Optical measurement instrument and method for atmospheric coherent length

Abstract

The invention discloses an optical measurement instrument and method for atmospheric coherent length. The optical measurement instrument for atmospheric coherent length comprises an He-Ne laser emission unit (1), a laser receiving and photovoltaic conversion unit (2), a data acquisition unit (3) and a data processing and analyzing unit (4), wherein the laser emission unit (1) comprises a He-Ne laser device 11 for emitting laser and a beam expanding device 12; and after a laser beam emitted by the He-Ne laser device 11 is expanded by the beam expanding device 12, the laser beam is transmitted by atmosphere turbulence and then vertically enters the laser receiving and photovoltaic conversion unit (2). The invention also discloses a measurement method for the optical measurement instrument. The optical measurement instrument has the advantages that influence the inner and outer scale of the atmosphere turbulence on the measurement method can be overcome very well, and the measurement result is more reasonable. The adopted position sensitive detector can directly give a position signal and a relative optical intensity signal, the memory is saved, and meanwhile, the requirement on the computer is lowered.

Description

technical field [0001] The invention belongs to an optical measuring instrument and method for atmospheric coherence length, in particular to an instrument for measuring atmospheric coherence length on a near-surface optical transmission path. It is suitable for atmospheric science research, as well as astronomy, atmospheric optics, military and other fields. Background technique [0002] Due to the influence of atmospheric turbulence, light intensity fluctuations and phase fluctuations will occur when light propagates in the atmosphere. For imaging systems, this will lead to blurred images. In astronomy, the fluctuation of the light wavefront caused by atmospheric turbulence makes the actual resolution of the receiving optical telescope closely related to the atmospheric coherence length. With the development of modern optical technologies such as space target monitoring, adaptive optics, and laser communication, it is required to obtain the atmospheric coherence length on...

AI Technical Summary

Problems solved by technology

This method is to invert the value of the atmospheric coherence length by using the distance variance of the center of mass of a light spot imaged by a light source at two positions that are not far apart. Measuring errors caused by factors such as mechanical vibration and the jitter of the light source itself when deriving atmospheric coherence length values, but in practical applications, imaging devices often use optoelectronic products such as CCD or ICCD. The use of these devices increases the cost and also limits the measurement

If the sampling rate is low, it will inevitably lead to the loss of the high-frequency characteristics of atmospheric turbulence. On the premise that the sampling number is required to meet the statistical law, the sampling time will be lengthened and the real-time performance will be reduced.

Moreover, such devices usually process the entire imaging picture, which requires a large amount of memory resources, which is not conducive to engineering integration and real-time measurement

Images