The high resolving power camera was often used to improve the precision of measuring system although its price is high, because the accuracy of image measure was limited by the pixel resolving ability of camera. A method of one dimension gray level quadrature sub-pixel to detect edge was presented. This method was applied to measure the displacement of measuring head on 3-coordinate measuring machine. The data of test was shown that this system can distinguish displacement 0.001mm. it is higher accuracy than pixel level. So this method is convenient and fast , fit to track and measure the moving object. It is obvious that this method can save the cost of hardware.

Compared with normal reflecting scanning transform Spectrometry, cube-based Spectrometr is a key component in the time-based modulation interference spectrometer, it have more compact structure ,using less accessory , easy to fix up , more steadily and more practicality . Calculations on optical path difference (OPD) of spectrometry play an important role in analyzing and improving of the structure. Following the law of Malus and the geometrical relationship of model, get the formula of OPD and the affective factors .The calculation results demonstrate that OPD is closely related to the tilted angel of rotating reflector , the size of cube reflector and the refractive index of reflector. And this kind of spectrometry has the character of high resolution, especial in some spectrum.