摘要 |
A method of controlling an output of a photosensor which comprises a light emitting element and a light receiving element. The quantity of light emanating from the light emitting element is varied from a predetermined value. A quantity of light output from the light emitting element when the output level of the light receiving element has reached a predetermined value is detected. This specific light quantity is multiplied by a predetermined value larger than or smaller than 1 (one), thereby preparing a reference light quantity for the light receiving element.
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