US3009054A - Prismatic lighting fixture - Google Patents

Prismatic lighting fixture Download PDF

Info

Publication number
US3009054A
US3009054A US667108A US66710857A US3009054A US 3009054 A US3009054 A US 3009054A US 667108 A US667108 A US 667108A US 66710857 A US66710857 A US 66710857A US 3009054 A US3009054 A US 3009054A
Authority
US
United States
Prior art keywords
light
lens
fixture
reflectors
lamp
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
US667108A
Other languages
English (en)
Inventor
William E Thomas
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.)
PRISM SIGNS Inc
Original Assignee
PRISM SIGNS 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 PRISM SIGNS Inc filed Critical PRISM SIGNS Inc
Priority to US667108A priority Critical patent/US3009054A/en
Application granted granted Critical
Publication of US3009054A publication Critical patent/US3009054A/en
Priority to BE646627A priority patent/BE646627A/xx
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F21—LIGHTING
    • F21V—FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR
    • F21V13/00—Producing particular characteristics or distribution of the light emitted by means of a combination of elements specified in two or more of main groups F21V1/00 - F21V11/00
    • F21V13/02—Combinations of only two kinds of elements
    • F21V13/04—Combinations of only two kinds of elements the elements being reflectors and refractors
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F21—LIGHTING
    • F21S—NON-PORTABLE LIGHTING DEVICES; SYSTEMS THEREOF; VEHICLE LIGHTING DEVICES SPECIALLY ADAPTED FOR VEHICLE EXTERIORS
    • F21S8/00—Lighting devices intended for fixed installation
    • F21S8/04—Lighting devices intended for fixed installation intended only for mounting on a ceiling or the like overhead structures
    • F21S8/06—Lighting devices intended for fixed installation intended only for mounting on a ceiling or the like overhead structures by suspension
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F21—LIGHTING
    • F21V—FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR
    • F21V7/00—Reflectors for light sources
    • F21V7/0008—Reflectors for light sources providing for indirect lighting
    • F21V7/0016—Reflectors for light sources providing for indirect lighting on lighting devices that also provide for direct lighting, e.g. by means of independent light sources, by splitting of the light beam, by switching between both lighting modes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F21—LIGHTING
    • F21V—FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR
    • F21V7/00—Reflectors for light sources
    • F21V7/005—Reflectors for light sources with an elongated shape to cooperate with linear light sources
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F21—LIGHTING
    • F21Y—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES F21K, F21L, F21S and F21V, RELATING TO THE FORM OR THE KIND OF THE LIGHT SOURCES OR OF THE COLOUR OF THE LIGHT EMITTED
    • F21Y2103/00—Elongate light sources, e.g. fluorescent tubes

