Patent ID: 6369929
Filing Date: 2002-04-09
Classification: G02B,H04N,Y10S

Abstract:
A method for scanning an inner face of a cylindrical drum with two light beams, comprising the steps of:introducing said two light beams into the drum; deflecting said two light beams introduced into the drum by a spinner rotating within said drum, toward the inner face of the drum to scan the inner face with the two deflected light beams; wherein said two light beams are one-dimensionally deflected in mutually orthogonal directions with each other, respectively, in synchronism with a rotation of said spinner, an interval between said two light beams, being kept constant, prior to said two light beams being introduced to the spinner; wherein in an X-Y rectangular coordinate system on an image focusing plane of the light beams, an X axis being defined as a direction in which a first light beam of said two light beams reciprocates while being one-dimensionally deflected, a Y axis being defined as a direction in which a second light beam of said two light beams reciprocates while being one-dimensionally deflected, the light beams are one-dimensionally deflected so that said first light beam satisfies x=râ€¢cos(&ohgr;t+&psgr;), y=0 and said second light beam satisfies x=0, y=râ€¢sin(&ohgr;t+&psgr;) where r is an interval between both light beams &ohgr; is a rotation angular velocity of the spinner, t is a time and &psgr; is an offset angle in a maximum deflecting direction of the spinner.