Light receiving device and distance measuring device

Abstract

A light receiving device of the present disclosure includes: a pixel array unit having a plurality of pixelstoeach including a light receiving unittothat generates a signal according to reception of photons; a first switch unit thattorecharges the light receiving unitto; and a recharge control unitthat controls the first switch unittoaccording to output of the light receiving unitto, and the recharge control unitis shared among the plurality of pixelsto. By this sharing of the recharge control unit, since the circuit area of the circuit unitper pixel can be reduced, the aperture ratio can be increased while miniaturizing the pixel. Preferably, the recharge control unitincludes a four-input OR circuitand a recharge signal generation circuit. The OR circuitobtains the OR of the logic signals retrieved from each cathode electrode of the SPAD sensorstosupplied through the comparatorsto. The OR output of the OR circuitis supplied to the recharge signal generation circuit. The recharge signal generation circuitgenerates the recharge signal RCHG by delaying the OR output of the OR circuitby a predetermined delay time, and supplies the recharge signal RCHG to the first switch unitsto. As a result, the recharge control unitperforms the recharge control in response to the OR signal of the logic signal whose logic is inverted at the time when photons are incident on one or more of the SPAD sensorsto. Furthermore, a distance measuring device of the present disclosure includes: a light source that irradiates an object to be measured with light; and a light receiving device that receives light reflected by the object to be measured, and the light receiving device includes the light receiving device having the above configuration.