WO2007127568A2

WO2007127568A2 - Lighted display case with remote light source

Info

Publication number: WO2007127568A2
Application number: PCT/US2007/065053
Authority: WO
Inventors: Roger F. Ii Buelow; John M. Davenport; Gregory P. Frankiewicz; Chris H. Jenson; Robert H. Caywood
Original assignee: Fiberstars, Inc.
Priority date: 2006-04-24
Filing date: 2007-03-27
Publication date: 2007-11-08
Also published as: EP2012617A2; WO2007127568A3; US20070247835A1

Abstract

Lighted refrigerated display case with remote light source comprises a closed container with an interior of the container refrigerated to a temperature below 7 C. The container is thermally insulated from ambient, having internal and external walls. A solid fiber optic lυminaire is at least partially mounted within the container, having an elongated side-light emitting portion for emitting light from the side of the lumiπaire 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. A light-delivery system provides light to the fiber optic luminaire. having a light source mounted remotely from the interior of the container.

Description

LIGHTED DISPLAY CASE WITH REMOTE LIGHT SOURCE

This application claims priority from US Patent Application No. 11/379.999 filed, on April 24_; 2006.

Field of the invention

The present invention relates to a lighted refrigerated 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 lumiπaire.

Background of the invention

Traditional refrigerated display cases used in grocery stores for displaying food products employ fluorescent lamps for interna! illumination. Refrigerated cases may be cold cooled to below about 7 C for non-frozen foods, and below about - 7 C for frozen foods. Refrigerated cases typically include doors with view ports for viewing food products in the cases. Fluorescent lamps typically may illuminate food products in the interna! of the cases with an acceptable leve! of illumination. Fluorescent lamps in elongated, tube form are typically used. This is because traditionally there has been no other Sight source available that would produce enough light over a large enough area so as to illuminate the food products over the entire dimension of a view port of a door. However, using fluorescent tubes in the lowered temperatures mentioned above poses several problems. First, the fluorescent tubes suffer from significant decreases in luminous efficiency (50% or more} at typical lowered temperatures within refrigerated cases. In some situations, special means must be provided to enable fluorescent tubes to even operate, such as driving them with additional power to warm them up in the refrigerated case. Sometimes, the fluorescent tube is sealed partially or completely in a thermal compartment to help trap heat from the tube to prevent the tube from getting too cold.

Despite the foregoing efforts to mitigate significant difficulties in operating fluorescent tubes in refrigerated cases, serious problems still remain. The thermal compartments (or covers) housing the tubes are often dislodged, broken or lost during maintenance, with the result that the iight output drops significantly. Even when the covers are properly maintained, the tubes do not operate at the optimal temperatures required for efficient operation. When a lamp fails, a specialist must be called in to replace the lamp if the thermal compartments or covers are to be properly maintained. This process is expensive and time-consuming and can result in a significant period of time during which a section of a refrigerated display case and its product contents remain unsighted. Another reason a specialist is needed is due to the proximity of the food to the fluorescent tube, which is made of fragile glass and would release hazardous materials if broken during lamp replacement. Such an event would require discarding ai! food products contaminated by the broken lamp

Another common problem with fluorescent lamps is failure of lamp ballasts. The baϋasts are usually located within a door frame, and for this reason the door would be removed from the frame to replace the failed ballast This is another costly operation which must be performed by a specialist to ensure the proper reinstaSlation and operation of the door.

Yet another significant problem with fluorescent lamps in refrigerated display cases is that the heat generated by the lamps work counter to the compressor systems which attempt to keep the food contents cold. The thermodynamic principles of refrigeration dictate that it takes approximately 3 Watts of continuous power to remove 1 Watt of ongoing heating introduced into the cooled internal of a refrigerated display case. Thus, the overaii electrical load of the fluorescent lighting system is multiplied approximate^ threefold when operating inside a refrigerated display case.

Accordingly, it would be desirable to provide a Sight source for illuminating the contents of a refrigerated display case which is easy to maintain, which does not require a specialist, and which does not deliver excess heat into the cooled interna! of the dispiay case.

Brief Summary of the Invention

The disclosed invention provides these benefits and others such as requiring less electrical power to provide comparable amounts of iight even apart from the energy savings obtained by keeping the heat out of the freezer or refrigerator. in accordance with one form of invention, a Sighted refrigerated display case with remote light source is presented which comprises a closed container, an interior of the container being refrigerated to a temperature below 7 C. The container is thermally insulated from an ambient, and has internal and external walls, A solid fiber optic luminaire is at least partiaiiy mounted within the container. The luminaire has an elongated side-light emitting portion for emitting light from the side of the iuminaire onto contents in an interior of the display case. The side-Sight emitting portion comprises an extractor of light arranged to preferentially extract light from the luminaire and direct the light in at least one radiai direction aiong the length of the side-light emitting portion to at least one target area of said contents aiong a longitudinal axis of the side-light emitting portion. A lϊght-deiivery system provides light to the fiber optic luminaire, and has a iight source mounted remotely from the interior of the container.

The foregoing refrigerated display case uses an efficient remote iight source for illuminating contents of the case, it requires only about half or less of the power of a typical fluorescent system to iight a typical refrigerated display case. Because the illuminator is remotely located, the heat from the lamp and ballast is not introduced into the cold environment of the refrigerated display case, thereby reducing the cooling load and attendant cooling costs. Additionally, the remotely located ballast and light source permits easy servicing without the need to employ a specialist or risk contaminating the product with hazardous materials.

