CCD with 4-color (Red, Green, Blue+ Emerald) filter
 

Tokyo (JCNN) - Sony Corporation (TSE: 6758) today announced the world's first practical consumer (home) use of CCD with 4-color (Red, Green, Blue+ Emerald) filters, together with a new image processor corresponding to the 4-color filter. By this technology, the color reproduction error is halved compared to Sony's conventional 3-primary-color filter CCD and, expression of images closer to the natural sight perception of the human eye is achieved under various shooting conditions.

Conventional digital still cameras mainly use 3-primary-color filter CCD, and the colors are recorded by the intensity of each of the 3 colors, Red(R), Green(G) and Blue(B), corresponding to the color reproduction characteristics of the color TV or monitors. However, the characteristics of these CCD filters are different from those of the human visual system. Color differences therefore emerge compared to natural human sight, resulting in different color reproduction.

In the 4-color filter CCD, a filter with the Emerald (E) color is added to the conventional 3-color RGB filter, in order to reduce the color reproduction errors and to record natural images closer to the natural sight perception of the human eye. As a result, the characteristics of the CCD color filter become much closer to those of the human visual system, achieving dramatic reduction in the color reproduction error.

In addition to the development of the 4 color filter, a new image processor corresponding to the 4-color filter has been developed. With this processor, each of the signals captured by the 4 colors is processed to produce ideal 3 colors close to the natural sight perception the human eye by a matrix calculation. Also, in addition to functioning with 30% less power consumption, by the efficient processor management, functions such as high-speed image shooting and high-speed playback are realized, as well as enhancing the of overall basic functions of digital still cameras.

Sony plans to integrate the newly developed 4 color filter CCD and the new image processor into the new digital cameras which will be introduced in the near future.

Interresting but I have a question; will this new reference color add to the data rate? I guess so. If so it might not be used anytime soon on HDV devices since the data rate is already difficult to maintain with 3 colors... Of course, evolution is always possible and Sony could release a HD format close to HDV of their own soon enough...

Sony supports the HDV format so, unless they use DVD+RW, it will be HDV.

The question is, will it be used for video or only stills.

Of course they support HDV format but so did they support DV and they still developped DVcam soon afterwards. I suppose if results are good with stills they might try video.

Since it was announced in August I've had my beady eye on this upcoming digital camera from Sony which uses the four chip architecture. I liked the feature set, but the new technology under the hood has me intrigued also. Looking forward to seeing some actual stills when the pre-production models are reviewed this month, I think.

<<<-- Originally posted by Charles Papert which uses the four chip architecture. -->>>

I think it's 4 filters on 1 chip.

yes of course. Thanks for the correction Steve.

I remember Sony promoting their 3 CCD sensor system in the past, used on pro video cameras and their subtraction of chroma from luma, claiming that it precisely mimics the human visual functions, which is 3-color, not 4-color.

If I'm not wrong, the new Sony semi-pro digital camera F-828 (successor to F-717) will have this new 4 filter CCD.

> Interresting but I have a question; will this new reference color
> add to the data rate? I guess so.

I don't think so. The extra color is present in the image sensor as a way of capturing a better image in the AD conversion stage, where it is more critical. But once the image is captured, it can be represented in RGB or YUV just like it is today. The difference is the resulting video should have more natural chroma than would have been captured with a 3 color system, at least that seems to be the promise.