Optical Bonding

BSI > Capabilities > Optical Bonding

OUR CAPABILITIES

Glass Bonding / OCA Bonding / OCR Bonding

Bi-Search International has been providing optical bonding services since 2013. Over many years of experience in optical bonding, we have established a base of materials and processes that can be tailored to your specific application. Whether your application is indoors or outdoors, we have a solution for you. Our products have been pushed to the limits and are tried and true on the field.

What is Optical Bonding?

Optical bonding is a process where a layer of resin (OCR) or film (OCA) adhesive is applied between the glass or touchscreen and TFT LCD panel of a monitor, bonding them to make a solid laminate with no gaps or pockets of air. When choosing a screen for any project, it’s important to evaluate the environment and operating conditions the screen will need to endure. Industrial grade screens and panel PCs are made rugged with all types of features available to withstand any type of application. One such feature available to consider is optical bonding.

Optical bonding is popular among the medical, military, transportation and retail sectors whereby a higher performing display is required due to the harsh environments. Optical bonding is suited to industries that tend to use rugged displays in high reliability environments or industries where displays need to be seen in high ambient light conditions. The process of optical bonding is particularly well-suited and much more effective when applied to devices that operate outdoors or in heavily lighted environments.

In-house automated Optical Bonding process with high accuracy and consistency

Capability to Glass Bonding

Capability to bond various sizes between 2.8” and 105” OCA Bonding and OCR Bonding

Class 1,000 / Class 10,000 Clean Room

Multiple OCR / OCA adhesive configurations depending upon performance / environmental requirement

Adjustable Optical Bonding line thickness

In-House equipment and testing

Enhance Clarity with Optical Bonding

Optical bonding significantly improves clarity and visibility by eliminating the air gap between layers, which causes light refraction. Each medium has its own refractive index, and as light passes through different mediums, it bends according to each medium’s refractive index. This bending results in scattering, leading to reduced clarity. Optical bonding solves this issue by creating a single refractive index, making it an essential technology for maintaining clarity.

The refractive index of the air gap is approximately 1.0, while both the glass and the LCD panel have similar refractive indices around 1.5. By removing the air gap between the glass and the TFT LCD panel, optical bonding aligns the refractive indices of both components, effectively reducing distortion.

To achieve optical clarity, it’s crucial to match the refractive indices of all the mediums involved. Optical bonding accomplishes this by applying a resin or film adhesive between the glass and the LCD panel, allowing light to pass through without distortion.

OCA Bonding Machine

OCA Bonding

(Dry Bonding with Clear Adhesive Sheet)

OCA Bonding, or Optical Clear Adhesive Bonding, is an alternative form of bonding which is well-suited for higher production volumes. OCA Bonding uses an optically clear adhesive film to bond a touchscreen or cover glass to the surface of the display. The adhesive film layer is thin but effectively protects the screen from environmental factors. Although there are some mechanical limitations to OCA Bonding, we offer multiple thickness of film which helps to overcome those challenges.

OCA Bonding Available Size: 2.0” - 65”

In-House Automated / Semi-Automated

Optical Bonding Clean Room A

Class 1,000
2,500 Sq. Ft.

Optical Bonding Clean Room B

Class 1,000
2,500 Sq. Ft.

OCA bonding and OCR bonding require a clean room environment to prevent debris and trapped air during the bonding process. Bi-Search International operates two large-scale optical bonding clean rooms to effectively eliminate any potential complications.

OCR Bonding

(Wet Bonding with Clear Resin)

OCR Bonding, also known as Optically Clear Resin Bonding, is a technique used to bond two or more surfaces together. OCR Bonding involves applying a thin layer of clear silicone-based resin between a display and cover glass or touchscreen. The adhesive layer spreads evenly, without any bubbles or debris, through OCR Bonding. This process can be done both manually and with automated equipment. OCR Bonding is preferred in applications where substrates are irregularly shaped or curved. Additionally, OCR Bonding can provide excellent optical clarity and minimize the appearance of visible gaps.

OCR Bonding Available Size: 2.0” - 105”

In-House Automated / Semi-Automated

OCR Bonding Machine

Benefits of
Optical Bonding

Optical bonding reduces the number of air gaps between the glass and LCD module, which reduces reflections and glare. By bonding the glass and LCD module together, optical bonding improves contrast, color accuracy, and overall visibility, particularly in bright outdoor environments. The reduction of internal reflections through optical bonding makes it easier to view the display under various lighting conditions.

Adding additional resin in optical bonding enhances the structural integrity of the display assembly. The resin layer acts as a hardened adhesive that absorbs shock. Optical bonding increases the display’s resistance to physical impacts, scratches, and other potential sources of damage. This is particularly important for rugged devices, outdoor displays, and touchscreens used in demanding environments.

In an environment with wide temperature ranges and fluctuating humidity, it is easy for condensation to cause screens to become foggy from moisture. The optical bonding process fills the air gaps between the glass and LCD modules, helping to prevent the potential of condensation, as well as the accumulation of moisture, dust, and other particles. Optical bonding can extend the lifespan of the display and maintain its performance over time.

Optical bonding is crucial for touchscreens, as it enhances touch sensitivity and improves the overall user experience. The air gaps between the glass and LCD module cause parallax which is a difference in the apparent position of an object viewed along two different lines of sight. Optical bonding removes the air gaps and reduces parallax error, resulting in a smoother and more natural touch experience.

Optical Bonding

OUR CAPABILITIES

Glass Bonding / OCA Bonding / OCR Bonding

What is Optical Bonding?

Enhance Clarity with Optical Bonding

OCA Bonding

Optical Bonding Clean Room A

Optical Bonding Clean Room B

OCR Bonding

Benefits of Optical Bonding

01. Improve Optical Performance

02. Enhance Durability

03. Moisture and Dust Resistance

04. Better Touch Experience

OUR PROCESS OF OPTICAL BONDING

LCD Panel (OLED/E-Ink) to Glass Bonding

Incoming Inspection

Cleaning LCD Panel and Cover Glass or Touch Panel

Optical Bonding (LCD Panel to Glass Bonding)

Curing Bonding Material

Outgoing Inspection

Packaging

OUR PROCESS OF OPTICAL BONDING

LCD Module to Glass Bonding

Incoming Inspection

Disassemble LCD Module & Remove LCD Panel

Cleaning LCD Panel and Cover Glass or Touch Panel

Optical Bonding (LCD Panel to Glass Bonding)

Curing Bonding Material

Reassemble Bonded Panel to Module

Outgoing Inspection

Packaging

Incoming Inspection

Disassemble LCD Module & Remove LCD Panel

Cleaning LCD Panel and Cover Glass or Touch Panel

Optical Bonding (LCD Panel to Glass Bonding)

Curing Bonding Material

Reassemble Bonded Panel to Module

Outgoing Inspection

Packaging

Our Industries

Our Products

Benefits of
Optical Bonding