LCD Polarity Issues

 

Fotolia.com">LCD screens can be problematic.Liquid crystal display (LCD) technology has helped shape the face of our modern laptops and television screens but if you've ever had to adjust the screen to better see the picture or experienced strange image problems, you've experienced issues with your screen's polarity. Polarity electrically controls the filtering of light at the pixel level by containing light vibrations in the same plane. However, depending on the position of your screen or the light requirements of what you are viewing, you may experience some common issues.FlickerWhen an LCD screen does not have the proper voltage transmitting light, the pixels in your screen tend to flicker. However, modern LCD screens have alternating pixels in anti-phase which makes the flicker over areas usually unnoticeable.Dot CrawlIf your LCD screen flickers substantially, it may mean that your common-electrode voltage is not set up correctly and you may perceive a dot crawl effect on plain and medium bright colors, where the pixels slowly appear to move in dots along the frame.Voltage SettingGrossly incorrect voltage settings could result in image sticking, essentially "burning" the image into your screen so that it will be visible even after the image is replaced.Colors on ScreenThe colors you can see on your LCD screen vary depending on the angle at which you are viewing the images. Usually, the image will look light if looked down on and look darker if looked up at. Newer liquid crystal modes do not experience this problem as much but may have longer response times or lower contrast.Motion BlurMotion blur is the result of the sample-and-hold effect when an image is held on screen and the eye tracks it from one frame to the next. This makes it difficult to see motion properly and is a problem in some LCD screens. The pixels may have a slow response time, assisting in the cause of this effect, but as the frame rate increases and development moves toward flickering the screen's backlight, this effect should be reduced. References Techmind: Active Matrix LCD Technology