In this paper, we propose a new spatial encoding method that integrates the random binary pattern and the improved phase-difference-matching method to acquire a dense and precise depth map. The adopted binary pattern can simplify pattern projecting devices compared with the patterns that use color. The density of speckles in the pattern is periodic and the positions of them are random. Based on these two properties, we propose an improved phase-difference corresponding method, which is divided into two steps: the coarse matching step to estimate the approximate coordinates of pixels in the pattern via analyzing the phase values of the image, and the fine matching step to compensate errors of the coarse matching results and to achieve subpixel accuracy. This matching method does not require an extra optimization method with high computational complexity. In the experiment, we show the effectiveness of the proposed method. We also evaluate this method in actual experiments. The results show that this method has advantages over the time-of-flight camera and Kinect, particularly in terms of precision.