| 摘要 |
PURPOSE:To provide a distance measuring device for an autofocusing apparatus which can surely focus even when there exist a plurality of subjects, measure a distance to the subject accurately and rapidly and surely obtain distance measurement data even when a mounting error occurs at a light-receiving sensor. CONSTITUTION:An adjustment means is provided so that a subject is caught by three pairs of light-receiving sensors constituted by line sensors 10b, 20b and 30b, a zero-cross point for a secondary difference of its luminance distribution is calculated and detected, a coincidence point of three zero-cross behaviors concerning an output signal of these three pairs of light-receiving sensors is detected by making one of these three pairs of light-receiving sensors as a reference and appropriately displacing the other two to measure a distance to the subject by a displacement amount of the zero-cross behaviors of two light-receiving sensors at coincidence, and that distance measurement data can be obtained by arbitrary two pairs of light-receiving sensors including a reference sensor when one pair of the three pairs of light-receiving sensors are made as a reference sensor. |
