US Patent 10536652 Image sensors with split photodiodes

An imaging device may have an array of image sensor pixels. Each image sensor pixel of the array of image sensor pixels may have split photodiodes that are symmetric about a shared floating diffusion region. The floating diffusion region may be coupled to each of the photodiodes. Each of the split photodiodes and the floating diffusion region may generate charge in response to light incident on the image sensor pixel. The split photodiodes and the floating diffusion region may be covered by a microlens. The charge generated by the photodiodes and the floating diffusion region may be compared and utilized by the imaging device in phase detection applications. The image sensor pixel may also include a dual conversion gain capacitor and a gain select transistor to produce high dynamic range (HDR) images.