Brief Description of the Drawings in the drawings, like reference numerals refer to like parts.

FIG. 1 is a perspective view of a lighted display case, shown partiaiiy cutaway. FIGS. 2 and 3 are simplified front views of the display case of F!G. 1 in reduced size.

FIG, 4 is a block diagram of refrigeration means for the interior of the display case of FiG. 1.

FIG. 5A is a front view of a pair of fiber optic iuminaires and associated parts shown apart from the display case of FIG. 1.

FiG, 5B is a detail, sectional view taken at Arrows 5B-5B in FΪG, 5A. FiG, 5C is an exploded view of the structures shown in FiG, 5A.

FiG. 5D is an exploded view similar to FfG. 5C but showing a single fiber optic lυminaire and associated parts shown separate from the display case of FiG. 1.

FiG. 6 is a sectional view taken at Arrows 6-6 in FlG, 5A. FiG. 7 is a vertical cross section of a feed-through and associated structure of

FIG. 5A.

FiGS. 8A and 8B are cross sections of different types of luminatres.

FiG. 9 is a vertical cross section of a feed-through and associated structure that is alternative to that shown in FIG. 7. FiG, 10 is a perspective view a preferred arrangement for joining fiber optic structures to luminaires, taken at the upper end of a iuminaire,

FIG. 11 shows a cross section of a pair of luminaires, together with a transparent cover for the iuminaϊres.

FiG. 12 is a cross section similar to FIG. 11 but showing a different type of transparent cover for the luminaires.

FiG. 13 is a detaii view of a modified Iuminaire and associated structure taken at Arrows 13-13 in Fig. 1.

FiG. 14A is a side view of a Iuminaire,

FiG, 14B is sectionai view of a iuminaire such as shown in FIG. 14A FiGS. 14C and 14D are cross sectional views of iuminaires.

FiGS. 14E ~ 14G are side views of luminaires.

FiGS. 15A - 15B are simplified views of view ports of the display case of FIG. 1 and associated luminaires.

FiG. 18 is a detail view of a Iuminaire and associated structure taken at Arrows 13-13 in Fig. 1.

FiG. 17 is a detail view, partially in section, of a light-delivery system that may repiace the feed-through and associated light-delivery structures shown in FIG, 1 FiG, 18 is a detail view, partially in section, of another light-delivery system that may replace the feed-through and associated light-delivery structures shown in FiG. 1.

FIG. 19 is a simplified detail view, partially in section, of another light-delivery system that may replace the feed-through and associated light-delivery structures shown in FIG, 1.

FIG, 20 is a simplified detail view, partially in section and partially in block diagram form, of another iight-deiivery system that may replace the feed-through and associated light-delivery structures shown in FfG. 1

FIG. 21 is a simplified detail view in block diagram form of another light-delivery system that may replace the feed-through and associated light-delivery structures shown in FIG, 1.

FiG, 22 is a simplified detail view of another light-delivery system that may replace the feed-through and associated light-delivery structures shown in FiG. 1.

FiG. 23 is similar to FtG, 22, showing a variation of that figure. FiG. 24 is a simplified detail view_: partially in cross section and partially in block diagram form, of another light-delivery system that may replace the feed-through and associated light-delivery structures shown in FfG. 1.

FIG. 25 is similar to FfG. 24, showing a variation of that figure.

Detailed Description of the Invention

FIG. 1 shows a display case 10 for Illuminating contents of the case, such as contents 14, 16 and 18. Case 10 includes a closed container 1 1 and fiber optic iuminaires (not shown) behind structural members 12a - 12d for achieving the foregoing purpose of illumination. The term "fiber optic" Suminaire is intended to cover an acrylic rod luminaire that receives light directly from a light source as well as indirectly through a fiber optic cable or other structure. Preferably, case 10 includes doors 19, 20 and 21 having respective view ports 19a, 20a and 21a, These view ports preferably comprises transparent windows, as shown, but could comprise a doorway when doors 19, 20 or 21 are opened for viewing contents of the display case. The iuminatres extend vertically over dimension 17a, whereas the maximum dimension of a view port (e.g , 19a) is dimension 17b. As can be seen dimension 17a is at least the majority of dimension 17b. Rather than including windows 19a_; 20a and 21a on doors, display case 10a of FIG. 2 shows doors 19, 20 and 21 Sacking windows, and FJG. 3 shows display case 10b Sacking doors and instead having openings 25a, 25b and 25c allowing access to contents. As shown in FIG, 1 , an illuminator 24 is preferably mounted atop container 11, with flexible fiber optic cables 26 leading to the luminaires (not shown). A facade 27, shown in phantom, may shield illuminator 24 and fiber optic cabies 26 from view.

Referring to FIG. 4, interior 23 of display case 10 (FlG. 1) is preferably refrigerated to below about 7 C for unfrozen refrigeration of contents, and below about - 7 C for frozen refrigeration of contents. This may be accomplished by conventional refrigeration means 22 for cooling interior 23 of display case 10 of FΪG. 1.

