Lighted Display Case with Remote Light Source
Lighted display case with remote light source comprises a container having contents for display. A solid fiber optic luminaire is at least partially mounted within the container, having an elongated side-light emitting portion for emitting light from the side of the luminaire onto contents in an interior of the display case. The side-light emitting portion comprises an extractor of light arranged to preferentially extract light from the luminaire and direct the light to at least one target area of said contents. The portion may be rotatable about its own longitudinal axis. A single side-light emitting portion may be arranged to illuminate a target area on one of its lateral sides, and another target area on another lateral side. A single lamp may provide light to first and second luminaires arranged to illuminate a target area on one of its lateral sides, and another target area on another lateral side.
The present invention relates to a lighted display case with a remote light source. More particularly, the invention relates to such a display case in which light for illuminating contents of the case is provided by a fiber optic luminaire.
BACKGROUND OF THE INVENTIONTraditional display cases used to display retail merchandise or items of value such as in a museum often employ fluorescent or (filamented) halogen lamps to light the items. Such lamps have various disadvantages for lighting tightly confined spaces. Among these is the fact that fluorescent tubes emit light in all directions and emit moderate levels of ultraviolet light. When taken together with their ballasts, the complete lighting system can produce a significant amount of heat, especially when confined in an enclosure. Halogen or incandescent lamps similarly have the disadvantages of directing a large amount of heat into the display area. Although a halogen lamp is often accompanied by a special dichroic reflector which concentrates visible light but not infrared light in the forward direction, the confined nature of a display case often ends up trapping this undirected infrared energy anyway. This usually results in an excessive heat buildup or the necessity to remove this heat by energy-demanding means such as air conditioning or forced air convection. Even when no special measures are taken to transport the unneeded heat away, the heat is usually an inconvenience at best and a nuisance at worst to the customers or patrons who must view the contents of the case.
The need exists for an energy-efficient way to light the merchandise or items contained in a display case while not introducing any harmful ultraviolet or unnecessary infrared energy into the display area, and to forgo the need to introduce costly heat-control devices.
Fluorescent tubes, while more energy-efficient than tungsten-halogen lamps, have other disadvantages as well. They are fragile and contain hazardous substances such as mercury and phosphors. If broken, the glass shards are a severe safety hazard. Due to the manner in which such tubes must be mounted in the typical display case, changing the tubes can be an awkward and labor-intensive operation requiring the careful removal and reinsertion of a fragile item in a confined space. Tungsten-halogen lamps, though compact, are numerous when employed in a typical display case. As a result, they need to be replaced much more frequently than their fluorescent counterparts resulting in either an uneven lighting situation when they fail, or a costly manual maintenance operation to replace the failed lamps with great promptness.
The need exists to allow for a convenient way to maintain or re-lamp a display-case lighting system which does not suffer from these disadvantages.
BRIEF SUMMARY OF THE INVENTIONThe disclosed invention provides the foregoing benefits and others such as requiring less electrical power to provide comparable amounts of light even apart from the maintenance and energy transport consideration outlined above.
SUMMARY OF THE INVENTIONIn accordance with one form of invention, a lighted display case with remote light source is presented which comprises a container having contents for display. A solid fiber optic luminaire is at least partially mounted within the container. The luminaire has an elongated side-light emitting portion for emitting light from the side of the luminaire onto contents in an interior of the display case. The side-light emitting portion comprises an extractor of light arranged to preferentially extract light from the luminaire and direct the light in at least one radial direction along the length of the side-light emitting portion to at least one target area of said contents along a longitudinal axis of the side-light emitting portion. The extractor of the light comprises first and second light-extraction regions.
In a first embodiment, the container has first and second view ports intended to allow persons outside the container to view contents displayed in the interior of the container. The first view port is on one lateral side of the side-light emitting portion and the second view port is on a second lateral side of said portion. A light-delivery system provides light to the fiber optic luminaire, having a light source mounted remotely from the container. The luminaire is arranged to illuminate first and second separate target areas of said contents of the display case. The first target area is visible through the first view port and the second target area is visible through the second view port. The first and second target areas are illuminated by the first and second light-extraction regions. The first and second light-extraction regions are spaced from each other around a perimeter of the side-light emitting portion taken orthogonally to main optical axis of said side-light emitting portion.
In a second embodiment, the lighted display case remote light source is presented which comprises a container with a view port intended to allow persons outside the container to view contents displayed in the interior of the container. The side-light emitting portion of the luminaire is rotatable about its own longitudinal axis for directing the aim of the light emitted therefrom to various radial directions about said axis.
In the third embodiment, a lighted display case with remote light source is presented which comprises a container having contents for display. First and second solid fiber optic luminaires are at least partially mounted within the container. Side-light emitting portions of the first and second luminaires are mounted parallel to each other and are respectively positioned to illuminate a target area on one side of the luminaires and a laterally adjacent target area on another side of the luminaires.
