Patent ID: 6760138
Filing Date: 2004-07-06
Classification: G02B

Abstract:
An optical scanning apparatus in which a light beam from a light source is deflected and forms an imaging spot on a surface to be scanned, said apparatus comprising:said light source having a wavelength of 500 nm or less; and a reflecting mirror which reflects the light beam from said light source, wherein if a complex refractive index N of a metallic film contributing to a reflection characteristic of said reflecting mirror is defined as N(&lgr;)=n(&lgr;)âˆ’ik(&lgr;) where n, k>0; n(&lgr;) is the real part of the complex refractive index; i={square root over (âˆ’1)}; k(&lgr;) is the imaginary part of the complex refractive index (exhaustion factor); and &lgr; is the wavelength, then the reflecting mirror satisfies a condition: k(&lgr;)>{square root over ((âˆ’n(&lgr;)2+18n(&lgr;)âˆ’1))}.