LED strobe for hazard protection systems
A light-emitting diode (“LED”) based strobe may be used in automated system to provide a visual alert to occupants and/or building personnel if an emergency condition exists. A LED based strobe provides an even distribution of light having a sharp, bright pulse of light desired for emergency evacuation using lower power consumption.
1 . A visual alert device, comprising:
a) a solid state light source configured to radiate light in response to a control signal, the light radiating at intensity at least 15 candela; and
b) a controller configured to control the solid state light source to periodically operate in accordance with a signal for activating occupant lighting.
2 . The visual alert device of claim 1 where the solid state light source comprises at least one light emitting diode (LED).
3 . The visual alert device of claim 2 where the solid state light source comprises a plurality of LED's arranged about a circumference of a disc to radiate light to a substantially common area.
4 . The visual alert device of claim 3 comprising a plurality of discs each having a plurality of LED arranged about the circumference of the corresponding disc, each of the LED's configured to radiate light to a substantially common area.
5 . The visual alert device of claim 1 where the solid state light source comprises at least one organic light emitting diode (OLED).
6 . The visual alert device of claim 5 where the visual alert device comprises a building hardware device.
7 . The visual alert device of claim 1 where the controller comprises a programmable current source configured to control a constant current provided to the light source.
8 . The visual alert device of claim 1 where the controller comprises a programmable current source configured to control a constant current provided to the light source according to an environmental condition of the visual alert device.
9 . The visual alert device of claim 8 where the environmental condition comprises an ambient temperature proximate to the visual alert device.
10 . The visual alert device of claim 8 where the controller comprises a processor to control the programmable current source.
11 . The visual alert device of claim 1 where the light source is controlled to have a flash rate in the range of about 20 to about 120 flashes per minute.
12 . The visual alert device of claim 1 where the controller is configured to operate the light source in any of a plurality of modes.
13 . The visual alert device of claim 12 where the plurality of modes comprises a diagnostic mode.
14 . An automated building system, comprising:
a) a plurality of building automation devices;
b) a central controller configured to receive information from the plurality of automation devices, the information related to environmental conditions for a building; and
c) at least one solid state light strobe configured to radiate a visual alert signal in response to an alert signal received from the central controller, the solid state light strobe including at least one hi-flux semiconductor device that emits light to a portion of a structure in a periodic flashing pattern, having an intensity and dispersion pattern in accordance with a recognized safety standard.
15 . The building automation system of claim 14 where the plurality of building automation devices are configured to monitor fire hazards.
16 . The building automation system of claim 14 , where the solid state light strobe comprises a plurality of hi-flux light emitting diodes (LED's).
17 . The building automation system of claim 14 , where the solid state light strobe comprises a plurality of hi-flux organic light emitting diodes (OLED's).
18 . A method for providing a visual alert to occupants of a building, comprising:
monitoring a building environment for a hazard; and
providing a visual alert using a solid state visual alert device in response to detecting a hazard condition, the visual alert including light being radiated from a semiconductor device at with an intensity in accordance with a recognized safety standard associated with the detected hazard.
19 . The method of claim 18 further comprising:
monitoring the building environment for by-products of combustion; and
providing the visual alert using the solid state visual alert device in response to detecting a by-product of combustion.
20 . The method of claim 18 where the semiconductor device comprises a plurality of light emitting diodes.