| 摘要 |
PURPOSE: To inexpensively make distance measurement of high accuracy possible by setting distance measuring information to a long distance when a light receiving signal is equal to a specified level or more and obtained distance measuring information outputs information beyond the predetermined distance measuring interconnection range. CONSTITUTION: An infrared emission diode IRED4 which is a casting element for distance measurement is driven and casting is started. Next, an output discrimination means 7 judges whether a signal of a semiconductor position detector PSD5 is small or large. If the output signal is small, an object to be distance-measured is distant, and as reflection light is not returned, the distance is set at a long distance by a distance determination means 9. If the output signal is large, distance measuring output is obtained by a distance operation means 8. The output of the operation means 8 judges whether it is beyond the distance measuring interconnection range, and if it is over thereof, the distance is set at a long distance as abnormal. In addition, if it is within the range, the distance is set by the distance determination means 9 as reflection light from the object to be distance-measured on the basis of the output from the operation means 8, and distance measuring operation is completed. |
