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Handful of Apple Vision Pro units develop identical crack in cover glass (macrumors.com)
63 points by bcarroll22 847 days ago
12 comments

>> The reports all mention that the crack became visible suddenly and for no apparent reason, after the headsets had been connected to the external battery pack and stored overnight (some in Apple's Travel Case) with the soft front cover attached.

It is glass. The device was being charged, which means some heat gradient between the charging battery and the outside world. That thin 3d-shaped glass cracks under thermal stress should be no great surprise.

> That thin glass cracks under thermal stress should be no great surprise.

Actually, the thinner the glass is, the less likely it is to crack due to thermal gradients. It is thicker glass which experiences greater stress. The equation for thermal stress is:

thermal_stress = (coefficient of thermal expansion) ∙ Young’s modulus ∙ ∆T

which for glass, works out to about 0.63 MPa per 1 degC temperature difference between the centre and edge of the glass. Thinner glass has less temperature difference, so lower stress. Furthermore, surface roughness and type of imperfections lower the amount of stress needed to cause a failure, so Apple's obsessive polishing makes the glass withstand higher stress than usual.

Thanks for the info and model! But if the thin glass is bonded to the aluminum frame by glue, would that not change the calculus? If we imagine hot air on one side of the thin glass and cold aluminum on the other?

I’m very skeptical of the “charging thermals cause cracks” theory, seems more likely that minor manufacturing defects might do so when the headset cools from a session. But I suppose we’ll hear more than we want to in the next few weeks.

> The device was being charged

The external battery pack is the only battery, there is no internal one being charged. There is also no mention of the external battery being charged.

Maybe no surprise to Apple, but it is certainly a surprise to the purchases who shelled out $3,500.
> Maybe no surprise to Apple

It would be a huge surprise for Apple if a lithium battery inside the visor caused the cracks, as they did not design the head unit to include any internal battery.

There isn't a significant battery inside the visor. Unplug the external battery pack you keep in your pocket and see what happens.
I would need someone else to tell me because I'm not buying a $3,000 toy.
Maybe they placed the visor near or on top of the battery while it was charging?
There's no battery behind that glass, so it's the processors or another component generating heat while stored.
> Given that the battery is external to the headset, any heat generated would presumably need to be caused by a background software process gone haywire.

Apple is very good at background software processes taking 100%-500% cpu (100% == one core in Apple land).

>> The reports all mention that the crack became visible suddenly and for no apparent reason, after the headsets had been connected to the external battery pack and stored overnight (some in Apple's Travel Case) with the soft front cover attached.

The battery is external, but mobile. The users may well have stored it inside the thing. Plus, it is understood that this device continues to draw power while not in use, which also suggests a possible thermal gradiant.

IIUC there's no lithium battery inside the Apple Vision Pro at all. The power for it is supplied by an external batter connected via USB cable.
If it had cracked while in use, perhaps due to the processors heating, but the battery is external to the device, so I don’t see how that’s relevant. I suspect a manufacturing defect personally, given that the heat comes from the computer inside and not the battery.
It would never occur to me to store the device connected to its battery inside the case — or outside the case, for that matter.

I don't like the idea of that dense, heavy battery potentially getting displaced from the holding strap in the case cover and banging around inside against the Vision Pro.

Since I got mine February 2 I've kept both my batteries attached to chargers when not in use.

The Apple case has safe stowage for the battery. It is categorically not going to be banging around if you secure it in the case properly. I've taken mine to work frequently since release and have not observed it coming loose.
Fair enough; good to know.
Well, you probably didn't read Apple's instructions then :-)
Correct
Steve Jobs would have responded with "you're wearing it wrong."
He didn't say this. Wired, however, did.

If you go to the source, Apple/Jobs took accountability. But Wired got clicks.

> He didn't say this. Wired, however, did. If you go to the source, Apple/Jobs took accountability. But Wired got clicks.

