WO2008065668A1

WO2008065668A1 - Lenticular display device

Info

Publication number: WO2008065668A1
Application number: PCT/IL2007/001481
Authority: WO
Inventors: Itzhak Bar Yona
Original assignee: Itzhak Bar Yona
Priority date: 2006-11-30
Filing date: 2007-11-29
Publication date: 2008-06-05
Also published as: EP2102841A1; IL179731A0

Abstract

The invention is a lenticular display unit comprising a front lenticular panel; an indicia carrier, preferably in the form of a plastic or paper sheet, on which an interlaced print is created; a rear panel and pressing means based on the use of magnetic attraction, for pressing said rear panel and as a result said indicia carrier, against the rear face of said lenticular panel; regulating means for aligning the printed indicia carrier with the lenticular panel; drive means and guiding means coupled to at least one of the panels is added in the case of dynamic units.

Description

LENTICULAR DISPLAY DEVICE

Field of the Invention

The present invention relates to the field of lenticular displays. Specifically the invention is a lenticular display unit, capable of passively or dynamically displaying multi-image presentations.

Background of the Invention

Lenticular display units of various kinds are known. Such displays are used for advertising, instructional purposes and the like. They exist in both passive and dynamic versions. The basic optical principle of displacing a complex lithographic print relative to a lenticular linear lens array, either manually or by means of a geared motor, is known from the prior art, e.g. US Patent 5.494.445 discloses general know-how for consecutively displaying several images, Japanese published patent application 02211437 by Kumagai, and US 6,226,906 by the inventor of the present invention.

In lenticular technology three basic conditions must be satisfied:

1. The information lines of the lithographic print have to be positioned in the focal points/lines of the lenses belonging to the lenticular panel.

2. The pitch distance between the information lines has to be equal to the pitch distance of the lenses of the lenticular array of lenses. 3. The information lines of the lithographic print have to be aligned with the linear lenses of the lenticular panel.

According to the method commonly used in the prior art, in order to satisfy the first condition and keep the lithographic print at the locus of the focal points of the lenses, the lenticular panel is created with a thickness equal to the focal length of the lenses. The indicia carrier, usually in a form of a printed plastic or paper sheet on which is created the printed information, is attached to the rear flat face of the lenticular panel. As a result of this arrangement, the indicia carrier remains superimposed on the rear flat face of the lenticular panel, i.e. - in the focal locus of the lenses, when relative movement between the indicia carrier and the lenticular panel is brought about.

While in small lenticular display units it is relatively easy to keep the indicia carrier in superimposed relation to the front lenticular panel this becomes more difficult to accomplish in large format display units. Practically speaking, when a large format unit, e.g. units of 1800mm by 1200mm, sometimes called "city format", with a resolution of 10 lpi (lines per inch) are created, the distance from the printed information on the indicia carrier to the focal locus can vary within a range of up to 0.2mm. If the variation is greater than this, a "ghosting effect", i.e. a partial projection of the neighboring image together with the "main image" takes place. Extruded or injected lenticular panels produced using conventional techniques have a uniform thickness within the above limitation; however, they are never really planar. Therefore, unless very special and costly efforts are made in producing the sheets, when the lenticular sheet and indicia carrier are supported in parallel planes there are typically enough locations on a display of this size in which the variations in distance between print and lens exceed the allowed value. In these circumstances the display is useless from a commercial point-of-view. For this reason it is not possible to create large format displays using prior art display devices, such as the one described in JP 02211437. The display unit taught in this publication consists of attaching the planar indicia carrier to a rigid frame and displacing it parallel to the frontal lenticular panel. It is clear that this does not even address the problem of compensating for the deviations from a planar surface of the backside of the lenticular panel. A practical solution has been described in international patent application WO 02/23510, by the inventor of the present invention. In this application, means are disclosed for maintaining the required spatial relationship between the indicia carrier, on which the information to be displayed is printed, and the lenticular panel used to display such information: A resilient means, such as a fleece mattress supported by a rear panel, is placed such that it uniformly presses the indicia carrier against the rear face of the lenticular panel, even when relative movement occurs between them. If the indicia carrier consists of a simple plastic sheet, than the printed information, being pressed against the rear face of the lenticular panel will always be maintained at the focal distance of each and every one of the lenses, even if the lenticular panel is not perfectly planar.

