in the EEPROM of the device.
These and other options for saving / loading configurations are described in chapter 12.4.4 on page 45.

# Pixel in x/y *This option enables setting the resolution of the CCD sensor:
XX Enter the number of pixels in the x-direction / y-direction in the input
field on the left / right.

Number of planes *XX Enter the number of planes to be measured.

Low power mode

We recommend enabling this option for low power laser beams (< 1 W).
If this option is enabled, the following initial values are selected during
beam search• Filter level of the filter wheel (if available): 0 (instead of 1 otherwise)• Integration time: 10 ms (instead of 1 ms otherwise).
XX Set the check mark to enable the option.

Calibrated wavelength(s) in nm *XX Select the calibrated wavelength in the drop-down list.
The values displayed correspond to the calibration points of the measuring objective. The correct value should be selected before each measurement to enable high measurement accuracy.

Used wavelength in nm *Use one of the following options to set the used wavelength of the laser:
XX Enter a value in the input field.
XX Use the slider below the input field.
This parameter must be distinguished from the factory calibrated wavelength of the measuring objective. The exact value should be entered,because it is used for calculating the significant beam quality factor M².
The wavelength used should approximately match the calibrated
wavelength. To enable high measurement accuracy, a pre­configured acceptance range must be observed. For example, if the calibration point
1 064 nm is selected, measurements can be taken in a range between
1 030 and 1 100 nm with high measurement accuracy.
Hence the value from the Calibrated wavelength in nm option is automatically adopted in the input field if a new selection was made there. If
this value is replaced by an impermissible high / low value, the impermissible value is automatically overwritten with the maximum / minimum
permissible value.

Magnification

This field displays the magnification of the measuring objective.

Focal length of focusing optics in mm *XX Enter the focal length used by the focusing optics of the laser
system.
The caustic fit and the entered focal length are used to calculate the raw
beam diameter on the focusing optics.

Tab. 12.9:

Options in the Device control > Advanced tab of the Automatic caustic measuring mode

Revision 00 EN – 06/2021

75

35,0(6

MicroSpotMonitor MSM+

OptionExplanation

TriggerDrop-down area for displaying the options of the trigger operation.
The trigger operation is suitable for measuring special pulsed beams.
Detailed information on this topic can be found in the chapter 19.3 on
page 101.

Drop-down list for trigger selection

This drop-down list is only visible if the drop-down area for displaying theoptions of the trigger operation is open.
You can select from the following options:• UseNoTrigger: Switches to the default cw / quasi-cw operation.
• UsePhotoTrigger: Switches to a trigger operation in which themeasurement is triggered internally. The signals come from thephotodiode built into the device.
• UseExternalTrigger: Switches to a trigger operation in which themeasurement is triggered externally. The trigger signals enter thedevice via the BNC socket.

TriggerDelay in ms *This drop-down list is only visible if the drop-down area for displaying theoptions of the trigger operation is open.
The trigger delay specifies the period between the trigger signal and the
beginning of the integration time. Use one of the following options to set
the trigger delay time:
XX Enter a value in the input field (0.012 ms to 400 ms).
XX Use the slider below the input field.

TriggerLevel *This drop-down list is only visible if the drop-down area for displaying theoptions of the trigger operation is open.
The trigger level is the threshold value for triggering a signal via the internal photodiode. Use one of the following options to set the trigger level:
XX Enter a value in the input field.
XX Use the slider below the input field.
You can determine the threshold value suitable for a measurement task
as follows:
1. Set the trigger level to the maximum value.
2. Decrease the value step by step until the device receives sometrigger signals (lower trigger level).
3. Increase the value until the device does not receive any trigger
signals (upper trigger level).
4. Calculate the trigger level as the arithmetic mean of the two limit
values.

Locked area

Tab. 12.9:

76

Locked area means a restriction of the traversing range in the z-direction. The lower limit of the enabled traversing range is always home
position. The upper limit can be set freely.

Options in the Device control > Advanced tab of the Automatic caustic measuring mode

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

OptionExplanation

Maximum z-Position in mm *1. Use one of the following options to set the locked area:
XX Enter the upper limit of the permitted z-traversing range in the input
field.
XX Use the slider below the input field.
We recommend saving a locked area in the device, if it is safety-relevant:
2. If you want to save the locked area (and the other options marked
with an asterisk) in the device, click the Save device settings button.
xx The settings are retained even if the device is switched off or disconnected from the power source.

Tab. 12.9:

Options in the Device control > Advanced tab of the Automatic caustic measuring mode

Revision 00 EN – 06/2021

77

35,0(612.8.4MicroSpotMonitor MSM+

Measuring a caustic automatically

DANGER
Serious eye or skin injury due to laser radiation
X Observe the warning messages in chapter 12.1 on page 37.
1.

Switch on the laser.

2. Click the Start button.
xx The measurement begins.
3.

Optional:
If necessary, click the Stop button toend the measurement prematurely.
During the measurement, the progress is shown in the following indicators:

Pre-caustic
While the indicator is rotating, the measurement parameters are determined
automatically (for example measurement
window position, measurement window size, integration time, z-range). The
measurement parameters are optimized
according to Primes quality criteria.
After successful pre-caustic measurement, the indicator lights up green.
Measuring caustic
While the indicator is rotating, the actual
measurement is performed.
Measurement completed
After successful measurement, the indicator lights up green.
4.

78

Switch off the laser after the measurement is completed, unless you wantto perform further measurements.

