JP2003504662A - Light collection system - Google Patents

Abstract

(57) Abstract: A light collection system includes a set of paired reflectors having a first or light collection reflector, the first or light collection reflector collecting and collecting radiation emitted from a radiation source. Collimated radiation into a parallel beam, the parallel beam being directed to a portion of a second or condensing or focusing reflector, wherein the second or condensing or focusing reflector is a common beam shared by the two reflectors. Focus the light on the target along the optical axis of An aperture is formed in the second reflector to allow radiation to be transmitted from a source provided at the focal point of the first reflector toward the first reflector, and an aperture is formed in the first reflector to form a second reflector. The radiation reflected and focused by the two reflectors can be transmitted to a target provided at the focal point of the second reflector. A lens having the same focal point and the same common optical axis as the first and second reflectors is positioned between the reflectors to absorb radiation that would otherwise be lost through apertures formed in the respective reflectors. Collect and condense. The entire system inherently generates unit magnification. In addition, retroreflectors may be added to increase the overall flux density at the target. Multiple sets of electromagnetic sources and associated paired reflectors can be cascaded along a common optical axis to increase brightness at the target.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION

The present invention relates to a system for collecting and condensing electromagnetic radiation, such as light, and more particularly to a pair of opposing surfaces for collecting radiation emitted from a radiation source and focusing the collected radiation onto a target. A system using a concave reflector surface.

[0002]

BACKGROUND OF THE INVENTION

The purpose of the system to collect, condense and couple light into a standard waveguide such as a single fiber, fiber bundle or homogenizer is at the target (ie the input end of the waveguide). It is to maximize the brightness of light. Prior art systems with on-axis reflectors and with spherical, elliptical and parabolic reflectors have the advantage of being circularly symmetric. On the other hand, such reflectors inherently reduce the brightness of the light source due to variations in the magnification of light emitted from the source at different angles and striking different parts of the reflecting surface. Off-axis systems that are not circularly symmetric greatly overcome magnification variations and also use spherical, elliptical and parabolic reflectors.

[0003]

[Outline of the Invention]

The present invention includes an apparatus for collecting radiation emitted from an electromagnetic radiation source and condensing the collected radiation onto a target. The apparatus includes a collecting reflector having a concave reflective surface and an opening formed therethrough, and a focusing reflector having a concave reflective surface and an opening formed therethrough. The focusing and focusing reflectors are positioned and oriented in an opposing facing relationship with their respective concave reflecting surfaces.

A focusing reflector is a source of electromagnetic radiation positioned near an aperture formed in the focusing reflector that reflects at least a portion of the electromagnetic radiation through the aperture toward a concave reflecting surface of the focusing reflector. So that it is positioned with respect to the focusing reflector. The focusing reflector directs electromagnetic radiation reflected by the concave reflecting surface of the focusing reflector through an opening formed through the focusing reflector to a target positioned near the opening formed in the focusing reflector. Positioned relative to the focusing reflector, as transmitted.

The focusing reflector reflects at least a portion of the electromagnetic radiation incident on it towards the concave reflecting surface of the focusing reflector, the focusing reflector reflecting the electromagnetic radiation incident on its concave reflecting surface. At least a portion is reflected towards the target through an opening formed in the collection reflector.

The shape of the concave reflecting surface of the focusing and focusing reflector is preferably parabolic. Further, the optical axes of each parabolic reflecting surface are preferably coincident and extend through an aperture formed in the focusing and focusing reflector, the focus of the focusing reflector preferably in the focusing reflector. It is provided close to the formed opening,
The focus of the focusing reflector is preferably located close to the aperture formed in the focusing reflector.

The device may also include a focusing lens disposed between the collection and focusing reflectors. The focusing lens receives a portion of the electromagnetic radiation transmitted through the aperture formed through the focusing reflector and focuses the received electromagnetic radiation through the aperture formed in the focusing reflector.

Sources of electromagnetic radiation such as xenon, metal halides, halogens or mercury arc lamps may or may not be part of the device. Similarly, the target, for example, a waveguide, such as a single optical fiber, fiber bundle or circular or polygonal shaped homogenizer, may or may not include part of the device.