Although the method of WO 02/23510 provides a practical solution to the problem of creating large format displays, this method has nevertheless several drawbacks. In particular, a disposable plastic or paper sheet has almost no rigidity; therefore, it is very difficult to maintain its alignment with the lenticular panel while subject to constant movement. To overcome this difficulty, additional plastic lamination is applied to the printed-paper sheet, enhancing its rigidity. The increase in rigidity means that the laminated print is more resistant to the perpendicular pressure exerted on it by the fleece thereby reducing the effectiveness of the attachment of the printed information to the lenticular lens sheet.

In addition to establishing and maintaining the correct distance between the print and the lenses, there are a number of other considerations that act together to prevent the development of practical, commercially acceptable large format dynamic lenticular display systems. Some of these considerations are: - Since the extrusion of the lenticular panel and the printing of the indicia carrier are carried out using unrelated manufacturing processes, it is practically impossible to attain a perfect common pitch for both of them and even more difficult to establish equality of cumulative pitch distances between the lenticular panel and the printed lines of information.

- There is a long felt need, especially by media companies, to upgrade existing passive signs into dynamic multi image ones. Attempts have been made to install lenticular display units within the light boxes of existing bus stop station signs, such as shown for example in Fig. 1. Since the width of the empty space in the interior of such light boxes is sometimes limited to less than 40mm, it is quite impossible to use for this purpose, a robust frame such as is used attempting to maintain the spatial relationships between the various elements of the dynamic displays made according to existing methods.

A display unit that overcomes or minimizes many of the difficulties of the prior art has been described in international patent application WO 2005/124432, by the inventor of the present invention. In this application is described a lenticular display unit for displaying consecutively changing images. The display unit comprises a complex transparent lenticular panel, comprised of two superimposed planar transparent panels that can be displaced relatively to one another by activating drive means. The first of the transparent panels is a lenticular panel comprising an array of linear lenticular lenses on its front face and a planar rear face and the second of the transparent panels has smooth front and rear faces. The two transparent panels are pressed against each other by against each other by several pressing means, which in preferred embodiments are pins that are distributed over the surface of the panels. The pins are designed so that they can move in slots with one of the panels relative to the other while maintaining the distance between them. An indicia carrier is attached to the rear face of the second transparent panel and when the drive means are activated, the lines of print of an interlaced print printed on the indicia carrier is periodically displaced relative to the focal locus of the lenticular panel thereby causing the basic images of which the interlaced image is comprised to be consecutively displayed. The main drawback of this display unit is the attachment of the indicia carrier to the rear face of the planar panel. The most practical way to do so is to use a pressure sensitive layer over the print or the panel, preferably a peel able one. The result is rather good; nevertheless the maintenance of such procedure is rather cumbersome. It cannot be implemented in the field and involves the use of special equipment to be used in a central point of assembly.

It is an objective of the present invention to provide a frameless, thick dynamic lenticular display unit, capable of being integrated into the interior of existing passive signs.

It is another objective of the present invention to provide a display unit that can leave the factory having a preliminary given size, and be cut to measure by the final user without dissembling the existing passive sign.

It is yet another objective of the invention to provide a lenticular sign in which alignment of the printed indicia carrier relative to the lenticular panel can be regulated on sight by the end user or by an untrained worker.

Finally it is the objective of the present invention to provide a large billboard unit, comprising numerous modular units in order to present large advertising messages over the entire surface of the billboard.

Further purposes and advantages of this invention will appear as the description proceeds. Summary of the Invention

In the present application, the following definitions are used:

- A lenticular panel is a transparent panel with a front face comprising an array of linear lenses and a planar rear face. - The focal distance of a lens is the distance between the center of the frontal curved surface of the lens and the point/line of convergence of parallel light beams that pass through the lens.

- The focal locus of a lenticular panel is the geometrical location of points located at the focal distance of its array of lenses. - A dynamic lenticular display unit is a display unit capable of displaying two or more alternating images. A dynamic lenticular display unit is comprised of: a lenticular front panel; indicia carrier including a lithographic interlaced print; and drive means causing relative movement between said lenticular panel and said indicia carrier.

- A passive lenticular display unit has the same components without the drive means to cause the relative movement between the indicia carrier and the lenticular panel.

- An interlaced print is a composed lithographic print, consisting of lines of information, received by slicing and interlacing two or more basic images.

- Pitch distance of a lenses array is the distance between the centers of two adjacent lenses.

- Pitch distance of an interlaced print is the distance between the centers of two adjacent information lines.

- Cumulative pitch distance of a lenses array or an interlaced print is the distance between the centers of the first and the last lenses/ information lines in the array/print.