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

12.9

Monitoring beam pointing stability

In the Beam pointing measuring mode, the measuring points of a series of measurements are displayedin coordinates. The measuring points show the position of the beam center on the x-y plane as well as theangle of the beam incidence to the x-y plane. This display can be used to monitor the beam pointing stability.
During the measurement, the device alternately performs plane measurements at positions z1 and z2. These
positions are determined automatically in a preparatory step, but can also be specified manually. Likewise,
the number of measuring points displayed in the coordinates can be specified.
12.9.1

Preparatory steps

If you have not switched from anothermeasuring mode to here:
1.

Connect the device to the LaserDiagnosticsSoftware LDS according tochapter 12.2.1 on page 38.

2.

Open the Device control menu according to chapter 12.4.1 on page43.

3.

Select the Beam pointing measuringmode and open the adapted toolbench according to chapter 12.4.3 on
page 44.
The associated menu Device control
is opened.
The Beam pointing toolbench withthe following tools is opened:••

Beam Pointing Stability
False-color Image

12.9.2

Configuring settings

1.

Click on the Settings tab.

2.

Maintain the options according to the
explanations in Tab. 12.10.

OptionExplanation

z-Position in mm

Use one of the following options to specify the desired initial z-positionof the camera housing for the pre-caustic measurement:
XX Enter a value in the input field.
XX Use the slider below the input field.

Number of planes

XX Enter the number of plane measurements. The default setting is
30 planes.
Specifying the number of plane measurements, you determine thenumber of measuring points that are displayed in the coordinates of
the Beam Pointing Stability tool. To determine a measuring point, thebeam cross sections are measured once at the positions z1 and z2. If,
for example, 10 measuring points are to be displayed, enter the valueof 20.

Tab. 12.10: Options in the Device control > Settings tab of the Beam pointing measuring mode

Revision 00 EN – 06/2021

79

35,0(6

MicroSpotMonitor MSM+

OptionExplanation

z-Axis position (z1 / z2)

The measuring positions z1 and z2 determined during the pre-caustic
measurement are displayed here.

Tab. 12.10: Options in the Device control > Settings tab of the Beam pointing measuring mode

12.9.3

Configuring advanced settings

1.

Click on the Advanced tab.

2.

Maintain the options according to the
explanations in Tab. 12.11.

OptionExplanation

Save device settings

All options marked with an asterisk in the Device control menu can besaved in the EEPROM of the device.
These and other options for saving / loading configurations are described in chapter 12.4.4 on page 45.

# Pixel in x/y *This option enables setting the resolution of the CCD sensor:
XX Enter the number of pixels in the x-direction / y-direction in the input
field on the left / right.

Low power mode

We recommend enabling this option for low power laser beams (< 1 W).
If this option is enabled, the following initial values are selected during
beam search• Filter level of the filter wheel (if available): 0 (instead of 1 otherwise)• Integration time: 10 ms (instead of 1 ms otherwise).
XX Set the check mark to enable the option.

Locked area

Locked area means a restriction of the traversing range in the z-direction. The lower limit of the enabled traversing range is always home
position. The upper limit can be set freely.

Maximum z-Position in mm *1. Use one of the following options to set the locked area:
XX Enter the upper limit of the permitted z-traversing range in the input
field.
XX Use the slider below the input field.
We recommend saving a locked area in the device, if it is safety-relevant:
2. If you want to save the locked area (and the other options marked
with an asterisk) in the device, click the Save device settings button.
xx The settings are retained even if the device is switched off or disconnected from the power source.

Tab. 12.11: Options in the Device control > Advanced tab of the Beam pointing measuring mode

80

Revision 00 EN – 06/2021

MicroSpotMonitor MSM+

12.9.435,0(6

Measuring beam pointing stability

DANGER
Serious eye or skin injury due to laser radiation
X Observe the warning messages in chapter 12.1 on page 37.
Starting measurement1.

Switch on the laser.

2. Click the Start button.
xx The measurement begins.
During the measurement, the progress is shown in the following indicators:

Pre-caustic
While the indicator is rotating, the z1 andz2 positions along the beam propagation
are identified. The positions are optimized
according to Primes quality criteria.
After successful pre-caustic measurement, the indicator lights up green.
The process is visualized in the Falsecolor Image tool.

Measuring beam pointing
While the indicator is rotating, the beam's
centers of gravity are constantly recordedat the positions z1 and z2.
The determined measuring points
are displayed in the coordinates of
the Beam Pointing Stability tool.
The current position of the beam ismarked with a large X, previous positions are marked with a small x.

Revision 00 EN – 06/2021

81

35,0(6

MicroSpotMonitor MSM+

Completing measurement
When the beam pointing measurement is completed, the indicator
Beam Pointing changes to green.
1.

Click on the Stop button.

2.

Switch off the laser.

You can reset the values for beam position
stability in the Position and Angle windows by pressing the Reset button.
You can log the Beam pointing stability
as described in chapter 12.9.5 on page
83.

82

Revision 00 EN – 06/2021

MicroSpotMonitor MSM+

12.9.535,0(6

Logging beam pointing stability

You can log the beam pointing stability
under Device control > Settings:
1.

Enter the value of 0 in the Number ofplanes field.

2.

Click on the Projects tab.

3. Click on the Start button.
xx Continuous measurement data forbeam position stability is generated in
the project tree.
4.

Click on the Stop button.

5.

Click on the Save icon in order tosave the measurement data.

The measuring points in the Position and Angle windows can be deleted by clicking the gear icon
Reset button.

and the

The measured data in the project tree is not deleted in the process.

Revision 00 EN – 06/2021

83

35,0(613

MicroSpotMonitor MSM+

Troubleshooting

Error

Possible cause

RemedyThere is no connection between
the device and the PC.

