A regular camera captures the world as a series of frames: twenty-four, sixty, or even a hundred images per second. That's enough for filming a falling drop, but inside a living cell, events unfold a thousand times faster. Protein molecules carry cargo, membranes bubble, ions slip through channels — all in fractions of a millisecond. To catch such moments, you need a sensor that doesn't pause between frames but registers every change in brightness the moment it happens. Such sensors are called event-based: they don't record a full picture but report 'it got brighter here' or 'it got darker here' at the instant of the event.
But event-based sensors have a weakness: they hardly distinguish colors. For a microscope, that's a serious drawback, because in biology the color of a glow is a molecule's signature. One protein glows green, another red, and the hue tells you who's who. The authors of the new work combined an event-based sensor with a regular camera, in front of which sits a diffraction grating — a plate that splits light into a rainbow, like a water droplet in the sun. The regular camera slowly but accurately determines color, while the event-based sensor quickly but colorlessly captures motion. A computer merges both data streams and produces an image where each flash is tinted with its own hue.
The new microscope already distinguishes molecules whose emission peaks are just 23 nanometers apart — hundreds of times narrower than the visible spectrum. Previously, this would have required swapping optical filters or scanning the sample point by point, wasting time. Now you can track the motion of several types of molecules at once and see their colors without interrupting the observation. This paves the way for studying fast processes in living cells: how viruses enter, how neurons exchange signals, how a drug reaches its target.
A camera that doesn't sleep between frames but sees every change in light is like an eardrum: it senses not individual beats but a continuous stream of vibrations. The new microscope is just as sensitive to light, but it also distinguishes colors, like an ear distinguishing pitch. Combining two senses in one instrument is the key step forward.
Event-based sensors were originally built for robots and tracking systems: they don't waste energy recording a static background, only reacting to changes. This allows capturing fast motion without blur.
In the series 'Altered Carbon,' future cameras capture memories and emotions in minute detail — the new microscope takes a first step toward filming living processes without losing color or motion.