After HTC kicked off the trend with its “Butterfly,” there is a great deal of momentum around the adoption of Full HD (FHD; 1920×1080) displays in smartphones. Like the Butterfly, many of these devices will use 5” FHD displays, with a stunning 441 ppi (pixels per inch) resolution.
Other brands jumping into the FHD smartphone display game include Samsung, Sony, LG, Motorola, Huawei, ZTE, and Oppo; many of these devices will be launched at CES or MWC. Most of these displays are LTPS LCDs, which enable high performance at relatively low power consumption, in sizes ranging from 4.7” to 5.5,” with 400 to 470 ppi; Huawei’s Ascend Mate will use a massive 6.1” display.
LTPS is the leading technology for such high resolution displays, at least until IGZO is mature. With the demand for FHD smartphone displays expected to take off, the supply of key components in 2013 will be a critical element for production:
- TFT: Although most LTPS panel makers can produce 400+ ppi displays, the requirements for FHD smartphone displays is much critical than for other devices. Only tier-one LTPS panel makers can supply displays at the performance and low power consumption required be top brands. As always, Samsung is in a unique position as it also uses LTPS as a backplane, but for AMOLED.
- Color Filter: For high resolution smartphone display, panel makers prefer to purchase color filters from merchant suppliers, because the black matrix must be very narrow in such a high resolution panel to enable high transmittance rate and low power consumption. However, merchant color filter suppliers have not increased capacity over the past few years, and some existing capacity has been converted to touch sensor manufacturing.
- Driver IC: Smartphone brands and panel makers use the MIPI interface, which has speed close to 1 Gbps per channel and needs at least 4 channels for a high resolution display. Only tier-one IC makers can supply such devices, which require a narrow die size, meaing the ICs need to be manufacture in 80 or 55 nm process, typically on 12” IC foundry lines. However, in addition to the high cost of developing and manufacturing such devices, 12” capacity for driver IC is only available from a few makers. In addition to foundry capacity, both the ACF (anisotropic conductive film) and the IC packaging need to be adjusted for FHD smartphone display driver IC, and the supply of each may be limited compared to those for HD (1280×720) or WVGA (800×480) driver IC. These issues could limit the supply of FHD driver ICs in 2013.