| 摘要 |
PURPOSE:To eliminate the need to adjust the parallelism between beams with simple structure by forming a total reflecting layer on one surface and a reflection preventing layer on the other surface of a transparent substrate having parallel surfaces, further a reflecting layer on the same material with the substrate at some part on the reflection preventing layer. CONSTITUTION:The optical path of incident laser light 11 is split by the surface of the reflecting layer 7 which is made of the same material with the transparent substrate 5 or has nearly the same refractive index to obtain the 1st reflected light 11 and transmitted light 12. The transmitted light 12 when entering the reflecting layer 7, reflection preventing layer 6, and transparent substrate 5 is refracted according to Snell's law to travel straight, and then reflected by the boundary surface between the transparent substrate 5 and total reflecting layer 8. The refracted light when passing through the boundary surface between the transparent substrate 5 and reflection preventing layer 6 and the reflection preventing layer 6 itself is refracted according to their refractive indexes to obtain the 2nd reflected light 13. The refraction of this 2nd reflected light 13 is canceled in its optical path to obtain a beam parallel to the 1st reflected light 11. Thus, the simple structure eliminates the need to adjust the parallelism between beams. |
