Sony has announced a 48-megapixel sensor for smartphone cameras, the highest resolution sensor in such a small package to date.

For those who don't know, Sony produces a lot of the sensors that go into smartphone cameras, with many of the leading phones choosing Sony sensors to power their cameras - in fact, Sony sells a lot more sensors than they do smartphones. 

A 48-megapixel camera in a phone might sound like a silly idea, but we've seen a couple of examples of high resolution sensors being put to good use in recent smartphones. It's not about taking huge images, it's about increasing the functions that the smartphone camera offers. 

In many cases, higher resolution sensors are designed to enable digital zoom and that's one of the functions that Sony is pushing with its new IMX586 sensor. The idea is that you can crop the sensor, taking a zoomed image but still have the resolution to provide the detail.

SonySonys 48-megapixel Sensor Could Super-charge Smartphone Cameras Of The Future image 2

One of the "world's first" claims on the new sensor is that it has the smallest pixels - at 0.8µm. Generally speaking, the accepted truth is that larger pixels are better than smaller pixels, because they let more light in. 

To counter this, Sony talks up its pixel combining technology, which it says equates to 1.6µm at 12-megapixels. Pixel combining is a common thing on the most recent smartphone cameras - it's one of the elements of the LG G7's Super Bright camera, for example. At 1.6µm as a combined pixel, you'll still be able to get a 12-megapixel photo where the LG G7's image would be reduced to 4 megapixels.

Finally, Sony says that this sensor is better placed for HDR capture because it has a four times great dynamic range than other sensors. HDR is a hot trend at the moment.

Of course, it's not only the sensor that makes the camera - there's the quality of the lens, the aperture and a whole lot of digital signal processing, both from Sony and from the phone manufacturer which results in the final product. 

Naturally, this is a stacked sensor, meaning that the DRAM is combined with the sensor to give it processing power, like Sony's other recent sensors, so HDR video and super-slow motion are all likely to be possible.

Sony says that testing samples will be available from September 2018; could this sensor be heading into 2019's smartphones? We'll have to wait and see.