Turnkey MIR Laser Systems


  • Plug-and-Play Benchtop Laser Systems
  • Fabry-Perot (4.00 µm or 4.55 µm) or Distributed Feedback (4 - 5 µm)
  • Collimated CW Output
  • Each System Includes a Laser Head & Touchscreen Controller

MLQF4550

4.55 µm CWL, 250 mW
Fabry-Perot Laser

Related Items


Please Wait
Home Screen
Click to Enlarge
Touchscreen Controller Interface
Each turnkey MIR laser system includes a touchscreen controller that provides easy access to all laser parameters. More details are given in the Controller Interface tab.
MIR Laser Types
Fabry-Perot TO Can
Two-Tab C-Mount
D-Mount
HHL
Turnkey
Distributed
Feedback		 Two-Tab C-Mount
D-Mount
HHL
Turnkey
  • Custom Fabry-Perot lasers with HHL or
    D-Mount housings are available; contact Tech Support with inquiries.
FP and DFB Comparison
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Fabry-Perot and Distributed Feedback Laser Comparison
Fabry-Perot (FP) Lasers have broadband emission, while Distributed Feedback (DFB) Lasers emit at a well defined wavelength.

Turnkey Quantum Cascade Lasers (QCL)

  • Fabry-Perot Lasers Offered from Stock:
    • 4.00 µm or 4.55 µm Center Wavelength (CWL), 250 mW (Min)
    • Broadband Emission
  • Distributed Feedback (DFB) Lasers Offered from Stock:
    • Single-Frequency CWL Available from 4 - 5 µm, 40 mW (Typ.)
    • CWL Tunable Over a 1 to 5 cm-1 Range
  • Fabry-Perot & DFB Lasers from 3 to 12 µm Available Made-to-Order (See Graph Below)
  • Easy-to-Use Touchscreen Controller
  • Internal and External Modulation at up to 100 kHz
  • Integrated Interlock Circuit and Hand-Operated Shutter
  • Higher Output Powers Available by Contacting Tech Support

Thorlabs' Turnkey MIR Lasers are ready-to-use, ultra-low-maintenance laser systems that provide collimated CW output in the MIR. Each laser system consists of a single-spatial-mode quantum cascade laser head that is operated by a touchscreen current / temperature controller with a 4.3" LCD. Using the same automated test stations that qualify our packaged MIR laser chips, we measure the wavelength and L-I-V characteristics of each laser head at the factory, then store the test results on an EEPROM inside the laser head enclosure. This EEPROM allows the controller to automatically adjust itself for calibrated plug-and-play operation.

In general, Fabry-Perot lasers offer higher power and broadband emission, while DFB lasers provide single-wavelength emission that can be tuned over a 1 to 5 cm-1 range, depending upon the chip (see the Specs tab). Fabry-Perot lasers available from stock emit at either a 4.00 µm or 4.55 µm CWL with a minimum output power of 250 mW. Stocked DFB lasers feature a CWL within the 4 - 5 µm range, and this emission wavelength is temperature- and current-tunable over a narrow range that varies for each device. Item-specific information such as the factory-measured spectrum, output power, and beam profile of each stocked item is available by clicking "Choose Item" below. Additionally, custom Fabry-Perot and DFB lasers at CWLs from 3 to 12 µm (refer to the graph below) are available by contacting Tech Support.

Custom QCL Wavelengths
Click to Enlarge
Wavelengths Available as Custom Orders
Custom turnkey MIR lasers are available with typical lead times of 12 to 14 weeks. In the past, we have manufactured lasers at all of the wavelengths shown above. Please contact us with inquiries.

Touchscreen Controller
The controller enables local and remote control of the laser's optical output. A resistive touch screen allows for the screen to be operated when using gloves or other protective equipment. Screenshots of the interface are available in the Controller Interface tab. The back of the controller includes three SMA connectors: an external modulation input for sine, triangle, or square waves; an external tuning input for fine tuning DFB lasers to a spectral absorption line and locking the wavelength using error signal feedback; and a TTL synchronization output. A 2.5 mm mono jack is included for interlock connections, and a 4 mm banana jack is included for use with a ground pin. In addition, a USB 2.0 mini B connector allows remote operation using software written by the user in C, C++, C#, LabVIEW®, LabWindows™/CVI, or Visual Studio.