FfGS. SA, 5B₁ 5C and 6 show fiber optic iuminaires 30 and 32, Referring to FiG. 1, such a pair of luminaires may be contained between doors 19 and 20, or between doors 20 and 21. As shown in FtG, 5A_: left-hand luminaire 30 illuminates a target area (not shown) to the left of the iuminaire, and right-hand luminaire 32 illuminates a target area (not shown) to the right of luminaire 32 As shown in FiGS. 5C and 6, each iυrninaϊre may be provided with respective reflectors 34 and 36, Such reflectors may be diffuse or specular. Reflectors 34 and 36 may be separate from each other or integral to each other As shown in FfG. 5C, iuminaires 30 and 32 may be held in place with upper clamp 38, middle clamp 40 and lower damp 42. CSamps 38, 40 and 42 maintain desired lateral positions of the associated clamped portions of the luminaires, In addition, iower clamp 42 includes a horizontaliy inclined piate 42a for maintaining the vertical positions of the iuminaires.

As best shown in F!G. 58, the luminaires may be provided with claddings within the clamps, such as clamp 38. In particular, FiG. SB shows a cladding 30b that may surround luminaire 30 within clamp 38: ciadding 30b having a lower refractive index than the core of the luminaire. Similarly, a cladding 32b may surround luminaire 32 within clamp 38; cladding 32b having a lower refractive index than the core of the lurninaire. The luminaires may be provided with similar cladding in their portions held within the other ciamps, such as clamps 40 and 42 shown in FΪG, 5A,

Clamp 44 (FfG. 5A-5C) hoids the lower portions of fiber optic cabies 26a and 26b centered respectively above iuminaires 30 and 32. As best shown in F!G. 5B, damp 44 cooperates with sleeves 48a and 46b for aiigπing the bottom portions of fiber optic cables 2Qa and 26b Sleeves 46a and 48b are preferably made of metal, and additionally serve to prevent kinking of the bottom portions of the fiber optic cables. As shown in FIG, 5B, cable 26a comprises a core 26c_; a cladding 28d of lower refractive index than core 26c and a protective jacket 26e of PVC or vinyl, for instance. Similarly, cable 26b comprises a core 26f, a cladding 2βg of higher refractive index material and a protective jacket 2βh of PVC or vinyl, for instance.

A channel 48 may be conveniently used for mounting the iυminaires in a display case. As shown in FiG. 5C, damps 38, 40, 42 and 44 may be secured to channel 48, by bolts 50a_: which is in turn secured to a structural member 12b or 12c (FSG. 1) by boits 50b. The foregoing damps secure the luminaires and their input fiber optic cables in position. Reflectors 34 and 38 may be secured to channel 48 by bolts 50c, Thus, channel 48 may be conveniently used for mounting the luminaire arrangement within a display case, either as an onginai mounting or a retrofit mounting. As shown in FIG. 5A, feed-throughs 54a and 54b are used for feeding fiber optic cables 2δa and 28b through the ceiling of container 11. in particular, these feed- throughs preferabiy seal cables 28a and 2δb to at least the internal wall 58 of the container, it is preferred that feed-throughs also seal the cables to externa! wall 58 of the container. FiG. 5D shows a single iuminaire 30 and associated structures for use in the

FIG. 1 display case to the left of door 19 or to the right of door 21 — that is, at the leftmost or right-most ends of the display case. Non-specular (diffusive) reflector 35a and 35b may have a different shape from non-specular reflectors 34 and 38 of F5G, 5C, Other than the possible use of a differently shaped reflector and the use of only a single iuminaire, the structures of FSG. 5D are similar to those in FiG. 5C. Of course, singie- iurninaire clamps 38a, 40a and 42b are used in FSG. 5D rather than the double- iuminaire damps 38, 40 and 42 in FIG. 5C. Similarly, a single-cable damp 44a is used in FIG. 5D rather than the doubie-cabie clamp 44 in FiG. 5C.

FiG. 7 shows feed-through 54a for feeding fiexible fiber optic cable 28a through a wall (e.g., ceiling) of container 11. Feed-though 54a comprises a penetrating member 60 having a relatively narrow portion 80a passing through interna! and external wails 56 and 58 (and thermal insulation 62 therebetween). This feed-through further comprises a relatively enlarged portion 60b with an upwardly (or axially) facing channel 60c for holding an G~ring 64 or bead of silicone or other sealant materia!. An externally threaded portion of relatively narrow portion 60a threadedly receives a nut 66 with sufficient tension as to compress Oring 64 and seal enlarged portion 60b against internal wall 56. Meanwhile, a conventional compression fitting 88 is used to seal cable 26a against enlarged portion 60b.

Luminaires 30 and 32 may preferably comprise solid fiber optic structures, such as an acrylic polymer rod. FfG. 8A shows a soiid, single-strand luminatre 70, whereas FlG. 8B shows an alternative single-strand luminaire 72 having a core 72a and lower refractive index cladding 72b such as a fluoropolymer. Although the iuminaires of FIGS, 8A and 88 are shown with circular cross sections, high volume (and hence low cost) molding of Suminaires with other cross sections can be carried out. Other cross sections could impart more directionality out light output to a luminaire than with a circular cross section. FIG, 9 shows a preferred feed-through 78 for feeding through container 11 a fiber optic structure 78. Fiber optic structure 78 may be a glass or quartz rod used to thermally isolate the heat of a iamp (and baϊlast) from the interior of container 11 or from a thermally sensitive luminaire (not shown) that receives light from structure 78, Alternatively, fiber optic structure 78 could be an extension of a luminaire upwardly (in the orientation shown) through the ceiling of container 11 , or a flexible fiber optic cable that feeds light to a luminaire {not shown) in the interior of the container.

