THORLABS PM300 User manual

Operation Manual
Thorlabs Instrumentation
Optical Power Meter
PM300
2007

Version: 13515-D02 REV A
Date: 18.04.2007
Copyright©2007, Thorlabs, Germany

Contents page
1General Information 5
1.1 Safety 6
1.2 Ordering Codes and Accessories 9
2Getting Started 10
2.1 Unpacking 10
2.2 Preparation 10
2.3 Physical Overview 11
2.3.1 Operating Elements at the Front Panel 11
2.3.2 Operating Elements at the Rear Panel 12
2.3.3 Main Screens 13
3Operating the PM300 14
3.1 Sensor independent Operation and Settings 14
3.1.1 Navigating the Menus 14
3.1.2 System Settings 14
3.1.3 Readout Configuration 15
3.1.4 Range Setting 15
3.1.5 Relative Power Measurement 16
3.1.6 Setting an Attenuation Factor 17
3.2 Operation with a Photodiode Sensor 17
3.2.1 Wavelength Correction 18
3.2.2 Dark Current Adjustment 19
3.2.3 Bandwidth Setting 20
3.3 Operation with a Thermal Sensor 21
3.3.1 Zeroing 21
3.3.2 Readout acceleration 22
3.3.3 Custom Thermal Elements 22
3.4 Operation with Photodiodes 22
3.4.1 Photodiode Polarity 23
3.4.2 Setting the Photodiode Responsivity 23
3.4.3 Bias 23
3.5 Analog Outputs 23
3.6 Miscellaneous Analog Output 24
3.7 Chart Mode 24
3.8 System Configuration 25
4Computer Interface 25
4.1 Connecting a Computer 25

2
4.2 PM300 Utility Software 26
4.3 Firmware Update 27
4.4 Command Reference 28
4.4.1 Common IEEE488.2 Commands 28
4.4.2 Measurement Commands 32
4.4.3 Device Setup Commands 34
4.4.4 Sensor Commands 44
4.4.5 MISC-Output Commands 46
4.4.6 Device Status Commands 50
4.4.7 General System Commands 52
5Measurement Considerations 55
5.1 Measurement of Pulsed Signals 55
5.2 Line-width of Light Sources 55
5.3 Temperature Effects on Thermal Sensors 55
5.4 Ambient and Stray Light 56
5.5 Backreflection 56
5.6 Fiber Based Measurements 56
6Maintenance and Repair 57
6.1 Maintenance 57
6.2 Line voltage setting 58
6.3 Replacing the mains fuses 59
6.4 Troubleshooting 61
7Appendix 65
7.1 Warranty 65
7.2 Certifications and compliances 66
7.3 Technical data 67
7.3.1 Common Data 67
7.3.2 Technical Data 67
7.4 Pin Assignment of the Sensor Connector 69
7.5 Thorlabs Power Sensors 70
7.5.1 S120B / S121B Silicon Sensor 70
7.5.2 S122B Germanium Sensor (PM122) 71
7.5.3 S130A / S132B Slim Sensor (PM130 / PM132) 72
7.5.4 S140A / S144A Integrating Sphere Sensor (PM140 / PM144) 73
7.5.5 S210A 3W Thermal Sensor 74
7.5.6 S212A 10W Thermal Sensor 75
7.5.7 S213A 30W Thermal Sensor 76
7.6 Selection of Thorlabs Photo-Diodes 77
7.6.1 SM05PD Series 77

3
7.6.2 SM1PD Series 77
7.6.3 IS200 Integrating Sphere Series 78
7.6.4 Calibrated Photodiodes 78
7.7 Thorlabs ‘End of Life” policy (WEEE) 79
7.7.1 Waste treatment on your own responsibility 79
7.7.2 Ecological background 80
7.8 List of figures 81
7.9 Addresses 82

4
We aim to develop and produce the best solution for your application in the
field of optical measurement technique. To help us to live up to your
expectations and develop our products permanently we need your ideas and
suggestions. Therefore, please let us know about possible criticism or ideas.
We and our international partners are looking forward to hearing from you.
Thorlabs
This part of the instruction manual contains every specific information on the PM300
optical power meter. A general description is followed by explanations of how to
operate the unit manually. You will also find information about a simple remote
control of the unit.
Attention
This manual contains ‘WARNINGS” and ‘ATTENTION” labels in this
form, to indicate danger for persons or possible damage to equip-
ment.
Please read these advises carefully!
NOTE
This manual also contains ‘NOTES” and ‘HINTS” written in this form.

1.1 Safety
5
1 General Information
The PM300 Benchtop Optical Power Meter is designed to measure the optical power
of laser light or other monochromatic or near monochromatic light sources.
The dual channel design and compatibility to all Thorlabs Photodiode and Thermal
power meter sensors and common Photodiode detectors, combined with a fast USB
device interface open a wide range of applications in Manufacturing, Quality Control,
Quality Assurance, and R&D.
The provided software, including drivers and applications for LabVIEW and C makes
it easy to integrate the instrument in test and measurement systems.

