- on Miscellaneous Electronics
- Published in issue 10/2001 on page 0
how to identify and (sometimes) correct them
TFT monitors and digital cameras are becoming steadily more popular and more affordable. Unfortunately, users of such devices are frequently confronted with pixels that do not function correctly. How can you identify such pixels, and what can you do to correct them?Dead pixels, stuck pixels, hot pixels: all of these terms refer to pixels in displays or CCDs that don’t work properly. Users of TFT screens and Digicams complain increasingly about this problem. However, this is certainly not the result of poor product quality or inadequate quality control by the manufacturer. We are simply being confronted with a consequence of the fact that we demand increasingly higher resolution from our screen or camera. In the case of a 15-inch TFT monitor with a resolution of 1024 × 768 pixels, there are no less than 2,359,296 transistors on the glass plate, with their associated colour filters (red, green and blue). If something is wrong with one of these transistors, its associated switching electrode or a lead, there is a chance that this pixel will always remain fully dark or fully light.