| 摘要 |
A lighting device is constructed with LED light sources and a power control to project light along a selected direction throughout an angular range of tilt of the lighting device about a vertical. The power control includes a tilt switch or tilt sensor which is responsive to the angular displacement of the lighting device about a vertical plane. A plurality of beams are arranged to project a plurality of oblique light beams. If during its deployment the lighting device is angularly displaced about the vertical, the power control selectively energizes the beam which projects a light beam including the selected direction when the lighting device is angularly displaced. The divergence of the selected light beam from the selected direction when the light is vertical counterbalances the effect resulting from the angular displacement of the lighting device about the vertical permitting the light beam emerging from the lighting device to emerge directed along the selected direction throughout a range of angular tilt of the lighting device.
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