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Re:Questions raised about research by OpenAg Initiative at M... by DonHopkins on Monday September 23, 2019 @12:16AM (#21045877)
You're correct that the OLPC came before and spawned the whole netbook thing.

Also, the OLPC's hybrid monochrome/color display that Mary Lou Jepsen designed was truly innovative, power saving, easily manufacturable, green electronics, and it was even quite efficient and crisply legible and under direct sunlight (requiring no backlight for the high resolution 200 dpi reflective grayscale LCD pixels, which could stay on while the CPU was asleep).

https://en.wikipedia.org/wiki/Mary_Lou_Jepsen

She's written honestly about the Epstein situation, too:

https://medium.com/@maryloujepsen

John Perry Barlow typing away on his OLPC:

https://imgur.com/gallery/ogE9y

Here's an excerpt from a technical summary I wrote up in November 2008 about the OLPC display, and the problems and successes of the project:

https://donhopkins.com/home/documents/OLPC-Notes.txt

[...]

    + Display

      + Designed by Mary Lou Jepsen.
      + 1200x900, 200 dpi, 6x4 inch (152.4x101.6 mm), 6 bits (262k colors).
      + Pixel size 0.127 mm, about 1 arc minute. 
      + You can always see 200 dpi grayscale, even in direct sunlight. 
        (reflective layer)
      + You can get color from the LED backlight. 
      + Colors wash out as the sunlight gets brighter.
      + The backlight uses power (though not nearly as much as cold cathode
        fluorescent backlight).
      + You can turn the backlight down or off to conserve power. 
      + Turning off the backlight tells screen to give slightly higher 
        resolution, to make reading comfortable. 

      + Display Design Goals: 
        + Maximize the number hours of ebook reading.
        + Minimize the power consumption.
        + Maximize the resolution and readability.
        + Mesh with how human perception works.
        + Display sharp high quality text, that's easy on the eyes 
          during the day (reflective) and night (backlight).

      + Critical design innovations:
        + Remove the subtractive color filters that absorb 85% of the light.
        + Replace them with plastic diffraction gratings and lenses, 
          stamped like DVDs. 
        + Much brighter display for a given amount of backlight.
        + Can be manufactured with existing technologies and processes. 
        + Uses efficient environmentally friendly LEDs,
          instead of fragile, expensive, high voltage, cold cathode 
          fluorescent lamp backlights.

      + Combination of two separate screens: sharing an LCD glass. 
      + One normal backlit screen.
      + Another normal reflective screen. 
      + LCD is 1200x900 square grid, with 64 gray levels (6 bits).
      + Off pixels transparent, on pixels opaque. 

      + Backlit screen shines through a color filter on the 1200x900 grid. 
      + Filter gives each pixel just one color: red, green, blue. 
      + Individual grayscale pixels behave like sub-pixels of a normal 
        backlit display. 

      + Reflective screen has reflector behind LCD grid. 
      + Room light passes through grayscale LCD and bounces off of back
        reflector. 
      + 1200x900 pixels depending on ambient outside light to display. 

      + The light the user sees comes from both sources (reflected outside 
        light plus filtered backlight).
      + Color filters use fresnel prisms to pass most light, instead of 
        color filters that absorb most light, wasting less energy. 

      + The amount of color and perceived resolution depends on backlight
        brightness and outside light level. 
      + The ambient light level of the room changes the perceived 
        resolution of the display.
      + In direct sunlight you see the reflective screen (exactly 1200x900, 
        200 dpi),
      + In a dark room you see the backlit screen (approx. 800x600 
        perceived, 133 dpi), 
      + In between you see both (approx. 1024x768 perceived).
      + The "official story" is "1200x900 mono resolution, 
        693x520 color resolution". 

      + Screen layers:
        + LED backlight.
        + 1200x900 grid of color filters (fresnel prisms).
        + Semi-reflective layer.
        + 1200x900 LCD.
        + Each pixel has a single color behind it.
        + Colors are arranged in a diagonal pattern.
        + Each pixel has:
          + Fixed hue (r, g or b).
          + 6 bits (64 gray levels) of luminance.
          + Chrominance depends on relative strength of room light 
            to backlight.

      + DCON screen driver chip
        + The screen can stay on while the processor is turned off. 
        + Automatically interpolates ("swizzles") lower resolution color 
          pixels, so the unusual screen format is invisible to software. 
        + Looks just like a regular 1200x900 color framebuffer to software. 
        + DCON has different modes:
          + Monochrome.
          + Color swizzled antialiased.
          + Color swizzled not antialiased.
          + Video pass through.

      + Power saving techniques
        + Uses low power LEDs instead of high voltage cold cathode 
          fluorescent backlights. 
        + Turns off processor while leaving the screen and wireless 
          network on. 
        + Uses fresnel prisms to split most white light into primary 
          colors, instead of color filters to throw away most light. 
        + Turn down refresh rate.
        + Dynamically turn off sections of the screen.

    + Green Electronics

      + Order of magnitude less power consumption. 
      + Designed to use as many environmentally friendly components 
        as possible. 
      + Fully compliant with EU's Restriction of Hazardous Substances 
        Directive (RoHS). 
      + One of eight laptops to receive EPEAT's Gold rating for 
        environmental performance.
[...]

      + Successes
        + Two good things have happened to the project in the broader sense:

        1) Spawned this whole netbook thing. 
           + Nobody was doing that before.
           + Now 15 different major companies are doing the same thing. 
           + Finally people are exploring the low cost low power end 
             of the laptop spectrum. 
           + OLPC is still unique in that it was ruggedly designed to be
             dropped and survive. 
           + Other companies have not figured that out yet, and are still
             making cheap low quality laptops.

        2) The free software community is widely in favor of the project. 
           The deal with Microsoft got bad press, and most people in the
           free software community mistakenly think the free software part
           is over, and OLPC is now shipping laptops with Windows. 
           But actually they are not.

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