Light Instead of Microphones: A New Way to See Inside the Body
A laser hits tissue, and the tissue responds with a barely audible click — a sound wave. Sensors pick it up, and from that, an image of what's inside is built. That's how photoacoustic imaging works: light reaches deep, and sound carries the picture out.
In the new scheme, there are no sensors. Instead, several thin light beams are sent through the area where the wave has passed.