Light detection and ranging (LiDAR) return signal generation technology applied in the LiDAR indoor test and simulation is significant to design, develop, test, and validate a LiDAR’s capability and performance. To generate a target’s information carried by the return signal, the dimensional decomposition and equivalent generation method of the LiDAR return signal are proposed. The target four-dimensional (4D) information is decomposed into one-dimensional (1D) intensity information, 1D range information, and two-dimensional (2D) angle–angle spatial information. The 1D intensity information is simulated by the absorption of prism pairs, while the 1D range information is simulated by the combination of electrical and optical time delay. The 2D angle–angle spatial information is implemented by the stack of segmented digital mirror array device slice images in sequence. Moreover, a LiDAR return scene projector (LRSP) prototype is developed and its performance is measured. The results show that its energy dynamic range is 51.25 dB. The distance simulation range is 240.15 m to 22.5 km (1.601 to 150  μs). The simulation accuracy of the target’s depth is <9  cm (0.6 ns). The spatial resolution of 64  ×  64  pixels is verified by vertical and horizontal line pairs test. Because the LRSP has 12 image slices, its resolution is 64  ×  64  ×  12  pixels in three-dimensional (3D) space. Finally, the prototype is demonstrated by reconstructing a staircase. The energy dynamic and 2D angle-angle spatial resolution are improved significantly compared with the existing LRSPs.