{
  "patent_number": "US 6476836",
  "country": "US",
  "title": "How Printers Save Toner by Dropping Light-Colored Pixels",
  "original_title": "Image forming apparatus having a function of saving developing agent",
  "summary": "A Ricoh patent for printers that save toner by completely ignoring very light pixels and using a special dot pattern for darker ones.",
  "what_it_does": "This technology manages how a printer uses toner to create an image. It evaluates the darkness of each pixel against a specific threshold. If a pixel is lighter than that threshold, the printer does not print it at all, saving toner. If the pixel is darker than the threshold, the printer uses a Pulse Width Modulation (PWM) pattern, which turns the laser on and off multiple times within a single pixel space to use less toner while still representing the image.",
  "what_it_does_not_cover": [
    "Does not cover methods that reduce toner by globally lowering the laser intensity for the entire page.",
    "Does not cover color-based toner saving that adjusts ink density based on hue rather than pixel brightness.",
    "Does not cover software-based image processing that happens on a computer before the data reaches the printer."
  ],
  "filed": "2001-09-04",
  "granted": "2002-11-05",
  "expires": "2021-09-04",
  "status": "expired",
  "holder": "Ricoh Co Ltd",
  "holder_url": "https://patentbrief.org/company/ricoh-co-ltd",
  "inventors": [
    {
      "name": "Eiji Enami",
      "url": "https://patentbrief.org/inventor/eiji-enami"
    }
  ],
  "times_cited": 9,
  "tags": [
    "consumer_electronics",
    "mechanical"
  ],
  "abstract": "Image data is read in through a scanner unit, and, when a toner saving mode is set, the image data having a pixel value larger than a predetermined threshold is converted into a predetermined PWM pattern, while, for the image data having a pixel value not larger than the predetermined threshold, no output is made.",
  "url": "https://patentbrief.org/patent/us/6476836/image-forming-apparatus-having-a-function-of-saving-developing-agent",
  "markdown_url": "https://patentbrief.org/patent/us/6476836/image-forming-apparatus-having-a-function-of-saving-developing-agent/md",
  "google_patents_url": "https://patents.google.com/patent/US6476836",
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}