The Network address of the
PC is not within the range ofthe device.

In Windows > Control panel > Network andSharing Center, assign an IP address to your PCthat is in the same address range as the device.

The connection may beblocked by the firewall.

Enable the UDP port 20034 according to chapter 12.2.2 on page 40.

An incorrect network interface card is selected.

Select the appropriate network interface card according to chapter 12.2.2 on page 40.

•
•

1.
2.

Error during a measurement•
Apart from the ambient noise andzero offset, no measuring signal
is available.

Data transmission error
Processor crash in themeasuring system
Program execution error

3.

Restart the software.
Switch off the supply voltage, switch it on
again, and start another reset cycle.
Restart the computer.

The laser is not switched on.

Switch on the laser.

The device is not aligned
correctly.

Check the device alignment to the laser beam.

The power density in thefocus is too low.

Try the following actions in the order given:
1. Enlarge the measurement window.
2. Increase the integration time or select aweaker filter of the filter wheel (if available).
3. Increase the laser power (step by step).

The safety interlock has been
triggered.

The cover of the inspection
chamber is not closed.

Close the cover.

Error messages in
LaserDiagnosticsSoftware LDS

Possible cause

RemedyAttention, the housing is open!

The cover of the inspection
chamber is not closed.

Close the cover.

Measurement is not possible
because no measuring objective
has been detected.

The measuring objective is
not / not correctly inserted.

Insert a measuring objective or check the position of the measuring objective.

The measuring objective used is
not calibrated for this device, themeasurement inaccuracy may besignificantly increased.

A measuring objective froma different device may havebeen inserted.

Check the inserted measuring objective.
PRIMES should calibrate the measuring objective
for higher accuracy.

Measurement can’t be taken,
the connection with the camera
head has been disrupted. Pleaseswitch the device off and on
again.

The device wasn’t able toinitialize the camera head.

Switch the device off and on again.

Error in saving the user-defined
device settings, the parametersmust be reset.

It wasn’t possible to save thedevice settings in the device.

Save the device settings again.

Internal device error. Switch thedevice off and on again. Device
moves to the home position during this process.

The device is experiencing
an internal error.

Switch the device off and on again.

84

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

14Maintenance and service

14.1

Maintenance intervals

The operator is responsible for determining the maintenance intervals for the measuring device. PRIMES
recommends a maintenance interval of 12 months for inspection and validation. If the device is used only
sporadically, the maintenance interval can also be extended up to 24 months.

14.2

Cleaning

You can remove light contamination with compressed air. Make sure that all device openings are closed.
For further cleaning, PRIMES recommends a mixture of distilled water and isopropanol in a ratio of approx.
5:1. Use lint-free cleaning cloths that do not scratch. This can be e.g. microfiber cloths or paper towels fromthe cosmetics sector.
If these measures are not sufficient, please contact PRIMES.

14.3

Exchanging the protective window

The measuring objective can optionally be delivered with a protective window or a combination of protective
window and cyclone. The protective window in the beam entrance is a wearing part and can be replaced if
necessary. Low levels of contamination of the protective window can be carefully removed with Isopropanol
when it has cooled down (observe the manufacturer‘s safety instructions). In case of heavy, non-removable
contamination or damage, the protective window must be replaced with a new one.
The protective window is coated with an antireflex coating and has low reflection values of less than
1 %. To avoid increased reflection values, use only original PRIMES protective windows.
Order number

Suitable for the following spectra:

DiameterThickness

NIR

VIS

UV

801-004-054



—

—

30 mm

1.5 mm801-004-068





—

30 mm

1.5 mm801-004-069







30 mm

1.5 mm

14.3.1

Warning messages

DANGER
Severe eye or skin injury due to laser radiation
If the protective window is not correctly positioned, reflections can cause directional laser
radiation.
X Make sure that the new protective window is settled flat in the groove of the protective window mount.

CAUTION
Burns due to hot components
After a measurement the protective window is hot!
X Do not replace the protective window directly after a measurement.
X Let the device cool down for an adequate period of time. The cooling time varies dependingon the laser power and the irradiation time.

Revision 00 EN – 06/2021

85

35,0(6

MicroSpotMonitor MSM+NOTICE
Damaging / destroying the device
Contamination and fingerprints on the protective window can lead to damage or shatteringor splintering of the protective window.
X Only replace the protective window in a dust-free environment.
X Do not touch the protective window.
X When exchanging the protective window wear suitable gloves.
The protective window is located in the protective window mount of the measuring objective below the retaining ring / cyclone. The retaining ring / cyclone is attached to the protective window using a spring-loaded
bayonet lock with three locking pegs.
14.3.2

Replacing the protective window

1. Observe the warning messages in chapter “14.3.1 Warning messages” on page 85.
2. Push the retaining ring down against the protective window mount, turn it counterclockwise until it stops
and lift the retaining ring up and off.
3. Remove the old protective window from the protective window mount (for example with a suction cup)and dispose of it.
4. Carefully place the new protective window into the protective window mount.
5. Position the locking pegs of the retaining ring in the openings of the bayonet lock.
6. Push the retaining ring down and turn it clockwise until it stops.
xx The bayonet lock is locked.

