Particulate spacers for touch sensitive overlay panel applications
First Claim
1. An apparatus in which two closely spaced apart normally parallel layers of material are positioned to be moved closer relative to one another in order to establish local contact therebetween only when and where one of the normally parallel layers is subjected to the action of an external force, comprising:
- a first layer of a first transparent material comprising a first surface and a parallel second surface;
a second layer of a second transparent material comprising a third surface and a parallel fourth surface, said third surface being positioned adjacent and parallel to said second surface of said first layer;
optically-transparent, randomly non-uniformed sized, substantially similarly shaped particles comprising a third material which are randomly distributed in a predetermined density between said first and second layers and adhered to at least one of said second and third surfaces, wherein a largest-sized portion of said particles are in simultaneous contact with said second and third surfaces and said first and second layers are maintained separate at a corresponding distance apart in the absence of an external force applied onto one of said layers such that said adjacent surfaces are placed in contact with one another when and where said external force is applied.
2 Assignments
0 Petitions
Accused Products
Abstract
Fine particles, of predetermined composition and sized to be within a predetermined size range, are deposited on, and thereafter adhere in random distribution to, one of two adjacent surfaces, serving to keep the surfaces uniformly spaced apart except when an external force causes them to make local contact. The particles are conveniently applied in the form of a spray of a suspension of particles and a fluid carrier material, preferably water with alumina particles, or an aqueous solution of a chloride salt of an alkaline earth metal such as calcium, potassium or sodium when small glass beads are used as the particles. Brown alumina particles (approximately 96% Al2 O3) in the size range 3-50 microns, so utilized, are found well suited as parallel surface spacers in optically transparent touch sensitive overlay (TSO) panels. Particle distribution densities in the range 300-1,000 particles per inch are satisfactory for TSO panels, with the higher particle density requiring a higher actuation pressure to be applied.
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Citations
27 Claims
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1. An apparatus in which two closely spaced apart normally parallel layers of material are positioned to be moved closer relative to one another in order to establish local contact therebetween only when and where one of the normally parallel layers is subjected to the action of an external force, comprising:
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a first layer of a first transparent material comprising a first surface and a parallel second surface; a second layer of a second transparent material comprising a third surface and a parallel fourth surface, said third surface being positioned adjacent and parallel to said second surface of said first layer; optically-transparent, randomly non-uniformed sized, substantially similarly shaped particles comprising a third material which are randomly distributed in a predetermined density between said first and second layers and adhered to at least one of said second and third surfaces, wherein a largest-sized portion of said particles are in simultaneous contact with said second and third surfaces and said first and second layers are maintained separate at a corresponding distance apart in the absence of an external force applied onto one of said layers such that said adjacent surfaces are placed in contact with one another when and where said external force is applied. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
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9. An apparatus in which two closely spaced-apart light-transmitting normally parallel layers are positioned to be moved closer to one another to establish local contact therebetween under the action of an external force, comprising:
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a first layer of a first optically-transparent material comprising a first surface and a parallel second surface, wherein said first surface receives incident light and transmits a first portion of said light through said first layer and out through said second surface; a second layer of a second optically-transparent material comprising a third surface and a parallel fourth surface, said third surface being positioned adjacent to said second surface; and optically-transparent, randomly non-uniformly sized, substantially similarly shaped particles comprising a third material which are randomly distributed in a predetermined density between said first and second layers and adhered to at least one of said second and third surfaces, wherein a largest-sized portion if said particles are in simultaneous contact with said second and third surfaces and said first and second layers are maintained separate at a corresponding distance apart in the absence of an external force applied onto one of said layers such that said adjacent surfaces are placed in contact with one another when and where said external force is applied, the minimum separation between said adjacent surfaces at any location being determined in the absence of an external force by the smallest of said particles at that location. - View Dependent Claims (10, 11, 12, 13, 14, 15, 16, 17)
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18. An apparatus in which two closely space-apart, light-transmitting, electrically-conducting, normally-parallel layers of transparent material are positioned to be moved closer relative to one another to establish local contact therebetween under the action of an external force, comprising:
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a first layer of a first electrically non-conductive optically-transparent material comprising a first surface and a parallel second surface; a first electrically-conductive material of optically-transparent thickness which is attached to said second surface in a first set of zones of predetermined shape, size and orientation; a second layer of a second electrically non-conductive optically-transparent material comprising a third surface and a parallel fourth surface; a second electrically-conductive material of optically-transparent thickness which is attached to said third surface in a second set of zones of predetermined shape, size and orientation, said first and second sets of electrically-conductive zones being positioned adjacent and normally parallel to one another; and electrically non-conductive, randomly non-uniformly sized, substantially similarly shaped particles comprising a third material which are randomly distributed at a predetermined density on said second set of zones, wherein a largest-sized portion of said particles are in simultaneous contact with at least one zone from each of said first and second sets and said sets of zones are thereby maintained separate at a corresponding distance apart in the absence of an external force applied onto one of said layers such that at least one zone each from each of said sets of zones are placed in electrical contact with one another where said external force is applied, the minimum separation between said adjacent surfaces at any location being determined in the absence of an external force by the smallest of said particles at that location. - View Dependent Claims (19, 20, 21, 22, 23, 24, 25, 26, 27)
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Specification