EP0814453A2 - Beleuchtungsvorrichtung - Google Patents
Beleuchtungsvorrichtung Download PDFInfo
- Publication number
- EP0814453A2 EP0814453A2 EP97201731A EP97201731A EP0814453A2 EP 0814453 A2 EP0814453 A2 EP 0814453A2 EP 97201731 A EP97201731 A EP 97201731A EP 97201731 A EP97201731 A EP 97201731A EP 0814453 A2 EP0814453 A2 EP 0814453A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- light
- light source
- linear
- sheet
- lens
- 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.)
- Withdrawn
Links
Images
Classifications
-
- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09F—DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS
- G09F13/00—Illuminated signs; Luminous advertising
- G09F13/04—Signs, boards or panels, illuminated from behind the insignia
- G09F13/14—Arrangements of reflectors therein
-
- 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
-
- 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
- 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
- F21V13/12—Combinations of only three kinds of elements
-
- 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
-
- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09F—DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS
- G09F13/00—Illuminated signs; Luminous advertising
- G09F13/04—Signs, boards or panels, illuminated from behind the insignia
- G09F13/0409—Arrangements for homogeneous illumination of the display surface, e.g. using a layer having a non-uniform transparency
-
- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09F—DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS
- G09F13/00—Illuminated signs; Luminous advertising
- G09F13/04—Signs, boards or panels, illuminated from behind the insignia
- G09F13/0418—Constructional details
- G09F13/0422—Reflectors
-
- 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
-
- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09F—DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS
- G09F13/00—Illuminated signs; Luminous advertising
- G09F13/04—Signs, boards or panels, illuminated from behind the insignia
- G09F13/14—Arrangements of reflectors therein
- G09F2013/145—Arrangements of reflectors therein curved reflectors
Definitions
- the present invention relates to a light apparatus useful for illuminating transparent displays.
- Illuminated displays which display images carried on a transparent substrate are well known, and are often used as advertising or other displays. Such displays typically have a housing which is enclosed except for a front light opening, across which the transparency carrying the image is to be positioned. A light source is positioned within the housing and behind the transparency. A plurality of elongated light sources, such as fluorescent tubes, are usually used as the light source. In order that the light source itself is not observed through the image carrying transparency, a diffuser in the form of a diffusing sheet, may be positioned between the light source and the transparency. Displays of the foregoing type may be used for transparencies carrying a regular two-dimensional image, such as formed from a photograph. More recently it has been known to use a transparency carrying an integral image.
- Integral image elements which use a lenticular lens sheet, fly's eye lens sheet, or barrier strip sheet and a three-dimensional integral image aligned with the sheet, so that a user can view the three-dimensional image without any special glasses or other equipment, are known.
- imaging elements and their construction are described in "Three-Dimensional Imaging Techniques" by Takanori Okoshi, Academic Press, Inc., New York, 1976.
- Integral image elements having a lenticular lens sheet are also described in the following Unites States patents: US 5,391,254; US 5,424,533; US 5,241,608; US 5,455,689; US 5,276,478; US 5,391,254; US 5,424,533 and others; as well as allowed US patent application Serial Number 07/931,744.
- Integral image elements with lenticular lens sheets use interlaced vertical image slices which, in the case of a three-dimensional integral image, are aligned with the lenticules so that a three-dimensional image is viewable when the lenticules are vertically oriented with respect to a viewer's eyes.
- the image may be conveniently laminated (that is, adhered) to an integral or lenticular lens sheet.
- Similar integral image elements such as described in US 3,268,238 and US 3,538,632, can be used to convey a number of individual two-dimensional scenes (such as unrelated scenes or a sequence of scenes depicting motion) rather than one or more three-dimensional images, the scenes being viewable at different respective angles with respect to the element.
- the present invention realizes that even with simple reflectors or diffusers, illumination intensity at a location where the transparency is to be positioned, must necessarily decrease at positions which are between light sources. This is so since luminance must decrease with distance from any light source.
- Previous attempts to design various reflectors or diffusers which try to spread light more evenly between light sources can only have limited success.
- the present invention takes a different approach in recognizing that the source of the problem is simply the space that exists where there is no light source (such as between a plurality of light sources). While this could be overcome by providing more light sources, such an approach may not be practical given construction and operations costs. However, the present invention attempts to obtain an equivalent effect.
