Privacy filter

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A privacy filter is a flat plastic disc . It is a notebook - screen set and restricts the viewing angle to about 30 °. The filter film is to prevent unauthorized persons can look from the side of the screen.

  • Microscope photograph of a lamellar privacy screen

  • Principle drawing of how a lamella protective film works

The eye filter consists of vertical slats, which are supported on the top and bottom by a transparent protective film. In the micrograph on the right, the distance between the lamellae is approx. 60 µm. They reduce the transmission brightness by approx. 30%. With a film thickness of approx. 600 µm, 200 µm are allotted to the web height and 200 µm to each of the carrier films. This results in a geometric shadowing at a side viewing angle of approx. 25 °. The view from above is not restricted. Such films exist since at least 2004 z. B. from 3M .

Electrically switchable privacy screen

These can be switched on electrically. In 2004, Toshiba introduced a display in which a black and white display sits in front of the actual LCD , which can not only be switched on and off, but also display a logo or something similar that can only be seen from the side. In 2008 LG developed the so-called Viewing-angle Image Control Display . In 2016, HP announced two notebooks with built-in privacy filters.

See also

Intelligent glass - an electrically tintable pane, also known as electrochromic, which can be darkened in several stages in order to restrict visibility or reduce solar radiation.

Individual evidence

  1. ↑ Jörg Wirtgen: Notebook display against other readers. In: heise online . March 24, 2004, accessed August 25, 2016 .
  2. ↑ LG Display Launches Privacy Protection LCD Panels for Notebook PCs. October 13, 2008, accessed August 25, 2016 .
  3. ↑ Kamil Artur Nowak: New HP notebooks: privacy filters at the push of a button. In: heise online . August 25, 2016. Retrieved August 25, 2016 .
  4. ↑ HP Introduces World's Only Notebooks with Integrated Privacy Screens. HP Inc. , August 25, 2016, accessed August 25, 2016 .