Advantages and Disadvantages of Semiconductor Lasers

Semiconductor lasers, also known as laser diodes (Laser Diode, LD), are one of the latest achievements in the development of semiconductor physics in the 1980s. The advantages of semiconductor lasers are small size, light weight, good reliability, long service life and low power consumption. In addition, the semiconductor laser adopts a low-voltage constant-current power supply mode, which has a low power failure rate, safe use, and low maintenance costs. At present, the number of semiconductor lasers used ranks first among all lasers, and some important application fields have been gradually replaced by semiconductor lasers. In addition, there are many types of semiconductor lasers, including infrared and red light with longer wavelengths, and green and blue light with shorter wavelengths. These advantages can be used to expand the measurement range of laser particle size analyzers and improve measurement accuracy.

The performance of early semiconductor lasers is greatly affected by temperature, and the divergence angle of the beam is also large (generally between a few degrees and 20 degrees), so the performance in terms of directionality, monochromaticity and coherence is not ideal. However, with the rapid development of science and technology, the performance of semiconductor lasers has reached a very high level, and the beam quality has also been greatly improved. Therefore, most brands of laser particle size analyzers in the world use semiconductor lasers as light sources.

When the semiconductor laser is used as the light source of the laser particle size analyzer, constant current and constant temperature measures must be adopted in the control circuit to ensure the stability of the output power.