Laser rods are cylindrical laser crystals or laser glasses that serve as the core component of a laser. They act as the gain medium, absorbing pump light and converting it into laser output through stimulated emission.
Laser rods
2. Working Principle
When the laser rod is excited by a pump light source (such as a flash lamp or diode laser), electrons transition to a higher energy level. As these electrons return to a lower energy level, they emit photons. These photons stimulate more electrons, producing a coherent photon group with the same phase and direction, forming the laser.
YAG Laser Optically Pumped by Xenon or Krypton Lamp Application
3. Key Parameters
Laser Wavelength: The wavelength of the light emitted by the laser rod, determining its application field. For example, the wavelength of an Nd laser rod is 1064 nm.
Output Power: The power of the laser output from the laser rod, usually measured in watts (W) or milliwatts (mW).
Pulse Width: The duration of the laser pulse, usually measured in nanoseconds (ns), picoseconds (ps), or femtoseconds (fs).
Laser Mode: The transverse and longitudinal modes of the laser beam, including fundamental mode (TEM00) and multimode (Multimode).
Surface Finish:High-quality surface finish (with precise orientation, high flatness, good scratch/dig specifications) is generally required for the two end faces, through which the laser beam is usually sent. The optical quality of the outer surface (mantle) is usually much less critical, although it often serves for the entry of pump light (for side-pumped lasers). That surface is also used for cooling.
Poshing and Coatings:The quality of the interface polish and the coatings can have a substantial impact on the threshold intensity (or fluence) for laser-induced damage. That damage threshold is relevant for pulsed lasers, particularly those with high peak power.
4. Applications
Industrial Wavelength: Laser rods are used for cutting, welding, marking, etc. For example, Nd lasers are widely used in processing both metals and non-metals.
Medical : Laser rods are used for laser surgery, laser therapy, etc. For example, Er lasers are commonly used in skin resurfacing and dental surgery.
Scientific Research: Laser rods are used for spectroscopy, optical experiments, etc. For example, Ti3+ lasers are used in femtosecond spectroscopy and studies of ultrafast phenomena.
