WO2001007958A1 - Light collimating and distributing apparatus - Google Patents

Light collimating and distributing apparatus Download PDF

Info

Publication number
WO2001007958A1
WO2001007958A1 PCT/US2000/040445 US0040445W WO0107958A1 WO 2001007958 A1 WO2001007958 A1 WO 2001007958A1 US 0040445 W US0040445 W US 0040445W WO 0107958 A1 WO0107958 A1 WO 0107958A1
Authority
WO
WIPO (PCT)
Prior art keywords
lens
light
combination
aspheric lens
drum
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/US2000/040445
Other languages
French (fr)
Inventor
Vladimir Medvedev
William A. Parkyn, Jr.
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Teledyne Lighting and Display Products Inc
Original Assignee
Teledyne Lighting and Display Products Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Teledyne Lighting and Display Products Inc filed Critical Teledyne Lighting and Display Products Inc
Priority to EP00960176A priority Critical patent/EP1264207A1/en
Priority to JP2001512991A priority patent/JP2003505737A/en
Priority to CA2379831A priority patent/CA2379831C/en
Publication of WO2001007958A1 publication Critical patent/WO2001007958A1/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B3/00—Simple or compound lenses
    • G02B3/02—Simple or compound lenses with non-spherical faces
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/1336—Illuminating devices
    • G02F1/133602—Direct backlight
    • G02F1/133606—Direct backlight including a specially adapted diffusing, scattering or light controlling members
    • G02F1/133607—Direct backlight including a specially adapted diffusing, scattering or light controlling members the light controlling member including light directing or refracting elements, e.g. prisms or lenses

Definitions

  • This invention relates generally to efficient illumination of targets, as for example screens, such as liquid crystal displays.
  • a yet further object is to provide a target spaced forwardly of the aspheric lens and reflector, the target positioned to receive collimated light via the aspheric lens and reflector.
  • the target may advantageously comprise a liquid crystal display.
  • Fig. 1 is a view in section of a light source, drum lens, and reflector, incorporating the invention
  • Fig. 2 is a view like Fig. 1 but also showing a modified aspheric lens
  • a light source 101 is shown as radiating light over an angular range 110, as defined between an optical axis 107 extending forwardly in direction 108, and a rearwardly and laterally extending ray 109.
  • the source may comprise a plasma lamp.
  • a central aspheric lens 103 is located forwardly, i.e. above, the source, and axis 107 centrally intersects lens 103, which extends about axis 107. That lens has an inner rearwardly convex surface indicated at 103a, and an outer, forwardly convex surface indicated at 103b. In a plane normal to that of Fig.
  • the refracted rays are compressed, (compare the relatively larger angle formed between uppermost and lowermost rays 119 and 120' entering surface 104a, with the relatively reduced angle formed between corresponding uppermost and lowermost rays 119a and 120a exiting drum lens surface 104b).
  • the rays exiting surface 104b pass to a reflector 125 that extends annularly about the optical axis, and the rays are reflected forwardly to form the outer annular beam 130, with uniform illuminance and therefore constant angular beam width and maximal collimation. Efficient collimation with minimum lens system depth are also provided. Annular gap 133 exists between beams 130 and 121.
  • the surface line of the reflector 125 has a shallow outward facing S- shape, in the plane of Fig. 1 (i.e. with shallow convexity at 125a, and shallow concavity at 125b.
  • the annular areas between successive collimated rays, as at 160 and 161, and 170 and 171, for example are equal.
  • the reflector edge 158 may have a substantially rectangular or square outline in planes normal to Fig. 1.
  • the device may be provided with a protective transparent envelope or shell 140 extending about the light source. See envelope end wall 140a through which light rays pass to the lens 103, and envelope side wall 140b through which light rays pass to the drum lens.
  • a correction lens 190 may be located forwardly of the lenses 103 and 104, as seen in Fig. 3, i.e. between the latter lenses and a target 191.
  • the target may consist of a liquid crystal display (LCD).
  • the system with correction lens has a non-circularly symmetric version, wherein the cross-section in Fig. 1 varies somewhat with azimuth angle about the source.
  • typical LCDs have a 4:3 aspect ratio, so that they intercept only 61 % of the circular output beam.
  • the rectangular output from a non-circularly symmetric version of the system will have greatly increased output illuminance.
  • the transparent material of the lenses and envelope may consist of glass or plastic.
  • the device as shown and described may be regarded as a preferred form.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Devices For Indicating Variable Information By Combining Individual Elements (AREA)
  • Projection Apparatus (AREA)
  • Lenses (AREA)
  • Non-Portable Lighting Devices Or Systems Thereof (AREA)