I think you got most of this wrong. The "you're holding it wrong" meme started on MacRumors, not Wired. MacRumors forum user samcraig emailed Steve Jobs about the low signal issue he (and many others) experienced while holding the new iPhone 4 in a specific way. He asked "Question - What's going to be done about the signal dropping issue. Is it software or hardware?"

Steve Jobs himself emailed back to samcraig:

> Non issue. Just avoid holding it in that way.

He also later responded back with the following statement. This was the first "official statement" from Apple at the time, sent to tech news outlets.

> “Gripping any mobile phone will result in some attenuation of its antenna performance, with certain places being worse than others depending on the placement of the antennas. This is a fact of life for every wireless phone. If you ever experience this on your iPhone 4, avoid gripping it in the lower left corner in a way that covers both sides of the black strip in the metal band, or simply use one of many available cases.”

So literally neither Jobs, nor Apple, took any accountability.

Screenshots of that email exchange with Steve Jobs are still available online[0]. Furthermore we don't have to doubt the veracity of the screenshots because just one week later, Apple PR disputed[1] a different fake email chain with Steve Jobs, but Apple PR never disputed this email chain, publicized only one week earlier. If it was fake, they would have told outlets it was fake at the time.

0: https://www.macstories.net/iphone/steve-jobs-on-iphone-4-rec...

1: https://techcrunch.com/2010/07/01/steve-jobs-emails-fake/?gu...

This is the story that made the phrase catch on, note the URL:

https://www.wired.com/2010/06/iphone-4-holding-it-wrong/

I find a contemporaneous account of your backstory here (edit: your edited in MacStories link points to this):

https://www.engadget.com/2010-06-24-double-stevemails-on-iph...

Which does contain your quote*, and is indeed a day earlier than the Wired story that got wide coverage.

However, the meme quote that is repeated today is from the Wired headline.

* Attributed to "Tipster" Rory Sinclair and his posterous blog.

Ah, I see. "Just avoid holding it in that way" vs. "you're holding it wrong"
Apple has (wrongly, IMHO) gotten a lot of flack over this.

People forget that at the time, there were a number images circulating around from instruction manuals for Nokia and BlackBerry phones that explicitly mentioned the same thing.

Yes and I felt Apple also wrongly got *flak about down-tuning some CPU performance settings when batteries start getting older. The same year that story went crazy, I had a Samsung Galaxy with a fairly used battery. Once it reached 25% capacity or so, it could still chug along fine for another several hours if you didn't do anything CPU-intensive. But drawing too much current from the battery (video/games/etc) would steeply drop the output voltage of the battery, and result in the phone instantly shutting off entirely. It was unlikely to successfully boot after that, because the boot sequence had a short stage that hit nearly 100% CPU utilization before power management kicked in.

Note that "25% capacity" is usually calculated from steady-state output voltage. The voltage of a battery generally drops slowly as it gets used. But when the battery gets older and its internal resistance increases, it can no longer output the same current at lower voltages. The energy is still there, but can only be accessed either by sipping it slowly for a long time at a useful voltage, or pulling the energy out quickly at a uselessly low voltage.

So two solutions could be: Let peoples phones randomly die sometimes at 20% charge. Or set 25% to "0%" and never let anyone use those extra few hours for idle texting/etc. Or throttle the CPU after the battery falls below 50% so the phone can't cause fatal battery voltage drops with short bursts of high CPU utilization.

I thought Apple made the right choice for consumers, it's the solution I would have wanted on my Samsung, and I was jealous iPhone users didn't have to deal with a phone that said "25% full" but could randomly shut off at any moment in your pocket or hand without warning.

*I believe it is flak, not flack.

Nokia and blackberry didn't expose the metal antenna bands directly so a user could short them. That was the main issue introduced by the iPhone 4s metal antenna bands on the outside.

Later this was resolved by having multiple antennas but the original 3G spec didn't allow this. These days with MIMO multiple antennas may be active.

The actual quote is “Just avoid holding it that way.“

Which is like Frank Lloyd Wright’s answer to a leaky roof at Fallingwater: “put a bucket under it.”

