Our Technology

The highest image quality at the lowest practical X-ray dose is the challenge for every X-ray detector, in every use case. As a compound semiconductor, single-crystal perovskite has a set of attributes designed to outperform existing photon-counting and scintillator-based detectors. Its solution-based growth is quicker and more cost-effective to scale than conventional X-ray semiconductor manufacturing, which improves supply-chain resilience and will allow for more widespread adoption.

Perovskite absorbs X-rays efficiently and converts them directly into electrical charge, without the intermediate conversion to light that scintillator (EID) detectors rely on. This direct conversion, combined with efficient charge transport and high sensitivity, supports high resolution multispectral imaging.

PRISM-X is designed to deliver clearer, faster and more informative images at lower X-ray doses, uncovering subtle contrast and fine detail that conventional detectors can miss. Its low-temperature, scalable manufacturing opens the way to cost-effective photon-counting CT imaging systems in industrial inspection, security baggage scanning, and healthcare diagnostics.

Perovskite

Perovskite is a term that describes a broad family of semiconductor crystals built from repeatable, cuboidal structures that are structurally similar to calcium titanate (CaTiO3 in the form ABX3). Calcium titinate crystals were discovered by Gustav Rose (left image) in the Ural mountains in 1839, these crystals were named after Lev Perovski (right image), a Russian nobleman and mineralogist. The structure of perovskite was first described by Victor Goldschmidt, a Swiss-born, Norwegian geochemist in 1926, who is considered to be the founder of modern inorganic crystal chemistry.

More recently, Prof. Sam Stranks (University of Cambridge and Co-founder & CSO, Clarity Sensors) has played a pioneering role in the development and understanding of halide perovskite semiconductors, which are used in solar cells, LEDs, and X-ray detectors. His research has developed some of the key perovskite materials, uncovered how charge carriers behave and recombine in perovskites, identified sources of efficiency losses, and revealed how these materials degrade over time. Using advanced material characterisation techniques like optical spectroscopy and nanoscale microscopy, Stranks’ work has guided the design of longer-lasting, high-performance perovskite devices such as X-ray detectors and solar cells.

Image credit (left image): Rudolph Hoffmann, Public domain, via Wikimedia Commons

Image credit (right image): Friedrich Jentzen, Public domain, via Wikimedia Commons

Perovskite Precision

Perovskites can be easily engineered to have particular properties suited to different applications such as solar, X-ray & photo detection and LEDs. In the future, they promise wider advances in quantum, photonics and lasing. As the world’s first high purity, single-crystal perovskite foundry we are ideally positioned to exploit these exciting advances.

In detectors, the metallic element at the centre of our perovskite crystal has a high atomic number, which lets it capture X-ray photons as they pass through the sample and into the detector crystal. Each interaction produces a small cloud of electrical charge that can be read as a signal. As we develop PRISM-X, we will integrate our perovskite crystals onto readout chips (ASICs) that collect these charge signals. The signals are processed into highly detailed images for medical diagnosis, threat detection, product defect detection and many other uses.

Photon Counting

Existing CT scanner detector technology converts the incident photons into light using a technique called scintillation. The photon travels through the tissue/material/sample and enters a scintillator crystal in the detector causing it to release flashes of visible light. The number of light photons released is proportional to the energy of the incident X-ray. The light photons are converted to an electrical signal using a photodiode which is attached to the scintillator crystal. The signals are sent to a computer to be reconstructed into a digital image of the tissue/material/sample.

Photon-counting detectors are semiconductor crystals and are much more efficient as they directly convert the incident X-ray photons into electrical charges. The charges are separated by biasing the pixelated crystal with a cathode on the top of the crystal and an anode on the bottom. The pixels count the number of photons entering and register their individual energy level. This additional data, when converted into a digital image, makes photon-counting images much clearer. Noise levels in photon-counting detectors are extremely low (they are often called ‘noiseless images’) which additionally improves image resolution. The energy level information captured means that images always have spectral information i.e. they can be coloured. With a very low noise level every photon can be counted meaning that images are intrinsically higher in resolution compared to existing detectors which miss lower energy photons as they are lost in the noise.