| 摘要 |
PURPOSE:To perform distance measurement in a wide luminance range by providing a light receiving means for monitoring, comparing the integrated value of stored charges in the light receiving means with two, large and small, reference levels, first comparing it with the large level, comparing it with the small level by stopping the storage of charge when it is not detected and amplifying an image signal from a line sensor with a small amplification factor at the time of the large level and with a large amplification factor at the time of the small level in a distance measuring instrument using a charge storing type line sensor. CONSTITUTION:In a driving control circuit 11a, a sensor driving signal is inputted to a line sensor 8, a signal for selecting one of two reference levels S1, S2 (S1>S2) to a reference level generating circuit 11d, a signal for selecting one of two amplification factors G1, G2 (G1<G2) to an amplifier circuit 11c, either of S1, S2 is sent from the generating circuit 11d to a level detecting circuit 11e as a detected level, is compared with the integrated value of the output of a light receiving means 7 for monitoring and the detected signal LV is inputted to the driving control circuit 11a. S1 and G3, S7 and G3 are combined with, first comparison with S1 is performed and comparison with S2 is performed when it is not detected. |
