Fully sealed streamline（top） lid has been designed with aerodynamic principle, which decreases the flow resistance. This design can make the clean laminar flow through the operating area directly and ensure the flow circulation to make the operating room sterilized and purified. Multiple-facet with more than 1000 facets, designed by CAD/CAM technique, reflects the light from different angle, which creates excellent shadowless effect and focusing depth. The color temperature and color-rendering index is close to average daylight, the surgeon can see the real color of the tissue and organ during operation. Endothermal material, accordant with German Standard (SCHOTT/KG3) and Japanese standard (HOYA/HA-30), increases the light efficiency greatly and decreases the energy of the operating area