According to the present invention, a dynamic lenticular display unit is created from a front lenticular panel; an indicia carrier, preferably in the form of a plastic or paper sheet, on which an interlaced print is created; a rear panel and pressing means based on the use of magnetic attraction, for pressing said rear panel and as a result said indicia carrier, against the rear face of said lenticular panel; regulating means for aligning the printed indicia carrier with the lenticular panel; drive means and guiding means coupled to at least one of the panels is added in the case of dynamic units. As a result of its structure and its mode of operation, a display unit according to the invention has several advantages over the prior art.

Specific examples of these advantages are:

- Since a robust constructional frame is not necessary to support the indicia carrier relative to the lens sheet, the display unit of the invention can easily be installed in passive, already existing signs, upgrading their ability to display "eye catching" moving images. - Dynamic or passive display unit according to the invention can be produced in a given dimension and cut to the exact measure of the existing light box by the end user.

- Replacement of the indicia carrier is easy to execute even by untrained technicians. - Having no supporting frame the unit, according to the invention is a kind of simple "active poster" which can be produced, shipped and assembled at a minimum cost.

- Very large billboards can be created using the graphical effects of lenticular technology, such as — changing flips; animating figure; morphing and 3D effects.

In a first aspect the invention is a large format display unit for displaying consecutively changing images. The display unit comprises: a. a front transparent lenticular panel; b. a rear planar panel located behind and superimposed upon the lenticular panel; c. an interlaced image printed on a surface located behind and superimposed upon the lenticular panel; d. a plurality of pressing means, comprised of small magnets and complementary magnets or simple metal plates, the pressing means spread, over the area of the two superimposed panels, pressing them one against the other, thus maintaining the interlaced image in the locus of the lenses of the lenticular panel; and e. aligning means for adjusting the printed information of the interlaced image to the lenses of the lenticular panel.

The interlaced image can be printed on an indicia carrier comprising a plastic or paper sheet or on either the front or rear surface of the rear planar panel. If the interlaced image is printed on an indicia carrier, then the front transparent lenticular panel has a thickness substantially equal to the focal length of its linear lenses and the indicia carrier is attached to the front surface of the rear planar panel. In embodiments in which the interlaced image is printed is the front surface of the rear planar panel, the front transparent lenticular panel has a thickness substantially equal to the focal length of its linear lenses. If the interlaced image is printed is the rear surface of the rear planar panel, then the combined thickness of the front transparent lenticular panel and the rear planar panel has a thickness substantially equal to the focal length of the linear lenses.

The display unit of the invention may also comprise a geared motor and transmission means coupled to the geared motor. Activation of the motor brings about a periodical relative displacement between the printed interlaced image and the lenticular panel so as to dynamically display the latent images of the interlaced image. In preferred embodiments the transmission means is an eccentric cam. In one embodiment of the display unit of the invention the pressing means are comprised of an array of small magnets embedded in the front lenticular panel, miniature steel balls scattered over the front face of each of the magnets, and a complementary array of iron plates embedded in the rear planar panel.

In another embodiment of the display unit of the invention the pressing means comprise, an array of magnets fixed to the rear panel and a complementary array of magnets capable of freely moving within a recess, created in the front lenticular panel.

In preferred embodiments of the lenticular display unit of the invention, the print of the interlaced image is aligned with the lenses on the lenticular panel by means of eccentric pins, which fit into holes in the rear transparent panel and can be manipulated so as to bring about the required alignment.

In another aspect the invention is a billboard comprised of: a. a plurality of the lenticular display units of the first aspect of the invention; b. a geared motor; c. transmission means coupled to the geared motor, such that activation of the motor brings about a periodical relative displacement between the printed lenticular image and the lenticular panel so as to dynamically display the latent images of the lenticular image; and d. synchronization means.

Each of the lenticular display units projects a part of the entire image to be displayed on the billboard. The synchronization means enable the plurality of lenticular display units to act in unison, thereby projecting very large images spread over the entire billboard. AIl the above and other characteristics and advantages of the invention will be further understood through the following illustrative and non-limitative description of preferred embodiments thereof, with reference to the appended drawings. With specific reference now to the figures in detail, it is stressed that no attempt has been made to show structural details of the invention in more detail than necessary for a fundamental understanding of the invention, the description taken with the drawings making apparent to those skilled in the art, how the several forms of the invention may be embodied in practice. Most of the following descriptions refer to dynamic display units; nevertheless the invention is also directed to passive units, which are constructed according to the same principles, with the exclusion of driving means as will be further described.