Feed-through 78 comprises a central cylindrical penetrating part 79 enshβathing fiber optic structure 78, upper and lower compression fittings 80 and 82, and O-rings 81 and 83. Compression fitting 80 inciudes a threaded nut 80a pressing compressible O- ring 81 into sealed relation against externa! 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 8Oa₁ 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 interna! and external waiis 56 and 58 of the container.

FIG. 10 shows a pair of luminaires 30 and 32 that are rotatabie about their respective axes. This aiiows each iuminaire to be rotated as desired for moving the peak illuminance laterally across contents of the display case of FJG, 1. This is especially desirable as the contents to be displayed are moved deeper into the display case or shallower into the case. As the contents are so moved, the location of the peak illuminance can be shifted so as to properly illuminate the contents. Preferably, the luminaires will be releasabSy held in a desired position. Means for accomplishing this would include electro-mechanical means for holding the iuminaire in position, frictiona! means for holding the iuminaire in position, or mechanics! means such as the use of a set screw for holding the Iuminaire in position.

More preferably, luminaires will be releasably heid 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 foliows. In FIG. 10, iuminaire 32 is shown in phantom, and its description will be omitted since it may use the same type of arrangement for being rotated as Suminaire 30. As in FIG, 5A, a ciamp 44 holds the lower end of fiber optic cabie 26a, Cable 26a could be replaced with a glass or quartz rod, for example. Clamp 44 cooperates with sleeve 46a protecting the lower end of the cable. A ciamp 38a, modified from clamp 38 shown in FIG, 5A, has a resiliently biased arm 90 whose lower portion comprises a detent 92, which may be shaped in the form of a semi-sphere, for instance. Detent 92 may be pressed into any of various holes 94 extending outwardly along band 96. In this way, a user can easily grasp the iuminaire and rotate detent 92 into any of holes 94, for instance, which will be held in such hole by resiliently biased arm 90. However, the user can use manual (hand) force to rotate the Iuminaire into another predetermined position, where it will be reSeasabiy held until another manual force again rotates the luminaire. Typically, hoies 94 would be more closely spaced than shown in FIG. 10.

FIG, 11 shows luminaires 30 and 32 together with a transparent cover 100. Transparent cover 100 protects the surface of the luminaires from soiling or injury.

Beneficially, transparent cover 100 may aiso comprise, or be associated with, a lens, such as the Fresne! lens shown. As a Fresnei Sens, transparent cover 100 redirects representative Sight rays 102a and 102b as the rays pass through the Sens, as shown. Such reorientation of the Sight rays permits steering of the peak of light distribution deeper or shallower into the dispiay case as desired. The transparent cover can additionally act as a Sight diffuser to minimize direct views of the luminaire and to soften specular images of the Suminaire that may be seen as reflections in the contents of the dispiay case.

Secondary optics, such as a Fresne! lens, becomes especially valuable when the intensity (iumens/steradian) from a round rod Suminaire is insufficient to achieve a desired target surface illuminance. This typicaily 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 smali (e.g., 10 cm). The Fresnel iens can increase the intensity of the light directed toward the target surface and thereby increase the target surface illuminance. With a round rod Suminaire, the peak intensity occurs when the radial paint stripe width (e.g., the illustrated radial angle 101 for a Sight extractor) is approximately 20 to 30 degrees, so the Fresnel iens is often used with narrow paint stripes.

FiG. 12 shows iuminaires 30 and 32 with respective transparent covers 104a and 104b. Transparent covers 104a and 104b may comprise &n optical lens for making the light distribution from the Suminaires, e.g., rays 106a and 106b_; more sharpiy peaked FiGS. 13-14C concern the use of a singie luminaire to ilSuminate two laterally adjacent target areas, and a problem of light blocking that might occur in such luminaire.

FIG. 13 shows a portion of the display case of FfG. 1 with doors 19 and 20. in a variation from the display case of FIG. 1. only a singie luminaire 119 is mounted on channel 48, which is secured to structural member 12b, The figure also shows luminaire 119 with light-extraction regions 120 and 121 of the side-light emitting portion. Light rays (e.g. 123a and 123b) from light-extraction region 120 illuminate a desired target area 125, while the light rays (e.g. 122a and 122b) illuminate a laterally adjacent desired target area 124,

