EP0148861A1

EP0148861A1 - An arrangement for a display device which can be acted upon by light and is provided with a display surface

Info

Publication number: EP0148861A1
Application number: EP19840902228
Authority: EP
Inventors: Ulf Henke
Original assignee: Individual
Current assignee: Individual
Priority date: 1983-05-26
Filing date: 1984-05-17
Publication date: 1985-07-24
Also published as: ES532834A0; SE8302959D0; AU2968484A; SE8302959L; FR2546651A1; WO1984004838A1; ES8503156A1

Abstract

Montage pour dispositif d'affichage sur lequel peut agir de la lumière et qui est doté d'une surface d'affichage, et sur lequel peut agir de la lumière le frappant presque parallèlement à ladite surface d'affichage. Grâce à la présente invention, la lumière est répartie de manière efficace sur toute la surface d'affichage du dispositif. Conformément à la présente invention, une plaque (1) ou autre à base de plexiglas ou d'un matériau doté de propriétés similaires de conduction de la lumière, possède une surface arquée (3) sur le côté opposé à ladite surface d'affichage (2) de préférence plane de ladite plaque.Mounting for a display device on which light can act and which has a display surface, and on which light can strike it almost parallel to said display surface. Thanks to the present invention, the light is efficiently distributed over the entire display surface of the device. According to the present invention, a plate (1) or the like based on plexiglass or a material endowed with similar light conduction properties, has an arcuate surface (3) on the side opposite to said display surface ( 2) preferably planar of said plate.

Description

An Arrangement for a Display Device which can be acted upon by light and is provided with a display surface.

The present invention relates to an arrangement for a display device which can be acted upon by light, with a preferably planar display surface with a considerable extent over one plane, this arrangement consisting of a plate or similar object made of plexiglass or a material which displays similar light-conducting properties to those of plexiglass, the said plate, the thickness of which is tapered down towards one of its ends, being designed to admit the effective light in a direction from toe end opposite to the end where the thickness is tapered down, along the display surface to the interior of the plate for subsequent refraction in the plate before it emerges in the direction of the display surface.

The main object of the present invention is primarily to provide an arrangement of the above-mentionedkind wherein the light is dispersed effectively over the whole of its display surface.

The said object is achieved by means of an arrangement according to the present invention which is essentially characterised in that the plate has a substantially curved convex surface which has a great number of recesses made in it, for example by knurling, blasting or stamping, with light-refracting surfaces disposed extending transverse to the light entering from the direction of the plate end.

The invention is described below by way of a number of preferred embodiments, with reference to the accompanying drawings, on which

Figure 1 shows a plurality of display device plates adjoining a common light-source, viewed along the direction in which the light is refracted,

Figure 2 shows two parallel-connected plates, Figure 3 shows the plates in Figure 2 viewed from the direction of their curved sides,

Figure 4 shows a plurality of plates series-ccnnected in a row, viewed from the side, Figure 5 shows the plates in Figure 4 viewed from the direction of their curved sides,

Figure 6 shows a plurality of double-mounted seriesconnected plates,

Figure 7 shows the arrangement associated with a light-source with a rotatable casing,

Figure 8 is a cross-section through the casing and the light-source shown in Figure 7,

Figure 9 shows a drive arrangement appertaining to an arrangement as shown in Figures 7 and 8, Figure 10 is a cross-section through a drive wheel which drives the casing round the light-source, and Figures 11 and 12 show two embodiment examples where the arrangement is being used in a so-called image-distorter. According to the invention the display device comprises a plurality of plates 1 each made of a material with light-conducting properties. A suitable material for this is plexiglass or a material with similar properties to those displayed by plexiglass. The said plate 1 is expediently formed from part of a piece made in the form of the segment of a circle, as is shown clearly, for example, in Figure 1, where plates 1¹, 1² with different shaping are shown.

The plate 1 has a display surface 2 which is preferably planar. On the face opposite to the said preferably planar display surface 2 of the said plate 1 , the plate 1 has a curved surface 3. The said curved surface 3 may be double-curved over an outer pointed part 4 of the said plate 1 in order to improve the effect of the arrangement. The curved surface 3 may be polished and coated, for example with reflecting paint, or it may be chromed or treated in some other way with a view to increasing the light reflecting capacity, and/or it may be provided with transverse grooves for the same purpose. However, it is most expedient to blast the said surface 3, possibly with subsequent surface-treatment. A diffusor 5 which acts in a manner which is known per se can be disposed over the preferably smooth or blasted display surface 2, for the purpose of collecting the light on the front face A of the plate. The blasting on the surface 3 is for the same purpose. Between the display surface 2 and the reflecting surface 3 there extends a preferably planar light-admission surface 6, preferably disposed at right-angles to the display surface 2, and preferably smooth.

