Through simulating the process of image construction we propose a new image degradation model in this paper, and mutual effect from adjacent pixels, not well-proportioned illumination, as well as the decline of medium transfer ratio are taken into account in the new model. Based on the research on human visual system, including contrast sensitivity, bright- ness adapting ability and side restraint, a vision adaptability solution for the model is proposed. There three processes are included in the solution: a de-convolution process to eliminate the adjacent pixels' mutual effect and provide people with more details; an intensity adjustment process to provide the cone cells with a suitable working condition (the intensity adjustment function is proposed according to cone cells brightness adapting ability) and the contrast upgrade process proposed through simulating the side constraint thesis. Compared with some existing image enhancement algorithms, it can be found in the experimental results that the applications of the proposed algorithm yield some promising results in getting more details, upgrading the contrast, and increasing the visual pleasing characters.