Retaining ring
Protective window

Protective window mountFig. 14.1:

86

Components of the protective window mount

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

14.3.3Replacing the protective window for cyclone

1. Observe the warning messages in chapter “14.3.1 Warning messages” on page 85.
2. Remove the compressed air hoses around the cyclone if necessary.
3. Push the cyclone down against the protective window mount, turn it counterclockwise until it stops andlift it up and off.
4. Remove the old protective window from the protective window mount (for example with a piece of adhesive tape) and dispose of it.
5. Carefully place the new protective window into the protective window mount.
6. Position the locking pegs of the cyclone in the openings of the bayonet lock.
7. Push the cyclone down and turn it clockwise until it stops.
xx The bayonet lock is locked.

CycloneCompressed air connections

Protective window

Protective window mountFig. 14.2:

15

Components of the protective window mount with cyclone

Measures for the product disposal

PRIMES gives you the opportunity to return your PRIMES measuring device for free disposal within thescope of the Waste of Electrical and Electronic Equipment (WEEE Directive). This service does not include
shipping costs. You can send PRIMES measuring devices to be disposed of within the EU to our address:
PRIMES GmbH
Max-Planck-Str. 264319 Pfungstadt
Germany
If you are located outside the EU: please contact your local PRIMES distributor to discuss the disposal procedure.
PRIMES is a registered manufacturer in the German “Used Appliances Register“ stiftung elektro-altgeräte
register (stiftung ear) with the number WEEE-reg.-no. DE65549202.

Revision 00 EN – 06/2021

87

35,0(61688

MicroSpotMonitor MSM+

Declarations of conformity

Revision 00 EN – 06/2021

MicroSpotMonitor MSM+

Revision 00 EN – 06/2021

35,0(689

35,0(617

MicroSpotMonitor MSM+

Technical data

Measurement parameters
Power range

1 mW – 200 W (optional 500 W with water cooling)

Wavelength range

257 – 272 nm (on request)
340 – 360 nm
515 – 545 nm
1 030 – 1 090 nm

Beam diameter

10 – 1 000 µm

Determined parameters
Focus position x, y, z

yes

Focus radius x, yyesBeam quality factor M²

yes

Raw beam diameter with focussing element

yes

Beam parameter product BPP

yes

Divergence angle

yesPower density distribution

2D, 3D

Device parameters
Traversing range x-y plane2 × 2 mm

Traversing range z-axis

35 mm (MSM+ 35), 120 mm (MSM+ 120)

Measurement window sizes

0.02 – approx. 3.5 mm(depending on the measuring objective)

Integrated variable attenuation (option)

Filter wheel with 5 OD filter (OD 0 – 5)

Supply data
Power supply

24 V DC ± 5 %, max. 1.8 A

Compressed air for cyclone (cleaned, free of water and oil)

0.5 – 1 bar

Specification of compressed air for the cyclone according to ISO 8573-1: 2010

6:4:4

Cooling water pressure (500 W device version only)

2  bar primary pressure with an unpressurized outflow,
max. 4  bar

Min. Cooling water flow rate
(500 W device version only)

1.5 l/minCooling water temperature Tin1)(500 W device version only)

Dew point temperatur < Tin < 30 °C

1)Please consult with PRIMES before working beyond this specification.

Communication
Interface

Ethernet

Dimensions and weight
Dimensions (L x W x H)

Length: 427 mm +12 mm traversing range + connector
Width: 202 mm
Height: 181 mm + 35 / 120 mm traversing range + projection depending of the measuring objective used

Weight15 kg

90

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

Environmental conditions
Operating temperature range

10 – 40 °C

Storage temperature range

5 – 50 °C

Reference temperature

22 °C

Permissible relative humidity (non-condensing)

10 – 80 %Dimensions

180.2 +35/+120
219 +35/+120

18427 +12

157.5
166.6

187.5
2x Ø112x Ø6.6

4x Ø6.6

53.5 ±5
21

202

160
194.8

150

316.6 +12

All dimensions in mm

Revision 00 EN – 06/2021

91

35,0(6

MicroSpotMonitor MSM+

19

Appendix

19.1

Insert fixed OD filter (option) in the inspection chamber

1. Switch off the laser source.
2. Ensure that moving parts, for example robot arms, etc. are at a standstill and that they cannot be set inmotion unintentionally.
3. Switch off the device.

NOTICE
Damaging / destroying the optical components
Contamination can damage or destroy the optical components.
X Only open the inspection chamber in a dust-free environment.
4. Unscrew the knurled screw on the cover and open the cover.
5. Insert the fixed filter into the slot provided.
The insert has different guides so that the fixed OD filter can only be inserted in one position.
6. Close the cover and screw in the knurled screw.
7. Check the secure fit of the cover:
The cover must fit flush with the housing, so that no dust or dirt can get into the inspection chamber.
Knurled screw

Fig. 19.1:

92

Cover closed

Fixed OD filter

Cover opened

Insert fixed OD filter into the inspection chamber

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

19.2

Optical components

The device is a camera-based measuring system. Depending on the application, up to 7 different opticalcomponents can be placed within the beam path. The purpose and functionality of individual components
are described in the following chapters.
Laser beam
Upper limit
Measuring
plane

Permissible measuring range

Lower limit

Measuringobjective
AbsorberPrismsFixed OD-filter (option)

Mirrors

Field objective (FO)CCD sensor
Absorber

Trigger
Filter wheel (option)
Beam path extension (BPE)

Fig. 19.2:

Example of the optical design of the device

Revision 00 EN – 06/2021

93

35,0(619.2.1

MicroSpotMonitor MSM+

NA limit value, typical magnification and measuring plane distance

The interaction of the optical components makes it possible to image a measuring plane perpendicular to thez-axis and outside the measuring device onto the CCD sensor inside the device. Three important quantities
must be considered in connection with this (see Tab. 19.1): the numerical aperture limit (NA limit), the typicalmagnification and the measuring plane distance.
The measuring plane distance is the distance between the measuring objective and the measuring plane.
The values listed in Tab. 19.1 correspond to the distance from the measuring plane to the upper edge of themeasuring objective. The measuring plane distance is essential for the manual alignment of the device along
the z-axis (see 8.3.1 on page 23).
Measuringobjective

