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US 5,295,837 AGranted
Magnetic visual display
AssigneeThe Ohio Art Company
InventorsMichael Gilano, Michael A. Gilano, Gordon B. Langford
Life of this patent
Estimating the term…
Abstract
An apparatus for providing a magnetic visual display in which a magnetic field is exposed to a dispersion medium sealed between two surfaces and having distributed therein randomly-oriented magnetically-active flakes, thereby causing alignment of a portion of the flakes and allowing transmission of light through the dispersion medium in the region of the aligned flakes to form an image by the contrast between the areas of aligned and randomly-oriented flakes. The contrast may be enhanced by a light source on the opposite side of the device from the viewer. The image may be colored by coloring either of the surfaces, the dispersion medium, the flakes or the light from the light source.
Claims48
A magnetic marking apparatus, comprising:
- a first non-opaque surface;
- a second surface spaced opposite from said first surface;
- a non-opaque dispersion medium contained between said first and second surfaces;
- a plurality of randomly oriented, magnetically active flakes in said dispersion medium, said flakes being dispersed such that said randomly oriented flakes produce a substantially uniform background when viewed through said first surface;
- a permanent magnet for aligning said flakes in the dispersion medium proximate said magnet upon the application of said magnet to one of said surfaces, whereupon said portion of said dispersion medium containing aligned flakes allows light transmission therethrough;
- and
- wherein the spacing between said first and second surfaces is selected so that light passing through said first surface and said portion of said dispersion medium containing said aligned flakes is transmitted to said second surface and creates an image formed by the contrast between said second surface as viewed through said first surface and said generally uniform background.
4 more elements
A magnetic marking apparatus, comprising:
- a first non-opaque surface;
- a second colored surface spaced opposite said first surface;
- a non-opaque dispersion medium contained between said first and second surfaces;
- a plurality of randomly oriented, magnetically active flakes, in said dispersion medium, said flakes being dispersed such that said flakes produce a substantially uniform background when viewed through said first surface;
- a permanent magnet for aligning said flakes in the dispersion medium proximate said magnet upon the application of said magnet to one of said surfaces, whereupon said portion of said dispersion medium containing aligned flakes allows light transmission therethrough;
- and
- wherein the spacing between said first and second surfaces is selected so that light passing through said first surface and said portion of said dispersion medium containing said aligned flakes is transmitted to said second surface, thereby affording a view of said second surface through said portion of said dispersion medium containing aligned flakes and creating an image formed by the contrast between said generally uniform background and said second surface view.
4 more elements
A magnetic marking apparatus, comprising:
- a first non-opaque surface;
- a second surface spaced opposite from said first surface;
- a separation element interposed between said first and second surfaces;
- a non-opaque dispersion medium contained between said first and second surfaces;
- a plurality of randomly oriented, magnetically active flakes in said dispersion medium, said flakes being dispersed such that said flakes produce a substantially uniform background when viewed through said first surface;
- a permanent magnet for aligning said flakes in the dispersion medium proximate said magnet upon the application of said magnet to one of said surfaces, whereupon said portion of said dispersion medium containing aligned flakes allows light transmission therethrough;
- and
- wherein the spacing between said first and second surfaces is selected so that said portion of said dispersion medium containing aligned flakes extends completely between said surfaces, thereby allowing light passing through said first surface and said portion of said dispersion medium containing said aligned flakes to be transmitted to said second surface.
5 more elements
A magnetic marking apparatus, comprising:
- a sealed housing, having:
- a first non-opaque surface;
- a second surface spaced opposite from said first surface, said second surface being colored;
- and
- a separation element interposed between said first and second surfaces;
- a non-opaque dispersion medium having a thixotropic agent and generally filling said sealed housing and having disposed therein a plurality of randomly oriented, magnetically active flakes, said flakes having an aspect ratio having at least two of the height, length or width measurements of about 5:1 or greater, said flakes being dispersed such that said randomly oriented flakes produce a substantially uniform background when viewed through said first surface;
- a permanent magnet for aligning said flakes in the dispersion medium proximate said magnet upon the application of said magnet to one of said surfaces, whereupon said portion of said dispersion medium containing aligned flakes allows light transmission therethrough;
- and
- wherein the spacing between said first and second surfaces is selected so that light passing through said first surface and said portion of said dispersion medium containing said aligned flakes is transmitted to said second surface, thereby affording a view of said second surface through said portion of said dispersion medium containing aligned flakes and creating a colored image formed by the contrast between said generally uniform background and said second surface view.