Using a singie Suminaire as in FIG. 13 requires more lumens of light to be supplied to the iuminaire than to each of the two luminaires shown in FIG. 5A, for instance. Typically, a larger diameter luminaire would be used for the FSG. 13 embodiment. FiG, 14A shows a iuminaire 110a shows with light-extraction regions 111a and 112a, arbitrariiy shown as cross-hatched. FIG- 14B shows a iuminaire generally designated 110, to refer to Iuminaire 110a of FfG, 14A, for instance, FJG. 14B also shows a pair of Sight-extraction regions generally designated as 111 and 112, to refer to regions 111a and 112a in FIG. 14A₁ for instance. The light-extraction regions 111a and 112a are arranged longitudinally aiong the length of the iuminaire 110a As used herein, a single iight-extraction region provides illumination to a single continuous target area along some part of the iength of the iuminaire. Sn accordance with an aspect of the invention, the Sight is extracted from the side-light emitting portion by light- extraction regions 111a and 1 12a to illuminate a pair of respective pair of iateraSly adjacent target areas (not shown), in FiG, 14A, light-extraction regions 111a and 112a are continuous along the length of the iuminaire. The extraction efficiency within a iight-extraction region may be constant within each region or may vary within the region. Spatial variations in extraction efficiency are used to adjust the distribution of light at the target. In many geometries of iight-extraction regions 111a and 112a_; light rays (not shown) from one light-extraction regions are biocked by the other light-extraction region, resulting in re- scattering or absorption of the light rays that would otherwise fall on a desired target area. This blockage problem is shown in FiGS. 14C and 14D in connection with luminaires 126a and 126b. in FIG, 14C, iuminaire 126a has two adjacent iight-extraction regions 127 and 128 arranged in a manner to iliuminate two separate target areas of the contents of the display case. Light-extraction means 127 illuminates a target area to its left, whereas iight-extraction region 128 illuminates a target area to its right. The iight-extraction regions 127 and 128 are spaced from each other around a perimeter of said side-light emitting portion taken orthogonally to mam optica! axis of said side-light emitting portion, in particuiar light-extraction regions 127 and 128 are spaced from each other at an angle of α around the perimeter of the side-light emitting portion Generally, the Sight rays (e.g. 129a and 129b) from the light-extraction region 127 illuminate the desired target area, but a portion of light rays (e.g. 129c) from the iight-extraction means 127 are biocked by the other Sight-extraction region 128. These blocked light rays are re- scattered by the light-extraction means 128 with some absorption. These re- scattered light rays (not shown) add with the light rays (not shown) from the iight-extraction region 128 to illuminate the target area to the right of that region. Typically, the amount of itght rays biockec! depends upon the angular separation α between the iight- extraction regions 127 and 128. As the angle α increases, the amount of blockage of the Sight rays tends to increase. FIG, 14D shows a lumϊnaϊre 126b with a single Sight-extraction region 130, The light-extraction region 130 illuminates a desired target area of the contents of the display case with light rays (e.g. 131a, 131b, and 131c), The light-extraction region formed in the same relative position as Sight-extraction region 127 of FIG. 14C, In the absence of an adjacent light-extraction region, Sight-extraction region 130 illuminates the desired target area with Sight rays (e.g. 131a, 131b, and 131c) without any blockage as in FIG. 14C.

Returning to FlG. 14A, the blocked light rays (not shown) toy the adjacent light- extraction region adds to the illuminance on the respective target area being illuminated by the light-extraction region blocking the light rays. Some of the light rays {not shown) from Sight-extraction region 111a are being blocked by the light-extraction region 112a and some of the light rays (not shown) are being blocked by the light-extraction region 111a, This bSockage probiern can be solved by dividing the light-extraction region 111a and 112a in longitudinal segments along the length of the iuminaire in such a manner such that the blockage is reduced considerably, resuiting in increase of the illuminance on the desired target area.

FIG. 14E shows a iuminaire 110b with light-extraction regions 111b and 112b. To overcome the above-mentioned blockage problem, the Sight-extraction regions are spalialiy divided into segments with gaps between the segments along the length of the Iuminaire 110b. Light-extraction region 111b is spatially divided into segments 113 with a gap 113a between adjacent segments. SimilarSy, light-extraction region 112b is spatiaiSy divided into segments 1 14 with a gap 1 14a between adjacent segments. The longitudinal dimension of gaps 1 13a and 114a is at Seast 20 percent of the length of the neighboring segments 113 and 114 respectively. The segments 113 are aligned in such a manner so that each gap 113a is at least 20 percent of the longitudinal dimension of a segment 114 at the same point along the longitudinal axis of Iuminaire 110b. The longitudinal dimension of gaps 113a and 114a of FIG, 14E and similar gaps discussed in the following figures are preferably greater than the radiai width of their respective light-extraction region along the length of the luminaire. More preferably, the longitudinal dimensions of such gaps are greater than twice the radial width of their respective light-extraction region along the length of the luminaire. Further, the target areas illuminated by the light-extraction regions (e.g., 11Oa₁ 110b, F!G. 14E) are spaced from the iuminaire by at least 5 times the longitudinal dimension of such gaps. This is to assure that the Sight-extraction regions appear as continuous from the viewpoint of the target areas. FiG, 14F shows a iuminaire 110c with Sight-extraction regions 111c and 112c.

The Sight-extraction regions are spatiaily divided into segments 115 and 118. respectively, The segments 115 and 116 have respective gaps 115a and 116a between them, The segments 115 and 116 are arranged in such a manner so that the longitudinal dimension of the gaps 115a and 1 1δa is equivalent to the longitudinal dimension of the adjacent segment of the adjacent light-extraction region

FiG. 14G shows a light iuminaire 110d with light-extraction regions 111d and 112d, The light-extraction regions are spatially divided into segments 117 and 118, respectively. The segments 117 and 118 have gaps 117a and 1 18a between them, respectively. The gaps 117a and 118a are relatively longer than the gaps between the segments in FiGS. 14E and 14F. This kind of spatial division of the light-extraction regions greatly reduces the blockage of the light by the adjacent Sight-extraction region, which results in an increase of illuminance on the desired target area.

The light extractor on a iuminaire 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 FiGS. 15A and 15B.

