Liquid-crystal display with polarizer, and method of making the same

{
  "publication_number": "US4061418A",
  "country": "US",
  "kind": "A",
  "title": "Liquid-crystal display with polarizer, and method of making the same",
  "abstract": "A liquid-crystal display having two carrier plates, between which a liquid crystal material is enclosed in hermetically sealed relation, and which have respective electrode coatings on their inner surfaces, at least one carrier plate having a polarizer disposed on the outer surface thereof, comprising a chemically inert, transparent and optically inactive protective foil and a dichroitic layer disposed between the protective foil and the carrier plate, with the marginal edges of the polarizer being covered with coating means for sealing the dichroitic layer from atmospheric influences, particularly humidity, and method of making the same.",
  "claims": [
    "1. In a liquid-crystal display having two carrier plates between which a liquid crystal material is enclosed in hermetically sealed relation, and having respective electrode coatings on their inner surfaces, the combination of at least one carrier plate having a polarizer disposed on the outer surface thereof, which comprises a chemically inert, transparent and optically inactive protective foil and a dichroic layer disposed between the protective foil and the carrier plate, the marginal edges of the polarizer being covered with coating means for sealing the dichroic layer from atmospheric influences, particularly humidity.",
    "2. A liquid-crystal display according to claim 1, wherein the coating is a lacquer.",
    "3. A liquid-crystal display according to claim 1, wherein the coating is a non-hygroscopic epoxy glue.",
    "4. A liquid-crystal display according to claim 1, wherein the coating is a metal paste.",
    "5. A method of forming a polarizer for a liquid-crystal display having two carrier plates between which a liquid crystal material is enclosed in hermetically sealed relation, and having respective electrode coatings on their inner surfaces, comprising the steps of disposing a dichroic layer on the outer surface of at least one carrier plate, super-imposing a layer of a chemically inert, transparent and optically inactive protective material on said dichroic layer, and covering the marginal edges of the polarizer with a protective coating to seal the dichroic layer from atmospheric influences, particularly humidity.",
    "6. A method according to claim 5, wherein the protective coating is applied in a screen-printing operation.",
    "7. A method according to claim 5, wherein the protective coating is printed on.",
    "8. A method according to claim 5, wherein the protective coating is sprayed on."
  ],
  "description_excerpt": "The invention relates to a liquid-crystal display employing two carrier plates, between which is disposed a liquid-crystal layer which is hermetically sealed therebetwen, with the plates having respective electrode coatings on their inner surfaces, and in which at least one carrier plate has a polarizer disposed on its outer surface comprising a chemically inert, transparent and optically inactive protective foil and a dichroitic layer disposed between the protective foil and the associated carrier plate. Such display structures are known, for example from U.S. Letters Pat. No. 3,731,986. See also Appl. Phys. Lett. Vol. 18, No. 4, Pages 127 and 128, regarding operation of such displays.\n\nTo enable utilization of different field effects, for example the TN effect (twisted nematic), the DAP (deformation of aligned phases), the bistability effect or the so-called guest-host effect, as well as in certain other display principles, it is required or useful, to provide the liquid-crystal cell with at least one polarizer. Usually, the liquid-crystal cell is disposed between two linear polarizers with such polarizers normally containing a dichroitic layer as the polarization-active material, for example a stretched poly-vinyl alcohol, colored with iodine, which is protected from surrounding influences by a protective foil covering layer composed of a chemically inert, transparent and optically inactive materials, both layers are integrated with the supporting plate to form a multi-layer structure, preferably with a suitable glue inserted between the dichroitic layer and the plate.",
  "cpc": [
    "G02F 1/133528",
    "Y10S 359/90"
  ],
  "ipc": [
    "G02F 1/1335",
    "G09F 9/00"
  ],
  "assignees": [
    "Siemens AG"
  ],
  "inventors": [
    "Rudolf Poensgen"
  ],
  "filing_date": "1976-09-30",
  "publication_date": "1977-12-06",
  "grant_date": "1977-12-06",
  "priority_date": "1975-10-07",
  "application_number": "US-72829476-A",
  "family_id": "5958561",
  "cited_by_count": 16,
  "citations": [
    "US3859131A",
    "US3869196A",
    "US4025688A"
  ]
}