6 more elements
A magnetic marking apparatus comprising:
- a front non-opaque surface;
- a rear surface spaced opposite said front surface;
- a non-opaque dispersion medium contained between said surfaces;
- a plurality of randomly oriented, magnetically active flakes in said dispersion medium, said flakes being dispersed such that light passing through said front surface and striking said randomly oriented flakes produces a substantially uniform background as viewed through said front surface;
- and
- a permanent magnet for aligning said flakes in the dispersion medium proximate said magnet upon the application of said magnet to one of said surfaces, whereupon said portion of said dispersion medium containing aligned flakes allows light transmission therethrough;
- and
- wherein the spacing between said front and back surfaces is selected so that light passing through said front surface and said portion of said dispersion medium containing said aligned flakes is transmitted to said rear surface and wherein one of said back surface, dispersion medium or flakes is colored.
5 more elements
A magnetic marking apparatus, comprising:
- first and second spaced, non-opaque surfaces;
- a non-opaque dispersion medium contained between said first and second surfaces;
- a plurality of randomly oriented, magnetically active flakes in said dispersion medium, said flakes being dispersed such that said randomly oriented flakes produce a substantially uniform background when viewed through said first surface and such that light passing through said second surface and striking said randomly oriented flakes is prevented from reaching said first surface;
- a permanent magnet for aligning said flakes in the dispersion medium proximate said magnet upon the application of said magnet to one of said surfaces, whereupon said portion of said dispersion medium containing aligned flakes allows light transmission therethrough;
- and
- a light source proximate said second surface for directing light through said portion of dispersion medium containing aligned flakes and said first surface, said light creating an image viewable through said first surface by contrasting with said generally uniform background.
3 more elements
A magnetic marking apparatus, comprising:
- a first non-opaque surface;
- a second surface spaced opposite from said first surface;
- a non-opaque dispersion medium contained between said first and second surfaces;
- a plurality of randomly oriented, magnetically active flakes dispersed in said dispersion medium in an amount sufficient to provide opacity when randomly oriented;
- a permanent magnet for applying to one of said surfaces to align said flakes in a portion of said dispersion medium proximate said magnet;
- and
- wherein the distance between said first and second surfaces, the thickness and amount of said flakes, the intensity of said magnet, and the viscosity of said dispersion medium are selected so that said portion of said dispersion medium containing aligned flakes extends completely between said surfaces, thereby allowing light passing through said first surface and said portion of said dispersion medium containing said aligned flakes to be transmitted to said second surface.
4 more elements
A magnetic marking apparatus, comprising:
- first and second planar, parallel non-opaque surfaces;
- a housing supporting said non-opaque surfaces and, along with said non-opaque surfaces, defining a sealed interior space;
- a dispersion medium sealed in said interior space;
- a plurality of magnetically active particles dispersed within said dispersion medium;
- and
- a permanent drawing magnet outside said interior space having a magnetic field;
- wherein said non-opaque surfaces are spaced close enough so that the application of said drawing magnet to one of said surfaces causes movement of said particles throughout the dispersion medium proximate said drawing magnet and between said first and second non-opaque surfaces, so as to create an image on said first and second non-opaque surfaces.
4 more elements
A magnetic marking apparatus, comprising:
- first and second spaced, planar, parallel non-opaque surfaces;
- a housing supporting said non-opaque surfaces and, along with said non-opaque surfaces, defining a sealed interior space;
- a dispersion medium sealed in said interior space;
- a plurality of magnetically active particles dispersed within said dispersion medium;
- a permanent drawing magnet outside said interior space having a magnetic field sufficient that application of said drawing magnet to a selected point on said first non-opaque surface causes movement of said particles in a portion of said dispersion medium proximate said point and extending between said first and second non-opaque surfaces, whereby selective application of said drawing magnet to said first non-opaque surface causes movement of a selected portion of said particles and results in the creation of an image viewable through said first non-opaque surface;
- and
- a permanent erasing magnet outside said interior space having a magnetic field sufficient to cause movement of said particles upon application of said magnet to said non-opaque surfaces, whereby selective application of said erasing magnet to said second non-opaque surface causes movement of said selected portion of said particles and results in the erasure of said image.
4 more elements
A magnetic marking apparatus, comprising:
- first and second spaced, planar, parallel non-opaque surfaces;
- a housing supporting said non-opaque surfaces and, along with said non-opaque surfaces, defining a sealed interior space;
- a dispersion medium sealed in said interior space;
- a plurality of magnetically active particles dispersed within said dispersion medium;
- a permanent drawing magnet outside said interior space having a magnetic field sufficient that application of said drawing magnet to a selected point on said first non-opaque surface causes movement of said particles in a portion of said dispersion medium proximate said point and extending between said first and second non-opaque surfaces, whereby selective application of said drawing magnet to said first non-opaque surface causes movement of a selected portion of said particles and results in the creation of a first image viewable through said first non-opaque surface and a second image viewable through said second non-opaque surface.
2 more elements
Dependencies are inferred from the claim text.