1. A control method of a depth camera, the depth camera including alight source, a first image sensor unit and a second image sensor unit which are spaced apart from each other and which have overlapping field of view, and a processor which is connected electrically to the light source, the first image sensor unit and the second image sensor unit, the first image sensor unit detecting light in a first range of wavelengths, the second image sensor unit detecting light in the first range of wavelengths as well as light in a second range of wavelengths different from the first range of wavelengths, the light source emitting light in the second range of wavelengths, the control method comprising the steps of: controlling, by the processor, each of the first image sensor unit and the second image sensor unit to detect light in the first range of wavelengths for generation of a respective one of a first image by the first image sensor unit and a second image by the second image sensor unit; generating, by the processor, a first depth map based on the first image and the second image; subjecting, by the processor, one of the first image and the second image to edge-detection processing so as to obtain a number of edge pixels of said one of the first image and the second image which has undergone the edge-detection processing; determining, by the processor, whether the number of edge pixels is smaller than a first preset pixel number; controlling, by the processor, the light source to emit light when it is determined that the number of edge pixels is smaller than the first preset pixel number; controlling, by the processor, the second image sensor unit to detect light in the second range of wavelengths for generation of a third image by the second image sensor unit; generating, by the processor, a second depth map based on the third image; subjecting, by the processor, the first depth map and the second depth map to image fusion processing so as to obtain a fused depth map; and registering, by the processor, the fused depth map with one of the first image and the second image so as to generate three-dimensional point cloud data.