FiG. 1 SA is a simplified view of view port 19a and associated luminaire of the display case 10 of FiG, 1. A desired target area 135 is illuminated by luminaire 132, The iuminaire receives light from a light source 137, which is extracted by light- extraction region 133 comprising portions133a and 133b, arbitrarily shown cross- hatched. Light-extraction portion 133a of luminaire 132 illuminates a vertically upper portion 135a of target area 135 with a peak illuminance 134a, Light-extraction portion133b illuminates lower portion of target area 135 with a peak illuminance 134b. Target area 135 is vertically continuous. To the right of verticaliy oriented luminaire 132 there are shown a cross section of the iuminaire with light-extraction portion 133a. for describing the upper half of the luminaire, and a crass section of the iuminaire with light-extraction portion 133b describing the lower half of the iuminaire. These cross sections help to more clearly show the reiative radiai positions of light-extraction portions 133a and 133b on the iuminaire. Such radial dispiacement of portion 133b relative to portion 133a results in the shift of peak illuminance 134a to peak illuminance 134b on the target area 135.

FiG. 15B is a simplified view of view ports 20a and 21a of the dispiay case 10 of FIG. 1 and an associated but modified Suminaire, A light source 140 provides light to a luminaire 142. In iuminaire 142, a light-extraction region 142a illuminates a target area 150 at the upper ieft of the iuminaire, having a peak illuminance 148a. A second light- extraction region 142b illuminates a separate target area 152 at the Sower right of the luminaire, having a peak illuminance 148b The single Suminaire of FIG. 15B can illuminate target areas on different lateral sides of the iuminaire. The cross sections of luminaire 142 on either side of the verticaiiy shown iuminaire more clearly show the radial dispiacement of Sight-extraction regions 142a and 142b from each other.

A preferred iight extractor comprises a layer of paint exhibiting Lambertsan 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 Sight in a preferred radial direction from an elongated luminaire. A textured type of extractor could alternatively be used, wherein the surface of the iuminaire 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: US Patent Application S.N. 11/36671 1 filed 2 March 2006 for Luminaire with improved Lateral Illuminance Control by W Cassarly et a!.

US Patent Application S N. 11/108,279 filed 18 April 2005 for Efficient Luminaire with Directional Side-Light Extraction by W. Cassarly et ai. The present joint owners of the foregoing applications and of the present appSicafion are Fiberstars, Inc. and Optical Research Associates. The entireties of the disclosures of the foregoing applications are hereby incorporated by reference,

FIG. 16 shows a portion of the display case of FfG. 1 with doors 19 and 2O₁ and iiiustrates a region of relatively low level light behind structural member 12b. As shown, luminaires 154a and 154b are mounted on channel 48, which is secured to structural member 12b. Light rays {e.g. 160a and 160b) originating from a light-extraction region 156 on luminaire 154b illuminate a desired target area 186. Target areas 166 and 188 lie in a plane parallel to the view port of doors 19 and 20, the view ports being shown in FIG. 1 as 19a and 20a. Light rays (e.g. 162a and 182b) originating from light- extraction region 158 on Suminaire 154a illuminate a desired target area 168. in the arrangement shown, peak illuminance on target areas 166 and 168 is at ieast 50 percent greater than peak illuminance on non-target area 170 lying between the target areas in the same plane.

Various benefits arise because the luminaires in both F!GS. 13 and 16 are blocked from view for a person directly in front of the tuminaire(s). In FIG. 13, a person directly in front of the display case and luminaire 119 would not see lumtnairβ 119 owing to the interposition of structural member 12b and channel 48, By "directiy in front" means a person viewing the luminaire along a plane intersecting the fu!l length of the side-light emitting portion and being orthogonal to the plane of doors 19 and 20. Similarly, in FfG. 16, a person directly in front of the dispiay case and luminaires 154a and 154b would not see the luminaires owing to the interposition of structural member

12b and channel 48. By placing the luminaires out of direct view, a person is not subjected to bright light from the luminaires, providing an aesthetic advantage.

Additionally, the fiber optic iuminaires 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 (FJG. 13} each of which covers a limited angle around the αrcumference of their associated luminaire 113. Either a single Sight-extraction region would be used for directing Sight to a single target area, or both light-extraction regions would be used for directing Sight to two separate target areas as shown in FIG. 13. Compared with a traditional fluorescent lamp, a fiber optic iυminaire of one aspect of the invention wiSI typically provide the same iSiuminance on target area{s} with fewer iumens of iight. Thus, referring to FiG. 16, a fiber optic iuminaire of one aspect of the invention will provide reiativeiy iess Sight to non-target area 170 than wil! a fluorescent iamp.

Further, fiber optic iuminasres of one aspect of the invention may deiiver light to the target area more efficiently than fSuorescent lamps since they can have smaller cross-sectiona! dimension{s) and are thereby less likely to biock Sight which strikes a reflector. For instance, a fiber optic luminasrβ typicalSy wouid be about 19 mm. or preferabiy 15 mm, or iess in diameter (for a round luminaire) compared with 25-37 mm diameter for a typical fluorescent iamp. Because the reflector must often be placed close to th& fluorescent iamp, a substantias amount of iight will restrike the fSuorescent lamp after hitting the reflector. The slimmer luminaire can better accommodate use of reflectors, such as reflectors 34 and 38.

