| 摘要 |
An integrator type illumination optical system has a first lens array and a second lens array. The first lens array includes left, center, and right column groups. The thickness of the lens cells of the center column group is thinner than that of the lens cells in other column groups, and the thickness of the lens cells in the left and right column groups increases from the inner column outward gradually. The lens cells in the left and right column groups are shaped to converge incident light away from the optical axis of the integrator type illumination optical system, and the lens cells in the center column group are shaped to converge incident light toward the optical axis of the integrator type illumination optical system. |
