TDG's main business is R&D, manufacturing, sales of sapphire crystal materials.

TDG Holding Co., Ltd was founded in 1984 and listed on the Shangahi Stock Exchange in 2001. It is the first listed company in china directly controlled by a natural person. After forty years of development, TDG has multiple holding and participating companies, and has now formed four major business segments: electronic materials, electronic modules, green energy and intelligent equipment. Its business covers the upstream and downstream of the electronic information materials industry chain. TDG's products include sapphire boules, sapphire ingots, sapphire substrates and optical window cover, and can be customized to meet customer needs. The products are widely used in LED lighting, consumer electronics, smart wearable, industrial optics and medical beauty.