The Macbook Has a Sensor That Knows the Exact Angle of the Screen Hinge
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The discovery of a sensor in MacBooks that detects the exact angle of the screen hinge has sparked creative ideas and discussions about potential uses and applications.
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Sep 7, 2025 at 11:20 AM EDT
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There's decent reasons to over-engineer some of these sensors so they can't be unduly tricked by external influences.
I've never once had a Dell/HP/Acer/Asus with a reliable lid close sensor. You can't trust those things.
Presumably he meant the laptop didn't go into standby when closed or woke up from standby while still closed.
Halting power until an external physical event seems like a simple enough idea. I have never wanted to close my laptop and let it keep number crunching.
Just want to warn other readers: Not all framework models have S3 sleep. I've got the 7040 AMD framework laptop and it only does s2idle.
???
I don't think I've seen a laptop that doesn't have closed lid detection. At the very least it's common enough that windows has a setting specifically for it: https://www.tenforums.com/tutorials/69762-how-change-default...
It's maddening that only Apple gets this right 100% of the time, and it's among the things keeping me on Apple's platform for the moment. I can't fathom why this isn't a bigger priority for everyone else: much like "trackpads that don't suck", it's a huge quality-of-life thing which keeps tons of people on Macs because they want it to Just Work without ever thinking about it.
That's due to "connected standby"[1], which is to have laptops behave more like a phone when in sleep. This is in contrast to S3 sleep, which basically halts all activity. Sounds all good in theory, but as soon as you allow code to be run while in sleep, it's easy for some runaway app (OS or third party) to eat through your battery even while your laptop is "sleeping". Worse is that there's no way to force sleep, so your only choice is hibernate, which is even worse than S3 sleep before.
[1] https://learn.microsoft.com/en-us/windows-hardware/design/de...
Source: My macbook has drained its battery flat while closed in my bag dozens of times. Then it just stopped doing that on an OS update. I still have no idea why.
There’s also wake on LAN which if enabled can rouse the machine from sleep after it’s successfully entered a sleep state.
So anyway that killed one of my laptop's batteries. So much for supporting Internet freedoms...
Windows comes with a utility that'll tell you what process denied a sleep request, super useful.
I've actually ran into MacBooks not sleeping a few times, but it is much rarer.
It is unfortunate because back on the mid 2000s windows had the best functioning sleep code, but then they tried to catch up with iPad's # instant on and chasing perfection led to the current mess.
Much more likely is that the OS was prevented from going to sleep by some badly behaved process, or got woken up by another thing like allowing USB to wake it from sleep, where even touching the mouse can wake it - with some laptop equivalent like a ghost touchpad touch or whatever.
> Jacket zipper
> C Major scale
> Slide whistle
> Washboard
> Airlock
> Vinyl record scratch
https://nime.org/proc/meacham2016/index.html
The only thing "Apple" here is that it's not exposed as a public API.
No, it's a different method.
Edit: catalog confirms.
https://www.novosns.com/en/hall-angle-sensor-4010
There's a fun Hackaday video using the same type of part in a rotary knob + LCD control.
https://www.youtube.com/watch?v=zIrAe23f8sg
https://hachyderm.io/@samhenrigold/115159306734992780
I thought it was centidegrees but it turns out the sensor was reporting the raw degrees.
https://youtube.com/shorts/sgqTEjN5_vQ
https://youtu.be/Uivp-hvk-nk
Edit: not forgetting the classic Miles Davis door: https://youtu.be/wwOipTXvNNo
("It’s such a fine line between stupid and clever.")
https://sound-effects.bbcrewind.co.uk/
There must be a door or two in there.
This is a semantic punt from nicer to accessible.
You simply see what the author posted and people's reactions.
It also doesn't load 400MB of JavaScript or whatever.
Personally I am not a fan of the Mastodon software or side of fedi, but I have had good times on the Pleroma/Akkoma side, and it all works together.
No one knew Reddit boards and 4chan boards either; you just knew to go to /b/ or /r/funny. The other boards, the other fediverse servers, are just details that enable other subcommunities to survive. The major community will just route to a single server, and most will probably never use a second
You also don't need to know everything right away. You could make every "mistake", sign up on the flagship Mastodon instance, hear about how you should have other instances, make an alt somewhere else, maybe fosstodon because you like free software, then you hear talk of Pleroma and you look into that a bit. It's fairly common to have multiple accounts, which is good because it provides redundancy. If your instance goes down, flagship or not, you ideally still have a way to view and post. They make it easy to import/export your following list as well, so migration isn't too bad.
It's pretty similar to Matrix if you're familiar with that at all. Initially my friends and I all ended up on matrix.org, then there was some downtime and I realized how fragile it was to all be on the one main big instance, so I made several alts. Now when matrix.org goes down (just happened a week or two ago), I can still post in the group chats I'm in, and anyone else on an instance that isn't down can post, and when matrix.org comes back it'll all flood in for those people as well.
I think it can work and be successful because email was quite successful. Not everyone was on the same domain but we still manage to email each other. You could argue that gmail has a monstrously large presence and that it's harder to host your own mail server these days, but it's all still possible.
A social network with just the top 1% of the geeks would be absolutely amazing.
No ads, a timeline which isn't endless and you can actually just read. It's actually really nice! I also think the decentralized non proprietary model brings us closer to something which is becoming ever more important in this world we find ourselves in.
