New Image Sensor SPAD Can See In The Dark

The Japanese camera specialist Canon has developed a new image sensor that is said to be able to “see in the dark”. Due to a greatly increased light sensitivity, the sensor chip should deliver usable images even in almost complete darkness.

As reported by the Japanese business service Nikkei Asia, Canon, together with some other Japanese companies such as Panasonic and Sony, wants to use a technology called “Single-Photon Avalanche Diode” (SPAD) to ensure that the new sensor “sees” significantly more than normal CMOS based camera sensors.

The system “amplifies” a single photon reaching the sensor into a large number of electrons so that objects can still be made visible even in an almost completely dark environment. It is primarily intended to be used in security cameras and sensors for autonomous vehicles.

Used Along With LIDAR Sensors

In the case of CMOS-based cameras, on the other hand, the signals are generated based on the photons that strike in a certain period of time. Canon’s SPAD sensor has a resolution of 3.2 sensor pixels and thus offers three times the resolution than Canon’s image sensors usually used in security cameras. The sensor can determine the time between the emission and the return of the light emitted by the camera in the range of less than a nanosecond so that the object detection should be more precise.

With the previously used infrared-based night vision cameras, mostly only black and white images are generated, while normal, highly sensitive cameras are now able to deliver useful images in moonlight thanks to software support and large sensors. At the same time, however, the image noise increases sharply with decreasing brightness.

With Canon’s SPAD sensors one wants to detect objects with the help of measurement between the emission and the return of the light after reflection by the respective object. The SPAD technology is thus able to capture the space in three-dimensional form and is to be used in LIDAR sensors, among other things.

In addition to Canon, Panasonic and Sony have also developed SPAD sensors, with the two Japanese companies still working on increasing the number of pixels on their sensors or on preparing for mass production. Sony plans to deliver SPAD sensors for LIDAR systems as early as March 2022, while Canon for its part intends to introduce the first security cameras equipped with them by the end of 2022.