Abstract

In a device for directing light longitudinally forwardly, the combination comprises a light source (101), a drum lens (104) having a body extending about the light source, for refracting light from the source; a light reflector (125) extending about the drum lens body for forwardly re-directing refracted light received from the drum lens body, the drum lens and reflector defining a longitudinally forwardly of the light source to refract light received from the source to be transmitted in a forward direction.

Description

LIGHT COLLIMATING AND DISTRIBUTING APPARATUS
BACKGROUND OF THE INVENTION
This invention relates generally to efficient illumination of targets, as for example screens, such as liquid crystal displays.
There is need for devices of the type disclosed herein, and in particular for uniform illumination of targets, using compact high-brightness light sources.
Also, there is need for light collimating devices that have minimum lens and reflector total depth, along the optical axis, and with maximum interception of light from a central source.
SUMMARY OF THE INVENTION
It is a major object of the invention to provide an improved device of the type referred to and comprising, in combination: a light source, b) a drum lens having a body extending about the light source, for refracting light from the source, c) a light reflector extending about the drum lens body, for forwardly re-directing refracted light received from the drum lens body, d) the drum lens and reflector defining a longitudinally forwardly extending optical axis, e) and including an aspheric lens located longitudinally forwardly of the light source to refract light received from said source to be transmitted in a forward direction.
As will be seen, the optical axis centrally intersects the aspheric lens. It is a further object of the invention to provide a protective, transparent envelope extending about the light source, the drum lens extending laterally about the envelope, and the aspheric lens extending longitudinally forwardly of the envelope to receive light from the source via the envelope and to collimate such light. The aspheric lens may be integral with the drum lens, with a forwardly facing land located between the drum lens and the aspheric lens.
Yet another object is to provide such an aspheric lens with an inner surface longitudinally facing the envelope, the inner surface having rearward convexity, and the aspheric lens also having an outer surface longitudinally facing away from the envelope, that outer surface having forward convexity which exceeds the convexity of the inner surface.
An additional object is to provide a local juncture between the drum lens and the aspheric lens, and located to separate light refracted by the drum lens and the aspheric lens, whereby a gap is formed between light refracted by the aspheric lens and light reflected by the reflector. As will be seen, the drum lens may advantageously have an inner substantially cylindrical surface intercepting an edge defined by said aspheric lens inner surface. Also, the drum lens may have an outer outwardly convex surface terminating outwardly of an edge defined by the aspheric lens outer surface.
A yet further object is to provide a target spaced forwardly of the aspheric lens and reflector, the target positioned to receive collimated light via the aspheric lens and reflector. The target may advantageously comprise a liquid crystal display.
A related U.S. application is Serial No. 08/864,840, filed May 29, 1997. These and other objects and advantages of the invention, as well as the details of an illustrative embodiment, will be more fully understood from the following specification and drawings, in which: DRAWING DESCRIPTION
Fig. 1 is a view in section of a light source, drum lens, and reflector, incorporating the invention; Fig. 2 is a view like Fig. 1 but also showing a modified aspheric lens; and
Fig. 3 is a view like Fig. 1, but also showing a corrective lens.
DETAILED DESCRIPTION