BRIEF DESCRIPTION OF THE DRAWINGSIn the drawings, like reference numerals refer to like parts.
Referring to
As best shown in
Clamp 44 (
A channel 48 may be conveniently used for mounting the luminaires in a display case. As shown in
As shown in
Luminaires 30 and 32 may preferably comprise solid fiber optic structures, such as an acrylic polymer rod.
Feed-through 76 comprises a central cylindrical penetrating part 79 ensheathing fiber optic structure 78, upper and lower compression fittings 80 and 82, and O-rings 81 and 83.
Compression fitting 80 includes a threaded nut 80a pressing compressible O-ring 81 into sealed relation against external wall 58 of container 11 and penetrating part 79. Compression fitting 80 further includes a threaded nut 80b for compressing resilient material 80c into sealed relation against penetrating part 79 and fiber optic structure 78. Compression fitting 80 cooperates with compression fitting 82, whose parts 82a, 82b, 82c and O-ring 83 correspond to parts 80a, 80b, 80c and O-ring 81 of compression fitting 80. In particular, O-rings 81 and 83 become compressed only when nuts 80a and 82a are rotated until they are sufficiently close to each other.
As just described, feed-through 79 seals fiber optic structure 78 against both internal and external walls 56 and 58 of the container.
More preferably, luminaires will be releasably held in any of several predetermined positions, such that the luminaires can be rotated by hand alone into any of such positions. Such releasable holding can be accomplished as follows. In
Secondary optics, such as a Fresnel lens, becomes especially valuable when the intensity (lumens/steradian) from a round rod luminaire is insufficient to achieve a desired target surface illuminance. This typically occurs when the angle of light hitting the target surface area is large, which is typical when the freezer door is wide (e.g., 91 cm) and the distance to the target surface is small (e.g., 10 cm). The Fresnel lens can increase the intensity of the light directed toward the target surface and thereby increase the target surface illuminance. With a round rod luminaire, the peak intensity occurs when the radial paint stripe width (e.g., the illustrated radial angle 101 for a light extractor) is approximately 20 to 30 degrees, so the Fresnel lens is often used with narrow paint stripes.
Using a single luminaire as in
In
In
Returning to
The longitudinal dimension of gaps 113a and 114a of
The light extractor on a luminaire can be arranged to preferentially extract light from the luminaire and direct such light in multiple radial directions along the length of the side-light emitting portion. This is shown in
A preferred light extractor comprises a layer of paint exhibiting Lambertian extraction and having a binder with a refractive index about the same as, or greater than that of, a core. Suitable light-extraction particles are added to the paint, such as titanium dioxide or many other materials as will be apparent to those of ordinary skill in the art. Preferably, the paint is an organic solvent-based paint.
Extractors of paint output most of their light in a preferred radial direction from an elongated luminaire. A textured type of extractor could alternatively be used, wherein the surface of the luminaire is textured by molding, laser etching, or chemical etching. Some textured extractors can extract light with a higher directionality than paint, but may introduce artifacts into the light output, which requires a diffuser to mask from view.
Preferred light-extractors and formulation of gradients of their efficiency along an elongated luminaire, and along a radial perimeter of a luminaire are described in the following U.S. patent applications having some common inventors with the present application, and assigned to the same joint owners as the present application:
-
- U.S. patent application Ser. No. 11/366,711 filed 2 Mar. 2006 for Luminaire with Improved Lateral Illuminance Control by W. Cassarly et al.
- U.S. patent application Ser. No. 11/108,279 filed 18 Apr. 2005 for Efficient Luminaire with Directional Side-Light Extraction by W. Cassarly et al.
The present joint owners of the foregoing applications and of the present application are Fiberstars, Inc. and Optical Research Associates. The entireties of the disclosures of the foregoing applications are hereby incorporated by reference.
Various benefits arise because the luminaires in both
Additionally, the fiber optic luminaires more efficiently direct light onto desired target areas. This is due to their extraction of light in a highly directional manner. This can be appreciated from referring to light-extraction regions 120 and 121 (
Further, fiber optic luminaires of one aspect of the invention may deliver light to the target area more efficiently than fluorescent lamps since they can have smaller cross-sectional dimension(s) and are thereby less likely to block light which strikes a reflector. For instance, a fiber optic luminaire typically would be about 19 mm, or preferably 15 mm, or less in diameter (for a round luminaire) compared with 25-37 mm diameter for a typical fluorescent lamp. Because the reflector must often be placed close to the fluorescent lamp, a substantial amount of light will restrike the fluorescent lamp after hitting the reflector. The slimmer luminaire can better accommodate use of reflectors, such as reflectors 34 and 36.
