Optical Bonding Service

Originally developed for avionics and military displays, optical bonding is now moving into industrial and consumer applications such as touch screens, TVs, smartphones, digital signage and medical imaging.

Optical bonding (LCD bonding, direct bonding) refers to a protective glass or touchscreen that is glued in front of a display to enhance its readability in high humidity outdoor environments. When a normal display is used in an outdoor environment, there are some factors that affect its readability. The most common one is "fog", or condensation, which forms on the inner surface of display's vandal shield. Another factor is the reflection of sunlight, which causes a mirror-image on the display. Both phenomena can be solved by using optical bonding.

Optical bonding is the use of an optical-grade silicon-based adhesive to glue a glass or touchscreen to the top surface of a display. The assembly is cured in a process that affixes the display together while solidifying the adhesive. The main goal of optical bonding is to improve the display performance under outdoor environments. This method eliminates the air gap between the cover glass and the display. Moreover, anti-reflective coating is often used in optical bonding glass. The real problem for display readability in outdoor environments is not the display's brightness but its contrast. Contrast means the ratio of the white level to the black level; in other words, the contrast ratio of display means the difference of light intensity between the brightest white pixel and the darkest black pixel. The main purpose of optical bonding is to increase the display's contrast ratio by reducing the amount of reflected ambient light.