Panasonic's Micro Color Splitter could double a camera's color sensitivity
Panasonic has developed a new technology which could replace the color filters used in most digital cameras. Its new Micro Color Splitters work by separating colors at a microscopic scale using diffraction, rather than filtration. This means the technology has the potential to vastly improve low-light photography, and double a camera's color sensitivity.
Since the advent of digital photography, the most common way of producing a color image has been by using a Bayer color filter array on top of an image sensor, which only records light intensity. This means light is filtered into a mosaic pattern of red, blue and green on a pixel level, before being "demosaiced" into a final image with full color information.
However, because light is filtered with this method, somewhere between 50-70 percent of it is blocked from ever reaching the sensor. Panasonic says its development addresses the problem and has "almost no loss of light" because it uses a transparent and highly-refractive plate-like structure. This separates colors at a microscopic scale using diffraction. Layout technologies and algorithms are then used to provide precise color reproduction.
The image on the left was taken using a color filter, while the one on the right used a Micro Color Splitter
The key point of the technology is that the Micro Color Splitters are transparent – allowing a much more efficient use of light. Panasonic claims this means photographs can be taken at half the light levels needed by conventional filters and sensors. While this could mean large-sensor cameras with amazing low light capabilities, it also means devices like smartphones or compact cameras could see vastly increased performance.
Though we don't expect to see Micro Color Splitters deployed in Panasonic cameras any time soon – the research has only just been published in Nature Photonics – it's also noted that they can be produced using current semiconductor manufacturing techniques, and can simply replace the color filters in conventional image sensors, whether CCD or CMOS.
Panasonic says it holds 21 Japanese patents and 16 overseas patents, including pending applications, covering the development.