The power of this kind of green laser pointer is from 175mW to 200mW

The power of this kind of green laser pointer is from 175mW to 200mW
A DC term and the second harmonic, DC known as optical rectification. When the laser incident at an angle to the frequency-doubling crystal, the second harmonic in the crystal to produce frequency doubling the angle of incidence of light is called the matching angle. The intensity ratio of second harmonic conversion efficiency for second harmonic and the fundamental frequency, and nonlinear optical theory can be proved: where L is the crystal length and frequency of the light output of the second harmonic light, respectively, for the incident base , respectively for the fundamental frequency of the light and the amount of frequency doubling of light propagation vector. In the case of normal dispersion, the refractive index of the second harmonic is always greater than the refractive index of the fundamental frequency of light. This kind of  green laser pointer  is called the wireless presenter laser pointer.
Therefore, the phase mismatch, the birefringence of different refractive index of the crystal O light and e light and e light refractive index change with the change of the angle between the direction of propagation and the optical axis, we can use O light and a birefringent crystal normal dispersion of the refractive index difference between the e light to compensate for media of different wavelengths of light to achieve phase matching. The 808LD obtained by the experimental use of 808nm near infrared light, 1064nm near infrared laser using Nd: YVO4 crystal, then KTP crystal for intracavity frequency doubling the 532nm green laser. The experimental setup shown in figure VI. End-pumped in order to improve the efficiency of the spatial coupling, with a focal length of 5mm gradient. It equals to pressing the page up or page down key on the keyboard of the computer when using green laser pointer .
Refractive lens collection the 808LD beam is focused into a thin beam of 0.1 μm, so that the beam waist in of Nd: YVO4 crystal internal Length 1mm adulterated concentration 3at% axial cutting of Nd: YVO 4 crystal as the working substance, the incident light to the internal of about 95% is absorbed. Ⅱ phase matching KTP crystal as the frequency doubling crystal, at the same time it's through glossy 1064nm, 532nm high permeability. The cavity is concave, after chamber piece heat bending; before the chamber piece with K9 glass, R is 50mm higher than 808.5 trans, 1064 semi-inverse. For directions using 632.8nm He-Ne laser light source. Of WGL-2-type semiconductor pump laser principle demonstration instrument, SGL-II-type semiconductor laser tunable power of SGN-II optical power tester.