HID lamp 182 and collector 184 are conveniently protected by a housing 190 mounted atop container 11. The housing may include an air intake with dust filter (not shown) and a hot air exhaust fan (not shown). This arrangement does not leave exposed outside the container any flexible fiber optic cables that could potentially be damaged if bent or kinked, for instance.
While the invention has been described with respect to specific embodiments by way of illustration, many modifications and changes will occur to those skilled in the art. For instance, it will be routine in the art to incorporate infra-red or ultra-violet filters in the described fiber optic light-delivery systems where useful. Additionally, directions used herein, such as “top” or “downwardly,” indicate directions that are exemplary, and are not to be construed as limiting. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true scope and spirit of the invention.
Claims
1. A lighted display case with remote light source, comprising:
- a) a container having contents for display;
- b) a solid fiber optic luminaire at least partially mounted within the container; the luminaire having an elongated side-light emitting portion for emitting light from the side of the luminaire onto contents in an interior of the display case; the side-light emitting portion comprising an extractor of light arranged to preferentially extract light from the luminaire and direct said light in at least one radial direction along the length of the side-light emitting portion to at least one target area of said contents along a longitudinal axis of the side-light emitting portion;
- c) the extractor of light comprising first and second light-extraction regions;
- d) the container having a first and second view ports intended to allow persons outside the container to view contents displayed in the interior of the container; the first view port being on one lateral side of the side-light emitting portion and the second view port being on a second lateral side of said portion;
- e) a light-delivery system for providing light to the fiber optic luminaire; the light-delivery system having a light source mounted remotely from the container;
- f) the luminaire being arranged to illuminate first and second separate target areas of said contents of the display case; the first target area being visible through the first view port and the second target area being visible through the second view port; the first and second target being illuminated by the first and second light-extraction regions; and
- g) the first and second light-extraction regions being spaced from each other around a perimeter of the side-light emitting portion taken orthogonally to main optical axis of said side-light emitting portion.
2. The lighted display case of claim 1, wherein:
- a) the container is open to its ambient; and
- b) the interior of the container is maintained within 5 C of the temperature of the ambient.
3. The display case of claim 1, wherein:
- a) the view ports having a maximum dimension; and
- b) the side-light emitting portion of the luminaire extends across the majority of said maximum dimension.
4. The display case of claim 1, wherein the lamp comprises an HID lamp.
5. The display case of claim 1, wherein the extractor of light is arranged to preferentially remove light along the length of the side-light emitting portion in a plurality of radial directions along said longitudinal axis.
6. The display case of claim 1, wherein the container contains a structural member parallel to orthogonal plane of the view port to block the view of the luminaire inside the case to persons viewing the contents of the case along a plane intersecting the full side-light emitting portion and being orthogonal to the view port.
7. The display case of claim 1, wherein peak illuminance on the first and second target areas lying in a plane within the case, parallel to the view ports, is at least 50 percent greater than peak illuminance on a non-target area lying between the target areas in said plane.
8. The display case of claim 1, wherein:
- a) the light-extraction regions are spatially divided in segments along the length with gaps between the segments; the longitudinal dimension of the gaps being greater than the radial width of their respective light-extraction region;
- b) the majority of said segments are divided with gaps of at least 20 percent of the longitudinal dimension of neighboring segment along the length of the light-extraction regions; and
- c) the majority of said segments have gap portion of the adjacent light-extraction region aligned with at least 20 percent longitudinal dimension of the respective segment along the length of the light-extraction regions.
9. The display case of claim 1, further comprising a transparent cover over the majority of the length of the side-light emitting portion of the luminaire.
10. The display case of claim 9, wherein the transparent cover comprises a diffuser for reducing glare from the luminaire.
11. The display case of claim 9, wherein the transparent cover comprises a Fresnel for directing light emitted from the foregoing portion into a more narrowed beam.
12. A lighted display case with remote light source, comprising:
- a) a container having a view port intended to allow persons outside the container to view contents displayed in the interior of the container;
- b) a solid fiber optic luminaire at least partially mounted within the container; the luminaire having an elongated side-light emitting portion for emitting light from the side of the luminaire onto contents in an interior of the display case; the side-light emitting portion comprising an extractor of light arranged to preferentially extract light from the luminaire and direct said light in at least one radial direction along the length of the side-light emitting portion to at least one target area of said contents along a longitudinal axis of the side-light emitting portion;
- c) the extractor of light comprising first and second light-extraction regions;
- d) a light-delivery system for providing light to the fiber optic luminaire; the light-delivery system having a light source mounted remotely from the container; and
- e) the side-light emitting portion of the luminaire is rotatable about its own longitudinal axis for directing the aim of light emitted therefrom to various radial directions about said axis.
