Smartphones quickly became the best compact cameras ever, but they could soon take another leap forward thanks to an innovative new Sony image sensor.
Sony’s semiconductor division just announced that it has manufactured the world’s first stacked CMOS sensor with dual-layer transistor pixels. Today’s CMOS sensors have both their photodiodes and pixel transistors on the same substrate (or layer), but Sony’s new chip separates them on two distinct levels.
What does this mean for the image quality? Sony claims that this new architecture doubles the saturation signal level of each pixel, effectively exposing them to twice as much light. This should significantly improve the dynamic range of the sensor, while freeing up enough room for larger amp transistors to reduce nighttime noise.
The benefits should be especially evident in high-contrast scenes, like those with bright sun and dark shadows, which previous smartphones struggled with. Phones today use intelligent multi-image processing to improve their dynamic range, but this new Sony sensor should give their software a much better foundation to work with.
Sony has yet to say how close it is to mass production of its new sensors, but has clarified that its new dual-layer transistor pixel technology “will help achieve more and more images of high quality such as smartphone photographs “.
This is important because Sony is by far the largest manufacturer of smartphone camera sensors. According to Statistical figures, it has 42% of the global image sensor market, and recent iPhone 13 Pro Max teardowns show it uses three Sony IMX 7-series sensors.
The new sensor could be good news for mirrorless cameras as well, but the gains will likely be greatest for sensors in smaller smartphones – and that’s apparently where Sony is focusing its attention to begin with.
Analysis: an ideal technological leap for smartphones
The big problem that camera phones struggle with is getting enough light on their sensors, without the handset itself being the size of a brick. Recently, sweeping improvements in multi-frame processing have been the solution, but this new Sony sensor might be the first major hardware leap we’ve seen in some time.
On the new Sony Xperia Pro-I, we saw Sony use a 1-inch sensor in one of its phones for the first time. But it also revealed the limitations of using the old-school approach of using larger sensors to collect more light. The Xperia Pro-I only uses a 12 MP portion of that 20.1 MP sensor – a phone that uses the entire 1 inch sensor would likely be prohibitively thin.
This is why this new stacked sensor is ideal for smartphones. It offers drastically improved light collecting powers over current CMOS sensors, but without significantly increasing the size of the chip itself.
So-called “stacked” sensors have also made great strides in mirrorless cameras. Sony was the pioneer again here too, with the Sony A9 becoming the first full frame camera to have a stacked chip in 2017. In this case, the breakthrough of the stacked design added a new layer of DRAM to the sensor itself, which considerably improved its reading speeds.
This technology has fueled the recent wave of flagship mirrorless cameras, which offer blazingly fast burst speeds and 8K video powers – with the Nikon Z9 even being able to dispense with its mechanical shutter entirely, thanks to improvements to shutters. electronics by stacked sensors.
But the benefits of Sony’s new dual-layer transistor pixels are likely to be more in the areas of improved dynamic range and reduced noise for smartphones – and if this technology has as big an impact as camera sensors without it. mirror from Sony, it could feed another image quality. jump for new generation phones.