Laser Diode Modules
Definition: modules containing diode lasers, and possibly also some optics, cooling devices, electrical elements, etc.
German: Laserdiodenmodule
Categories: photonic devices, laser devices and laser physics
Author: Dr. Rüdiger Paschotta
Cite the article using its DOI: https://doi.org/10.61835/kmv
Get citation code: Endnote (RIS) BibTex plain textHTML
Laser diodes are often used in the form of laser diode modules, i.e. packages which contain one or several laser diodes, in most cases combined with some optics and electronics. Such modules are much easier to use than bare laser diodes, as they serve a number of functions, as explained in the following. The optical output is either into free space – typically as a collimated beam, through a connected fiber or with a fiber connector.
Beam Shaping
For a laser diode module with free-space output, some optics (e.g. consisting of collimating lenses, micro-optics, and anamorphic prism pairs) can be used to shape the output beam, e.g. in order to obtain an approximately circular (or sometimes elliptical) beam with small divergence. Such a collimated beam can be more easily transmitted over some distance and more efficiently coupled to an optical fiber.
Important parameters e.g. for collimated outputs are the beam radius and beam divergence angle in both directions, the beam quality factor <$M^2$> and some measure for the beam pointing fluctuations (or the possible beam direction change during the warm-up time).
Other modules for specialized applications offer certain beam shapes, e.g. that of a line, a cross, an open circle, or a square.
Fiber Coupling
Some laser diode modules are fiber-coupled, i.e., directly launch the generated light into an optical fiber (“pig-tailed” laser diodes). For limited optical power, this may be a single-mode-fiber, which might even be polarization-maintaining, as the output is often linearly polarized. Otherwise, multimode fibers are common, and are the only option at high power levels.
Power and Wavelength Stabilization
The output power may be stabilized with an internal feedback loop with a monitor photodiode (often built into the actual laser diode). Some modules are very carefully stabilized to achieve a small relative intensity noise.
There are wavelength-stabilized modules, e.g. using passive stabilization with frequency-filtered optical feedback, or just temperature stabilization (see below). The output wavelength may drift somewhat more during the warm-up time after switching on the module.
Power Modulation
In some cases, the built-in electronics have an input for power modulation. Others are meant for continuous-wave operation with constant power only.
Pulse Generation
It is possible to obtain nanosecond or even picosecond light pulses from laser diode modules. For example, there are gain-switched modules with integrated driver electronics – which is important as very short electrical connections should be used for that mode of operation. In other cases, one uses quasi-continuous-wave operation with much longer pulse durations.
Wavelength Conversion
There are green laser diode modules with an internal frequency doubler. Such a module may contain an amplified single-mode laser diode and a nonlinear waveguide, for example.
Electrical Connections
A laser diode module may contain not only simple connections to the pins of the laser diode, but also additional electronic circuits, e.g. for protecting the laser diode against electrostatic discharge (ESD protection), wrong poling and too high operating voltages. Power stabilization (see above) and/or power monitoring is another possibility, also electronics for gain switching.
A module can often be operated directly with a battery or with an unstabilized power supply.
The module case may also provide effective shielding against external electromagnetic influences, which might otherwise affect the drive current and output power.
Cooling and Temperature Stabilization
For high powers, a laser diode module can facilitate the cooling, e.g. by offering a metallic surface which can easily be mounted on a cooler.
Temperature stabilization is also important for low-power diode modules, since the junction temperature influences the emission wavelength. A thermoelectric cooler (TEC) may also be included, often with a feedback system to stabilize the diode temperature. This leads to a more stable output wavelength and output power.
Applications
Applications of laser diode modules include precise pointing and alignment of optical elements, printing and imaging systems, displays, bar code scanning, optical data storage, optical sensors, pumping of solid-state lasers, free-space optical communications, and medical applications (e.g. photodynamic therapy, ophthalmology).
Many modules are used as OEM laser modules, i.e., integrated into larger devices by a manufacturer who does not want to deal with various details of the laser diodes.
