摘要 |
An optical lighting control, such as that used to control street lamps, delays the response of the lamps to changes of illumination while the lamps are on at night but avoids the delay in response to daylight. Thus, headlamps, flashlights, and lightning flashes of brief duration do not cause the control to turn off the street lamps. However, the street lights turn off without this delay in response to daylight.
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