GB2149177A

GB2149177A - Indicator system

Info

Publication number: GB2149177A
Application number: GB08328943A
Authority: GB
Inventors: Clifford Hardcastle
Original assignee: Individual
Current assignee: Individual
Priority date: 1983-10-29
Filing date: 1983-10-29
Publication date: 1985-06-05
Also published as: GB8328943D0

Abstract

A circular housing 10 is provided with a front layer 11 and rear layer 12 of polarised material. Relative rotation of these layers is effected by coils 16 in combination with spaced magnets 21A-21H, so that stepped movement can be provided to give intermediate shades between light and dark. A matrix of indicators allows larger and more complex indicia to be provided under computer control. Alternatively, electrostatic excitation may be employed to cause the rotation. In Fig. 1, a reflective surface 13 may be coloured or fluorescent. In Fig. 2, the rotary layer 12 is without a spindle and the screen 20 may be reflective or of transparent coloured material to allow a back-lit system. Letters or logos could be carried on the screen. <IMAGE>

Description

SPECIFICATION Indicator system The invention relates to a system for indicating or display purposes.

According to the invention there is provided an indicator system comprising first and second layers of a plane polarised material and means for moving the material layers relative to each other whereby the planes of polarisation are altered to vary the light transmission characteristics.

Preferably the rotation can be effected in steps to graduate the light transmisson.

The means for moving the material may comprise electro-magnet or electrostatic actuators.

The invention will now be described by way of example with reference to the accompanying drawing in which:- Figure 1 shows one embodiment of the present invention, Figure 2 shows a second embodiment, Figure 3 shows a matrix configuration and Figure 4 shows a large display under computer control.

Fig. 1 shows one embodiment of the system comprising a circular housing 10 with a front screen 11 of polarised material. A second disc-like layer 1 2 of polarised material is rotatably mounted on a spindle 1 4 itself mounted on bearing 1 8. Beneath this material is a reflecting surface 1 3. The rotation of the disc is determined by electrical signals applied to coils 16. Magnetic material 19 carried by the rotatable disc portion assists in the rotation depending on the relative polarity. As the disc rotates, the indicator will change from light to dark or vice versa dependent on the relative planes of polarisation of the material.

The reflecting material may be coloured or be fluorescent to show a change in colour.

In the Fig. 2 arrangement the moveable portion is mounted without a spindle to allow unrestricted viewing of the screen surface 20.

Whilst the screen may be reflective, alternatively, it may be of a transparent coloured material to allow a back-lit system to be provided. A number of magnets 21A to 21 H may be provided to allow stepped rotation to be effected using pulse signals as the input to coils 1 6. This then provides an indicator or display with the option of intermediate shades between light and dark. Thus shades of grey could be provided for example. Letters, logos or other matter could be carried on the screen if desired, as illustrated by the letter H shown.

The rotatable portion could alternatively be of a drum-like configuration and the magnets could be fabricated using magnetic ink or ferrite material for example.

An alternative system would employ electrostatic operation whereby rotation would depend on electrostatic fields generated from incoming signals.

Although the indicator can be fabricated and used as a single unit, each unit can form part of a larger display matrix 30 (e.g. 7 x 5) as illustrated in Fig. 3. By selecting various ones of the display units, letters or words could be generated.

When very large matrices 31 are employed these may be driven by a computer 32 via an interface 33 to provide message display for example. Such a system when employing the partial rotational aspects will allow picture scenes to be generated due to the shades of grey or other colours employed.

Although the embodiments have used a single rotational layer, the other polarised layer may alternatively or additionally rotate.

1. An indicator system comprising first and second layers of a plane polarised material and actuator means for moving the material layers relative to each other in response to electrical signals whereby the planes of polarisation are altered to vary the light transmission characteristics.

2. A system as claimed in claim 1, wherein the actuator means is adapted to effect relative rotation of the layers.

3. A system as claimed in claim 2, wherein the actuator means is arranged to be actuated so as to cause rotation in steps to graduate the light transmission.