Other features of the present invention will be apparent from consideration of the following description and the appended claims, taken in conjunction with the accompanying drawings, all of which form a part of the specification and the same reference The numbers indicate corresponding parts in the different figures.

Brief Description of the Drawings Exemplary embodiments of the invention are described with reference to the drawings. These examples are illustrative of the principles of this invention and should not be construed as limiting the scope of this invention.

An ideal, paired reflector collecting and condensing system is shown schematically in FIG. 1 and is generally identified by the reference numeral 2. The system 2 comprises a first reflector 10 (also known as a condensing reflector) having a concave reflecting surface 12 and a second reflector 20 also having a concave reflecting surface 22 (also known as a condensing or focusing reflector) 20. Including and The concave reflecting surfaces 12 and 22 are arranged in a facing and facing relationship, preferably both are parabolic in shape. Reflective surface 1
2 and 22 may be coated with any suitable reflective material such as aluminum, silver or a single or multi-layer dielectric coating for use in various color systems such as cold mirrors for visible light. The first reflector 10 has an optical axis 14 on which a focal point 16 lies. Similarly, the second reflector 20
Has an optical axis 24 on which a focal point 26 lies. The first reflector 10 and the second reflector 20 are preferably arranged such that their respective optical axes 14 and 24 coincide with one another. In the ideal system 2 shown in FIG. 1, the electromagnetic radiation source 30 is placed at the focal point 16 of the first reflector 10 and the target 32 is placed at the focal point 26 of the second reflector 20. Radiation emitted by the source 30 is reflected by the concave reflecting surface 12 of the first reflector 10 as collimated radiation towards the concave reflecting surface 22 of the second reflector 20. The radiation is then re-reflected by the concave reflecting surface 22 of the second reflector 20 towards the focus 26 of the second reflector 20 and onto a target 32 placed at the focus 26.

FIG. 1 is a schematic diagram of a cross section of a paired reflector system. In the preferred embodiment, each of the first and second reflectors 10 and 20 is a paraboloid of revolution. Further, as shown in FIG. 1, the first reflecting surface 12 and the second reflecting surface 22
If and are continuous solid surfaces, it is impractical to bring the radiation source into the system, and it is impractical to bring the focused radiation out of the closed system.

FIG. 2 shows a practical implementation of the invention, where the radiation source is an arc lamp 40 placed at the focal point 16 of the first reflector 10 and the target 32 is the reflectors 10 and 20, respectively. Is the input end of a waveguide, such as output fiber 44, placed at the focal point 26 of the second reflector 20 along the common optical axis 14 and 24 of the. An opening 28 is formed in the second reflector 20, through which the radiation emitted by the lamp 40 enters the area between the opposing reflecting surfaces 12 and 22, and the first reflector 1
It hits the 0 reflective surface 12. Aperture 28 is preferably centered about optical axes 14, 24 extending through aperture 28. The radiation in the form of light emitted by the arc lamp 40 is
The second reflector 2 is collected and collimated by the first reflector 10.
Turned to zero. The light is then reflected by the second reflector 20 and condensed or focused onto a target 32 placed at the focal point 26 of the second reflector 20. The aperture 18 is formed in the first reflector 10, and the focused light reflected by the reflecting surface 22 of the second reflector 20 passes through the area between the reflecting surfaces 12 and 22 and is incident on the target 32. Come to do. The opening 18 is preferably
The optical axes 14 and 24 extending through the opening 18 are substantially centered. The first and second reflectors 10, 20 are preferably constructed and arranged such that their respective focal points 16, 26 are provided proximate to corresponding apertures formed in the opposing reflectors. .

Since the spherical retroreflector 42 may be placed on the opposite side of the arc lamp 40,
The light emitted from this side of the arc lamp 40 is reflected back to the arc lamp itself by the retroreflector 42 and then coupled to the paired reflectors 10, 20, thereby increasing the overall brightness of the output of the system. Increase.

Suitable lamps include xenon, metal halide, halogen or mercury arc lamps.

