US3817605A - Behind mirror focus light gathering device - Google Patents

Behind mirror focus light gathering device Download PDF

Info

Publication number
US3817605A
US3817605A US00340096A US34009673A US3817605A US 3817605 A US3817605 A US 3817605A US 00340096 A US00340096 A US 00340096A US 34009673 A US34009673 A US 34009673A US 3817605 A US3817605 A US 3817605A
Authority
US
United States
Prior art keywords
shell
smaller
larger
inlet
sun
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.)
Expired - Lifetime
Application number
US00340096A
Inventor
C Franklin
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.)
Individual
Original Assignee
Individual
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 Individual filed Critical Individual
Priority to US00340096A priority Critical patent/US3817605A/en
Application granted granted Critical
Publication of US3817605A publication Critical patent/US3817605A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23QIGNITION; EXTINGUISHING-DEVICES
    • F23Q13/00Igniters not otherwise provided for
    • F23Q13/005Igniters not otherwise provided for using light, e.g. sunlight or laser
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24SSOLAR HEAT COLLECTORS; SOLAR HEAT SYSTEMS
    • F24S23/00Arrangements for concentrating solar-rays for solar heat collectors
    • F24S23/70Arrangements for concentrating solar-rays for solar heat collectors with reflectors
    • F24S23/79Arrangements for concentrating solar-rays for solar heat collectors with reflectors with spaced and opposed interacting reflective surfaces
    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B19/00Condensers, e.g. light collectors or similar non-imaging optics
    • G02B19/0004Condensers, e.g. light collectors or similar non-imaging optics characterised by the optical means employed
    • G02B19/0019Condensers, e.g. light collectors or similar non-imaging optics characterised by the optical means employed having reflective surfaces only (e.g. louvre systems, systems with multiple planar reflectors)
    • G02B19/0023Condensers, e.g. light collectors or similar non-imaging optics characterised by the optical means employed having reflective surfaces only (e.g. louvre systems, systems with multiple planar reflectors) at least one surface having optical power
    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B19/00Condensers, e.g. light collectors or similar non-imaging optics
    • G02B19/0033Condensers, e.g. light collectors or similar non-imaging optics characterised by the use
    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B19/00Condensers, e.g. light collectors or similar non-imaging optics
    • G02B19/0033Condensers, e.g. light collectors or similar non-imaging optics characterised by the use
    • G02B19/0038Condensers, e.g. light collectors or similar non-imaging optics characterised by the use for use with ambient light
    • G02B19/0042Condensers, e.g. light collectors or similar non-imaging optics characterised by the use for use with ambient light for use with direct solar radiation
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00Energy generation through renewable energy sources
    • Y02E10/40Solar thermal energy, e.g. solar towers

