What a indigo screen is used for
- Low-brightness ambient light that does not disturb a dark room
- Deep, moody backgrounds for photography
- A dark alternative to black that still shows the screen is on
Indigo screen online: #4B0082 at full screen
Indigo is the colour Newton inserted between blue and violet when he wanted seven colours in the spectrum to match the seven notes of a musical scale. Most people cannot reliably distinguish it from blue or violet in a rainbow, and colour scientists have argued ever since about whether it deserves its place.
On a display it is unambiguous enough: #4B0082 is red and blue with red held low and green at zero, producing a dark, saturated blue-violet. Because it is dark, it works as ambient light in a room where a brighter colour would be intrusive.
With green fully off, indigo shares the diagnostic property of purple — any green in this field is the panel adding it.
How to get a full screen indigo background
Press the fullscreen button on the player above, or the F key. Escape returns you to the page. On a desktop browser F11 does the same job and hides the browser's own toolbars as well.
The colour box is a control, not a picture: use the hex field to enter any value, pick another shade from the palette, or download the current colour as a PNG at your screen's resolution. Whatever you set is written into the address bar, so the link you copy reproduces exactly what you are looking at.