[HN Gopher] High-quality OLED displays now enabling integrated t...
___________________________________________________________________
High-quality OLED displays now enabling integrated thin and
multichannel audio
Author : LorenDB
Score : 109 points
Date : 2025-05-28 01:53 UTC (1 days ago)
(HTM) web link (www.sciencedaily.com)
(TXT) w3m dump (www.sciencedaily.com)
| dedicate wrote:
| My mind immediately goes to VR - imagine how much more immersive
| that would be!
| globular-toast wrote:
| Slight problem being you don't hear through your eyes.
| short_sells_poo wrote:
| Easily solvable by a piece of bread soaked with a drop of
| lysergic acid diethylamide :D
|
| Ingest. Wait 30-60 minutes. Enjoy the ride.
| miguelnegrao wrote:
| For VR, since you have to put the helmet in your head, it is
| usually assumed users don't mind putting headphones as well, so
| most solutions are via headphone-based spatialization.
| walterbell wrote:
| Could such a display also function as a microphone?
| jdranczewski wrote:
| Good point, piezos do also generate voltages when deformed, so
| this could conceivably be run in reverse... Microphone arrays
| are already used for directional sound detection, so this could
| have fun implications for that application given the claimed
| density of microphones.
| nine_k wrote:
| Would a piezo crystal, mounted behind a screen and the glass
| panel atop it, have enough sensitivity to capture
| recognizable speech?
| spookie wrote:
| If you put a dualsense controller atop of glass and send
| sound through it to the back-left or back-right channels
| (controls the haptics) you definitely hear it, so I presume
| yes.
| Nevermark wrote:
| You could likely do both at the same time.
|
| The "microphone" would be the measurement of interference
| between speaker demand and actual response.
| orbital-decay wrote:
| Technically yes, piezo cells are reversible, just like about
| anything that can be used to emit sound. You can use the array
| for programmable directionality as well.
| GenshoTikamura wrote:
| A proper telescreen is not the one you watch and listen to, but
| the one that watches you and listens to you, %little_brother%
| tuukkah wrote:
| > _This breakthrough enables each pixel of an OLED display to
| simultaneously emit different sounds_
|
| > _The display delivers high-quality audio_
|
| Are multiple pixels somehow combined to reproduce low
| frequencies?
| GenshoTikamura wrote:
| Theoretically, any frequency can be produced by the
| interference of ultrasonic waves, but the amplitude is
| questionable, given that these emitters are embedded into a
| thin substrate.
| lmpdev wrote:
| Would the vibration be detectable via touch?
|
| It would be wild to integrate this into haptics
| skhameneh wrote:
| Audi somewhat did this with the display in the Q8 E-Tron. I
| don't recall if the display is OLED, but it has excellent
| haptics.
| dzhiurgis wrote:
| How does it work? You force press (remember 3d touch?) when
| you find item you after?
| api wrote:
| A laptop improvement I'd love would be a haptic keyboard. You
| could then make the entire laptop waterproof as well as do
| keyboard reconfiguration for certain tasks.
|
| I always though Apple's Touch Bar was some kind of entry point
| into that idea but it wasn't, wasn't useful, and just died.
| cubefox wrote:
| This is impressive. Though perhaps not very useful. Humans (and
| animals in general) are quite bad at precisely locating sound
| anyway. We only have two input channels, the right and the left
| ear, and any location information comes from a signal difference
| (loudness usually) between the two.
| mjlm wrote:
| Localization of sound is primarily based on the time difference
| between the ears. Localization is also pretty precise, to
| within a few degrees under good conditions.
| user_7832 wrote:
| Nit: time difference, phase difference, amplitude difference,
| and head related transfer function (HRTF) all are involved.
| Different methods for different frequency localisation.
|
| There's this excellent (German?) for website that lets you
| play around and understand these via demos. I'll see if I can
| find it.
|
| Edit: found it, it's
| https://www.audiocheck.net/audiotests_stereophonicsound.php
| cubefox wrote:
| I think for stereo sound, media like music, TV, movies and
| video games use loudness difference instead of time
| difference to indicate location.