Definitions

  • ABSTRACT A device for converging sunlight beams so to be able to ignite a fire or do solar cooking; the device consisting of a cylinder of frusto-conica, shape which is outwardly arcuate, the cylinder inner surface forming a reflector of the light beams so that when positioned with its axis parallel to the light beams, and with its wider mouth end toward the sun, the light rays reflected from the inner surface pass out the rear smaller mouth and the light rays converge together at a point rearward of the small mouth.
  • This invention relates generally to light focusing devices. More specifically it relates to devices for concentrating light rays.
  • a principal object of the present invention is to provide a light gathering device which can start a fire or do solar cooking by utilizing sun light rays.
  • Another object is to provide a light gathering device inwhich the sun rays are gathered to a commont point that is located rearwardly or behind the device, thus differing from reflectors where such point is forwardly thereof.
  • Another object is to provide a light gathering device which can be made in any of various sizes, and which for practical purpose can be small so that it is convenient to be carried in a pocket by a sportsman or scout out-of-doors.
  • FIG. 1 is a perspective view of the invention shown in use.
  • FIG. 2 is a cross section on line 2-2 of FIG. 1.
  • FIG. 3 is a top view of the device.
  • FIG. 4 is a view similar to FIG. 2 and showing a modified design that includes a central cone for reflecting central light rays so to be more efficient by utilizing all the rays that otherwise would pass through the center opening without benefit.
  • FIG. 5 is a top view thereof.
  • the reference numeral represents a behind mirror focus light gathering device according to the present invention, wherein there is a one piece shell 11 that consists only of a side wall around a central opening 12.
  • the shell wall is of frusto-conical shape which is outwardly bulged or arcuate.
  • the inner surface 13 thereof is mirror polished so to reflect light rays with maximum efficiency.
  • the longitudinal axis of the device is made parallel to sun light rays 14 and the large mouth 15 of opening 12 is positioned toward the direction of the sun.
  • direct light rays 14 from the sun strike the surface 13 from which they reflect as reflected light rays 16 that pass outward of small mouth 17 of the opening 12, the reflected light rays 16 crossing each other at a point 18 that is rearwardly a distance away from the device 10. If the point 18 is located on a firewood 19 (as shown in FIG. 1), the concentrated light rays will be sufficient to ignite the same.
  • FIGS. 4 and 5 a modified design of the device 20 is shown which includes the structure of above described device 10, and which additionally includes a concentric central conical shell 21 secured rigidly to shell 11 by means of three radial, thin fins 22 therebetween.
  • the shell is positioned within the mouth 15 of shell 11 and has its conically pointed end 23 in a direction toward the sun.
  • the side wall of the shell is outwardly bulged or arcuate, and the outer surface 24 thereof is mirror polished for maximum reflective efficiency.
  • the outer diameter of the base end 25 of the shell 21 is a same size as the mouth 17 so to utilize all the light rays entering the device without blocking any of the surface 13 from the direct sun rays.
  • the shells 11 and 21 when viewed in a horizontal cross section, such as in FIG. 4 may have the arcuate bulges thereof either elliptical or circular about a constant point.
  • a mirror device for focusing sun rays at a predetermined point comprising a larger shell having an inner concave reflecting arcuate surface, said shell having a circular inlet opening of larger diameter tapering to a concentric sun ray outlet opening of smaller diameter whereby the inner surface curves regularly in a longitudinal direction from the larger inlet opening to the smaller outlet opening forming a surface that reflects sun rays entering the inlet opening to a focal point outward of the outlet opening in combination with a smaller second shell having an arcuate convex outer surface which curves regularly from a point to an open circular end, said smaller shell being affixed concentrically within the larger shell by spaced radial fins wherein the point of the smaller shell projects towards the sun and beyond the inlet opeing of the larger shell, with the large end the smaller shell positioned between the inlet and outlet openings of the larger shell.

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Optics & Photonics (AREA)
  • General Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Combustion & Propulsion (AREA)
  • Chemical & Material Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Sustainable Development (AREA)
  • Health & Medical Sciences (AREA)
  • Toxicology (AREA)
  • Sustainable Energy (AREA)
  • Thermal Sciences (AREA)
  • Optical Elements Other Than Lenses (AREA)

Abstract

A device for converging sunlight beams so to be able to ignite a fire or do solar cooking; the device consisting of a cylinder of frusto-conica, shape which is outwardly arcuate, the cylinder inner surface forming a reflector of the light beams so that when positioned with its axis parallel to the light beams, and with its wider mouth end toward the sun, the light rays reflected from the inner surface pass out the rear smaller mouth and the light rays converge together at a point rearward of the small mouth.