Air-Cooled Laser Head
The laser head contains the laser chip and a collimating aspheric lens. The only connection between the laser head and controller is made through the included HD DB26 cable. A built-in thermistor and thermoelectric cooler (TEC) allow the controller to set and actively regulate the laser chip's temperature, while an automatic over-temperature shutoff protects the laser from thermal damage. No chiller lines are required.

Three SWB/M Mounting Feet provide a nominal beam height of 67.0 mm. These individually adjustable feet allow for coarse beam height adjustment over a ±10.0 mm range and contain swivel joints, allowing the beam pointing to be adjusted while keeping the laser level with the optical table. When the mounting feet are locked down by a clamping fork, the angle of each foot becomes fixed. Three CF175 Clamping Forks are included with the laser head.

When installing the laser system, note that air vents are located on the top, sides, and bottom of the laser head, so it is necessary to leave adequate room near the vents for air circulation. The laser head should not be operated while the mounting feet are removed.

Fabry-Perot Laser Heads

Spectrum
Click to Enlarge
This sample spectrum is measured at 25 °C. Each device has a unique spectrum. To get the spectrum of a specific, serial-numbered device, click "Choose Item" below, then click on the Docs Icon next to the serial number. If you need spectral characteristics different than those shown, please contact Tech Support to inquire about a custom laser.
Spectrum
Click to Enlarge
This sample spectrum is measured at 25 °C. Each device has a unique spectrum. To get the spectrum of a specific, serial-numbered device, click "Choose Item" below, then click on the Docs Icon next to the serial number. If you need spectral characteristics different than those shown, please contact Tech Support to inquire about a custom laser.
Optical Specifications
Item # MLQF4000 MLQF4550
Characteristic Minimum Typical Maximum Minimum Typical Maximum
Center Wavelength 3.90 µm 4.00 µm 4.10 µm 4.45 µm 4.55 µm 4.65 µm
Optical Output Powera 250 mW - <500 mWb 250 mW - <500 mWb
Spectral Bandwidth
(5 - 95% Integrated Power)		 - 130 nm - - 130 nm -
Beam Pointing Horizontal -0.3° 0° +0.3° -0.3° 0° +0.3°
Verticalc -0.3° 0° +0.3° -0.3° 0° +0.3°
Beam Divergenced Horizontal - 3.5 mrad - - 3.5 mrad -
Vertical - 3.0 mrad - - 3.0 mrad -
M2 (See Footnote a) Horizontal 1 - 1.3 1 - 1.3
Vertical 1 - 1.3 1 - 1.3
Sample Beam Profile (Click to Enlarge)
Sample L-I-V Curve (Click to Enlarge)
Output Power Stability over Operating
Temperature Range (+15 to +35 °C)		 -3% - +3% -3% - +3%
Output Power Stability over 24 Hours at
Room Temperature		 -2.5% - +2.5% -2.5% - +2.5%
Laser Current - - 1.2 A - - 1.2 A
  • The M2 value is guaranteed at the minimum optical output power of the laser head. Operation beyond the minimum output power may result in some reduction in beam quality.
  • Lasers with a higher optical output power are possible; please contact Tech Support with requests.
  • The SWB/M Mounting Feet on the bottom of the laser head allow the user to adjust the vertical beam pointing.
  • Beam data is obtained from camera images taken at several distances from the laser emitter. Beam width at each point is extracted using the second order moment of the power distribution and beam parameters are determined from a hyperbolic fit of the beam width versus the propagation distance.


Physical Specifications
Dimensions (W x H x D) 114.0 mm x 132.8 mm x 208.4 mm
(4.49" x 5.23" x 8.21")
Operating Temperature Rangea +15 to +35 °C, Non-Condensing
Storage Temperature Range 0 to +50 °C, Non-Condensing
Weight of Laser Head 2.1 kg (4.6 lbs)
Laser Class 3B (Output Power <500 mW)
  • This temperature range is for the ambient room temperature.