13. The display case of claim 12, wherein:
- a) the view port has a maximum dimension; and
- b) the side-light emitting portion of the luminaire extends across the majority of said maximum dimension.
14. The display case of claim 12, wherein the container contains a structural member parallel to orthogonal plane of the view port to block the view of the luminaire inside the case to persons viewing the contents of the case along a plane intersecting the full side-light emitting portion and being orthogonal to the view port.
15. The display case of claim 12, wherein the case comprising means for releasably holding the luminaire in any of a plurality of predetermined positions.
16. The display case of claim 14, wherein the means for releasably holding comprises a resiliently biased detent mechanism causing said side-light emitting portion to be releasably held in any of a plurality of predetermined radial positions.
17. The display case of claim 12, wherein the lamp comprises an HID lamp.
18. The display case of claim 16, wherein the light-delivery system includes at least one LED and a non-imaging optic for coupling light into a fiber optic structure that passes through a wall of the container.
19. The display case of claim 12, further comprising a transparent cover over the majority of the length of the side-light emitting portion of the luminaire.
20. The display case of claim 19, wherein the transparent cover comprises a diffuser for reducing glare from the luminaire.
21. The display case of claim 19, wherein the transparent cover comprises a Fresnel for directing light emitted from the foregoing portion into a more narrowed beam.
22. A lighted display case with remote light source, comprising:
- a) a container having contents for display;
- b) a first and second solid fiber optic luminaires at least partially mounted within the container; each luminaire having an elongated side-light emitting portion for emitting light from the side of the luminaire onto contents in an interior of the display case; the side-light emitting portion comprising an extractor of light arranged to preferentially extract light from the luminaire and direct said light in at least one radial direction along the length of the side-light emitting portion to at least one target area of said contents along a longitudinal axis of the side-light emitting portion;
- c) the extractor of light comprising first and second light-extraction regions;
- d) the container having a first and second view ports intended to allow persons outside the container to view contents displayed in the interior of the container; the first view port being on one lateral side of the sidelight emitting portion and the second view port being on a second lateral side of said portion;
- e) a light-delivery system having a lamp for supplying light to the first and second luminaires;
- f) the side-light emitting portions of the first and second luminaires being mounted parallel to each other and being respectively positioned to illuminate a target area on one side of the luminaires and a laterally adjacent target area on another side of the luminaires.
23. The display case of claim 22 wherein:
- a) the view port has a maximum dimension; and
- b) the side-light emitting portion of the luminaire extends across the majority of said maximum dimension.
24. The display case of claim 22, wherein the lamp comprises an HID lamp.
25. The display case of claim 22, wherein the container contains a structural member parallel to orthogonal plane of the view port to block the view of the luminaire inside the case to persons viewing the contents of the case along a plane intersecting the full side-light emitting portion and being orthogonal to the view port.
26. The display case of claim 22, further comprising a transparent cover over the majority of the length of the side-light emitting portion of the luminaire.
27. The display case of claim 27, wherein the transparent cover comprises a diffuser for reducing glare from the luminaire.
28. The display case of claim 27, wherein the transparent cover comprises a Fresnel for directing light emitted from the foregoing portion into a more narrowed beam.
29. The display case of claim 22, wherein the light-delivery system includes:
- a) a collector mounted to the container for coupling light along a first optical axis that is angled more than 70 degrees from a main optical axis of the first luminaire; and
- b) a corner-turning device at both ends of the coupler for turning the light from the first and the second optical axis to the said main axis of both said luminaires.
30. The display case of claim 25, wherein the collector comprises a non-imaging collector for reducing the angular distribution of light collected from the HID lamp by the foregoing collector.
31. The display case of claim 25, wherein the light-delivery system includes a first fiber optic structure sufficiently curved to receive light along the first optical axis and to transmit light along the main optical axis of the first luminaire that is more than 70 degrees angled from the first optical axis.
32. The display case of claim 25, wherein the light-delivery system further comprises
- a) a second non-imaging collector for reducing the angular distribution of light collected by the foregoing collector; and
- b) a second fiber optic structure sufficiently curved to receive light from second collector along a respective main second optical axis and to transmit light along the main optical axis of the second luminaire that is more than 70 degrees angled from the second optical axis.
Type: Application
Filed: Apr 24, 2006
Publication Date: Oct 25, 2007
Inventors: Roger Buelow (Gates Mills, OH), John Davenport (Middleburg Heights, OH), William Cassarly (Wooster, OH), Thomas Davenport (Tucson, AZ), Gregory Frankiewicz (Mayfield Heights, OH), Chris Jenson (Twinsburg, OH), Robert Caywood (Vermillion, OH)
Application Number: 11/379,999
International Classification: A47F 11/10 (20060101);