| 摘要 |
PURPOSE:To extract only collimated light by closing an opening part for projecting collimated luminous flux with cover glass and holding a semiconductor laser and a collimation optical system in the closed space by a holding member in specific position relation. CONSTITUTION:An outer package member 30 is in a box shape and has the opening part 30A, which is closed with the cover glass 40 to hold the inside of the outer package member 30 airtight. The semiconductor laser 1 and collimation optical system 2 are held by the holding member 50 and fixed at specific positions in the internal space of the outer package member 30. Light which is radiated by the semiconductor laser 1 and made incident on a micro-Fresnel lens is collimated. Then the size of the opening part 30A is so determined that only the light which is collimated by the collimation optical member 2 as to the light emitted by the semiconductor laser 1 is projected from the outer package member 30. Thus, only the collimated luminous flux of the luminous flux from the semiconductor laser can be extracted as effective luminous flux. |