Although a single output fiber 44 is shown in FIG. 3, the target may also include an output fiber bundle, the input end of a homogenizer used to output high power to a low temperature plastic fiber or a homogenizer for a projection television. Good.

The drawbacks of the actual configuration of FIG. 2 are illustrated in FIG. In particular, the aperture 18 formed in the first reflector 10 may necessarily be larger than the focal point 26 and the target 32 of the second reflector 20, so that the source 30 located within the loss cone 46 that delimits the aperture 18. Some of the radiation emitted by is lost. As shown, the opening 18 formed in the first reflector 10 can substantially deprive the reflector 10 of its light collection function in this area, and the amount of loss can be substantial.

FIG. 4 shows the loss cone 46 of light that would be lost due to the openings 28, 18 of the parabolic reflectors 20, 10 respectively disposed between the first and second reflectors 10, 20. The use of a focusing lens 50 to cover is shown. Lens 50 is preferably configured to generate a 1: 1 magnification radiation on a target located at focal point 26. In the embodiment shown in FIG. 4, the target is a fiber bundle 5.
4 is the input end. The combination of reflectors 10, 20 and 42 and focusing lens 50 effectively couples substantially all of the light emitted from arc lamp 40 onto a target located at focus 26. Focusing lens 50 may be a conventional biconvex lens, which may be made of any suitable material such as plastic, glass or quartz. Further, an antireflection film may be applied to the outer surface of the focusing lens 50.

FIG. 4 shows an arc lamp 40, a retroreflector 42, a focusing lens 50, preferably also a parabolic reflector, positioned in the opening 28 of the second reflector 20, which is preferably parabolic. 1 shows an output fiber bundle 54 having an input end positioned within an opening 18 formed in one reflector 10. Light emitted from arc lamp 40 within loss cone 46 defining aperture 18 is collected by lens 50 and focused at unit magnification on the input end of fiber bundle 54 at focus 26. It
The focusing lens 50 preferably coincides with the optical axes 14 and 24 of the first and second reflectors 10, 20 respectively and in a 1: 1 manner the focus 16 of the first and second reflectors 10 and 20, respectively. And 26 are imaged.
The rest of the light emitted by the arc lamp 40 is collected by the first reflector 10 and the retro-reflector 42, and the first reflector 10 causes the second reflector 2 to collect.
Collimated towards 0. The light is then refocused by the second reflector 20 onto the input end of the output fiber bundle 54. The input ends of the arc lamp 40 and the output fiber bundle 54 are respectively connected to the first and second reflectors 10,
20 at focal points 16 and 26 respectively.

To increase the intensity of light incident on the optical target, multiple sources and reflectors can be cascaded so that the outputs of the various sources are combined and focused onto a single target. . Such a system is shown in FIG. Figure 5
Shown are three first or focusing reflectors 10a, 10b and 10c, each having a respective focal point 16a, 16b, 16c and a respective aperture 18a, 18b, 18c formed therein. Similarly, the system includes three second or focusing reflectors 20a, 20b, 20c, each of which has a respective focus 26a, 26b, 26c and a respective aperture 28 formed therein.
a, 28b, 28c. The three sources 30a, 30b, 30c are located at focal points 16a, 16b, 16c, respectively. A retro-reflector 42 may be used in connection with the first source 30a. Second and third sources 30b and 30c are provided at focal points 16b and 16c of reflectors 10b and 10c, respectively. These focal points are the focal points 26a and 26b of the reflectors 20a and 20b, respectively.
Substantially matches. Therefore, the sources 30a, 30b provided on the common optical axis
, 30c outputs are combined and ultimately focused onto the target 60 by the third reflector 20c. The third reflector comprises, in the illustrated embodiment, a homogenizer whose input end is provided at the focal point 26c. Focusing lenses 50a, 50b, in order to minimize losses and further increase intensity at the third focus 26c,
50c are respectively positioned along a common optical axis between the reflectors 10a and 20a, 10b and 20b and 10c and 20c.

FIG. 5 shows a tandem arrangement including three pairs of reflector sets and three focusing lenses. A tandem system may include only two pairs of reflector pairs or more than three pairs of reflector pairs.

