| 摘要 |
PURPOSE:To prevent a stain dewing and generation of heat lens effect of a optical part with dust, etc. CONSTITUTION:A manifold 103 is arranged at a clean air introducing part 100 of a mirror unit 12A, the clean air is once supplied to the manifold 103 through a regulator 45A and a connector 102, passed through the manifold 103 and the clean air is made to a uniform flow, jetted from an air blowing opening 106, blown in parallel to the surface of a mirror 11 and reaches a duct 122 of a clean air discharging part 120. Then, it is sucked by a fan 204 and discharged. And a sub-blowing opening 104 is arranged at the clean air introducing part 100, the clean air introduced through a connector 101 is allowed to flow from this sub-blowing opening 104 into a space 107 inside the mirror part 110 and made so as to cover over the circumference. |