Spectrum
Click to Enlarge
Individually-normalized sample spectrum showing tuning under varying current and internal temperature conditions. Each device has a unique spectrum. To get the spectrum of a specific, serial-numbered device, click "Choose Item" below, then click on the Docs Icon next to the serial number. If you need spectral characteristics different than those shown, please contact Tech Support to inquire about a custom laser.
Spectrum
Click to Enlarge
Plot of output power with wavenumber tuning using Wavelength or Wavenumber Interpolation Mode

Distributed-Feedback (DFB) Laser Head

Optical Specifications
Item # MLQD4500
Characteristic Minimum Typical Maximum
Center Wavelength 4.00 µm - 5.00 µm
Optical Output Powera 5 mW 40 mW -
Side Mode Supression Ratio (SMSR) 20 dB - -
Beam Pointing Horizontal -0.3° 0° +0.3°
Verticalb -0.3° 0° +0.3°
Beam Divergencec Horizontal - 3.5 mrad -
Vertical - 3.0 mrad -
M2 (See Footnote a) Horizontal 1 - 1.3
Vertical 1 - 1.3
Sample Beam Profile (Click to Enlarge)
Sample L-I-V Curve (Click to Enlarge)
Output Power Stability over Operating Temperature Range
(+15 to +35 °C)		 - ±3% -
Output Power Stability over 24 Hours at Room Temperature - ±2.5% -
Output Wavelength Stability over Operating Temperature Range
(+15 to +35 °C)c		 - 0.125 cm-1
(0.25 nm)		 -
  • The M2 value is guaranteed at the minimum optical output power of the laser head. Operation beyond the minimum output power may result in some reduction in beam quality.
  • The SWB/M Mounting Feet on the bottom of the laser head allow the user to adjust the vertical beam pointing.
  • Beam data is obtained from camera images taken at several distances from the laser emitter. Beam width at each point is extracted using the second order moment of the power distribution and beam parameters are determined from a hyperbolic fit of the beam width versus the propagation distance.


Physical Specifications
Dimensions (W x H x D) 114.0 mm x 132.8 mm x 208.4 mm
(4.49" x 5.23" x 8.21")
Operating Temperature Rangea +15 to +35 °C, Non-Condensing
Storage Temperature Range 0 to +50 °C, Non-Condensing
Weight of Laser Head 2.1 kg (4.6 lbs)
Laser Class 3B (Output Power <500 mW)
  • This temperature range is for the ambient room temperature. For the allowable internal temperature operating range, please see the item-specific data sheets.