There are also laser pointers, which can be considered as laser diode modules with integrated batteries, normally used as hand-held devices.
Suppliers
The RP Photonics Buyer's Guide contains 105 suppliers for laser diode modules. Among them:
CNI Laser
CNI has developed compact laser diode modules with spot, line, cross or fiber-coupled output. Typical features are small size, high compatibility, cost-effectiveness and easy integration into instruments and OEM equipments. Many output wavelengths are offered.
Bright Solutions
Bright Solutions offers the BDL and BFD – fiber-coupled diode laser modules:
- up to 200 W cw (or 400 W quasi-cw) in a 200-μm core fiber
- flat top beam profile
- integrated TE cooler, current and temperature controller
- optional fiber sensor
- pulsed models are available
They are used e.g. for pumping of solid-state and fiber lasers, material processing or illumination.
RPMC Lasers
Serving North America, RPMC Lasers offers one of the widest wavelength selections of laser diode modules available ranging from the UV through the LWIR. Our multimode and single-mode diode laser modules are available with output powers from 1 mW up to 5 W, with narrow linewidth options, in fiber-coupled, free-space, OEM, and turnkey configurations for a wide range of applications. Standard and custom options available. Let RPMC help you find the right laser today!
TOPTICA Photonics
TOPTICA offers various tunable diode laser modules. The combined spectral coverage is from 190 nm to 3500 nm, powers up to 4 W (TA), mode-hop-free tuning up to 110 nm (CTL).
TOPICA’s high-performance diode lasers are the ultimate choice when looking for a high-performance, ultra-reliable OEM diode laser system.
Sacher Lasertechnik
Sacher Lasertechnik offers industrial laser diode modules together with computer-controlled laser drivers. Emission wavelengths between 375 nm and 2800 nm are possible.
Advanced Photonic Sciences
APS’ new Cool Photons Module is a robust water-cooled assembly that allows easy setup and operation of high-power laser diodes, while also providing cooling and temperature monitoring. Compatible diodes can be found on APS website under high power visible laser diodes.
AeroDIODE
SHIPS TODAY: AeroDIODE offers fiber-coupled laser diodes as turn-key modules emitting between 520 nm and 1650 nm as stock items or associated with a CW or pulsed laser diode driver. They are compatible with our high speed nanosecond pulsed drivers or high power CW drivers with air cooling for the multimode high power laser diode versions.
The single mode laser diodes (either Fabry–Pérot or DFB laser diode) can reach high power in nanosecond pulse regime up to 500 mW. These turn-key diode & driver solutions are optimized for single-shot to CW performances with pulse width lengths down to 1 ns. The laser diode precision pulses are generated internally by an on-board pulse generator, or on demand from an external TTL signal. Many multimode versions are available with CW emission up to 300 W in a 200-µm core multimode fiber or up to 250 W in a 135-µm core fiber or 160 W in a 105 µm core fiber.
See also our tutorial on fiber-coupled laser diodes.
QPC Lasers
QPC Lasers manufactures fiber-coupled diode laser modules with the highest powers and brightness in the industry at wavelengths ranging from 780 to 2000 nm.
Products range from sub-watt single-mode PM fiber coupled diodes for LIDAR and communications to multi-mode fiber-coupled modules with outputs in the hundreds of watts for medical, materials processing and pumping applications. Optional features include Brightlock monolithically spectrally stabilized diodes for unmatched linewidth and spectral control.
