| 摘要 |
PURPOSE:To provide a satisfactory field of view while simplifying driver's operation of a wiper device by controlling automatically the operational condition of the wiper according to rain amount. CONSTITUTION:A rain drop detector 14 is provided within the extent of wiper movement on a front window glass 11 of an automobile, and constituted of a light source 12 consisting of an emitting element 16 such as light emitting diode and a light receiving element 18 for receiving light sent from said light source and reflected inside the glass 11. The emitting element 16 and light receiving element 18 are respectively provided with transparent materials having the same refractive index as the glass 11 to improve efficiency of radiation or incidence. When rain drops are attacked to the detectors 14, an amount of light received by the element 18 is varied to thereby control the operational speed of the wiper. |