- isn't The Big One (defeats the point) - has a nice domain (that's your name forever) - is stable (major downtime or data loss is unacceptable these days) - is guaranteed to stick around forever (no, migration isn't solved and it will never not suck) - has rules you agree with and can guarantee you'll follow - is running the right software (no, "fedi" isn't compatible, you either run Mastodon or things will always be ever so slightly broken)
Migration is not solved, but it also doesn't suck - unless you're doing it every week nothing will break, and several people I follow have already done it and it's been just fine.
Stability is also fine - if your server is down for a couple of hours, your timeline will catch up when it comes back online, and likewise your sent posts will stay in a local outbox until they can be sent. That's absolutely no different from email or Jabber or anything else.
"Fedi" is compatible enough that I run my own GoToSocial server, which is technically still beta software, and I haven't experienced any issues following and interacting with anyone on Mastodon, Pixelfed, Pleroma and quite a few other platforms.
Would I recommend it to a non-technical user, someone who wasn't really interested in 'servers' and 'clients' and 'protocols'? Yes, although I'd suggest they just go for The Big One, as you put it. What I would say though is that this is no longer just a technology for Web nerds any longer; it's a very viable alternative to centralized platforms.
I'd love a truly decentralized model for this but fediverse isn't it, fediverse is a Hellenic League of city states where your ability to interact outside your bubble is beholden to your and their local leadership and shifting realities of protocol war jank.
If you do think my opinion is uninformed or mistaken at least know that I know many times more people who bounced off the idea for these reasons than people who actually managed to make heads or tails of this. Fwiw I don't use xitter/bsky either.
It's really not a useful platform for publicly sharing information anymore. Drives me nuts that government agencies use it for announcements like "Here's an amber alert with a twitter link, but you can't have any of the followup information because that's only for people who are logged in."
Just call it Twitter.
I wonder if Apple uses this internally at Apple stores to set the screen angle at 76 degrees.
From the description, I would've thought it meant 76 degrees from the user's PoV, i.e. slightly closed so the user would feel compelled to open it more / tilt it into their view (with their hand). The pictures show ~70 degrees from the back of the devices though, so IDK what they mean about the hand moving the screen. There's no need for interacting then, since the display can be seen from afar.
I worked at an Apple retail store during college. We were taught to put the screens at a certain angle but it was a gut feeling angle learned through practice, and not measured. More senior people would correct you if you were off.
They did mandate putting the bezel, mouse, keyboard, etc. at specific grains in the wood that were consistent across the desks though to ensure they were lined up without having to bust out a level-like device.
Overall everything was made so that retail employees would continuously clean up the displays as they walked around the store (even while helping customers without them realizing it) so that the store always felt perfect. They had a phrase for it but I forgot now, it's been almost 15 years now...
Author can submit this to the AppStore.
What it says is (emphasis mine) “it’s not exposed as a public API”. In other words, Apple doesn’t provide official documentation and hooks for you to interact with the feature, like they do e.g. with Bluetooth. Even then, while they provide public APIs to interact with paired devices, interacting with the Bluetooth controller itself (e.g. turning it completely off or on) requires private APIs.
Is it a backup if the magnet for closed lid detection fails? Is it some kind of input for the brightness sensor or True Tone? Is it for warranty investigation, that if the hinge breaks they can figure out if it was physically pushed too far, or was repeatedly slammed open and shut like a toy?
The sensor used for detecting if the lid is closed is an “angle” sensor, although really it’s an Hall effect sensor and a magnet in the hinge. If you have a Hall effect sensor, getting angle data from it is pretty much free, because the Hall effect produces a continuously varying signal, you need thresholding logic to turn it into a binary output.
Given Hall effect ICs are so cheap and plentiful there no reason to use anything else. Also given they mass-produced ICs it’s probably cheaper to buy a fully featured Hall Effect IC, because the manufacturing cost between a basic IC and an advanced IC is almost certainly zero these days.
In short, modern IC manufacturing has just made magnetic angle sensors as cheap, if not cheaper, than dump non-angle sensing Hall sensors. After all you can always use an angle sensing Hall sensor as binary switch if you want, but the reverse isn’t true, so if the ICs basically cost the same, you can expect the less capable ICs to be completely outcompeted by the more capable ICs.
I personally am surprised they don't put an accelerometer in both halves of the laptop and use math to calculate the angle based on gravity.
There are also packaging considerations when putting a hall sensor elsewhere. Packaging it in the hinge has the advantage you can use the same hinge and sensor setup in all laptop models. Packaging the sensor elsewhere means custom packaging setups for each laptop to work around all the other components in the body of the machine. Doing the extra work for packaging in the hinge once is probably quite a bit cheaper than having to constantly redo the packaging work in every new model.
If you simply move the sensor (that is already a requirement) closer to the hinge, you can infer angle based on the Hall sensor for free. You can even get special sensors that specifically measure the magnetic field orientation for the same price as the simple type.
Yes, it's completely free with just a very minimal amount of thought put into the design.
0: https://support.apple.com/en-us/121541
Apple: How did the hinge break?
Customer: I don’t know, I just opened it one day and it came off.
"I was just hitting the side of my laptop in order to go to Safari"
No longer supported because we don't use HDDs anymore.
0: https://support.apple.com/en-us/121541
Merlin[1] (also from Cornell Lab of Ornithology), on the other hand, has both image and sound ID. I haven't used either, so I cannot compare the quality of results from Merlin vs. BirdNET for sound ID, but afaik only Merlin has image ID.
0. https://birdnet.cornell.edu/
1. https://merlin.allaboutbirds.org/
Not condoning people make this app, just thinking about how fast things have moved in just a few short years.
not only for mac users.
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