MLSC Laser Controller

Laser Controller Specifications Laser Controller Setting
(If Applicable)a		 Front Panelb Remote Controlb
Laser Current Control
Polarity Cathode Grounded (CG)
Current Control Range 0 to 1.2 Ac
Current Control Resolution 100 µA 20 µA
Current Control Accuracy ±(0.1% + 500 µA)
Current Limit Range 10 mA to 1.2 Ac
Current Limit Resolution 100 µA 20 µA
Current Limit Accuracy ±(0.2% + 1 mA)
Noise and Ripple
(Typical; RMS; 10 Hz to 10 MHz;
Current < 600 mA; 33 Ω Load)		 Noise Reduction Off 10 µA
Noise Reduction On 5 µA
Drift
(24 Hours; Typical; 0 Hz to 10 Hz; at Constant Ambient Temperature)		 <50 µA
Temperature Coefficient <50 ppm / °C
Laser Compliance Voltage
Compliance Voltage 20 V
Compliance Voltage Measurement Resolution 10 mV 1 mV
Compliance Voltage Measurement Accuracy ±(0.2% + 10 mV)
Internal Modulation
Amplitude of Modulation Current 0 mA to Current Limit (Peak to Peak)
See Laser Setup Screen in Controller Interface Tab
Sine Wave Bandwidth Noise Reduction Off 10 Hz to 100 kHzd
Noise Reduction On 10 Hz to 1 kHz
Triangle Wave Bandwidth Noise Reduction Off 10 Hz to 10 kHz
Noise Reduction On 10 Hz to 300 Hz
Square Wave Bandwidth Noise Reduction Off 10 Hz to 10 KHz
Noise Reduction On 10 Hz to 300 Hz
External Modulation Input
(3 dB Bandwidth; for Small Signals <±5% of Maximum Drive Current of 1.2 A; Measured with 5 Ω Load)
Input Connector SMA Connector
Input Voltage Range -10 to +10 V
Input Impedance 10 kΩ
External Modulation Coefficient Low Sensitivity 12 mA/V ± 5%
High Sensitivity 120 mA/V ± 5%
Sine Wave Bandwidth Noise Reduction Off DC to 100 kHz
Noise Reduction On DC to 4 kHz
Triangle Wave Bandwidth Noise Reduction Off DC to 40 kHz
Noise Reduction On DC to 1.5 kHz
Square Wave Bandwidth Noise Reduction Off DC to 20 kHz
Noise Reduction On DC to 1 kHz
Tune Input
Input Connector SMA Connector
Input Voltage Range -10 to +10 V
Input Impedance 10 kΩ
Tune Modulation Coefficient 6 mA/V ± 5%
Sync Output
Output Connector SMA Connector
Logic Level TTL
Low Level <0.3 V
High Level >2.5 V (50 Ω Load)
>3.5 V (10 kΩ Load)
Delay in Modulated Current with
Respect to Sync Output		 Noise Reduction Off 3 µs
Noise Reduction On 30 µs
Temperature Control
Temperature Control Rangee (Tset)
 0 to +50 °C
Temperature Resolution 0.01 °C
Temperature Stability (24 Hours; Typical) <0.005 °C
Temperature Window Setting Rangee (Twin) 0.01 to 25.0 °C
Delay for Protection Reset 0 to 600 s
  • The noise reduction filter can be toggled between on and off in the Laser Setup screen of the controller (see Section 4.5 of the manual). The external modulation sensitivity can be toggled between low and high in the Modulation screen of the controller (see Section 4.7 of the manual).
  • When using the controller's front panel, many resolution settings are limited by the display. Higher resolution for these settings can be achieved through user-written software, following the programming references in the Software tab.
  • Although the controller can provide up to 1.2 A of current, the laser head's EEPROM will limit the maximum current to a factory-determined value. The user may independently set a current limit up to this factory-determined value.
  • At frequencies ≤30 kHz, the modulation current amplitude will remain within ±5% of the user-commanded value. Beyond 30 kHz, this tolerance worsens, up to a maximum of 3 dB at 100 kHz. The controller displays a warning when 30 kHz is exceeded.
  • If the temperature of the laser head exceeds the range given by Tset ± Twin, the laser current will be paused or switched off (see Section 4.6 of the manual).

All technical data are valid at 23 ± 5 °C and 45 ± 15% relative humidity. All accuracy specs are valid after a 30-minute warm-up period.

General Laser Controller Specifications
Safety Features Interlock, Keylock Switch, Laser Current Limit, Soft Start, Overtemperature Protection, Temperature Window Protection, and Switch-On Delay (3 to 60 s)
Display 4.3" LCD TFT, 480 x 272 Pixels
Connector for DC Power Input 4-Pin Mini-DIN Connector
Connector for External Modulation Input Female SMA
Connector for Tune Input Female SMA
Connector for Sync Output Female SMA
Connector for Interlock and
Laser On Signal		 2.5 mm Mono Jack
Connector for USB Interface USB Type Mini-B
Chassis Ground Connector 4 mm Banana Jack
Warm-Up Time for Rated Accuracy 30 min
Power Input 100 to 240 VAC ± 10%; 47 to 63 Hz
Maximum Power Consumption 180 VA
Dimensions (W x H x D) 112.0 mm x 85.0 mm x 197.3 mm
(4.41" x 3.35" x 7.77")
Weight (with Power Supply) 1.6 kg (3.52 lbs)
Operating Temperature 0 to +40 °C
Storage Temperature -40 to +70 °C

Controller Interface

The touchscreen controller uses an intuitive two-level menu hierarchy. The Home screen displays the laser's setpoints and actual values, while the Menu screen gives access to all settings screens. Large characters are used for the laser's operating parameters, making them easy to read at a distance.

In order to change a parameter, simply tap it with your finger or a stylus to enable the editor. The Home and Menu screens are never more than one tap away, unless the user is currently editing a parameter.

A persistent status bar at the bottom of the screen provides laser and TEC toggles, along with status indicators for the keylock, interlock circuit, laser over-temperature protection circuit, and current limits.