In Fig. 1 , a light source 101 is shown as radiating light over an angular range 110, as defined between an optical axis 107 extending forwardly in direction 108, and a rearwardly and laterally extending ray 109. The source may comprise a plasma lamp. A central aspheric lens 103 is located forwardly, i.e. above, the source, and axis 107 centrally intersects lens 103, which extends about axis 107. That lens has an inner rearwardly convex surface indicated at 103a, and an outer, forwardly convex surface indicated at 103b. In a plane normal to that of Fig. 1, and passing through axis 107, the surfaces 103a and 103b may have curvatures 103a' and 103b' different from those seen in Fig. 1. See Fig. 2 in this regard, showing less curvatures at 103a' and 103b' than exist at surfaces 103a and 103b, the curvatures gradually changing between the Fig. 1 and Fig. 2 planes. Another possible aspheric lens has curvatures of surfaces as in either of Figs. 1 and 2 which are not spherical, but which are surfaces of revolution about the optical axis. The light rays in bundle 120 that are refracted by lens 103 are collimated into central beam 121.
Also shown in Figs. 1 and 2 is a drum lens 104 having a body located sidewardly, or laterally of the light source and the optical axis. The drum lens body also extends about the light source and the optical axis, for refracting light from the source, the refracted light rays indicated at 118. The drum lens has an inner generally cylindrical surface seen at 104a, and an outer, outwardly convex outer surface 104b, that surface also being convex in planes normal to the optical axis and intersecting the surface 104b. The refracted rays are compressed, (compare the relatively larger angle formed between uppermost and lowermost rays 119 and 120' entering surface 104a, with the relatively reduced angle formed between corresponding uppermost and lowermost rays 119a and 120a exiting drum lens surface 104b).
The rays exiting surface 104b, pass to a reflector 125 that extends annularly about the optical axis, and the rays are reflected forwardly to form the outer annular beam 130, with uniform illuminance and therefore constant angular beam width and maximal collimation. Efficient collimation with minimum lens system depth are also provided. Annular gap 133 exists between beams 130 and 121.
The surface line of the reflector 125 has a shallow outward facing S- shape, in the plane of Fig. 1 (i.e. with shallow convexity at 125a, and shallow concavity at 125b. The annular areas between successive collimated rays, as at 160 and 161, and 170 and 171, for example are equal. The reflector edge 158 may have a substantially rectangular or square outline in planes normal to Fig. 1.
The device may be provided with a protective transparent envelope or shell 140 extending about the light source. See envelope end wall 140a through which light rays pass to the lens 103, and envelope side wall 140b through which light rays pass to the drum lens.
The aspheric lens 103 and the drum lens may be integral, or of unitary construction; and a forwardly facing flat land 180 is formed between the outermost edge 103d of lens 103, and the uppermost edge 104d of lens 104. That land may have lateral length that varies with the curvature of the lens surface 103b.
A correction lens 190 may be located forwardly of the lenses 103 and 104, as seen in Fig. 3, i.e. between the latter lenses and a target 191. The target may consist of a liquid crystal display (LCD).
The system with correction lens has a non-circularly symmetric version, wherein the cross-section in Fig. 1 varies somewhat with azimuth angle about the source. For example, typical LCDs have a 4:3 aspect ratio, so that they intercept only 61 % of the circular output beam. Thus the rectangular output from a non-circularly symmetric version of the system will have greatly increased output illuminance.
The transparent material of the lenses and envelope may consist of glass or plastic. The device as shown and described may be regarded as a preferred form.

