Patent ID: 6396633
Filing Date: 2002-05-28
Classification: G02B

Abstract:
An optical reflector having a glass substrate, upon at least one of main surfaces thereof are formed, sequentially, a film having a refractive index n1 at a wavelength of 550 nm; a film having a refractive index n2 at said wavelength; a film having a refractive index n3 at said wavelength; and a film having a refractive index n4 at said wavelength, wherein:there is established a relationship as indicated below between refractive indices n1, n2, n3 and n4; n1&gE;n4>n3>n2film thickness of said film of the refractive index n2 is equal to or greater than 30 nm and is equal to or less than 60 nm; a reflectivity to visible light is equal to or greater than 75% upon said film of the refractive index n4; and a value of {(a*)2+(b*)2}Â½ is equal to or greater than 0 and is equal or less than 10, when representing a color tone of reflected light upon a surface of said film of refractive indices n4 by a* and b* (psychometric chroma coordinates).