1.1 Safety
6
1.1 Safety
Attention 
All statements regarding safety of operation and technical data in this
instruction manual will only apply when the unit is operated correctly.
Before applying power to your PM300 system, make sure that the
protective conductor of the 3 conductor mains power cord is correctly
connected to the protective earth contact of the socket outlet!
Improper grounding can cause electric shock with damages to your
health or even death!
Also make sure that the line voltage setting of the fuse holder at the rear
panel agrees with your local supply and that the corresponding fuses
are inserted. If not, please change the line voltage setting (see section
6.2) and the mains fuses (see section 6.3).
The power meter PM300 must not be operated in explosion endangered
environments!
Sensor, photodiode and control inputs and outputs must only be
connected with duly shielded connection cables.
Only with written consent from Thorlabs may changes to single compo-
nents be carried out or components not supplied by Thorlabs be used.
Do not obstruct the air ventilation slots in housing!
Do not remove covers!
Refer servicing to qualified personal!
This precision device is only dispatchable if duly packed into the
complete original packaging including the plastic form parts. If neces-
sary, ask for a replacement package.

1.1 Safety
7
Attention 
Mobile telephones, cellular phones or other radio transmitters are
not to be used within the range of three meters of this unit since the
electromagnetic field intensity may then exceed the maximum
allowed disturbance values according to IEC 61326-1.
This product has been tested and found to comply with the limits
according to IEC 61326-1 for using connection cables shorter than 3
meters (9.8 feet).

1.1 Safety
8
Attention 
The following statement applies to the products covered in this
manual, unless otherwise specified herein. The statement for other
products will appear in the accompanying documentation.
Note: This equipment has been tested and found to comply with the
limits for a Class B digital device, pursuant to Part 15 of the FCC
Rules and meets all requirements of the Canadian Interference-
Causing Equipment Standard ICES-003 for digital apparatus. These
limits are designed to provide reasonable protection against harmful
interference in a residential installation. This equipment generates,
uses, and can radiate radio frequency energy and, if not installed and
used in accordance with the instructions, may cause harmful inter-
ference to radio communications. However, there is no guarantee
that interference will not occur in a particular installation. If this
equipment does cause harmful interference to radio or television
reception, which can be determined by turning the equipment off and
on, the user is encouraged to try to correct the interference by one or
more of the following measures:
▪Reorient or relocate the receiving antenna.
▪Increase the separation between the equipment and receiver.
▪Connect the equipment into an outlet on a circuit different from
that to which the receiver is connected.
▪Consult the dealer or an experienced radio/T.V. technician for help.
Thorlabs GmbH is not responsible for any radio television interfer-
ence caused by modifications of this equipment or the substitution
or attachment of connecting cables and equipment other than those
specified by Thorlabs GmbH. The correction of interference caused
by such unauthorized modification, substitution or attachment will
be the responsibility of the user.
The use of shielded I/O cables is required when connecting this
equipment to any and all optional peripheral or host devices. Failure
to do so may violate FCC and ICES rules.

1.2 Ordering Codes and Accessories
9
1.2 Ordering Codes and Accessories
Ordering code Short description
PM300 PM300 Dual Channel Benchtop Power Meter
PM320 PM300 + S120B Sensor; 400 – 1100nm; 50nW – 50mW
PM321 PM300 + S121B Sensor; 400 – 1100nm; 500nW – 500mW
PM322 PM300 + S122B Sensor; 700 – 1800nm; 50nW – 50mW
PM340 PM300 + S140A Sensor; 400 – 1100nm; 1µW – 1W
PM344 PM300 + S144A Sensor; 800 – 1700nm; 1µW – 1W
PM300-3 PM300 + S210B Sensor; 250 – 10600nm; 3W
PM300-10 PM300 + S212B Sensor; 250 – 10600nm; 10W
PM300-30 PM300 + S213B Sensor; 250 – 10600nm; 30W
S120B Si Photodiode Optical Sensor, 400 - 1100nm, 50nW-50mW
S121B Si Photodiode Optical Sensor, 400 - 1100nm, 500nW-500mW
S122B Ge Photodiode Optical Sensor, 700 - 1800nm, 35nW - 35mW
S130A Slim Sensor with Si Detector, 400 - 1100nm, 5nW to 500mW
S132A Slim Sensor with Ge Detector, 700 - 1800nm, 5nW to 500mW
S140A Integrating Sphere with Si Detector, 400 - 1100nm, 1mW to 1W
FC Adapter
S144A Integrating Sphere with InGaAs Detector, 800 - 1700nm, 1mW
to 1W FC Adapter
S210A 3W Thermal Sensor 250nm - 10.6µm
S212A 10W Thermal Sensor 250nm - 10.6µm
S213A 30W Thermal Sensor 250nm - 10.6µm
Please visit our homepage http://www.thorlabs.com for further information.

