GB2211012A

GB2211012A - Edge-illuminated display aid

Info

Publication number: GB2211012A
Application number: GB8823714A
Authority: GB
Inventors: Desmond Pilkington
Original assignee: Individual
Current assignee: Individual
Priority date: 1987-10-09
Filing date: 1988-10-10
Publication date: 1989-06-21
Also published as: IE872698L; GB8823714D0

Abstract

An illuminated display aid of slim or shallow construction eliminates the space requirement of the customary light-box by employing a lateral light source (10), 62 which shines into an edge (2), 69 of a display element (1), 63 of transparent material, the light after internal reflection being scattered through a main face (3), 72 to back-light a translucent item 67 for display purposes. Uniformity of back-lighting is achieved by a surface treatment (eg abrasion) of at least one main face of the display element to produce the scattering, which treatment is intentionally increased in severity or optical density with increasing distance from the light source (10), 62. The display aid can be employed to present illuminated panels of many shapes and sizes, for displaying thereon photographic transparencies or displaying thereover translucent tubular garments such as stockings and tights. The aid may also be used to illuminate drawing boards and road signs. The display element may be made of opal acrylic and the surface treatment may be stepped, stepless, moulded or painted with spots instead of being abraded. UV light may be employed as an alternative to tungsten filament, halogen or gas discharge lamps. <IMAGE>

Description

"Illuminated Display Aid" This invention relates to an illuminated display aid. It relates in particular to a display device for providing an illuminated backing for translucent goods such as advertisements, photographic transparencies and certain textiles. In a first aspect, the invention relates to a display device for providing uniform rear lighting for a translucent panel. In a second aspect, the invention relates to a display device for the internal illumination of tubular garments, such as stockings, tights, pantie hose and the like. Other aspects of the invention will readily occur to a person skilled in the art of illuminated display.

Illuminated display panels of many shapes and sizes are known, comprising a translucent front or display element bearing the legend, indicia or graphic element to be displayed, and a light-box in the rear. Because of the dimensions of conventional light sources, and the need to locate them so as to illuminate the whole of the display element as uniformly as possible, the light box tends to be a bulky affair, and the complete display panel tends to have a substantial depth or thickness.

It is also well known to display a single stocking or one leg of a pair of tights by stretching it over a moulded dummy leg and foot, which may be solid or hollow, transparent or opaque, but is typically of transparent plastics material and hollow. It is also known to stretch the garment over a flat cutout of wood or plastics having the outline of a leg and foot in silhouette. When an illuminated display is desired, an external spotlight is commonly employed, or the display shares a common source of light with the other articles in a display window or on a sales counter. The visual effect is rather dull.

If a garment is stretched over a hollow transparent or translucent support and an attempt is made to illuminate the garment from within, for display purposes, as by placing a light source or sources in the cavity of the support, the effect produced is to attract attention to the light source rather than the garment, owing to the inevitable falling-off of luminosity with distance from the source, so that the shape, outline and pattern of the garment suffer from blurring, truncation and distortion.

Such measures have little utility and have not found any widespread acceptance.

It is an object of the invention to overcome the above recited disadvantages of current practice in the display of translucent goods. A particular object is to provide an illuminated display panel which does not need to incorporate a bulky light box. Another object of the invention is to provide a display aid for a textile or garment wherein the displayed part thereof is uniformly illuminated. A further object is to create a form of illumination which originates, or gives the appearance of originating, behind or within the displayed fabric, whereby the fabric itself appears luminous, so that details of weave, pattern etc are strikingly emphasized by reason of their differential apparent luminosity.

The invention accordingly provides an illuminated display aid which includes a concealed source of radiation and a display body of a material intrinsically transparent to the radiation, the display body having at least one main display face disposed substantially in a plane and a minor face which is transparent and oriented substantially perpendicularly to said main face, means for directing radiation from said source at said minor face so that it enters the display body, means for assembling the aboverecited elements in an operative relationship, and means for supporting the assembly thereof in a desired location for display, wherein the or each main display face is adapted to emit a visible glow or radiance in response to said radiation whenever incident on the inner surface thereof, in such manner that the response emission intensifies progressively with distance from the radiation source, and that the perceived intensity of the glow or radiance at a given point on the display face is substantially independent of the distance of that point from said radiation source. Preferably the intensification is continuous or stepless so that the perceived intensity is uniform over substantially all of said main display face.

