| 摘要 |
Traffic signal head 1 comprises an array of contiguous LED 2 forming a visual indicator which is of a particular colour (e.g. red) when on. The array incorporates at least three LED groups 3-5 with illumination control means (e.g. pulse width modulated) connected to each. The LED groups are asynchronously activated in order to illuminate at least 60% of the visual indicator whenever it is on. The LED groups may form clusters; concentric LED rings [11-13, Fig.2]; or circular sections [23-25, Fig.3]. A traffic feedback system may comprise the signal head and a trigger device which activates a camera to capture an image incorporating at least one activated LED group. This avoids the problem of traffic light violation images taken during the space period of a red light falsely exonerating a driver. |
