US3794829A - Non-luminance lighting panel - Google Patents

Non-luminance lighting panel Download PDF

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Publication number
US3794829A
US3794829A US00245904A US3794829DA US3794829A US 3794829 A US3794829 A US 3794829A US 00245904 A US00245904 A US 00245904A US 3794829D A US3794829D A US 3794829DA US 3794829 A US3794829 A US 3794829A
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panel
elements
pointed
axis
symmetry
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US00245904A
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I Taltavull
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    • 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
    • F21V5/00—Refractors for light sources
    • F21V5/02—Refractors for light sources of prismatic shape

Definitions

  • ABSTRACT A transparent prismatic low luminescent lighting panel of a type having a plurality of refracting prismatic elements on its outer surface in the form of pyramids or cones, said elements having curved surfaces, wherein said elements in conical form have cross-sectional profiles and are situated on the surface of the exterior face of said panel such that luminous rays which by reason of their angle of incidence relative to the panel, suffer little energy loss on travelling through the thickness of the panel and which because of incidence at certain points of the panel, emerge from said conical elements defining angles of between 60 and 90 with respect to the axis of symmetry of said conical elements strike an adjacent cone and suffer total internal reflection, thus reducing the low luminance of said panel.
  • Said refracting elements of pyramidal form are situated on the exterior face of the panel forming therebetween narrow, flat zones whiclmprove the light efficiency of said panel without having an unfa vorable effect on the luminescence of said panel.
  • the invention refers to lighting panels for use in lighting units having fluorescent tubes as a lighting source, and more particularly refers to low luminescent lighting panels of the type described in my above mentioned patent which consists of an outer surface having a multiplicity of refracting prismatic elements in the form of cones or pyramids, the lateral surfaces of which are constructed such that luminous rays emerging from said cones or pyramids form angles of less than 60 with the axis of symmetry of said cones so'as to obtain a lighting panel of theoretically nil luminance.
  • the laterally curved surface of the pyramids in an axial plane normal to two opposing laterally curved surfaces is bounded by two curved lines which are symmetric with respect to the axis of symmetry of the pyramid, each of which is made up an are which has its center situated on opposite sides of said axis of symmetry, and above the plane of the base of the pyramid.
  • the cross section of the cones through an axial plane are defined by two lines symmetric with respect to the axis of symmetry of the cones, each one of which constitutes a first arc, the center of which is situated on the opposite side of said axis of symmetry and above the plane of the base of the cone, a straight line segment tangential to said first arc, and a second arc tengential to said straight line segment, the center of which is situated at the other side of said axis of symmetry of the cone and in the plane of the base of said cone.
  • the special structure of the refracting cones causes all the rays which emerge from the cones to form angles of not more than 60 with respect to the axis of symmetry of the cones, the remaining rays undergo total internal reflection and are reflected towards the interior face of the panel, thus being eliminated and giving a panel of theoretically nil luminance.
  • some luminous rays with points of incidence at certain points on the interior surface of the panel may emerge from the exterior face of the panel forming angles of greater than t 5 with respect to the axis of symmetry of the cones.
  • the principal object of the invention is to provide an improved lighting panel of low luminance, having on its exterior surface a plurality of prismatic refracting elements in the form of cones having a curved lateral surface and rounded apex in which the luminance, caused by rays striking the panel at points on the interior face in a normal or substantially normal direction to said interior surface of the panel is eliminated.
  • Another object of the invention is to provide lighting panel of low luminance, having on its outer face refracting prismatic elements in the form of cones but having rounded apexes and including zones which do not influence the luminance of the panel and which increase the light efficiency of the panel.
  • a further object of the invention is to provide a panel of low luminance having on its exterior surface refracting prismatic elements in the form of pyramids having curved lateral faces and with an improved light output ratio.
  • Another object of the invention is to provide a lighting panel of low luminance having on its exterior surface refracting prismatic elements in the form of pyramids having curved lateral faces whereby the panel has improved mechanical rigidity.
  • the invention comprises constructing the refracting cones of the panel such that the cones have circular bases and a peripheral surface defined by a line composed of a first arc and a second are having the centers situated on opposite sides of the axis of symmetry of the cone and above the plane of the base of said first and second arcs and a third are tangential to said straight line segments and having its center situated at the intersection of the axis of symmetry of the cone with the plane of the base of said cone.
  • the invention also comprises the positioning of the cones on the panel with the bases of each two adjacent cones superimposed on each other in such a way that the lateral surfaces of the cones intersect, thus reducing or eliminating flat portions of the panel between cones, reducing the luminance of the panel.
  • Another achievement of the invention refers to a panel with refracting prismatic elements in the form of pyramids having curved lateral surfaces as described in my patent and includes making these pyramids with squared bases and positioning them with their bases spaced in such a way that greater rigidity of the panel is achieved without an increase in weight, and at the same time increasing the light efficiency of the panel without unfavorably affecting the low luminance of the panel.
  • FIG. 1 is a view in plan from below of a portion of a panel having refracting cones in staggered positions and tangential to one another and with some similar small cones between said cones. 7
  • FIG. 2 is a schematic cross-sectional view through the line IIII of FIG. 1 showing the path of the rays through the panel.
  • FIG. 3 is a view in plan from below of a panel having refracting cones in staggered positions and partially intersecting one another, two by two, the bases of the cones cut in hexaganal forms.
  • FIG. 4 is a schematic cross-sectional view through the line IV-IV of FIG. 3 showing the path of the luminous rays through the panel.
  • FIG. 5 is a view in plan from below of a portion of a panel having refracting cones positioned in rows along orthogonal lines and partially overlapping, two by two, the bases of said cones being cut in square form and having bevelled vertices and including similar small cones between the larger cones.
