Luminaire

• US 6,478,453 B2
• Filed: 01/03/2001
• Issued: 11/12/2002
• Est. Priority Date: 01/07/2000
• Status: Expired due to Term

• Current Assignee: Signify Holding B.V. (Signify N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Van Hees, Antonius Johannes Maria, Maas, Theodorus Franciscus Mattheus Maria, Ansems, Johannes Petrus Maria, Lammers, Liane
• Primary Examiner(s): O'Shea, Sandra
• Assistant Examiner(s): TRUONG, BAO Q
• Application Number:
  US09/754,170
• Publication Number:
  US 20010007527A1
• Time in Patent Office: 678 Days
• Field of Search: 362/294, 362/373, 362/327, 362/334, 362/335, 362/253, 362/268, 362/331, 362/309, 359/443, 359/448, 359/223, 359/455, 359/456, 359/457, 353/22, 353/23, 353/24, 353/29, 353/95, 353/97, 353/84
• US Class Current: 362/294
• CPC Class Codes: F21S 6/002 Table lamps, e.g. for ambient lighting
• CPC Class Codes: F21V 14/06 by movement of refractors in vehicle head lamps F21S41/635
• CPC Class Codes: F21V 21/06 Bases for movable standing lamps; Fixing standards to the bases F21V21/08 takes precedence
• CPC Class Codes: F21V 29/74 with fins or blades
• CPC Class Codes: F21V 29/767 the planes containing the fins or blades having directions perpendicular to the light emitting axis
• CPC Class Codes: F21V 5/008 Combination of two or more successive refractors along an optical axis
• CPC Class Codes: F21V 5/048 the lens being a simple lens adapted to cooperate with a point-like source for emitting mainly in one direction and having an axis coincident with the main light transmission direction, e.g. convergent or divergent lenses, plano-concave or plano-convex lenses
• CPC Class Codes: F21V 7/0091 using total internal reflection
• CPC Class Codes: F21W 2131/406 for theatres, stages or film studios
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02B 19/0028 refractive and reflective surfaces, e.g. non-imaging catadioptric systems
• CPC Class Codes: G02B 19/0061 the light source comprising a LED semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission H01L33/00
• CPC Class Codes: G02B 27/0944 Diffractive optical elements, e.g. gratings, holograms gratings per se G02B5/18; holograms used as optical elements per se G02B5/32
• CPC Class Codes: G02B 27/425 in illumination systems mask illumination systems in photolithographic systems G03F7/70158
• CPC Class Codes: G03B 21/2033 LED or laser light sources
• CPC Class Codes: G03B 21/208 Homogenising, shaping of the illumination light

Abstract

A luminaire for projecting an image comprises a housing (1) having a light emission window (2). The housing (1) accommodates a light source (3), an optical system (4) for directing light originating from the light source (3) along a longitudinal axis (5), and an image-forming surface (6) which is positioned orthogonally with respect to the longitudinal axis (5). According to the invention, the light source is a LED (3), and the optical system (4) comprises a collimating element (14) for collimating the light originating from the LED (3). Preferably, the luminaire comprises only one LED (3) which, during operation, has a luminous flux of at least 5 lm. Preferably, the housing (1) also comprises a focusing lens (15) for focusing the collimated light originating from the collimating element (14) on the image-forming surface (6) and, preferably, a projection lens (7, 7′) for projecting an image of the image-forming surface (6). Preferably, parts of the collimating element show total internal reflection. The luminaire according to the invention is a compact, lightweight, low-energy and low-maintenance luminaire.

Claims

1. A luminaire for projecting an image by means of a light beam, comprising:

a housing which accommodates a light source and an optical system for directing the radiation to be generated by the light source along a longitudinal axis,

an image-forming surface which is to be placed in the light beam transversely to the longitudinal axis,

the light source comprising at least one light-emitting diode,

the optical system including a synthetic resin collimating element for collimating the light beam, and

the light-emitting diode being mounted on a metal-core printed circuit board.

2. A luminaire as claimed in claim 1, wherein the light source is composed of a single light-emitting diode, the luminous flux of which is at least 5 lm during operation.

3. A luminaire as claimed in claim 1, wherein parts of the collimating element exhibit total internal reflection.

4. A luminaire as claimed in claim 1, wherein a surface of the collimating element facing away from the light-emitting diode is curved.

5. A luminaire as claimed in claim 1, wherein the optical system further comprises a focusing lens to focus the collimated light beam on the image-forming surface.

6. A luminaire as claimed in claim 5, wherein the collimating element and the focusing lens jointly form an integrated whole.

7. A luminaire as claimed in claim 5, wherein the focusing lens is a Fresnel lens.

8. A luminaire as claimed in claim 1, wherein the luminaire comprises a projection lens for projecting an image of the image-forming surface.

9. A luminaire as claimed in claim 8, wherein the projection lens is a Fresnel lens.

10. A luminaire as claimed in claim 1, wherein

the housing is made of metal and provided with cooling fins, and

in that the metal-core printed circuit board is in contact with the metal housing via a heat-conducting connection.

11. A luminaire as claimed in claim 1, wherein the luminaire comprises control electronics for changing the luminous flux of the light-emitting diode.

12. A luminaire as claimed in claim 1, wherein the collimating element is in contact with the light source.

13. A luminaire for projecting an image by a light beam, comprising:

a housing having a light-emitting diode and an optical system for directing light generated by the light-emitting diode,

an image-forming surface located along the light beam,

said optical system including a collimating element for collimating the light and a focusing lens for focusing the light and forming the light beam,

said collimating element being located between the light-emitting diode and the image-forming surface, and

the light-emitting diode being mounted on a metal-core printed circuit board.

14. A luminaire as claimed in claim 13, wherein said collimating element has a first side facing said light-emitting diode and a second side facing away from said light-emitting diode and opposite said first side, said first side having a first portion with a first curvature and a second portion with a second curvature which is different from said first curvature.

15. A luminaire as claimed in claim 13, wherein said collimating element has a first side, said first side having a first portion with a first curvature and a second portion with a second curvature which is different from said first curvature.

16. A luminaire as claimed in claim 15, wherein said first side is facing said light-emitting diode, and wherein the collimating element has a second side opposite said first side and facing away from said light-emitting diode, said second side having a first portion with a first curvature and a second portion with a second curvature which is different from said first curvature.

17. A luminaire as claimed in claim 13, wherein parts of the collimating element exhibit total internal reflection.

18. A luminaire as claimed in claim 13, wherein the collimating element and the focusing lens jointly form an integrated whole.

19. A luminaire as claimed in claim 13, wherein the luminaire comprises control electronics for changing the luminous flux of the light-emitting diode.

20. A luminaire for projecting an image by a light beam, comprising:

a housing having a light-emitting diode and an optical system for directing light generated by the light-emitting diode, and

an image-forming surface located along the light beam,

said optical system including a collimating element for collimating the light and a focusing lens for focusing the light and forming the light beam, and

said collimating element being in contact with the light-emitting diode.