Liquid crystal display device with improved contact means

• US 3,914,021 A
• Filed: 05/03/1974
• Issued: 10/21/1975
• Est. Priority Date: 07/09/1971
• Status: Expired due to Term

• Current Assignee: Izuhiko Nishimura
• Original Assignee: Izuhiko Nishimura
• Inventors: Nishimura, Izuhiko
• Primary Examiner(s): Bauer, Edward S.
• Application Number:
  US05/466,947
• Time in Patent Office: 536 Days
• Field of Search: 350/16LC 339/17CF,17L
• US Class Current: 349/58
• CPC Class Codes: G02F 1/1345 Conductors connecting electrodes to cell terminals
• CPC Class Codes: G04G 17/06 Electric connectors, e.g. conductive elastomers

Abstract

In a liquid crystal display device having opposing plates, the plates are so disposed that at least one edge of one of the plates extends beyond an edge of the other. The exposed edge has contact areas thereon connected to conductive areas in the display portion of the device. A frame holds the plates in position with respect to each other and the frame has mounted thereon resilient conductive fingers so positioned that each one makes contact with a separate contact area on the extended edge, the contact being restricted in area to increase the contact pressure. These conductive fingers are resilient and provide a convenient means for removably connecting each of the contact areas to an outside voltage source. Wiping contact between the fingers and the contact area may be provided.

Claims

1. In a liquid crystal display device comprising opposing insulating plates and a spacer defining a chamber containing liquid crystals, at least one conductive area on the interior of each of said plates and within the display region of said device, a separate contact area proximate an edge of at least one of said plates and exterior to said spacer, said contact areas corresponding in number to the number of conductive areas on said plates, and a strip lead connecting each conductive area to a corresponding contact area, the improvement wherein said insulating plates are of such size and are so positioned that at least one edge of one plate having contact areas proximate said edge projects beyond an edge of the other of said opposing plates, thereby making the contact areas proximate said extended edge readily accessible for connection to an outside source of voltage, and comprising a plurality of resilient conductive fingers for making contact with each of said contact areas and mounting means holding said fingers as a unit and shaped for holding said fIngers firmly in mechanical contact with said contact areas when said mounting means is brought into registry with said plates, said fingers being so shaped and so disposed in said mounting means that each of said fingers makes contact with a corresponding contact area under a sufficiently high bising spring force and over a sufficiently restricted region so that contact pressure in said restricted region is high enough to ensure good electrical contact.

2. A liquid crystal display device as defined in claim 1, wherein said restricted region corresponds to the area of an end of said finger.

3. A liquid crystal display device as defined in claim 1, wherein said restricted region corresponds to an edge of said finger.

4. A liquid crystal display device as defined in claim 1, wherein said fingers are so shaped that as said mounting means is brought into registry with said plates, wiping contact is made between said fingers and said contact areas.

5. A liquid crystal display device as defined in claim 1, wherein each of said opposing plates has at least one edge having contact areas proximate thereto and extending beyond an edge of the opposing plate and said mounting means has resilient fingers mounted thereon making electrical contact with each contact area on each of said opposing plates.

6. A liquid crystal display device as defined in claim 1, wherein said contact areas are covered with a metal of high tarnish-resistance chosen from the group consisting of silver and gold.

7. A liquid crystal display device as defined in claim 1, wherein the conductive areas on one of said opposing plates are segmented and grouped so as to be able to display at least one character, the conductive areas on the other plate are of such size and so located that each conductive area on said other plate opposes the group of segments of a single character, each said other plate has contact areas equal in number to the number of conductive areas and conductive-film leads from each of said conductive areas to said contact areas, said one plate has a contact area directly opposite each of said contact areas on said other plates, connecting means makes electrical contact between each of said contact areas on said other plate and the opposite contact area on said one plate, said one plate has at least one edge extending beyond an edge of said other plate, said one plate has additional contact areas corresponding in number to said opposite contact areas on said extended edge of said one plate, said one plate has conductive-film leads connecting each of said opposite contact areas to a corresponding additional contact, and said mounting means has flexible contact fingers thereon, said fingers corresponding in number to the total number of contact areas on said extended edge of said one plate, thereby making it possible to connect all of said conductive areas on both plates to an outside voltage source through the use of fingers making contact with contact areas on said one plate only.

8. A liquid crystal display device as defined in claim 7, wherein said connecting means is a conductive, resilient metal spring.

9. A liquid crystal display device as defined in claim 7, wherein said connecting means is a conductive, resilient organic resin.

10. A liquid crystal display device as defined in claim 1, wherein said mounting means holds said plates together.