Brief Description of the Drawings

- Fig. 1 is a perspective view of display units installed in a bus stop station;

- Fig. 2A is a horizontal cross section in a display unit according to the invention; - Figs. 2B and 2C are enlarged details of the pressing means and the drive module of the display unit of Fig. 2A;

- Fig. 3A is a perspective view of a display unit, similar to the one shown in Fig.2A;

- Fig. 3B is a perspective cross section, showing an embodiment of the pressing means of according to the invention;

- Figs. 3C and 3D are perspective cross sections showing details of areas E and D respectively in Fig. 3A;

- Fig.4 is a perspective view of a billboard frame, according to the invention; - Fig.δA is a perspective view of the entire system of the billboard shown in Fig. 4; and - Fig. 5B is an enlarged detail of section F in Fig. 5A.

Detailed Description of the Invention

Fig. 2A is a horizontal cross section of a dynamic display unit, according to the invention. It comprises front lenticular panel 1 and rear planar panel 2, with an indicia carrier 3, in a form of printed sheet, held between them by being attached to the front surface of rear panel 2. Various ways of attaching indicia carrier 3 to rear panel 2 will be known to skilled persons. For example pressure sensitive tape can be used or the indicia carrier can be hooked on two or more pins protruding from planar panel 3. The latter method has the advantage of providing an initial alignment of the printed information as it is being attached to the panel. Lenticular panel 1 and planar panel 2 are pressed against each other by means of pressing means 4 distributed all over the surface area of panels 1 and 2. Drive module 5 is responsible for the relative movement between the two panels.

Fig. 2B, which is a magnified view of regions A Fig. 2A, shows one embodiment of the unique arrangement 4 of the invention for holding print 3 in the focal locus of lenses 16 embossed on panel 1. Magnet 6 (one of many, distributed over the entire surface of panel 1) is firmly embedded in front lenticular panel 1. Complementary iron disk 7 is embedded in rear planar panel 2. Small iron balls 8 are freely scattered in a recess in panel 1 in front of magnet 6. The depth of the recess is such that balls 8 touch indicia carrier 3 when it is in its normal position pressed between panels 1 and 2.

Iron balls 8 can freely roll in the recess and are capable of transmitting the magnetic force of magnet 6 to disk 7 through indicia carrier 3. A significant attraction force is thus created between panels 1 and 2 without preventing relative movement between them that can take place without the presence of excessive frictional force.

Because the area of magnets 6 is negligible relative to the area of the entire image to be displayed and the total friction created by them is minute because of the presence of the rolling balls 8, it is possible to install sufficient pressing means of this kind over the area of the display unit to guarantee the position of the printed information of indicia carrier 3 at the locus of the lenses of lenticular panel 1, even while continuous reciprocating motion is taking place between them. A frameless, inexpensive dynamic multi image display unit is thus achieved, which satisfies all of the requirements of lenticular technology.

Fig. 2C is an enlarged cross section of area B in Fig. 2A. Shown is geared motor 9 coupled to eccentric cam 10. Geared motor 9 is fixedly attached to rear panel 2 and eccentric cam 10 is inserted into elliptically-shaped recess 11, which has been created in panel 1. Reciprocating displacement of the front lenticular panel 1 relative to the indicia carrier 3, which is attached to rear panel 2, takes place whenever cam 10 is rotated by motor 9. The dimensions of the relative parts of the transmission system and pressing means are determined such that the distance moved by the magnets 6 relative to the discs 7 will not exceed that at which the magnetic force between them will be insufficient to press the two panels against each other.

Fig. 3A is a perspective view of another embodiment of the display unit 100' of the invention. Display unit 100' comprises two guiding means 12, whose purpose is to maintain the alignment between the lenticular panel 1 and rear planar panel 2. The details of guiding means 12 are shown in Fig. 3C, which is an enlarged view of area E in Fig. 3A. Guiding means 12 comprises a support 21 attached to the rear panel 2. An axle 15 with a ball bearing 13 on its end is connected to support 21 and protrudes out from the front of rear panel 2 such that the ball bearing 13 fits into elliptic recess 14 created in front lenticular panel 1. The axle 15 of ball bearing 13 is mounted to support 21 asymmetrically and can be turned by a screw driver in order to cause a vertical displacement of one side of lenticular panel 1, causing a sight tilt of the entire panel in order to bring about perfect alignment between front lenticular panel 1 and rear panel 2 onto which indicia carrier 3 (not shown in Fig. 3C) is attached. The alignment of interlaced images of indicia carrier 3 can therefore be adjusted in order to achieve a perfect change of the images without a "ghosting effect" so typical to lenticular technology.

