| 摘要 |
PURPOSE: To effectively remove heat of a light source. CONSTITUTION: A light source block 32 has a space 8 into which a light source lamp 4 is inserted, and a light passing hole 14 leading to is space 8 is opened. The light passing hole 14 is communicated with a measuring optical system 12 by a cylindrical inside spacer 16. In order to pass a cooling air separately from the light passing hole 14, plural ventilation holes 32 penetrating in one direction are arranged in the light source block 30, and the ventilation holes 32 are joined to a fan 46 through a ventilation pipe 42. When a lamp 4 is lighted, the fan 46 is actuated, and the air from the fan 46 flows to the ventilation holes 32 through the ventilation pipe 42, and the light source block 30 is cooled. |
