| 摘要 |
PURPOSE:To easily uniform illuminance distribution on an exposure surface even when one lens array is used, by providing a dimming plate which has a perforation pattern making the quantity of transmitted light less at a position corresponding to an overlap part than that at other parts. CONSTITUTION:So that the quantity of transmitted light is made less at respective overlap parts A of a lens array than at other parts B, a dimming plate 3 having slanting slits 2 in a special shape wherein the parts A and B differ in slit width is arranged between the lens array and an exposure surface. In this case, crosspieces 4 of the slanting slits 2 are provided succeeding in common between the parts A and B, and the width of the crosspieces 4 vary gradually at boundaries between the parts A and B, achieving the best dimming. |
