Diffuse correlation spectroscopy (DCS) is a well-established method that measures rapid changes in scattered coherent light to identify blood flow and functional dynamics within a tissue. While its sensitivity to minute scatterer displacements leads to a number of unique advantages, conventional DCS systems become photon-limited when attempting to probe deep into the tissue, which leads to long measurement windows (∽1 sec). Here, we present a high-sensitivity DCS system with 1024 parallel detection channels integrated within a single-photon avalanche diode array and demonstrate the ability to detect mm-scale perturbations up to 1 cm deep within a tissue-like phantom at up to a 33 Hz sampling rate. We also show that this highly parallelized strategy can measure the human pulse at high fidelity and detect behaviorally induced physiological variations from above the human prefrontal cortex. By greatly improving the detection sensitivity and speed, highly parallelized DCS opens up new experiments for high-speed biological signal measurement.

中文翻译：

---

快速和灵敏的扩散相关光谱，具有高度平行的单光子检测

漫射相关光谱法（DCS）是一种行之有效的方法，可测量散射相干光的快速变化以识别组织中的血流和功能动力学。传统的DCS系统对微小散射体位移的敏感度带来许多独特的优势，而当尝试深入探查组织时，其光子受到限制，从而导致较长的测量窗口（∽1秒）。在这里，我们介绍了一个高灵敏度DCS系统，该系统具有集成在单光子雪崩二极管阵列中的1024个并行检测通道，并展示了能够在高达33的组织状体模中检测到1厘米深的毫米级摄动的能力Hz采样率。我们还表明，这种高度并行化的策略可以高保真度地测量人类脉搏，并从人类前额叶皮层上方检测行为诱发的生理变异。通过大大提高检测灵敏度和速度，高度并行化的DCS开辟了用于高速生物信号测量的新实验。