As shown in FIGS. 6A-6G, the homogenizer may be circular (FIG. 6A) or rectangular (FIG. 6B), rectangular (FIG. 6C), triangular (FIG. 6D), pentagonal (FIG. 6E), hexagonal. It can be a polygonal shape such as a system (FIG. 6F), an octagon (FIG. 6G) or any other multi-sided shape. Further, the homogenizer can be made from any suitable material such as plastic, glass or quartz.

Although the present invention has been described in relation to what is presently considered the most practical and preferred embodiment, it should not be limited to the disclosed embodiment, as opposed to It is to be understood that it is intended to cover various modifications and equivalents included within the spirit and scope of the appended claims. It is therefore to be understood that changes in the particular parameters used to define the invention can be made without departing from the new aspects of the invention as defined in the appended claims.

[Brief description of drawings]

FIG. 1 is a schematic diagram of an ideal paired reflector system for collecting light from a light source and condensing the collected light at a unity magnification onto a target.

FIG. 2 is a practical paired reflector including an arc lamp, an output fiber, a retroreflector, and an aperture formed in the opposing reflector for receiving light from the arc lamp and transmitting the light to the output fiber. 1 is a schematic diagram of a system.

FIG. 3 is a schematic diagram illustrating the loss of radiant energy through an aperture formed in an opposing reflector for a light source and an output fiber.

FIG. 4 is a schematic diagram illustrating the use of a focusing lens in a paired reflector system to collect radiation that would otherwise be lost through an aperture formed in the reflector. .

FIG. 5 is a schematic diagram of a tandem system in which the outputs of multiple sources are added together to increase brightness at the target.

FIG. 6A is a schematic diagram of a cross-section of multiple polygonal light guide (waveguide) targets that may be used in embodiments of the present invention.

FIG. 6B is a schematic cross-sectional view of a plurality of polygonal light guide (waveguide) targets that may be used in embodiments of the present invention.

FIG. 6C is a schematic cross-sectional view of a plurality of polygonal light guide (waveguide) targets that may be used in embodiments of the present invention.

FIG. 6D is a schematic cross-sectional view of a plurality of polygonal light guide (waveguide) targets that may be used in embodiments of the present invention.

FIG. 6E is a schematic illustration of a cross-section of multiple polygonal light guide (waveguide) targets that may be used in embodiments of the present invention.

FIG. 6F is a schematic cross-sectional view of a plurality of polygonal light guide (waveguide) targets that may be used in embodiments of the present invention.

FIG. 6G is a schematic cross-sectional view of a plurality of polygonal light guide (waveguide) targets that may be used in embodiments of the present invention.

─────────────────────────────────────────────────── ─── Continued front page    (81) Designated countries EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, I T, LU, MC, NL, PT, SE), OA (BF, BJ , CF, CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG), AP (GH, GM, K E, LS, MW, MZ, SD, SL, SZ, TZ, UG , ZW), EA (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), AE, AG, AL, AM, AT, AU, AZ, BA, BB, BG, BR, BY, BZ, C A, CH, CN, CR, CU, CZ, DE, DK, DM , DZ, EE, ES, FI, GB, GD, GE, GH, GM, HR, HU, ID, IL, IN, IS, JP, K E, KG, KP, KR, KZ, LC, LK, LR, LS , LT, LU, LV, MA, MD, MG, MK, MN, MW, MX, MZ, NO, NZ, PL, PT, RO, R U, SD, SE, SG, SI, SK, SL, TJ, TM , TR, TT, TZ, UA, UG, UZ, VN, YU, ZA, ZW (72) Inventor Lopez, Joseph             United States, 91321 California             State, Newhall, Walnut Stori             Auto, 24822 F-term (reference) 2H037 AA03 BA07 CA38 DA03 DA04                 2H087 TA02 TA04 TA06 [Continued summary] The overall bundle density at the get may be increased. Many A common set of electromagnetic sources and associated paired reflectors Columns along the optical axis to increase brightness at the target You can

Claims (28)

