Due to their clear color are used by silver Smith and glasses industry, etc.

由于钎焊后表面颜色浅，可适用于银饰、眼镜等行业的加工。

youdao

Due to the use of Film Patterned Retarder (FPR) technology, LG's 3D glasses are battery-free, lightweight and inexpensive, making them ideal for watching 3D content in large groups and comfortably for longer periods of time.

ENGADGET: LG unveils new 3D glasses, hopes lighter and better looking spectacles drive adoption