In the vicinity of the said light-admission surface 6 on the respective plates 1 there is a light-source 7 which can be of a known type, such as a light tube, an incandescent lamp, etc., for example. The light may also be guided in the direction of the said respective lightadmission surfaces 6 by means of a mirror, for example. The light from the said light-source 7 strikes the plate 1 via the surface 6, substantially parallel with the surface 2, in the direction of the arrow 8. The curved reflecting surface 3 now reflects the light so that it is conducted substantially in a direction out through the display surface 2, as shown schematically by the arrow 9 in Figure 1.

The displaying of various images, symbols, etc., or the provision of uniform display illumination can be effected or obtained in this way with the said arrangement. Figures 2 and 3 show how a common light-source 7 is used for plates 1 disposed on either side thereof with a view to obtaining a light-actuated display device designed according to the present invention.

Figures 4 and 5 show a plurality of plates 1 connected together in series to form a strip with the respective outer ends 4 of the said curved surfaces 3 adjoin ing the said light-admission surfaces 6 on the respective plates 1. A light-source 7 is located at the respective light-admission surfaces 6 and the said arrangement enables a whole wide display surface 11 to be produced from the said plurality of smaller display surfaces 2 without any interrupting joins occurring.

Figure 6 shows an arrangement for producing two wide display surfaces 12 and 13 respectively, facing in opposite directions from each other. This is made possible by series-connecting a plurality of plates 1 in parallel rows with the curved surfaces 3 on the respective plates 1 disposed facing towards each other and connecting the respective plate pairs 14, 15 etc. to a preferably common light-source, Figures 7 and 8 show an arrangement wherein a plate 1 is connected to a light-source 7 which is enclosed in a patterned, etc., transparent cylinder 18 which is operated via a motor 17 as shown in Figures 9 and 10, by a cable 18 and/or a drive wheel 19 mounted on an arm 20, causing it to be driven in the direction of the arrow 21 so that a moving pattern 22 is transmitted to the plate and is shown on its planar display surface 2 in accordance with the above-mentioned principle.

Figure 11 shows a plate 1 associated with a lightsource 7 and a reflector 23 which spreads the light uniformly, situated behind the light-source 7. A distorted image 24 such as a diapositive image, for example, which is located between the light-source 7 and the lightadmission surface 5 is shown with its correct proportions when displayed on the front face 2 of the plate.

Figure 12 shows how a diapositive image 25 or the like is lit by a light-source 7 which again co-acts with a reflector 26. The image is thereby distorted in a lens system 27 so that a distorted image 28 is obtained, substantially the same size as the edge 6 of the plate 1. When the image is displayed on the front face 2 of the plate it assumes its correct proportions again, but is magnified.

The theory of the above is as follows: In the light plate 1 the loss of light with distance is compensated. The weaker beam of light further away from the lightsource 7 is compensated by projecting it on an increasingly small surface P2, P1. The light is reflected at the surfaces and out through the front face 2.

The shape of the projecting plate is part of the segment of a circle.

The radius Rx, Ry of the circle is determined by the following, amongst other things: a) the loss of light with distance b) the dispersion of the light, i.e. how parallel are the light beams entering the plate c) the strength of the light-source d) an index can be established giving the loss of light with distance in the plate.

From this, one or more radii can be found which give uniform excellent illumination, over the whole plate. One suitable shape would be obtained if the surface 3 were formed as a parabola. It will be seen from the above that there is a link between the surface of the plate and its thickness. To put it simply, the thickness of the plate can be increased from the index. This index is influenced by lenses, for example, (the parallelity of the incident light), the strength of the light-source and, if applicable, by different types of transparent material in the plate. A process for producing an arrangement as described above can be effected by extruding, or by pressing the material of a plate-shaped workpiece with a grooved and/ or blasted stamping tool so that two curved surfaces 3 are formed, after which the workpiece is cut in the zone between the said curved surfaces 3 and, optionally, subsequent chroming or some other surface treatment may be carried out on the said curved surface 3 of the respective plates 1.