2.1 Unpacking
10
2 Getting Started
2.1 Unpacking
Inspect the shipping container for damage.
If the shipping container seems to be damaged, keep it until you have inspected the
contents and you have inspected the PM300 mechanically and electrically.
Verify that you have received the following items:
1. 1 PM300
2. 1 power cord, connector according to ordering country
3. Replacement mains fuses
4. 1 operation manual
5. 1 CD
6. (Sxxx power meter sensor when unit was shipped as a console - sensor set)
2.2 Preparation
Attention
Prior to switching on your PM300 please check if the line voltage set
with the voltage selector at the rear panel corresponds to your mains
voltage!
Prior to starting operation with the PM300 optical power meter, check if the line
voltage set with the voltage selector at the rear panel agrees with your local supply
and if the appropriate fuses are inserted. (See chapter 6.2 on page 58 to change the
line voltage and chapter 6.3 on page 59 to exchange the mains fuses.)
Turn the unit on by pressing the line switch.
After switching on the unit, the graphics display will show the device status and then
jump to the dual channel screen.
The PM300 is immediately ready to use after turning on. The rated accuracy is
reached, however, after a warming-up time of approx. 10 minutes.

2.3 Physical Overview
11
Via the banana connector jack of the chassis ground the external optical build-up can
be connected to ground potential, if required.
2.3 Physical Overview
2.3.1 Operating Elements at the Front Panel
Figure 1 Display and Operating Elements at the Front Panel
Power Switch Soft Keys Photodiode Inputs
CH1; CH2
Display Selector
CH1; CH2; CH1 & CH2;
Chart Mode
Control Knob

2.3 Physical Overview
12
2.3.2 Operating Elements at the Rear Panel
Figure 2 Operating Elements at the Rear Panel
Ground Connector
(4mm banana)
USB Interface
Connector
(Type ‘B’)
Misc. Out:
Programmable
Analog Output
(BNC) CH1 PD & TH
Sensor Connector
(SubD 9p fem.)
Mains Connector
Including line switch
and fuses
Analog Outputs
CH1, CH2
(BNC)
CH2 PD Sensor
Connector
(SubD 9p fem.)

2.3 Physical Overview
13
2.3.3 Main Screens
Figure 3 Dual Channel Screen
Figure 4 Single Channel Screen (CH1)
Figure 5 Trend Graph Channel 1
Channel Header with Display, Channel and Sensor Information
Main Display
Sub Display
Bargraph
(Main Display)
Directly
accessible
Menus
Soft Keys
Main Display CH1
Main Display CH2

3.1 Sensor independent Operation and Settings
14
3 Operating the PM300
3.1 Sensor independent Operation and Settings
3.1.1 Navigating the Menus
The PM300 is controlled by three display/menu dependent soft buttons below the
graphics display and/or the control knob including a push button with an Edit/Enter
functionality. All displays have directly accessible menus by navigating and clicking
with the Multi-Control knob.
To select the channel and the graph displays two buttons CH1 and CH2 with LED
indicators are used (ON means lit LED; pressing the buttons toggles the LEDs):
CH 1 CH 2 Display
ON OFF Channel 1; Single Channel Screen
OFF ON Channel 2; Single Channel Screen
ON ON Channel 1 + Channel 2; Dual Channel Screen
OFF OFF Trend Graph Screen; Measurement value according <Graph
Setup> menu or toggling the <Graph Display> soft button
3.1.2 System Settings
To enter the system settings press the Menu button that is located at the left soft
button position in the channel and graph screens. The following sub-menus will
appear:
•Channel 1 Setup
Depending on the connected sensor the displays and the sensor specific
parameters can be set
•Channel 2 Setup
Depending on the connected sensor the displays and the sensor specific
parameters can be set
•Graphics Configuration
Configures the measurement value, time-base, offset shift and gain for the
graphical representation.
•User Wavelength
Allows to enter five correction wavelengths for quick access.

