Sapphire vs. Gorilla Glass
Will sapphire cell phone screens be the next big thing?
At Guild Optical Associates, we work with sapphire all day, everyday. Sapphire is a very scratch resistant material. It is also much stronger than many optical substrates.
As most people know, diamond is the only thing tougher. Just to give an example: Sapphire has a modulus of rupture of 65,000 psi and registers as a 9 on the Mohs hardness scale. Fused silica/quartz, (glass), only has a modulus of rupture of 7,000 psi and measures up to 7 for Mohs hardness . For those who are unaware, modulus of rupture is the measure of flexural strength before a product breaks and Mohs hardness is a scratch scale from one to ten, diamond being 10.
Simply stated, these numbers show that sapphire is by far the strongest of the aforementioned materials. There has been a lot of talk about the possible changeover from gorilla glass iphone screens to sapphire screens. Sapphire has already been transitioned into certain aspects of the popular cell phone. The protective window over the camera lens and now the home button are made of sapphire.
Some of the articles and videos online have gone to extremes however, stating that the new sapphire screen phones will be indestructible or impervious to drops and extreme impacts. Some people think that the sapphire screens will be less breakable than gorilla glass screens. Actual lab tests have been proving this rumor untrue however. While the sapphire is more resistant to scratches, like gorilla glass it is not shatter proof. Tests have in fact shown that unscratched gorilla glass screens may be more resistant to shattering than their sapphire competitors.
This is most likely due to gorilla glass’s ability to flex.
Still, there are other factors to mix into this sapphire vs. Gorilla Glass discussion, more than will fit into this article. For example, scratches, and how they measurably affect the flexibility of the gorilla glass without breaking . A simple scratch down the middle of a gorilla glass screen could cause it to crack along that scratch given the right type of impact. Where as sapphire would most likely not receive that scratch in the first place, possibly making it stronger against the same type of impact.
How will this all weigh out? Guessing we will just have to wait and see…
Whether sapphire screens will work out for smart phones or not is undetermined in real world testing. However Guild Optics does know that it performs better than any other optical material in extreme conditions. Harsh sandy conditions, extreme pressure differentials, under ocean depths, demanding medical applications, and temperature sensitive uses. Sapphire’s resistance to scratching means consistent strength and transmission throughout the life of the window or lens.