| 摘要 |
System and method are provided for controlling emergency lighting where emergency lights turn on when main source of power goes out for controlling emergency lighting to conserve energy utilized by the emergency light, while maintaining good visibility of the emergency lighting. Solid state lighting, such as LED, is used within an emergency light to add light in blue wavelength region matching the light output to the most sensitive of wavelength response of the human eve to increase color perception and allows faster response time. Electrical current to the device and light output are reduced while LED light tends to increase its blue wavelength component as it is dimmed thus increasing effective light output. After a predetermined time, the light is purposefully dimmed to conserve energy and to allow the eye to slowly and safely adjust to the new lighting conditions. By reducing electrical current, energy storage batteries may be smaller than for similar unit that maintains constant light output.
|