  • FIG. 6 is a schematic cross-sectional view through the line Vl-VI of FIG. 5 showing the path of the luminous rays through the panel.
  • FIG. 7 is a view in plan from below of a portion of a panel having refracting cones arranged in orthogonal rows and columns and partially overlapping one another and the bases of said cones being cut in square form.
  • FIG. 8 is a schematic cross-sectional view through the line VIIIVIII of FIG. 7 showing the path of luminous rays through the panel.
  • FIG. 9 is a view in plan from below of a portion of a panel having refracting pyramids of curved lateral surfaces and having square bases, arranged in orthogonal rows and columns and having their bases evenly spaced.
  • FIG. 10 is a schematic cross-sectional view through the line XX of FIG. 9 showing the path of the luminous rays through the panel.
  • the primary purpose of this invention is to improve the lighting panel described in my US. Pat. No. 3,716,709 which refers to the profile of the axial section of the refracting cones and to the arrangement on the surface of the panel of said cones and of the refracting pyramids of curved lateral surfaces which consititute refracting prismatic elements of the panel of said patent.
  • the present invention comprises, in the case in which said prismatic refracting elements of the lighting panel are the aforementioned cones, constructing the cones according to the following description and positioning them appropriately.
  • the surfaces of the cones are defined by two arcs which are, symmetric to the axis of symmetry of the cone and which have centers at the points 2 and 3 respectively situated on either side of said axis of symmetry on a line parallel to the plane of the base of said cone.
  • Two line segments are situated above said plane, symmetric with respect to the axis of symmetry of the cone and tangential respectively to said two symmetric arcs.
  • a third are is tangential to the two symmetric line segments and has its center at point 4 which is at the intersection of the plane of the base of the cone and the axis of symmetry thereof.
  • the cones constructed according to the form described can be arranged on the surface of the panel in the manner shown in FIG. 1 which corresponds with the arrangement FIG. 5 in my US. Pat. No. 3,716,709 according to which the cones are in staggered relation with their bases 9, ll, 13, tangential to each other, in pair-wise relationship and including some cones similar to those mentioned but of smaller dimension situated in the flat spaces 28 between the bases of three contiguous cones and with their respective bases 8, 10, 12 tangential to the bases of said larger cones.
  • the distance between the axis E and I, of two consecutive cones of bases 9 and 13 is equal to 2 E G ZG F tan 3.464 G F G F being the radius of the base of the cone.
  • FIG. 2 which is a cross section of the panel through the line II-ll of FIG. 1 which coincides with the line l-l' defined by the centers of the bases of the cones 9 and 13, we observe that the profile 23 of the surface of the cone 9 is constituted by a curved line comprising two arcs which are symmetric with respect to the axis E of the cone and have centers at the points 2 and 3 which are situated at either side of the axis E on a straight line parallel to said line 1-l' and above the plane of the interior face of the panel represented by the straight line ST the arcs extending from the plane of the exterior face of the panel to a line which preferable forms an angle of 45 with said straight line 2-3; an arc with its center at point 4 situated at the intersection of the axis E, of the cone and the plane of the exterior face of the panel and which extends preferably 45 beyond the axis E and two line segments symmetric with respect to said axis E and tangential to the are having center 4 and to the respective arcs having
  • the profile 24 of the axial section of the cone of base 13 and of axis I is formed in the same manner as are the profiles of the remaining cones of the panel.
  • FIG. 2 axial cross sections of the intermediate cones of small dimension of bases 10 and 12 the profiles of which, 25 and 26 are similar to the profiles 23 and 24 of the cones of bases 9 and 13 already described may be observed and it is seen that between these sections of cones 25 and 26 there is a flat portion indicated by the number 30.
  • the refracting cones are staggered and partially intersect in such a way that the bases of said cones are cut in the form of regular hexagons, without having any flat surface between adjacent cones and the profiles 23, 24 of the axial sections of said cones are equal to that previously described in relation to the embodiment of FIGS. 1 and 2.
  • the radius of the base of said cones F H and the respective centers of the bases are situated on the straight line l4l4' the distance E 1 between the axis of symmetry of two consecutive nonadjacent cones of sections 23, 24, is determined by that is, it is equal to three times the radius of the circumference of the base of the cones.
  • FIG. 4 discloses that the path of the luminous rays corresponding to points 17 and 18 are analogous to those obtained by the embodiment of FIG. 2, while the luminous rays having points of incidence at G included between the bases of the cones 23 and 24 where the axial cross section presents the profile of the curve 27 corresponding to the line of intersection of the lateral surfaces of two adjacent cones, are refracted thus forming angles not greater than 39 with the between the base axis of symmetry E I which shows that luminence is not produced in this zone and that on the other hand an increase in the light output ratio from the panel as a whole is obtained.
  • the refracting cones are arranged in orthogonal rows and columns and have their lateral surfaces intersecting adjacent cones but leaving a small space between each set of four adjacent cones, in such a way that the bases of the said cones are cut in a square form having bevelled vertices, with small cones similar to those of 8, 10, 12, of FIG. 1 occupying those intermediate regions, with their bases tangential to the bases of said four adjacent cones, and in which the profile 25 ofa surface is similar to the profiles 23, 24 of the surfaces of the larger refracting cones.
  • the distance 5 between the axis of two consecutive cones, the centers of the bases of which are situated on the straight line -15 as are the centers of the bases of the corresponding small intermediate cones, is equal to 2 E l the diameter of the small intermediate cone; that is, about 2.31 times the value of the radius of the base of the cone.
  • the refracting cones are also arranged in orthogonal rows and columns with their adjacent lateral surfaces intersecting in such a way that their bases are in the form of squares which are contiguous to each other. That is they are arranged in an analogous form to that of FIG. 5 but without any intermediate spaces between the cones, and consequently there are no small dimension cones.