- the present invention then provides a light apparatus which in a first aspect comprises:
- the light apparatus comprises:
- Another aspect of the present invention provides a light source, lenticular lens sheet behind the light source with lens surfaces facing the light source, and reflector behind the lens surfaces to redirect rearwardly emitted light, to the forward direction.
- a light apparatus of the present invention can provide illumination of good uniformity to an image bearing transparency positioned forward of the light source, even though there may be considerable area behind the transparency at which there is no actual light source.
- illumination uniformity can be improved.
- the same illumination uniformity can be retained and the number of light sources reduced.
- FIG. 1 there is shown a lateral cross-section of a light apparatus similar to that of FIG. 2, but not using a lenticular lens sheet as used in the present invention.
- the apparatus shown comprises a plurality of linear, parallel, identical light sources 36a, 36b, such as linear fluorescent bulbs (extending in a direction perpendicular to the plane of the drawing).
- a diffuser sheet is positioned forward of light sources 36a, 36b, and forward and adjacent diffuser sheet 18 is a transparency carrying an image for viewing from a further forward position.
- Reflector 8 is a flat specular reflector (although the same type of result is obtained with a diffuse reflector). Note that rays 9 from a back side of light source 36a necessarily spread outward as they travel toward reflector 8, and further spread after their reflection from reflector 8. Thus, while these reflected rays 9 will increase the total light received at diffuser 18 than would be received simply from rays 14, the intensity of illumination on diffuser 18 will necessarily decrease moving in a lateral direction away from light source 36a toward light source 36b. A similar result will be obtained from light source 36b, the net result being that even with reflector 9 present, illumination on diffuser 18 still necessarily decreases moving in a direction away from light sources 36a, 36b toward a mid-point 18a between those sources.
- Apparatus 10 includes an opaque housing 12 except for a front light opening 16 through which light can pass.
- Light opening 16 is defined by a light transmitting diffuser 18 (such as a translucent white plastic sheet) positioned to extend across the area defined by a front periphery 14. and a transparency 20 positioned adjacent and forward of diffuser 18.
- Transparency 20 is co-extensive with diffuser 18 and carries a visible image for display. Diffuser 18 and transparency 20 are shown mostly cut away in FIG. 2 so that the inside of light apparatus 10 can be more clearly seen.
- Transparency 20 can carry any type of image including a typical ordinary two-dimensional image (such as obtained from enlarging a conventional photograph) or may carry an integral image as described further below.
- a plurality of identical linear light sources 36 are positioned within housing 12 and emit light in a forward direction toward diffuser 18, and in a rearward direction.
- a lenticular lens sheet 30, of well known construction is positioned adjacent an opaque back wall 35 of housing 12.
- Lens sheet 30 has a flat back surface 34 and a plurality of parallel, elongated and linear cylindrical lens surfaces 32 on a front side.
- Back surface 34 is preferably itself reflecting. To accomplish this it is preferably a somewhat diffuse reflecting surface which is integral with the remainder of lens sheet 30, such as may be obtained by a finely abrasive treatment of back surface 34 (for example, by fine sandblasting).
- back surface 34 can simply result from back surface 34 being flat and polished, and then solely relying upon internal reflection at back surface 34 (although this is less preferred).
- a separate reflecting layer (such as a reflecting metal or metal oxide coating) could be provided to make back surface 34 reflecting.
- back wall 35 could be forward reflecting.
- Such a separate reflecting layer is preferably positioned immediately adjacent back surface 34. It will be appreciated that back wall 35 could be omitted, particularly for example, if back surface 34 has an adjacent reflecting metal layer.
- lens surfaces 32 are in the form of a pattern which follows the contour of the light sources 36.
- contour of the light sources is referenced the outline of the two-dimensional direct projection of the light sources 36 toward front light opening 16 (by direct projection is meant that rays are traced from the back toward the front in a direction 90 degrees to the front light opening 16). That is, the light sources 36 have a linear contour, therefore the lens surfaces 32 follow this contour and are therefore arranged in a linear pattern parallel to light sources 36.
- transparency 20 can be viewed from a forward direction when light sources 36 are energized.
- following does not have to be precise (that is, it does not have to be parallel to the contour).
