Abstract: An image sensor may include a pixel array with a plurality of image pixels and a plurality of phase detection pixels. The plurality of phase detection pixels may have a greater stack height than the plurality of image pixels. Varying the stack height of pixels in the pixel array may enable the stack height of the image pixels to be optimized for gathering image data while the stack height of the phase detection pixels is optimized to gather phase detection data. A support structure may be used to increase the stack height of the phase detection pixels. The support structure may be formed over a color filter array or one or more microlenses. The support structure may include color filter elements to supplement or replace the color filter elements of the color filter array.