| 摘要 |
A method having the steps of accumulating charge in a photo sensor to arrive at a photo sensor voltage; incrementing a value in a counter; generating a reference voltage based on the value in the counter; determining whether the photo sensor voltage is greater than the reference voltage; and, if the photo sensor voltage is greater than the reference voltage, then loading a memory with the value in the counter. An apparatus having a photo sensor; a comparator coupled to the photo sensor; a switching element coupled to the photo sensor; an AND-gate coupled to the comparator; and, a memory coupled to the AND-gate. |
