With the release of iPhone, the Internet's attention to sapphire has reached an unprecedented level. That would only be used in the luxury mobile phone on the sapphire screen may gradually with the release of iPhone in intelligent mobile phone popularity for the whole industry chain, this may be a change, for ordinary consumers, maybe you are more concerned about the sapphire will bring what changes to your mobile phone.

Note that at present the sapphire is synthetic, not natural sapphire. The price of natural sapphire is too expensive, and the color / light is not uniform, there is no way to do the screen outside the cover. Even on the top of the wrist watch, the sapphire on the dial is also synthetic.

Currently in the market to see the use of sapphire screen mobile phone products before Motorola luxury mobile phone AURA, priced at more than 60 thousand Vertu Ti, and has just released the KYOCERA Brigadier mobile phone, plus has been rumored vivo has long been a new machine iPhone and That's final., the sapphire screen mobile phone is actually very few.

I asked some of my friends who liked mobile phones, and their impression of sapphire was all over the "hard glass and wear-resistant" level. This is true. If you search all kinds of encyclopedias online, they will tell you that the hardness of sapphire is up to 9, which is the hardest material besides diamond.

At present, mobile phone manufacturers are widely recognized and used the Corelle three generation gorilla glass, its main ingredient is silica (SiO2), Mohs hardness scale in glass hardness is 6.5, even if Corelle has repeatedly stressed that their third generation gorilla glass hardness than ordinary soda lime glass is much better, but expect it is not more than 7 very practical things.

It is of high hardness compared to sapphire glass logical thing, when the gorilla glass met Mohs hardness higher than 7 of the material (such as Mohs hardness of 7 silica, is what we usually say when friction sand) screen, a long time will inevitably leave traces. It also explains why a lot of people 's phone screens leave tiny scratches after a long time use.

However, to replace glass as a new material of mobile screen cover, sapphire can't win by only relying on hardness. There are still many problems to be solved with sapphire.

The first is toughness, which is very important for a mobile phone. I asked the sapphire products of domestic production suppliers "day", the company currently offers the sapphire screen in vivo has not released a mobile phone, through an anonymous employee said the biggest problem they encounter is the sapphire screen low toughness.

The toughness of sapphire is worse than that of Corelle gorilla glass. The result is that when the cell phone with sapphire screen and Corelle gorilla glass phone are subjected to the same force impact or extrusion, the possibility of breaking is greater.

Hardness and toughness are two concepts. Something that has a large hardness does not have to be tough, or in other words, a sapphire screen is more "brittle" than glass. A very easy to understand example: plastic is a very poor material, but it is particularly resistant to falling, that is, its toughness is very good.

So Apple invested GT Advanced gives a solution, they will put the sapphire material thin, the thickness of the glass gorilla three generation is generally 0.7 mm, while the GT Advanced made the sapphire screen thinner than it, at the same time on sapphire affixed to a layer of glass to form a hybrid panel. This is a bit like a sticker, which takes both the hardness of the sapphire and the toughness of the glass.

Such a way seems very funny, but it is a helpless action. It also reflects the short board of the sapphire screen currently in toughness, which is the main reason to prevent it from replacing glass.

The second problem on the technical side is the transmittance. The wavelength of visible light is 400-700 nm. The data from Corelle official show that the transmission rate of the three generation of gorilla glass to visible light is over 92%, while the transmittance of visible light at different wavelengths is quite stable. The transmittance of sapphire to visible light is less than 90%, and the transmittance of visible light at different wavelengths is circular curve.

This brings a problem. The low transmission rate means that when using sapphire to make the screen cover of mobile phone, the brightness of the screen is lower, and the imbalanced transmission rate will make the screen color.

The third question comes from the cost. Many people are saying that the cost of sapphire is higher than the cost of Corelle glass, but how high is it? According to one industry insider, before the sapphire screen, due to the complex manufacturing process, the yield was low, and the cost was almost 10-12 times that of glass. In recent years, with the improvement of sapphire process, the gap is decreasing, but it is also 7-8 times.

If the cost of a Corelle glass is calculated at 3-4 dollars, sapphire will increase the cost of mobile phone by 20-25 dollars, and the increase of these costs will be passed on to consumers.

You may be wondering why there are so many problems in sapphire, but still some vendors still think of it as a substitute for future glass.