NA limit
values3.3x
1 064 nm
532 nm355 nmTyp. magnification

Measuring plane distance in mm

Standard

with BPE

with FO

Standard

with BPE

with FO

0.11
0.1
0.09

3.12
3.23
3.36

5.65
5.81
6.02

1.12
1.11
*)

73
70.5
67.3

64.6
62.6
60.1

63.7
61.5
57.7

1 064 nm
532 nm355 nm

0.19
0.18
0.14

4.96
5.15
5.35

8.31
8.6
8.92

1.63
1.59
*)

51.1
49.3
47.2

47.1
45.7
43.8

46.7
45.1
42.7

10x
1 064 nm
532 nm355 nm

0.24
0.24
0.15

8.84
9.17
9.62

14.39
14.91
15.6

2.77
2.72
*)

29.9
-

27.9
-

27.6
-

5x

Tab. 19.1:

NA limit value, typical magnification and measuring plane distance*) Only suitable for adjustment
FO = field objektive
BPE = beam path extension
If a 1.5 mm thick protective window is used, the measuring plane distance increases by approx.
500 µm.
Due to manufacturing tolerances, the values of the measuring plane distance listed in Tab. 8.1 aresubject to an error of ± 800 µm. However, it is possible to validate the measuring plane distance ofthe measuring objectives to an accuracy of ± 50 µm (TCP determination).

94

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

19.2.2

Measuring objective

The measuring objective is a lens system designed to image a measuring plane perpendicular to the z-axis
and outside the measuring device onto the CCD sensor inside the device.
This non-contact measurement offers the advantage that even very high power densities can be detected.
The measuring objective makes it possible to enlarge the beam and thus to image a sufficient resolution on
the CCD sensor.
Fig. 19.3 shows a diagram of the measuring objective. It includes all important parameters.
Main planes
H

Object planesH‘f

Picture plane
y

x

a
a‘
Optical axis
Measuring plane distanceFig. 19.3:

Illustration of a defined measuring plane with a measuring objective

The main planes H and H‘ in the measuring objective or image space are auxiliary quantities in order tocombine any number of optical components into one unit. The focal length f, offset distance a, and image
distance a‘ are measured from the intersection of the main planes with the optical axis (cardinal point).
The dimensions x, y and the measuring plane distance are important auxiliary quantities. They establish therelationship between the optics and the socket edge.
The projection of the measuring objective is calculated according to the following formula:(1.1)

The focal length f is dependent on the wavelength and, as a result, the image distance a’ is dependent on
the object distance a.
The magnification of the measuring lens is calculated from the quotient of a and a’:(1.2)

The combination of the two formulas gives β a dependence on the image size a’ and the focal length f. The
focal length is determined by selecting a measuring objective and the image distance is determined by theconstruction of the measuring device.

Revision 00 EN – 06/2021

95

35,0(6

MicroSpotMonitor MSM+

The choice of the measuring objective depends on the geometry and the beam parameters of the laser
beam to be measured. The sensor area of the CCD sensor is 4.76 mm x 5.58 mm.
According to ISO 11146, the measurement must be carried out for at least 4, more preferably 6 rayleighlengths.
According to the following formula the sensor area must be at least 5 times larger than the expected focus
diameter.

ωσ(z) = ωa0(1.3)

Once the appropriate measuring objective has been selected, the MicroSpotMonitor MSM recognizes theassembled measuring objective via an electronic coding on the holder of the measuring objective and adjusts
the available measuring windows.
If, for example, the maximum square measurement window size in a 1:1 figure on the CCD sensor 4 mm x
4 mm, it should be reduced to 0.4 mm x 0.4 mm at a magnification of 10:1.
The inlet aperture of the device can easily be aligned with the optical axis of the laser beam within a range of2 mm x 2 mm using an alignment tool (see chapter 8.3.3 on page 25). The path of movement of the x andy axis of 2 mm makes it possible to position the laser beam precisely on the CCD sensor.

Measuringobjective 10:1

2 mm

Magnification 1:10

4.76 mm = 1024 pixels

Pixel

2 mm

CCD sensor field
Fig. 19.4:

5.58 mm = 1360 pixels

Schematic illustration of a measuring plane on the CCD sensor

Fig. 19.4 shows schematically the projection of a measuring plane onto the CCD sensor. The reticule on theleft shows the measuring area, which can be measured with the integrated x- / y-axis. This can also be done
automatically.
Within the measuring area, a measuring window can be positioned (size depending on measuring objective).
On the right, the CCD sensor field is displayed. The measuring window, which has an edge length of 0.4 mm(in the object level), is projected to the chip with a 10-fold magnification.
Equation (1.1) shows that the farther the focus is from the measuring lens (afokus), the shorter it is imaged
behind the measuring lens (a´fokus). Therefore, it is necessary to align the beam focus within a permissible
range on the z-axis. Detailed information on this can be found in chapter 8.3, „Manually aligning the device“,
on page 23.

96

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

19.2.3

PrismsAfter the measuring objective, the laser beam hits three uncoated quartz glass prisms which attenuate thelaser beam.

z
Fixed OD flter(option)x

Measuringobjektive
Prismsx

Fig. 19.5:

Section of the beam path of the device

The reflection is described with the Fresnel formulas. They describe the so-called reflection respectivelytransmission ratio of light at surface boundaries.

