| 摘要 |
PURPOSE:To quicken the lens removal by forming the structure of inserting the holder fitted to a condensing lens from the opening part formed on a housing and fixing it to the housing with holding the airtight state with a seal member. CONSTITUTION:A condensing lens 4 is fitted to the holder 3 having the plane part 3a formed by notching at the position where both sides are opposed the annular one part of an annular outer periphery. The opening part 11 having the width made coincident with the gap of the plane part 3a and annular groove 10 are formed on a housing 2. The plane part 3a of the holder 3 fitted with the condensing lens 4 is inserted to the opening part 11 of the housing 2, the holder 3 is rotated by the lever 12 provided on the holder 3 and fixed to the housing 2 with holding the high airtight state with a seal member. Consequently the workability can be improved because the removal of the condensing lens is easily performed. |
