Method and apparatus for a variable intensity pulsed L.E.D. light

• US 7,186,000 B2
• Filed: 09/20/2004
• Issued: 03/06/2007
• Est. Priority Date: 03/19/1998
• Status: Expired due to Fees

• Current Assignee: Lemaire Illumination Technologies LLC
• Original Assignee: Charles A. Lemaire
• Inventors: Lebens, Gary A., Bourn, Charles T., Lemaire, Charles A.
• Primary Examiner(s): NEGRON, ISMAEL
• Assistant Examiner(s): NEGRON, ISMAEL
• Application Number:
  US10/945,801
• Publication Number:
  US 20050040773A1
• Time in Patent Office: 897 Days
• Field of Search: 362/184, 362/183, 362/159, 362/249, 362/285, 362/208, 362/188, 362/800, 315/307, 315/291
• US Class Current: 362/184
• CPC Class Codes: F21L 4/027 the light sources being a LED
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H04B 10/502 LED transmitters
• CPC Class Codes: H04B 10/564 Power control
• CPC Class Codes: H04N 23/74 by influencing the scene brightness using illuminating means
• CPC Class Codes: H05B 45/12 using optical feedback
• CPC Class Codes: H05B 45/20 Controlling the colour of the light
• CPC Class Codes: H05B 45/22 using optical feedback
• CPC Class Codes: H05B 45/32 Pulse-control circuits
• CPC Class Codes: H05B 45/395 Linear regulators
• CPC Class Codes: H05B 45/50 responsive to malfunctions or undesirable behaviour of LEDs; responsive to LED life; Protective circuits
• CPC Class Codes: Y02B 20/30 Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]
• CPC Class Codes: Y10S 362/80 Light emitting diode
• CPC Class Codes: Y10S 362/802 Position or condition responsive switch

Abstract

Improved method and apparatus for hand-held portable LED illumination. The illumination source includes a plurality of LEDs, and an electrical circuit that selectively applies power from the DC voltage source to the LED units, wherein the illumination source is suitable for handheld portable operation. In some embodiments, the electrical circuit further includes a control circuit for changing a proportion of light output having the first characteristic color spectrum output to that having the second characteristic color spectrum output, and that drives the LEDs with electrical pulses at a frequency high enough that light produced has an appearance to a human user of being continuous rather than pulsed. Still another aspect provides an illumination source including a housing including one or more LEDs; and a control circuit that selectively applies power from a source of electric power to the LEDs, thus controlling a light output color spectrum of the LEDs.

Claims

1. A method of providing changeable illumination of such compact size and low weight as to be suitable for single-handed portable operation by a user, comprising:

providing one or more LEDs in a housing, the LEDs having a first characteristic color spectrum output and one or more LEDs having a second characteristic color spectrum output, wherein the first characteristic color spectrum output is different from the second characteristic color spectrum output;

selectively applying pulsed power from a DC-battery-powered voltage source to the LEDs, wherein the pulses are of high-enough frequency such that the human eye does not perceive the pulses;

projecting light to illuminate an object separate from the housing; and

changing a pulse characteristic of the pulsed power in order to change a proportion of light output having the first characteristic color spectrum output to that having the second characteristic color spectrum output.

2. The method of claim 1, wherein the changing of the pulse characteristic increases light output level of the LEDs having a first characteristic color spectrum output by increasing a pulse width.

3. The method of claim 1, wherein the changing of the pulse characteristic increases light output level of the LEDs having a first characteristic color spectrum output by increasing a pulse energy.

4. The method of claim 1, wherein the changing of the pulse characteristic increases light output level of the LEDs having a first characteristic color spectrum output by increasing a pulse frequency.

5. The method of claim 1, wherein the changing of the pulse characteristic maintains an average predetermined light output level of the LED units by sensing a battery voltage and adjusting a pulse width to the LED units based on the measured voltage to maintain an average light output at a predetermined level.

6. The method of claim 1, further comprising:

providing one or more LEDs having a third characteristic color spectrum output, wherein the third characteristic color spectrum output is blue LED output, the second characteristic color spectrum output is green LED output, and the first characteristic color spectrum output is red LED output.

7. The method of claim 6, further comprising:

using one pair of buttons for blue LED output, a second pair of buttons for green LED output, and a third pair of buttons for red LED output.

8. The method of claim 6, further comprising:

using one pair of buttons to control the X-coordinate and another pair of buttons to control the Y-coordinate of chromaticity.

