This relates generally to imaging devices, and more particularly, to imaging devices with color filter barriers.
Modern electronic devices such a cellular telephones, cameras, and computers often use digital image sensors. Imagers (i.e., image sensors) may be formed from a two-dimensional array of image sensing pixels. Each pixel may include a photosensor such as a photodiode that receives incident photons (light) and converts the photons into electrical signals. Image sensors are sometimes designed to provide images to electronic devices using a Joint Photographic Experts Group (JPEG) format or any other suitable image format.
Imagers may be provided with color filter arrays. A color filter array may include an array of color filters formed over an array of photosensors. Each color filter in the color filter array may be optimized to pass a given wavelength band of the electromagnetic spectrum. For example, a color filter array may include red color filters which are optimized to pass a wavelength band corresponding to red light, blue color filters which are optimized to pass a wavelength band corresponding to blue light, and green color filters which are optimized to pass a wavelength band corresponding to green light. Various interpolation and signal processing schemes may be used to construct a full-color image using the image data which is gathered from an imager having a color filter array.
In addition to capturing images of a scene, some imagers may be capable of performing other functions. Imagers sometimes include application-specific pixels which are capable of performing specific functions and are not necessarily used for capturing images. Application-specific pixels may be formed adjacent to imaging pixels. If care is not taken, the presence of application-specific pixels in an array of imaging pixels may exacerbate optical crosstalk in an imager. For example, optical crosstalk that occurs between an imaging pixel and an adjacent application-specific pixel may be more difficult to correct than optical crosstalk between adjacent imaging pixels.
It would therefore be desirable to be able to provide imaging devices with color filter barriers for reducing optical crosstalk.