| badmintonbaseba wrote:
| At least video games use way more complex models for that,
| AFAIK. It might be tricky to apply to mixes of recorded
| media, so loudness is commonly used there.
| miguelnegrao wrote:
| Unreal Engine, the only engine I'm more familiar with,
| implements VBAP which is just amplitude panning when
| played through loudspeakers for panning of 3D moving
| sources. It also allows Ambisonics recordings for ambient
| sound which is then decoded into 7.1.
|
| For headphone based spatialization (binaral synthesis)
| usually virtual Ambisonics fed into HRTF convolution is
| used, which is not amplitude based, specially height is
| encoded using spectral filtering.
|
| So loudspeakrs -> mostly amplitude based, headphones not
| amplitude based.
| badmintonbaseba wrote:
| Which makes sense, there is only so much you can do with
| loudspeakers to affect the perceived location, you don't
| really know where the loudspeakers and the listener are
| located relative to each other.
| miguelnegrao wrote:
| Actually, the farther way the speakers are from the
| angles specified in the 7.1 format (see
| https://www.dolby.com/about/support/guide/speaker-setup-
| guid...) worse will be the localization accuracy. And if
| the the person is not sitting centered relative to the
| loudspeakers, but closer to one of the loudspeakers
| localization can completely collapse, and it will sound
| like the sound only comes from the closest loudspeaker.
|
| In the case of gamers, they are usually centered relative
| to the loudspeakers, and usually the loudspeakers tend to
| be placed symmetrical to the computer screen, so the
| problem is not so bad.
|
| For cinema viewers sitting in the cinema the problem is
| much worse, most of the audience is off center... That is
| why 7.1 has a center loudspeakers, the dialogue is sent
| directly there to make sure that at least the dialogue
| comes the right direction.
| GenshoTikamura wrote:
| In music, simple panning works okay, but never exceeds the
| stereo base of a speaker arrangement. For truly immersive
| listener experience, audio engineers always employ timing
| differences and separate spectral treaments of stereo
| channels, HRTF being the cutting edge of that.
| miguelnegrao wrote:
| I believe Atmos as used in cinema rooms, is as far as I
| know amplitude based (VBAP probably), and it is
| impressive and immersive. Immersion depends more on the
| number and placement of loudspeakers. Some systems do use
| Ambisonics, which can encode time differences as well, at
| least from microphone recordings.
|
| HRTF as used in binaural synthesis is for headphones
| only, not relevant here.
| miguelnegrao wrote:
| Tihs is true, but a high density of loudspeakers allows the
| use of Wave Field Synthesis which recreates a full physical
| sound field, where all 3 cues can be used.
| badmintonbaseba wrote:
| The main utility isn't for the user to more precisely locate
| the sound source within the screen. Phased speaker arrays allow
| emitting sound in controlled directions, even multiple sound
| channels to different directions at the same time.
| miguelnegrao wrote:
| I'm sorry, but this is not accurate at all. Using "only" two
| signals, humans are quite good at localizing sound sources in
| some directions:
|
| Concerning absolute localization, in frontal position, peak
| accuracy is observed at 1/2 degrees for localization in the
| horizontal plane and 3/4 degrees for localization in the
| vertical plane (Makous and Middlebrooks, 1990; Grothe et al.,
| 2010; Tabry et al., 2013).
|
| from
| https://www.frontiersin.org/journals/psychology/articles/10....
|
| Humans are quite good at estimating distance too, inside rooms.
|
| Humans use 3 cues for localization, time differences, amplitude
| differences and spectral cues from outer ears, head, torso,
| etc. They also use slight head movements to disambiguate
| sources where the signal differences would be the same (front
| and back, for instance).
|
| I do agree that humans would not perceive the location
| difference between two pixels next to each other.
| GenshoTikamura wrote:
| Yep, the hearing is more akin to a hologram than a mere
| stereo pair imaging.
| K0balt wrote:
| You are misinformed.
|
| Amplitude, spectral, and timing are all integrated into a
| positional / distance probability mapping. Humans can estimate
| the vector of a sound by about 2 degrees horizontal and 4
| degrees vertical. Distance is also pretty accurate, especially
| in a room where direct and reflected sounds will arrive at
| different times, creating interference patterns.