4. A system as claimed in claim 2 or 3, wherein at least one of said first and second layers is disc or drum shaped.

5. A system as claimed in claim 2, 3 or 4, wherein a spindle is provided to allow a disc shaped second layer attached thereto to be rotated.

6. A system as claimed in any one of claims 1 to 5, wherein the actuator means is electromagnetically operable, 7. A system as claimed in any one of claims 1 to 5, wherein the actuator means is electrostatically operable.

8. A system as claimed in any preceding claim including a third layer of a screen material selectively visible in dependence on the operation of said actuator means.

9. A system as claimed in claim 8, wherein the screen is of a reflective material.

1 0. A system as claimed in claim 8, wherein the screen is of a transparent material to facilitate back lighting.

11. A system as claimed in any preceding claim wherein a matrix of individual indicators is provided to allow indicia to be formed from a combination thereof.

1 2. A system as claimed in claim 11, including drive means for automatically selecting the correct combination of indicators in the matrix.

1 3. A system as claimed in claim 12, wherein the drive means includes a computer

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Indicator system The invention relates to a system for indicating or display purposes. According to the invention there is provided an indicator system comprising first and second layers of a plane polarised material and means for moving the material layers relative to each other whereby the planes of polarisation are altered to vary the light transmission characteristics. Preferably the rotation can be effected in steps to graduate the light transmisson. The means for moving the material may comprise electro-magnet or electrostatic actuators. The invention will now be described by way of example with reference to the accompanying drawing in which:- Figure 1 shows one embodiment of the present invention, Figure 2 shows a second embodiment, Figure 3 shows a matrix configuration and Figure 4 shows a large display under computer control. Fig. 1 shows one embodiment of the system comprising a circular housing 10 with a front screen 11 of polarised material. A second disc-like layer 1 2 of polarised material is rotatably mounted on a spindle 1 4 itself mounted on bearing 1 8. Beneath this material is a reflecting surface 1 3. The rotation of the disc is determined by electrical signals applied to coils 16. Magnetic material 19 carried by the rotatable disc portion assists in the rotation depending on the relative polarity. As the disc rotates, the indicator will change from light to dark or vice versa dependent on the relative planes of polarisation of the material. The reflecting material may be coloured or be fluorescent to show a change in colour. In the Fig. 2 arrangement the moveable portion is mounted without a spindle to allow unrestricted viewing of the screen surface 20. Whilst the screen may be reflective, alternatively, it may be of a transparent coloured material to allow a back-lit system to be provided. A number of magnets 21A to 21 H may be provided to allow stepped rotation to be effected using pulse signals as the input to coils 1 6. This then provides an indicator or display with the option of intermediate shades between light and dark. Thus shades of grey could be provided for example. Letters, logos or other matter could be carried on the screen if desired, as illustrated by the letter H shown. The rotatable portion could alternatively be of a drum-like configuration and the magnets could be fabricated using magnetic ink or ferrite material for example. An alternative system would employ electrostatic operation whereby rotation would depend on electrostatic fields generated from incoming signals. Although the indicator can be fabricated and used as a single unit, each unit can form part of a larger display matrix 30 (e.g. 7 x 5) as illustrated in Fig. 3. By selecting various ones of the display units, letters or words could be generated. When very large matrices 31 are employed these may be driven by a computer 32 via an interface 33 to provide message display for example. Such a system when employing the partial rotational aspects will allow picture scenes to be generated due to the shades of grey or other colours employed. Although the embodiments have used a single rotational layer, the other polarised layer may alternatively or additionally rotate. CLAIMS

6. A system as claimed in any one of claims 1 to 5, wherein the actuator means is electromagnetically operable,

7. A system as claimed in any one of claims 1 to 5, wherein the actuator means is electrostatically operable.

1 3. A system as claimed in claim 12, wherein the drive means includes a computer and an associated interface.

14. An indicator system substantially as described herein with reference to any one of the example illustrated in the accompanying drawings.