As a quick and dirty rule of thumb measuring parts per million in anything except time or frequency will get expensive. Temperature drifts will cause expansions and contractions on that order if you’re measuring lengths.
By 1870 pi was known to several hundred decimal digits, for something like this calculation where you have other large sources of error Archimedes approximation from 2 millennia earlier would probably be fine. (<1% error)
It's unfortunate that page briefly flashes some text and goes blank
leaving an error in the browser console
Uncaught ReferenceError: TextEncoderStream is not defined
<anonymous> https://docs.oxide.computer/guides/introduction:18
Error: Minified React error #423; visit https://reactjs.org/docs/error-decoder.html?invariant=423
for the full message or use the non-minified dev environment for full errors and additional helpful warnings.
zh https://docs.oxide.computer/assets/components-BfA3Cgf2.js:40
Thanks for the bug report. We could stand to have a better catch-all error page for this case.
Looks like this browser API is used by Remix’s new Single Fetch feature, which coincidentally we just started using last week. Sorry we broke the site for you. We don’t have as clear of a browser support policy as we probably should, but if we did, I doubt we would be guaranteeing support for two year old browsers unless we had a customer request for it.
>And for those further out, where the Muntz TVs did not work, those could be returned at the customer's additional effort and expense, and not Muntz's.
What a truly awful approach to saving money. Just mislead the customer and have them pay the price associated with that. Good thing we have consumer protection laws now.
Pease the bandgap tzar, one of my professional heroes.
Muntz no. Should be filed in the same can as Sinclair. Rumour has it that the vast majority of really defective transistors (rather than just the moderately defective ones he shipped) were used as hard core under Sinclair's drive
The explanation is really well done, it captures the essence of the Pauli exclusion principle without delving too deeply into the weeds. In my opinion the best part of the video is the explanation of the "hole" quasiparticle at 6:10 (I learned this as a pseudo-particle but will defer to Wikipedia [1]).
While a great introduction to semiconductor behavior this does gloss over a very important detail namely direct vs indirect semicondoctors as some others have mentioned. In the video the detail that's glossed over relates to the nature of crystals, namely that they're highly ordered repeating structures but that they don't look the same when viewed from every direction. This means that there isn't a single band-gap but multiple ones depending on the direction of the crystal you're contemplating.
At this point you may reasonably ask why the direction matters and now we unfortunately get deep into the weeds with quantum mechanics again. When a single photon is absorbed in the semiconductor system both momentum and energy must be conserved. The momentum of the photon for something like the Silicon bandgap is quite small (something like the equivalent of an electron traveling at 1500m/s) while the momentum of room-temperature conduction electrons is substantially faster [2] so as a very slight simplification transitions due to the absorption of photons are not accompanied by a change in momentum and so we only care about the band structure (and the accompanying free carriers) associated with a particular crystal direction.
In particular in Silicon you have what's called an indirect bandgap, namely the minimum energy conduction band electrons have a different momentum from the valence band holes ([3]) and as a consequence while you can _absorb_ a photon in order to make a detector you cannot make it efficiently _emit_ a photon as an LED should (something the video got wrong).
None of this matters for the heart of the video, which focuses blue LEDs in the GaN materials system which is definitely a direct bandgap material, however if someone does manage to create a manufacturable light emitter in pure Silicon expect an absolute revolution with regards to optical computing and photonics. (Not for lack of trying, this has been the holy grail for at least 20 years, possibly longer)
Thank you. That seems to be it. I don't think it's perfect, but it seems like a hell of a good improvement on the touch interfaces car companies try and come up with today that takes into account that a driver wants to use muscle memory and not stare at the screen.
Funny story, that demo only exists because the designer was mis-categorized as a software engineer after an acquisition by Apple. After nearly getting the person in question fired it ultimately resulted in a successful job category change for them.
From the paper it looks like most of the interesting work with the laser and optical train use an external board to recreate the feedback and control circuitry already present and required for normal operation in a DVD/BluRay drive. It would be great if you could have more control over the existing hardware in these drives.
I found a project that started the reverse engineering process on a popular bluray drive [1] but it really looks like an uphill slog against undocumented CPUs and motor control chips among other obstacles. Anyone know of any other resources for reusing the existing hardware but modifying the control software?
From memory the most applicable prior art is the "region free" firmwares for various DVD drives and, the drive hacks used to play "backup" (and some homebrew) games on the Xbox 360 while bypassing some of the attestation protections for online.
> It would be great if you could have more control over the existing hardware in these drives
You can blame the DRM lobby basically forcing manufactures into a veil of "security by obscurity"
Hackaday has featured a couple of projects featuring the ps3 optical pickup unit. The author of one of the projects breaks out the 40-pin ribbon cable and is able to drive it with some simple circuitry
