| 摘要 |
PURPOSE:To prevent or reduce measurement error caused by chipping, to improve the output S/N of a light receiving element and to measure long distance by permitting the light receiving equipment of a range finding device which has the light receiving equipment on both sides of a light emitting element to be two-piece photodiodes. CONSTITUTION:The two-piece photodiodes are used for the light receiving equipment 5A and 5B, and when a object 10 is at the specified position between a focus exceeding distance and the shortest photographing distance of a camera, the dividing line of the photodiodes is image by light receiving lenses 6A and 6B. The image is adjusted to be at the center of a light spot image. When the output of the elements inside the light receiving equipment 5A and 5B are represented as I11 and I21 respectively, and the output of the elements outside as I12 and I22, I11+I21 or I12+I22 is input to a calculating amplifying equipment 8A or 8B. Therefore, the output of the calculating amplifying equipment 8A or 8B is defined by the expression I. This output is input to a calculating equipment 9 and IA/IB or (IA-IB)/(IA+IB) is calculated. Thus, a distance signal independent of the illuminance of the light spot image is obtained. |
