The New iPad Display Has Been a Challenge to Manufacture

The new iPad display has been a challenge to manufacture, according to the NPD Group's DisplaySearch.

Apple is reportedly tapping Sharp, Samsung, and LG to make displays.

The situation at Sharp has been a major source of speculation ever since the company announced a new strategy for producing oxide TFT displays last April. Our understanding is that Sharp has been producing samples of the iPad 3 display using IGZO TFTs, but it is not clear whether the quality or manufacturing yields are acceptable to Apple and Sharp. There has been speculation that Sharp has switched back to a-Si TFT production while they work on the IGZO process; meanwhile, our research indicates that Samsung and LG Display are producing the new panels using a-Si TFT. It has been a challenge using this technology, as 264 ppi is believed to be the upper limit of pixel density for a-Si TFT.


Corroborating previous reports DisplaySearch indicates that the tablet likely uses a dual-LED light bar design.

Regardless of the TFT technology, the doubling of the pixel density means a significantly smaller aperture ratio, which means that a brighter backlight is needed. Our research indicates that the iPad 3 panel has at least twice as many LEDs than the iPad 2, which had 36. Even allowing for increases in LED efficiency, this most likely means a significant increase in power consumption for the panel. The slightly larger and heavier case as compared to the iPad 2 suggests Apple is using a larger battery in order to accommodate the high resolution display with more LEDs than the previous generation, without decreasing battery life.

Apple notes that when squeezing four times the pixels into the same space, signals can get crossed, colors become distorted and images get fuzzy. To get around this problem they used SHA (Super High Aperture) pixel designs. By applying a 3 µm thick photo-definable acrylic resin layer to planarize the device and increase the vertical gap between the ITO pixel electrodes and signal lines Apple was able to increase the aperture ratio and reduce unwanted capacitive coupling.

Read More [via AppleInsider]