- FIGS. 4 and 5 The applicable optical paths for the first and second satellite images for the lenticular lens sheet 30, are shown in FIGS. 4 and 5, respectively.
- a ray 40 enters a lenticule 41 and strikes the planar back surface 34 causing an illumination of the intercept point 44.
- Point 44 becomes an object for the next adjacent lenticule 42 and light is refracted from lenticule 42 along the refracted path 45.
- the initial angle of incidence " a" to a centerline 41c and the refractive index " n" of the lens sheet 30 relative to the external refractive index number " n o " determines by Snell's law the angle " b" .
- the thickness " t" of lens sheet 30 will be substantially equal to the focal length of the lens surface 32. Such thickness is measured from the top of the convex lens surface (that is, it will be the maximum thickness). However, t need not be equal to the focal length, and could be modified to alter the distribution of intercept points resulting from the first and second satellite images if desired. Ray 40 is thereby refracted to ray 40r. Point 44 is the object of lenticule 42 at an angle " c" from its centerline 42c.
- a ray 60 is the reflected path of photons emitted from point 44 toward the lens surface 32 of lenticule 42. Again by Snell's law, ray 60 is refracted to a new angle " d" as ray 60r.
- the spacing of lenticules 41 and 42 and other similar lenticules in the lens sheet 30 is " p" .
- the values of a , b , c and d can then be determined to be given in equations (2), (5) and (7) below from the following geometric relationships: therefore: Also: and: therefore: Also: therefore: Also: therefore:
- Figure 5 is similar to Figure 4 except that the second satellite image is analyzed.
- the equations given earlier are then expanded to include by the same reasoning, this second satellite case:
- the surface treatment of the back surface 34 of lens sheet 30 will affect the efficiency of light transmitted along refracted ray 60r.
- a diffuse white surface is preferred over a plane unfinished surface.
- a diffuse "sandblasted" back surface 34 may be better than a plane surface polished surface.
- the addition of a metal or metal oxide layer behind back surface 34 can be used to improve reflectivity.
- FIG. 6 is a portion of the view shown in FIG. 3 illustrating the first satellite image.
- the incident angle is a . Therefore, the intercept distance from x O (the central axis of the center of light source 36) is: where g is the distance from the tube center to the lenticular plane 002.
- the photon refracts away from lenticular lens sheet 30 at angle d on a new ray 60r.
- This photon "hits" diffuser 18 at point 70 located at a distance " k 1 " from x o .
- FIG. 7 is a view the same as in FIG. 6 but illustrating the paths of additional light rays.
- FIG. 7 a series of photon paths at incrementally increasing angles 102, 103, 104, 105 result in refracted photon paths 102r, 103r, 104r, 105r respectively, and intercept diffuser 18 at "hit" points 112, 113, 114, 115, respectively.
- the distances k 1 in FIG. 6 corresponding to each of points 112, 113, 114, 115, can be calculated and plotted for display. An arrangement of equally distant points would be seen as a uniformly illuminated section of the diffuse plane.
- FIG. 7 It is particularly instructive from FIG. 7 to note that light from light source 36 emitted in a backward direction, is being refocussed by lenticular lens sheet 30 at a position between adjacent light sources 36. Light directed backward is not simply being reflected as would be the case with a simple planar reflector or reflected and scattered as would occur with a diffuse planar reflecting surface only. Thus, illumination at a position on diffuser 18 midway between adjacent light sources 36 can actually be increased such that illumination on diffuser 18 does not necessarily decrease toward a position midway between adjacent light sources 36.
- FIG. 8 this is a view the same as FIG. 7 but showing the a similar set of photon paths emitted from a front side of light source 36 and directly intercept diffuser 18.
- paths 201, 202, 203, 204 are normal to the surface of light source 369, but directed forward toward diffuser 18.
- the respective intercepts with diffuser 18 are at points 211, 212, 213, 214.
- These intercepts, k 0 can be calculated as follows:
- the values of a can be the same as the earlier, analysis of refracted photon paths, but are measured clockwise from the Y axis 291 of the coordinate system centered at x 0 .
- the previously mentioned spreadsheet can calculate and plot the intercepts "hit" points 211, 212, 213, and 214 and the like by the addition of the appropriate equations.
- the light ray intercepts between adjacent light sources 36 is plotted in FIG. 8A.
