Major touch panel players of TPK Holding, G-Tech, and Wintek are scaling up their production capacity for cover glass as touchscreen handheld devices enjoy rising popularity in the market, according to sources in the cover glass industry. Total cover glass capacity of Taiwan makers for the 10.1-inch panels may reach 10 million sheets per month, they said.

TPK has allocated 30% of its annual capex budget, or NT$6.5 billion (US$219 million), to the expansion of cover glass capacity.

G-Tech has invested NT$5 billion to enhance cover glass capacity, the company said. Its fourth-quarter 2011 cover glass capacity is expected to reach three million sheets per month. G-Tech said its main clients have been tablet vendors in 2011 and it will begin tapping the handset makers in 2012.

Other touch panel makers are also tapping the cover glass market. Wintek has set up cover glass production lines for 3.2-15-inch screens and reportedly will cut into Sony's supply chain. The maker currently has a capacity of 1-1.5 million sheets of cover glass per month.

Chunghwa Picture Tubes (CPT), HannStar Display, Compal Electronics and Pegatron also reportedly have investments in cover glass.

Fuji Crystal, Lens Technology, G-Tech and TPK reportedly are cover glass suppliers for Apple, with the former two supplying up to 70% of the cover glass. Fuji Crystal and Lens supply mainly to iPhones, while G-Tech supplies to iPads. TPK reportedly supplies cover glass to both Apple products.