What is a blue laser diode

- 2021-08-26-

A blue laser diode is a semiconductor laser that can generate a concentrated photon beam with a wavelength of about 400 to 500 nanometers (the visible electromagnetic spectrum region considered blue or violet by the human eye). Blue laser diodes are more difficult to manufacture than many other types of lasers, especially at high power levels, but the short wavelength of blue light allows for higher accuracy. Blue laser diodes are now used in laser pointers, video projectors, and devices that use high-definition optical discs, the most prominent being the Blu-ray format.
Blue laser diodes can be used for laser pointers.
Like all laser diodes, the light of the blue laser diode is produced by pumping energy into the semiconductor. This is achieved by current, which distinguishes semiconductor lasers from optically pumped semiconductor lasers that use light. This causes the electrons in the semiconductor material to rise briefly to energy levels. When the electron returns to its original energy level again, the lost energy will be released in the form of photons to produce light. The light is then collimated with a laser lens, focusing the resulting photons in one direction, producing a concentrated beam of light.
The color of the laser depends on the wavelength of the photon, and the wavelength of the photon depends on the properties of the atoms or molecules that make up the gain medium. The commonly used gain medium material for most blue laser diodes is gallium nitride (GaN), which is a crystalline semiconductor. Indium nitride (InN) and indium nitride (InN) are alloys of the two. The blue laser diode is the basis of a variety of optical data storage formats, such as Blu-ray, China Blue High Definition and HD DVD. All optical discs, such as CD and DVD, store information in the form of tiny dents. As the player rotates inside, the laser will read these dents. CDs and DVDs use a laser that produces red light, which has a longer wavelength than blue light, so it needs a wider dent on the disc to read it correctly. The shorter wavelength of blue light allows the blue laser to accurately read smaller features on the disc, which means more dents, which can contain more data on the same size disc. This allows a disk designed to be read by a blue laser diode, which can fit approximately 25G of data into a single disk layer, which is more than five times the capacity of a DVD.