Sounds like a great application for an e-ink display. No burn-in, low power, and can always emit as much light as the keys on the keyboard do (by front-illuminating the bar when the keyboard backlight is on).
The 2014 ThinkPad X1 Carbon had an e-ink touch strip instead of an F-row (exactly like the MBP does). It didn’t work very well: poor display contrast, hard to see in bright daylight, can’t feel for keys, slow response time, etc. They switched back to real keys for the 2015 model release.
...that’s why Apple’s adoption of it surprised me the most: I saw how it on the ThinkPad added no value, and while Apple has greater integration and will undoubtedly encourage third-party devs to use it - it will still be too fiddly and complicated.
I think Apple’s too proud to kill it off in just one project cycle - but I can’t see Apple’s management justifying continued investment of time into maintaining it. The fact they didn’t include it in their latest desktop keyboard (for a Pro users no-less!) says something.
It had a smooth plastic window over it without any matte-finish or anti-reflective coating. Couple that with how the keyboard area is often in the shade made it hard to see.
I owned one of those X1 Carbons and that was absolutely not e-ink. It was merely some LED lights over a touch surface. All the possible configurations were physically cut out; you couldn't display arbitrary stuff on it. Even for what it did do, it sucked, and made the entire layout more awkward.
I thought so too but the Pebble Time had snappy, colorful animations[1] that looked really good, and changed my perception completely on what is possible with e-ink.
With regards to touch feedback, MacBooks come with a pretty hefty “haptic engine” already so it should be possible.
>I thought so too but the Pebble Time had snappy, colorful animations[1] that looked really good, and changed my perception completely on what is possible with e-ink.
I see. The confusion on my part is that they used the term "e-paper" which I've now learned is an umbrella term including e-ink and any other technology that works to electronically replace paper.
Based on cursory research I believe the most important aspect of the LCD used on the Pebble time is that it's a "Memory in Pixel" or "Memory LCD"[1] – a technology specifically built for screens that may show the same thing for a sustained period of time.
Memory in Pixel seems to be a feasible alternative to e-ink if you want a low-power display that tends to show the same thing for extended periods of time. And it would probably work well for the use case of Apple's Touch Bar (assuming you can get a good pixel density with this technology).
Not entirely accurate, the Force Touch device uses a linear motor to accelerate a small mass to 'thump' into its housing. In principle it's similar to a speaker, but in implementation it's very different (a speaker voice cone never intentionally impacts its housing, for example).