IMPROVEMENTS IN OR RELATING TO THE DISPLAY OF HOLOGRAMS

Abstract: A combined hologram display unit and clock comprises a body (10) including a casing having, on a front face thereof, a recess (24) to receive a hologram plate (26), located by means of a detachable transparent cover (32) detachably fitted to the front of the casing. A light fitting (45) is carried at the end of a boom (44) and serves to illuminate the hologram plate (26) appropriately. The device may incorporate a digital clock (30). The boom (44) may be detachable, and simultaneously electrically disconnectable from the casing, through the intermediary of a plug and socket connection.

Description: DESCRIPTION OF INVENTION Title: "Improvements in or relating to the display of holograms" THIS INVENTION relates to the display of holograms. Although the development of holograms and holographic techniques has aroused considerable interest generally, exploitation of the.effect at the consumer level and in such areas as advertising and the like has not yet been particularly extensive and one of the reasons for this is that the requirement for a light source oriented precisely with respect to a holographic plate in order for the recorded image to be viewed is one which it is difficult to meet easily in practice. It is an object of the present invention to provide a simple means by which this requirement may be readily met in apparatus which is inexpensive and which is readily usable in the home or in public access buildings, for purposes of decoration or advertising etc. According to one aspect of the invention there is provided an apparatus for use in displaying a hologram comprising locating means for locating precisely in a predetermined position a holographic plate of predetermined dimensions, and a light source, for illumination of a holo- graphic plate so supported, mounted by support means connected with said locating means in a desired predetermined position. According to another aspect of the invention there is provided the combination of a holographic plate and apparatus according to the first- noted aspect, said plate being mounted in said predetermined position in said locating means, said light source being mounted by said support means in a position to display effectively the Image recorded by the hologram. The apparatus preferably comprises a frame, for example a rect- angular frame similar in appearance to a conventional picture frame, with said locating means being disposed within the frame to support a rectangular holographic plate in the desired position within the frame to be viewed through the rectangular area bounded by the frame. In this case the light source may be carried by support means connected with the frame. For example the support means for the light source may comprise a rigid member pivotally connected with the frame, for example to the top of the frame. Thus the light source may be carried at the free end of an arm pivotally connected at its other end with the frame for pivotal movement between a retracted and deployed position so that when it is not desired to view the hologram, the arm can be placed in its retracted position in which it sits snugly and unobtrusively in the frame but can be readily moved to its deployed position. The support means may alternatively comprise two or more relatively pivotable rigid parts forming an articulated arm. In its deployed position, the support means preferably extends in front of the frame and above the level of the top of the frame so that the light source can direct light onto the hologram within the frame without an observer's view of the frame being obstructed by the arm. The arm may, for example, be spring biased with a manually operable catch being provided to hold it in its retracted position. The locating means in the frame may comprise a recess within the frame bounded by portions of the frame for engagement with the marginal edges of, for example, a rectangular hologram plate of predetermined side and shape, to locate the latter accurately in position in relation to the remainder of the frame. The frame may comprise, for example, a readily removable and replaceable back which can be removed to allow a hologram plate to be fitted in position in the frame and replaced thereafter to retain the plate in position. The frame may be adapted, for example, for a hologram plate of post-card size. The frame preferably incorporates a protective transparent front sheet, for example of plastics or glass, to protect the hologram plate. The frame may also incorporate a recess, for example a recess also closed by such a removable back, to accommodate a battery to supply electrical power to the light source. Preferably a manually operable switch is provided at an accessible but unobtrusive part of the frame so that the supply of electrical power to the light source can be terminated when viewing of the hologram is not desired. The frame may be ' adapted to stand freely on a table or the like surface or may be adapted to be fastened to a vertical surface such as a wall. Means may be provided for adjusting the intensity of the light projected by the light source on to the hologram plate, for example, operated by a manual control on the frame. The device may incorporate electrical circuitry whereby the light source is switched on and off at regular intervals. In a variant, the device may comprise a plurality of light sources, for example mounted on a single support means connected with the frame, the individual light sources being disposed in different orientations and positions relative to one another in relation to the hologram plate and the device may incorporate means for energising and de-energising the individual light sources in succession with the hologram plate being arranged, in known manner, to display a different image for each of the il luminated light sources. The images thus displayed successively may, for example, be images, at successive intervals, of a single scene in which one or more objects are in relative motion, whereby the illusion of motion is given to the observer. By way of example, the arrangement may be such that the observer is presented with a view of a hammer moving relative to an egg and finally smashing the egg or with some other such eye-catching scene. It is envisaged that the device may be utilised in a public access building or the like for advertising purposes and in this case it wil l not normally be necessary for the support means for the light source to be retractable. However, in this case the device may suitably be combined with some other eye-attracting element, for example a clock or a moving display, with, for example, the holographic images comprising or being incorporated in advertising or the like material. An embodiment of the invention is described below by way of example with reference to the accompanying drawings in whϊch:- FIGURE I is an exploded perspective