You're seriously going to quibble about "Just avoid holding it in that way." v. "You're holding it wrong." That's some petty shit right there. I suppose not surprising with how this forum has deteriorated over the last decade or so.
not convinced Jobs would have produced $3500 AR ski goggles with a pocket battery pack
^^^^^
Weird. JerryRigEverything showed that the cover glass is actually plastic. It's got way too low scratch resistance to be glass. And plastic shouldn't crack like this.

Maybe only the top layer is plastic?

not accurate. the cover glass is wrapped in plastic. it's a glass sandwich with plastic as the bread. it is glass.
Ah I see. But I wonder why they went for this. Why put the most scratch-sensitive material right on the outside? This way you get all the negative sides of glass (high weight, cracking under pressue or impact) while you get none of the benefits (scratch-resistance).

And in this case the side of the material that's exposed to the user is plastic. Why would Apple brag about it being glass if the user can't even notice it? :)

What a disaster of a product. This isn’t a true Gen 1 product in the sense that the iPhone was. Apple waited an entire decade after the Rift was released, and released a headset that didn’t leapfrog the industry in any meaningful way. Steve Jobs would have shitcanned this months before the announcement and told his team to go back to the drawing board. Do I think that 5 years from now Apple will have a worthwhile product at a reasonable price point? Maybe. Maybe not. But to expend all that social capital on a device that sucks is really destructive to the brand, as is the insistence that it gets to collect tens of billions a year in rents because it owns the most popular computing platform for most people.
Curious those who bought it a few weeks to a month ago... are you still using daily and how?
I am. It has essentially become my favorite computer for general "puttering" -- watching content, light browsing, messaging. Whereas before maybe I'd curl up with my mac in my lap in bed, or doom scroll on my phone, I now use it, and it is far more enjoyable and comfortable.

For FOCUSED work at my job, where I really want no distractions and to just stare at something for a while and work deeply on it, it has been nice to use it as a replacement monitor. But, for general work, I still prefer my "normal" two-screen monitor setup at work, since it is easier to task-switch and go talk to people and come back, and AVP doesn't yet support multiple monitors.

cool and have you previously used VR headsets prior and frequently too?

Im interest in developing bunch of ideas for it and as soon as it shrinks down to glasses size and or close ...it or one of it's competitors becomes the next iPhone.

Meta Ray Ban's seem to be selling well and all they do is reliably and solidly take pics and live video. A dataset to show people want smart glasses as well how many people in the world wear some type of form of glasses and also like taking pictures? I love my Meta Ray Ban's i bought in October.

Have had several VR headsets, ranging from a Vuzix way back in the day to the Valve Index and Q3. This is the first one where I have actively OPTED to use for something other than gaming. The one thing I’ll knock is that other devices I’ve owned have been more comfortable (notably the Valve Index, which out of the box has had the best comfort of any device I’ve had, although I cannot use it lying down/on the couch because the head strap is so bulky).
are you a bot? you seem like a bot. I've been watching you and you're very bot-like. tell me otherwise.
You are entitled to your opinion. I don't have the time nor the will to engage with your concerns.
My neck, my back, my Vision and my crack
Feels like some 2000s hip hop lyrics
https://www.youtube.com/watch?v=bW92agO2NxY (explicit version, of course - the only real version)
Side rant about Apple. I never understood why Apple took such a hardline on offering repairs and charging so much for them. They are one of the most valuable companies on the planet and they have always squabbled over repairs.

They went through such great lengths with their sensors about detecting water damage to iPhones that prevented people from getting legitimate repairs done that had nothing to do with water damage.

Come on Apple, do good faith repairs. You can afford it. People already love Apple products. Repair your stuff without treating everyone like a criminal.

Now we know why Apple does not sell to EU yet, where there is a 6 month warranty by law for most goods.
It's not a warranty, It's that the seller is responsible for any manufacturing defects, and in the first 12 months(6 months in the UK) any defect is presumed to be a manufacturing defect automatically unless the seller can prove otherwise.

