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amelius

Maybe we can have diamond-based scratch protection on smartphones?

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Gorilla glass is already some percentage of "Prince Rupert's Drop" in strength.

This is not sufficient?

https://en.m.wikipedia.org/wiki/Prince_Rupert%27s_drop

It’s definitely price performant at 6.5 on the mohs scale, sapphire panels are 2-4x more expensive to produce but 9 on the mohs scales so they’re typically only found in watches I bet. At a 10 on the mohs scale diamond is still best for hardness. Maybe the same effect of the prince Rupert’s drop could be induced on a round diamond with an alpha particle beam treatment where you add these ions primarily on the surface of the stone.

I'm not exactly a watch nerd, so don't know how true this is, but I hear that sapphire shatters on impact. Or maybe that's just an excuse for people peddling "alternative" materials for their watches?

But if it is true, then I'd say that sapphire is a poor choice for mobile phones. IME I'm far more likely to drop the phone, preferably on some form of hard surface, that to scratch it. Phones are nowadays so ridiculously big, that there's zero chance I'll have anything else in my pocket.

I believe Apple tried to get sapphire for phones screens at some point, but their supplier folded.

They did however manage to get Sapphire on the watch display (at least on the stainless steel LTE edition of the apple watch series 4 and 8, which I'm aware of).

The difference between my watch (which was 4 years old at the time) and a colleagues almost brand new apple watch (without the sapphire) was really telling, is his was lightly scratched on the edges despite him being quite careful, and I was exceedingly reckless with mine as I considered it old- yet there was not a single defect.

That was a major reason for me to upgrade to the LTE of the next version of apple watch that I bought.

I have a Series 5 with the Saphire glass but my clumsy ass dropped it in the kitchen onto a stone floor. The edge of the glass shattered and while I still use it to this day, it's an ugly reminder of my clumsiness. The repair offer from Apple was to get a new one with a very slight discount.

Long story short, it is more scratch resistant but also more prone to break. So be careful.

Thanks for the warning!

I suspect the edges are more at risk than the face, as I've struck the face very hard against the edge of a scaffolding pole and there was no damage - which, actually shocked me a lot based on the force.

I wonder if they could put in tiny reaction wheel gyroscopes (to make it land in a safe orientation) or tiny linear reaction masses, or perhaps tiny replacable airbags or tiny sodium azide NaN3 charges/nozzles to blow air just before landing, to make for a gentler landing, replacable of course.

Tiny replacable airbags, on the corners. Preferably it should somehow detect the elasticity of the surface its falling to or going to hit.

There was a prototype design that a German student, Philip Frenzel, produced in 2018 that used the accelerometers to detect freefall and push out little spring claws to protect the device. It was supposed to be in production circa 2019 I think but I can't see evidence that it made it. YouTube has videos.

The sapphire on the Apple watch was a marketing gimmick, barely better than gorilla glass: https://www.youtube.com/watch?v=RF72hGIdrG8&t=10m20s

But there are other devices with better sapphire that actually live up to the hype.

Well, maybe.

I have now had watches for 10 years without issue and my phone displays seem to scratch.

I’m not doubting you’re correct, I never boight it for this reason, it was just an interesting retrospective observation. Clearly its working for me, and I’m not sure I have anything with gorilla glass.

Unless the Pixel 7 has it.

EDIT: My Pixel 7 does have gorilla glass indeed and it has two scratches on the display despite being extremely rarely used. (its my work phone and sits on my desk mostly)

From what I remember, it was mainly because it was a fair bit more expensive to manufacture.

Diamonds also shatter. It's got roughly the same toughness as sapphire but the cleavage planes are more annoying (in that it has them, while sapphire doesn't).

The threat isn't so much scratching it in your pocket (but that is possible, I typically have my sunglass clip in the same pocket--it's supposed to be in it's own case but in theory something could happen) as scratching it against things.

also note that Mohs is a qualitative ranking rather than a linear scale. Huuuuuge difference in hardness at the top end.[0]

[0] https://geology.com/minerals/photos/mohs-vickers-comparison-...

gorilla glass with olephobic layer would be really helpful unless am missing some product that has already implemented this.

Gorilla glass is easily scratched by sand, whereas sapphire or diamond stays flawless for decades.

I wonder if the process would be cheaper than the current high end (smart)watch and lens practice of sapphire coating?

No, it's substantially more expensive. At least for anything too large to just cut out of HPHT chunks, just due to CVD at optical grade being pretty slow.

Diamond coated glass is available and is sometimes used for checkout lane scanners.[1] It's not common.

[1] https://www.diamonex.com/wear-resistant-glass/

Don't we already have good scratch protection? Cracks from drops seem like the main issue.

