Solid laser excitation source
Solid-state lasers use light as an excitation source. Commonly used pulse excitation sources are charged xenon flash; continuous excitation sources include krypton arc lamp, iodine tungsten lamps, potassium xenon lamps and so on. In small long-life lasers, semiconductor light-emitting diodes or sunlight can be used as the excitation source. Some new solid-state lasers are also laser-excited.
Solid laser characteristics
Solid-state lasers can be used as high-energy and high-power coherent sources. Ruby pulsed lasers have an output energy of up to kilojoules. The maximum pulse power of the q-tuned and multistage amplifying neodymium glass laser system is up to 10 watts. The output power of yttrium aluminum garnet continuous laser is up to 100 watts, and multi-stage serial connection can reach kilowatt.
Solid-state lasers use Q-switching technology (see light modulation) to obtain short pulses in the order of nanoseconds to hundred nanoseconds, and ultra-short pulses of the order of picoseconds to hundred picoseconds can be obtained using mode-locking techniques.
The output of the general solid state laser is multimode due to optical inhomogeneity of the working material. If a working material with good optical uniformity and a technical measure such as a well-designed cavity are selected, a fundamental transverse mode (TEM00) laser with a beam divergence angle close to the diffraction limit can be obtained, and a single longitudinal mode laser can also be obtained.
The trend of solid-state lasers is the diversification of materials and devices, including the search for new working substances that can be tuned for new and working wavelengths, improving the conversion efficiency of lasers, increasing output power, improving beam quality, compressing pulse widths, improving reliability and prolonging working life.
