3M Optical Systems Division via BusinessWire: Look closely at the bottom edges of the two monitors. The one on the left has the uneven LED lighting while the one on the right has 3M’s Uniformity Tape. The Uniformity Tape eliminates the uneven LED lighting while reducing the number of LEDs for the backlight.
Uneven LED lighting can be seen in where the LEDs are located, which looks like a hotspot. When LEDs are too far apart the areas in between them are darkened. The Uniformity Tape by 3M is a clear tape with an adhesive on one side and a micro-replicated optical pattern on the other side. The Uniformity Tape is adhered to the edge of the light guide that faces the LED light source, spreading the light and increasing the the space in among LEDs by up to three times saving manufacturing costs for the LED backlight.