A New Camera Sees Invisible Particles in 3D — One Block Replaces Millions of Detectors

Subatomic particles are notoriously difficult to photograph. When a particle passes through a detector, it leaves a faint trail of light, but reading that trail in three dimensions usually requires stacking millions of tiny, precise components — photodiodes, fibers and electronics that add up to a machine the size of a room. A team at ETH Zurich has now shown a much simpler idea works: one solid block of light-producing material, paired with a special camera and an AI decoder.

The new device, called PLATON, uses a single block of scintillator material. When an invisible particle such as a neutrino or a high-energy cosmic ray crosses through the block, it generates a brief flash of light at the point of impact. An ordinary camera can only measure how much light arrives; a light-field camera also records where that light is coming from. By placing a micro-lens array between the main lens and the sensor, PLATON captures both the intensity and the direction of the glow.

Because each tiny lens samples light from a slightly different angle, the system can recover depth. Machine-learning algorithms then stitch the many flashes into a three-dimensional reconstruction of the particle trail, in much the way a photographer might recover focus after the fact. The approach collapses a detector that once needed millions of individual sensors into something closer to a single imager.

The payoff is twofold. First, particle physics experiments could become far cheaper and easier to scale — a bigger detector is no longer a logistics nightmare. Second, the same principle could improve medical imaging: PET scanners already rely on detecting particles, and a PLATON-style design could sharpen their pictures and reduce their cost.

Knowledge takeaway: the PLATON detector replaces millions of discrete sensors with one scintillator block; a light-field camera and micro-lens array record the direction of the light each particle flash produces; AI then reconstructs the trail in 3D, opening cheaper, scalable particle physics and sharper, cheaper medical imaging.