- the vertical axis is the ratio of box thickness g + h (which passes through the center of the lamp), normalized to the lamp spacing S b .
- the horizontal axis is position as a ratio of lamp spacing (thus, another lamp would be present at position 1). Note that unlike the use of a flat reflector, such as shown and described above in connection with Figure 1, that the density of intercepts does not fall to a minimum at a position midway between adjacent light sources 36, but increases because of the effect of light being redirected by the lenticular lens sheet 30.
- the intercept density may not have a one-to-one correspondence with light intensity though, because of imperfections in the lenticular lens sheet 30 and efficiency of reflectance from the back surface 34. Of course, these are characteristics that can be controlled to some degree during production to optimize performance or cost.
- FIG. 9 there is shown a lateral cross-section of another light apparatus 10a of the present invention.
- Apparatus 10a is similar in construction to apparatus 10 of FIGS. 2 and 3.
- apparatus 10a has a curved image carrying transparency 20a positioned in front of a curved diffuser 18a, both of which extend to a back wall 35a (note that both transparency 20a and diffuser 18a are curved concavely about the direction of linear light sources 36).
- Two linear light sources 36 are positioned behind diffuser 18a and forward of two lenticular lens sheets 30a.
- Each lenticular lens sheet 30a is the same as sheet 30 in apparatus 10, but each only extends laterally outward from behind its corresponding light source 36 (that is, there is no lenticular lens sheet behind and between the two light sources 36. It will be appreciated that by proper adjustment of the curvature of diffuser 18a and transparency 20a, and the positioning of light sources 36, fairly uniform illumination on diffuser 18 can be obtained.
- FIG. 10 illustrates a different pattern of lenticular lens elements.
- a light source 300 is provided which has a circular contour, such as a spherical light source.
- Lenticular lens sheet 30b in this case has parallel, elongated, convex lens surfaces 32b, which follow the circular contour of light source 300 and thus form a pattern of concentric circles.
- "elongated" in the context of the lens surface shapes does not require that they be linear, unless the contrary is indicated.
- Lenticular lens sheet 30b otherwise may be constructed in any of the manners described in connection with lens sheet 30 described above.
- a diffuser and transparency carrying an image could be placed in sequence in front of such a light source.
- such a light source 300 and lens sheet 30b could be used with our without a diffuser as a light source to project light forwardly.
- FIG. 11 shows a lateral cross-section across an apparatus incorporating the arrangement shown in FIG. 10.
- a housing 12b is opaque but has a front light opening defined by a convex lens in the form of a light transmitting Fresnel lens 302.
- Housing 12b includes a back wall 35b against which lens sheet 30b is positioned.
- Back wall 35b may have a forwardly reflecting surface adjacent lens sheet 30b, similar to back wall 35 described above.
- the light assembly 10b of FIG. 11 may have a diffuser positioned adjacent and in front of Fresnel lens 302.
- a transparency carrying an image may be positioned adjacent and in front of Fresnel lens 302 if it is desired to use light assembly 10b to display an image carried by such a transparency.
- the transparency can be omitted and the light assembly 10b, with or without diffuser, used as a forward projecting light source for other purposes.
- Fresnel lens 302 tends to collimate light passing forwardly through it.
- the lenticular lens sheets have been described as having a "convex" lens surfaces. It will be understood that such lens surfaces may be physical convex surfaces (which is preferred), in the sense that they have a physical convexity. Alternatively, the convex lens surfaces can be functional ones, in the sens that the optical effect provided is the same as that provided by physical convex lens surfaces of leticules.
- lens sheets which may be physically flat on either side but use regions of varying indices of refraction through its volume configured in such a way as to provide (in conjunction with the surfaces of the sheet, such as a curved external surface, flat external surface or some other shape) the same optical deflection of light rays as would be provided by a lenticular lens sheet with physical convex lens surfaces.
- the back surface of the lenticular lens sheet may also be curved so as to either strengthen the lens effect or compensate for the curved focal plain which may be inherent in the lens construction. Consequently, the curvature on the back side may be of such a shape as to match the curvature of the focal plain of the lens.
- the entire lens sheet such as lens sheet 30, may be curved or otherwise shaped, such as curved concavely or convexly about an axis parallel to that of a linear light source.
- a linear light source in this application, it will be appreciated that such a source includes a line of individual sources (such as a line of spherical incandescent bulbs).