 

Selected Screens

Home Screen
Click to Enlarge
Home Screen
The Home screen displays the laser's setpoints and actual values, and gives access to four user-defined setpoints. When the controller is powered on, it recalls the last used settings.
Menu Screen
Click to Enlarge
Menu Screen
Tapping the Menu button at the bottom right brings up the Menu screen, which gives access to all settings screens.
Modulation Screen
Click to Enlarge
Modulation Screen
For sine waveforms, the maximum frequency range for internal modulation is 10 Hz to 100 kHz, while for triangle and square waveforms, it is 10 Hz to 10 kHz. External modulation from DC to 100 kHz is supported by the SMA connector on the controller.
Laser Setup Screen
Click to Enlarge
Laser Setup Screen
Displays the factory-measured center wavelength, optical output power, maximum forward voltage, and maximum drive current. Changing "FP Laser Interpolation Type" from NONE to POWER allows the user to request a specific output power in mW. For DFB laser heads, users can also set the output spectrum as a wavelength or wavenumber.
TEC Driver Setup Screen
Click to Enlarge
TEC Driver Setup Screen
Provides settings for the TEC current limit, lower temperature limit, and upper temperature limit.
System Settings Screen
Click to Enlarge
System Settings Screen
Used to configure the display brightness from 20% to 100% and to toggle the wavelength display between nm and cm-1.

Pin Diagrams

Rear of Laser
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The back of the laser head has a female HD DB26 connector that connects to the laser controller.
Rear of Controller
Click to Enlarge
The back of the laser controller has
all the other connectors.

Modulation In

SMA Female

SMA Connector
Modulation In
Parameter Laser Controller Setting
(If Applicable)		 Value
Input Impedance 10 kΩ
Input Voltage -10 to +10 V
Modulation Coefficient
of Drive Current
 Low Sensitivity 12 mA/V ± 5%
High Sensitivity 120 mA/V ± 5%
Input
Frequencya		 Sine
Wave		 Noise Reduction Off DC to 100 kHz
Noise Reduction On DC to 4 kHz
Triangle
Wave		 Noise Reduction Off DC to 40 kHz
Noise Reduction On DC to 1.5 kHz
Square
Wave		 Noise Reduction Off DC to 20 kHz
Noise Reduction On DC to 1 kHz
  • 3 dB Bandwidth; Measured with 5 Ω Load; for Small Signals <±5% of Maximum Drive Current of 1.2 A

The sensitivity level of the modulation coefficient and the status of the noise reduction filter are configured in the Laser Setup Screen (see the Controller Interface tab). Activating the noise reduction filter reduces the drive current noise by approximately 2X.

Tune In

SMA Female

SMA Connector
Tune In
Parameter Value
Input Impedance
 10 kΩ
Input Voltage -10 to +10 V
Modulation Coefficient
of Drive Current		 6 mA/V ± 5%

The Tune In input is used to fine tune a DFB laser to a spectral absorption line and lock the wavelength using error signal feedback.

Sync Out

SMA Female

SMA Connector
Sync Out
Parameter Value
Low Level <0.3 V
High Level 50 Ω Impedance >2.5 V
10 kΩ Impedance >3.5 V
Delay in Modulated Current
with Respect to Sync Out		 Noise Reduction Off 3 µs
Noise Reduction On 30 µs

The TTL output signal switches from low to high when the internal modulation signal increases past zero.

Computer Control

Female USB Mini B

USB Mini B

This interface allows a computer to change the controller's settings using an SCPI-compliant command set (see the Software tab) and is used to load firmware upgrades via a Windows® operating system.

Interlock

2.5 mm Mono Jack

2.5 mm Mono Jack

This connector must be short-circuited to enable laser emission. A jumper pin is included with the laser system.

Ground

4 mm Banana Jack

4 mm Banana Jack

If desired, the user may use this connector to ground the system.

Power Supply

Female 4-Pin Mini-DIN

4-Pin Mini DIN

This connector provides power for
the entire laser system.

Laser Head to Controller

Female HD DB26

HD DB26

One of these connectors is located on the laser head, and another is located on the laser controller. They are used to transmit signals and power.

Drivers for Remote Control of Touchscreen Controller

The download button below links to VXIpnp instrument drivers and support documentation for operating our turnkey MIR laser system with user-written software. The controller understands the SCPI-compliant command set described in the Programming Reference tab on the software download page. The C, C++, C#, LabVIEW®, LabWindows™/CVI, and Visual Studio programming environments are supported.

