Sony sensor tech. Image source: VLSI Symposia tipsheet
A couple of weeks ago I showed you two patents describing a Full Frame curved sensor and a 35mm f/1.8 lens designed for such a sensor. Usually when you see Sony patents you well know that it could take ages to see it applied on a real world mass product. Well this could be one of the few cases where a patent becomes “real” in a very short time.
First of all the prestigious site Nikkei Japan reports that Sony has developed a curved sensor that doubles the sensor sensitivity. And Nikkei doesn’t spread a news based on patent :) It means Sony is really ready to launch that kind of tech!
“Curved CMOS Image System: When light transmitted by a lens strikes a perpendicular target such as a CMOS image sensor, it forms a circle of light called an image circle. It’s difficult for a flat (planar) CMOS image sensor to deliver high image sensitivity at high resolution (highly scaled pixel pitch) because of the fundamental physical limit known as quantum efficiency. To break through that physical limit and to achieve higher sensitivity anywhere within the image circle at higher resolution, Sony built and will describe an imaging system that comprises a hemispherically curved, back-illuminated CMOS image sensor (BIS) and integrated lens. It doubles the sensitivity at the edge of the image circle while increasing sensitivity at its center by a factor of 1.4, with a 5x reduction of dark current (Jd) compared to a planar BIS. Moreover, a common problem known as lens field curvature aberration (Afc) is mitigated by the curved sensor itself, and so the curved BIS enables higher system sensitivity with a brighter lens with a smaller F number (Fn) than is possible with a planar BIS. In addition, by controlling the tensile stress of the BIS chip to produce a curved shape in the first place, the energy band-gap (Eg) is widened and a lower Jd is achieved. (Paper T2.1, “A Novel Curved CMOS Image Sensor Integrated with Imaging System,” K. Itonaga et al., Sony)“
And as you know an anonymous source said the RX2 with curved sensor tech and 35mm f/1.8 lens will be announced in summer. it has to be seen if Sony can use such a curved sensor on an interchangeable E-mount camera…