- the light distribution to be received on the diffuser 18 could also be altered by altering the characteristics of the reflecting back surface 34.
- bands of diffuse reflecting areas 400 could be provided, as shown in FIGS. 12 and 13, if it was desired to provide more diffuse satellite images.
- FIG. 12 shows the effect on the first satellite images while FIG. 13 shows the effect on the second satellite image.
- areas 400 could be colored if color effects were desired, or they could be angled zones if other effects were desired.
- an image can be a conventional two-dimensional image obtained from enlarging a conventional photograph or the like.
- an image may particularly be an integral image for use with a lenticular lens sheet (thus, it will have interlaced strips from multiple two-dimensional images, as described above; integral images specifically constructed for lenticular lens sheets are sometimes referenced as "lenticular images").
- the strips are to be aligned with individual lenses of an integral lens sheet so that each of the images is viewable when a user's eyes are at the correct angle relative to the imaging element.
- the integral image can be one or more three-dimensional images, one or more two dimensional images, or any combination of the foregoing.
- a three-dimensional image is meant an integral image which, when viewed through the lens, has a visible depth element.
- a depth element means the ability to at least partially look around an object in the scene. This can be obtained by interlacing lines from different perspective views of the same scene (that is, views from different angular positions with respect to the scene).
- a three-dimensional image necessarily includes at least two views of a scene.
- a two-dimensional image is referenced an image which, when viewed in the final product, does not have any viewable depth element.
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- Securing Globes, Refractors, Reflectors Or The Like (AREA)
- Optical Elements Other Than Lenses (AREA)
- Planar Illumination Modules (AREA)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US66575496A | 1996-06-18 | 1996-06-18 | |
US665754 | 1996-06-18 |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0814453A2 true EP0814453A2 (de) | 1997-12-29 |
EP0814453A3 EP0814453A3 (de) | 1999-07-28 |
Family
ID=24671450
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP97201731A Withdrawn EP0814453A3 (de) | 1996-06-18 | 1997-06-07 | Beleuchtungsvorrichtung |
Country Status (2)
Country | Link |
---|---|
EP (1) | EP0814453A3 (de) |
JP (1) | JPH1082973A (de) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2012159545A1 (zh) * | 2011-05-23 | 2012-11-29 | 北京莱易龙光电科技有限公司 | 一种led灯箱 |
WO2014179101A1 (en) * | 2013-05-02 | 2014-11-06 | 3M Innovative Properties Company | Self illuminated shaped and two-sided signage for printed graphics |
CN111837073A (zh) * | 2018-03-20 | 2020-10-27 | 索尼公司 | 图像显示设备 |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP4522938B2 (ja) * | 2005-10-07 | 2010-08-11 | 株式会社クラレ | 照明装置これが備える光制御部材及びこれを用いた画像表示装置 |
JP4563294B2 (ja) * | 2005-10-07 | 2010-10-13 | 株式会社クラレ | 照明装置これが備える光制御部材及びこれを用いた画像表示装置 |
CN110070806A (zh) * | 2019-03-31 | 2019-07-30 | 方迪勇 | 一种模块化大型灯箱的构成方法 |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5134553A (en) * | 1990-10-17 | 1992-07-28 | Toshiaki Nakagawa | Illuminating device |
US5282117A (en) * | 1990-08-24 | 1994-01-25 | Fritts Robert W | Light leveling means for fluorescent backlit displays or the like |
US5365411A (en) * | 1993-01-06 | 1994-11-15 | Kaufel Group Ltd. | Exit signs with LED illumination |
GB2310525A (en) * | 1996-02-24 | 1997-08-27 | Ronnie Revell | Illuminated display device |
-
1997
- 1997-06-07 EP EP97201731A patent/EP0814453A3/de not_active Withdrawn
- 1997-06-17 JP JP9159805A patent/JPH1082973A/ja active Pending
