| 摘要 |
A reflex speaker which provides an acoustic signal generator for acoustic alarm signals is captured in a housing through which the acoustic signals project via ports at the exit end of the housing. The housing defines a compartment at the exit end with an opening which is covered so that the acoustic signals project out of the exit end around the compartment. The cover may be a transparent cover which provides a lens through which optical signals generated by optics in the compartment provided by either LEDs to provide an optical warning signal, or a video camera, such as a CCD, which responds to visual signals as from hazards at the rear of the vehicle. |
