DE20218785U1 - Lens raster display system uses cylinder lenses with position adjustment - Google Patents

Abstract

The display panel has two or more changing images (4) that are held firmly against cylinder lenses (3). Between the slide plate (5)and the images is a layer of compressible material .Spring loaded rollers (8) press the images against the lenses. Adjustment is provided bay turning the lenses.

Description

The present invention relates to a display device for displaying at least two consecutive images and, in particular, to a display device for displaying two or more alternating images viewable through a lens in the display device.

Display devices that display multiple images are known on the market, but these can be difficult to use due to their low resolution and the poor positioning between the display card or other display element and the lens through which the image is

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being viewed do not show accurate images and fonts in relatively small fonts.

The invention is therefore based on the object of providing a display device which eliminates or minimizes the above-mentioned disadvantage in a simple but nevertheless effective manner, or at least offers the public a useful choice.

According to the invention, this object is achieved by a display device for displaying at least two consecutive images to be viewed by a viewer, comprising: a housing with at least two wall regions defining a cavity therebetween, at least part of a wall region being made from an arrangement of linear lenses having a lenticular front side and a flat back side, at least one support in the cavity, the support being designed to receive a substantially flat display element in use, and a pressure means for urging the display element against the lens when a display element is located in the cavity.

Preferably, the pressure means includes a plurality of rollers and biasing means for biasing the rollers so that the display element is urged against the lens.

Preferably, the pressure media rest on the display element.

Alternatively, a plate is also provided in the cavity, wherein the pressure means rests on the plate, which in turn rests on the display element.

Preferably, a substantially transparent retaining sheet is positioned substantially against the side of the lenticular lens facing outwardly with respect to the housing.

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Preferably, at least 15 cylindrical lenses per inch (lenticules per inch (Lpi)) are provided in the lenticular lens.

Even more preferably, at least 20 cylindrical lenses per inch (lpi) are provided.
Particularly preferred are at least 30 cylindrical lenses per inch (Lpi).

Preferably, an adjustment means is provided for moving the lens relative to the display element.

Furthermore, it can be provided that the adjustment means can be operated from the outside of the housing.

Preferably, the adjustment means includes a pivot on which the lens is mounted and is operable to rotate the lens about the pivot.

Also preferably, a drive means is provided which is operable for relative movement substantially in the planes between the lens and the display element.

Furthermore, it may be provided that guide means are provided to maintain the lens and the display element in a substantially parallel relationship during relative movement of the lens and the display element.

According to a further particular embodiment of the invention, it can be provided that the drive means contains a motor and a control means is provided to adjust the speed of the motor.

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Furthermore, an adjustment means may be provided to enable a substantially parallel arrangement between the display element and the lens.

It can also be provided that up to twelve consecutive images are visible.

Finally, according to a particular embodiment of the invention, it can be provided that the images viewed appear in 3D.

Further features and advantages of the invention emerge from the claims and the following description, in which two embodiments are explained in detail with reference to the schematic drawings.

Figure 1 shows the difference in resolution between a lens with ten embossed

tiny cylindrical lenses (lenticules) (hereinafter referred to as cylindrical lenses) per inch compared to a lens with 30 cylindrical lenses per inch;

Figure 2 is a schematic cross-sectional view of a display device according to a

preferred embodiment of the invention;

Figure 3 shows an adjustment device for use in the construction of Figure 2 in

side view,

Figure 4 is a plan view of the construction of Figure 3;

Figure 5 the effect of misalignment between the image and the cylindrical lenses,

the left image showing misalignment and the right image showing substantially accurate alignment;

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Figure 6 shows a device covering the group of black lines;

Figure 7 shows a drive mechanism for use in the construction of Figure 2;

Figure 8 shows a gear mechanism which can be used in the construction of Figure 2;

Figure 9 shows a cam arrangement for use in moving a display element or image in the apparatus of Figure 2;

Figure 10-13 a 3D effect due to movement in the structure;

Figure 14 shows ventilation holes in the frame of a housing used for air movement in the construction of Figure 2;

Figure 15 shows an alternative display device in exploded view;

Figure 16 shows an image drive mechanism for use in the construction of Figure 15;

Figure 17 is a cross-sectional view of the construction of Figure 16;

Figure 18 shows an access to the construction of Figures 15 and 16 for replacing a display element; and

Figure 19 is a side view showing the arrangement of Figure 18.

A display device will be described with reference to the drawings.

