Optical system integration of near infrared laser altimeter

The method for designing beam expander of near infrared laser altimeter is discussed in the paper. By designing the beam expander with 632.8nm and 1064nm respectively and integrating it with 632.8nm design but compensating the chromatic aberration with 1064nm design with gasket and finally testing the result with 1064nm laser, the beam expander with requirement magnification is integrated. With a simulate detector and a Continuous-Wave (CW) 1064nm laser, an infinite light with divergence of the Field-of-View (FOV) of the telescope is produced. By acquiring the image of this infinite lignt and the laser transmitter at a 4m collimator's focal plane using a CCD camera and adjusting the relative azimuth and pitching of the transmitter and receiver, the alignment of the two subsystems is finished with the decentration less than 5%.