| 摘要 |
PURPOSE:To simplify a circuit structure and facilitate an offset process in charge storing units by constituting a photoelectric detector such that electric charge transfer paths are inverted between the period when light emitting means are emitting light and the time when the means do not emit light. CONSTITUTION:Two pairs of charge storing units a; c and b; d correspond to other two pairs of photoelectric transducer units A; C and B; D, respectively, among a plurality of the photoelectric transducer units A, B, C and D. Electric charge transfer paths are inverted by switching means 10 between the time when light emitting means are emitting light and the time when the light emitting means do not emit light. A signal component to be detected and corresponding to the quantity of the light emitted from the light emitting means, that is, an output corresponding to the difference between the charge stored in the two charge storing units is detected by differential signal detector means 117 and 118, from said difference the charge corresponding to a background light component being removed. Thus, a circuit structure is simplified in compliance with a decrease in the number of the charge storing units and an offset process in the respective charge storing units is facilitated. |
