| 摘要 |
Disclosed is a light bar such as for use is a warning or signal light. The light bar is comprised of a plurality of light heads (12), each light head (12) including a heat sink (20), a circuit board (22), a chip-on-board (COB) light-emitting diode (LED) (14), an optical concentrator, an optical collector (42), an optical collimator (44), an optical diffuser (54), a transparent housing and a microcontroller. The plurality of light heads (12) are housed within the transparent housing. The circuit board (22) is in heat transfer communication with the heat sink (20) and has an electrically conductive pathway. The COB LED (14) is mounted directly in contact with the circuit board (22) such that heat generated by the COB LED (14) when energised is transferred to the circuit board (22). The COB LED (14) has an LED chip (32) electrically connected to the electrically conductive pathway of the circuit board (22). The optical concentrator is a compound parabolic concentrator (CPC) and is mounted adjacent to the COB LED (14) to capture light emitted by the COB LED (14) when energised and to transmit the captured light. The optical collector (42) is adjacent the optical concentrator and is arranged to receive and transmit light from the optical concentrator. The optical collimator (44) is adjacent to, and spaced apart from, the optical collector (42) to receive and transmit light from the optical collector (42) such that light transmitted out of the optical collimator (44) is a spatially uniform beam. The optical diffuser (54) is adjacent to the optical collimator (44) and arranged to receive the spatially uniform beam of light transmitted out of the optical collimator (44) and produce an output light pattern. The output light pattern is substantially rectangular and horizontally diverging at an angle which is greater than a horizontal divergence angle of the spatially uniform beam. The microcontroller is electrically connected to each of the COB LEDs (14) to energise the LED chips (32) of the plurality of light heads (12) so that the combined output light patterns of transmitted light from the plurality of light heads (12) creates warning light signals. The warning light signals are substantially rectangular and horizontally diverging at an angle which is greater than a horizontal divergence angle of the spatially uniform beam when viewed by an observer remote from the light bar.
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