Gelonghui, May 22丨Changyang Technology (688299.SH) recently said during a survey receiving institutional investors that optical substrates mainly use polyester slices as raw materials. Because they require excellent optical properties such as low haze, high light transmittance, high surface finish, and small thickness tolerances, they all have high requirements for polyester slices, processing equipment, and workshop cleanliness, etc., so optical base films are one of the fields with the highest technical barriers in the field of optical films. By continuously improving the key indicators of optical substrates such as light transmittance, haze, appearance, and adhesion, the company has increased the share of shipments of products such as optical pre-coating films for displays. The application field has also been continuously expanded, and products such as OCA release film substrates have been shipped in stable batches.