Photon-number-resolving megapixel image sensor at room temperature without avalanche gain

Abstract

In several emerging fields of study such as encryption in optical communications, determination of the number of photons in an optical pulse is of great importance. Typically, such photon-number-resolving sensors require operation at very low temperature (e.g., 4 K for superconducting-based detectors) and are limited to low pixel count (e.g., hundreds). In this paper, a CMOS-based photon-counting image sensor is presented with photon-number-resolving capability that operates at room temperature with resolution of 1 megapixel. Termed a quanta image sensor, the device is implemented in a commercial stacked (3D) backside-illuminated CMOS image sensor process. Without the use of avalanche multiplication, the 1.1 μm pixel-pitch device achieves 0.21e− rms average read noise with average dark count rate per pixel less than 0.2e− ∕s, and 1040 fps readout rate. This novel platform technology fits the needs of high-speed, high-resolution, and accurate photon-counting imaging for scientific, space, security, and low-light imaging as well as a broader range of other applications.

Megapixel time-gated SPAD image sensor for 2D and 3D imaging applications

“…The QIS inherits several advantages of CMOS image sensors such as a potentially small pixel size, high spatial resolution, low dark current, high quantum efficiency and low power consumption. A spatial resolution of up to 1 megapixel with 1.1µm pixels has been reported in a QIS [18,19], enabling low noise and high dynamic range imaging for scientific, space, and security applications. A limitation of the QIS technology, though, is timing resolution.…”

Imaging with quantum states of light

“…We have seen in this section three main types of camera technologies that can be used to perform quantum imaging, in Table 1 we have reported some of the most important characteristics of such cameras in the context of quantum imaging. It is useful to note that new technologies such as SPAD arrays [79,80,81,82], matrices of superconducting nanowires single photon detectors [83,84], or new back-side-illumination CMOS technologies [85] are able to resolve the number of photons and are very promising alternatives to the cameras presented here. However, these technologies are not yet sufficiently mature to be implemented in quantum imaging applications involving correlated photons.…”

Asynchronous Single-Photon 3D Imaging

“…Implications and future outlook: Due to their compatibility with mainstream CMOS sensor fabrication lines, the capabilities of SPAD cameras continue to grow rapidly [11,32,12,20,18,1,3]. As a result, the proposed methods, aided by rapid ongoing advances in SPAD technology, will potentially spur wide-spread adoption of single-photon sensors as all-purpose cameras in demanding computer vision and robotics applications, where the ability to perform reliably in both photon-starved and photon-flooded scenarios is critical to success.…”