Emerging Technologies of Optical Microphones
Since ancient times, humans have sought acoustic amplification for different purposes. For example, thousands of years ago, in Ancient Greece, actors wore special masks that amplified the sound of their voices in the theater, which already had architectural features that allowed the sound to reach the last rows of the audience. The Maya people in Southern Mexico played a lot with acoustics in their constructions, as in the temple of Kukulcan, and there are many examples like these. We have invented metal speakers for turntables, and dynamic microphones and condensers, always in the face of the challenges brought by the advancement of technology. Now, in our times of smartphones, Wi-Fi, 5G technology, and so on, it is a necessity to have a new type of microphone that manages to capture sound without interference of any kind.
Welcome to the era of optical microphones!
But what exactly is an optical mic? Well, it is not rocket science: people are simply using already existing ideas and mixing them up — however, it’s a tremendous improvement still. An optical microphone is a visual monitor, a camera, that captures the impact of sound waves on a receiver and thus transforms all that data into sound. Sound is essentially movement, vibrations hitting a surface after traveling through the air. So, it is possible to capture sound as we have been doing it for almost 150 years by turning sound waves into electromagnetic energy and now it’s possible to capture it thanks to the way it looks (so to speak…) It’s a tremendous paradigm shift, indeed, simply derived from implementing some basic concepts from classic physics that we already knew.
Let’s remember that trends in technology do not follow a linear or progressive pattern. The evolution of history, like technological (and other) trends, is rather cyclical. In reality, scientists never invent anything, they just move existing things out of place. That’s the way we create. That’s how we humans have advanced throughout the history of science. A trend is, first and foremost, a social inclination towards a topic, behavior, or product, the use of which usually generalizes in the community until it creates a pattern. What is key is never forgetting that it never comes out of nowhere. We already knew what the sound vibrations on liquid or sandy surfaces look like; the next step is to go backward: from the result of such waves on a surface, to compose the sound that produced that very outcome by tracing it visually.
In a nutshell, that’s the job of an optical microphone.
In the 1880s, Alexander Graham Bell was inventing the telephone and we know that he first thought of an optical transducer to carry the sound from the sender’s voice to the receiver’s (this paper explains it all very well.) Bell knew that light could be the ideal medium to transmit a sound signal. He called this idea The Photophone Transmitter. Of course, the challenge was huge at that time. Fiber optics had not been invented, and, in fact, putting this idea into practice meant that Graham Bell gave up his attempt to convert sound into light and vice versa. This idea was taken up again in the 1920s, due to advances in quantum physics, and gradually matured to the point where Phone-or, an Israeli company in conjunction with Sennheiser, developed the first optical microphone in the 1990s, and the rest is history.
Now, the most notorious feature is that this type of microphone allows isolating the sound waves that converge in a space so that they can be heard individually. This is quite useful, not only so that the interference of cell phones does not affect communication (and, among other things, the stewardess does not force you to turn off your phone on the plane,) but to emit sounds more accurately. This is not only valuable for a recording studio or a concert with a lot of noise around, but for, for example, scientific studies on volcanoes, animals, or celestial bodies, or for police and military operations, or even to study the human body and monitor our health. The second great feature of this type of microphone is the small size and simplified composition of its parts. This translates into lower costs, practicality, and accuracy.
The obligatory question relates to how optical microphones will revolutionize mankind, and, in particular, the sound industry. When it comes to recording music in a studio, needless to say, it’s more than convenient — it’s necessary for this day and age. Not to speak about film productions (just think of the challenges of recording dialogue from a moving airplane…) All trends produce their own disruptions, overcome one set of challenges, but, in turn, produce others. Therefore, let’s wait, watch, and learn.
If you need advice for your audiovisual production, do not hesitate to contact Enhanced Media Sound Studio: a team of experts who are aware of avant-garde trends such as those presented in this post.