FlG, 17 shows a light-delivery system 180 that may replace the feed-through 76 and associated Sight-delivery structures shown in FfG, 1. Light-delivery system 180 comprises an HID lamp 182 with a coSlector 184 for coliecting light afong a main optica! axis coinciding with the main optica! axis of a luminaire 186. HiD lamp 182 may comprise a mefaS haiide iamp, by way of example. Collector 184 provides light to fiber optic structure 78, which may be embodied in different forms as described above in connection with F(G. 9. Sn the embodiment shown in FJG. 17, fiber optic structure 78 provides light to a separate luminaire 186. Structure 188 is secured by cSarop 38 and the bottom portion of fiber optic staicture 78 is secured by damp 44 and sleeve 46, Feed-through 76 is used in the same manner as in FIG. 9 above.

HID lamp 182 and colϊector 184 are conveniently protected by a housing 190 mounted atop container 11. The housing may include an air intake with dust fiiter (not shown) and a hot air exhaust fan (not shown). This arrangement does not leave exposed outside the container any flexible fiber optic cabies that couSd potentially be damaged if bent or kinked, for instance. FiG, 18 shows another Sight-delivery system 194 that may replace the feed- throughs 76 and associated Sight-delivery structures shown in FfG. 1. Light-delivery system 194 comprises an HID lamp 182 and collector 184a, However, collector 184a is configured and positioned to send light directly to a Sight-receiving surface 196a of a lυminaire 198, via a infra-red reflecting window 197. Window 197 may be doubie- paned to further prevent introduction of heat into the interior of container 11. Window

197 may be sealed to external wail 58 of the container by any suitable means, such as adhesive. A similar window 198 may be sealed to internal wall 58 of the container. If desired, a liner 199 may be inserted between windows 198 and 199 to protect insulation 82.

FIG. 19 shows another light-delivery system 200 that may replace the feed- throυghs 76 and associated light-delivery structures shown in FfG, 1 , In system 200, an HiD Samp 202 (e.g., metal halide) provides light that Is collected by non-imaging collectors 204 and 206. Non-imaging collectors 204 and 206 reduce the angular distribution of Sight they collect from HID Samp 202, Thermal-isolating rods 208 and 210. typically made of glass or quartz, receive light from colSectors 204 and 206, respectively. Rods 208 and 210 may be curved as shown to reorient light received by the rods more than 70 degrees, and preferably about 90 degrees as shown. Rods 208 and 210 may be fed downwardly though the upper surface of container 11 in the same manner as fiber optic structure 78 of FfG. 9 extends downwardiy through container 11, Feed- throughs 212a and 212b may be the same as feed-through 78 of F!G> 9. Conveniently, rods 208 anά 210 can supply light to adjacent luminaires which respectively direct light to contents of the container visible through respective view ports (e.g., 19a, 20a, FfG. 1) in laterally adjacent doors of the container. FIG. 20 shows another iight-delivery system 214 that may replace the feed- throughs 76 and associated Sight-deiivery structures shown in FfG. 1. System 214 includes a halogen Samp 216 and a holiow, dichroic-coated non-imaging collector 218, Non-imaging collectors do not require imaging, but can Include Imaging, as further described in William J. Cassarly. ^:'Mon~irnaging Optics: Concentration and Illumination" in the OSA Handbook of Optics, Volume S₁ Chapter 2. Collector 218 couples light onto optical structure 220. Optica! structure 220 may comprise fiber optic structure 78 of FIG. 9, or window 198 of FfG. 18, by way of example. FiG, 21 shows another Sight-delivery system 224 that may replace the feed- throughs 76 and associated light-delivery structures shown in FfG. 1. System 224 includes one or more light-emitting diodes (LEDs) 226, whose light is collected by a non-imaging collector 228, which reduces the angular distribution of iight collected from the one or more LEDs 228. Collector 228 provides light to optical structure 220, as described in connection with FIG. 20 above.

FlG. 22 shows another Sight-delivery system 230 that may replace the feed- throughs 76 and associated iignt-deStvβry structures shown in FfG. 1, System 230 includes a light source 232, such as an HiD lamp and light collector, a fiber optic optica! splitter 234 for apportioning iight into to output arms 234a and 234b from an tnput arm 234c. Sputter 234 couid be formed of glass or quartz if light source 232 emitted too much heat, or couid be formed of the other materials mentioned above for forming fiber optic structures such as the Suminaϊres. Optica! splitter 234 provides iight to luminaires 236a and 236b, which may be located completely within the container, or may extend upwardly through the top of the container, as does fiber optic structure 78 of F!G. 9

FiG. 23 shows another iight-delivβry system 238 similar to that shown in FfG. 22. but showing a variation of system 230 of that figure. In particular, in system 238, the input arm 240c of fiber optic optica! splitter 240 is oriented more than 70 degrees

(preferably about 90 degrees) from the main optica! axis of luminaires 236a and 236b. This arrangement accommodates a different orientation of light source 232.

FiG. 24 shows another Sight-deiivery system 244 that may replace the feed- throughs 76 and associated iight-deSivery structures shown in FfG, 1 System 244 incSudes a pair of fiber optic structures 246 and 248 that coilectiveSy present their input faces 246a and 246b to a light source 232. Each of input faces 246a and 248a preferably have a half-round shape, so as to present a round shape to light source 232. Each of structures 246 and 248 may have S-shapes as shown, before being fed through the top of container 11 with feed-tnraughs 76 as described above in connection with RG. 9. Structures 246 and 24S provide Sight to Suminaires 250 and 252.