|
| The brain processes audio in a way not too dissimilar from the
| way that medical imaging scanners can use a small number of
| sensors to develop a detailed 3d image.
|
| In a perfectly dark room, you can feel large objects by the
| void they make in the acoustic space of ambient noise and
| reflected sounds from your own body.
|
| Interestingly, the shape of the ear is such that different
| phase shifts occur for front and rear positions of reflected
| and conducted sounds, further improving localization.
|
| We often underestimate the information richness of the sonic
| sensome, as most live in a culture that deeply favors the
| visual environment, but some subcultures and also indigenous
| cultures have learned to more fully explore those sensory
| spaces.
|
| People of the extreme northern latitudes may spend a much
| larger percentage of their waking hours in darkness or
| overwhelming white environments and learn to rely more on sound
| to sense their surroundings.
| PaulHoule wrote:
| I learned to move around in dark rooms when I was young, I
| definitely can "feel large objects by the void they make" and
| people often turn on the lights because they thing I need
| them to "see" when I really don't.
| steelbrain wrote:
| This is a long shot but anyone know if there's an audio recording
| of the sound the display produced? Curious
|
| Edit: Found it:
| https://advanced.onlinelibrary.wiley.com/doi/10.1002/advs.20...
|
| Go to supporting information on that page and open up the mp4
| files
| IanCal wrote:
| Good find - the first video is a frequency sweep, video 2 has
| some music.
|
| Edit - I'm not sure that's the same thing? The release talks
| about pixel based sound, the linked paper is about sticking an
| array of piezoelectric speakers to the back of a display.
|
| edit 2- You're right, the press release is pretty poor at
| explaining this though. It is _not_ the pixels emitting the
| sound. It 's an array of something like 25 speakers _arranged
| like pixels_.
|
| https://www.eurekalert.org/news-releases/1084704
| jasonjmcghee wrote:
| This is the article that should be the main link- though
| still an incredibly misleading named technology.
|
| But the current one is just wrong.
| 1970-01-01 wrote:
| This technology literally sounds like a terrible idea. Why do I
| want to hear one drummer's drum over the others?
|
| https://advanced.onlinelibrary.wiley.com/action/downloadSupp...
| jtthe13 wrote:
| That's super impressive. I guess that would work for a
| notification speaker. But for full sound I have doubts about the
| low frequencies. I would assume you would need a woofer anyway in
| a home setting.
| timschmidt wrote:
| These are a thing: https://hackaday.com/2019/10/26/building-
| the-worlds-best-dml...
| SkyPuncher wrote:
| I have built those for an outdoor space. They work
| surprisingly well for mids to highs
| toast0 wrote:
| You could always have a separate speaker for low frequencies.
| Low frequency sound tends to be perceived with less of a
| directional component, so if you have nice directionality of
| the highs and a single source for the lows, that's pretty
| acceptable. Removing the need to handle highs might make it
| easier to put together a speaker for the lows in the confines
| of a modern flat screen.
| formerly_proven wrote:
| Many TFT and OLED panels today can produce sound unintentionally
| based on screen contents. This is mostly noticeable with
| repeating horizontal lines, which tend to produce whining at some
| fraction of the line frequency. Likely electrostiction.
|
| This here seems to be about adding separate piezoelectric
| actuators to the display though, it doesn't seem to use the panel
| itself.
|
| > by embedding ultra-thin piezoelectric exciters within the OLED
| display frame. These piezo exciters, arranged similarly to
| pixels, convert electrical signals into sound vibrations without
| occupying external space.
| amelius wrote:
| Can the video and audio be controlled independently?
| atoav wrote:
| Surely? Images play at <120Hz and sound requires you to run at
| or above the nyquist limit which for human hearing has the
| standard of 48kHz.
|
| So all AV systems run image and sound separately and thus you
| can affect them separately.
|
| (I assumed you assumed the changing colors displayed on the
| pixels with 120Hz somehow drive the sound which needs to change
| at 48000Hz)
|
| Anything but separate inputs makes no sense giving the
| magnitudes different frequencies at which it needs to be
| driven. Also, the color/brightness of a pixel does mean nothing
| for the sound.
