大东南：公司光学膜主要生产扩散膜基膜，主要应用于液晶显示背光模组中

Group 1 - The company primarily produces diffusion film base membranes, which are mainly used in liquid crystal display backlight modules [2] - The optical film enhances display effects by improving light distribution [2] - The information was provided in response to an investor inquiry on an interactive platform [2]