WO1997025701A1

WO1997025701A1 - Display panel

Info

Publication number: WO1997025701A1
Application number: PCT/NL1996/000014
Authority: WO
Inventors: Frank Alexander Van Den Bovenkamp
Original assignee: Den Bovenkamp Frank Alexander
Priority date: 1996-01-08
Filing date: 1996-01-08
Publication date: 1997-07-17
Also published as: AU4634596A

Abstract

The invention relates to a display panel with a plurality of picture elements arranged in rows and columns and movable covering bodies placed on the visual side of the picture elements. For each picture element is herein arranged at least one separate covering body which is movable between a position revealing its associated picture element and a position covering the picture element. With such a panel messages and images can be displayed with great accuracy in different shades of grey. For each picture element a number of covering bodies can be arranged embodied in different colours, whereby coloured images can also be displayed.

Description

DISPLAY PANEL

The present invention relates to a display panel with a plurality of picture elements arranged in rows and columns and at least one movable covering body placed on the visible side of the picture elements. Such a display panel is known for instance from O-A-80/02210. In the known display panel letters, numerals and/or figures are displayed by moving the covering body, which has a grid of openings, relative to the picture elements such that determined picture elements come to lie in register with the openings in the covering body and thus become visible.

This known display panel has the great drawback that the letters, numerals and/or figures for display therewith are determined by the placing of the picture elements and the form of the grid of openings in the covering body; as a result only a limited variety of images can be displayed.

Other known display panels for instance comprise picture elements in the form of discs or cubes which are rotatable on a shaft and the faces of which are differently coloured. In these display panels each pic¬ ture element can take on two or more different colours, and a great variety of letters, numerals and/or figures can be displayed by actuating the picture elements sepa- rately.

These display panels have the drawback however that the size of the picture elements determines the definition of the displayed picture and this can only be reduced at the cost of a very great structural complexity and a high energy consumption. The picture of such a display panel is thus inevitably rather grainy.

The invention therefore has for its object to provide a display panel with which a great variety of letters, numerals and/or figures can be very sharply dis- played in simple manner and at limited cost. This is achieved according to the invention in that at least one separate covering body is provided for each picture element.

Each covering body is preferably movable between a first position which substantially fully reveals its associated picture element and a second position which substantially fully covers the picture element. By moving the covering bodies of some picture elements to an intermediate position located between these two extreme positions larger and smaller picture elements are as it were created, whereby "shades of grey" can be generated in similar manner as with screen printed photos.

When for each picture element a number of covering bodies embodied in different colours are provided, "mixed colours" can as it were be chosen for the picture elements.

A very distinctive display panel with italics is obtained when the picture elements are diamond-shaped. Mentioned and other features of the display panel according to the invention are elucidated hereinbelow on the basis of an embodiment, wherein reference is made to the annexed drawing in which corresponding parts are designated with corresponding reference numerals and in which: fig. 1 shows a partly cut-away perspective view of a starting situation of the display panel according to the invention, fig. 2 is a partly cut-away perspective view of the display panel according to the invention in use, fig. 3 is a perspective detailed view in section of the display panel according to the invention, fig. 4 is a longitudinal section of a part of the display panel, fig. 5 is a partly cut-away perspective view with exploded parts of a detail of an alternative embodiment of the display panel according to the invention, and fig. 6 is a partly cut-away perspective view of the embodiment shown in fig. 5 in the assembled state.

A display panel (fig. 1) comprises a plurality of picture elements 2 arranged in rows and columns and a plurality of movable covering bodies 3 which are not visible in the shown starting situation and which are placed on the visible side of the picture elements 2. Each covering body 3 is movable between the shown first position, in which it substantially fully reveals its associated picture element 2 and a second position in which the covering body 3 substantially fully covers the picture element. The covering bodies 3 are moved in the direction of the rows indicated by the arrow by means of a control device 4, which comprises a carriage 5 movable along the rear side of display panel 1 directed away from the visual side, on which carriage an actuating arm 6 is arranged for each row of picture elements 2. Carriage 5 is driven by a motor 7. The movement of carriage 5 and actuating arms 6 is controlled by electronic control means 8, which may for instance take the form of a computer.

By causing carriage 5 to move along from right to left behind display panel 1 and by moving actuating arms 6 under the influence of control means 8 such that particular chosen covering bodies 3 are moved from their first revealing position to their second covering posi¬ tion, or to an intermediate position, letters, numerals and/or figures can be formed on display panel (fig. 2) . In the embodiment shown here, the electronic control means 8 take the form of a simply displaceable control unit which can be programmed using a computer.

