{
  "patent_number": "US 2297691",
  "country": "US",
  "title": "Chester Carlson's Original Xerography Patent",
  "original_title": "Electrophotography",
  "summary": "Chester Carlson's 1942 patent for xerography, the dry copying process that became the foundation for Xerox machines.",
  "what_it_does": "This patent describes the fundamental process of xerography, a method for making dry copies of documents. It involves charging a surface with static electricity, exposing it to an image to create an electrostatic latent image, dusting the charged surface with a dry powder (toner), transferring that powder to paper, and then fusing the powder to make the image permanent. The core idea is using static electricity to attract toner particles to form an image, which is then heated to create a lasting copy.",
  "what_it_does_not_cover": [
    "Does not cover wet copying processes",
    "Does not cover processes that use liquid developers instead of dry powder",
    "Does not cover methods that do not involve an electrostatic latent image",
    "Does not cover processes that do not use heat to fuse the toner",
    "Does not cover digital scanning or printing technologies"
  ],
  "filed": "1939-04-04",
  "granted": "1942-10-06",
  "expires": "1959-10-06",
  "status": "expired",
  "holder": "Individual",
  "holder_url": "https://patentbrief.org/company/individual",
  "inventors": [
    {
      "name": "Chester F Carlson",
      "url": "https://patentbrief.org/inventor/chester-f-carlson"
    }
  ],
  "times_cited": 737,
  "tags": [
    "consumer_electronics",
    "software",
    "semiconductors",
    "materials"
  ],
  "abstract": null,
  "url": "https://patentbrief.org/patent/us/2297691/xerography-electrophotography-photocopier",
  "markdown_url": "https://patentbrief.org/patent/us/2297691/xerography-electrophotography-photocopier/md",
  "google_patents_url": "https://patents.google.com/patent/US2297691",
  "relatedPatents": [
    {
      "patentNumber": "3867571",
      "countryCode": "US",
      "title": "How Laser Printers Use Rotating Mirrors to Write Information",
      "url": "https://patentbrief.org/patent/us/3867571/laser-printer-starkweather"
    },
    {
      "patentNumber": "4131919",
      "countryCode": "US",
      "title": "The First Digital Camera's Core Technology",
      "url": "https://patentbrief.org/patent/us/4131919/digital-camera-electronic-still"
    },
    {
      "patentNumber": "5961804",
      "countryCode": "US",
      "title": "Tiny Capsules for Electronic Paper Displays",
      "url": "https://patentbrief.org/patent/us/5961804/e-ink-electronic-paper-display"
    },
    {
      "patentNumber": "4356429",
      "countryCode": "US",
      "title": "How Organic Diodes Make Light Using Special Molecules",
      "url": "https://patentbrief.org/patent/us/4356429/oled-organic-light-emitting-diode"
    },
    {
      "patentNumber": "3946398",
      "countryCode": "US",
      "title": "How Piezoelectric Inkjet Printing Works",
      "url": "https://patentbrief.org/patent/us/3946398/drop-on-demand-inkjet"
    }
  ]
}