view of a combined hologram display unit and clock embodying the invention, FIGURE 2 is a partially exploded side view of the unit of Figure I , and FIGURE 3 is a rear view of the unit of Figures I and 2. Referring to the drawings, a combined hologram display unit and clock comprises a substantially rectangular body 10 providing a substantially flat major front face 12, side faces 14 and upper and lower faces 16. The body 10 has a rear surface 18, the major part of which is substantially flat and parallel with the front face 12 but is provided with recesses to accommodate, in a folded position, a pivotally mounted strut or support 20. The body 10 comprises a plastics casing including a generally rectangular shallow shell providing a major rectangular wall 22 with respective further walls extending from the edges of wall 22 perpendicular with the wall 22 to afford a rim which provides the side faces 14, 16, and within which rim is fitted, on the rear of the body 10, a rectangular plastics plate 23 which affords the rear surface 18 of the body 10, the plate 23 being secured to the front casing part by screws 25. In the front surface of the major wall 22, a shallow rectangular recess 24 is formed which receives a rectangular hologram plate, of corresponding dimensions, indicated at 26. Below the recess 24, the front wall of the casing is provided with a rectangular aperture 28 through which there is exposed to view the digital display 30 of an electronic digital clock, for example a digital alarm clock, accommodated within the casing. The casing is provided with a cover 32 of transparent plastics which protects the hologram plate 26 and display 30 and also serves to retain the hologram plate in place in the recess 24. The cover 32 is in the form of a flat optically transparent rectangular plate of the same size and shape as the front face of the casing but which has, at its corners, on its vertical sides, lugs 34 which extend perpendicular to the front of the casing and are accommodated within recesses formed in the side walls 14 adjacent the upper and lower ends of the latter so that the outer surfaces of the lugs 34 are flush with the outer surface of the side walls 14. Each lug 34 has an aperture in which locates a corresponding projection formed on the respective side walls 14 so that the lugs 34 ' are snapped resiliently over the projections to hold the cover in place on the casing and can likewise be resiliently displaced from these projections to allow the cover to be lifted off the casing. However, when it is desired to replace one hologram plate 26 by another, it is merely necessary to disengage the lugs 34 from the casing at its upper end, or at its lower end, whereupon the cover can be pivoted away from the casing about the axis defined by the interengαgϊng projections and apertures of the lugs 34 still engaged with the casing. A socket provided in the casing adjacent the upper end thereof opens onto an aperture in the middle of the top face 16 of the casing and a plug formed at one end of a boom 44 is plugged into the socket 40 and carries, at its other end, a light fitting 45. The light fitting 45 incorporates, in a manner known per se, a light source, such as an electrical filament bulb, a reflector, and a lens all supported in an opaque shell. The plug formed at one end of the boom 44 and the corresponding socket provided In the casing • afford both a mechanical connection between the boom 44 and the casing and an electrical connection between electrical circuitry within the casing and electrical conductors which extend within the boom 44 to the light source in the light fitting 45. As shown, the boom 44 is so shaped that the light produced in the light fitting 45 is directed onto the hologram plate 26. The boom 44 and light fitting 45 may be detached from the casing when not required, for example where other available light sources are adequate to provide effective display of the hologram. As shown, the rear of the casing is provided with a strut 20 which can be swung out into the extended position shown in Figures I and 2 in order to allow the casing to be propped up for display on a flat surface such as a table. The strut 20 can, alternatively, be folded away, to a position in which it does not stand proud of the major flat portion of the rear surface 18 of the casing and in which position the unit may simply be laid flat upon a surface such as a table or may be hung on a flat vertical surface such as a wall, for example through the intermediary of keyhole slots 60 formed through the rear cover plate 23 and communicating with an enlarged space or spaces within the casing, whereby the body may be fitted over screws screwed partially into the wall or the like providing the flat vertical surface whereby the device can be simply hooked over the heads of such screws or the like. A socket 66 provided in one side wall 14 of the casing is adapted to receive a plug (not shown) provided at the end of an outlet lead (not shown) of a transformer plug, not shown but known per se, intended to the plugged into a mains socket to supply the unit with low tension electricity via the socket 66. Alternatively, or in addition, the unit may be provided with batteries, housed within the casing, for the supply of electricity to the lamp 45 and the electronic digital alarm clock. On one side wall 14 of the casing there is provided a series of buttons 68, flush with the surface of the side wall, for control and the setting of the digital clock.

Claims: CLAIMS 1. Apparatus for use in displaying a hologram comprising locating means for locating precisely in a predetermined position a holographic plate of predetermined dimensions, and a light source, for illumination of a holo¬ graphic plate so supported, mounted by support means connected with said locating means in a desired predetermined position. 2. The combination of a holographic plate and apparatus according to claim I , said plate being mounted in said predetermined position in said locating means, said light source being mounted by said support means in a position to display effectively the image recorded by the hologram. 3. Apparatus according to claim I wherein said support means and said light source are moveable between said predetermined - position and a retracted position. 4. Apparatus according to claim 1 comprising a plurality of light sources, each mounted by said support means in a respective different predetermined position in relation to said locating means, and means for energising said light sources sequentially. 5. Apparatus according to claim 1 or claim 2 and substantially as hereinbefore described with reference to and as shown in, the accompanying drawings.

Inventors: JOHNSON WILLIAM NEVIL HEATON, JOHNSON, WILLIAM, NEVIL, HEATON
Applicants: RS PRODUCTIONS LTD, R.S. PRODUCTIONS LIMITED
Application year: 1985
Main classification: G09F19
IPC codes: G03H1, G09F9, G09F19