| 摘要 |
PURPOSE:To utilize the peripheral wall of an opening part as a heat discharging part so that heat generated from a light emitting source can be efficiently discharged even if respective optical system members are made of glass by covering respective optical system members with a cover having a heat discharging function and opened so as to expose a prescribed area of an objective lens. CONSTITUTION:The periphery of the optical system members such as the objective lens 2, triangular prisms 1, 3 and a concave lens 4 built in a device body is protected by a cover 10. The opening part 11 is formed on the upper wall of the cover 10 so as to expose the prescribed area of the objective lens 2 and the peripheral wall part around the opening part 11 has a diaphragm structure for shielding excess light out of the light irradiated from the light emitting source 5. A part of said cover 10 is directly contacted with the light emitting source 5 and heat generated from the light emitting source 5 is thermally transmitted through the cover 10 and discharged from the peripheral wall part or the like around the opening part 11 to the outside. |
