High-power laser system has a requirement for the medium and low spatial wavefront errors of the transmitted wavefront of the spatial filter, which is a spherical lens with long focal length (> 10 m) and large aperture (> 400×400 (mm)). Two interferometric methods are analyzed and compared for testing the medium and low spatial wavefront errors of the long focal length lens with an instantaneous interferometer, using large -aperture plane mirror and concave mirror as retroflectors, respectively. The two kinds of beam path -arrangements are designed using ray tracing method. Wavefront aberration and modulation transfer function are used as merit functions. The reason for their different ability to test the wavefront is also analyzed. To evaluate the -feasibility of test methods, tolerances analyses are performed to determine the tolerances demanding the fabrication and assembly of each optical element. It is proved that a relatively short optical path with a large aperture concave mirror is satisfied for testing the medium and low spatial wavefront errors of the transmitted wavefront of the spatial filter.

A portable near-infrared (NIR) spectroscopy analyzer is developed for rice wine analysis. The analyzer is composed of a lamphouse, a temperature-controlled sample chamber, a mini-spectrometer, and a control unit. The mini-spectrometer is based on the crossed Czerny-Turner structure grating platform and a linear InGaAs array detector with spectrum range of 1100?2500 nm and spectral resolution of 1.5-12 nm full-width at half-maximum (FWHM). The control software written in VC++ consists of three parts: the spectra acquisition, the model establishment, and the sample analysis. The calibration models of determination of alcohol and nonsugar solids in rice wine are established with 54 samples. After calibration, the portable analyzer is used for real-time analysis of the rice wine sample.