| 摘要 |
PURPOSE:To focus a photographing lens to the midpoint of an image plane constantly and correctly and to prevent the occurrence of defocus due to parallax by irradiating infrared rays for range finding toward the midpoint of an image plane to be photographed. CONSTITUTION:A deflecting member 1 deflecting an infrared ray emitted from a light emitting element 8 between a projecting lens 9 and the element 8 is arranged freely tiltably, and makes the ray incident in a position deviating from the center of the projecting lens 9. A deflecting member tilting means is provided to tilt the deflecting member 1 in interlocking with the move of a focus lens. The infrared ray 4 emitted from the light emitting element 8 is deflected according to the inclination of the deflecting member 1, whereby the ray is cast toward an object on the optical axis X-X of the focus lens. Consequently, the infrared rays for range finding always irradiates the midpoint of the image plane to be photographed. Thus, the photographing lens can be focused on the midpoint of the plane constantly and correctly. |
