| 摘要 |
<p>PROBLEM TO BE SOLVED: To efficiently light a rectangular area by causing the maximum of converging angles made by light flux converged by a converging means with an optical axis to differ between two directions to cross at right angle with each other. SOLUTION: A converging means 2 has a rectangular opening. This causes angle distribution of light flux incoming into an optical integrator 4 to differ between the length and width directions of cross-sections of respective element lenses, and the maximum converging angle made by the light flux with an optical axis is decreased in the width direction of the rectangular cross-sections of the respective element lenses and increased in the length direction thereof. This enables a group of convergence points to be efficiently formed near outgoing surfaces of the respective element lenses. The light flux from the convergence points group thus formed has outgoing angle distribution different between the two normal-crossing directions, the length and width directions, of the rectangular cross-sections of the respective element lenses, and an angle made by distributed outgoing light flux with the optical axis is larger in the length direction than in the width direction. This causes a rectangular lighted area to be efficiently formed.</p> |