Definitions

  • This invention relates generally to light fixtures of the type suitable for general illuminating purposes, and which employ a line type of light source, such as rectilinear fluorescent orfilament lamps.
  • Diffusing means may be used with such fixtures, as for example, a screen of translucent material extending in front of the light sources, or diffusing reflectors.
  • a screen of translucent material extending in front of the light sources, or diffusing reflectors.
  • Another object of the invention is to provide a fixture of the above character having low surface brightness, with resulting case on the eyes of an observer looking directly at the same.
  • Another object of the invention is to provide a light fixture of the above character having an optimum light distribution pattern. More particularly the light is controlled in such a manner that substantially all of the light output from the source is directed downwardly within a limited angle, thus resulting in bright illumination directly below the fixture and providing a minimum amount of light beyond the desired distribution pattern.
  • Another object of the invention is to provide a fixture of the above character having relatively small housing depth, thereby providing an attractive appearance and facilitating installation.
  • Another object of the invention is to provide a fixture of the above character which'provides relatively uniform distribution of light over a desired area.
  • FIGURE 1 is a side elevational view illustrating a light fixture incorporating the present invention.
  • FIGURE 2 is a cross-sectional detail on an enlarged scale, taken along the line 2-2 of FIGURE 1.
  • FIGURE 3 is a view like FIGURE 2 but showing the lamp images.
  • FIGURE 4 is an enlarged cross-sectional detail illustrating the contouring for the lens segments.
  • FIGURES 5 and 6 are light distribution patterns for one particular example.
  • the particular fixture illustrated in FIGURES 1 and 2 is intended for overhead installation. It consists of a relatively flat housing 10 adapted to be supported from a ceiling either by directly attaching the housing, or by means of suspension members 11.
  • the front side of the housing is covered by the lens 12, which is formed of a suitable light transmitting material, such as a transparent or translucent plastic.
  • the lens 12 which is formed of a suitable light transmitting material, such as a transparent or translucent plastic.
  • a light source in the form of a fluorescent tube 13, which is carried at its ends by conventional sockets 14. Note that the tube is located coincident with the vertical center plane of the fixture.
  • a conventional transformer or ballast device is indicated at 15.
  • the curved reflectors 16 which extend the length of the fixture, and which are on opposite sides of the vertical center plane.
  • I provide the flat inclined reflectors 17.
  • I provide the curved reflectors 18 which likewise extend the length of the fixture, and which also are disposed on opposite sides of the vertical center plane.
  • light from the sides of the tube 13 may, for example, travel along paths 21 and 22 to the flat reflectors 17, and then be reflected downwardly to the lens 12, along the lines 23 and 24.
  • Curved reflectors 16 receive the light from the upper side of the tube 13, and reflect such light toward the lens 12.
  • Curved reflectors 18 reflect light from the lower side of the tube, and direct it upwardly and outwardly to the curved reflectors 16 and fiat reflectors 17.
  • the lens 12 is of the Fresnel type and is formed in two sections 12a and 12b, which adjoin along a line coincident with the center vertical plane of the fixture. Each section extends for the length of the fixture.
  • FIG- URE 4 illustrates one lens section, namely the section 12a. Note that it consists of a plurality of lens elements extending the length of the fixture, and which are designed to collect light from the reflector system, and direct it downwardly in a predetermined distribution pattern.
  • the representative marginal lens elements for section 12a are designated as 1a, a representative element which is about midway between the margins as 3a, and representative elements intermediate 1a and 3a, as 2a.
  • each element 2a has an upper curved surface 28 and a lower planar surface 29.
  • the curvature of surface 28 is distorted from cylindrical as illustrated, whereby the convexity is progressively greater toward that edge of the element nearest the element 3a.
  • the plane of surface 29 is tilted at an acute angle with respect to the plane of the lens.
  • the upper surface 31 is likewise distorted as for the element 2a, but the distortion is somewhat greater.
  • the lower surface 32 is also tilted with respect to the plane of the lens, and the angle of tilting is greater. As is evident from FIGURES 2 and 3, the distortion of the upper curved surfaces of all the lens elements for each section becomes progressively greater toward th side edges of the same. Likewise the lower surfaces of the elements are tilted at progressively increasing angles.
