Chemically strengthened glass is a type of glass that has increased strength as a result of a post-production chemical process. When broken, it still shatters in long pointed splinters similar to float glass. For this reason, it is not considered a safety glass and must be laminated if a safety glass is required. However, chemically strengthened glass is typically six to eight times the strength of float glass.
The glass is chemically strengthened by a surface finishing process. Glass is submersed in a bath containing a potassium salt (typically potassium nitrate) at 300°C (572°F). This causes sodium ions in the glass surface to be replaced by potassium ions from the bath solution.
These potassium ions are larger than the sodium ions and therefore wedge into the gaps left by the smaller sodium ions when they migrate to the potassium nitrate solution. This replacement of ions causes the surface of the glass to be in a state of compression and the core in compensating tension. The surface compression of chemically strengthened glass may reach up to 690 MPa.
There also exists a more advanced two-stage process for making chemically strengthened glass, in which the glass article is first immersed in a sodium nitrate bath at 450°C (842°F), which enriches the surface with sodium ions. This leaves more sodium ions on the glass for the immersion in potassium nitrate to replace with potassium ions. In this way, the use of a sodium nitrate bath increases the potential for surface compression in the finished article.
Chemical strengthening results in a strengthening similar to toughened glass. However, the process does not use extreme variations of temperature and therefore chemically strengthened glass has little or no bow or warp, optical distortion or strain pattern. This differs from toughened glass, in which slender pieces can be significantly bowed.
Also unlike toughened glass, chemically strengthened glass may be cut after strengthening, but loses its added strength within the region of approximately 20 mm of the cut. Similarly, when the surface of chemically strengthened glass is deeply scratched, this area loses its additional strength.
Chemically strengthened glass was used for the aircraft canopy of some fighter aircraft.
- 6-8x stronger than regular glass
- Opaque with 0% transparency
- 96% reflective
- Comes with protective laminate over coating
- Manufactured in the USA
- Quantity discounts available
- Same day shipping
- International shipping
- Military training simulators, periscopes
- Broadcasting, photography, projection.
- Optics, astronomy, physics, lasers
- Barcode scanners
- Hollywood special effects
- Explosive testing, high speed photography
- Kleidoscopes, product photography
- Ophthalmology eye tests, dental mirrors
We cut and ship the glass first surface mirrors immediately. We ship mirrors under 24″ x 30″ in carefully packaged boxes with FedEx while larger mirrors are more extensively packaged in a custom wood crate and shipped via freight. All shipments are fully insured to protect our customers. Less than 2% of our shipments arrive broken. On the rare occasion breakage should occur, we will gladly replace the mirrors–just send us pictures of the mirror and damaged box.
First surface mirrors allow barcode scanners to read multiple angles of the product without losing quality or creating a double image.
1λ first surface mirrors work flawlessly when used as a binocular mirror up to 15x. For greater magnification, we offer λ/4 flatness.
A first surface mirror reflects lasers in different ways to create stunning effects or for research and development of new products.
Frequently Asked Questions
Sizes up to 32″x50″ are cut from our 1λ stock. Sizes larger than this, up to 72″x96″, are cut from our 4-6λ stock sheets.
Yes, but only if the size is larger than 32″x50″. That’s our maximum size for the high grade 1λ flatness mirrors in 1/4″ thickness.
The best quality is our 1/4″ thickness, which is 1λ per inch.
1/8″ thickness: 8λ per inch
Yes, glad to quote and coat curved glass. The coating we use is silver for curved mirrors instead of aluminum. Please contact us with the details of what you’re looking for, and the quantity, and we’re glad to quote it.
Please feel free to order samples first to evaluate the quality of our mirrors. Limit 1 per customer.
Glass First Surface Mirror Sample – 1/4″ thickness (Random Size)
$2.95 Add to cart
Glass First Surface Mirror Sample – 1/8″ thickness (Random Size)
$2.95 Add to cart
Glass First Surface Mirror Sample – 1mm thickness (Random Size)
$2.95 Add to cart
Glass First Surface Mirror Sample – 1.9mm thickness (Random Size)
$2.95 Add to cart
Less than 2% of our shipments arrive broken. If it should arrive broken, please send us pictures of the mirror and box right away, and we will send replacements.
Small mirrors are carefully packaged in bubble wrap and shipped via fedex. Larger mirrors are crated with several inches of styrofoam on all sides. In the rare case that your mirror arrives broken, just send us pictures of the broken glass and box and we’ll send replacements right away.
We use a high quality wet sander to take the sharp edges off before shipping.
Our size tolerance is typically +/- 1/16″. Please contact us for a custom quote if you need a higher level of accuracy.
We are standing by to begin cutting and packaging your order immediately.
The standard score-and-break method is recommended. You’ll need to purchase a quality glass scoring wheel and glass pliers. Sandpaper or a sanding block is useful for sanding the sharp edges.
We recommend Gunther Mirror Mastic and VHB tape for the backside of the glass.
1/4″ thickness – 3.3 lb / sq ft
1/8″ thickness – 1.6 lb / sq ft
1.9mm thickness – 1 lb / sq ft
1mm – 0.5 lb / sq ft
Yes, provided you can protect the mirror surface from debris which may blow against the surface, scratching it.
Quantity discounts are automatically calculated using our online price calculator. If you are ordering qty 50+, please contact us for a custom quote.
Shipping discounts are automatically calculated using our online shopping cart.
We recommend using a backing with low thermal expansion, such as aluminum.
Please send us a diagram in JPG or PDF format and we can quote the shape for you.