The Multi-Channel Laser Focusing Transceiver System and Analysis of the Image Quality

摘要

This paper has investigated and designed a multi-channel laser focusing transceiver system based on the combination of the laser technology, the space technology and the modern photoelectric detection technology which has the feather of wide wave band, non-chromatic aberration and high quality of image quality etc. The system could be synchronized and can change the distance of detection in a particular direction and obtain the image of atmospheric echo signals at different distances. In this paper, we established a multi-channel and variable range laser focusing transceiver system that consists of a single-channel laser focusing transmitter system and a dual-channel receiving telescope system. The three channels of the system depend on the same reference axis. We propose a new method that is capable to improve the laser focusing transceiver system performance. The method is implemented by using parabolic reflector design in the primary and secondary mirror of the variable range laser focusing transmitter system, dual-channel off-axis design in the receiver system and simultaneous imaging design in the different regions of the same CCD target surface of the subsequent imaging system. The detection by two channels using off-axis design would be convenient for computing follow up information. On the base of theoretical basis of the reflective double mirror system and the theory Gaussian beam propagation, this paper calculates the actual converging sot size of the transmitter system and analyzes the wavefront aberration the defocus incidence. The oblique incidence will introduce the certain astigmatism and a small amount of coma, and the defocus incidence will produce the certain coma and a small amount of spherical aberration and astigmatism. Finally, an experimental multi-channel laser focusing transceiver system was established and the image quality of the transceiver system on the base of wavefront aberrations, the spot diagram and the MTF curve of some fields is analyzed. Through a lot of experiments, the actual test results are obtained. The wavefront aberrations RMS of the system are 0.079λ, 0.0822λ, and 0.0808λ, respectively. The actual test results of the system have met the design requirements which must be better than λ/12=0. 0833.