Patent ID: 6147806
Filing Date: 2000-11-14
Classification: G02B

Abstract:
A light separation apparatus using a flat plate formed of a material comprising:a wide band anti-reflection coating film for allowing an incident light beam generated by a light source to penetrate into the material at a first angle without reflection;a first dichroic mirror allowing only a light beam with a first wavelength to penetrate outside the material at said first angle and reflecting light beams with other wavelengths at a second angle, from the light beam penetrated through said wide band anti-reflection coating film;a wide band high-reflection coating film reflecting at the second angle the light beam reflected by the first dichroic mirror;a second dichroic mirror allowing only a light beam with a second wavelength to penetrate at the first angle so that it is parallel to the light beam with the first wavelength penetrated by the first dichroic mirror, and reflecting the light beam with a third wavelength at the second angle, from the light beam reflected from the wide band high-reflection coating film;the wide band high-reflection coating film reflecting at the second angle the light beam with the third wavelength reflected by the second dichroic mirror;an anti-reflection coating film allowing the light beam with the third wavelength to penetrate outside the material at the first angle without reflection so that it is parallel to the light beam with the second wavelength penetrated through the second dichroic mirror; andwherein the light beam penetrated through the wide band anti-reflection coating film and the light beam reflected by the first dichroic mirror, the second dichroic mirror, and the wide band high-reflection coating film pass through the material.