FiG. 25 shows another Sight-delivery system 254 similar to that shown in F5G. 24, but showing a variation of system 244 of that figure. In system 254, light source 232 delivers light along a main optic axis that is angied more than 70 degrees (preferably about 90 degrees) from a main optical axis of a iuminaire, which would be vertical for the display case of FtG, 1. A pair of fiber optic structures 256 and 258 present their input faces 256a and 258a to Sight source 232. The lower portions of structures 256 and 258 have been omitted, but such lower portions may conform to the lower portions of structures 246 and 248 of FIG, 24. While the invention has been described with respect to specific embodiments by way of iiiustration, 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-vioiet filters in the described fiber optic iight-deiivery 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

What is claimed is:

1 , A Sighted display case with remote light source, comprising: a) a container having contents for display; b) a solid fiber optic lυminaire at least partially mounted within the container; the iurπinaire 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-Sight emitting portion comprising an extractor of light arranged to preferentialiy extract light from the luminaire and direct said Sight 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 Sight-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 laterai 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 iuminaire; the light- delivery system having a light source mounted remotely from the container; f) the iuminaire being arranged to iiluminate 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 iSluminated by the first and second Sight-extraction regions; and g) the first and second Sight-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 Sighted dispiay case of CSaim 1 , wherein. a) the container is open to its ambient; and b) the interior of the container is maintained within 5C if the temperature of the ambient.

3, The display case of Ciaim 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 Ciaim 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 iying 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 ϋght-extracfion regions are spafiaily 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 iight- extraction regions; and c) the majority of said segments have gap portion of the adjacent light-extraction region aiigned 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 Ciaim 9, wherein the transparent cover comprises a diffuser for reducing glare from the iuminaire.

11. The display case of Claim 9, wherein the transparent cover comprises a Fresnei for directing light emitted from the foregoing portion into a more narrowed beam.

12. A Sighted display case with remote light source, comprising: a) a container having a view port intended to ailow persons outside the container to view contents dispiayed in trie interior of the container; b) a soiid 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 prefereπtiaiiy extract light from the luminaire and direct said Sight in at least one radial direction along the length of the side-iight 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 fight comprising first and second light-extraction regions, d) a light-delivery system for providing light to the fiber optic iuminaire; the light- delivery system having a light source mounted remotely from the container; and e) the side-light emitting portion of the luminaire is rotatabie about its own longitudinal axis for directing the aim of light emitted therefrom to various radial directions about said axis.

13. The dispiay case of Ciaim 12, wherein: a) the view port has a maximum dimension, and b) the side-hght 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 paraiiei to orthogonal plane of the view port to block the view of the iuminaire inside the case to persons viewing the contents of the case along a plane intersecting the fuil side-light emitting portion and being orthogonal to the view port,

15. The display case of Claim 12, wherein the case comprising means for relβasably holding the luminaire in any of a plurality of predetermined positions.

16. The display case of Claim 14, wherein the means for reieasabiy holding composes a resilienily biased detent mechanism causing said side-Sight emitting portion to be rβlβasabiy held in any of a plurality of predetermined radia! positions,

17. The display case of Claim 12, wherein the lamp comprises an HID Samp.

18. The display case of CSaim 16, wherein the iight-delivβry system includes at least one LED and a non-imaging optic for coupling light into a fiber optic structure that passes through a wail 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 giare from the luminaire.

21, The display case of Claim 19. wherein the transparent cover comprises a Fresnei 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 luminairβ 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 preferentiaily extract light from the iuminaire and direct said light in at least one radia! 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 sidelight 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-deSivery system having a lamp for supplying light to the first and second luminaires: f) the side-Sight emitting portions of the first and second iuminaires being mounted parallel to each other and being respectively positioned to illuminate a target area on one side of the Sumiπaires 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-iight emitting portion of the luminaire extends across the majority of said maximum dimension.

24, The dispiay case of Ciaim 22_: wherein the Samp comprises an HID Samp.

25. The display case of Ciaim 22, wherein the container contains a structuraS member paraiie! to orthogonal plane of the view port to block the view of the iuminaire inside the case to persons viewing the contents of the case along a plane intersecting the full side-Sight emitting portion and being orthogonal to the view port

26. The dispiay case of Claim 22, further comprising a transparent cover over the majority of the length of the side-iight emitting portion of the luminaire.

27. The display case of Ciaim 27, wherein the transparent cover comprises a diffuser for reducing glare from the iumϊnairβ.

28. The display case of CSaim 27, wherein the transparent cover comprises a Fresne! for directing light emitted from the foregoing portion into a more narrowed beam.

29. The display case of Claim 22, wherein the iight-delivery system includes; a) a coilector mounted to the container for coupling Sight along a first optical axis that is angled more than 70 degrees from a main optica! axis of the first iuminaire; and b) a corner-turning device at both ends of the coupSer for turning the light from the first and the second optica! axis to the said main axis of both said luminaires.

30. The display case of Claim 25, wherein the collector comprises a non-imaging coliector for reducing the angular distribution of light collected from the HiD lamp by the foregoing col Sector.

31. The display case of Claim 25, wherein the light-delivery system includes a first fiber optic structure sufficiently curved to receive Sight along the first optica! axis and to transmit Sight along the main optica! 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 Sight-delivery system further comprises a) a second non-imaging coliector for reducing the angular distribution of itght collected by the foregoing coiiector; and b) a second fiber optic structure sufficiently curved to receive light from second collector aiong a respective main second optica! 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.