The concealed source of radiation may be, for example, a source of ultraviolet radiation or of visible light which may be white or coloured. When ultraviolet radiation is involved, the material of the display body must of course be one that is transparent to radiation of the relevant frequencies, such as commercially available optical UV-transmitting glass. In the case of visible light, the material may be, for example, glass or transparent plastics material, such as the well-kn(owT ma)terial marketed under the trade designation PERSPEX1. For visible light, small spotlights with conventional tungsten filaments, halogen lamps, gas discharge lamps or other known sources may be used.

The manner of adapting the main display face so that the response emission intensifies progressively includes several useful possibilities. For example, surface irregularities may be moulded into said face during manufacture, as with frosted glass, provided the size of the individual irregularities increases, or their density of distribution increases, or the complexity of their arrangement as a pattern increases, with increasing distance from the intended location of the source of radiation.

As another example, the main display face (starting as a flat or transparent or optical face) may be subjected to surface abrasion of graduated severity which increases with distance from the intended location of the source of radiation (as by grinding with an abrasive powder or paper, by sandblasting or the like).

As another example, the main display face may be treated by chemical etching in a bath from which said face is withdrawn at a controlled uniform speed, the region closest to the intended location of the source of radiation being the first to be withdrawn (and rinsed free of etching composition).

As a further example, the main display face may be spraycoated with a graduated array of tiny spots of paint, ink or the like having a density of distribution which is a minimum adjacent the intended location of the source of radiation, and increases with distance from said source, the coating of spots having the effect of scattering the light which strikes the spots. This variant is probably of most use in conjunction with the use of ultraviolet radiation, where the paint is a UV-fluorescent paint and the effect is fluorescence rather than simple scattering.

In all embodiments wherein visible light is used, the main mechanism of emission is thought to be scattering of light, in that the surface irregularities, or the sprayed-on spots, as the case may be, are of average dimensions which exceed the average wavelength of the light involved. But the invention is not to be understood as limited by any theory as to how it works.

A particular and preferred embodiment of the invention is intended for the back-illumination of translucent display objects, such as photographic transparencies. It demands no specialized shape or size for the display body, which is typically a parallel-faced sheet of Perspex or the like, of rectangular outline, wherein at least one edge face of the rectangle constitutes the minor face through which the radiation is directed. Two opposite edge faces of said rectangle may likewise constitute the minor "face". The locus of maximum distance from the source (in this case sources) of radiation is a straight line in the plane of the rectangle parallel to and equidistant from said opposite edge faces.The manner of adapting the main display face must be correspondingly modified, so that the response emission intensifies progressively from each of said edge faces to reach a maximum along said straight line.

The progression of response emission intensity may be continuous or discontinuous. For example, a discontinuous progression may comprise discrete steps to produce uniform illumination of a series of ranks of items being displayed, such as several parallel rows of photographic transparencies of uniform size, in a field or background of lesser luminosity.

In another embodiment of the invention, intended mainly for the display of stockings, tights and the like, the display body is a parallel-faced sheet of the above-recited material (such as Perspex), shaped to a leg-and-foot silhouette, the main display face thereof comprises one or both faces of the sheet, and the minor face (through which the radiation is directed) is the edge which defines the cut-off end of the leg remote from the foot. In a variant of this embodiment, the main display face comprises one face only of the sheet, the opposite face being covered by a reflecting element, such as a sheet of white paper, to enhance the emitting intensity from the main display face.

The invention will be appreciated in greater detail from the following description of a particular and preferred embodiment thereof, given by way of non-limiting example only, with reference to the accompanying drawings, in which Fig 1 is a front elevation of an illuminated display device for a stocking; Fig 2 is a side elevation of the device of Fig 1; Fig 3 is an enlarged detail from the upper part of Fig 2; Fig 4 is a section taken along the line IV-IV in Fig 1, viewed in the direction of the associated arrows, on an enlarged scale and with additional detail; Fig 5 is a section taken along the line V-V in Fig 2, viewed in the direction of the associated arrows, on an enlarged scale and with additional detail; Fig 6 is a front elevation, partly cut away, of a display device for text or graphic matter, intended for mounting on a surface, such as a wall of a building or vehicles;; and Fig 7 is an enlarged detail of the device of Fig 6, taken in section along the line VII-VII in that figure, and viewed in the direction of the associated arrows.

