Toxic and harmful gas monitoring device with light focusing function

The utility model provides a toxic and harmful gas monitoring device with a light focusing function. The toxic and harmful gas monitoring device comprises a fixing device, a concave reflecting mirror,a plane reflecting mirror, a xenon lamp and a corner mirror, wherein the fixing device, the concave reflector, the plane reflector and the xenon lamp are respectively arranged on the bottom plate, and the bottom plate can vertically and horizontally move; the concave reflecting mirror, the plane reflecting mirror, the xenon lamp and the corner mirror are arranged in sequence; the fixing device isconnected with the optical fiber, one end of the optical fiber forms an incident end face on the fixing device, and the other end is connected with the spectrometer; a small hole is formed in the center of the concave reflecting mirror, a semi-transparent and semi-reflecting mirror is arranged between the fixing device and the concave reflecting mirror, and a CCD imaging device is arranged abovethe semi-transparent and se