9. The method of claim 6, further comprising:

using information from a first user input device to control blue LED output, a second user input device to control green LED output, and a third user input device to control red LED output.

10. The method of claim 6, further comprising:

using information from a first user input device to control the X-coordinate of chromaticity and a second user input device to control the Y-coordinate of chromaticity.

11. A method of providing changeable illumination of such compact size and low weight as to be suitable for single-handed portable operation by a user, comprising:

providing one or more LEDs having a first characteristic color spectrum output and one or more LEDs having a second characteristic color spectrum output, wherein the first characteristic color spectrum output is different from the second characteristic color spectrum output;

selectively applying pulsed power from a DC voltage source to the LEDs, wherein the pulses are of high-enough frequency such that the human eye does not perceive the pulses; and

changing a pulse characteristic of the pulsed power in order to change a proportion of light output having the first characteristic color spectrum output to that having the second characteristic color spectrum output, wherein the changing of the pulse characteristic maintains an average predetermined light output level of the LED units by sensing a battery voltage and adjusting a pulse characteristic to the LED units based on the measured voltage to maintain an average light output at a predetermined level.

20. The illumination source of claim 11, further comprising a signal-controlling circuit operatively coupled to one or more of the LEDs to generate a visibly interrupted pulse train that includes a coded sequence “

SOS”

in Morse code.

12. A method of providing changeable illumination of such compact size and low weight as to be suitable for single-handed portable operation by a user, comprising:

providing one or more LEDs having a first characteristic color spectrum output and one or more LEDs having a second characteristic color spectrum output, wherein the first characteristic color spectrum output is different from the second characteristic color spectrum output;

selectively applying pulsed power from a DC voltage source to the LEDs, wherein the pulses are of high-enough frequency such that the human eye does not perceive the pulses; and

changing a pulse characteristic of the pulsed power in order to change a proportion of light output having the first characteristic color spectrum output to that having the second characteristic color spectrum output, wherein the changing of the pulse characteristic maintains an average predetermined light output level of the LED units by sensing a light output and adjusting a pulse characteristic to the LED units based on the measured voltage to maintain the average light output at the predetermined level.

13. A portable pulsed LED illumination source of such compact size and low weight as to be suitable for single-handed portable operation by a user, comprising:

one or more LEDs having a first characteristic color spectrum output;

one or more LEDs having a second characteristic color spectrum output, wherein the first characteristic color spectrum output different from the second characteristic color spectrum output;

a housing that holds the one or more LEDs having the first characteristic color spectrum output and the one or more LEDs having the second characteristic color spectrum output, wherein the LED illumination source is configured to project light to illuminate an object separate from the housing;

a battery connector configured to electrically connect to one or more batteries; and

a control circuit that is operatively coupled to receive electrical power from the battery connector and to supply electrical power to the LEDs, and that controls a pulse characteristic to the one or more LEDs having a first characteristic color spectrum output in order to change a proportion of light output having the first characteristic color spectrum output to that having the second characteristic color spectrum output.

14. The illumination source of claim 13, wherein the control circuit increases light output level of the LEDs having a first characteristic color spectrum output by increasing a pulse width.

15. The illumination source of claim 13, wherein the control circuit increases light output level of the LEDs having a first characteristic color spectrum output by increasing a pulse energy.

16. The illumination source of claim 13, wherein the control circuit increases light output level of the LEDs having a first characteristic color spectrum output by increasing a pulse frequency.

17. The illumination source of claim 13, wherein the control circuit increases light output level of the LEDs having a first characteristic color spectrum output by sensing a voltage and adjusting a pulse width based on the sensed voltage.

18. The illumination source of claim 13, wherein the control circuit increases light output level of the LEDs having a first characteristic color spectrum output by sensing a voltage and adjusting a pulse based on the sensed voltage.

19. The illumination source of claim 13, wherein the control circuit increases light output level of the LEDs having a first characteristic color spectrum output by sensing a voltage and adjusting a pulse frequency based on the sensed voltage.

21. The illumination source of claim 13, wherein the control circuit is operatively coupled to the LEDs and selectively applies power pulses from a DC voltage source to the LEDs, the control circuit substantially maintaining an average light output characteristic of the LEDs as a voltage of the voltage source varies over a range that would otherwise vary the light output characteristic by adjusting the pulses, and wherein the light output characteristic that is maintained is light output intensity.

22. The illumination source of claim 21, wherein the control circuit increases light output level of the LEDs having a first characteristic color spectrum output by increasing a pulse width.

