| 摘要 |
The present invention is directed to lighting apparatus and methods for controlling lighting apparatus using ambient light levels. A controller within a lighting apparatus is used to activate and deactivate one or more light radiating devices within a duty cycle. In a first stage, the controller uses a light detection apparatus to sample the ambient light level at a plurality of sampling times during which the light radiating devices are deactivated. The light level when the light radiating devices are deactivated is an indication of the ambient light levels within the surrounding area of the lighting apparatus. The sampling times occur in different duty cycles within a survey time period. The controller determines an average for the light levels sampled over the survey time period, thus generating an averaged ambient light level over the survey time period. In a second stage, the controller adjusts an intensity of the light radiating devices based at least partially upon the averaged ambient light level. The controller may generate a target light level using the averaged ambient light level over the survey time period and a desired light level and, over an adjustment time period, incrementally adjust the intensity of the light radiating devices towards the target light level. |