3.1 Sensor independent Operation and Settings
15
•Miscellaneous Output Configuration
Configures the measurement value, sensitivity and offset of the programmable
analog output (MISC OUT).
•System Configuration
Contains hard-ware adjustments like LCD illumination and 50/60Hz line filter
setting; and system information.
3.1.3 Readout Configuration
The main-display can be configured in terms of units of measure and also with
mathematical functions between the two channels. To select the main display toggle
the <CHx Display> button or go to the <CHx Setup> and chose the ‘Main Display’
menu.
The sub display that is visible as small read out value in the single channel screen
can be configured in the <CHx Setup> and the ‘Sub Display’ menu. For this display
the power value can be set in linear (W) and logarithmic (dBm) mode
The following main displays can be selected, the channel headers show the
information of the current display:
Sensor Main Display (CH 1) Main Display (CH 2)
All Power [dBm] Power [dBm]
All Power [W] Power [W]
All Delta Power [dB] Delta Power [dB]
All Delta Power [W] Delta Power [W]
All Ratio CH1/CH2 [dB] Ratio CH1/CH2 [dB]
All Power Difference CH1-CH2 [W] Power Difference CH1-CH2 [W]
PD Input Current [A] Current [A]
TH Adapter Voltage [V] N/A
3.1.4 Range Setting
The PM300 provides sensor dependent up to seven power corresponding current
and up to four power corresponding voltage measurement ranges that can be
selected in manual- and auto-range mode. To select a range or switch to the auto-
range mode navigate to the ‘Range’ menu or in the setup screen to the ‘Power
Range’ menu and click the button to edit the range setting menu. Depending on the
sensor type you can chose between several power ranges and the auto-range mode
either by turning the control knob or using the <Down> and <Up> soft keys. The

3.1 Sensor independent Operation and Settings
16
selected range immediately gets active after selecting. To leave the menu press the
control knob or the <ok> soft key.
When power-meter sensors are connected the ranges will show in Watts; for the
photodiode inputs in Ampere, for the thermal head adapter in Volts.
Figure 6 Range Setting with a photodiode sensor
3.1.5 Relative Power Measurement
This feature can be used to observe power drifts, adjust power to a certain level, or
quickly subtract ambient light.
Navigating to the ‘∆P’ menu and clicking the Multi-Control knob toggles between
relative and absolute power measurement. When the relative power measurement is
activated by clicking the Multi-Control knob the header changes to ‘Delta Power’, the
current power reading gets zeroed, the bar-graph goes to a zero middle-position, the
subtracted value gets indicated in the ‘∆P’ menu and the measurement range
switches one range down. From this point of time the main display and the bar-graph
shows the difference to the subtracted power in W or dBm. The sub display still
shows the absolute power level. A Range setting is still possible as described in the
paragraph above.
Figure 7 Relative Power Measurement with a photodiode sensor

3.2 Operation with a Photodiode Sensor
17
3.1.6 Setting an Attenuation Factor
The Attenuation Menu enables to set a user calibration factor to the power reading.
This is very convenient when wanting to read the ‘real’ laser power, but having an
additional filter or beam splitter in the system.
To enter an attenuation factor, press the <CHx Setup> soft button, navigate and click
the ‘Attenuation’ menu. Set the desired attenuation in dB and press <ok> or click the
control button. Exit the setup menu.
Figure 8 Attenuation
3.2 Operation with a Photodiode Sensor
Photodiode sensors of the Thorlabs S1xx series can be connected to each of the
Sub-D jacks in the rear panel. The sensor will be recognized immediately after
plugging. When a power meter sensor is plugged the related photo-diode input in the
front panel gets inactive.
Attention 
Refer to the sensor data sheet and pay attention to the optical
damage threshold!
Exceeding these values will permanently destroy the sensor!
For the measurement of small power levels up to approximately 1-2 W photodiode
sensors have a lot of advantages against thermal sensors. The sensors are built up
in a combination of a photodiode and a neutral density filter or a photodiode in
combination with an integrating sphere. They provide linearity over several decades

3.2 Operation with a Photodiode Sensor
18
and show a great sensitivity for very small power levels down to the nW range.
Handling fairly small power levels the form factor can be held small, further the
response time of such a sensor is in the ns to µs range.
Photodiodes, neutral density filters and also integrating sphere materials show a
wavelength dependent behaviour and therefore each sensor is individually calibrated
over the spectral working range in 5nm steps. Each sensors spectral responsivity
data gets stored in a non-volatile memory inside the DB-9 sensor connector and
downloaded to the PM300 when plugged to the unit. To perform an accurate
measurement it is necessary to enter the operating wavelength that the PM300 can
calculate the laser power from the measured photo current and the right responsivity
value from the wavelength calibration table.
Figure 9 Readout and Setup Screen for a Photodiode Sensor
3.2.1 Wavelength Correction
As described above it is necessary to enter the wavelength of the light to measure for
an accurate calibrated measurement.
The wavelength setting can be edited by navigating to the ‘λ’ Menu in the
measurement displays or the channel setup and clicking on the control knob. The
menu gets a blinking frame and the value can be increased or decreased with by
turning the control knob. Further two soft buttons with <prev. λuser> and <next
λuser> appear; pressing these buttons the correction wavelength can be toggled
between the 5 preconfigured wavelengths from the systems menu ‘user wavelength’.
The new wavelength setting gets active when pressing the control button or the <ok>
soft-key.