| amelius wrote:
| I mean, can you play video without hearing e.g. a 120Hz hum?
| atoav wrote:
| Hopefully? I guess this depends on the decoupling. Or they
| just highpass it and leave that region to the sub.
| teekert wrote:
| I guess there are limits, like a pixel should never move more
| then its size, or you limit resolution (at least from some
| angels). So deep basses are out of the question?
|
| It is getting very interesting, sound, possibly haptics. We
| already had touch of course, including fingerprint (and visuals
| of course). We are more and more able to produce richt sensory
| experiences for panes of glass.
| milesvp wrote:
| Yeah, I don't know, I suspect you're right. I know that 25
| years ago there were big flat speakers thay drove sound with
| little holes. Those things could only handle high ends despite
| being very large themselves. But I know that with DSP you can
| treat an array of microphones as a single microphone, and the
| diameter of the array sort of dictates the size of the
| microphone. Speakers and mics tend to sort of be opposites, in
| that you can drive or be driven by either. For years I've
| wanted to build a wall of cheap speakers and experiment with
| this. I suspect I'd find out what we already know, which is to
| get deep frequencies you have to move a lot of air, and an
| array of small piezos can never move a lot of air...
|
| That said, it might matter a lot what the substrait was. If it
| was light and flexible, you could maybe get all the piezos to
| move it in a way to get a very deep frequency. You could
| probably get deeper frequncies than the power output of the
| piezos by taking advantage of the resonance frequency of the
| material. But you'd be stuck with that one frequency, and
| there'd be a tradeoff in response time
| ra120271 wrote:
| It would be interesting to learn in time what this means for the
| durability of the display. Do the vibrations induce stresses that
| increase component failure?
|
| Also how differing parts of the screen can generate different
| sound sources to create a sound scape tailored for the person in
| front of the screen (eg laptop user)?
|
| Interesting tech to watch!
| _joel wrote:
| I've got a Sony Bravia with similar technology for a few years
| now (it uses small actuators instead of generating from the
| oled itself, but the vibrations will be the same) and it's
| still sounding fantastic after daily use and a couple of moves.
| atoav wrote:
| So you are saying we get dieplays that could run wavefield
| synthesis?
|
| If you don't know what wavefield synthesis is: you basically have
| an array of evenly spaced speakers and for each virtual sound
| source you drive each individual speaker with a specially delayed
| signal that recreates the wavefield a sound source would create
| if it occupied that space. This is basically as close as you can
| get to the thing being in actual space.
|
| Of course the amount of delay lines and processing needed is
| exhorbitant and for a screen the limiting factor is the physical
| dimension of the thing, but if you can create high resulation 2D
| loudspeaker arrays that glow, you can also create ones that do
| not.
| kragen wrote:
| Because audio runs at such low sample rates, it's not
| exorbitant by current standards. Suppose you have an 8x16 array
| of speakers behind your screen, each running at 96ksps. That's
| only 12.3 million samples per second to generate, on the order
| of 200 million multiply-accumulates per second for even the
| most extreme scenarios. Lattice's iCE40UP5K FPGA
| https://www.farnell.com/datasheets/3215488.pdf#page=10 contains
| 8 "sysDSP" blocks which can do two 8-bit multiply-accumulates
| per clock cycle at 50MHz even when pipelining is disabled, so
| 800 million per second. It's 2.1 by 2.5 mm and costs US$5 at
| Digi-Key. I'm not familiar with AVX, but I believe your four-
| core 2GHz AVX512 CPU can do 256 8-bit multiply-accumulates per
| cycle, five hundred thousand million per second, so we're
| talking about an exorbitant amount of computation that's 0.04%
| of your CPU.
| chris_engel wrote:
| I wonder about the mentioned application in mobile devices. with
| mobile and tablet devices one usually has a very durable glass
| layer between the screen and the outside world - not sure if
| sound would ve able topass through that.
| kragen wrote:
| They just mounted the display on top of an array of piezo
| buzzers, is all. But it's true that that wouldn't work very well
| with an LCD.
| amelius wrote:
| How can this produce directional sound beams if there is a glass
| plate covering the display?
| pornel wrote:
| Probably similar to antennas -- using phase shifting and
| interference.
