| 摘要 |
<p>PURPOSE: To specify a fault light emitting element or light receiving element by emitting light through a process of selecting one light emitting element, and by receiving reflected light from a cover by two or more light receiving elements. CONSTITUTION: Light, emitted from a light emitting element 8, passes through a semi-translucent cover 28 whose most part is positioned in the front part, but the light is received in part by a light receiving element 17 of an adjacent holder 25. When fault element is specified to be changed, when light emitting elements 8,..., 15 are lighted sequentially, the light emitted from the light emitting element 8 is received by the light receiving elements 16, 17, and then the light emitted from the light emitting element 9 is received by the light receiving elements 17, 18. The result is written in the memory of a controller 29 and calculated to decide a specified fault light receiving element. When the fault element is specified, the fault element is displayed on a display part on the basis of at signal from the controller 29.</p> |