(1.4): Reflection ratio of vertically polarized light.

(1.5): Transmission ratio of vertically polarized light.

(1.6): Reflection ratio for parallel polarized light.

(1.7)

Revision 00 EN – 06/2021

97

35,0(6

MicroSpotMonitor MSM+

: Transmission ratio of parallel polarized light.

(1.8)
n1: Medium 1
n2: Medium 2
Fig. 19.6:

Reflection of a beam at surface boundaries

The reflection respectively the translucence coefficients correspond to the squares of the respective ratios.
(1.9)

Reflection in %Plotted on a graph, the following curves are obtained:

Incidence angle in degree
Fig. 19.7:

Reflection of a laser beam at the prisms in % as a function of the angle of incidence

The curves in Fig. 19.7 were calculated for a wavelength of 1 064 nm. The refractive index n of quartz glass
is wavelength-dependent. It varies from 1.4498 to 1.4766 in the wavelength range of 350 to 1 064 nm.
It can be clearly seen that the reflection characteristics depend on polarization. This also applies to an angle
of incidence of 45°, the angle of incidence at which the beam passes through the device.
For this reason, the prisms are integrated in the device in such a way that the beam is diverted in all threespatial directions (see Fig. 19.5 on page 97). This ensures that always two of the three incidence planes ofthe prisms are perpendicular to each other and compensate the polarization effects.

98

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

Nevertheless, the attenuation of the prisms remains a function of the wavelength and polarization of the laserbeam.
In the optimal case for reflection,• the laser beam is attenuated by a factor of 1.7 · 10-4 (λ = 350 nm; polarized),• in the worst case by the factor of 6 · 10-5 (λ = 1064 nm; || polarized).
For all other wavelengths (between 350 nm and 1 064 nm) and polarizations, the values are in between.
However, this only affects the measurements if the polarization changes over the beam profile. In this case,an additional prism can be mounted above the measuring objective. The radiation transmitted by the prisms
is guided via mirrors to the absorber resp. to a trigger diode.
19.2.4

Fixed filter and filter wheel

For further attenuation of the beam, an arbitrary fixed OD filter (option) can be inserted into the beam path(see chapter 19.1 on page 92). Behind the retractable OD filter is a filter wheel (option). The filter wheel
has 6 positions. It can be operated during the measurement via software control. The filter wheel is equippedwith five filters with an optical density between 1 and 5. The 6th position remains empty in order to allow thelaser beam to pass unfiltered.
Neutral‑density filters have approximately the same transmittance over a wide wavelength range. The degreeof weakening can be varied with the type of glass and the thickness of the filter.
However, the filters are only capable of handling 100 mW/cm², that‘s why they are not suitable to substitutethe prisms.
The maximum average power for the wavelength range 1030 nm to 1090 nm (NIR) is 200 W (500 W forwater-cooled device versions). Be sure to use the aperture of the measuring objective when operating in thispower range.
The formula for converting the optical density into the transmission coefficient in % is:(1.10)

Transmission in %The Filter wheel can be selected to weaken the laser beam by a factor of 10 to 105. Taking both filter levels
together results in a dynamic range of 200 dB.

Wavelength in nm
Fig. 19.8:

Typical transmission curve of a neutral‑density filter

Revision 00 EN – 06/2021

99

35,0(619.2.5MicroSpotMonitor MSM+

Beam path extension (BPE)The beam path extension allows the user to adjust the overall magnification of the system.

Beam path extension

Fig. 19.9:

Beam path extension of the device

The beam path extension consists of four mirrors. Using the levers to adjust the magnification (see Fig. 4.1
on page 11), it can be inserted in the beam path directly behind the filter wheel.
According to equation (1.1) for the measuring objective, this results in an enlargement of the overall image.
The factor by which the magnification changes depends on the measuring objective and is approximately
1.5.
Note that the use of the beam path extension also changes the measuring plane distance. Therefore, the alignment of the device on the z-axis must be readjusted after activating / deactivating thebeam path extension (see chapter 8.3, „Manually aligning the device“, on page 23).
19.2.6

Field objektive (FO)The field objective can be inserted into the beam path on the image side. Depending on the wavelength andthe measuring objective used, this results in a reduction of the image by a factor of 2 to 3. This lens is particularly suitable for adjustment, because the device must be positioned less precisely to the laser beam dueto the reduced imaging.
The reduced imaging of the measurement plane can also be seen as an enlargement of the active area of thecamera chip. The sensor area of the CCD sensor is 4.76 mm x 5.58 mm. Using a 10x measuring objectivemeans that in the standard case the device has to be positioned to approx. 0.5 mm in the x- / y-direction, forexample in CCD mode. With the help of the field objecive, this range can be extended to 1.5 mm.
The adjustment lens can be validated at wavelengths of 1064 nm and 532 nm. At the wavelengthof 355 nm, it can only be used for alignment.
Note that the use of the field objecive also changes the measuring plane distance. Therefore, thealignment of the device on the z-axis must be readjusted after activating / deactivating the fieldobjecive (see chapter 8.3, „Manually aligning the device“, on page 23).

100

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

19.2.7

AbsorberMore than 99.8 % of the transmitted beam power is redirected by the first two prisms through a mirror system to an absorber.
The absorber is a channel in which the beam is completely absorbed by multiple reflections. The maximum
average power for the wavelength range 1030 nm to 1090 nm (NIR) is 200 W (500 W for water-cooled device versions).
19.2.8Trigger diodeWith the aid of a sensor, the transmitted beam of the third prism is used as a triggering signal. The threshold at which the sensor sends a triggering signal can be set by the user or automatically. This signal can beused by the software to control delay and exposure time as well as better measure pulsed laser beams (seechapter 19.3).