  • a low luminance lighting panel having on its exterior surface a plurality of refracting prismatic elements consisting of pyramids each having a square base and having curved lateral surfaces, which more specifically are cylindrical surfaces. Its cross-section through an axial plane normal to two lateral opposite faces, represented by the line A B or by the line C D of FIG. 9, is bounded by two arcs F P and F P the centers of which are situated at points E and E respectively, which are symmetric with respect to the axis of symmetry of the pyramid and which are on a straight line parallel to the interior face of the panel and above it, similar to that described in my US. Pat. No. 3,716,709 with relation to FIG. 2 of the same.
  • a portion of the luminous rays, j k L s t emenating from point N of the interior surface of the panel situated in front of one of the flat zones G H is refracted in a concentrated form according to the directions m 40 n 0, p and q which correspond exactly to those rays incident on the interior surface of the panel in a substantially normal direction to said surface, while the remaining rays undergo total internal reflection and are eliminated in the directions j k r s and r with the result that the flat spaces G H,
  • G 'H considerably increases the light output ratio of the panel, without having an unfavorable influence on the low luminance of the panel.
  • a low-luminance lighting panel comprising a plurality of refracting prismatic elements of pointed dome shape situated on the outer surface of said panel, each of said elements having a circular base and an axis of symmetry wherein the lateral surfaces of said elements are defined by lines symmetric to said axis of symmetry of the pointed element, each of said lines being comprised of a first are having a center situated beyond the axis of symmetry of said pointed element and above the plane of the inner face of the panel, a line segment tangential to said first arc, and a second arc tangential to said line segment and having its center situated at the intersection of the axis of the symmetry of the element and the plane of the base of the element.
  • a lighting panel of low luminance comprising a plurality of main optical refracting elements of pointed dome shape situated on the outer surface of said panel,
  • each of said elements having a circular base and an axis of symmetry and having curved lateral surfaces with respect to the axis of symmetry of the pointed element, the cross-section of each of said main pointed elements taken through an axial plane being defined by a curved line comprising first and second arcs symmetric with respect to said axis of symmetry of the pointed element, each of said arcs having a center at a point situated beyond said axis of symmetry equidistant from said axis of symmetry and on a straight line parallel to the plane of the interior face of the panel, a third arc having its center situated at the intersection of the axis of symmetry of the pointed element with the base of said pointed element and covering equal angles on each side of said axis of symmetry of the pointed element, and two line segments symmetric with relation to said axis of symmetry of the pointed element and tangential respectively to said third are and to said first and second arcs of said elements defining flat regions between adjacent elements; and a plurality of optical refrac
  • a lighting panel according to claim 2 wherein said main pointed elements are arranged in staggered relation on the outer face of the panel, having their bases tangential to others thereof and each of said smaller pointed elements having its base tangential to the bases of three surrounding main pointed elements.
  • a lighting panel according to claim 2 wherein said main pointed elements are arranged on the exterior face of the panel in orthogonal rows and columns having their lateral surfaces intersecting others thereof such that the bases of said main pointed elements are in squared form having bevelled vertices according to an arc of the base of the pointed element, and each one of said similar but smaller pointed elements positioned between four main continguous pointed elements with its base tangential to the bases of the said four main pointed elements.
  • a low luminance lighting panel having on its exterior surface a plurality of optical refracting elements of pointed dome shape having a circular base and an axis of symmetry wherein the axial cross sections of said pointed elements are defined by symmetric lines to said axis of symmetry of the pointed element each of said lines being composed ofa first are having its center situated beyond the axis of symmetry of the pointed element and above the plane of the inner face of the panel, a straight line segment tangential to said first and second arc, tangential to said straight line segment and having its center situated at the intersection of the axis of symmetry of the pointed element and the base of said pointed element, each of said refracting optical pointed elements partially intersecting other elements laterally.
  • a lighting panel according to claim 5 wherein said refracting optical pointed elements are positioned in staggered relation on the outside face of the panel, in such a way that a common chord of the bases of each two intersecting pointed elements cover arcs of 60 of the circumferences of the bases, which have the form of regular hexagons.
  • a lighting panel according to claim 5 wherein the intersecting optical refracting pointed elements are arranged on the exterior face of the panel in orthogonal rows and columns.
  • a lighting panel according to claim 7 wherein the intersecting optical refracting pointed elements are arranged such that the common chord of the bases of each two intersecting pointed elements define arcs of less than 90 of the circumference of said bases, said bases thus having a squared form having bevelled vertices with small arcs and thus providing a flat space between each four continguous intersecting pointed elements, each flat space being occupied by a pointed element of smaller dimension, the axial section of which is similar to that of said refracting pointed elements, and having its base tangential to the bases of said four contiguous refracting intersecting pointed elements.
  • a low luminance lighting panel comprising a plurality of prismatic refracting elements on the outer surface of said panel, said elements being square based pyramids having lateral faces in the form of cylindrical surfaces, the axial cross section of said pyramids through a plane normal to two opposite lateral faces being defined by two arcs symmetric with respect to the axis of symmetry of the pyramid and the centers of which are situated at points beyond said axis of symmetry of the pyramid on a straight line parallel to the plane of the face of the interior surface of the panel and situated above it, said refracting pyramids being arranged on the outer face of the panel in orthogonal rows and columns, the sides of the bases of said continguous pyramids being evenly spaced from one another resulting in two orthogonal series of flat bands equally spaced.
  • a lighting panel according to claim 10 wherein 5 with a plane normal to said exterior face of the panel.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Illuminated Signs And Luminous Advertising (AREA)
  • Optical Elements Other Than Lenses (AREA)
US00245904A 1972-04-20 1972-04-20 Non-luminance lighting panel Expired - Lifetime US3794829A (en)

