Systems, methods, and devices are provided in which photodetectors disposed throughout a display are used to control the display brightness. The photodetectors are to be used for ambient light sensing, proximity sensing, or to compensate for aging OLEDs. In some embodiments, photodiodes are fabricated with OLEDs during the TFT fabrication process. In some embodiments, the photodetectors may be disposed throughout the display in zones containing OLEDs. The photodetectors are used to control the display brightness and color for the OLEDs in areas around each photodetector based on ambient light, aging, and/or nearby objects. A controller makes driving strength adjustments to the OLEDs in each zone independent of other zones. Photodetectors disposed throughout the display may improve proximity sensing and provide additional functionality to the device.