5 Types of Lasers & their applications

Introduction : Laser is the short form of “Light Amplification by Stimulated Emission of Radiation”. Laser devices generate highly collimated, monochromatic and coherent beams of light by stimulating excited atoms within a gain medium. There are different types based on medium such as solid state, gas, fiber, liquid, semiconductor etc. The parameters such as wavelength, power and operational mode of lasers determine its suitability for specific applications.

Laser Types

1. Solid-State Laser: These lasers emit infrared light, typically at a wavelength of 1.064 micrometers. It uses solid gain medium typically crystal or glass doped with rare earth ions such as neodymium, erbium or titanium-sapphire. It can operate in CW mode or pulsed modes.

   • Advantages : High beam quality, high peak power, robustness etc.
   • Applications : LiDAR, Material processing, Medical surgeries, scientific research etc.

2. Gas Laser: It employs gaseous medium such as CO2, He-Ne or argon. It is excited primarily via electrical discharge to produce laser light. Gas lasers often have a primary output of visible red light. CO2 gas lasers emit energy in the far-infrared region, specifically at a wavelength of 10.6 micrometers.

   • Applications : He-Ne lasers are used in alignment tools and barcode scanning. CO2 lasers are used in industrial cutting and welding.

3. Excimer Laser: Excimer lasers produce light in the ultraviolet range perfect for medical procedures such as LASIK.They are class of pulsed gas lasers which use mixture of noble gas and halogen to form short lived excited dimers.

   • Applications : Micromachining, semiconductor photolithography, LASIK etc.

4. Dye Laser: Liquid based dye lasers use an organic dye solution as the gain medium and are optically pumped. This type of laser is tunable over a broad range of wavelengths, making it versatile for different applications.

   • Applications: spectroscopy, biomedical research and laser based diagnostics

5. Semiconductor Laser: Semiconductor lasers, optimized from PN-junction diodes, emit light when current is applied. Semiconductor lasers are very small and use low power.

   • Applications: They are commonly used as writing sources in devices like laser printers, CD players, and DVD players.

Conclusion : Each laser type leverages a distinct gain medium and operational mechanism to meet specialized needs. From the precision cutting of industrial materials using CO₂ lasers to tunable spectroscopy with dye lasers and from compact laser diodes in everyday electronics to ultrashort UV pulses in excimer systems, laser technology spans an exceptional breadth of applications. As innovations in materials, pulse shaping, and power scaling accelerate, the future promises even greater laser capabilities.