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For an echelle spectrometer based on a digital micromirror device and photomultiplier, a lens group is placed in front of the digital micromirror device and used to converge the two-dimensional spectrum and correct aberration. The matching spectral reduction model is deduced by establishing the mathematical models of the imaging mirror and lens group. According to the known wavelength and corresponding coordinates, the refractive index of the prism is fitted, and the spectrum is divided into three parts to calibrate. Experimental results of a mercury lamp show that the maximum deviations of x and y coordinates are 3.4 pixels and 2.3 pixels in the corrected spectral reduction model. The deviations are in the range of the errors permitted, which means the extraction of order and wavelength satisfy the requirement of the spectrometer.

The traditional window of high-speed aircraft is hemispherical, and the aberration produced by such a window is constant. However, the hemispherical window is difficult to meet the requirements of a high speed flight of aircraft. Aspheric windows are usually used to replace hemispherical windows to increase the aerodynamic performance. However, the aspheric window will introduce dynamic aberrations that fluctuate with the change of scanning field-of-view (FOV), which becomes the key issue of the development of optoelectronic imaging systems for high-speed aircraft. For the ellipsoidal window optical system with scanning FOV of ±60°, an aberration correction method in large FOV combined with the static correction and non-wavefront-sensor adaptive optical correction is studied. In the initial optical structure design, the types of system aberration are reduced and the fifth-order Zernike aberration is eliminated during initial aberration correction, thus, the number of the subsequent adaptive optimization control variables is reduced. According to the characteristics of the deformable mirror, the driving voltage of the driver is generally taken as a variable of the genetic algorithm. However, when the deformable mirror used has many units, too many variables will directly lead the optimization speed of the algorithm to greatly decrease. So, according to the aberration characteristics of the ellipsoidal optical window, using the conversion matrix between the Zernike polynomial coefficients and the voltages of the deformable mirror driver, the optimization variable is reduced from 140 driver voltages to 2−9 Zernike stripe polynomial coefficients in number. Finally, the genetic algorithm based on Zernike model is used to control the shape of the deformable mirror and correct the residual aberration. Taking 2−9 Zernike mode coefficients, 2−16 Zernike mode coefficients and 140 driver voltages as the variables of genetic algorithm respectively, the optimization generations of genetic algorithm under different variables are obtained. The simulation results show that the optimization speed of each typical scanning field of view is increased more than 95% by changing the variable from 140 driver voltages to 2−9 Zernike mode coefficients, and the imaging quality is close to the diffraction limit. This optimization method can not only correct the aberrations caused by the special-shaped optical window, but also compensate for the error caused by processing and aligning the optical system.

Polarization imaging technology has shown great advantages in military reconnaissance, vegetation remote sensing and aerosol detection, and the study of the properties of the polarized light transmission can better promote the development of technology. In this paper, according to the characteristics of multi-spectral polarized light transmission in smog environment, an experimental test device of multiple spectral bands of visible light is built in the smog simulation environment, experiments show that when the wavelength changes between 0.5–0.73um, the polarized light of the circularly polarized light is larger than that of the linearly polarized light, and the linearly polarized light exhibits better polarization characteristics in the other wavelengths of the visible light.

The efficiency of Gaussian-wave light propagating in weak atmospheric turbulence coupled into a single model fiber is studied, and an approximation to the original mutual coherence function (MCF) in the coupling-efficiency expression is given to simplify the complexity of the efficiency calculation. The influence of the transmitting beam and turbulence parameters on the Gaussian-beam coupling-efficiency has also been evaluated. The numerical results show that the relative error of the expression with the approximate MCF referenced to the original Gaussian-wave fiber coupling efficiency representation is not more than 3.69%. It is anticipated that this work will be helpful in estimating the receiving performance and optimizing effective beam parameters at the transmitter in the design of a free-space laser communication system.