Illumination system of vein imaging instrument

The illumination system comprises a camera, a semitransparent mirror, an infrared light source and a shell, a cavity is formed in the shell, an opening is formed in one side of the shell and communicated with the cavity, the camera and the semitransparent mirror are both arranged in the cavity, the camera is right opposite to the opening, and the infrared light source is arranged in the cavity. The semitransparent mirror is arranged between the camera and the opening, and the infrared light source is installed on the shell. According to the utility model, the camera is arranged in the cavity, so that the camera is basically located in a closed environment and only receives light entering from the opening as far as possible, and the semitransparent mirror is also arranged and can effectively filter the light before entering the camera, so that other interference light received by the camera except infrared light is effectively reduced, and the safety of the camera is improved. Therefore, the accuracy of the ve