[Claims] 1. A source of electromagnetic radiation, a target to be illuminated with at least a portion of the electromagnetic radiation emitted by the source, a concentrating reflector having a concave reflecting surface and an aperture formed therethrough, and a concave reflecting surface. And a focusing reflector having an aperture formed therethrough, said concentrating and focusing reflectors being positioned and oriented in an opposing facing relationship with their respective concave reflecting surfaces, said source Is positioned and directed to direct at least a portion of the electromagnetic radiation emitted thereby toward the concave reflective surface of the focusing reflector through an opening formed through the focusing reflector, the collector Light reflector,
Reflecting at least a portion of the electromagnetic radiation incident thereon toward the concave reflecting surface of the focusing reflector, the focusing reflector focusing at least a portion of the electromagnetic radiation reflected by the concave surface; and Focusing configured and arranged to propagate through an aperture formed through the focusing reflector, the target being transmitted through an aperture that the focusing reflector reflects and formed through the focusing reflector. A device positioned and directed to receive at least a portion of the generated electromagnetic radiation. 2. The apparatus of claim 1, wherein the shape of the concave reflective surface of the focusing and focusing reflector is parabolic. 3. The condensing reflector has an optical axis and a focal point on the optical axis,
The focusing reflector has an optical axis and a focal point on the optical axis, the source is provided proximate to the focal point of the focusing reflector, and the target is proximate to the focal point of the focusing reflector. The apparatus according to claim 1, wherein the apparatus is provided. 4. The apparatus of claim 3, wherein the optical axes of the focusing and focusing reflectors coincide with each other and extend through an aperture formed through the focusing and focusing reflector. 5. The source so as to reflect radiation emitted from the source back toward an aperture formed through the focusing reflector in a direction away from an aperture formed in the focusing reflector. The apparatus of claim 1, further comprising a retroreflector positioned with respect to. 6. A focusing lens further disposed between the focusing and focusing reflectors, the focusing lens being one of electromagnetic radiation transmitted through an aperture formed through the focusing reflector. The apparatus of claim 1, wherein the apparatus is configured and arranged to receive a portion and focus received electromagnetic radiation toward the target through an opening formed in the focusing reflector. 7. The apparatus of claim 6, wherein the focusing lens is made of a material selected from the group consisting of plastic, glass or quartz. 8. The device of claim 6, wherein the focusing lens is coated with an antireflection coating. 9. The condensing reflector has an optical axis and a focal point on the optical axis, and the focusing reflector has an optical axis and a focal point on the optical axis, the condensing and focusing reflector. The optical axes of which coincide with each other and extend through an aperture formed through the focusing and focusing reflector, the focusing lens being aligned with the optical axes of the focusing and focusing reflector. The device of claim 6, comprising: 10. The apparatus of claim 1, wherein the target comprises a waveguide input. 11. The apparatus of claim 10, wherein the waveguide comprises an optical fiber. 12. The apparatus of claim 11, wherein the waveguide comprises a plurality of optical fibers arranged in a fiber bundle. 13. The apparatus of claim 10, wherein the waveguide comprises a homogenizer. 14. The homogenizer has a circular cross-sectional shape.
The apparatus according to item 3. 15. The apparatus according to claim 13, wherein the homogenizer has a polygonal cross-sectional shape. 16. The apparatus of claim 15, wherein the homogenizer has a shape selected from the group consisting of triangles, squares, pentagons, hexagons and octagons. 17. The apparatus of claim 1, wherein the source of electromagnetic radiation comprises an arc lamp. 18. The apparatus of claim 17, wherein the source comprises an arc lamp selected from the group consisting of xenon, metal halides, halogens and mercury arc lamps. 19. Further comprising at least one additional focusing reflector and a corresponding number of additional focusing reflectors, each of said additional focusing and focusing reflectors having an aperture formed therethrough. The light and focusing reflectors are arranged on a common optical axis of the opposite collection-focusing reflector pair and further comprise at least one further electromagnetic radiation source, whereby the total number of said electromagnetic radiation sources is collected. -Corresponding to the total number of pairs of focusing reflectors, and further comprising at least one further focusing lens, whereby the total number of said focusing lenses corresponds to the total number of pairs of focusing-focusing reflectors, said focusing Each of the lenses has an associated collection and focusing of one of the collection-focusing reflector pairs of interest. It is disposed between the Furekuta Apparatus according to claim 6. 