On May 19, the presentation of the revolutionary ISOCELL photo sensor took place, but the details of its work were kept secret until recently. And only the other day, a South Korean company finally decided to share its secrets with the public.
The 50 megapixel ISOCELL GN1 sensor uses two advanced technologies at once: Dual Pixel and Tetracell. The first one is based on the use of 100 million phase detectors and two LEDs that make up the pixel. During focusing, each of the photodiodes creates its own image, then they are checked and the algorithm is repeated until a decision is made on the identity of the images, as well as on the detection of focus. And the speed of the algorithm is much higher than that of conventional focus analysis systems.
The second technology is related to the placement of color filters. Standard practice of using RGB-sensors is based on the placement of multi-color filters in a chess order. In ISOCELL GN1, similar color filters are placed four at a time, which gives a brighter image in low light conditions. When the illumination level of the subject is high, the color filters are rearranged into a mosaic, increasing the resolution of the image.
Today, the sensor is used in only one smartphone, the vivo X50 Pro PLUS.