Adopting the ring fiber lens; Adopting the halogen cold light source (15V, 150W); Adjustable brightness and a green filter; Advanced image processing technology, can achieve the functions of marking, calculation of areas, zooming images; With the editing functions of access images, freezing, collection, delete images, etc; Images can be collected continuously, and display a number of images on the same screen and convenient to contrast, full-screen display; The reports can be printed into multiple formats.