Drivers

Version 1.0 (February 16, 2017)

Software Download
All Items Included with Turnkey MIR Lasers
Click to Enlarge
Contents of MLQF4550 MIR Laser System Shown (North American Power Cord Shown)

Shipping List

Each turnkey MIR laser system includes:

  • Factory-Calibrated Laser Head
  • MLSC Touchscreen Controller
  • HD DB26 Cable for Connecting Laser Head to Controller
  • Three CF175 Clamping Forks for Securing Laser Head to Optical Table
  • VRC6S MIR Detector Card (Not Pictured)
  • USB 2.0 A to Mini B Cable for Remote Operation
  • Laser Enable Key (Qty. 2)
  • 2.5 mm Jumper Pin for Short Circuiting the Interlock (Ships Installed in Controller; Not Pictured)
  • Power Supply and Region-Specific Power Cord
  • Quick Start Guide
Laser Packages of QCLs
Click to Enlarge
Some of Our Available Packages
Wire Bonding
Click for Details
Wire Bonding a Quantum Cascade Laser on a C-Mount

Custom & OEM Quantum Cascade and Interband Cascade Lasers

At our semiconductor manufacturing facility in Jessup, Maryland, we build fully packaged mid-IR lasers and gain chips. Our engineering team performs in-house epitaxial growth, wafer fabrication, and laser packaging. We maintain chip inventory from 3 µm to 12 µm, and our vertically integrated facilities are well equipped to fulfill unique requests.

High-Power Fabry-Perot QCLs
For Fabry-Perot lasers, we can reach multi-watt output power on certain custom orders. The available power depends upon several factors, including the wavelength and the desired package.

DFB QCLs at Custom Wavelengths
For distributed feedback (DFB) lasers, we can deliver a wide range of center wavelengths with user-defined wavelength precision. Our semiconductor specialists will take your application requirements into account when discussing the options with you.

The graphs below and photos to the right illustrate some of our custom capabilities. Please visit our semiconductor manufacturing capabilities presentation to learn more.

Contact Thorlabs

Custom QCL Wavelengths
Click to Enlarge
Available Wavelengths for Custom QCLs and ICLs
High-Power QCLs
Click to Enlarge
Maximum Output Power of Custom Fabry-Perot QCLs
QCL Gain Chips
Click to Enlarge
Electroluminescence Spectra of Available Gain Chip Material

Laser Safety and Classification

Safe practices and proper usage of safety equipment should be taken into consideration when operating lasers. The eye is susceptible to injury, even from very low levels of laser light. Thorlabs offers a range of laser safety accessories that can be used to reduce the risk of accidents or injuries. Laser emission in the visible and near infrared spectral ranges has the greatest potential for retinal injury, as the cornea and lens are transparent to those wavelengths, and the lens can focus the laser energy onto the retina. 

Laser Glasses Laser Curtains Blackout Materials
Enclosure Systems Laser Viewing Cards Alignment Tools
Shutter and Controllers Laser Safety Signs

Safe Practices and Light Safety Accessories

  • Laser safety eyewear must be worn whenever working with Class 3 or 4 lasers.
  • Regardless of laser class, Thorlabs recommends the use of laser safety eyewear whenever working with laser beams with non-negligible powers, since metallic tools such as screwdrivers can accidentally redirect a beam.
  • Laser goggles designed for specific wavelengths should be clearly available near laser setups to protect the wearer from unintentional laser reflections.
  • Goggles are marked with the wavelength range over which protection is afforded and the minimum optical density within that range.
  • Laser Safety Curtains and Laser Safety Fabric shield other parts of the lab from high energy lasers.
  • Blackout Materials can prevent direct or reflected light from leaving the experimental setup area.
  • Thorlabs' Enclosure Systems can be used to contain optical setups to isolate or minimize laser hazards.
  • A fiber-pigtailed laser should always be turned off before connecting it to or disconnecting it from another fiber, especially when the laser is at power levels above 10 mW.
  • All beams should be terminated at the edge of the table, and laboratory doors should be closed whenever a laser is in use.
  • Do not place laser beams at eye level.
  • Carry out experiments on an optical table such that all laser beams travel horizontally.
  • Remove unnecessary reflective items such as reflective jewelry (e.g., rings, watches, etc.) while working near the beam path.
  • Be aware that lenses and other optical devices may reflect a portion of the incident beam from the front or rear surface.
  • Operate a laser at the minimum power necessary for any operation.
  • If possible, reduce the output power of a laser during alignment procedures.
  • Use beam shutters and filters to reduce the beam power.
  • Post appropriate warning signs or labels near laser setups or rooms.
  • Use a laser sign with a lightbox if operating Class 3R or 4 lasers (i.e., lasers requiring the use of a safety interlock).
  • Do not use Laser Viewing Cards in place of a proper Beam Trap.

