The stacked sensor design that brought a speedy 16 fps to Sony’s high-end compacts could be headed to smartphones. On Tuesday, Sony announced a three-layer sensor for smartphones, the first time a DRAM layer has been added in sensors designed for smartphones.
Like the RX100 IV and RX10 II, the latest smartphone sensor from Sony uses three layers. The typical two-layer sensor design uses a layer of pixels and a layer of circuits to process that data, but the new design includes a third layer of DRAM or temporary storage for all that information.
By storing data temporarily on the sensor itself, the camera can process those files faster — Sony says the new design is four times faster than the average smartphone sensor. That will allow the sensor to shoot at speeds up to 1,000 fps in full HD for taking slow motion videos to the extreme. Or, the sensor can handle 19.3-megapixel stills at 30 fps.
But along with creating cool slow-mo effects, the sensor will help solve a common issue when using smartphone cameras to shoot action. Smartphone cameras don’t have a physical shutter — instead, the sensor is exposed all the time and an electrical surge tells the camera when to record a picture. Because of that electronic design, the image is exposed one row of pixels at a time.
On a typical smartphone camera, while processing each row of pixels is fairly quick, it’s not fast enough to eliminate distortion with fast objects. Since the new sensor can process those rows of pixels four times faster, that distortion, called a rolling shutter, is reduced.
Sony began using sensors with a third DRAM layer in 2015 with the introduction of the RX100 IV and RX10 II, enabling faster video frame rates as well as speedier stills. While the new smartphone sensor has the same three layers, it is a smaller 1/2.3-inch size — once common in point-and-shoot cameras and now used in many smartphones, compared to the 1-inch option found in Sony’s advanced compacts.
Sony manufactures camera sensors used by several different brands. While Tuesday’s announcement is only a sensor, the faster performance and reduction of the rolling shutter distortion could be integrated into multiple smartphones models in the future.