Cover Glass

Glass Cutting

Glass is selected by specification. Common glass requirements will be silicate types of glass. There are multiple chemistries of glass including economical solutions such as Sold-Lime Silicate and more premium chemistries such as aluminosilicate glass which has a >99.5% purity. Our factory can work with multiple times of glass brands and chemistries.

Raw glass substrate will arrive in large sheets. The first task for lenses and screen protectors is to section the glass for optimal processing size. This involves scribing and cutting using automated cutting equipment.

CNC Shaping

Modern electronics does not just require straight glass cuts, but glasswork with edge geometry and even cut holes for tactile buttons to operate. This requires the shaping of a Waterjet Computer Numerical Control ("CNC") Cutting System. This is a subtractive manufacturing process to remove and size down the glass and edge geometry. Our factory can perform 2D, 2.5D, and 3D edge geometry which requires compound angle cutting. This system is fully computerized and automated for high level precision cutting for modern microelectronic devices.


After shaping and processing, the glass surface needs to be polished. This is performed in a rotary polishing system with fixtures for the specific lenses. A specific abrasive compound is added with the polishing pads to create optimal clarity and uniformity.

Ion Exchange

Chemical strengthening of glass is a process of ion exchange. After all cutting of the glass is performed, the glass is placed into a molten potassium salt solution. The charged partials of Potassium ions ("K+") will replace smaller Sodium ions ("Na+") on the surface of the glass. The process is strictly controlled for a specific Depth of Layer ("DOL") exchange relative tot he zero stress point internally on the glass. As the glass cools from the ion exchange the larger potassium ions create a compressive stress layer forming a tough exterior on all exposed edges. This is the primary reason that our factory performs these processes internally for ion exchange versus cutting glass externally processed. The depth of layer is controlled to ensure that the inner layers and exterior layers have different levels of flexibility so the resulting glass is ruggedized to be flexible without shattering.

Plasma Cleaning

Before applying any surface treatments, it is important to clean the glass. After traditional cleaning methods, a plasma cleaning is utilized. Plasma cleaning utilizes ultra-violet ("UV") light generated in the plasma to decompose most organize surface contaminations. This is essential for removal of oils or greases that can be inherent from previous handling or processes.

3D Hot Bending

Modern electronics also is no longer isolated to flat surfaces. Many mobile devices may now have curved edges. There are also requirements for concave and convex glass geometry. Making lenses and screen protectors to serve this market requires 3D Hot Bending processes. This process utilizes a series of various shaped holding surfaces to gently apply to heated glass to shape it towards a desired shape. The glass must be repeatedly locally heated and cooled in stages to perform the necessary bend geometry.

Film Lamination

Glass lenses and screen protectors often require laminated thin film application. These may include film-applied surface treatments like anti-reflective ("AR"), privacy films, optical bonding, and AB glues.

Customer applied screen protector kits utilize AB glues for user applied non-permanent applications like used on many cellular phone screen protectors. AB glue is a compound of two types A & B respectively. Screen protector AB glues can be materials such as acrylic glue on one side and silica gels on the other side. Silicone adhesives are popular because they provide a reasonably strong bond that is non-permanent to apply and remove if desired without deterioration of the surface or leaving a residue.


Cover glass and screen protectors are not required to simply be clear glass, but may often seek to have screen printing. This can be used to mask inactive and unused areas, to place branding, buttons/icons for touch functions, and detailed artwork printing on glass. Printing methods can use silkscreen for larger fonts and areas, or other types of glass printing for high precision artwork. In addition to additive printing, subtractive etching is also possible for a watermark appearance.

These features are in addition to glass treatments such as Anti-Glare ("AG"), Anti-Reflective ("AR"), Anti-Fingerprint ("AF") oleophbic coatings, privacy films for secure devices, and other treatments. OSD can work with your requirements to support many combinations to meet your requirements.

Quality & Packaging

Screen Protectors and cover glass lenses equally need to be validated and quality controlled. Our factory has an extensive range of test equipment to validate surfacing, ion exchange strength, optical properties, and other services performed. We can maintain the quality and consistency and meet the more strict expectations of glass makers available to process the most prestigious name brands in glass supply and their proprietary strengthening in our facilities.

Cover glass is often applied to displays or touchscreens, while our screen protectors are customer applied. We are able to support integration, bulk packaging for wholesale service centers, and individual beauty box packaging for retail readiness. Our factory also has safety data sheet ("SDS") for screen protector cleaning, wipe, and application kits to be included in retail solutions. We can customize packaging and contents to meet all requirements of our customers.