Light source with gradually changing intensity

Details Light source with gradually changing intensity Light source with gradually changing intensity

G - Physics

04

C

315/73

G04C 19/02 (2006.01) H05B 37/02 (2006.01)

Patent

CA 1314069

ABSTRACT A device and method of awaking a sleeper includes an alarm clock coupled to a control circuit for controlling the power provided to a lamp. After the alarm clock wake-up signal is provided, the light intensity emitted by the lamp slowly, smoothly and gradually increases. The time interval over which the light intensity increases is selectable by the user but will usually be in the range of thirty minutes to an hour. The circuit for increasing the light intensity is designed to ensure that the intensity increase is smooth, especially at the beginning of the wake-up cycle. A photo resistor adjacent an LED is part of a parallel resistive network which lowers the firing angle of a triac to increase the intensity of the light. The LED is biased in the on state to minimize transients as the current through the LED varies. The use of a parallel resistive network causes the firing angle to change more slowly when the light is very dim then when the light intensity is bright because the human eye is more sensitive to light intensity variations when the background light level is low than when it is high.

606263

Affiliated with

Also associated with

Rating

Light source with gradually changing intensity does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Light source with gradually changing intensity, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Light source with gradually changing intensity will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFCA-PAI-O-1252082