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A pair of characters are shown in Figure 1. Each of these characters represents the letter "S". The figure on the left is shown with ten lenticules per inch (Lpi) and the figure on the right is shown with thirty lenticules per inch (Lpi). As can be seen, the fineness, or the number of lenticules per inch (Lpi), has a significant effect on the clarity of the image. The higher the number of lenticules, the clearer the image. However, providing a higher number of lenticules per inch requires a much improved positioning between the display element or image and the lenticular lens. In particular, there must be a high degree of contact between the back of the lens and the display element to prevent the image from being out of focus, and the image and lens must be arranged substantially parallel, otherwise the image will be substantially destroyed.

To achieve such a construction, according to a particular embodiment, the construction of Figure 2 is provided.

In this construction, a housing 1 is provided by an outer frame 2. The housing provides a cavity in which the following elements are provided. A lenticular lens 3 is provided together with a display element which may be in the form of an image 4 as will be described in more detail below. The image 4 is arranged closely adjacent the inwardly facing side of the lenticular lens 3.

In the embodiment of Figure 2, a plate 5 is provided, which is preferably a sliding plate. Between the plate 5 and the image 4, a layer of compressible material, such as a sponge foam layer, can be provided.

Furthermore, pressure means are provided for pressing the image 4 against the lenticular lens 3. In this embodiment, the pressure means comprise rollers 8 mounted in a suitable carrier 9, wherein any suitable number of rollers, e.g. four or six such rollers, may be provided. The rollers are e.g. actuated by a compression spring 10 which is arranged in

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a cylinder 11 mounted on a support plate 12 engaging with the outer frame 2, pressed against the plate 5.

In addition, a suitable light source 22 is contained in the housing. The lenticular lens 3 is held in the outer frame 2, for example, by suitable clamps 23.

To reduce and, if possible, prevent deformation of the lens and image due to the pressure of the compression springs 10 and rollers 8, a substantially transparent front panel in the form of a clear plate 24 is provided. This may, for example, be formed from an acrylic sheet. The acrylic sheet is made to any desired thickness, e.g. more than 5 mm. The sponge layer assists in intimate contact of the image 4 with the lenticular lens 3 and may, for example, be 2 mm to 6 mm thick at a density of 6 kg to 25 kg per cubic metre. The sponge layer also has the effect of reducing the force between the image and the lens to the minimum necessary to achieve the desired result.

With regard to the number of cylindrical lenses provided in the lenticular lens 3, it is envisaged that if, for example, a relatively small display is required, e.g. in the range of 15.24 cm x 17.78 cm (6 inches by 7 inches) to 20.32 cm x 30.48 cm (8 inches by 12 inches), essentially 30 lpi may be provided. For larger models, such as 30.48 cm x 43.18 cm (12 inches by 17 inches) to 6.96 cm x 91.44 cm (24 inches by 36 inches), it is considered that 20 lpi will suffice. Larger displays could use fewer cylindrical lenses, such as 10 to 15 lpi.

As can be seen, each compression spring 10 is independent in use and thus the force exerted depends to some extent on the requirements at the particular point. The force of the compression springs compresses the sponge between the plate 5 and the image 4 in such a way as to ensure the best possible contact between the image 4 and the back of the lenticular lens 3.

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The provision of the thick plate 24 reduces any tendency of the structure to become convex with respect to the cavity in use.

Referring now to Figures 3 and 4, the lenticular lens 3 is mounted on a hinge pin 28. The hinge pin 28 is held by a retaining member 29 mounted on the frame 2. The lenticular lens 3 is thus rotatable about the hinge pin 28. For adjustment, a bracket 30 is provided which is mounted on the lenticular lens 3. A rotatable knob 31 is provided which is screwed into and passes through an opening in the bracket 30. The knob 31 is prevented from rotating by engagement with a suitable position, such as the surrounding outer frame 2.

The adjustment means, which is preferably operable from the outside of the cavity, may be contained in a removable cover plate 32 which sealingly engages the main part of the outer frame 2 by means of sealing elements 35 and 36 which may be formed, for example, from silicone rubber.

The adjusting means enables rotational positioning of the image 4 and the lenticular lens 3, that is to say that a substantially parallel arrangement can be obtained between the image 4 and the lenticular lens 3. The effect of this is shown in Figure 5, where the left image shows an image in which the rotational positioning is inaccurate and the right image shows the same image in which the rotational positioning is corrected.

Figure 6 shows a device that covers a group of black lines. This cover plate 40 is movable in slots provided in the outer frame 2 to adjust the positioning between the image 4 and the lenticular lens 3 in a translational manner. The cover plate 40 is movable to slide along the slots provided and is held in position by rotation in the slot. After an adjustment has been made, it is moved to cover the black lines and a small depression (not shown) is made on the cover plate 40, this depression being in the

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slot in the frame so that the cover plate will retain its position during use.

