Our complete selection of laser diodes is available on the LD Selection Guide tab above.
Clicking this icon opens a window that contains specifications and mechanical drawings.
Clicking this icon allows you to download our standard support documentation.
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 L-I-V and spectral measurements for that serial-numbered device.
Polarization-Maintaining Pigtails from 635 nm to 1550 nm
Internal Fiber Cleaved at 8° Angle
1 m of PM Fiber with FC/PC Connector (2.0 mm Narrow Key)
Slow Axis of Fiber Aligned to Connector Key
Custom Pigtails Available Upon Request
This webpage contains Thorlabs' pigtailed laser diodes with polarization-maintaining (PM) fiber. Diodes are arranged by wavelength and then power. The tables below list basic specifications to help you narrow down your search quickly. The blue button in the Info column within the tables opens a pop-up window that contains more detailed specifications for each item, as well as mechanical drawings.
Our high-quality PM pigtail alignment process for laser diodes includes multiple test and inspection points that ensure that the coupling efficiency is maximized. In addition, the input end of the fiber is cleaved at an 8° angle in order to minimize back reflections that can cause the output intensity to fluctuate. Polarization-maintaining pigtails provide coherent fiber-coupled output from a laser diode. We offer versions based on TO-packaged diodes (Ø5.6 or Ø9 mm). In each pigtailed package, the slow axis of the fiber is aligned to the 2.0 mm narrow key of the FC/PC connector.
While the center wavelength is listed for each laser diode, this is only a typical number. The center wavelength of a particular unit varies from production run to production run, so the diode you receive may not operate at the typical center wavelength. After clicking "Choose Item" below, a list will appear that contains the center wavelength, output power, and operating current of each in-stock unit. Clicking on the red Docs Icon next to the serial number provides access to a PDF with serial-number-specific L-I-V and spectral characteristics. Diodes can be temperature tuned, which will alter the lasing wavelength.
The reliability of the laser diode/pigtail rapidly declines at higher temperatures. Therefore, for stable output power and wavelength, it is highly recommended that you use a temperature controller with these products.
Laser diodes are sensitive to electrostatic shock. Please take the proper precautions when handling the device. Fabry-Perot lasers are also sensitive to optical feedback, which can cause significant fluctuations in the output power of the laser diode depending on the application.
We recommend cleaning the fiber connector before each use if there is any chance that dust or other contaminants may have deposited on the surface. The laser intensity at the center of the fiber tip can be very high and may burn the tip of the fiber if contaminants are present. While the connectors on these pigtailed laser diodes are cleaned and capped before shipping, we cannot guarantee that they will remain free of contamination after they are removed from the package. For all of these pigtailed laser diodes, the laser must be off when connecting or disconnecting the device from other fibers, particularly for lasers with power levels of 10 mW or higher.
Please contact Technical Support if you would like a quote on custom pigtailed laser diodes or for a volume order.
Ø5.6 mm and Ø9 mm Pin Configurations
For warranty information, please refer to the LD Operation tab.
The drawing to the right shows a laser diode's emitted light focused into an angle-polished fiber. By angling the ferrule 8°, light that is not coupled into the optical fiber is reflected away from the laser diode. If this reflected light were reflected back toward the diode, light would be coupled into the diode and cause fluctuations in power and wavelength.
Further Reducing Back Reflection Although we use a fiber coupling design that minimizes back reflections, other factors may couple light back into the fiber. Many of our standard pigtailed laser diodes feature optical fiber with an FC/PC connector. When the FC/PC connector is not connected directly to another FC/PC connector, about 4% of light in the fiber is reflected back toward the laser diode due to the silica/air interface. Customers who require a silica/air interface or minimal back reflections in their application can contact Tech Support to request FC/APC connectors. As FC/APC connectors have an angled polish, light reflected back toward the diode will be further minimized.
Laser Diode and Laser Diode Pigtail Warranty
When operated within their specifications, laser diodes have extremely long lifetimes. Most failures occur from mishandling or operating the lasers beyond their maximum ratings. Laser Diodes are among the most static-sensitive devices currently made. Proper ESD Protection should be worn whenever handling a laser diode. Due to their extreme electrostatic sensitivity, laser diodes cannot be returned after their sealed package has been open. Laser diodes in their original sealed package can be returned for a full refund or credit.
Handling and Storage Precautions
Due to their extreme susceptibility to damage from electrostatic discharge (ESD), care should be taken whenever handling and operating laser diodes:
Laser Diode Storage: When not in use, short the leads of the laser together to protect against ESD damage.
Operating and Safety Precautions
Use an Appropriate Driver: Laser diodes require precise control of operating current and voltage to avoid overdriving the laser diode. In addition, the laser driver should provide protection against power supply transients. Select a laser driver appropriate for your application. Do not use a voltage supply with a current limiting resistor since it does not provide sufficient regulation to protect the laser.
Power Meters: When setting up and calibrating a laser diode with its driver, use a NIST-traceable power meter to precisely measure the laser output. It is usually safest to measure the laser output directly before placing the laser in an optical system. If this is not possible, be sure to take all optical losses (transmissive, aperture stopping, etc.) into consideration when determining the total output of the laser.
Reflections: Flat surfaces in the optical system in front of a laser diode can cause some of the laser energy to reflect back onto the laser’s monitor photodiode giving an erroneously high photodiode current. If optical components are moved within the system and energy is no longer reflected onto the monitor photodiode, a constant power feedback loop will sense the drop in photodiode current and try to compensate by increasing the laser drive current and possibly overdriving the laser. Back reflections can also cause other malfunctions or damage to laser diodes. To avoid this, be sure that all surfaces are angled 5-10°, and when necessary, use optical isolators to attenuate direct feedback into the laser.
Heat Sinks: Laser diode lifetime is inversely proportional to operating temperature. Always mount the laser in a suitable heat sink to remove excess heat from the laser package.
Voltage and Current Overdrive: Be careful not to exceed the maximum voltage and drive current listed on the specification sheet with each laser diode, even momentarily. Also, reverse voltages as little as 3 V can damage a laser diode.
ESD Sensitive Device: Currently operating lasers are susceptible to ESD damage. This is particularly aggravated by using long interface cables between the laser diode and its driver due to the inductance that the cable presents. Avoid exposing the laser or its mounting apparatus to ESDs at all times.
ON/OFF and Power Supply Coupled Transients: Due to their fast response times, laser diodes can be easily damaged by transients less than 1 µs. High current devices such as soldering irons, vacuum pumps, and fluorescent lamps can cause large momentary transients. Thus, always use surge-protected outlets.
If you have any questions regarding laser diodes, please call your local Thorlabs Technical Support office for assistance.
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.
Safe Practices and Light Safety Accessories
Thorlabs recommends the use of safety eyewear whenever working with laser beams with non-negligible powers (i.e., > Class 1) 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.
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.
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:
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 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 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).
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.
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 are limited to 5 mW of output power in this class.
Class 3B lasers are hazardous to the eye if exposed directly. However, diffuse reflections are not harmful. Safe handling of devices in this class includes wearing protective eyewear where direct viewing of the laser beam may occur. In addition, laser safety signs lightboxes should be used with lasers that require a safety interlock so that the laser cannot be used without the safety light turning on. Class-3B lasers must be equipped with a key switch and a safety interlock.
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.
All class 2 lasers (and higher) must display, in addition to the corresponding sign above, this triangular warning sign
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The rows shaded green below denote single-frequency lasers.