The invention relates to a red and 
green laser based on a 
laser crystal, a frequency doubling 
crystal and a self-frequency-doubling 
crystal. The red and 
green laser comprises a dual-
wavelength pumping source, a focusing lens, the 
laser crystal, the frequency doubling crystal and the self-frequency-doubling crystal, wherein the dual-
wavelength pumping source, the focusing lens, the 
laser crystal, the frequency doubling crystal and the self-frequency-doubling crystal are sequentially arranged along an 
optical path. The light transmitting surface of the laser crystal, the light transmitting surface of the frequency doubling crystal and the light transmitting surface of the self-frequency-doubling crystal are plated with 
dielectric films, and the laser crystal, the frequency doubling crystal and the self-frequency-doubling crystal are sequentially combined together through the light transmitting surfaces. The laser crystal is a 
neodymium-doped 
yttrium vanadate crystal. The frequency doubling crystal is a 
potassium titanyl oxygenic 
phosphate crystal. The self-frequency-doubling crystal is a 
neodymium-doped 
yttrium calcium oxyborate crystal or a 
neodymium-doped 
gadolinium calcium oxyborate crystal, the self-frequency-doubling crystal is 
cut in the light transmitting direction, and the 
cutting direction is a self-frequency-doubling direction where 530 nm or 545 nm 
laser light is generated. The red and 
green laser is formed by gluing the dual-
wavelength pumping source, the laser crystal, the frequency doubling crystal and the self-frequency-doubling crystal and is compact in structure and good in stability; in the 
optical path, 
red laser light and 
green laser light are output respectively and do not interfere with each other, and switching is convenient.