Editing Foveon X3 sensor (section)

{{Short description|Digital camera image sensor}}
{{use American English|date=February 2020}}
{{use mdy dates|date=February 2020}}

The '''Foveon X3 sensor''' is a digital camera [[image sensor]] designed by [[Foveon|Foveon, Inc.]], (now part of [[Sigma Corporation]]) and manufactured by Dongbu Electronics.<ref>
[http://www.foveon.com/files/F13_Dongbu_PressRelease_final.pdf Foveon Announces New Image Sensor Manufacturing Partner: Dongbu Electronics of Seoul, South Korea]. Retrieved Jan. 18, 2014.</ref> 
It uses an array of photosites that consist of three vertically stacked [[photodiodes]]. Each of the three stacked photodiodes has a different [[spectral sensitivity]], allowing it to respond differently to different [[wavelength]]s.<ref name="Rush and Hubel">{{cite journal|author=A. Rush|author2=P. Hubel|url=https://www.jstage.jst.go.jp/article/photogrst1964/66/1/66_1_57/_pdf|title=X3 Sensor Characteristics|journal=J. Soc. Photogr. Sci. Technol. Japan|date=2003|volume=66|issue=1|pages=57–60|access-date=March 6, 2007}}</ref> The signals from the three photodiodes are then processed as [[additive color]] data that are transformed to a standard [[RGB color space]]. In the late 1970s, a similar color sensor having three stacked photo detectors at each pixel location, with different spectral responses due to the differential absorption of light by the semiconductor, had been developed and patented by Kodak.<ref>{{Cite patent|number=US4613895A|title=Color responsive imaging device employing wavelength dependent semiconductor optical absorption|gdate=1986-09-23|invent1=Burkey|invent2=VanHeyningen|invent3=Spaulding|invent4=Wolf|inventor1-first=Bruce C.|inventor2-first=Roger S.|inventor3-first=Richard A.|inventor4-first=Edward L.|url=https://patents.google.com/patent/US4613895A/en}}</ref>  

The X3 sensor technology was first deployed in 2002 in the [[Sigma SD9]] [[Digital single-lens reflex camera|DSLR]] camera, and subsequently in the [[Sigma SD10|SD10]], [[Sigma SD14|SD14]], [[Sigma SD15|SD15]], [[Sigma SD1|SD1 (including SD1 Merrill)]], the original mirrorless compact [[Sigma DP1]] and [[Sigma DP2]] in 2008 and 2009 respectively, the [[Sigma dp2 Quattro]] series from 2014, and the Sigma SD Quattro series from 2016. The development of the Foveon X3 technology is the subject of the 2005 book ''The Silicon Eye'' by [[George Gilder]].