Canon developed the first ultra-high-sensitivity interchangeable-lens camera equipped. It uses a Type 1 Single Photon Avalanche Diode (SPAD) image sensor. While you may not see this in your next mirrorless camera, the low-light visibility can see subjects from kilometres away.
The Canon MS-500 is unique not in the technologies that make up the sensor, but in how it combines existing technologies. It's an evolution, not a revolution. The 3.2-megapixel SPAD sensor delivers very good performance as can be seen in the image above.
It uses industry-standard B4 bayonet lens mount based on BTA S-1005B standards. It's a common mount for 2/3-inch broadcast lenses that allows users to use the new camera with Canon’s large line of broadcast lenses, so not engineered for security cameras.
In areas with extremely high-security levels, such as seaports, public infrastructure facilities, and national borders, high-precision monitoring systems are required to surveil targets both day and night accurately. The new MS-500 camera is the world’s first ultra-high-sensitivity camera equipped with a SPAD sensor, achieving a minimum subject illumination of 0.001 lux”Canon USA
Thanks to temporal resolution and high sensitivity, there are expectations that this technology may be used in the process of obtaining high-speed, high-precision 3D special information for such applications as distance measurement for automated vehicles, Augmented Reality (AR), Virtual Reality (VR) and Mixed Reality (MR).Canon USA
Unlike traditional CMOS image sensors, like those found in Canon’s DSLR and mirrorless ILC models, a SPAD sensor measures each light particle (photon) reaching every pixel on the image sensor. In contrast, CMOS image sensors measure the amount of light that reaches a pixel within a given time.
CMOS sensors read light as electric signals by measuring the volume of light that accumulates in a pixel within a certain time frame, which makes it possible for noise to enter the pixel along with the light particles (photons), hence contaminating the information received,” Canon explains.
Meanwhile, SPAD sensors digitally count individual photon particles, making it hard for electronic noise to enter. This makes it possible to obtain a clear image,” Canon says. Each photon that enters a pixel on a SPAD sensor is immediately converted into an electric charge. The resulting electrons eventually multiply, like an avalanche, until they form an immense enough signal charge to be extracted.Canon USA
SPAD sensors are unique and well suited for shooting in low light environments. SPAD sensors can count each photon entering a pixel. It is then amplified a million times and output as an electrical signal. It is this capability that enables close to zero noise during signal readout. Current full frame or APS-C CMOS sensors are not capable of this.