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JP (1) JPS5443317B2 (it)
DE (1) DE2320247A1 (it)
ES (1) ES414498A1 (it)
FR (1) FR2181010B2 (it)
IT (1) IT1045303B (it)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4069417A (en) * 1975-05-01 1978-01-17 Bausch & Lomb Incorporated Lighting panel having improved refracting elements
US4451872A (en) * 1980-11-26 1984-05-29 Kernforschungsanlage Julich Gesellschaft Mit Beschrankter Haftung Process for the most uniform illumination of a surface by a collimated beam of rays and arrangement for laser diagnostic
US4545007A (en) * 1984-09-12 1985-10-01 Devine Lighting Luminaire with lenticular lens
US4703405A (en) * 1986-07-17 1987-10-27 Ian Lewin Glare reducing lens
US5003448A (en) * 1990-02-07 1991-03-26 K-S-H, Inc. Light-weight lenticular lighting panel
US5124839A (en) * 1989-11-08 1992-06-23 Canon Kabushiki Kaisha Phase-type focusing screen
US6033094A (en) * 1997-10-02 2000-03-07 Fresnel Technologies, Inc. Microlens array for improved illumination patterns
US20040141241A1 (en) * 2002-10-07 2004-07-22 Fresnel Technologies Inc. Imaging lens for infrared cameras
US20050190579A1 (en) * 2004-02-27 2005-09-01 Hon Hai Precision Industry Co., Ltd. Light guide plate including sub-scattering-dots
US20080068716A1 (en) * 2004-07-12 2008-03-20 Dai Nippon Printing Co., Ltd. Diffusing Sheet, Surface Light Source Device, and Transmission Type Display
US20100128351A1 (en) * 2008-11-21 2010-05-27 3M Innovative Properties Company Curved sided cone structures for controlling gain and viewing angle in an optical film