Claims

1. In a device for directing light longitudinally forwardly, the combination comprising: a light source, b) a drum lens having a body extending about the light source, for refracting light from the source, c) a light reflector extending about the drum lens body for forwardly re-directing refracted light received from the drum lens body, d) said drum lens and reflector defining a longitudinally forwardly extending optical axis, e) and including an aspheric lens located longitudinally forwardly of the light source to refract light received from said source to be transmitted in a forward direction.
2. The combination of claim 1 wherein said optical axis centrally intersects said aspheric lens.
3. The combination of claim 1 including a protective, transparent envelope extending about the light source, said drum lens extending laterally about said envelope, and said aspheric lens extending longitudinally forwardly of the envelope to receive light from the source via the envelope and to collimate said light.
4. The combination of claim 1 wherein the aspheric lens is integral with the drum lens, there being a forwardly facing land located between the drum lens and the aspheric lens.
5. The combination of claim 3 wherein the aspheric lens has an inner surface longitudinally facing the envelope, said inner surface having rearward convexity, and said aspheric lens has an outer surface longitudinally facing away from the envelope, said outer surface having forward convexity which exceeds the convexity of said inner surface.
6. The combination of claim 3 wherein there is a local juncture between the drum lens and the aspheric lens, and located to separate light refracted by the drum lens and the aspheric lens, whereby a gap is formed between light refracted by the aspheric lens and light reflected by the reflector.
7. The combination of claim 5 wherein the drum lens has an inner substantially cylindrical surface intercepting an edge defined by said aspheric lens inner surface.
8. The combination of claim 7 wherein said drum lens has an outer outwardly convex surface terminating outwardly of an edge defined by said aspheric lens outer surface.
9. The combination of claim 1 including a target spaced forwardly of said aspheric lens and said reflector, said target positioned to receive collimated light via said aspheric lens and said reflector.
10. The combination of claim 7 including a target spaced forwardly of said aspheric lens and reflector, said target positioned to receive uniformly collimated light via said aspheric lens and reflector.
11. The combination of claim 9 wherein said target comprises a liquid crystal display.
12. The combination of claim 10 wherein said target comprises a liquid crystal display.
13. The combination of claim 1 wherein the source is a plasma lamp.
PCT/US2000/040445 1999-07-22 2000-07-21 Light collimating and distributing apparatus Ceased WO2001007958A1 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
EP00960176A EP1264207A1 (en) 1999-07-22 2000-07-21 Light collimating and distributing apparatus
JP2001512991A JP2003505737A (en) 1999-07-22 2000-07-21 Light collimation and distribution device
CA2379831A CA2379831C (en) 1999-07-22 2000-07-21 Light collimating and distributing apparatus

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US09/359,620 1999-07-22
US09/359,620 US6181476B1 (en) 1999-07-22 1999-07-22 Light collimating and distributing apparatus

Publications (1)

Publication Number Publication Date
WO2001007958A1 true WO2001007958A1 (en) 2001-02-01

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ID=23414623

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2000/040445 Ceased WO2001007958A1 (en) 1999-07-22 2000-07-21 Light collimating and distributing apparatus

Country Status (5)

Country Link
US (1) US6181476B1 (en)
EP (1) EP1264207A1 (en)
JP (1) JP2003505737A (en)
CA (1) CA2379831C (en)
WO (1) WO2001007958A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2992738A1 (en) * 2012-06-29 2014-01-03 Peugeot Citroen Automobiles Sa METHOD FOR DEFINING AN ASPHERIC LENS AND LIGHTING MODULE COMPRISING SUCH A LENS FOR A MOTOR VEHICLE PROJECTOR
EP2927727A1 (en) * 2014-04-03 2015-10-07 Whelen Engineering Company, Inc. Wide Angle Optical System for LED Array

