You can choose the best infrared (IR) lasers by first determining the intended use of the lasers. The desired wavelength and beam diameter of the IR lasers will need to be considered as well as if a continuous wave or pulse type laser is preferred. Additional factors to take into account include the cost of the lasers and what additional components may be required to assure continuous and desired functionality.
Applications for IR lasers vary widely and include military, medical, and scientific applications. Commercial and industrial applications are also prevalent. Each application within each industry will necessarily require different parameters for determining the best-suited laser depending on individual needs and specific uses.
Industrial applications such as materials processing predominately will utilize a gas laser. Gas IR lasers, using carbon dioxide, are very efficient and lose a minimal amount of power during operation. These are generally best for cutting and welding purposes.
Solid-state IR lasers are dominant in the medical industry and can be found in many other additional applications. Surgical procedures, laser targeting, and periodontal scaling are a few of the standard uses for the solid-state laser. This type of laser is also used in photo processing and semiconductor inspection.
Semiconductor lasers or diode lasers are becoming more prevalent and are smaller and more efficient than their predecessors. This type of laser may be a direct diode laser or a diode pumped solid state (DPSS) laser. Each type is somewhat better suited for different purposes. DPSS lasers are generally more sensitive to heat and have a smaller range of operation than the diode lasers. Applications requiring high beam quality often utilize DPSS lasers.
The semiconductor IR lasers will most often be the best choice for smaller applications, and DPSS lasers provide the power and wavelength desired by a number of implementations. Some of the primary applications for this type of laser include IR illuminators for night photography, night-vision scopes often used for firearms, and various human-computer interaction projects, such as blob detection.
Builders of laser-driven devices will also want to ensure that power and cooling will not be issues when choosing the appropriate IR lasers. Inappropriate power voltage or fluctuations in current can destroy or dramatically decrease the longevity of a laser. The power of the laser itself is relevant, as this is paramount in determining the penetration, distance, and duration of the laser beam. Pay close attention to the variations in peak and average power when investigating IR lasers.