The two guiding means 12 allow limited movement of front lenticular panel 1 perpendicular to the axis of its linear lenses 16. The attractive force of the magnets of the pressing means and the ball bearings 13 of the guiding means 12 in display 100 or 100' do not create significant factional resistance to motion; therefore the power supplied by a relatively small drive-module 9 is sufficient to displace the two panels in a periodic manner relative to each other.

Fig. 3B is a magnified view of area C of Fig. 3A showing another embodiment of pressing means 4'. Cylindrical magnet 30, which is permanently embedded into rear panel 2, attracts a complementary annular-shaped magnet 32, which fits into linear recess 34 created in lenticular panel 1. Annular-shaped magnet 32 is held in position by the end of the shaft of mushroom shaped plastic pin 33, which fits tightly in its hollow center. Indicia carrier 3, which is attached to the front of rear panel 2 is thus pressed between magnet 30 and magnet 32 by the force of their attraction.

The shaft of pin 33 can slide back and forth in the narrow upper part of linear recess 34 and the magnet 32 can slide in the wider lower part of recess 34 thereby permitting limited movement of pin 33, perpendicularly to the lenses, within the space of recess 34. The result is that lenticular panel 1 can be displaced relative to rear panel 2 and indicia carrier 3 while the two magnets do not move relatively each other keeping the printed information on the indicia carrier at the focal points of the lenses; i. e., in this embodiment of the pressing mean, the rear panel, both magnets, and the indicia carrier pressed between the magnets move as a unit relative to the lenticular panel. This means that there is no frictional force on the indicia carrier caused by the magnets (or magnet and metallic disc) moving relative to each other. The only friction is between the print and rear face of the lenticular panel.

The procedure for achieving perfect alignment of the lenticular panel and indicia carrier will now be explained with reference to cross-sectional view Fig. 3D, which is an enlargement of area D in Fig. 3A. Part of front panel 1 has been removed to expose the printed information on indicia carrier 3, showing three vertical printed stripes of different colors: red 17: yellow 18 and blue 19 for example. Before adjusting eccentrically mounted axle 15, a mixed appearance of these colored stripes on superimposed lens 16 is displayed. While facing lenticular lens 16, the user turns axle 15, until he observes one of the colors uniformly spread over all of lens 16. It is now obvious how guiding means 12 serves also as the aligning means that are so critical in lenticular technology.

In order to replace indicia carrier 3, one has to use some force in order to separate lenticular panel 1 from planar panel 2 in order to overcome the attractive force of magnets 6 (or 30,32). In the embodiment shown in Fig.2B, there is no danger of losing the iron balls 8, as they are always attracted to magnet 6 and remain attached to it in its recess.

It is clear that the embodiments described hereinabove with reference to dynamic lenticular displays can also be used mutatis mutandis to create passive lenticular displays. In particular, omitting the drive module 5 and replacing ball bearing 13 of guiding means 12 with a simple eccentrically mounted shaft will result in a simple passive lenticular sign, in which the replacement of messages can be easily achieved by separating the two panels and replacing the indicia carrier.

The invention thus provides a large format dynamic display unit that can be operated by a battery driven, small geared motor. The display can be used in ambient light or installed in the light box of an existing sign such as that shown in Fig. 1. Since the combined thickness of the two panels of the display of the invention is on the order of 6-8 millimeter thick and there is no frame necessary to hold them together, display unit 100, 100' can be simply hooked on the hinged doors, of existing light boxes. No constructional changes are required and the owner of the location can always restore the traditional passive poster mode of operation, if and when he chooses to do so.

Another object of the present invention is to provide a huge billboard comprising of numerous modular units, such as display 100' described with reference to Fig.3A. Fig. 4 shows a rigid supporting frame 23, divided into three modular sections. Display units 100' of the kind described in Fig. 3A can be installed in frame 23 in order to achieve a larger billboard, presenting huge advertising messages. A solution to the problem of synchronization between the three modular units 100' will be illustrated with reference to Fig. 5A showing the complete billboard. In step one the entire interlaced print is prepared on a computer and printed on an indicia carrier. Then the indicia carrier is divided into three separate sections. Vertical colored strips of the kind described in Fig. 3D are separately printed on the right edge of each section of the print. Each section of indicia carrier is attached to its corresponding display.

