AU Optronics (AUO) has received orders from five major China handset vendors for Ultra HD (4K) handset panels and expects to mass produce the technology by the end of 2015, according to industry sources.

The sources did not specify customers but mentioned that Xiaomi, Huawei Device, Coolpad, ZTE and Lenovo currently make up 50% of AUO's handset panel revenues.

AUO plans to mass produce the technology within the second half of 2015 when it is also expected to mass produce Full HD in-cell displays, the sources said.

The sources also added Samsung Display is also considering 4K OLED handset display production in the second half as well.

Additionally, Sharp is likely to produce 4K IGZO handset panels in 2015, the sources noted.