Referring now to the drawings, and in particular to Figs 6 and 7, a display device for text or graphic matter comprises a baseplate 60, an outer frame 61, two fluorescent strip lamps 62a and b, a display body 63, a diffusing sheet 64, a sub-frame 65 and a transparent cover sheet 66. The device is designed to accommodate a display sheet 67 of or including translucent material intended for display, such as photographic transparencies. Constructional details such as retaining clips, mounting brackets and electrical wiring have been omitted for simplicity.

The base plate 60 supports all the other components, and has a light-reflecting inner or hidden surface 68. The display body 63 is a transparent 1 cm thick parallel-faced rectangular sheet of acrylic plastics material with its two opposing edge faces 69 polished, and its lower face 70 (Fig 7) treated in accordance with the invention by sandblasting. This treatment begins imperceptibly adjacent the strip lamps 62a, 62b and progresses to a line 71 of maximum intensity.

Where the treated surface is coarse in texture, to the extent that its detail is discernible through the transparent or translucent display sheet 67, the coarseness can be masked by placing a diffusing sheet between the display body and the display medium.

Where such a diffusing sheet is used it is preferable to carry out the graduated surface treatment on the face of the display body remote from the face against which the diffusing sheet is placed.

Accordingly the diffusing sheet 64 is of thin opal acrylic plastics material, as commonly used in back-lit advertising and road traffic signs. The sub-frame 65 abuts the assembly of display body 63 and diffusing sheet 64, and encloses and supports the transparent cover sheet 66, whose function is to protect the display sheet 67 from external hazards.

In use of the display device, light from the strip lamps 62a, 62b enters the display body 63 through its edge faces 69 and reaches the specially treated lower or hidden face 70 either directly or by internal reflection, which may be multiple. The light, modified by the surface treatment of the face 70, exits the display body 63 through its upper face 72, passes through the diffusing sheet 64, the display sheet 67 and the cover sheet 66 from outside which the intended effect can be appreciated by a viewer.

Embodiments such as that of Figs 6 and 7 can be used to provide illuminated panels for wall mounting and for the sides of vehicles, eg public service vehicles. They are particularly useful when the available space is too shallow to accommodate a conventional back-lit sign with light-box.

Such embodiments can provide a means for examining X-ray transparencies or other photographic transparencies, in the form of a panel which can be placed on a bench or mounted on a wall for use. They can be employed with advantage wherever there is a need for advertising or display but insufficient space for a conventional light box. Other possible application are to illuminated drawing boards and illuminated road signs.

The display sheet 67 may of course have any desired layout.

Thus it may be largely opaque but with spaced-apart "windows" each back-lighting a respective display item such as a photographic transparency.

The image to be displayed may be printed directly onto the display sheet 67 or onto the diffusing sheet 64.

The graduated treatment by paint or ink spots and the printed image to be displayed may be combined on one face of the display body 63. In this case the density of distribution of the spots is graduated not only to su-it the distance from the source of light but also varied to suit the intensity of emission required to form the desired image. This printing should preferably be applied to the face of the display body remote from the viewer. The reflective backing sheet 68 may be printed with the image required in a conventional manner so that the whole assembly when viewed in, say, daylight will display the image effectively. The graduated printed image on the display body and the printed image on the backing sheet are designed to coincide.

Referring now to Figs 1 - 5 of the drawings, a display body is a 6 mm thick sheet 1 of Perspex, cut out as an approximately life-size silhouette of a foot and leg, to accommodate a lady's stocking stretched neatly over it for purposes of display in a shop window. Its upper edge 2 is straight, planar and polished for good light transmission.

The sheet 1 has a display face 3 and a hidden face 4, the latter covered by an applied sheet 5 of white paper to provide reflectance.

The Perspex sheet 1 is securely held at its upper end between opaque cover sheets 6 by clamp means (not shown) mounted on a backboard 7 (Fig 4) and concealed from view by means of a decorative shield 8 indicated only in broken outline, and also supported by the backboard 7. A lampbox 9 houses two tungsten-filament electric lamps 10 with their reflectors 11, and is likewise mounted on the backboard 7.

The lamps 10 are fitted with electric current supply means and switchgear in conventional manner.

