Display panel and display device including the same
The present disclosure provides a display panel including a display area including a first pixel area and a second pixel area in which a plurality of pixels are disposed, an optical sensor disposed to overlap the second pixel area, a plurality of infrared (IR) light sources disposed in the display area, and a driving circuit configured to drive the pixels and the IR light sources, wherein the pixels and the IR light sources alternately emit light to improve the amount of light received from the optical sensor.
1 . A display panel comprising:
a display area including a first pixel area and a second pixel area in which a plurality of pixels are disposed;
an optical sensor overlapping the second pixel area;
a plurality of infrared (IR) light sources in the display area; and
a driving circuit configured to drive the plurality of pixels and the plurality of IR light sources to alternately emit visible light and IR light, respectively,
wherein the driving circuit is configured not to drive the plurality of pixels to emit light during a sensing period during which the driving circuit is configured to drive the IR light sources to emit the IR light, and
wherein the driving circuit is configured to drive the plurality of pixels to display an image during a light emitting period during which the driving circuit is configured not to drive the IR light sources to emit the IR light.
2 . The display panel of claim 1 , wherein the optical sensor includes a light receiving part and a light emitting part and the light receiving part measures light emitted by the light emitting part of the optical sensor and the plurality of IR light sources.
3 . The display panel of claim 1 , wherein the second pixel area includes:
a plurality of pixel groups including the plurality of pixels; and
a light transmitting part between the plurality of pixel groups.
4 . The display panel of claim 3 , wherein pixels per inch (PPI) of pixels from the plurality of pixels disposed in the first pixel area and PPI of the plurality of pixel groups disposed in the second pixel area are different.
5 . The display panel of claim 4 , wherein the PPI of the second pixel area is less than the PPI of the first pixel area.
6 . The display panel of claim 3 , wherein IR light sources from the plurality of IR light sources in the second pixel area are disposed in areas in which the plurality of pixel groups and the light transmitting part are not disposed.
7 . The display panel of claim 3 , wherein each of the plurality of IR light sources is between the plurality of pixel groups in the first pixel area.
8 . The display panel of claim 1 , wherein the driving circuit includes:
a driving element including a first electrode to which a pixel driving voltage is applied, a gate electrode connected to a second node, and a second electrode connected to a third node;
a light emitting element including an anode electrode connected to a fifth node and a cathode electrode connected to a first line to which a pixel base voltage is applied;
a capacitor connected to the second node and a first node;
a fourth switch element connected to the fifth node and a sixth node that is connected to an anode electrode of an IR light source from the plurality of IR light sources, the fourth switch element turned on/off in response to a second (n−1) scan signal (n is a positive integer of 2 or more); and
an IR light source from the plurality of IR light sources that is connected to the first line and a second line to which an IR light source base voltage is applied.
9 . The display panel of claim 8 , wherein the driving circuit further includes:
a first switch element connected to the first node and a third line to which a data voltage is applied, the first switch element supplying the data voltage to the first node in response to a second scan signal;
a second switch element connected to the first node and a fourth node to which a reference voltage is applied, the second switch element supplying the reference voltage to the first node in response to a light emission control signal; and
a third switch element connected to the fourth node and the fifth node, the third switch element supplying the reference voltage to the fifth node in response to a first scan signal.
10 . The display panel of claim 9 , wherein the driving circuit further includes:
a fifth switch element connected to the fifth node and the third node, the first switch element connecting the third node to the anode electrode of the light emitting element in response to the light emission control signal
a sixth switch element connected to the second node and the third node and turned on/off in response to the first scan signal, the sixth switch element connecting the second node and the third node when the sixth switch element is turned on; and
a seventh switch element connected to the sixth node and a fourth line to which an IR light source driving voltage is applied, the seventh switch element applying the IR light source driving voltage to the sixth node in response to the second scan signal.
11 . The display panel of claim 10 , wherein the pixel driving voltage of the driving circuit and the IR light source driving voltage are the same.
12 . The display panel of claim 10 , wherein the pixel driving voltage of the driving circuit and the IR light source driving voltage are different.
13 . The display panel of claim 10 , wherein gate-on voltages of the first switch element to the seventh switch element are set to a voltage greater than the pixel driving voltage, and gate-off voltages of the first switch element to the seventh switch element are less than the pixel base voltage.
14 . The display panel of claim 10 , wherein a driving period of the driving circuit includes an initialization period, the sensing period, and the light emitting period, and
wherein the first scan signal, the second (N−1) scan signal and the light emission control signal are gate-on voltages, and the second scan signal is a gate-off voltage during the initialization period.
15 . The display panel of claim 14 , wherein the first scan signal and the second scan signal are gate-on voltages, and the second (N−1) scan signal and the light emission control signal are gate-off voltages during the sensing period.
16 . The display panel of claim 15 , wherein the light emission control signal is a gate-on voltage, and the first scan signal, the second scan signal and the second (N−1) scan signal are gate-off voltages during the light emitting period.
17 . The display panel of claim 9 , wherein the reference voltage is less than the pixel driving voltage and greater than the pixel base voltage.
18 . The display panel of claim 9 , wherein the reference voltage is greater than a lowest grayscale voltage or black grayscale voltage within a dynamic range of the data voltage.
19 . The display panel of claim 1 , wherein the optical sensor photoelectrically converts light reflected from an external real-world image to capture the external real-world image in a shooting mode or drives an IR light source from the plurality of IR light sources to photoelectrically convert infrared light reflected from a user's face in a facial recognition mode to acquire features of the user's face.
20 . The display panel of claim 1 , wherein the plurality of IR light sources and a plurality of light emitting elements of the plurality of pixels are disposed on a same layer.