A display, comprising: an active matrix organic light emitting diode (AMOLED) panel having a plurality of pixels arranged in an array, each pixel comprising: (a) an organic light emitting diode having a cathode electrically coupled to a first supply voltage (OVSS), a anode and an emissive layer formed between the cathode and the anode; (b) a driving circuit having: (i) a first transistor having a gate, a drain electrically coupled to a second supply voltage( OVDD) and a source electrically coupled to the anode of the organic light emitting diode; (ii) a second transistor having a gate electrically coupled to a scan signal (Vscan), a drain electrode electrically coupled to the gate of the first transistor, and a source electrode electrically coupled to a data signal (Vdata); and (iii) a storage capacitor (Cst) electrically connected between the gate and the drain of the first transistor; (c) a read-out transistor having a gate electrically a sensing control voltage (Vsense), a drain for outputting a sensing signal (Isense), and a source; and (d) a photo sensor characterized in that the photo sensor is electrically coupled between the anode of the organic light emitting diode and the source of the read-out transistor, wherein the photo sensor is adapted for measuring brightness of an ambient light that is proportional to light emitted from the organic light emitting diode and for generating a sensing signal (Vbias) corresponding to the measured brightness of the ambient light, wherein the data signal (Vdata) is adjusted according to the sensing signal (Vbias). an active matrix organic light emitting diode (AMOLED) panel having a plurality of pixels arranged in an array, each pixel comprising: (a) an organic light emitting diode having a cathode electrically coupled to a first supply voltage (OVSS), a anode and an emissive layer formed between the cathode and the anode; (b) a driving circuit having: (i) a first transistor having a gate, a drain electrically coupled to a second supply voltage( OVDD) and a source electrically coupled to the anode of the organic light emitting diode; (ii) a second transistor having a gate electrically coupled to a scan signal (Vscan), a drain electrode electrically coupled to the gate of the first transistor, and a source electrode electrically coupled to a data signal (Vdata); and (iii) a storage capacitor (Cst) electrically connected between the gate and the drain of the first transistor; (c) a read-out transistor having a gate electrically a sensing control voltage (Vsense), a drain for outputting a sensing signal (Isense), and a source; and (d) a photo sensor (a) an organic light emitting diode having a cathode electrically coupled to a first supply voltage (OVSS), a anode and an emissive layer formed between the cathode and the anode; (b) a driving circuit having: (i) a first transistor having a gate, a drain electrically coupled to a second supply voltage( OVDD) and a source electrically coupled to the anode of the organic light emitting diode; (ii) a second transistor having a gate electrically coupled to a scan signal (Vscan), a drain electrode electrically coupled to the gate of the first transistor, and a source electrode electrically coupled to a data signal (Vdata); and (iii) a storage capacitor (Cst) electrically connected between the gate and the drain of the first transistor; (i) a first transistor having a gate, a drain electrically coupled to a second supply voltage( OVDD) and a source electrically coupled to the anode of the organic light emitting diode; (ii) a second transistor having a gate electrically coupled to a scan signal (Vscan), a drain electrode electrically coupled to the gate of the first transistor, and a source electrode electrically coupled to a data signal (Vdata); and (iii) a storage capacitor (Cst) electrically connected between the gate and the drain of the first transistor; (c) a read-out transistor having a gate electrically a sensing control voltage (Vsense), a drain for outputting a sensing signal (Isense), and a source; and (d) a photo sensor characterized in that the photo sensor is electrically coupled between the anode of the organic light emitting diode and the source of the read-out transistor, wherein the photo sensor is adapted for measuring brightness of an ambient light that is proportional to light emitted from the organic light emitting diode and for generating a sensing signal (Vbias) corresponding to the measured brightness of the ambient light, wherein the data signal (Vdata) is adjusted according to the sensing signal (Vbias).