Figure 7 illustrates a drive mechanism. The drive mechanism 50 provides a motor 51 which, in use, is arranged to rotate continuously when a suitable drive signal is received. Two sets of stepping gears are provided for reducing the speed of rotation of the drive shaft 52 which drives a cam 53. A gear changer 54 is provided which is adjustable by means of an element 55 which is manually engageable. This is described in more detail in Figure 8 which shows two gear sets 60 and 61. The gear sets 60 can, for example, reduce the speed of the drive shaft to, for example, between four and eight seconds for a full revolution and the gear train 61 can achieve a reduction of, for example, about 16 to 32 seconds per revolution. The speed is of course controlled by the speed of the motor in conjunction with a suitable electronic control device 65. The electronic control device 65 has three main parts. The first part is a pulse generator. The pulse generator has a fixed capacitor and a variable resistor (VR). By tuning the VR, the pulse frequency is changed. The higher the resistance, the lower the frequency. The pulses go to the second part which has a timer IC to control the duration of the pulses. The regulated pulses go to the device's power supply switch. When a pulse is delivered, the power source is on and the motor runs while the power source is on. When the pulse passes, the power is off and the motor slows down, not stopping due to its inertia. Before it stops, another pulse is delivered and the motor starts accelerating again. The higher the frequency of the pulses, the longer the acceleration, ultimately making the motor run faster, and vice versa. Furthermore, the speed achieved by the gear group 60 and the speed of the gear group 61 are changed by an intermediate gear or a roller in the gear group 62, which can be positioned between a lower gear position 62 and a high gear position 64 by actuating the element 55. The cam 53 is designed in such a way that it allows a linear displacement of, for example, four to six cylindrical lenses of the lens to the image

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in one full revolution of the cam. Since the cam is connected to the drive shaft 52 which rotates at a rate of four to thirty-two seconds per revolution, the image 4 is movable at a rate of two-thirds to eight seconds per cylinder lens. A cam follower 70 is provided which surrounds the cam 53 as shown in Figure 9. The cam follower is attached to the plate 5. The cam follower provides two tips 71 and 72 which contact the cam 53 in opposite positions. As shown in Figure 9, the diagonal distance through the drive center point #0 is constant around the circumference of the cam. As the cam rotates from a position "A" to a position "B", the tip 71 of the cam follower is moved forward a distance determined by parameters of the design. However, when the cam moves from a position "C" to a position "D", the tip 72 is moved to return the cam follower to its initial position. Since the cam 53 pushes the cam follower 70 and the cam follower 70 is fixedly attached to the platen 5, the image can be driven up and down or left and right at a constant speed.

Referring to Figures 10 to 13, a horizontally moving lenticular lens 3 is provided, with the cylindrical lenses extending vertically.

An image to be displayed is indicated at 80, images of the picture having been taken at positions "A", "B" and "C" in Figure 10. Thus, an image is made between positions "al" and "a2" of position "A", between "bl" and "b2" of position "B" and between "el" and "c2" of position "C". When these are correctly positioned on the display element 4, the effect is as shown in Figure 13. In the left hand position, the lenticular lens 3' is shown at the position of the image which is e.g. B. contains the image taken from the position "B" in Figure 10. Thus, "bl" to "b2" of the image are seen. If the image has moved so that the lenticule lens 3 ^λ is located, for example, at the position "A" as shown in Figure 13, then the image is reproduced as viewed from the position "A" in Figure 10. By appropriately designing the cylinder lens,

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a significant number of consecutive images can be obtained. It is possible to obtain at least twelve consecutive images. The images appear to exist in three dimensions due to the different angles on the lenses.

Referring to Figure 14, to provide a substantially watertight construction, the silicone seals described above are used. However, it is desirable to pass air through the construction and this can be achieved by providing ventilation holes 90 on the inner part of the frame and ventilation holes 91 on the outer part of the frame, these holes being non-aligned and preferably the outer ventilation holes 91 being positioned lower so that air can spread but rain is at least substantially prevented from passing through the inner ventilation holes 90. A fan 92 may be provided for driving air, particularly to assist in cooling and thus is designed to turn on when the light in 22 is turned on.

Referring now to Figure 15, there is shown a simplified structure. In this simplified structure, which is intended for use in the home as a small unit, it is possible to remove the cooling fan 92, the light source 22, the transformer 93 and also the panel 5. Various seals may also be removable. Furthermore, it is intended that the device be battery operated.

