| 摘要 |
PURPOSE:To prevent uneven printing by moving two light intercepting plates each fixed with two cylinders, respectively, always in the same direction, one later than the other by predetermined time duration, to open and close the upper part of the opening of the shutter, and controlling the shutter opening time to render the final time length of the exposure of a work to a luminous exposure flux constant. CONSTITUTION:The upper part of each of light intercepting plates 36, 37 is fixed with screws to one end of each of piston rods 34, 35 fitted into each of cylinders 21, 22, respectively, and each of the plates 36, 37 are arranged in parallel to the opening part 20 of the shutter. The plate 36 covering the part 20 is moved in the direction of the side 20b to fully open it, and passes the luminous flux through it to print the work. The other plate 37 staying on the side 20a is moved with an arithmetic unit to cover the part 20, and next, the plate 36 is moved on the right side, then the plate 37 is moved on the right side to return them to the initial state, thus opening and closing the opening part 20. Since the shutter is opened and closed in the same direction and the exposure time length is kept constantly, uneven printing can be prevented. |
