Investigation on Possible Materials of Display Cover Glasses

Materials Used for Mac Displays

Mac displays come in two categories: naked LCD screens and glass LCD screens.

Naked LCD screens are used on many of the older portable Macs and most third-party desktop monitors.

Glass LCD screens, like the ones used in recent iMacs, are naked LCDs with a glass panel in front of them. [3]

=> In Mac displays, they use "glass" for cover materials.

Typical Materials for Display Cover Glass

Three main types of cover glass typically found on displays are soda-lime, Dragontrail Glass™, and Gorilla Glass™. [1]

f:id:horifumi7:20201205175948p:plain

Figure 1. Comparison of Commonly Used Cover Glass Materials (image from [1])

=> In most cases, glass materials are used for display cover glasses. (When it comes to "extra" screen protectors like the sheets that you put on your electronic devices, plastic materials, such as TPU and PET, are also commonly used. [5])

The Reason Why We Need Screen Cover Materials

Why would someone need to add a cover glass to the front of their LCD? Most LCDs have plastic surfaces that are not vandal or weatherproof. This component is called a cover lens. The material does not hold up well against scratches or damages, leaving your LCD with large vulnerabilities. To protect your LCD display, you will need to install a cover glass or other strengthened polycarbonate material to the LCD for protection. [2]

=> Although "glass" is the main material for material layer that comes directly on top of the LCD display, we can see that polycarbones are also sometimes used.

An Example of a Polycarbonate Cover Glass

Polycarbonate means durability and safety of your electronic display due to its high shock- and impact resistance and good flammability properties. PSC has a wide range of clear and custom coloured polycarbonate readily available for processing into application specific solutions.

Typically, a surface treatment is applied, such as Fine Mat, Hard Mat or HC clear, to provide the polycarbonate cover glass solution with the necessary and application specific surface features. This may be features such as anti glare or scratch resistance from a hard coating for polycarbonate. The polycarbonate sheet can be processed into customized size and shape. [4]

=> Polycarbonate is also an possible choice for display cover glass material.

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Figure 2. Key Features of Polycarbonate Coverglass (image from [4])

Example of Possible Material

Material Datasheet

Polycarbonate: Impact Resistant Display Windows; PSE

https://psc.dk/wp-content/uploads/2020/03/Polycarbonate.pdf

https://psc.dk/en/products/polycarbonate/polycarbonate/?utm_referrer=https%3A%2F%2Fwww.google.com%2F

Surface Treatment

HC Clear is a clear hard coating that can be applied to coloured and clear acrylic, and clear and coloured Polycarbonate. HC Clear provides high scratch and abrasion resistance, graffiti resistance, improve all weather performance and has a great optical quality. HC Clear can be applied on both sides of the optical filter regardless of the base material.

https://psc.dk/en/resources/other-surface-treatments-for-polymer/hc-clear/

=> Polycarbonate cover glass supplied by PSE is a possible material. This material is also adequate for use in the medical medical field, where the requirements include: Chemical & cleaning resistance, Maximum readability, EMI shielding, Scratch resistance, and Fire behaviour rating. [6]

https://psc.dk/en/applications/industrial-applications/medical/