Description

United States Patent [191 Franklin et al.
June 18, 1974 BEHIND MIRROR FOCUS LIGHT GATHERING DEVICE [76] Inventors: Chester A. Franklin, c/o George Spector, 3615 Woolworth Bldg, 233 Broadway; George Spector, 3615 Woolworth Bldg, 233 Broadway, both of New York, NY. 10017 22 Filed: Mar. 12, 1973 21 Appl. No.: 340,096
[52] US. Cl 350/294, 350/199, 350/288 [51] Int. Cl. G02b 5/10 [58] Field of Search 350/288, 299, 293, 294,
[56] References Cited UNITED STATES PATENTS 2/1914 Boyle 350/294 4/1940 Ott ..350/294 OTHER PUBLICATIONS Gunn, Method of Zone Melting, I.B.M. Technical Disclosure Bulletin, Vol. 10, No. 1, June 1967, p. 76.
Arrabito et al., Laser Perforation Technique IBM. Technical Disclosure Bulletin, Vol. 13, No. 10, March 1971, p. 3098.
Primary Examiner-Ronald L. Wibert Assistant Examiner-Michael J. Tokar [57] ABSTRACT A device for converging sunlight beams so to be able to ignite a fire or do solar cooking; the device consisting of a cylinder of frusto-conica, shape which is outwardly arcuate, the cylinder inner surface forming a reflector of the light beams so that when positioned with its axis parallel to the light beams, and with its wider mouth end toward the sun, the light rays reflected from the inner surface pass out the rear smaller mouth and the light rays converge together at a point rearward of the small mouth.
2 Claims, 5 Drawing Figures BEHIND MIRROR FOCUS LIGHT GATHERING DEVICE This invention relates generally to light focusing devices. More specifically it relates to devices for concentrating light rays.
A principal object of the present invention is to provide a light gathering device which can start a fire or do solar cooking by utilizing sun light rays.
Another object is to provide a light gathering device inwhich the sun rays are gathered to a commont point that is located rearwardly or behind the device, thus differing from reflectors where such point is forwardly thereof.
Another object is to provide a light gathering device which can be made in any of various sizes, and which for practical purpose can be small so that it is convenient to be carried in a pocket by a sportsman or scout out-of-doors.
Other objects are to provide a BEHIND MIRROR FOCUS LIGHT GATHERING DEVICE which is simple in design, inexpensive to manufacture, rugged in construction, easy to use, and efficient in operation.
These and other objects will be readily apparent upon a study of the following specification and the accompanying drawing wherein:
FIG. 1 is a perspective view of the invention shown in use.
FIG. 2 is a cross section on line 2-2 of FIG. 1.
FIG. 3 is a top view of the device.
FIG. 4 is a view similar to FIG. 2 and showing a modified design that includes a central cone for reflecting central light rays so to be more efficient by utilizing all the rays that otherwise would pass through the center opening without benefit.
FIG. 5 is a top view thereof.
Referring now to the drawing in detail, and more particularly to FIGS. 1 to 3 at this time, the reference numeral represents a behind mirror focus light gathering device according to the present invention, wherein there is a one piece shell 11 that consists only of a side wall around a central opening 12. The shell wall is of frusto-conical shape which is outwardly bulged or arcuate. The inner surface 13 thereof is mirror polished so to reflect light rays with maximum efficiency.
In operative use, the longitudinal axis of the device is made parallel to sun light rays 14 and the large mouth 15 of opening 12 is positioned toward the direction of the sun. Thus direct light rays 14 from the sun strike the surface 13 from which they reflect as reflected light rays 16 that pass outward of small mouth 17 of the opening 12, the reflected light rays 16 crossing each other at a point 18 that is rearwardly a distance away from the device 10. If the point 18 is located on a firewood 19 (as shown in FIG. 1), the concentrated light rays will be sufficient to ignite the same.
In FIGS. 4 and 5 a modified design of the device 20 is shown which includes the structure of above described device 10, and which additionally includes a concentric central conical shell 21 secured rigidly to shell 11 by means of three radial, thin fins 22 therebetween. The shell is positioned within the mouth 15 of shell 11 and has its conically pointed end 23 in a direction toward the sun. The side wall of the shell is outwardly bulged or arcuate, and the outer surface 24 thereof is mirror polished for maximum reflective efficiency. It is to be noted that the outer diameter of the base end 25 of the shell 21 is a same size as the mouth 17 so to utilize all the light rays entering the device without blocking any of the surface 13 from the direct sun rays.
In operative use, thus direct light rays 14 which otherwise would pass out. of the mouth 17 without useful work, are intercepted by the shell 21 so to cause such direct light rays 14 to reflect on surface 24 and reflect therefrom as reflected light rays 26 which strike on surface 13 and reflect therefrom as re-reflected light rays 27 which pass outward of mouth 17 and cross at the same point 18 where the reflected light rays 16 cross. Thus greater efficiency is obtained so that the device is equally operative when the sun is less bright.
It is to be noted that the shells 11 and 21 when viewed in a horizontal cross section, such as in FIG. 4 may have the arcuate bulges thereof either elliptical or circular about a constant point.
What is claimed is as follows:
1. A mirror device for focusing sun rays at a predetermined point comprising a larger shell having an inner concave reflecting arcuate surface, said shell having a circular inlet opening of larger diameter tapering to a concentric sun ray outlet opening of smaller diameter whereby the inner surface curves regularly in a longitudinal direction from the larger inlet opening to the smaller outlet opening forming a surface that reflects sun rays entering the inlet opening to a focal point outward of the outlet opening in combination with a smaller second shell having an arcuate convex outer surface which curves regularly from a point to an open circular end, said smaller shell being affixed concentrically within the larger shell by spaced radial fins wherein the point of the smaller shell projects towards the sun and beyond the inlet opeing of the larger shell, with the large end the smaller shell positioned between the inlet and outlet openings of the larger shell.
2. A device as in claim 1 wherein the large end of the smaller shell is midway between the inlet and outlet openings of the larger shell and whereby the outer diameter of the smaller shell at its large end is equal to the diameter of the outlet opening of the larger shell.

