Optical bonding is the process of pasting a transparent protective plate or touch panel on the front of the display device with a transparent resin to improve the visibility of the display. By matching the refractive index of this transparent resin with it of the transparent protective plate or touch panel substrate, the light reflection at the bonded surface is significantly reduced. Since the reflection can be significantly reduced, the reflection of bright light such as sunshine in outdoors can be reduced, and the light from the display device cannot be returned to the inside due to the reflection, which improves the luminance, and the visibility is improved by both improvements. In addition, the optical adhesive between the display device and the front transparent plate eliminates condensation in this gap, and makes it more resistant to pressure from the outside of the front plate. Not only to improve the visibility, but also to realize highly reliable even in harsh environments.
The resin is a transparent optical adhesive sheet (OCA: Optical Clear Adhesive) or a transparent optical resin (OCR: Optical Clear Resin).