| 摘要 |
PURPOSE:To improve remote control performance by turning on plural projecting means instantaneously and sequentially with time difference, not simultaneously. CONSTITUTION:Three projecting elements IR1-IR3 are turned on in a short cycle, that is, instantaneous times t1-t3, sequentially with time difference not so as to be turned on simultaneously. The sequential turning-on is repeated several times. Namely, from the time t1 to the time t2, the projecting element IR1 emits light, an arithmetic processing circuit 8 calculates a distance up to an object at that time. From the time t2 to the time t3, the projecting element IR2 emits light to find a range. Therefore, each projecting means can take a longer dormant time, which is advantageous to the heating of the projecting means to increase a peak current. Thus, light emitting power increases, the remote control performance is improved, and the entire range finding time is shortened. |