  • the fiat reflectors 17 are so positioned whereby the optical effect is to provide two virtual lamp light images 13a and 13b, which fall outside of the housing. Also the arrangement is such that these images are disposed immediately above the centers of the two lens sections 12a and 12b, and are spaced from the lens a distance substantially twice the actual spacing between lamp 13 and the lens. All light rays from one of the images 13a and 13b are essentially downwardly and are directed upon the respective lens sections 12a and 12b. Since the cosine of angle 36 is so nearly unity, there is no discernible difference between the intensity of the light falling upon different portions of each lens section, from each of the virtual images. In other words, as viewed from the exterior, the lens is of substantially the same brightness over its entire area.
  • the curved reflectors 16 receive light coming from the upper side of the lamp 13, and direct it downwardly upon the lens. Therefore these reflectors conserve light from the lamp which would otherwise not strike the flat reflectors 17. Similarly the reflectors 18 receive light from the lower side of the lamp, and reflect such light to the flat reflectors 17 The reflectors 18 are so dimensioned that they do not interfere with proper uniform illumination of the lens sections.
  • the images of the reflectors 16 are indicated at 16a and 16b, and similarly the images of reflectors 13 are indicated at 18a and 18b.
  • FIGURE 4 The paths of light through three representative elements of one lens section are shown in FIGURE 4.
  • the middle ray 41 is reflected straight downwardly, or at right angles to the plane of the lens 12, while the ray 42 is refracted at a slightly greater angle, and the rays 43 at a slightly lesser angle than the center ray 41.
  • emerging rays corresponding to the rays 42 and 43 are at a small angle 44 with respect to the vertical.
  • the angles 44 are equal by virtue of the distorted curvature of the surface 31.
  • This shaping is dependent upon the index of refraction of the transparent material used for the lens sheet, and the spread of light desired from the lens.
  • Light rays are refracted by lens elements 2a in substantially tthe same manner as previously described. The same applied to lens elements corresponding to element 3a, which have a cylindrical upper surface 26.
  • FIGURES 5 and 6 illustrate typical light patterns which have been obtained by use of my fixture.
  • FIG- URE 5 is a distribution pattern and taken in a vertical plane crosswise of the fixture.
  • FIGURE 6 is a distribution pattern taken in a vertical plane extending through the longitudinal center of the fixture.
  • Curve 46 represents regions of equal illumination from the fixture, and corresponds generally to the boundaries of the illuminated space. Note that the illumination is sharply confined and concentrated in the space below the fixture. Assuming the illumination of a work area below the fixture, such illumination is relatively uniform within the boundaries of the distribution pattern, and if an observer looks directly at the lens, no bright spots will be noted.
  • FIGURE 6 The distribution pattern shown in FIGURE 6 was plotted in a similar manner and likewise shows the way in which the light from the fixture is confined and concentrated in the space below the same.
  • the spread of light from the ends of the fixture is somewhat greater than from the sides, because the lens elements extend longitudinally.
  • the fixture which attains all of the objects previously stated. Particularly, it provides relatively high lighting efiiciency in that a high percentage of the light from the lamp is effectively utilized. Because of the manner in which the light is concentrated downwardly from the lens, an ordinary observer of the fixture will notice very little light coming from the lens, unless he is within the light distribution pattern. In general the fixture as a relatively large illuminating area, but at the same time it is relatively compact with respect to its vertical dimensioning. In other words, the invention makes possible a housing 10, which is relatively fiat, and which therefore has an attractive appearance, and can be readily installed on a ceiling. A further feature of the invention is that it permits the use of a single light tube or a lamp, while at the same time providing illumination from a relatively large area.
  • Fixtures in accordance with the present invention can be utilized separately where concentrated lighting is desired, or may be used in multiples, mounted side by side or in any arrangement desired, to illuminate a larger area.
  • a single rectilinear lamp characterized by relative shallowness and reduced surface brightness, a single rectilinear lamp, a housing, said housing enclosing the lamp and having an open side, a planar lens of light transmitting material carried by the housing and extending across said open side, said lens being formed in two duplicate sections joined along the longitudinal center plane of the fixture and having a plurality of longitudinally extending lens elements parallel to said rectilinear lamp, a first pair of reflectors supported by the housing and including flat portions disposed at equal angles on opposite sides of the lamp and extending longitudinally of the fixture, said reflectors also including curved portions extending inwardly to a position on said central plane adjacent a side of the lamp remote from the lens, a second pair of reflectors interposed between the lamp and the lens and having curved portions extending outwardly from a position on said central plane, said last named reflectors directing light at said first pair of reflectors to form two separate spaced apart images capable of indirectly lighting each of said two duplicate lens sections, said

