Panasonic promises high sensitivity sensors using 'Micro Color Splitters'
Panasonic has devised a method to increase the sensitivity of image sensors, by replacing the near-universal colour filter array with prism-like 'Micro Color Splitters' to generate colour information. The key advantage is that all of the incoming light is directed to the sensor, instead of half or more being absorbed by the colour filter dyes. This promises to deliver images with less noise in low light. The development is published in the journal Nature Photonics, and outlined in a press release on Panasonic's website.
According to Panasonic, the dyes used in conventional colour filter arrays absorb at least half of the incoming light before it reaches the sensor's photosites. In contrast, the company's 'Micro Color Splitter' technology passes all of the incoming light to the sensor. In practical terms, this corresponds to a sensitivity increase of a whole stop, which should in turn result in a stop improvement in noise performance. In other words, a 'Micro Color Splitter'-based sensor should give similar noise at ISO 3200 as a conventional Bayer sensor does at ISO 1600, for example.
Perhaps the most interesting aspect of this development is that it may be the first serious alternative to colour filter array-based sensors since the Foveon X3 appeared over 10 years ago. Like any new technology there'll be plenty of development to do before it appears in a real product, but the prospect of a stop better high ISO performance is certainly a tantalising one.
Panasonic Develops Technology for Highly Sensitive Image Sensors Using Micro Color Splitters
|Constitution and features compared with the conventional method|
Osaka, Japan - Panasonic Corporation has developed unique "micro color splitters", which separate the light that falls on image sensors by exploiting light's wavelike properties. Applying them to actual image sensors allows bright color images to be achieved even under low-light conditions. This development makes color filters unnecessary by using the micro color splitters that control the diffraction of light at a microscopic level. Panasonic has achieved approximately double the color sensitivity in comparison with conventional sensors that use color filters.
Image sensors are used in devices like smartphones, digital still cameras and video cameras, as well in security, vehicle parking, office, and healthcare applications - anywhere, in fact, that digital imaging is needed. Conventional color image sensors use a Bayer array, in which a red, green, or blue light-transmitting filter is placed above each sensor. These filters block 50 - 70% of the incoming light before it even reaches the sensor. Progress is being made in increasing the resolution of image sensors used in mobile and other devices by reducing pixel size, but demand for higher-sensitivity cameras is also increasing. Panasonic has developed a new technology that can be applied to existing or future sensors to enable them to capture uniquely vivid color images.
The developed technology has the following features.
- Using color alignment, which can use light more efficiently, instead of color filters, vivid color photographs can be taken at half the light levels needed by conventional sensors.
- Micro color splitters can simply replace the color filters in conventional image sensors, and are not dependent on the type of image sensor (CCD or CMOS) underneath.
- Micro color splitters can be fabricated using inorganic materials and existing semiconductor fabrication processes.
This development is based on the following new technology.
- A unique method of analysis and design based on wave optics that permits fast and precise computation of wave-optics phenomena.
- Device optimization technologies for creating micro color splitters that control the phase of the light passing through a transparent and highly-refractive plate-like structure to separate colors at a microscopic scale using diffraction.
- Layout technologies and unique algorithms that allow highly sensitive and precise color reproduction by combining the light that falls on detectors separated by the micro color splitters and processing the detected signals.
Panasonic holds 21 Japanese patents and 16 overseas patents, including pending applications, for this development.
This development is described in general terms in the Advance Online Publication version of Nature Photonics issued on February 3, 2013.
More on the Technology
|Conventional method using a color filter||Developed method using a micro color splitter|
1. Unique method of analysis and design based on wave optics permitting fast and precise computation of wave-optics phenomena
FDTD is widely used to analyze light in wave form, but its heavy computation workload has up to now made it impractical for designing micro color splitters. On the other hand, BPM is an effective method of fast computation, but it has lower precision than FDTD and cannot accurately simulate color splitting. This prompted Panasonic to develop a practical and original design method that permits fast and precise computation of wave-optics phenomena. This technology allows the precise modeling of optical phenomena such as reflection, refraction, and diffraction by modeling spaces in regions with different optical constants and applying BPM to the spaces. This method can be applied not only to the design of micro color splitters, but can be extended to the design of other nano-scale optical processing systems.
2. Device optimization technologies leading to the creation of micro color splitters that control the phase of the light passing through a transparent and highly-refractive plate-like structure and use diffraction to separate colors on a microscopic scale
Color separation of light in micro color splitters is caused by a difference in refractive index between a) the plate-like high refractive material that is thinner than the wavelength of the light and b) the surrounding material. Controlling the phase of traveling light by optimizing the shape parameters causes diffraction phenomena that are seen only on a microscopic scale and which cause color separation. Micro color splitters are fabricated using a conventional semiconductor manufacturing process. Fine-tuning their shapes causes the efficient separation of certain colors and their complementary colors, or the splitting of white light into blue, green, and red like a prism, with almost no loss of light.
3. Layout technologies and unique algorithms that enable highly sensitive and precise color reproduction by overlapping diffracted light on detectors separated by micro color splitters and processing the detected signals
Since light separated by micro color splitters falls on the detectors in an overlapping manner, a new pixel layout and design algorithm are needed. The layout scheme is combined and optimized using an arithmetic processing technique designed specifically for mixed color signals. The result is highly sensitive and precise color reproduction. For example, if the structure separates light into a certain color and its complementary color, color pixels of white + red, white - red, white + blue, and white - blue are obtained and, using the arithmetic processing technique, are translated into normal color images without any loss of resolution.
- 1. Diffraction
- Behavior of light as a wave on the wavelength (nanometer) scale. Various phenomena occur when a wave encounters an obstacle.