Claims (2)

1. A mirror device for focusing sun rays at a predetermined point comprising a larger shell having an inner concave reflecting arcuate surface, said shell having a circular inlet opening of larger diameter tapering to a concentric sun ray outlet opening of smaller diameter whereby the inner surface curves regularly in a longitudinal direction from the larger inlet opening to the smaller outlet opening forming a surface that reflects sun rays entering the inlet opening to a focal point outward of the outlet opening in combination with a smaller second shell having an arcuate convex outer surface which curves regularly from a point to an open circular end, said smaller shell being affixed concentrically within the larger shell by spaced radial fins wherein the point of the smaller shell projects towards the sun and beyond the inlet opeing of the larger shell, with the large end the smaller shell positioned between the inlet and outlet openings of the larger shell.
2. A device as in claim 1 wherein the large end of the smaller shell is midway between the inlet and outlet openings of the larger shell and whereby the outer diameter of the smaller shell at its large end is equal to the diameter of the outlet opening of the larger shell.
US00340096A 1973-03-12 1973-03-12 Behind mirror focus light gathering device Expired - Lifetime US3817605A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US00340096A US3817605A (en) 1973-03-12 1973-03-12 Behind mirror focus light gathering device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US00340096A US3817605A (en) 1973-03-12 1973-03-12 Behind mirror focus light gathering device

Publications (1)

Publication Number Publication Date
US3817605A true US3817605A (en) 1974-06-18

Family

ID=23331855

Family Applications (1)

Application Number Title Priority Date Filing Date
US00340096A Expired - Lifetime US3817605A (en) 1973-03-12 1973-03-12 Behind mirror focus light gathering device

Country Status (1)

Country Link
US (1) US3817605A (en)

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3899672A (en) * 1974-02-19 1975-08-12 Univ Chicago Solar energy collection
US3941973A (en) * 1974-06-26 1976-03-02 Raytheon Company Laser material removal apparatus
US3957031A (en) * 1975-05-29 1976-05-18 The United States Of America As Represented By The United States Energy Research And Development Administration Light collectors in cylindrical geometry
US4076014A (en) * 1976-08-12 1978-02-28 Wiquel Attilio William Solar cigarette lighter
FR2362408A1 (en) * 1976-08-16 1978-03-17 Us Energy DEVICE FOR CONCENTRATING AND COLLECTING RADIANT ENERGY
FR2407431A1 (en) * 1977-10-28 1979-05-25 Dubail Philippe Cigarette lighter using solar energy - is a compact, protected, truncated parabolic mirror with opening supporting cigarette
EP0018900A1 (en) * 1979-05-04 1980-11-12 Fernand Marcel Devienne High efficiency panel for emitting or collecting radiating energy, and process for the utilisation of such a panel
WO1982000719A1 (en) * 1980-08-13 1982-03-04 N Fourikis Energy collector
US4595833A (en) * 1983-09-20 1986-06-17 Sting Donald W Multiple internal reflection cell optical system for use in infrared spectrophotometry of liquid and fluidized samples
US4886348A (en) * 1988-10-26 1989-12-12 Westinghouse Electric Corp. Total transmissibility optical system
US4968126A (en) * 1990-02-20 1990-11-06 The United States Of America As Represented By The Secretary Of The Army All-optical device and method for remapping images
DE4122696A1 (en) * 1991-07-09 1993-01-21 Sick Optik Elektronik Erwin MIRROR COLLIMATOR
WO1998031971A1 (en) * 1997-01-18 1998-07-23 Tokenhouse Holdings Limited Solar energy collecting devices
US6613288B2 (en) 2001-01-22 2003-09-02 Candle Corporation Of America Device for releasing a volatile medium
US20060289001A1 (en) * 2005-06-24 2006-12-28 Byron Hopewell Solar stove
US20080212327A1 (en) * 2004-08-23 2008-09-04 Carl Zeiss Smt Ag Illumination System of a Microlithographic Exposure Apparatus
US20090084374A1 (en) * 2007-06-13 2009-04-02 Mills David R Solar energy receiver having optically inclined aperture
US20110073785A1 (en) * 2008-06-05 2011-03-31 Sagem Defense Securite Radiation Collector
US20210381724A1 (en) * 2020-06-08 2021-12-09 Nativus, Inc. Solar concentrator

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1085795A (en) * 1912-10-11 1914-02-03 Boylite Concentrator Inc Projection instrument.
US2198014A (en) * 1937-07-22 1940-04-23 Harry G Ott Optical system

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1085795A (en) * 1912-10-11 1914-02-03 Boylite Concentrator Inc Projection instrument.
US2198014A (en) * 1937-07-22 1940-04-23 Harry G Ott Optical system

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
Arrabito et al., Laser Perforation Technique I.B.M. Technical Disclosure Bulletin, Vol. 13, No. 10, March 1971, p. 3098. *
Gunn, Method of Zone Melting, I.B.M. Technical Disclosure Bulletin, Vol. 10, No. 1, June 1967, p. 76. *