Examples of fields of application for the abovementioned device are as follows: Displaying photographs, images, firms' names or the like at trade fairs, exhibition sites, etc. The dimension in the depth direction of the light plate is around 1/10 of that of a conventional light panel. The new light plate is more compact and less bulky to transport, and is less susceptible to damage.

Displaying X-ray images in hospitals. The arrangement allows easier installation due to its format, which eliminates the building-in of a light panel into the wall, which is the usual practice at the present time. Greater possibility for sterile conditions and proper hygiene at a lower cost is also made possible. The operator can study X-ray pictures without leaving the sterile zones of the operating theatre since, for example, the images can be displayed suspended from the ceiling or on an adjacent stand.

Previously light panels were rarely used in the wards for X-ray pictures; these were generally studied against a window, etc. The new light plate can easily be taken along on the trolley used when making the rounds, Displaying negatives and diapositives in photographic businesses and studios, for example, in photographic shops, advertising agencies, photographic studios, architects' offices and hobby centres, and some of the advantages are that it is cheaper and more compact than the normal light panels. It is also possible to provide portable lightboards which can be laid directly on a desk.

Shop signs for facades, which give a more uniform illumination with easier and cheaper maintenance.

Lighted signs for display windows and inside business premises. Advertisements for goods, for example, in shops and department stores for the individual depart ments.

Illuminated road signs, providing compact and durable signs where the light fittings can be protected in poles, for example. Indicator lights and brake lights for vehicles, eliminating the costly and conventional light reflectors and reducing the weight and volume of the vehicle, which is the aim of all manufacturers today.

Instrument lighting of various kinds, reducing the risk of dazzle and providing a compact unit.

Illuminated walls, counters, ceilings, floors and shelves, such as reception desks, bar counters, ceiling fittings, illuminated steps and stairs, etc.

For optical traffic beacons of the type based on the so-called moire effect, where the single line system reduces the depth of the light panel. This means that the range of application and the durability are increased and maintenance reduced.

The invention is not limited to the embodiment examples described above and shown on the drawings, but may be modified within the framework of the following Patent Claims without exceeding the concept of the invention.

Claims

P a t e nt C l a i m s

1. An arrangement for a display device which can be acted upon by light and has a preferably planar display surface (2) with a considerable extent over one plane, this arrangement consisting of a plate (1) or similar object made of plexiglass or a material which displays similar light-conducting properties to those of plexiglass, the said plate (1), the thickness of which is tapered down towards one of its ends, being designed to admit the effective light in a direction from the end (6) opposite to the end where the thickness is tapered down, along the display surface (2) to the interior of the plate for subsequent refraction in the plate (1) before it emerges in the direction of the display surface, characterised in that the plate has a substantially curved convex surface (3) which has a great number of recesses made in it, for example by knurling, blasting or stamping, with light-refracting surfaces disposed extending transverse to the light entering from the direction of the plate end (6).

2. An arrangement according to Patent Claim 1, characterised in that the light plate (1) is formed from part of a piece shaped as the segment of a circle, which is preferably formed with a double curved section at the reflecting surface.

3. An arrangement according to either of Patent

Claims 1-2, characterised in that the said curved plate surface (3) is polished and coated with reflective paint, chromed, or the like, with a view to increasing its lightreflecting capacity.

4. An arrangement according to any of the preceding Patent Claims, characterised in that the plate has a planar light-admission surface (6), preferably smooth and preferably extending at right-angles to the display surface (2).

5. An arrangement according to any of the preceding Patent Claims, characterised in that the curved surface (3) on the plate (1) adjoins a planar light-admission surface (6) extending substantially at right-angles to the plate display surface of a further plate (1) located adjacent to the first plate (1) and disposed to form a row, with a light-source (7) situated at the said lightadmission surface.

6. An arrangement according to any of the preceding Patent Claims, characterised in that two plates are located next to each other with their curved surfaces (3) facing towards each other, and a light-source (7) is disposed between the plates (1).

7. An arrangement according to any of the abovementioned Patent Claims, characterised in that the lightsource contains an illuminated image which is transmitted via a movable, preferably rotatable, cylinder (16), via a lens (27) or directly, to an adjoining plate (1).

8. An arrangement according to Patent Claim 7, characterised in that the rotatable cylinder (16) is designed to be operated by means of a cable (18) and/or a drive wheel (19) designed to rest against the cylinder (16), which are driven by a motor (17).