| amelius wrote:
| Yes, probably, but my question was more about the glass cover
| and if it wouldn't basically destroy the effect?
| spookie wrote:
| If it is touching the glass it amplifies it, if anything.
| (Edit: I should say it amplifies some frequencies while
| attenuating others)
| layer8 wrote:
| The talk about pixels is misleading. The research paper doesn't
| mention pixels. They attached a 3x3 array of piezoelectric
| elements (roughly 3 cm in diameter each) behind a 13" OLED panel
| (one picture also shows a 5x4 array), using a sturdy frame
| structure to minimize interference of acoustic vibrations between
| the 9 (or 20) elements of the array.
|
| Not to say that this isn't interesting, but it's not display
| pixels emitting sound.
| Animats wrote:
| Right.
|
| It's a way of putting speakers behind a display, which will
| probably be useful. This may improve bass response in laptops,
| because the speaker area is larger.
| charlie0 wrote:
| I would guess the bass is nonexistent here. Cool idea though.
| paulbgd wrote:
| Not this but similar, Sony's acoustic surface audio for their
| displays uses actuators behind the screen to vibrate it. it's
| not crazy bass but I'd say it's on par with regular built in
| tv/laptop speakers
| ComputerGuru wrote:
| Seems somewhat niche due to physics. When you are ten feet away
| from a screen (or even three), you can scarcely distinguish
| between audio emanating from the upper-left "pixel/voxel" (to
| give a new meaning to an old word) and from the bottom-right, let
| alone from two adjacent locations.
| russdill wrote:
| If you get enough, you might be able to do some really
| interesting things using it as a phased array
| deadbabe wrote:
| Not niche at all. You could have a phone for example that plays
| sounds from areas of the screen where they originate. Key
| presses, buttons, notification pop ups, etc.
| ComputerGuru wrote:
| You missed (or didn't address, at any rate) my point. For a
| phone where all audio channels are in between both ears (or
| even worse, held off to the right/left of both ears) with
| only a minute difference in the angle of the arc to each of
| the binaural inputs, convince me that you can reasonably
| distinguish between sounds emanating from different locations
| (facing the same direction - not at all like a speaker
| pointing out the side of each phone!!) at a rate
| statistically distinguishable from chance.
| saltcured wrote:
| I think you're trying to make an argument similar to those
| arguing against "retina" displays, i.e. there is some minimum
| perceptual angular resolution for sound, so information finer
| than that is pointless? I think you're either underestimating
| the perceptual resolution or assuming a very small screen at a
| large distance.
|
| I think that kind of resolution is good enough to overlap a lot
| of task focused screen fields of view. I have experienced a
| pretty clear "central" sound stage within 30-45 degrees or so
| with regular stereo speakers. That field can imply a lot of
| subtle positioning within it, not even considering wild panning
| mixes. I'm talking about the kind of realistic recording where
| it feels like a band in front of you with different instruments
| near each other but not colocated, like an acoustic ensemble.
| Obviously you cannot shrink this down to a phone at arm's
| length or a small embedded control screen and still have the
| same amount of spatial resolution crammed into a very narrow
| field.
|
| When I sit with a 14" laptop at a normal distance for typing,
| it is also easy to distinguish tapping sounds along the screen.
| I just did a blind test by closing my eyes and having my wife
| tap the screen with a plastic pen. The interesting question to
| me, though, is whether that is just perception via the binaural
| sense, or really incorporating some intuition about the
| screen's structure. It's response to a tap does clearly vary by
| distance from bezels and hinges...
| ComputerGuru wrote:
| Impressed that you took the time to run a quick test. Spatial
| compression is a hard problem though, the most expensive
| sound bars are easily beat by a cheap 2.1 setup. Phones are
| (mostly) still mono output even though a speaker out the top
| and bottom (perpendicular to the viewing angle) would be a
| win for watching videos in landscape, probably because the
| improvement wouldn't be noticeably appreciated (enough to be
| economically feasible, anyway).
|
| Interesting research all the same, of course!
| Xss3 wrote:
| Can this be used like a phased array?
___________________________________________________________________
(page generated 2025-05-29 23:01 UTC)