Sony has announced a new smartphone image sensor that promises to produce some seriously impressive camera specifications for some future smartphones. The IMX586 performs some DSP magic on the raw bits from its unusual Bayer color array to arrive at an impressive-sounding 48-effective-megapixel resolution. That kind of resolution is more typical of high-end DSLRs, not handsets. Of course, comparing a DSLR sensor to an eight-millimeter-diagonal smartphone sensor isn't an entirely straightforward comparison, and the IMX586 is no exception.
You see, Sony has filtered the IMX586 with 2×2 arrays of red, blue, and green pixels, rather than the traditional Bayer array of one red, one blue, and two green color filters per 2×2-pixel sub-array. The company says this “quad-Bayer” approach lets it pull off two tricks. In good lighting conditions, Sony's DSP magic conceptually lets the sensor perform array conversion on the raw pixel data to a traditional Bayer mosaic before further processing. That conversion is how the company arrives at that 48-MP effective resolution. In darker scenes, the data from the sensor simply isn't converted, resulting in a 12-MP effective sensor that Sony says has the light-gathering power of 1.6-µm sensor wells.
IMX586 sample on the right. Image: Sony
High resolutions on tiny sensors usually mean disappointingly noisy images, but Sony claims that the industry-first 0.8-µm bit buckets on the IMX586 were “designed and manufactured with techniques that improve light collection efficiency and photoelectric conversion efficiency over conventional products,” possibly leading to crisp images despite the tiny individual pixel wells. Indeed, the single sample that Sony shared offers noticeably higher resolution while keeping noise levels low, although the image was clearly taken in sensor-friendly broad daylight. I'll be curious to see results from the IMX586 in a wider range of lighting conditions.
The IMX586 has a range of other interesting raw specifications, like DCI 4K video recording at 90 FPS, 1920×1080 at 240 FPS, and a cropped 720p capture at 480 FPS. Of course, smartphone makers will need to integrate image signal processors and buffers capable of handling more than a few seconds of footage at those frame rates in their finished product, but the sensor does sound like an impressive starting point.
Sony plans to begin sampling the IMX586 to customers in September at a price of 3000 yen, or about $27 at today's exchange rates. Shipping products with this sensor inside will likely begin appearing sometime next year.