Although the image 4 is lighter, it is nevertheless stiff enough and can be driven directly by the mechanism. In this construction, the rollers 8 can rest directly on the image. The lenticular lens 3 is visible through an opening 100 in the frame, which comprises a front frame unit 101 and a rear frame unit 102 which are engageable with each other. The cam follower 70 is mounted directly on the image so that the cam 53, which functions in the same way as before between the tips provided in the cam follower, drives the image 4 directly. Figure 16 shows the image drive mechanism

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of this display device. The cam 53 drives the cam follower 70 which essentially replaces the cam follower and slide bed of the previously described construction. The image is positively guided by a pair of guide rails to provide the required positioning as the image moves. A guide sleeve 107 is provided. The guide sleeve 107 is guided by a pin 108 which rides in a slot 109 in the plate 107. The gap between the plate 107 and the guide rails and the gap between the guide sleeve and the guide pin is less than 0.0127 cm (0.005 inches). This allows satisfactory control to cause parallel movement of the image in response to the sliding of the cam.

A cover plate 110 is provided for covering an opening 111 in the frame member 101 to provide access to the cam 53. By removing the cover plate 110, the cam follower 70 can be released from the cam as indicated by arrow 120 in Figure 19 so that the image can be removed through a slot at 121 in the direction 122 upwards to enable replacement of the image.

In use, an image substantially as shown in Figures 1 to 13 is formed and mounted as the display element in any of the described embodiments. Operation of the cam and cam follower causes the image to move relative to the lens, thereby creating the illusion of at least one movement of the image as described in Figures 10 to 13.

The display device described provides for the display of sequential images in high quality and can provide a relatively inexpensive advertising and promotional display device showing a short sequence of smoothly moving images. A substantially continuously running motor is provided to drive the image rather than a stepping motor in currently available designs. The invention enables a display device to show sequential images at a widely varying speed and to provide a degree of natural appearance.

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The display device also enables illustrations in substantially 3D due to the multiple views that can be provided. This provides a simple and economical device for demonstrating an object in a multiple view perspective for advertising, promotional and educational purposes. The display device can also be used outdoors, displaying multiple images and short videos due to the weather resistance provided in a preferred embodiment.

Claims (17)

1. A display device for displaying at least two consecutive images to be viewed by a viewer, comprising:
a housing ( 1 ) with at least two wall regions defining a cavity therebetween, at least a part of a wall region being made of a lenticular lens ( 3 ),
at least one carrier ( 9 ) in the cavity, the carrier being designed to receive a substantially planar display element in use,
and a pressure means for urging the display element against the lenticular lens ( 3 ) when a display element is located in the cavity. 2. Display device according to claim 1, characterized in that the pressure means comprises a plurality of rollers ( 8 ) and biasing means for biasing the rollers so that the display element is forced against the lenticular lens ( 3 ). 3. Display device according to claim 1 or 2, characterized in that the pressure means rest on the display element. 4. Display device according to claim 2 or 3, characterized in that a plate ( 5 ) is also provided in the cavity, the pressure means resting on the plate, which in turn rests on the display element. 5. A display device according to claim 3 or 4, characterized in that a substantially transparent retaining sheet is positioned substantially against the side of the lenticular lens ( 3 ) which faces outward with respect to the housing. 6. Display device according to one of the preceding claims, characterized in that at least 15 cylindrical lenses per inch (Lpi) are provided in the lenticular lens ( 3 ). 7. Display device according to claim 6, characterized in that at least 20 cylindrical lenses per inch (Lpi) are provided. 8. Cylindrical lens according to claim 7, characterized in that at least 30 cylindrical lenses per inch (Lpi) are provided. 9. Display device according to one of the preceding claims, characterized in that an adjusting means for moving the lenticular lens ( 3 ) relative to the display element is provided. 10. Display device according to claim 9, characterized in that the adjustment means can be operated from the outside of the housing ( 1 ). 11. A display device according to claim 9 or 10, characterized in that the adjusting means includes a pivot on which the lenticular lens ( 3 ) is mounted and is operable to rotate the lenticular lens ( 3 ) about the pivot. 12. Display device according to any one of the preceding claims, characterized in that a drive means is provided which is operable for a relative movement substantially in the planes thereof between the lenticular lens ( 3 ) and the display element. 13. Display device according to claim 12, characterized in that guide means are provided to maintain the lenticular lens ( 3 ) and the display element in a substantially parallel relationship during a relative movement of the lenticular lens ( 3 ) and the display element. 14. Display device according to any one of the preceding claims, characterized in that the drive means comprises a motor (S 1) and control means are provided to adjust the speed of the motor. 15. Display device according to any one of the preceding claims, characterized in that an adjustment means is provided to enable a substantially parallel arrangement between the display element and the lenticular lens ( 3 ). 16. Display device according to any one of the preceding claims, characterized in that up to twelve consecutive images are visible. 17. Display device according to any one of the preceding claims, characterized in that the images viewed appear in 3D.