Patent attributes
An electronic device may have a display with an array of pixels configured to display images for a user. The electronic device may have an ambient light sensor for gathering ambient light information. Control circuitry in the electronic device may adjust the brightness level of an image being displayed by the display based on ambient light measurements from the ambient light sensor. The ambient light sensor may be formed from an ambient light sensor module that is aligned with an opening in an opaque masking layer in the display. One or more antireflection layers may be interposed between an inwardly facing surface of the display and an opposing external surface of the ambient light sensor module. The ambient light sensor module may have a light attenuator and other optical structures.