19.3

Measuring pulsed irradiation

19.3.1

Trigger operation

The dynamic range of the CCD sensor in the camera housing is extended by means of a variable integration
time control. The integration time can be freely determined in the range between 6 µs and 225 ms, or it canbe set automatically (for this purpose, activate the Autom. exposure option in the Settings tab of the Single
planes measuring mode, see chapter 12.5.2 on page 52).
If the automatic exposure is enabled, then the software will automatically – using a series of pre-measurements – set the integration time at which the output signal of a pixel in the array is too high. The optimal
integration time will then be a little below that.
By means of the variable integration time control, not only cw laser beams but also a multitude of pulsed
beams can be measured in quasi-cw operation. An exception are, for example, laser beams with a very
low pulse frequency.For measuring such beams, the trigger operation is available in the measuring modes
Single planes / Manual caustic / Automatic caustic (see chapter 12.5 on page 51 / chapter on page
66 / chapter 12.8 on page 73). If this is enabled, the device only measures within defined time periods.
The laser pulse or the corresponding trigger signal marks the beginning of such a period and the (freely adjustable) integration time marks its end.
Fig. 19.10 shows that in addition to the trigger signal and the integration time, a further variable intervenes inthe sequential control of the CCD sensor: the trigger delay. It indicates the time period between the trigger
signal and the start of the integration time.

Trigger

Delay time

Sequential -control camera

Triggerlevel
Fig. 19.10:

Integration time

Options for affecting the sequence control of the CCD sensor

A measurement can be triggered internally or externally. Internal signals are triggered by the photodiode integrated in the device. Externally triggered signals enter the device via a BNC socket. You can freely determine
the threshold value of the internal trigger signal (trigger level).

Revision 00 EN – 06/2021

101

35,0(6

MicroSpotMonitor MSM+

Every measurement consists of a dark measurement and a measurement with photo transfer. This applies
for trigger operation as well as cw / quasi-cw operation. This means that each measurement requires at least
two trigger signals.
The following time constants apply:
Timeout:		
Minimum integration time:
Maximum integration time:
Minimum delay: 			
Maximum delay: 		
19.3.2

2 sec (Standard)
6 µs
225 ms12 µs
400 msMeasuring configuration selection

There are various measuring options to differentiate between:
•
•
•
•
•

Measuring a single plane or a caustic
Measuring a complete pulse or just a single section
Measuring with freely adjustable integration time or with automatic integration time control
Measuring in trigger operation or quasi-cw operation
Variations of optimal integration time caused by changing the attenuation

Combining these measurement options with the following pulse parameters provides numerous possibilities:••

Pulse duration: fs – ms
Pulse frequency: 1 Hz – 1 kHz

The following merely describes a rough structure that is intended to help in choosing measuring settings.
19.3.3

Influence of the pulse parameters on the integration time control

The software-operated integration time control always assumes that there is a cw laser beam.
This may cause quantization of the integration time for slow pulse lasers (< 500 Hz) or lasers with high pulse
energy (integration time very short). Tab. 19.2 And the diagram in Fig. 19.11 on page 103 illustrates this.
Pulse frequency

Number of detected pulses

in Hz

at maximum integration time 225 ms

at integration time 1 ms

1

0

0–1

5

1

0–1

10

2

0–1

50

11

0–1

100

22

0–1

200

45

0–1

500

112

0–1

1 000

225

1–2

2 000

450

2–3

5 000

1 125

5.00

10 000

2 250

10.00

Tab. 19.2:

102

Number of detected pulses in correlation with the integration time and pulse frequency

Revision 00 EN – 06/2021

35,0(6Percent change in energy for
n-1 pulses

MicroSpotMonitor MSM+

Pulse frequency in Hz
Fig. 19.11:

Percentage of change in the detected energy when exactly one pulse is left out, in correlation with the pulse
frequency

Tab. 19.2 shows the number of detected pulses during the maximum integration time and during an integration time of 1 ms for different pulse frequencies. Quantization with low pulse frequencies is clearly illustrated
in the column for the maximum integration time. While 2 250 pulses are detected at a pulse frequency of
10 kHz, at 10 Hz there is only one or no more than two.
If the signal level is too high during a measurement at 10 Hz pulse frequency and the software tries to adjust
the integration time, there are only three possible results. The energy application for a measurement remains
the same, it decreases by 50 %, or it drops to zero. These increments are less significant at a pulse frequency of 10 kHz. This correlation is shown in general terms in Fig. 19.11 on page 103. It can be seen that froma pulse frequency of 500 Hz, the minimum jump with a reduction of the integration time is 1 %.
Small pulse frequencies aren’t the only thing that will cause quantization though. If the pulse energy is very
high and it isn’t possible to further increase the attenuation, the integration times will be smaller. In Tab. 19.2,
an integration time of 1 ms is added to the maximum integration time. In this case, a pulse frequency of
500 Hz is not sufficient in order to quasi continuously control the energy application for each measurement
through integration time control.
A total of four states can always be differentiated on the way from low to high pulse frequencies or from short
to long integration times. This is demonstrated by the following example for measuring pulsed irradiation during quasi-cw operation.

