1mm thick piezo film speaker from Kyocera used in LG's curved-screen OLED TV

1mm thick piezo film speaker from Kyocera used in LG's curved-screen OLED TV


Kyocera has announced the commercialization of an ultra-thin, lightweight piezo film speaker, called "Smart Sonic Sound".

The speaker is being produced in three sizes: small, medium and large. The medium size speaker weighs 7g and is 1mm thick, yet can create the same audio volume as a conventional electromagnetic speaker.

"In the middle, you can see a white ceramic part called a piezo element, which vibrates when electricity is applied. When the audio signal comes in, it creates a wave, which is transmitted to the film. That makes the film resonate, so you get a loud sound. The film can't be too soft or hard, so getting the balance right requires technical know-how."

This speaker is being used in the new 55" curved-screen OLED TV from LG. This is the first time in the world piezo actuator audio technology has been used in a flat-screen TV.

"Speakers used in TVs usually face downwards or backwards, because TVs are now so slim, and consequently, high tones sound muffled. A feature of our speaker is that, because the film vibrates, the sound travels widely. In particular, for high and mid-range tones, sound is transmitted through virtually 180 degrees."

"The timing of LG's new product and our speaker concept were well-matched, so we've been able to commercialize this relatively quickly. To design this for curved OLED TVs, we made the frame and film transparent, and fine-tuned the design to get the same great sound. That's why LG utilized this."

Additionally, as the speaker is small and light, yet can project sound waves almost equally across a 180° radius, Kyocera plans to extend it's range of applications to include mobile devices and car audio systems.

"Cars usually have 4 or 6 speakers, each weighing 1 kg. But this speaker weighs 100 g at most, so it can make car audio systems much lighter. That gives you the benefit of better mileage. Another feature of this speaker is, it doesn't use neodymium. So, it could be a way to handle resource risks as well."

"By this time next year we plan to be producing around one million devices, and we think it will become a 10 billion yen (~US$100 million) business in about five years time."

Source:  Kyocera, LG Electronics