Catadioptric expander for laser beam

Improving the accuracy of range acquisition to the spacecraft with the help of laser location becomes possible when using the dispersion method in the determination of the average atmospheric index of refraction. The purpose of the research was to calculate the expander of the laser beam working at the same time for a wide range of wavelengths without any additional refocusing. The authors give their variant of the calculation of the optical system of the expander of laser beam for the satellite laser ranging station in the optical and near infrared wavelengths. A laser beam expander is a catadioptric system with the entrance pupil diameter about 42 mm and approximately 300 mm outlet. The collimation of the laser beam takes place in the expander without any additional refocusing for wavelengths from 435 to 2098 nm with a sevenfold increase. The beam divergences for monochromatic radiation are defined as well. In the presented optical system Coudě focus is used which allows using the equipment installed permanently. When calculating the optical system, the radii of curvature of all spherical surfaces are recommended by All Union State Standard 1807-75 which reduces the cost of manufacturing technology. In the reverse ray path the expander can be the feeding optics of object tracking lens in the optical range. To avoid vignetting when using the expander as feeding optics of CCD-camera for the satellite tracking (in the reverse ray path), the light lens diameters are calculated. The expander of laser beam may be using for satellite laser ranging station and laser radars on Earth surface.