The micro-vision images captured by the CCD camera typically show low gray value, non-uniform illumination, large dynamic range, poor contrast and missed or unrecognized fine structure due to the coaxial light source and optical diffraction in micro-vision system. Based on the raised cosine and variable gain sub-band decomposition algorithm, a micro-vision image adaptive enhancement method was developed to improve the image quality in this work. First, on the basis of image characteristic, the original micro-vision image was enhanced by using adaptive Log gain function to improve the contrast between minutiae and background which located in bright or dark regions. Then, the fast illumination estimation was carried out in terms of the adaptive cosine convolution. After that, the independent spectral sub-bands of the image in each channel were obtained through the adaptive variable gain sub-band decomposition algorithm. The ultimately enhanced image was generated after the implement of intensity correction, image fusion and color restoration. The algorithm had been successfully applied to a micro displacement measurement system and the relative error was less than 20%. Moreover, extended the algorithm to ordinary image processing can improve the contrast and minutiae. The relative increasing rates of the average quality of three experiments were 81.46%, 71.18% and 93.75%, respectively; and the average consuming time were 3.86 s, 0.24 s, and 1.27 s, respectively.