AMS Technologies
AMS Technologies is a leading supplier of laser diode modules for a wide variety of wavelengths and optical output powers:
- fiber pigtailed laser diode (LD) modules
- fiber-coupled single emitter LD modules
- compact fiber-coupled LD modules, built-in LD driver electronics and TEC cooler
- free space LD modules in miniature and larger form factor, built-in LD driver and TEC cooler
- ultra-stable LD modules, fiber-coupled or free space
- dual- and triple-wavelength combiners, also with visible RGB wavelengths
- fiber optic multi-wavelength LD modules with two or up to four temperature-controlled LDs
- fiber-coupled multi-single emitter LD modules
- fiber-coupled LD modules with single/multiple LD bars and output power ranges of ≤40 W, 25–120 W or 40–350 W
CSRayzer Optical Technology
CSRayzer offers a wide range of diode laser modules, containing diode lasers or diode-pumped lasers with fiber pigtail or free-space output.
Lumibird
Lumibird manufactures a wide range of laser diodes and laser diode modules. Our offering includes QCW diode stacks, CW laser diode modules, fiber coupled QCW diode stacks, short pulse laser diode illuminators, as well as high brightness diode source, IALDA, and pulsed power supply drivers for QCW diodes.
Edmund Optics
Edmund Optics offers a wide range of diode laser modules, containing diode lasers or diode-pumped solid-state lasers.
Focuslight Technologies
Focuslight Technologies produces a wide range of high power diode lasers, including packaged lasers (laser diode modules). Free-space emitting packaged diode stacks are available, also fiber-coupled modules, based on diode bars or on single emitters.
There are also specialized laser diode modules for medical and aesthetic applications like fat reduction and laser hair removal.
Schäfter + Kirchhoff
Schäfter+Kirchhoff offer various laser line generators, laser focus generators or laser diode collimators. You can select them easily using our product configurator.
HÜBNER Photonics
HÜBNER Photonics offer diode laser modules with fully integrated electronics, allowing for rapid power modulation (rise time <2.5 ns). They are available with emission wavelengths between 375 nm and 975 nm, free-space or fiber coupled output, and output powers between 50 mW and 400 mW.
Sheaumann Laser
Sheaumann Laser offers various kinds of diode laser modules. The SheauPac Signature Package with its proprietary design withstands extreme temperature and vibration conditions as often encountered in military, industrial and space applications. The 2-pin package lasers have hermetically sealed fiber-coupled packages. There are also various butterfly (7-pin and 14-pin) packages available, and our High Heat Load (HHL) packages.
Frankfurt Laser Company
Laser diode modules from Frankfurt Laser Company are easy to use plug-and-play laser systems suitable for a wide range of military, industrial and medical applications.
Suited for pointing and target designation, spectroscopy, measurement equipment, laser display, printing, biomedical, patient positioning, material processing, laser show, alignment and positioning of materials including garments, cloth, paper, wood, stone and metal.
Integrated Optics
There are more than 150 CW laser configurations in the MatchBox product family. It contains wide selection of diode lasers, ranging from 375 nm to 1550 nm, coming in regular or narrow spectrum versions, having multiple options of output: MM/SM/PM fiber coupled, free space or SMA port. Fiber coupling is inside the sealed housing and temperature stabilized. MatchBox lasers have a very compact housing, which contains optical layout, driver electronics, that can enable up to 10 MHz externally triggered modulation and TEC temperature control. MatchBox lasers can also combine up to 4 different diode wavelengths in one single housing with the same record-small footprint of 30 × 50 × 18 mm.
See also: laser diodes, laser pointers, fiber-coupled diode lasers, OEM laser modules
Questions and Comments from Users
Here you can submit questions and comments. As far as they get accepted by the author, they will appear above this paragraph together with the author’s answer. The author will decide on acceptance based on certain criteria. Essentially, the issue must be of sufficiently broad interest.
Please do not enter personal data here; we would otherwise delete it soon. (See also our privacy declaration.) If you wish to receive personal feedback or consultancy from the author, please contact him, e.g. via e-mail.
By submitting the information, you give your consent to the potential publication of your inputs on our website according to our rules. (If you later retract your consent, we will delete those inputs.) As your inputs are first reviewed by the author, they may be published with some delay.
Share this with your friends and colleagues, e.g. via social media:
These sharing buttons are implemented in a privacy-friendly way!