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Singular Photonics, a pioneer in computational imaging technology, is transforming the capabilities of photon detection by embedding advanced processing directly within its SPAD (Single-Photon Avalanche Diode) sensor arrays. Unlike conventional sensors that transmit raw photon data to external systems, Singular’s approach uses a 3D-stacked architecture that places high-density digital logic directly beneath each SPAD pixel. This unique integration allows the sensor to perform complex operations, such as histogramming, time-binning, and autocorrelation - at the pixel level, enabling real-time analysis of photon events as they are captured.

Each SPAD detector in Singular’s arrays operates in avalanche mode, instantly converting a single photon into a digital pulse with timing resolution measured in tens of picoseconds. Because the signal is inherently digital, it avoids the noise and complexity of analog amplification and analog-to-digital conversion. This digital precision makes the sensors exceptionally well-suited for low-light environments and high-speed measurements. However, the true innovation lies in the computational layer: the embedded logic beneath each pixel can execute millions of operations per second in parallel, turning each photon into meaningful, application-ready information without requiring off-chip processing.

This design philosophy - bringing computation to the point of detection - enables applications that go far beyond traditional imaging. The sensors are capable of extracting temporal, spectral, and statistical insights in real time, which is particularly valuable in fields like biomedical imaging, spectroscopy, and depth sensing. In diffuse correlation spectroscopy, for example, the company’s Andarta sensor, a 512 x 512 SPAD array, performs ensemble autocorrelation directly on-chip with lag times below one microsecond per macropixel. It uses around 120 million transistors to deliver over half a trillion multiply-accumulate operations per second, all while operating at a power budget of just 0.3 watts. This allows for continuous, real-time monitoring of physiological signals such as cerebral blood flow, without streaming raw data to an external processor.

The Sirona line sensor, another key innovation, focuses on time-resolved spectroscopy. By embedding time-binning and histogramming directly into the sensor array, it supports advanced techniques like fluorescence lifetime imaging (FLIM) and Raman spectroscopy with reduced latency and improved efficiency. Demonstrations of Sirona have achieved full-spectral FLIM imaging at 0.2 frames per second in full resolution, with potential for real-time performance at 10 frames per second using resolution and binning trade-offs. These capabilities, delivered through compact and power-efficient designs, underscore the broader promise of Singular’s sensor platform: to deliver advanced optical sensing in form factors suitable for portable, embedded, or wearable systems.

Singular Photonics’ sensors embody a fundamental shift in imaging technology by combining precise photon detection with embedded, high-throughput digital computation. This integrated architecture not only improves speed and energy efficiency but also enables a richer, more nuanced understanding of light signals, paving the way for a new generation of intelligent, light-aware devices.

Click here to read about Diffuse Correlation Spectroscopy with the Andarta Sensor.