A pair of flat surface-silvered mirrors 12 is also mounted on the backboard 7 in an extension 13 of the lampbox 9, two walls of which extension carry channel sections 14 for the reception of the mirrors 12. The lower edges 15 of the mirrors 12 are aligned with and embrace the upper edge 2 of the Perspex sheet 1, and the mirrors themselves are inclined upwardly and outwardly away from the plane of the sheet 1 at small angles of about 8 , while their upper edges 16 embrace the lamp reflectors 11.

The entire assembly can be mounted for display on a shop window bracket or scaffolding element 17 which includes a steel tube support member 18, by means of a G-clamp 19 with a projecting sleeve socket 20 equipped with a transversely disposed locking screw 21 having a manually operated knob 22. A peg 23 mounted on the lampbox 9 is a rotating fit in the socket 20, and the aforesaid assembly may be rotated about the peg axis to adjust the orientation of the Perspex sheet 1 prior to locking the peg 23 with the aid of the knob 22.

In use of the display device, as best seen from Fig 3, light from the lamps 10 proceeds by back-and-forth reflection of rays 24 between the mirrors 12 to enter the Perspex sheet 1 through the upper edge 2 thereof, and continues by repeated reflection between the faces of the sheet 1 with a certain loss by outward scattering (25) at each incidence on the display face 3 due to the surface irregularities or other surface treatment referred to above. The proportion of light lost by outward scattering increases in the direction of the foot piece 26, to compensate for the ordinary attenuation of the transmitted light with distance from its source, as well as for absorption by the Perspex medium and by the reflecting sheet 5. This is effected by virtue of the graduated treatment of the surface of the display face 3 as previously described. The result, when the device is constructed with proper regard for the principle of the invention as described, is a uniform luminosity of the Perspex sheet 1 and a visually arresting display of the stocking stretched thereover.

Claims

1. An illuminated display aid including a concealed source of radiation (10, 62) and a display body (1, 63) of a material intrinsically transparent to the radiation, the display body having at least one main display face (3, 72) disposed substantially in a plane and a minor face (2, 69) which is transparent and oriented substantially perpendicularly to said main face, means for directing radiation from said source at said minor face so that it enters the display body, means for assembling the above-recited elements in an operative relationship, and means for supporting the assembly thereof in a desired location for display, wherein the or each main display face (3, 72) is adapted to emit a visible glow or radiance in response to said radiation whenever incident on the inner surface thereof, in such manner that the response emission intensifies progressively with distance from the radiation source, and that the perceived intensity of the glow or radiance at a given point on the display face is subs can tially independent of the distance of that point from said radiation source.

2. A display aid according to claim 1, characterized in that the intensification is continuous or stepless so that the perceived emission intensity is uniform over substantially all of said main display face.

3. A display aid according to claim 2, characterized in that the intensification progresses in discrete steps, to produce parallel bands of equal perceived emission intensity, separated by untreated parallel bands of a consequently contrasting appearance.

4. A display aid according to any of claims 1 to 3, characterized in that the main display face (3, 72) is adapted by subjecting it to surface abrasion of graduated severity which increases with distance from the intended location of the source of radiation (10, 62).

5. A display aid according to any of claims 1 to 3, wherein the main display face (3, 72) is adapted by moulding surface irregularities thereinto during manufacture; characterized in that the individual or the statistical properties of the irregularities undergo progressive change with increasing distance from the intended location of the source of radiation (10, 62).

6. A display aid according to any of claims 1 to 3, characterized in that the main display face (3, 72) is adapted by applying tiny spots of paint or the like to the main display face, so that the density of distribution of said spots increases with distance from the light source (10, 62).

7. A display aid according to any of claims 1 to 6, characterized in that the display body is a parallel-faced sheet (63) of acrylic plastics or the like, of rectangular outline, wherein at least one edge face (69) of the rectangle constitutes the minor face through which radiation can be directed.

8. A display aid according to claim 7, characterized in that the minor face (69) comprises two opposed edge faces (69) of the rectangle, each having located near it a respective light source (62a, 62b), and the treatment adapting the main display face (63) increases in severity from a minimum near said edge faces to a maximum along a line (71) substantially equidistant from the light sources (62a, 62b).

9, An illuminated display aid substantially as herein described with reference to or as illustrated in figs 1 to 5, or in figs 6 and 7, of the accompanying drawings.