Austrian startup Xarion Laser Acoustics GmbH is bringing a new membrane-free optical microphone into the market. Instead of replying on the old fashion vibrating diaphragm technology, Xarion’s technology utilizes laser to hear sound.
How does it work? IR beam with 1550nm is shining through a Fabry-Perot etalon and a detector on the other side to capture the transmitted beam. Sound pressure changes in the etalons refractive index and will alter the optical wavelength thus in the end converts into electrical signals.
Can detect refractive index changes as small as 10-14(1microPa)
Frequency range: infrasound 5Hz to ultrasound in the megahertz range
Only few square millimeters in size
Resistant to vibration, wind or external influences
MEMS microphone market in 2016 worth around $1.04 billion and estimated around $1.62 billion in 2020, according to SAR Insight & Consulting.
Source: http://www.laser-community.com/en/xarion-laser-microphone; www.xarion.com