Dismiss
There will be a system update on Friday, May 5th, 6 PM ET. You may experience a brief service interruption.
Browse Prior Art Database

Interactive compensation for differential ageing in P(O)LED display

IP.com Disclosure Number: IPCOM000007427D
Publication Date: 2002-Mar-25
Document File: 1 page(s) / 52K

Publishing Venue

The IP.com Prior Art Database

Abstract

ID608424

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 100% of the total text.

ID608424

Interactive compensation for differential ageing in P(O)LED displays

To avoid coloration in P(O)LED displays

P(O)LED devices degrade during operation, resulting in a change (usually a reduction)

in light output at a given current density. In colour displays this degradation process results in

coloration ("white" is no longer white, but has for example a green shade), if the degradation

of the individual colour components have different degradation rates. This effect is

unacceptable and must be minimised in production displays.

Here, we propose a more simple method for compensation of the coloration. The

relative brightness of the individual colours can be set by the user by means of an external

function that is capable of changing the current for the three colours. Visual inspection by the

user is applied as a monitor for the quality of the colour of the display.

The external function can not only be used to compensate for differential ageing, but it

can also be used to set the colour of the display to the individual wishes of the user.

In order to avoid over-stressing, resulting in a short operational lifetime of the device,

the external function can only adjust the relative current of the pixels. The total current for the

three colours is kept constant.

Disclosed anonymously.