In a world where "larger" pixels and "deeper" pixels dominate the discussion about smartphone sensors, Samsung has decided … to take a different path. The image sensor giant has unveiled the world's first 0.7 μm pixel mobile image sensor, which has been able to pack 43.7 megapixels into a sensor with a width of less than 5 mm.
The Samsung ISOCELL Slim GH1
To combine this tiny size with a resolution that meets the 2019 specifications, Samsung used the Tetracell Technology that allows the Slim GH1 to combine two sensors in one sensor Using a Quad Bayer filter to group four-pixel squares.
In good light, a remosaicing algorithm allows this image sensor to capture full 43.7 megapixel images. When the light drops and these tiny 0.7 μm pixels cause serious noise problems, the 4-layer design allows the sensor to produce better 10.9 megapixel images with "higher photosensitivity than a 1.4 μm pixel Image sensor corresponds to "generate. The best from both worlds.
And since this downsized Tetracell resolution is still sufficient to cover 4K, the ISOCELL Slim GH1 promises "more detailed backgrounds when recording high-definition video or selfies at 60T frames per second (fps)." 
This is another impressive achievement for Samsung, which has made some important advances in smartphone image sensor technology with its ultra-high-resolution 64MP and 108MP ISOCELL Bright image sensors using the same Tetracell technology. For the ISOCELL Slim, Samsung simply reversed the script and packed more resolution and performance onto a smaller chip with the same technology.
The hope is that this sensor will allow for "sleeker, streamlined designs, as well as outstanding image experiences on tomorrow's smartphones".
Oh, and if you're wondering if this technology will soon make it "real". For cameras, the answer seems to be yes: Sony has already developed a Quad Bayer full-screen version of the 61MP for the Sony a7R IV, which offers the same approach to "the best of both worlds" for much larger, more powerful cameras.