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5282117A (en) * | 1990-08-24 | 1994-01-25 | Fritts Robert W | Light leveling means for fluorescent backlit displays or the like |
US5134553A (en) * | 1990-10-17 | 1992-07-28 | Toshiaki Nakagawa | Illuminating device |
US5365411A (en) * | 1993-01-06 | 1994-11-15 | Kaufel Group Ltd. | Exit signs with LED illumination |
GB2310525A (en) * | 1996-02-24 | 1997-08-27 | Ronnie Revell | Illuminated display device |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2012159545A1 (zh) * | 2011-05-23 | 2012-11-29 | 北京莱易龙光电科技有限公司 | 一种led灯箱 |
WO2014179101A1 (en) * | 2013-05-02 | 2014-11-06 | 3M Innovative Properties Company | Self illuminated shaped and two-sided signage for printed graphics |
US9082326B2 (en) | 2013-05-02 | 2015-07-14 | 3M Innovative Properties Company | Self illuminated shaped and two-sided signage for printed graphics |
CN105144272A (zh) * | 2013-05-02 | 2015-12-09 | 3M创新有限公司 | 用于印刷图形的自发光的成型和双侧标牌 |
US9449541B2 (en) | 2013-05-02 | 2016-09-20 | 3M Innovative Properties Company | Self illuminated shaped and two-sided signage for printed graphics |
CN105144272B (zh) * | 2013-05-02 | 2018-01-16 | 3M创新有限公司 | 用于印刷图形的自发光的成型和双侧标牌 |
CN111837073A (zh) * | 2018-03-20 | 2020-10-27 | 索尼公司 | 图像显示设备 |
CN111837073B (zh) * | 2018-03-20 | 2022-10-11 | 索尼公司 | 图像显示设备 |
Also Published As
Publication number | Publication date |
---|---|
EP0814453A3 (de) | 1999-07-28 |
JPH1082973A (ja) | 1998-03-31 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US4767186A (en) | Front projection screen with rear light concentrating lens array | |
CN101228391B (zh) | 用于背光源和前灯的聚光本领-保持的照明光学器件 | |
JP4922935B2 (ja) | 光学フィルム、構成要素または導波管の製作に使用するために基板にキャビティを切削または形成する方法 | |
US5608550A (en) | Front-lit liquid crystal display having brightness enhancing film with microridges which directs light through the display to a reflector | |
US7876489B2 (en) | Display apparatus with optical cavities | |
JP4349902B2 (ja) | 光方向変更膜および光方向変更膜システム | |
EP0686247B1 (de) | Aus einem prismatischen lichtwellenleiter bstehende leuchte mit wirksam gerichteter ausstrahlung | |
KR0145710B1 (ko) | 디스플레이 장치용 조명 시스템 | |
KR900001520B1 (ko) | 후면 투사스크린 | |
US3523717A (en) | Composite back projection screen | |
EP3553588A1 (de) | System zur verwendung bei der abbildung in der luft | |
US6170971B1 (en) | Indicating light display having several light sources | |
EP0430470B1 (de) | Reflektor und eine diesen enthaltende Beleuchtungsvorrichtung | |
US4241980A (en) | Beam emission control means | |
US11649944B2 (en) | Lighting device | |
EP0989356A1 (de) | Vorrichtung zur Beleuchtung einer Fläche in mehrfache Richtungen in konzentrieter Weise | |
US4538216A (en) | Lighting apparatus | |
US20220065425A1 (en) | A lighting device | |
US3578841A (en) | Rear projection screen | |
EP0814453A2 (de) | Beleuchtungsvorrichtung | |
US20150043220A1 (en) | Using micro optical elements for depth perception in luminescent figurative structures illuminated by point sources | |
US20150204518A1 (en) | Light-Emitting Diode Lamp | |
CN105917165B (zh) | 具有光漫射器的照明器 | |
EP4051957B1 (de) | Beleuchtungsvorrichtung zur bereitstellung einer funkelnden erscheinung | |
JP3676425B2 (ja) | 導光板 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
AK | Designated contracting states |
Kind code of ref document: A2 Designated state(s): DE FR GB |
|
PUAL | Search report despatched |
Free format text: ORIGINAL CODE: 0009013 |
|
RIC1 | Information provided on ipc code assigned before grant |
Free format text: 6G 09F 13/04 A, 6F 21V 7/00 B, 6G 09F 13/14 B, 6F 21S 3/02 B |
|
AK | Designated contracting states |
Kind code of ref document: A3 Designated state(s): AT BE CH DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE |
|
AKX | Designation fees paid |
Free format text: DE FR GB |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN |
|
18D | Application deemed to be withdrawn |
Effective date: 19990608 |