Initially the rear planar panel of each modular unit 100' is secured to frame 23 as a stationary element. Each section 100' comprises its own adjusting means 12 in the form of an eccentrically mounted axle, such as described in Fig 3C. The technician that installs the display in the billboard separately registers each modular unit, choosing a common vertical stripe of a given color. When all the units are adjusted to the same vertical stripe (color), the entire image will be displayed on the billboard. In order to dynamically synchronize the units, the technician now uses horizontal bar 26 to connect the front lenticular panels to drive module 5, as seen in detailed Fig 5B. The connection is done by inserting pins 28 into elliptic recess 29 and securing both by threading knob 20. When drive module 5 is switched on, horizontal bar 26 simultaneously transfers the movement to the front lenticular panels and the latent images of the interlaced print are sequentially displayed.

The embodiments of the display unit of the invention described hereinabove all comprise an indicia carrier, on which is printed an interlaced image, sandwiched between a front lenticular panel and a superimposed rear planar panel. Alternate embodiments of the invention can be produced in which the interlaced image is printed directly onto one of the surfaces of the rear planar panel, thereby eliminating the necessity of using a separate indicia carrier. The printing can be done on either the front surface of the planar panel or on its rear surface. In the latter case, the thickness of the lenticular panel is reduced, such that the combined thickness of the two panels is equal to the focal length of the lenses. This results in a display unit having the minimum thickness that is theoretically possible. These embodiments of the invention are particularly useful in situations in which the display is rarely changed.

Claims

1. A large format display unit for displaying consecutively changing images comprising: a. a front transparent lenticular panel; b. a rear planar panel located behind and superimposed upon said lenticular panel; c. an interlaced image printed on a surface located behind and superimposed upon said lenticular panel; d. a plurality of pressing means, comprised of small magnets and complementary magnets or simple metal plates, said pressing means spread, over the area of said two superimposed panels, pressing them one against the other, thus maintaining said interlaced image in the locus of the lenses of said lenticular panel; and e. aligning means for adjusting the printed information of said interlaced image to the lenses of said lenticular panel.

2. Display unit as claimed in claim 1, wherein the surface upon which the interlaced image is printed is one of the following: a. an indicia carrier comprising a plastic or paper sheet; b. the front surface of the rear planar panel; or c. the rear surface of said rear planar panel.

3. Display unit as claimed in claim 1, wherein the surface upon which the interlaced image is printed is an indicia carrier, the front transparent lenticular panel has a thickness substantially equal to the focal length of its linear lenses, and said indicia carrier is attached to the front surface of said rear planar panel.

4. Display unit as claimed in claim 1, wherein the surface upon which the interlaced image is printed is the front surface of the rear planar panel and the front transparent lenticular panel has a thickness substantially equal to the focal length of its linear lenses.

5. Display unit as claimed in claim 1, wherein the surface upon which the interlaced image is printed is the rear surface of the rear planar panel and the combined thickness of the front transparent lenticular panel and said rear planar panel has a thickness substantially equal to the focal length of the linear lenses.

6. Display unit as claimed in claim 1, comprising: a. a geared motor; and b. transmission means coupled to said geared motor, bringing about a periodical relative displacement between the printed interlaced image and the lenticular panel so as to dynamically display the latent images of said interlaced image.

7. Display unit as claimed in claim 6, wherein the transmission means is an eccentric cam.

8. Display unit as claimed in either claim 1 or claim 6 wherein the print of the interlaced image is aligned with the lenses on the lenticular panel by means of eccentric pins, which fit into holes in the rear transparent panel and can be manipulated so as to bring about the required alignment.

9. Display unit as claimed in either claim 1 or claim 6 wherein the pressing means are comprised of: a. an array of small magnet, embedded in the front lenticular panel; b. miniature steel balls scattered over the front face of each of said magnets; and c. a complementary array of iron plates embedded in the rear planar panel.

10. Display unit, as claimed in either claim 1 or claim 6 wherein the pressing means comprise a. an array of magnets fixed to the rear panel; and b. a complementary array of magnets capable of freely moving within a recess, created in the front lenticular panel.

11. A billboard comprised of : a. a plurality of lenticular display units as claimed in claim 1; b. a geared motor; c. transmission means coupled to said geared motor, bringing about a periodical relative displacement between the printed interlaced image and the lenticular panel so as to dynamically display the latent images of said interlaced image; and d. synchronization means; wherein each of said lenticular display units projects a part of the entire image to be displayed and said synchronization means enable said plurality of lenticular display units to act in unison, thereby projecting very large images spread over said entire billboard.