 

Laser Classification

Lasers are categorized into different classes according to their ability to cause eye and other damage. The International Electrotechnical Commission (IEC) is a global organization that prepares and publishes international standards for all electrical, electronic, and related technologies. The IEC document 60825-1 outlines the safety of laser products. A description of each class of laser is given below:

Class Description Warning Label
1 This class of laser is safe under all conditions of normal use, including use with optical instruments for intrabeam viewing. Lasers in this class do not emit radiation at levels that may cause injury during normal operation, and therefore the maximum permissible exposure (MPE) cannot be exceeded. Class 1 lasers can also include enclosed, high-power lasers where exposure to the radiation is not possible without opening or shutting down the laser.  Class 1
1M Class 1M lasers are safe except when used in conjunction with optical components such as telescopes and microscopes. Lasers belonging to this class emit large-diameter or divergent beams, and the MPE cannot normally be exceeded unless focusing or imaging optics are used to narrow the beam. However, if the beam is refocused, the hazard may be increased and the class may be changed accordingly.  Class 1M
2 Class 2 lasers, which are limited to 1 mW of visible continuous-wave radiation, are safe because the blink reflex will limit the exposure in the eye to 0.25 seconds. This category only applies to visible radiation (400 - 700 nm).  Class 2
2M Because of the blink reflex, this class of laser is classified as safe as long as the beam is not viewed through optical instruments. This laser class also applies to larger-diameter or diverging laser beams.  Class 2M
3R Class 3R lasers produce visible and invisible light that is hazardous under direct and specular-reflection viewing conditions. Eye injuries may occur if you directly view the beam, especially when using optical instruments. Lasers in this class are considered safe as long as they are handled with restricted beam viewing. The MPE can be exceeded with this class of laser; however, this presents a low risk level to injury. Visible, continuous-wave lasers in this class are limited to 5 mW of output power.  Class 3R
3B Class 3B lasers are hazardous to the eye if exposed directly. Diffuse reflections are usually not harmful, but may be when using higher-power Class 3B lasers. Safe handling of devices in this class includes wearing protective eyewear where direct viewing of the laser beam may occur. Lasers of this class must be equipped with a key switch and a safety interlock; moreover, laser safety signs should be used, such that the laser cannot be used without the safety light turning on. Laser products with power output near the upper range of Class 3B may also cause skin burns.  Class 3B
4 This class of laser may cause damage to the skin, and also to the eye, even from the viewing of diffuse reflections. These hazards may also apply to indirect or non-specular reflections of the beam, even from apparently matte surfaces. Great care must be taken when handling these lasers. They also represent a fire risk, because they may ignite combustible material. Class 4 lasers must be equipped with a key switch and a safety interlock.  Class 4
All class 2 lasers (and higher) must display, in addition to the corresponding sign above, this triangular warning sign.  Warning Symbol

Posted Comments:
ebayri  (posted 2018-12-18 02:21:48.093)
Dear Sir/Madam, We are looking for single frequency (narrow band) QCL laser between 4.3-4.4um wavelength? Could you provide such product and what is the maximum power level for such unit? Can we specify wavelength during purchase order? Best regards,
YLohia  (posted 2018-12-21 10:06:29.0)
Hello, thank you for contacting Thorlabs. Custom items can be requested by emailing techsupport@thorlabs.com. It is possible to specify wavelengths before being formally quoted and the minimum output power required for your application should also be specified along with it. We can then check the feasibility of offering a custom solution suited for your needs.

Turnkey Fabry-Perot Quantum Cascade Lasers

Webpage Features
info icon Clicking this icon allows you to download our standard support documentation.