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4004145A (en) * 1975-02-24 1977-01-18 Ignacio Goytisolo Taltavull Nil-luminance lighting panel
FR2454135A1 (fr) * 1979-04-13 1980-11-07 Suisse Horlogerie Structure de surface diffusante pour un guide de lumiere de dispositif d'affichage d'informations
DE102011103981A1 (de) * 2011-06-10 2012-12-13 Siteco Beleuchtungstechnik Gmbh Prismenplatte

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1241886A (en) * 1916-07-12 1917-10-02 Levi Leroy Rowe Lens.
US2474317A (en) * 1949-06-28 Light refracting and transmitting
US2859334A (en) * 1954-09-09 1958-11-04 Edwin F Guth Company Louvers
US3038065A (en) * 1957-05-21 1962-06-05 Holophane Co Inc Prismatic plate
US3096032A (en) * 1959-09-23 1963-07-02 Lighting Products Inc Lighting diffuser
US3234376A (en) * 1963-02-11 1966-02-08 Michael J Ceglia Glare-free lighting fixture
US3566102A (en) * 1967-09-13 1971-02-23 Artcrest Products Co Inc Light panel
US3578967A (en) * 1969-08-27 1971-05-18 Ksh Inc Prismatic lighting panel
US3671101A (en) * 1969-07-25 1972-06-20 Dan M Finch Light control material

