Organic light emitting diode display including sensors
An organic light emitting diode display including a pixel that includes a light-emitting device and a first thin film transistor connected to the light-emitting device; and a sensor that includes a light sensing element, wherein the light sensing element includes a gate electrode; an active layer on the gate electrode; a filter layer on the active layer; and source and drain electrodes on the active layer, the source and drain electrodes being connected to the active layer, the light sensing element and the first thin film transistor are formed on a same substrate, and one of the gate electrode and the active layer of the light sensing element and a gate electrode of the first thin film transistor are aligned on a same layer.
1. An organic light emitting diode display, comprising:
a pixel that includes a light-emitting device and a first thin film transistor connected to the light-emitting device; and
a sensor that includes a light sensing element,
wherein:
the light sensing element includes:
a gate electrode;
an active layer on the gate electrode;
a filter layer on the active layer; and
source and drain electrodes on the active layer, the source and drain electrodes being connected to the active layer,
the light sensing element and the first thin film transistor are formed on a same substrate, and
one of the gate electrode and the active layer of the light sensing element and a gate electrode of the first thin film transistor are aligned on a same layer.
2. The organic light emitting diode display as claimed in claim 1 , wherein:
the first thin film transistor includes:
a polycrystalline semiconductor layer on the substrate;
the gate electrode on the polycrystalline semiconductor layer; and
source and drain electrodes on the gate electrode, the source and drain electrodes being connected to the polycrystalline semiconductor layer, and
the light-emitting device includes:
a pixel electrode overlying the source and drain electrodes and connected to one of the source and drain electrodes;
an organic light emitting layer on the pixel electrode; and
a common electrode on the organic light emitting layer.
3. The organic light emitting diode display as claimed in claim 2 , wherein the source and drain electrodes of the light sensing element:
are aligned on a same layer as the pixel electrode of the light-emitting device, and
are formed of a same material as the pixel electrode.
4. The organic light emitting diode display as claimed in claim 3 , wherein the filter layer and the source and drain electrodes of the light sensing element are aligned on a same layer.
5. The organic light emitting diode display as claimed in claim 2 , wherein the gate electrode of the light sensing element:
is aligned on a same layer as the gate electrode of the first thin film transistor, and
is formed of a same material as the gate electrode of the first thin film transistor.
6. The organic light emitting diode display as claimed in claim 5 , wherein the active layer of the light sensing element is aligned on a same layer as the source and drain electrodes of the first thin film transistor.
7. The organic light emitting diode display as claimed in claim 2 , wherein the gate electrode of the light sensing element:
is aligned on a same layer as the polycrystalline semiconductor layer, and
is formed of a doped polycrystalline semiconductor.
8. The organic light emitting diode display as claimed in claim 7 , wherein the active layer of the light sensing element is aligned on a same layer as the gate electrode of the first thin film transistor.
9. The organic light emitting diode display as claimed in claim 2 , wherein the light-emitting device further includes an infrared emitting layer between the pixel electrode and the organic light emitting layer.
10. The organic light emitting diode display as claimed in claim 2 , wherein:
the sensor further includes a second thin film transistor that includes source and drain electrodes, and
one of the source and drain electrodes of the second thin film transistor is connected to one of the source and drain electrodes of the light sensing element.
11. The organic light emitting diode display as claimed in claim 2 , wherein:
the sensor further includes a capacitor that includes a first electrode and a second electrode,
the first electrode of the capacitor is aligned on a same layer as the semiconductor layer of the first thin film transistor and is formed of a doped semiconductor, and
the second electrode of the capacitor is aligned on a same layer as the gate electrode of the first thin film transistor and is formed of the same material as the gate electrode of the first thin film transistor.
12. The organic light emitting diode display as claimed in claim 1 , wherein the filter layer includes a band-pass filter containing one of poly(methyl methacrylate), polycarbonate, and polyimide.