Abstract

355 nm ultraviolet solid-state lasers are commonly used in micromachining, photolithography and precision drilling and other fields. Its high energy density and small spot size enable high-precision and high-quality processing results. In addition, 355 nm ultraviolet solid-state lasers are also widely used in scientific research. For example, it can be used in fields such as spectroscopic analysis, Raman spectroscopy, protein structure research, and biological microscopic imaging

Gain medium: Nd:YVO₄ laser crystals

Nd:YVO₄ crystal has a high absorption cross-section, which can effectively absorb the excitation light of the laser diode. Nd:YVO₄ crystal helps to achieve high-efficiency laser emission and improve the efficiency of the laser

Resonant Cavity

An optical resonator is built around the Nd:YVO4 crystals, including high reflection mirrors and output coupling mirrors. The high reflection mirror has high reflectivity, realizes reflection at a wavelength of 355nm, and repeatedly propagates the beam through the Nd:YVO4 crystal to increase the gain.

M1 is a plano-concave lens, one side is coated with a total reflection film with a wavelength of 1064nm, and the other side has a unique high-transmission film with a wavelength of 808nm.

M2 is a plane lenses, one side is coated with a total reflection film with a wavelength of 532nm, and the other side is unique with a high-transmission film with a wavelength of 1064nm

Q-switch Crystals

LiNbO₃ crystals is used as a Q-switched switch to adjust the output pulse width and repetition rate of the laser.

Frequency conversion

Type I LBO crystals intracavity frequency doubling and type II LBO crystal intracavity sum frequency to obtain 355nm ultraviolet laser. Type I LBO crystal intracavity frequency doubling and type I BBO crystal extracavity quadruple frequency to obtain 266nm ultraviolet laser.