Common Laser Types
This is Section 3.7 of the Laser Optics Resource Guide.
Lasers are often classified by the gain medium used for light amplification. Common gain media types are gas, semiconductor (diode), and solid state.
Gas lasers, such as helium neon (HeNe), are often used for metrology applications due to their high beam quality and long coherence length. Other types of gas lasers, such as carbon dioxide (CO2) lasers, are frequently used for materials processing because they can reach exceptionally high average powers.
Diode lasers contain a semiconductor p-n junction as the gain medium. They tend to have the highest power-to-cost ratio and benefit from high power conversion efficiency, high quantum efficiency, and a wide range of available wavelengths. Diode lasers are utilized in many applications including telecommunication, materials processing, bar code scanning, medical lasers, and LIDAR systems.
Solid state lasers utilize crystals or glass materials doped with transition metal or rare earth ions. They are often utilized for high power applications, such as material processing and medical lasers, because they can reach some of the highest peak powers out of all commercially available lasers.1 However, it is harder to cool solid state gain media, which limits repetition rate and average power.
Fiber lasers are a special type of solid state laser which use an optical fiber doped with rare earth ions as the gain medium. They are optimal for creating very fine features in highly precise machining and medical applications because they contain a high average power in a single optical mode with high beam quality.
Thin-disk lasers are another special type of solid state laser in which the gain medium is a very thin disk of solid material. They are a balance between fiber lasers and other solid state lasers in that they achieve a high peak power and gain while utilizing a geometry that makes them easier to cool, improving their repetition rate and average power. However, they require complex system designs and therefore cost more than other laser types.
Figure 1: Common commercial lasers with typical modes of operation and gain media 2, 3
Lasers from Edmund Optics®
Edmund Optics offers a wide range of laser sources as well as laser optics, safety equipment, and measurement devices.
1. Weber, Marvin J. Handbook of laser wavelengths. CRC Press, 1999. ISBN 978-0-8495-3508-2.
2. Paschotta, Rüdiger. Encyclopedia of Laser Physics and Technology, RP Photonics, October 2017, www.rp-photonics.com/encyclopedia.html.
3. Lasers and Their Uses Reference Wall Chart. Photonics Media, 2010
- Coherent® Laser Selection Guide
- Characteristics of 2µm Lasers
- Laser Resonator Modes
- Ultrafast Lasers – The Basic Principles of Ultrafast Coherence
- Quantum Cascade Lasers and Applications
- Gaussian Beam Propagation Application Note
- Gaussian Beams Calculator
- Beam Quality and Strehl Ratio Application Note
- Laser Optics Lab Video Series