So scratching definitely still happens, both on sapphire camera lenses and new scratch-resistant screen technology. I’ve mainly had it happen with concrete. I think concrete sometimes just has some rocks in it that have a very high hardness because I’ve gotten pretty thick scratches in new iPhones when they’ve taken a slide over a rough concrete sidewalk due to a drop while walking.

Aren't both the lens and the screen are resilient to steel/metal scratches? I'm not willing to run keys or a knife over a phone on purpose.

I've similarly experienced bad scratches whenever my phone and my keys come into contact, hardened steel may still be able to cause scratches?

Your keys are by no means hardened steel. If they are steel at all (most are brass or silver/zinc), they would be mild steel. If they were hardened they would be really difficult to cut. The harder you make a steel the more brittle it gets. Think about what happens when you slam a file with a hammer vs a large nail.

Considering how easy it is to break keys in the lock, I'd say they're definitely more brittle than malleable?

I think that's mostly from mild work-hardening, I haven't experienced that with a brand new key.

What kind of material are your keys and locks made from? Over here nickelsilver or nickel plated hardened steel is common for keys and a combination of brass, steel and titanium for locks.

This should not be possible with any type of modern phone screen. Do you perhaps have a plastic screen cover that is scratched? Or key metal could be deposited on the screen and just need to be scraped off

Depending on your location and lifestyle, your keys and other possessions can easily collect a dusting of tiny sand particles. Quartz in the sand can scratch most types of glass.

No cover, just straight up gorilla glass victus.

And it's not just key metal deposited on the screen, there are deep grooves cut into it.

I believe you, but there is some other explanation here- it warrants further investigation. You can scrape a regular glass window (about MOHS 6.5) clean with a razor blade (about MOHS 6.0) and it is impossible to scratch it, just from that tiny difference in hardness. I do this all the time, e.g. recently to get paint that my kid painted on the house windows off.

Your brass keys should only be about 3.0, and gorilla glass a 9.0- you should be able to rub keys into brass dust all day long and not mark the screen.

I store my keys right in my pocket with my glass iPhone SE, and it doesn't have a mark on it.

I suppose it is possible you have keys with some weird material or coating, or as another poster suggested- maybe something like an abrasive dust got stuck on your key.

I think you may be onto something here. Taking apart old machinery I have often observed that the hardened part of a shaft is worn and has a noticable groove detectable with a fingernail. However the part that rubbed on it is often much, much softer eg a rubber oil seal. My theory is that the much softer material is so soft that microscopic inclusions of something much harder (grit?) are caught in the material and then abrade the harder shaft. Something similar may be occurring in the keys on glass case?

Cutting with a lubricant and grit is super effective. Silicon dioxide, that is sand, is everywhere.

Brass? Who said anything about brass?

Typical keys are made from nickel plated hardened steel and nickelsilver. Considering the shiny coating is long gone and the keys are ferromagnetic, I assume it's the first. The keys are certainly hard enough to scrape my glass ceramic stove.

And reports online say that gorilla glass victus is the mist scratch prone gorilla glass, scratching at or around 6 already :/

No, it's possible on modern phone screens. My Pixel 8 Pro has Victus 2 (AFAIK), which scratched very easily from fingernails alone.

I love going to the beach, and find that modern phones still scratch easily with sand.

And it's a tradeoff. I found out the hard way that newer Pixels have incredibly soft screens to avoid cracks and shattering. Unfortunately, they're so soft that a fingernail (a 2.5 on the Mohs scale) will leave huge gouges quickly. Fortunately, there's third-party covers that use an adhesive that fills in the scratches well.

That's a little hard to believe. There are resin finishes that are hard to scratch by fingernail.

Think about it; you couldn't put a fingernail scratch into a cheap soda glass beer bottle. Why would Google make a phone with glass that could be scratched by a nail, let alone easily? Does that even exist? Perhaps there is some coating on the glass you didn't remove and that's what you're scratching?

I'm sorry if you don't believe it, but it really happens. The "coating" would have to be pretty thick, this gouge was something you could easily feel with your fingertip. I was very careful to not let my keys or anything else get near it, and the gouge (which was essentially the only scratch on the otherwise flawless screen) was exactly where my thumb hits the screen.

My Pixel 4a, meanwhile, was in my pocket all the time and never got a scratch.

I’m surprised no one has mentioned the ending of 2061

https://en.wikipedia.org/wiki/2061:_Odyssey_Three?wprov=sfti...

It's possible, and I remember seeing a very expensive prototype for it, but sapphire is already Good Enough for almost any cause of scratching you're likely to find.

We already have sapphire

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