LED LAMPS AND LED DRIVER CIRCUITS FOR THE SAME

• US 20090161351A1
• Filed: 02/13/2009
• Published: 06/25/2009
• Est. Priority Date: 07/07/2003
• Status: Active Grant

• Current Assignee: Alltemp Products Company Limited (DiversiTech Holdings, Inc.)
• Original Assignee: Brasscop Limited
• Inventors: Klipstein, Donald L., Brass, Jack
• Granted Patent: US 7,950,818 B2
• Time in Patent Office: Days
• US Class Current: 362/157
• CPC Class Codes: F21L 4/005 the device being a pocket lamp F21L4/022, F21L4/045, F21L4/085 take precedence
• CPC Class Codes: F21L 4/027 the light sources being a LED
• CPC Class Codes: F21L 4/06 with the light source coupled to the remainder of the device solely by cable
• CPC Class Codes: F21V 23/0414 specially adapted to be used with portable lighting devices
• CPC Class Codes: F21V 7/0008 providing for indirect lighting
• CPC Class Codes: F21V 7/0075 for portable lighting devices
• CPC Class Codes: F21Y 2113/13 comprising an assembly of point-like light sources
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G01N 21/6447 by visual observation
• CPC Class Codes: H05B 45/32 Pulse-control circuits
• CPC Class Codes: H05B 45/34 Voltage stabilisation; Maintaining constant voltage
• CPC Class Codes: H05B 45/38 using boost topology
• CPC Class Codes: H05B 45/395 Linear regulators
• CPC Class Codes: Y02B 20/30 Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

Abstract

LED lamp has LEDs aimed rearwards with either a concave mirror to the rear of each LED, or one concave mirror to the rear of two or more LEDs, collecting the light from the LEDs to form a forward projecting beam. LEDs may be high power types that require heatsinking. LED lamp may have a lens forward of each LED to collimate the radiation produced by the LEDs into a beam, where at least one lens has at least one aspheric curved surface. LED lamp may have a transparent reflective optic to collimate the radiation produced by each LED into a beam. For an inspection lamp, the LEDs typically have a peak wavelength of 395 to 415 nanometers for seeing the area being irradiated but not so visible as to overwhelm fluorescence of fluorescent materials to be detected. Other wavelengths may be used. LED inspection lamp has a combination of LEDs of different wavelengths or a combination of at least one LED and at least one other light source such that the lamp produces radiation suitable for detection of materials to be detected and adequately illuminates the area being irradiated. LED lamp has LEDs that produce a beam of suitable radiation with a width of 10 degrees or less without additional optics. LED inspection lamp has head attached to a flexible member, with head serving as heatsink for one or more high power LEDs. Current regulator circuits are also disclosed.

Claims

1. A lamp, comprising:

a) a head section that contains one or more light emitting diodes, b) a handle section such that the inspection lamp can be hand held, c) one or more light emitting diodes that produce suitable exciting radiation, d) and a lens forward of each of said light emitting diodes to collimate the exciting radiation into a beam, wherein the lens forward of at least one light emitting diode is aspheric to provide a more sharply focused beam when compared to a lens having one or more spherical surfaces.

2. The lamp of claim 1 wherein each aspheric lens has a surface curve selected from a group consisting of paraboloidal, ellipsoidal, a combination of paraboloidal and spherical, and a combination of paraboloidal and ellipsoidal.

3. The lamp of claim 1 wherein each aspheric lens has a surface curve that is 58% paraboloidal and 42% spherical.

4. The lamp of claim 1 wherein each aspheric lens has a central portion with a radius of curvature of about 9.6 millimeters, and the overall lens thickness is about 4.4 to 5 millimeters, and the refractive index of the lens material is about 1.5.

5. The lamp of claim 1 wherein each aspheric lens has a surface curve defined by an equation with a vertex radius of curvature R where y=(0.58*X²/2R)+(0.42*(R−

SQR(R²−

X²))).

6. The lamp of claim 1 wherein each aspheric lens is selected from a group consisting of planoconvex, biconvex or concavoconvex.

7. The lamp of claim 1 wherein each aspheric lens has a focal length of 35 millimeters with a curve that deviates from a flat surface by the sum, in terms of deviating from a plane, of a spherical surface that alone results in a focal length of 70 millimeters and a paraboloidal surface that alone results in a focal length of 70 millimeters

8. The lamp of claim 1 wherein each aspheric lens is in the form of a fresnel lens.

9. An inspection lamp suitable for the detection of visibly fluorescent materials, the lamp comprising:

an LED that produces radiation suitable for causing fluorescence of said fluorescent materials, wherein the LED is a side emitting type such that its radiation emits mainly into directions within 40 degrees of a plane which an axis of the LED is normal to, and further comprising a reflector to collimate the radiation produced by said LED into a beam.

10. The inspection lamp of claim 9, wherein the lens concentrates the light reflected by the reflector into a converging beam.

11. The inspection lamp of claim 9, further comprising a lens to concentrate the light from the lamp into a converging beam that converges onto an area at a target distance from the inspection lamp.