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Non-Portable Lighting Devices Or Systems Thereof (AREA)
US667108A 1957-06-21 1957-06-21 Prismatic lighting fixture Expired - Lifetime US3009054A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
US667108A US3009054A (en) 1957-06-21 1957-06-21 Prismatic lighting fixture
BE646627A BE646627A (en)) 1957-06-21 1964-04-16

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US667108A US3009054A (en) 1957-06-21 1957-06-21 Prismatic lighting fixture

Publications (1)

Publication Number Publication Date
US3009054A true US3009054A (en) 1961-11-14

Family

ID=24676820

Family Applications (1)

Application Number Title Priority Date Filing Date
US667108A Expired - Lifetime US3009054A (en) 1957-06-21 1957-06-21 Prismatic lighting fixture

Country Status (2)

Country Link
US (1) US3009054A (en))
BE (1) BE646627A (en))

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3065333A (en) * 1961-03-13 1962-11-20 Spaulding Fluorescent lighting fixture
US3130924A (en) * 1961-09-27 1964-04-28 John W Gish Non-glare lamp
US4053762A (en) * 1975-12-29 1977-10-11 Armstrong Cork Company Twin-beam luminaire lens
US4059755A (en) * 1975-12-29 1977-11-22 Armstrong Cork Company Luminaire lens insert
US4078169A (en) * 1976-08-23 1978-03-07 Armstrong J Delvin Apparatus for promoting plant growth with artificial light
US4115843A (en) * 1977-05-04 1978-09-19 Dominion Auto Accessories Limited Warning lamp
US4488208A (en) * 1982-08-20 1984-12-11 Union-Reed Corporation Low brightness lens for circular fluorescent lamps
US20050281023A1 (en) * 2004-06-18 2005-12-22 Gould Carl T Light fixture and lens assembly for same
EP1628070A2 (de) 2004-08-18 2006-02-22 Aldi Einkauf GmbH & Co. oHG Beleuchtungseinrichtung
USD612534S1 (en) 2008-04-24 2010-03-23 Abl Ip Holding Llc Bracket
EP2196725A1 (de) * 2008-12-09 2010-06-16 Manfred Grimm Leuchte
US20100284174A1 (en) * 2009-05-06 2010-11-11 Foxsemicon Integrated Technology, Inc. Illumination device with anti-glare plate
USD640825S1 (en) 2008-04-24 2011-06-28 Abl Ip Holding Llc Louver
US8153894B2 (en) 2008-04-01 2012-04-10 Abl Ip Holding Llc Mounting system
US8220957B2 (en) 2007-02-12 2012-07-17 Abl Ip Holding Llc Retrofit light assembly
EP2884158A1 (en) * 2013-12-12 2015-06-17 Toshiba Lighting & Technology Corporation Luminaire
USD806930S1 (en) * 2016-01-27 2018-01-02 Fluxwerx Illumination Inc. Suspended luminaire
USD815333S1 (en) * 2017-08-30 2018-04-10 Fluxwerx Illumination Inc. Suspended luminaire

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4748547A (en) * 1987-02-06 1988-05-31 Baker Glenn A Uplight luminaire for achieving uniform illuminance across a ceiling

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1900551A (en) * 1931-02-28 1933-03-07 Edwin F Guth Lighting unit for reflected illumination
US1923653A (en) * 1932-02-08 1933-08-22 James E Brailey Headlight
US2125635A (en) * 1935-01-14 1938-08-02 John P Hobart Illuminating device
US2318716A (en) * 1941-07-05 1943-05-11 Holophane Co Inc Luminaire
US2368014A (en) * 1943-02-10 1945-01-23 Holophane Co Inc Luminaire

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1900551A (en) * 1931-02-28 1933-03-07 Edwin F Guth Lighting unit for reflected illumination
US1923653A (en) * 1932-02-08 1933-08-22 James E Brailey Headlight
US2125635A (en) * 1935-01-14 1938-08-02 John P Hobart Illuminating device
US2318716A (en) * 1941-07-05 1943-05-11 Holophane Co Inc Luminaire
US2368014A (en) * 1943-02-10 1945-01-23 Holophane Co Inc Luminaire

