LCD Screens Double as Speakers

An anonymous reader writes "The BBC has a story about a company who has developed an LCD screen that can produce sound as well. They claim that the sound quality is quite good, and compare it to average multimedia computer speakers. Also NEC is making and selling computers that use this technology in Japan. Hardware integration like this should make for some interesting appliances in the next few decades."

Re:light music?

[ceejayoz]

It's just an acrylic panel over the front of the display, so it shouldn't affect the lifespan of the LCD at all.

Not New Tech...

[FosterSJC]

First, obviously, the sound isn't coming from the light or the screen or whatever. There is a thin acrylic sheet that is used as a sounding board:

The technology works by placing a thin acrylic panel over the computer display. This is attached at the edges to a couple of exciters.

These moving coil motors make the acrylic screen vibrate to produce the sound.

This is the same tech, essentially, that drives those flat-panel computer speakers, and the Soundbug [thinkgeek.com] over at thinkgeek.

Re:Image integrity?

[Musashi Miyamoto]

It sounds like these speakers are similar to Martin Logan electrostatic speakers, and the screen will not produce anything close to low-frequency sound. The screen will likely require a midrange/woofer to reproduce the full spectrum of sound.

Electrostat speakers are typically transparent like glass, but held between two screens to allow the sound to travel. The article says the company claims the monitor has a "universal sweet spot", but that is probably corporate marketing talk for "no sweet spot". Most panel based electrostat speakers have a very very tiny sweet spot, and you need to be sitting perfectly between the two speakers.

From howstuff works:

These speakers vibrate air with a large, thin, conductive diaphragm panel. This diaphragm panel is suspended between two stationary conductive panels that are charged with electrical current from a wall outlet. These panels create an electrical field with a positive end and a negative end. The audio signal runs a current through the suspended panel, rapidly switching between a positive charge and a negative charge. When the charge is positive, the panel is drawn toward the negative end of the field, and when the charge is negative, it moves toward the positive end in the field.

Re:i don't know what's happening

[joelhayhurst]

For those of you too lazy to search Google for "Japanese invisibility cloak", here is the link that started it [ananova.com] and the project home page [u-tokyo.ac.jp] (with movies).

The objects are NOT truly transparent. They just appear that way due to optical tricks. Basically, they project what is behind an object to what is on the front of it using cameras, projectors, and mirrors. It's a neat idea, and he suggests some useful applications, but nothing like most were expecting upon seeing the pictures. Still, makes for some kick-ass videos.

WTF are you talking about?

[pr0ntab]

How did this get modded Interesting?

If you go to the FAQ on NXT's website [nxtsound.com], you'll discover they use superposition principles to produce virtual channels in the sweet spot. They can do two; supposedly three (L, R + center) is possible.

Watermark, joint-stereo, give me a fucking break. Add nonsense buzzwords to a post and get modded up! A 2-step plan for slashdot success. (Unless you meant to be funny... in which case a big YOU ARE TEH 1Di07s!!! to the mods active today)

Re:Image integrity?

[nattt]

These speakers are nothing like the electrostatics you mention. They work on a completely different principle - the distributed mode loudspeaker. They use exciters (moving coil units) to drive a panel into breakup mode (chaotic) where it produces sound. You can turn lots of types of materials into speakers this way - the trick being where you place the exciters and the exact specs of the material. The sound produced is an area source rather than a line or point source of conventional (or some electrostatic) speakers, which means it interacts with the room, and yes, it doesn't produce much bass. Electrostatics however, if large enough can not only produce bass, but very high quality bass too. Martin Logan's often use a bass driver but that's so that they can make the panels smaller and cheaper. A full range electrostatic like a QUAD, is a wonderful speaker to hear as it produces very little distortion compared to a conventional cone speaker.