| 摘要 |
PURPOSE:To manufacture various laser printers which differ in printing speed and resolution with excellent productivity by forming reflecting surfaces at specific positions within constant angles on the centers of rotation of respective polygon mirrors. CONSTITUTION:When the maximum number of reflecting surfaces 28 which is set for a polygon mirror 29 is (n) and the number of reflecting surfaces 28 of the polygon mirror 29 which is a measure of the maximum number (n) is (m), the (m) reflecting surfaces 28 which are formed in an angle thetaa on the center of rotation of each polygon mirror 29 are formed at intervals of an angle omegathetaa so that n=m(x+1)=3600 deg./2thetaa and 360 deg.=m(2thetaa(x+1)) hold. Therefore, neither the specular surface machining of unnecessary reflecting surfaces 28 nor the specular surface machining of a specific outer peripheral surface of a base material which is formed in a polygonal disk shape previously is required when the polygon mirror 29 is manufactured. Consequently, polygon mirrors 29 which differ in the number of reflecting surfaces 28 can easily formed without changing the settings of a matching device nor replacing the jig. |
