An image sensor may include an array of pixels. Pixels in the array may include a photodiode that converts incident light into electrical charge and a charge storage region for storing the electrical charge before it is read out from the pixel. Pixels in the array may include a microlens formed over the photodiode that directs light onto the photodiode. Pixels in the array may include an additional array of microlenses between the microlens and the photodiode. The additional array of microlenses may direct light away from the charge storage region to prevent charge stored at the charge storage region from being affected by light that is not incident upon the photodiode. The image sensor may be a backside illuminated image sensor that operates in a global shutter mode.