Air bonding and optical bonding are the main bonding technologies used to attach touch panels to LCDs. More and more touch displays are choosing optical bonding because it has better display and touch performance. We can also provide bonding.

Producing a touch display is the process of attaching the touch panel (TP) to the liquid crystal module (LCM).

From the perspective of bonding methods and materials, there are two main bonding technologies, namely air bonding and optical bonding.

air bonding

Air bonding uses tape (usually double-sided tape ) to bond the touch screen to the LCM along both sides of the outer frame. Therefore, it is an internal air gap. That's why people also call bonding, frame bonding.

advantage

• Mature technology and stable output
• Simple process and low cost
• Simple rework process

shortcoming

• The air gap between TP and LCM increases light reflection and reduces light transmittance, thereby reducing display performance.
• The air gap provides room for dirt and dust particles to enter.
• The structure is thicker

Optical bonding

Optical bonding is a bonding technology that fully applies optical glue between the touch panel and the LCM to eliminate the air gap and make the screen thinner. 

Optically clear adhesive (OCA) and optically clear resin (OCR) are typical optical adhesives. They are transparent, allowing light transmission over 90%.

Advantages of removing air layer:

• Low light reflection, high transmittance, maintain display quality
• Reduce light loss, achieve the same brightness and save power
• Good touch performance
• No space for dust and dust particles after assembly

shortcoming

• The process is relatively complex, the yield is low, and the cost is increased.
• Once there is dirt or air bubbles inside, the entire screen needs to be replaced.

How to choose between air bonding and optical bonding?

Comparison between air bonding and optical bonding

Review the pros and cons of the above two bonding technologies:

Tips for making a choice

To choose the suitable fitting method for your touch screen, we can share our project experience for your reference:

• From the perspective of display and touch performance, optical bonding is better than air bonding regardless of cost. 
• However, given its proven technology, air bonding is a viable option.
• In our project experience, most projects use capacitive touch screens to choose optical bonding, and among projects using resistive touch screens, some projects have specific requirements for applying optical bonding. 

Currently, both technologies are generic and the choice depends on the specific requirements and budget of the project.

We can provide two lamination technologies for touch screens according to your requirements. Welcome to call us for more information.