Revision 00 EN – 06/2021

103

35,0(6

MicroSpotMonitor MSM+

I in W/cm²∆t in μs
Fig. 19.12:






t in μs

Measuring with different integration times

12 – 200 µs:
200 – 400 µs:
200 – 2 ms:
2 – 200 ms:

Sporadic measuring of pulses
1 pulseQuantization noise cause by a varied number of pulses
Virtually continual integration time control

Fig. 19.12 shows pulsed irradiation. The pulse pauses are 200 µs. The required integration time of the sensor
correlates directly with the intensity of the laser beam.
If it is smaller than the pulse pause as in case 1, statistically there is a maximum of 1 pulse in the measurement. The probability that a pulse is present during each measurement for integration time control as well as
during the actual measurement is low.
If the optimal integration time falls exactly between the simple and double duration of the pulse pause, there
will always be just one pulse in each measurement (case 2). This is the perfect state for measuring on one
plane. The caustic can also be measured with this setup. Here it is important to make sure that the signal
saturation for the measurement in the focus is as high as possible. Only then is it possible to ensure that
there is a sufficient S/N ratio when measuring a plane far outside of the focus.
Case 3 describes the case in which the integration time ranges between the single and tenfold duration of
the pulse pause. Within this range, every pulse is more or less noticeable as a clear signal jump during the
integration time. Integration time control is only possible with quantization. The measuring results often havea bad S/N ratio or the signal level is too high.
If the integration time increases even more, the signal jumps become flatter. Integration time control operates
quasi continuously (case 4). The laser being measured can now be measured as a cw laser.
The neutral-density filters, which can be inserted into the optical path, make it possible to always work within
the desired range 1 to 4.
In addition, trigger operation is available for the device. Together with the integration time control and a delay
time control, measurements can also be made reliably in case 1.
These four cases can generally be sorted into two groups. Case 1 and 2 must be measured in trigger operation. Case 4, however, is best measured in quasi-cw operation. Case 3 should be avoided altogether bychoosing a suitable filter.
The diagram in Fig. 19.13 shows a classification of laser beams to be measured with regard to the suitable
operation mode.

104

Revision 00 EN – 06/2021

35,0(6

MicroSpotMonitor MSM+

Pulse frequency
1 MHz
100 kHzcw operation

10 kHz
1 kHz

Quasi-cw operation

100 HzTrigger operation

10 Hz
1 Hz
1 μs
Fig. 19.13:

10 μs

100 μs

1s

10 s

100 s

Pulse duration

Selection of the appropriate measurement mode based on laser parameters

For the blue field laser beams, the quasi-cw operation is most suitable. However, be aware that as thepulse frequency decreases, the required integration time increases to ensure the quasi-cw case. As a ruleof thumb, the integration time of a focal plane measurement should be approximately the same as the timefor 35 pulses. If the laser beam to be measured falls below a pulse frequency of approx. 500 Hz, you shouldswitch to trigger operation.
While it is almost always possible to measure with the integration time control in the cw or quasi-cw operation, it only makes sense to use it for very long pulse durations (>1 ms) in trigger operation. With the helpof the attenuation filters, the integration time is adjusted in such a way that it is only a fraction of the pulse
duration. The trigger signal will then merely specify to the device the starting time for the measurement. The
integration time may increase or decrease during the course of the caustic measurement without leaving thepulse path (see Fig. 19.14 and “Example 2: very long pulse duration” on page 106).
P Lasermin Delay (12 μs)
Fig. 19.14:

tp – 1 ms

Integrationszeit
Integration
time (e. g. 100 μs)t

Measuring parameters for pulsed laser systems with pulse duration greater than 1 ms

For all other cases, it is advisable to specify a fixed integration time in order to always measure a fixed number of pulses by cleverly selecting the filters and the delay and integration time (“Example 1: fixed integrationtime” on page 106).

Revision 00 EN – 06/2021

105

35,0(619.3.4MicroSpotMonitor MSM+

Examples for trigger operation

Example 1: fixed integration time
With these settings, the device detects the second laser pulse after the trigger is released. Depending on
how precisely it can be triggered, the integration time can also be varied.
Laser parameter

Device settings

Pulse duration:

50 ns

Delay:

950 µsPulse frequency:

1 kHz

Integration time:

100 µsTrigger channel:

external trigger signal

Example 2: very long pulse duration
In this example, the first 12 µs of the laser pulse are not measured.
Laser parameter
Pulse duration:

19.3.5

Device settings
1 ms

Delay:

12 µs

Integration time:

1 ms

Trigger channel:

internal trigger signal

Summary

If the laser is pulsing at a high frequency (> 500 Hz) or if the pulses last a long time (> 1ms), it is best to measure with the automatic integration time control. This makes it possible to vary or optimize the integration
time during a caustic measurement.
For the long pulse duration, choose the attenuation so that the integration time is smaller than the pulse
duration even outside of the focal point.
When the pulse frequency is very high, however, the attenuation must be chosen so that enough laser pulses
are integrated during the measuring cycle. If too few pulses occur during an integration time, the number ofphotoelectrons will change too much with each pulse. The regulating routines of the LaserDiagnosticsSoftware LDS will then lead to measurements with signal levels that are statistically too high.
It is important to make sure that the integration time is never shorter than the pulse pauses. If this is thecase, it will no longer be possible to perform an untriggered measurement properly with the device.
So it sometimes makes sense to set the attenuation so that exactly one pulse is enough to expose the sensor at the focal point. You can then measure a caustic with a fixed delay and an integration time set when
the focus was measured. The dynamic of the CCD sensor is sufficient to measure the entire caustic with anacceptable S/N ratio.

106

Revision 00 EN – 06/2021