23. The illumination source of claim 21, wherein the control circuit increases light output level of the LEDs having a first characteristic color spectrum output by increasing a pulse energy.

24. The illumination source of claim 21, wherein the control circuit increases light output level of the LEDs having a first characteristic color spectrum output by increasing a pulse frequency.

25. The illumination source of claim 21, wherein the control circuit increases light output level of the LEDs having a first characteristic color spectrum output by sensing a voltage and adjusting a pulse width.

26. The illumination source of claim 21, wherein the control circuit increases light output level of the LEDs having a first characteristic color spectrum output by sensing a voltage and adjusting a pulse.

27. The illumination source of claim 21, wherein the control circuit increases light output level of the LEDs having a first characteristic color spectrum output by sensing a voltage and adjusting a pulse frequency.

28. A battery-powered portable pulsed LED illumination source of such compact size and low weight as to be suitable for single-handed portable operation by a user, the source comprising:

one or more LEDs having a first characteristic color spectrum output;

one or more LEDs having a second characteristic color spectrum output, wherein the first characteristic color spectrum output different from the second characteristic color spectrum output;

a housing that holds the one or more LEDs having the first characteristic color spectrum output and the one or more a LEDs having the second characteristic color spectrum output, wherein the housing and the LEDs are configured to project light to illuminate an object;

a switch; and

control means controlled by the switch and operatively coupled to the LEDs for changing a proportion of light output having the first characteristic color spectrum output to that having the second characteristic color spectrum output, wherein the control means drives the LEDs with electrical pulses at a frequency high enough that light produced by the LEDs has an appearance to a human user of being continuous rather than pulsed.

29. The illumination source of claim 28, wherein the control means further comprise:

feedback means for controlling the pulses so that light intensity produced by the LEDs, as perceived by the human user, is substantially constant across a greater range of battery power than a corresponding range for which light intensity is equally constant without the feedback circuit.

30. The illumination source of claim 28, wherein the control means increases light output level of the LEDs having a first characteristic color spectrum output by increasing a pulse width.

31. The illumination source of claim 28, wherein the control means increases light output level of the LEDs having a first characteristic color spectrum output by increasing a pulse energy.

32. The illumination source of claim 28, wherein the control means increases light output level of the LEDs having a first characteristic color spectrum output by increasing a pulse frequency.

33. The illumination source of claim 28, wherein the control means increases light output level of the LEDs having a first characteristic color spectrum output by sensing a voltage and adjusting a pulse width based on the sensed voltage.

34. The illumination source of claim 28, wherein the control means increases light output level of the LEDs having a first characteristic color spectrum output by sensing a voltage and adjusting a pulse based on the sensed voltage.

35. The illumination source of claim 28, wherein the control means increases light output level of the LEDs having a first characteristic color spectrum output by sensing a voltage and adjusting a pulse frequency based on the sensed voltage.

36. A portable pulsed LED illumination source of such compact size and low weight as to be suitable for single-handed portable operation by a user, comprising:

one or more LEDs having a first characteristic color spectrum output;

a user-input switch circuit that receives a light-output-level-setting input indication from a user; and

a control circuit that controls a pulse characteristic of the electrical power to the one or more LEDs having a first characteristic color spectrum output in order to provide user-selectable control of the pulse frequency and/or the pulse width to obtain a reduced apparent brightness due to a change of an “

on”

proportion of light output having the first characteristic color spectrum output based on the light-output-level-setting input.

37. The illumination source of claim 36, further comprising:

one or more LEDs having a second characteristic color spectrum output, wherein the first characteristic color spectrum output is different from the second characteristic color spectrum output, wherein the user-input switch circuit receives a light-output-color-setting input indication from a user and wherein the control circuit changes an overall color spectrum by changing the proportion of light output having the first characteristic color spectrum output to that having the second characteristic color spectrum output based on the light-output-color-setting input.

38. The illumination source of claim 36, further comprising a signal-controlling circuit operatively coupled to one or more of the LEDs to generate a visibly interrupted pulse train that includes a coded sequence “

SOS”

in Morse code.

39. The illumination source of claim 36, wherein the control circuit is operatively coupled to the LEDs and selectively applies power pulses from a DC voltage source to the LEDs, the control circuit substantially maintaining an average light output characteristic of the LEDs as a voltage of the voltage source varies over a range that would otherwise vary the light output characteristic by adjusting the pulses, and wherein the light output characteristic that is maintained is light output intensity.