Choose Item

 Clicking the words "Choose Item" opens a drop-down list containing all of the in-stock lasers around the desired center wavelength. The red icon next to the serial number then allows you to download that device's data sheet.
Contact Thorlabs
  • Fabry-Perot Lasers with 4.00 µm or 4.55 µm CWL
  • 250 mW Minimum Output Power
  • Center Wavelengths from 3 to 12 µm Available by Contacting Tech Support
  • Includes Factory-Calibrated Laser Head, Touchscreen Controller, and All Other Items in Shipping List Tab

MIR Fabry-Perot lasers that emit at either a center wavelength of 4.00 µm or 4.55 µm with a minimum optical output power of 250 mW are available from stock. They exhibit broadband emission in a range spanning roughly 50 cm-1. The laser's specified output power is the sum over the full spectral bandwidth. Because these lasers have broadband emission, they are well suited for medical imaging, illumination, and microscopy applications. The optical output is vertically polarized.

Before shipment, the spectrum, output power, and beam profile are measured for each serial-numbered device by an automated test station. These measurements are available by clicking "Choose Item" below and are also included on a data sheet with the laser.

Since the EEPROM in the laser head contains all the values required for calibrated operation, it is possible to purchase additional laser heads and operate them with the same controller. Thorlabs' semiconductor foundry regularly fabricates laser chips that are suitable for these turnkey systems. To inquire about wavelength and output power availability, please contact Tech Support.

Based on your currency / country selection, your order will ship from Newton, New Jersey  
+1 Qty Docs Part Number - Universal Price Available
Choose ItemMLQF4000 Support Documentation
MLQF4000Turnkey Fabry-Perot Quantum Cascade Laser, 4.00 µm CWL, 250 mW (Min)
$14,428.24
Lead Time
This item is out of stock and currently has a  lead time
Choose ItemMLQF4550 Support Documentation
MLQF4550Turnkey Fabry-Perot Quantum Cascade Laser, 4.55 µm CWL, 250 mW (Min)
$14,428.24
Lead Time
This item is out of stock and currently has a  lead time

Turnkey Distributed-Feedback (DFB) Quantum Cascade Lasers

Webpage Features
info icon Clicking this icon allows you to download our standard support documentation.

Choose Item

 Clicking the words "Choose Item" opens a drop-down list containing all of the in-stock lasers around the desired center wavelength. The red icon next to the serial number then allows you to download that device's data sheet.
Contact Thorlabs
  • DFB Lasers with Single-Frequency Output
  • CWLs from 4 to 5 µm Available from Stock
  • CWL Tunable Over a 1 to 5 cm-1 Range
  • 5 mW Minimum, 40 mW Typical Output Power
  • Includes Factory-Calibrated Laser Head, Touchscreen Controller, and All Other Items in Shipping List Tab
  • Center Wavelengths from 4 to 11 µm Available by Contacting Tech Support

Distributed-Feedback (DFB) Quantum Cascade Lasers emit at a well-defined center wavelength within 4 to 5 µm and provide single spatial mode operation. By tuning the input current and internal temperature, the output frequency can be tuned over a narrow range between 1 cm-1 and 5 cm-1. They are ideal for chemical sensing, optical communications, and other applications.

Before shipment, the spectrum, output power, and beam profile are measured for each serial-numbered device by an automated test station. These measurements are available by clicking "Choose Item" below and are also included on a data sheet with the laser. Please note that the narrow tuning range for each serial-numbered DFB laser is specified on the support documentation; these lasers are not tunable over the entire 4 to 5 µm range.

Each laser head is shipped with an onboard EEPROM that contains the factory-measured center wavelength, L-I-V characteristics, and wavelength / wavenumber tuning characteristics. Since the EEPROM in the laser head contains all the values required for calibrated operation, it is possible to purchase additional laser heads and operate them with the same controller. Thorlabs' semiconductor foundry regularly fabricates laser chips that are suitable for these turnkey systems. To inquire about wavelength and output power availability, please contact Tech Support.

Based on your currency / country selection, your order will ship from Newton, New Jersey  
+1 Qty Docs Part Number - Universal Price Available
Choose ItemMLQD4500 Support Documentation
MLQD4500Turnkey DFB Quantum Cascade Laser, 4 - 5 µm CWL, 5 mW (Min)
$15,913.50
Lead Time
This item is out of stock and currently has a  lead time
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