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2474317A (en) * 1949-06-28 Light refracting and transmitting
US1241886A (en) * 1916-07-12 1917-10-02 Levi Leroy Rowe Lens.
US2859334A (en) * 1954-09-09 1958-11-04 Edwin F Guth Company Louvers
US3038065A (en) * 1957-05-21 1962-06-05 Holophane Co Inc Prismatic plate
US3096032A (en) * 1959-09-23 1963-07-02 Lighting Products Inc Lighting diffuser
US3234376A (en) * 1963-02-11 1966-02-08 Michael J Ceglia Glare-free lighting fixture
US3566102A (en) * 1967-09-13 1971-02-23 Artcrest Products Co Inc Light panel
US3671101A (en) * 1969-07-25 1972-06-20 Dan M Finch Light control material
US3578967A (en) * 1969-08-27 1971-05-18 Ksh Inc Prismatic lighting panel

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4069417A (en) * 1975-05-01 1978-01-17 Bausch & Lomb Incorporated Lighting panel having improved refracting elements
US4451872A (en) * 1980-11-26 1984-05-29 Kernforschungsanlage Julich Gesellschaft Mit Beschrankter Haftung Process for the most uniform illumination of a surface by a collimated beam of rays and arrangement for laser diagnostic
US4545007A (en) * 1984-09-12 1985-10-01 Devine Lighting Luminaire with lenticular lens
US4703405A (en) * 1986-07-17 1987-10-27 Ian Lewin Glare reducing lens
US5124839A (en) * 1989-11-08 1992-06-23 Canon Kabushiki Kaisha Phase-type focusing screen
US5003448A (en) * 1990-02-07 1991-03-26 K-S-H, Inc. Light-weight lenticular lighting panel
AU630519B2 (en) * 1990-02-07 1992-10-29 K-S-H Inc. Light-weight lenticular lighting panel
US6033094A (en) * 1997-10-02 2000-03-07 Fresnel Technologies, Inc. Microlens array for improved illumination patterns
US20040141241A1 (en) * 2002-10-07 2004-07-22 Fresnel Technologies Inc. Imaging lens for infrared cameras
US20070002467A1 (en) * 2002-10-07 2007-01-04 Fresnel Technologies Inc. Imaging lens for infrared cameras
US7187505B2 (en) 2002-10-07 2007-03-06 Fresnel Technologies, Inc. Imaging lens for infrared cameras
US7474477B2 (en) 2002-10-07 2009-01-06 Fresnel Technologies, Inc. Imaging lens for infrared cameras
US20050190579A1 (en) * 2004-02-27 2005-09-01 Hon Hai Precision Industry Co., Ltd. Light guide plate including sub-scattering-dots
US7290921B2 (en) * 2004-02-27 2007-11-06 Hon Hai Precision Industry Co., Ltd. Light guide plate including sub-scattering-dots
US20080068716A1 (en) * 2004-07-12 2008-03-20 Dai Nippon Printing Co., Ltd. Diffusing Sheet, Surface Light Source Device, and Transmission Type Display
US7510308B2 (en) * 2004-07-12 2009-03-31 Dai Nippon Printing Co., Ltd. Diffusing sheet, surface light source device, and transmission type display
US20100128351A1 (en) * 2008-11-21 2010-05-27 3M Innovative Properties Company Curved sided cone structures for controlling gain and viewing angle in an optical film
CN102216814A (zh) * 2008-11-21 2011-10-12 3M创新有限公司 用于控制光学膜中的增益和视角的弯曲侧面圆锥结构

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Publication number Publication date
JPS4920964A (it) 1974-02-23
IT1045303B (it) 1980-05-10
FR2181010A2 (it) 1973-11-30
FR2181010B2 (it) 1974-11-08
DE2320247A1 (de) 1973-10-25
JPS5443317B2 (it) 1979-12-19
ES414498A1 (es) 1976-05-01

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