20.1 megapixel 1-inch Exmor R BSI-CMOS sensor

The new Sony 1 inch censor is one of the most exciting new features for this camera: a significantly bigger sensor has been integrated within only a slightly increased camera size. So this camera remains very compact while still having a much bigger sensor than its predecessors for capturing images.

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I have found a great video that explains the Exmor-R CMOS sensor:

Here are the main highlights from the video:

• CMOS sensor, unlike the CCD sensor allows data to be read very quickly off the sensor, which further allows features like: high resolution movie recording and very quick capture of images
• Because the CMOS sensor is very quick a feature called "Sweep Panorama" can be used. This is when the camera takes images in one sweep of the camera with automatic position adjustment, and then digitally stitches the images in one big continuous image. This is perfect for capturing big landscape scenes. You can check the wide stadium image in the video using this technique.
• The traditional way of building image sensors is putting the wiring for passing light in front of the sensor, so with small sensors this wiring gets in the way of capturing light. Sony has invented a new way of putting the wiring on the back of the sensor so the transmission of light is no longer blocked. There is a great drawing on the video for you to visually understand this.
• Because of the back-end wiring on the sensor, it becomes more sensitive and this means that in low light conditions images can be captured without flash light or the picture noise is very much reduced resulting in very high quality images (very good explanation of picture noise at around 4:35 of the video).

By increasing the size of the sensor all these features only gain in quality so you can see what an improvement has been done here from previous RX100 series of Sony digital cameras.