1. Optical system is five gears ,zoom ,and focus, Strong three-dimensional sense, Distinct gradations, Wide view. 2.The double optical path cold light source of the integration design and the fiber conduction system. The brightness can be adjusted 3.The unique light splitting grating design and the sole CCD imaging vernier device ,making the screen form the three-dimensional imaging, and all the different levels diseased region tissue can gain the best observation effect.