The picture elements 2 are formed by partly overlapping picture bodies 9 which are arranged at an angle to the principal plane of display panel l (fig. 3) . Each row of picture bodies 9 is received between two rails 10, and each rail 10 has openings 11 arranged at regular mutual distances into which engage protrusions 12 of picture bodies 9. The covering bodies 3 are arranged slidably between mutually adjacent picture bodies 9. Each covering body 3 has an end 13 which is bent toward the visible side of display panel 1 and which serves as stop and which rests in the revealing first position against the extremity of a picture body 9. On the rear side of display panel 1 each covering body 3 has a bent end 14 on which engage the actuating arms 6 of the control device 4 movable in the directions D₁ and D₂. The actuating arms 6 are moved by electromagnets 15. The picture elements 2 are protected from outside influences by a transparent plate 16 arranged on the visible side of display panel 1.

During the movement of carriage 5 in the direction Ω_χ or D₂ (fig. 4) the electromagnet 15 is normally energized and holds the actuating arm 6 in the retracted position shown in full lines, in which it does not come in engagement with the bent ends 14 of covering bodies 3. Under the influence of the control means 8 (not shown here) the energizing of electromagnet 15 can be switched off, whereby the actuating arm 6, which is manufactured from a resilient material, assumes the protruding position shown in dashed lines. In this position the actuating arm 6' engages onto the bent end 14 of covering body 3, and covering body 3 is moved along in the direction D_ι or D.. The movement of covering body 3 is bounded in that one of its bent ends 13,14 comes into engagement with an extremity of a picture body 9. The movement of covering body 3 can be interrupted at any desired moment by energizing the electromagnet 15, whereby actuating arm 6 is retracted. The covering body is provided with two angled edges 17, 18, which slide along the mutually adjacent picture bodies 9, whereby covering body 3 is immediately slowed down when the actuating arm 6 is no longer in engagement with its bent end 14. In this manner the displacement of covering body 3 can be precisely controlled and different "shades of grey" can be formed by carrying covering body 3 to a random position located between the first and the second position. In addition to a monochrome display panel 1, wherein the picture bodies 9 have a determined colour and the covering bodies 3 another contrasting colour, it is also possible to form a colour display panel 1 by arranging in front of each picture element 2 a number of covering bodies 3a, 3b, 3c embodied in different colours (fig. 5) . The covering bodies 3a, 3b, 3c are again arranged slidably between two picture bodies 9, and their portion with the bent end 14a, 14b, 14c which is covered by the foremost picture body 9 is partly cut away in order to prevent the separately movable covering bodies 3a, 3b, 3c carrying each other along in their movement. The three covering bodies 3a, 3b, 3c of each row of picture elements 2 are separately controlled by actuating arms 6a, 6b, 6c (not shown) , and are provided with friction bodies 19a, 19b, 19c which have the same function as the angled edges 17, 18 of the above described monochrome panel.

By partly sliding all the different covering bodies 3a, 3b, 3c in front of their associated picture body 9, the impression is created at a distance from the display panel l that the thus formed picture element 2 has a "mixed colour" (fig. 6) .

The display panel 1 according to the invention makes it possible to build up in simple manner a picture which is focussed and displays different "shades of grey" or even "mixed colours". The number of possible "mixed colours" is only limited by the chosen number of covering bodies in different colours. By embodying the picture elements in diamond shape it is possible to depict italics on the display panel, whereby a displayed message becomes extra noticeable. Furthermore, the display panel according to the invention has only a small power consumption.

Claims

1. Display panel with a plurality of picture elements arranged in rows and columns and at least one movable covering body placed on the visible side of the picture elements, characterized in that at least one separate covering body (3) is provided for each picture element (2) .

2. Display panel as claimed in claim 1, characterized in that each covering body (3) is movable between a first position which substantially fully reveals its associated picture element (2) and a second position which substantially fully covers the picture element (2) .

3. Display panel as claimed in claim 1 or 2, characterized in that the covering bodies (3) are displaceable in the row direction (D_χ,D₂) .

4. Display panel as claimed in any of the foregoing claims, characterized in that for each picture element (2) are provided a number of covering bodies (3a, 3b, 3c) embodied in different colours.

5. Display panel as claimed in any of the foregoing claims, characterized in that the picture elements (2) take the form of partly overlapping picture bodies (9) which are arranged at an angle to the principal plane of the panel (1) and the covering bodies (3) are arranged in each case for sliding between mutually adjacent picture bodies (9) .

6. Display panel as claimed in claim 5, characterized in that each row of picture bodies (9) is received between two rails (10) , each of which has openings 11 into which engage protrusions (12) of said picture bodies (9) .

7. Display panel as claimed in any of the foregoing claims, characterized in that the picture elements (2) are diamond-shaped.