应用天文研究组知识库

Strong background noise will greatly reduce the probability of ranging success in lunar laser ranging and space target daytime laser ranging. The 1. 2m Telescope laser ranging system of Yunnan Observatory uses an adjustable field diaphragm in the receiving light path to reduce the background noise by changing its aperture. However, because of velocity abberation, when the receiving field view is reduced to a few arcsecond, the echo will be blocked by the aperture and the detector will not receive the echo photon. In order to solve this problem, a method of adding a two-dimensional tip/tilt mirror in front of the field diaphragm is proposed. Tip/tilt mirror can let the deviated echo be received by the detector. The echo deviating angles is measured by observing some high-orbit satellites and GEO satellites. And the effect of using the tip/tilt mirror to correct the deviation angles is simulated and analyzed based on 1. 2m telescope. The results show at this method can quickly and accurately correct the echo deviating angles in small field of view laser ranging, and can provide support for lunar laser ranging at full moon and space targets daytime laser ranging.