Purple Screen

How to use a purple screen

This page fills the display with #800080, the web color named "purple": red and blue subpixels at level 128 out of 255, and green off. Because green is fully off, anything green on this screen is a fault. And because the field is fairly dark, brighter patches from the backlight are easier to see than on a bright color.

1. 1

   Dim the room a little. Reflections from room light make a darker field look uneven.

2. 2

   Open it full screen. Browser toolbars around the field hide the edges and corners.

3. 3

   Turn off color filters. Night mode and blue-light filters reduce blue, which shifts purple toward red.

4. 4

   Scan slowly. Work across the screen one section at a time, then look closer at anything that stands out.

What a purple screen can reveal

A bright green dot is a pixel with its green subpixel stuck on. Green stands out strongly against purple.

A red or blue dot, or a dark one, is a pixel where one or both of the lit subpixels does not work.

Brighter or cloudy patches, often near the edges, can point to uneven backlighting. Some unevenness is normal on many displays, so check the manufacturer's warranty terms before deciding a panel is faulty.

Purple has green switched off, so it cannot show whether the green channel works. If the White Screen looks pink or magenta across the whole display, check green directly with the Green Screen. For a brighter red-and-blue mix, use the Magenta Screen, and confirm any dot that stays put with the Dead Pixel Test.

This screen's exact value has its own #800080 color page, with its RGB and HSL values and its contrast against black and white.