| 摘要 |
PURPOSE:To display an image on a rectangular picture plane by changing expanding magnification in the X and Y axis directions and changing the changing magnifications of X and Y axes in accordance with the expanding magnification. CONSTITUTION:A photographing optical part 9 consists of projection lenses 15, 16, the projection lens 15 expands both the X and Y axes uniformly by n times and the projection lens 16 is a semicircular type lens expanding the X axis by (m) times and the Y axis by unmagnification, so that an image obtained through the two projection lenses 15, 16 can be expanded by (m).(n) times in the X axis and (n) times in the Y axis. Speed control circuits 22X, 22Y control the X axis moving speed and Y axis moving speed of an optical axis of a laser beam in accordance with speed command values outputted from circuits 21X, 21Y. The outputs of the circuits 22X, 22Y are inputted to a mirror driving system 31. Magnification correcting circuits 25, 26 formed for the X axis side correct magnification so that the ratio of the X axis to the Y axis is m times on the basis of the expanding magnification of a projection optical part 9 and only the X axis is set up to 1/m (magnification of Y axis projection optical part/magnification of X axis projection optical part) by correcting units 25, 26 on the basis of a speed command and a position command. |
