iPad Pro According to John Gruber Apple Pencil doesn't need any extra hardware/sensor on the iPad Pro display

Discussion in 'iPad' started by mdridwan47, Nov 24, 2015.

  1. mdridwan47 macrumors 6502


    Jan 20, 2014
    Apparently the display is still the same as other iOS devices. The Apple pencil emits radio waves on the display to register drawings.

    I didn't know that. He isn't 100% certain either. Is it true?

    Listen from the 7:20 mark.
  2. Fuchal macrumors 68020

    Sep 30, 2003
    If it's true then it would work on an iPad Air as long as the Pencil is on, since the iPad doesn't care it's a Pencil. Does it?
  3. mdridwan47 thread starter macrumors 6502


    Jan 20, 2014
    That's what I'm thinking.. It should work on iPhone 6 too..
  4. KPOM macrumors G5

    Oct 23, 2010
    It doesn't work on any other iOS device. The iPad Pro scans at 240hz when it detects the Pencil, which reduces the latency and improves the accuracy.
  5. drz macrumors newbie

    Aug 25, 2015
    Does that mean the display's refresh rate is 240hz? I find that hard to believe, but would be cool if it was true.
  6. bcaslis macrumors 68020

    Mar 11, 2008
    He's speculating. In Apple's own iPad Pro video they talk about making the display different to have a more accurate digitizer. There is no way it's the same as other iPads.
  7. Phonzoxd macrumors 6502a

    May 28, 2013
    So hes wrong? I dont understand, why dont he just test it on any other ios device?
  8. bcaslis macrumors 68020

    Mar 11, 2008
    It's already been tested by many on other iPads. It only works on the iPad Pro. Just like Apple says.

    And to be fair to Gruber, the OP is misinterpreting. Gruber in his podcast speculates that the Pencil uses radio. But he never says it works with other iPads.
  9. modernaccord macrumors 6502a

    Apr 20, 2015
    Seattle, WA region
    I believe he's trying to say that the Apple Pencil would theoretically work on other iOS devices, but the iPad Pro has a more advanced display so that the pencil can be accurate and interface with it. An iFixit teardown of iPad pro did reveal an extra chipset for Pencil input, so obviously there's something going on.

    I'm sure getting the Pencil to work on other iOS devices isn't too hard, but it would require additional hardware to be built into the device.
  10. mdridwan47, Nov 24, 2015
    Last edited: Nov 24, 2015

    mdridwan47 thread starter macrumors 6502


    Jan 20, 2014
    I said verbatim,

    "I didn't know that. He isn't 100% certain either. Is it true?"

    I didn't say that he said it.
  11. aevan macrumors 68030


    Feb 5, 2015
    John Gruber is a smart guy and his podcasts are great but he is not, in fact, that tech savvy and he's most likely wrong about this. The Pencil is not capacitive so there must be a different tech inside the iPad itself that detects position.
  12. KALLT macrumors 601

    Sep 23, 2008
    Obviously the touch screen must have the capacity to register/receive the input of the Pencil. There is not anything in other iOS devices that would be capable of doing this and we also know that the touch screens of these devices are not nearly as precise to make this work. The Pencil alone is not doing anything on these devices that could not be replicated by an ordinary stylus.

    Because you cannot rule out that way that it is technically impossible to make it work. Apple is known to artificially restrict features with software. It seems that nobody outside Apple knows the secret yet.
  13. AceFernalld macrumors 68000


    Mar 3, 2008
    If there wasn't additional tech in the display, why are Pencil touches registered before contact is made?
  14. mdridwan47 thread starter macrumors 6502


    Jan 20, 2014
    According to Gruber, Apple pencil emits radio waves on the display to register contact.
  15. AceFernalld macrumors 68000


    Mar 3, 2008
    Hmmmm... Interesting. I want a full technical breakdown of how this all works, some really fascinating technology and 'insanely great' execution if I do say so myself.
  16. Rogifan macrumors P6


    Nov 14, 2011
    Gruber doesn't know he's just guessing.
  17. LunaC macrumors member

    Feb 26, 2011
    A regular old Samsung S5 can have the sensitivity turned up so that a regular #2 pencil will work great, nothing special needed as it is in the settings. I wanted to see if I could discover how via BT to initiate the other mode on the iPP but now someone else will have to.
    Ive wondered if a regular iPad could be done the same way for a long time.
  18. Atomic Walrus macrumors 6502a

    Sep 24, 2012
    Tech journalists don't understand tech, shocking.

    What you have is an active capacitive system. The digitizer itself is still a traditional capacitive touch digitizer (like N-trig), but the pen emits a distinct signature the digitizer will detect.

    The digitizer itself polls at 240hz, this has nothing to do with LCD panel refresh rate. This is likely a hardware improvement over the older capacitive digitizers and probably wouldn't work on older hardware.

    The capacitive digitizer grid also has greatly improved linearity and accurayc, most likely due to an increase in density. This is also a hardware change.

    Now to address the issue: Yes, the existing digitizers could likely be adjusted to read the active capacitive signal of the Pencil, but they would have a lower polling rate AND significantly worse linearity/accuracy than what we see now. Performance would be quite a bit worse, which would make the whole system look bad (like N-trig) and of course eat into Pro sales.
  19. ozthegweat macrumors regular

    Feb 20, 2007
    No, the display scans for Pencil input at 240Hz. Normal touch input is scanned at 120Hz. Screen refresh rate however is most likely 60Hz, as a higher refresh rate is usually not noticeable.
  20. DarwinOSX macrumors 65816

    Nov 3, 2009
    Gruber is wrong. Kind of surprised he didn't know this already.

  21. NT1440 macrumors G4


    May 18, 2008
    The rate varies, and Apple has that timer coalescing chip which was first made for the 5K iMac, now in the iPad Pro.

    So this isn't simply a case of the screen being the same, there is much more to it that makes the pencil work.
  22. dyt1983, Nov 25, 2015
    Last edited: May 23, 2018

    dyt1983 macrumors 65816

    May 6, 2014
    edit: to remove personally identifying information not relevant to the thread.
  23. Atomic Walrus macrumors 6502a

    Sep 24, 2012
    A higher refresh rate is extremely noticeable with moving content, but there are currently very few IPS panels capable of 120hz refresh. Getting anything out of it also requires hardware that can put out 120 frames/sec

    The old claim that humans can't tell the difference between 60fps and higher was based on a study with very poor methods and is clearly absurd to anyone who's seen higher frame rate content.
  24. Atomic Walrus macrumors 6502a

    Sep 24, 2012
    **Sorry about the double post, meant to combine this into the post above

    The version I've heard is that the tilt detection works by having two emitters in the pencil. One is in the very end of the tip (in the little "ball" at the end of the cone) which is how it can actually detect the position of contact without offset at any angle (this is also why the tip is a bit larger than the SP4 pen, which has the emitter in the pen itself).

    The second emitter is farther up I the pen. The digitizer compares the two signals to determine tilt. This is why you can mess up tilt detection by having your finger too close to the tip on screen.
  25. haruhiko macrumors 601


    Sep 29, 2009
    John Gruber does not know any better. It's just his guess.

Share This Page