| 摘要 |
PURPOSE:To scan a plane in an equal speed with a simple constitution, by driving a galvanomirror with a signal which has the waveform changed nonlinearly for time. CONSTITUTION:A galvanomirror 6 is driven by a signal (i), which has the waveform changed nonlinearly for time, obtained by synthesizing a saw-tooth wave S1 and a signal S2, which becomes a cosine wave in a section nT<t<(n+1)T [(n) is an integer and T is the period], in a required proportion by addition, and the irradiation luminous flux due to a light source 1 and a lens 2 is reflected by the mirror 6 to scan a photosensitive paper 7 or the like optically, and thus, the speed of movement of a light spot due to the scanning light on the projection face of the photosensitive paper 7 becomes constant. Consequently, the plane is scanned in an equal speed in a simple constitution where optical systems such as an ftheta lens are unnecessary. Otherwise, galvanomirror driving signal information which is stored in an ROM or the like and has the waveform changed nonlinearly is read out to drive the galvanomirror. |