20. A device for collecting radiation emitted from an electromagnetic radiation source and condensing the collected radiation onto a target, the apparatus having a concave reflective surface and an opening formed therethrough. A reflector and a second reflector having a concave reflecting surface and an opening formed therethrough, wherein the first and second reflectors are in a relationship in which their respective concave reflecting surfaces face each other. Positioned and directed, the second reflector passes through the opening at least a portion of the electromagnetic radiation emitted by a source positioned proximate to the opening formed through the second reflector. Positioned relative to said first reflector to enable transmission towards said concave reflective surface of said reflector, said first reflector being incident thereon. The first reflector is configured and arranged to reflect at least a portion of the electromagnetic radiation toward the concave reflecting surface of the second reflector, the first reflector being the electromagnetic wave reflected by the concave reflecting surface of the second reflector. To allow at least a portion of the radiation to be transmitted through an opening formed through the first reflector toward a target positioned proximate the opening formed in the first reflector. Positioned relative to the second reflector, the second reflector targeting at least a portion of the electromagnetic radiation incident on the concave reflective surface thereof through an opening formed through the first reflector. An apparatus configured and arranged to focus toward. 21. The device of claim 20, wherein the concave reflecting surfaces of the first and second reflectors are parabolic in shape. 22. The first reflector has an optical axis and a focal point on the optical axis, and the second reflector has an optical axis and a focal point on the optical axis. 21. The apparatus of claim 20, wherein the optical axes of two reflectors are coincident and extend through respective apertures formed in the first and second reflectors. 23. The focus of the first reflector is provided close to an opening formed in the second reflector, and the focus of the second reflector is the first reflector.
23. The apparatus of claim 22, provided proximate an opening formed in the reflector of. 24. A focusing lens disposed between the first and second reflectors, the focusing lens being electromagnetic radiation transmitted through an aperture formed through the second reflector. 21. The apparatus of claim 20, configured and arranged to receive a portion of the received electromagnetic radiation and focus the received electromagnetic radiation through an opening formed in the first reflector. 25. The first reflector has an optical axis and a focal point on the optical axis, and the second reflector has an optical axis and a focal point on the optical axis. The optical axes of two reflectors coincide with each other and extend through an aperture formed through the first and second reflectors, the focusing lens having an optical axis of the first and second reflectors. 25. The device of claim 24, having an optical axis coincident with. 26. A source of electromagnetic radiation, a target to be illuminated with at least a portion of the electromagnetic radiation emitted by the source, a first reflector having a concave reflective surface and an aperture formed therethrough, and a concave reflector. A surface and a second reflector having an opening formed therethrough, the first and second reflectors being positioned and oriented in an opposing facing relationship with their respective concave reflecting surfaces. The source is positioned to transmit at least a portion of the electromagnetic radiation emitted thereby toward the concave reflective surface of the first reflector through an opening formed through the second reflector and And the first reflector reflects at least a portion of the electromagnetic radiation incident thereon onto the concave reflective surface of the second reflector, The second reflector is positioned and oriented such that its concave surface focuses at least a portion of the reflected electromagnetic radiation and transmits through an aperture formed through the first reflector, and the target is The second reflector is positioned and oriented to receive at least a portion of the focused electromagnetic radiation that is reflective and transmitted through an opening formed through the first reflector, and further includes the first and the first A focusing lens disposed between two reflectors, the focusing lens receiving a portion of the electromagnetic radiation transmitted through the aperture formed through the second reflector and the first focusing lens. Constructed and arranged to focus received electromagnetic radiation toward the target through an opening formed in the reflector Apparatus. 27. The apparatus of claim 26, wherein the concave reflective surfaces of the first and second reflectors are parabolic in shape. 28. The first reflector has an optical axis and a focal point on the optical axis, and the second reflector has an optical axis and a focal point on the optical axis. The optical axes of two reflectors coincide with each other and extend through an aperture formed through the first and second reflectors, the focusing lens having an optical axis of the first and second reflectors. 27. The device of claim 26, having an optical axis coincident with.