Cited By (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3899672A (en) * 1974-02-19 1975-08-12 Univ Chicago Solar energy collection
US3941973A (en) * 1974-06-26 1976-03-02 Raytheon Company Laser material removal apparatus
US3957031A (en) * 1975-05-29 1976-05-18 The United States Of America As Represented By The United States Energy Research And Development Administration Light collectors in cylindrical geometry
US4076014A (en) * 1976-08-12 1978-02-28 Wiquel Attilio William Solar cigarette lighter
FR2362408A1 (en) * 1976-08-16 1978-03-17 Us Energy DEVICE FOR CONCENTRATING AND COLLECTING RADIANT ENERGY
FR2407431A1 (en) * 1977-10-28 1979-05-25 Dubail Philippe Cigarette lighter using solar energy - is a compact, protected, truncated parabolic mirror with opening supporting cigarette
EP0018900A1 (en) * 1979-05-04 1980-11-12 Fernand Marcel Devienne High efficiency panel for emitting or collecting radiating energy, and process for the utilisation of such a panel
FR2455714A1 (en) * 1979-05-04 1980-11-28 Devienne Fernand Marcel HIGH EFFICIENCY SENSOR OF RADIATED ENERGY
WO1982000719A1 (en) * 1980-08-13 1982-03-04 N Fourikis Energy collector
US4595833A (en) * 1983-09-20 1986-06-17 Sting Donald W Multiple internal reflection cell optical system for use in infrared spectrophotometry of liquid and fluidized samples
US4886348A (en) * 1988-10-26 1989-12-12 Westinghouse Electric Corp. Total transmissibility optical system
US4968126A (en) * 1990-02-20 1990-11-06 The United States Of America As Represented By The Secretary Of The Army All-optical device and method for remapping images
DE4122696A1 (en) * 1991-07-09 1993-01-21 Sick Optik Elektronik Erwin MIRROR COLLIMATOR
US5298736A (en) * 1991-07-09 1994-03-29 Erwin Sick Gmbh Mirror collimator having a large aperture ratio
WO1998031971A1 (en) * 1997-01-18 1998-07-23 Tokenhouse Holdings Limited Solar energy collecting devices
US6613288B2 (en) 2001-01-22 2003-09-02 Candle Corporation Of America Device for releasing a volatile medium
US20080212327A1 (en) * 2004-08-23 2008-09-04 Carl Zeiss Smt Ag Illumination System of a Microlithographic Exposure Apparatus
US8134687B2 (en) 2004-08-23 2012-03-13 Carl Zeiss Smt Gmbh Illumination system of a microlithographic exposure apparatus
US20060289001A1 (en) * 2005-06-24 2006-12-28 Byron Hopewell Solar stove
US20090084374A1 (en) * 2007-06-13 2009-04-02 Mills David R Solar energy receiver having optically inclined aperture
US20110073785A1 (en) * 2008-06-05 2011-03-31 Sagem Defense Securite Radiation Collector
US20210381724A1 (en) * 2020-06-08 2021-12-09 Nativus, Inc. Solar concentrator
US12061016B2 (en) * 2020-06-08 2024-08-13 Nativus, Inc. Solar concentrator

Similar Documents

Publication Publication Date Title
US3817605A (en) Behind mirror focus light gathering device
US3443086A (en) Beam-forming system
US4325612A (en) Reflective beam concentrator
US4770514A (en) Collimating compound catoptric immersion lens
US4557569A (en) Distended point source reflector having conical sections
JPS63190201A (en) Lighting apparatus for bicycle
JPH02504319A (en) collimator
US2823612A (en) Target seeker head for guided missiles
US4050775A (en) Catoptric lens arrangement
US4754381A (en) Ellipsoidal reflector concentration of energy system
US3892476A (en) Catoptric system for simultaneous concentration of light, laser, and other type paraxial rays into beams
US4221459A (en) Erect image telescope optical system
SE8803897L (en) A solar collection
US2064252A (en) Incandescent lamp and projection device
US4031384A (en) Catoptric system for simultaneous concentration of light, laser, and other type paraxial rays into beams
GB763376A (en) Improvements relating to vehicle lamps
US4657353A (en) Conical beam concentrator
US4657721A (en) Target illumination
GB2040490A (en) Prism for Use With a Light Guide
US3624834A (en) Optical concentrator without flux loss
GB1440016A (en) Projection screens
SU1543370A1 (en) Mirror concentrator
US4183612A (en) Optical system for creating high-intensity solar light beam
US4572621A (en) Conical beam concentrator
SU167327A1 (en) FOCON