After that time the seller is actually responsible for 6 years after the original sale, but the responsibility is on the buyer to demonstrate that a fault is a manufacturing defect.

Why would that matter in this case? Apple has a 12 month warranty on this and most of their other hardware. Also, I expect most people shelling out $3500 for a headset are going to get AppleCare+ which also covers accidental damage.
AppleCare users are paying hundreds of dollars for this fix.
Why is it glass with a plastic coating instead of solid plastic? Apple's use of glass has to be part of a scheme to make money replacing glass parts.
But plastic easily scratches? The real question is why it is plastic over glass instead of plastic under glass. Though, I'm kind of thinking they might have realized this could happen and so wanted to safety of the plastic in front of the glass lest users accidentally cut themselves on the broken glass :/.

https://youtube.com/shorts/kuiwxZS4GJE

https://youtube.com/shorts/5Wsmz7sjOb4

I wear glasses and every lens I've ever owned has been some type of plastic. Yes small scratches add up over a year but it isn't that bad. The coatings they have do a pretty good job to reduce scratching.

Apple is using thin glass covered with a soft plastic. Why possible advantage could that ever have over solid plastic with an anti-scratch coating?

You have to actually then coat it with anti-scratch coating, you have to make sure people carefully clean the device in ways that don't destroy this coating, and the result--as you admit--still gets scratched, and routinely it is these scratches that cause me to eventually get new glasses. I don't think "treat this device with the implicit care that you treat your primary pair of glasses" is fair, as even if I carry around a second pair of glasses they tend to get scratched as they don't have any of the automatic protections my primary ones do (due to being on my head or only put down for limited periods of time).
It feels cool to the touch and therefore feels more "high quality" than a plastic would.
Yeah, it makes sense for phones, since the touchscreen feel affects perception of quality. But this is literally just a gimmicky non-touch display and didn't need to be real glass
Maybe it has desirable properties compared to plexi.
Polycarbonate would be a better choice than plexiglass/acrylic. What advantages does glass have? More likely to break and more repairs?
scratches. its all about scratches.

any poly will scratch pretty easily compared to glass, which is a bad thing when its a lens you are looking through. You could make the argument they could just design an easily replaceable poly lens at a reasonable price, but.....its 2024 device manufacturers hate the idea of any user replaceable parts.

JerryRigEverything did his usual scratch test with an AVP and the "front glass" scratches with picks of Mohs hardness 3... What kind of poor quality glass is this? Maybe it's just the coating that failed?
Do you wear glasses or know someone who does? Most of us have plastic lenses with an anti-scratch coating. It works pretty well.

What advantage would there be to switch from plastic lenses for practical items like glasses to glass lenses with a thin soft plastic coating?

I don't, and the couple people I'm close to that do have glass lenses. But, my sample size is pretty bad.

I legitimately didn't know it was that common; I had to switch to glass lens non-prescription sunglasses a few years ago because even the upper end plastic ones weren't durable enough for me.

The part that is cracking is plastic on the outside glass on the inside, it doesn't get the scratch resistance benefits.
You don't have to have a full cover.. Only the cameras would need to have a window of (sapphire)glass. The rest of the ski-mask could easily be plastic, as it's only used to display eyes.

My guess is that it gives them a few cycles to improve the weight. The iPhone X was a monster in terms of weight

Polycarbonate is better in some ways but more susceptible to scratches than plexiglass. Glass is great because unlike the plastics it is UV resistant.
Polycarbonate is great for UV resistance, though not sure that matters for something you use indoors. I’ll grant you scratch-prone.

There are additives and coatings for everything now, and the glass Apple is using is also highly engineered so you can get just what you want no matter what. I’ll bet it comes down to feel and consumer experience.

Only with a UV film installed to protect it. I think all plastics degrade under UV light and polycarbonate is no different. It will yellow and lose it's strength with unprotected UV exposure.
Solid plastic is cheap. It’s the same reason the body is aluminum and not some plastic.