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US6560038B1 (en) 2001-12-10 2003-05-06 Teledyne Lighting And Display Products, Inc. Light extraction from LEDs with light pipes
US7021801B2 (en) 2002-09-19 2006-04-04 Everbrite, Llc High-intensity directional light
US6896381B2 (en) * 2002-10-11 2005-05-24 Light Prescriptions Innovators, Llc Compact folded-optics illumination lens
US7042655B2 (en) * 2002-12-02 2006-05-09 Light Prescriptions Innovators, Llc Apparatus and method for use in fulfilling illumination prescription
US6924943B2 (en) * 2002-12-02 2005-08-02 Light Prescriptions Innovators, Llc Asymmetric TIR lenses producing off-axis beams
US7377671B2 (en) 2003-02-04 2008-05-27 Light Prescriptions Innovators, Llc Etendue-squeezing illumination optics
US8075147B2 (en) * 2003-05-13 2011-12-13 Light Prescriptions Innovators, Llc Optical device for LED-based lamp
US7021797B2 (en) * 2003-05-13 2006-04-04 Light Prescriptions Innovators, Llc Optical device for repositioning and redistributing an LED's light
US7329029B2 (en) * 2003-05-13 2008-02-12 Light Prescriptions Innovators, Llc Optical device for LED-based lamp
WO2005012951A2 (en) * 2003-07-28 2005-02-10 Light Prescriptions Innovators, Llc Three-dimensional simultaneous multiple-surface method and free-form illumination-optics designed therefrom
WO2005012952A2 (en) * 2003-07-29 2005-02-10 Light Prescriptions Innovators, Llc Circumferentially emitting luminaires and lens elements formed by transverse-axis profile-sweeps
US7495837B2 (en) * 2005-01-31 2009-02-24 Avago Technologies General Ip (Singapore) Pte. Ltd Collimating lens structures
US8419232B2 (en) * 2005-07-28 2013-04-16 Light Prescriptions Innovators, Llc Free-form lenticular optical elements and their application to condensers and headlamps
JP2009503793A (en) * 2005-07-28 2009-01-29 ライト プレスクリプションズ イノベーターズ エルエルシー Etendue-conserving illumination optics for backlights and frontlights
US8631787B2 (en) * 2005-07-28 2014-01-21 Light Prescriptions Innovators, Llc Multi-junction solar cells with a homogenizer system and coupled non-imaging light concentrator
WO2008008994A2 (en) * 2006-07-14 2008-01-17 Light Prescriptions Innovators, Llc Brightness-enhancing film
WO2008022064A2 (en) * 2006-08-10 2008-02-21 Light Prescriptions Innovators, Llc Led light recycling device
WO2008022065A2 (en) * 2006-08-11 2008-02-21 Light Prescriptions Innovators, Llc Led luminance-enhancement and color-mixing by rotationally multiplexed beam-combining
CN102016402A (en) * 2008-02-21 2011-04-13 光处方革新有限公司 Spherically emitting remote phosphor
JP6552710B2 (en) * 2016-02-22 2019-07-31 三菱電機株式会社 Laser light source device and method of manufacturing laser light source device

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US5926320A (en) * 1997-05-29 1999-07-20 Teldedyne Lighting And Display Products, Inc. Ring-lens system for efficient beam formation

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US4770514A (en) * 1986-11-21 1988-09-13 David Silverglate Collimating compound catoptric immersion lens
US5577493A (en) * 1992-04-16 1996-11-26 Tir Technologies, Inc. Auxiliary lens to modify the output flux distribution of a TIR lens
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2992738A1 (en) * 2012-06-29 2014-01-03 Peugeot Citroen Automobiles Sa METHOD FOR DEFINING AN ASPHERIC LENS AND LIGHTING MODULE COMPRISING SUCH A LENS FOR A MOTOR VEHICLE PROJECTOR
WO2014001687A1 (en) * 2012-06-29 2014-01-03 Peugeot Citroen Automobiles Sa Method for defining an aspherical lens and lighting module for a motor vehicle headlight comprising such a lens
EP2927727A1 (en) * 2014-04-03 2015-10-07 Whelen Engineering Company, Inc. Wide Angle Optical System for LED Array
US9528679B2 (en) 2014-04-03 2016-12-27 Whelen Engineering Company, Inc. Wide angle optical system for LED array

Also Published As

Publication number Publication date
EP1264207A4 (en) 2002-12-11
JP2003505737A (en) 2003-02-12
CA2379831A1 (en) 2001-02-01
CA2379831C (en) 2010-09-28
EP1264207A1 (en) 2002-12-11
US6181476B1 (en) 2001-01-30

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