Cited By (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3065333A (en) * 1961-03-13 1962-11-20 Spaulding Fluorescent lighting fixture
US3130924A (en) * 1961-09-27 1964-04-28 John W Gish Non-glare lamp
US4053762A (en) * 1975-12-29 1977-10-11 Armstrong Cork Company Twin-beam luminaire lens
US4059755A (en) * 1975-12-29 1977-11-22 Armstrong Cork Company Luminaire lens insert
US4078169A (en) * 1976-08-23 1978-03-07 Armstrong J Delvin Apparatus for promoting plant growth with artificial light
US4115843A (en) * 1977-05-04 1978-09-19 Dominion Auto Accessories Limited Warning lamp
US4488208A (en) * 1982-08-20 1984-12-11 Union-Reed Corporation Low brightness lens for circular fluorescent lamps
CN101614364B (zh) * 2004-06-18 2012-06-27 艾柯蒂布兰兹公司 用于电灯器具的透镜组件
US20050281023A1 (en) * 2004-06-18 2005-12-22 Gould Carl T Light fixture and lens assembly for same
US7261435B2 (en) * 2004-06-18 2007-08-28 Acuity Brands, Inc. Light fixture and lens assembly for same
CN1710323B (zh) * 2004-06-18 2012-07-04 艾柯蒂布兰兹公司 电灯器具和用于电灯器具的透镜组件
EP1628070A3 (de) * 2004-08-18 2006-09-20 Aldi Einkauf GmbH & Co. oHG Beleuchtungseinrichtung
EP1628070A2 (de) 2004-08-18 2006-02-22 Aldi Einkauf GmbH & Co. oHG Beleuchtungseinrichtung
AU2005203135B2 (en) * 2004-08-18 2010-04-08 Aldi Einkauf Gmbh & Co. Ohg Illumination device
US8220957B2 (en) 2007-02-12 2012-07-17 Abl Ip Holding Llc Retrofit light assembly
US8153894B2 (en) 2008-04-01 2012-04-10 Abl Ip Holding Llc Mounting system
USD640825S1 (en) 2008-04-24 2011-06-28 Abl Ip Holding Llc Louver
USD612534S1 (en) 2008-04-24 2010-03-23 Abl Ip Holding Llc Bracket
EP2196725A1 (de) * 2008-12-09 2010-06-16 Manfred Grimm Leuchte
US8162513B2 (en) * 2009-05-06 2012-04-24 Foxsemicon Integrated Technology, Inc. Illumination device with anti-glare plate
US20100284174A1 (en) * 2009-05-06 2010-11-11 Foxsemicon Integrated Technology, Inc. Illumination device with anti-glare plate
EP2884158A1 (en) * 2013-12-12 2015-06-17 Toshiba Lighting & Technology Corporation Luminaire
USD806930S1 (en) * 2016-01-27 2018-01-02 Fluxwerx Illumination Inc. Suspended luminaire
USD815332S1 (en) * 2016-01-27 2018-04-10 Fluxwerx Illumination Inc. Suspended luminaire
USD818627S1 (en) * 2016-01-27 2018-05-22 Fluxwerx Illumination Inc. Suspended luminaire
USD815333S1 (en) * 2017-08-30 2018-04-10 Fluxwerx Illumination Inc. Suspended luminaire

Also Published As

Publication number Publication date
BE646627A (en)) 1964-10-16

Similar Documents

Publication Publication Date Title
US3009054A (en) Prismatic lighting fixture
US3647148A (en) Veiling glare control with luminaires
US4336576A (en) Lighting apparatus
US4698734A (en) Lensed indirect luminaire with side angle brightness control
US3735124A (en) Prismatic lenses for lighting fixtures
US4729075A (en) Constant zone reflector for luminaires and method
US4242723A (en) Low level work area lighting system
NO168387C (no) Indirekte speilende lysarmatur
US4954935A (en) Lighting system for illuminating billboards and the like
US4451875A (en) Poster panel lighting fixture
US2526074A (en) Lighting fixture having means to shield the light source
US2143148A (en) Light shield
US3786248A (en) Luminaire
US6170962B1 (en) Dual compound reflector for fluorescent light fixtures
US3296431A (en) Illuminated display fixture
US1740229A (en) Lighting apparatus
US2305722A (en) Lighting fixture
US3654451A (en) Floodlight
ATE112030T1 (de) Verbesserungen an befestigungen für beleuchtungsröhren.
US3480772A (en) Luminaire
US1480904A (en) Highway illuminator
US4833575A (en) Brightness equalizing light filter system
GB1408955A (en) Illumination apparatus
US6164798A (en) Asymmetrical compound reflectors for fluorescent light fixtures
US3239659A (en) Glare-reducing lamp