- 2. Bayer array
- The arrangement of color filters used in most single-chip digital imaging sensors used in digital cameras, camcorders, and scanners to create a color image. The filter pattern is 50% green, 25% red and 25% blue.
- 3. Charge Coupled Device Image Sensor (CCD sensor)
- A type of solid-state image sensing device for digital imaging, used in digital video cameras of all types. It has higher sensitivity and lower noise than other sensing devices.
- 4. Complementary Metal Oxide Semiconductor Image Sensor (CMOS sensor)
- A solid-state image sensing device for digital imaging using CMOS.
- 5. Finite-Difference Time-Domain method (FDTD)
- FDTD is a versatile modeling technique used to solve Maxwell's equations by spatial and temporal discretization.
- 6. Beam Propagation Method (BPM)
- A numerical analysis technique in electromagnetics for solving the Helmholtz equation under conditions of a time-harmonic wave.
Jan 20, 2016
Jan 5, 2016
Jan 5, 2016
Jan 5, 2016
This simple photograph of a seahorse and Q-tip has taken the internet by storm. We spoke to photographer Justin Hofman about how it was captured, and what it means to him.
After a massive leak last week, Profoto has officially debuted the Profoto A1: the company's first on-camera flash system that they're calling "the world's smallest studio flash."
"When the first hyperfocal distance charts were designed, someone decided that an acceptably sharp background contained some blur — enough to notice in a medium-sized print [...] After that point, nearly every other hyperfocal chart followed suit."
The Canon EOS Rebel SL2 (also known as the EOS 200D) is the company's impressively compact entry-level DSLR. Packing a 24MP APS-C sensor, DIGIC 7 processor and Dual Pixel AF, it promises a lot of bang for the buck. And while not mind-blowing, it handles most tasks very well.
Correct these four common composition mistakes and your photos will be more balanced, tell a better story, and lead your viewer's eye where you want it to go.
The rugged, compact 360° action camera Kodak unveiled at Photokina in 2016, the Kodak PixPro Orbit 360, is finally available in the United States.
iOS 11 launches tomorrow, and it'll save all of your pictures in a new high efficiency image format called HEIC. Fortunately, there's now a converter that will let you turn those photos back into JPEGs.
Photo protection company ImageRights recently released a new service that lets non-subscribers take advantage of their streamlined copyright registration system that checks for errors and fills out all the required forms for you.
What's the difference between a $200 circular polarizing filter and a $100 circular polarizing filter? Roger Cicala at Lens Rentals put six different filters through a few tests to find out.
A flurry of leaks reveal that GoPro's upcoming Hero6 will shoot 4K at 60fps, 1080p at 240fps, will cost $500, and is scheduled for announcement/release on September 28th.
Before he became the iconic director whose name we've all heard, a teenage Stanley Kubrick struck up a business relationship with New York’s Look magazine. No surprise: he was an incredibly talented photographer.
WD's new G-Technology G-Drive mobile SSD R-Series is a portable solid state option for photographers who want the reliability of an SSD in a rugged water and dust-resistant package.
Fast, stabilized and affordable is an appealing combination when it comes to lenses. With its latest 24-70mm F2.8, Tamron aims to upgrade autofocus speed and stabilization. We've got a full gallery from this updated full-frame zoom.
Photographer Clay Cook tells the story of his most ambitious photographic dream and career goal coming true: photographing A-list actress Jennifer Lawrence.
In an interview with a Chinese website, Nikon Japan's Director of Development dropped a bombshell, saying that a Nikon mirrorless camera "must be full-frame."
Here's a side-by-side spec comparison of two flagship devices with particular attention to the things that really matter – at least to people who prioritize photography features.
A month and a half after revealing the finalists of the 2017 EyeEm Awards, the photo sharing community and licensing marketplace has finally revealed the winners.
Photographer Josselin Cornou tells the breathtaking story behind two beautiful photos captured while snorkeling with humpback whales in Tonga.
The Sony RX10 IV is a fixed lens camera with a 1"-type sensor and 24-600mm equivalent lens that can shoot 4K video or stills at 24 fps, but that's not what we think is interesting about it. The addition of phase detection autofocus is pivotal to all those features.
The announcement date is set! Google will reveal their next generation Pixel phones—their response to Apple's shiny new iPhone X—on October 4th. Let the smartphone camera wars begin.
Sony just debuted three palm-style 4K camcorders that steal a bit of speedy phase detect autofocus technology from the company's RX10 IV. In fact, they kind of improve on it.
Earlier today, NASA's Cassini spacecraft plunged into Saturn's atmosphere, ending a 20 year long mission. Here are 21 of our favorite photographs captured by this incredible machine and its makers.
Fans of film photography should keep an eye out for the widespread theatrical release of Kodachrome, a movie staring Jason Sudeikis about the final days of the iconic film stock.
Photographer Manny Ortiz breaks down the pros and cons of shooting natural light vs off-camera flash, and explains why he chooses to shoot one, the other, or both in any given situation.
A leaked product page and a bunch of leaked photos shows Profoto is preparing to release its first ever speedlight: the Profoto A1 Air TTL
The Yashica camera brand disappeared in 2003, but a new teaser video and website hint at a comeback. Excited?
Western Digital just debuted a new, higher capacity WD Gold internal hard drive. The new drive offers 12TB of storage and class-leading reliability to the tune of a 550TB/year workload rating.
The new Godox XPRO-C is an affordable, highly capable flash trigger for Canon users that boasts a lot of useful features at a very reasonable price.
Tamron is working on a lightweight, durable and compact 100-400mm tele-zoom lens that will be available for Canon and Nikon cameras by the end of the year.
The Nikon D850 promises equal parts resolution and speed. On a trip to Bend, Oregon, we had the chance to try it out with fashion, sports, landscapes, and more. Check out our updated sample gallery to see how it fared.