Display device and display panel
The invention provides a display device and a display panel. The display device includes the display panel and a reading circuit. The display panel includes an upper substrate, a lower substrate, a thin-film transistor (TFT) layer, and a photosensitive circuit. The TFT layer is disposed between the upper substrate and the lower substrate. A plurality of TFTs of a pixel array of the display panel are disposed in the TFT layer. The photosensitive circuit is disposed in the TFT layer to sense an ambient light. The reading circuit is coupled to the photosensitive circuit to read a sensing result.
1 . A display panel, comprising:
an upper substrate;
a lower substrate;
a color filter film;
a thin-film transistor layer disposed between the upper substrate and the lower substrate, wherein a plurality of thin-film transistors of a pixel array of the display panel are disposed in the thin-film transistor layer;
a polarizing film disposed between the upper substrate and the thin-film transistor layer, wherein the color filter film is disposed between the polarizing film and the thin-film transistor layer; and
a photosensitive circuit disposed in the thin-film transistor layer and configured to sense an ambient light, wherein the photosensitive circuit comprises:
a photosensitive element configured to sense the ambient light to determine a photocurrent flowing through the photosensitive element, wherein a reading circuit reads the photocurrent of the photosensitive element to learn about the ambient light, and the ambient light passes through the color filter film before being sensed by the photosensitive element.
2 . The display panel of claim 1 , wherein the upper substrate comprises a cover glass, and the lower substrate comprises a polyimide film and a polyester film.
3 . The display panel of claim 1 , wherein the photosensitive circuit is disposed at an edge portion of the display panel.
4 . The display panel of claim 1 , wherein the photosensitive circuit comprises:
a photosensitive element configured to sense the ambient light to determine a photocurrent flowing through the photosensitive element; and
a load coupled to the photosensitive element to convert the photocurrent into a photovoltage, wherein a reading circuit reads the photovoltage to learn about the ambient light.
5 . The display panel of claim 4 , wherein the load comprises:
a transistor having a first terminal coupled to a power voltage, wherein a second terminal of the transistor is coupled to the photosensitive element, and a control terminal of the transistor is coupled to the second terminal of the transistor.
6 . The display panel of claim 4 , wherein the load comprises:
a transistor having a first terminal coupled to a power voltage, wherein a second terminal of the transistor is coupled to the photosensitive element, and a control terminal of the transistor is coupled to a bias voltage.
7 . The display panel of claim 4 , wherein the load comprises:
a resistor having a first terminal coupled to a power voltage, wherein a second terminal of the resistor is coupled to the photosensitive element.
8 . The display panel of claim 1 , wherein the photosensitive circuit comprises:
a photosensitive element configured to sense the ambient light to determine a photocurrent flowing through the photosensitive element, wherein the photosensitive element is a photosensitive thin-film transistor.
9 . The display panel of claim 1 , wherein the photosensitive circuit comprises:
a photosensitive element configured to sense the ambient light to determine a photocurrent flowing through the photosensitive element, wherein the photosensitive element is a gap-type thin-film transistor, and a gate length of the gap-type thin-film transistor is less than a channel length between a source and a drain of the gap-type thin-film transistor.
10 . A display device, comprising:
a display panel comprising an upper substrate, a lower substrate, a thin-film transistor layer, a color filter film and a photosensitive circuit, wherein the thin-film transistor layer is disposed between the upper substrate and the lower substrate, a plurality of thin-film transistors of a pixel array of the display panel are disposed in the thin-film transistor layer, a polarizing film is disposed between the upper substrate and the thin-film transistor layer, the color filter film is disposed between the polarizing film and the thin-film transistor layer, and the photosensitive circuit is disposed in the thin-film transistor layer to sense an ambient light; and
a reading circuit coupled to the photosensitive circuit to read a sensing result, wherein the photosensitive circuit comprises:
a photosensitive element configured to sense the ambient light to determine a photocurrent flowing through the photosensitive element, wherein the reading circuit reads the photocurrent of the photosensitive element to learn about the ambient light, and the ambient light passes through the color filter film before being sensed by the photosensitive element.
11 . The display device of claim 10 , wherein the upper substrate comprises a cover glass, and the lower substrate comprises a polyimide film and a polyester film.
12 . The display device of claim 10 , wherein the photosensitive circuit is disposed at an edge portion of the display panel.
13 . The display device of claim 10 , wherein the reading circuit comprises:
an amplifier having a first input terminal coupled to a reference voltage, wherein a second input terminal of the amplifier is coupled to the photosensitive element; and
a resistor having a first terminal coupled to the second input terminal of the amplifier, wherein a second terminal of the resistor is coupled to an output terminal of the amplifier.
14 . The display device of claim 10 , wherein the reading circuit comprises:
a current source;
a resistor having a first terminal coupled to a power voltage; and
a current mirror having a master current terminal coupled to the current source and the photosensitive element, wherein a slave current terminal of the current mirror is coupled to a second terminal of the resistor.
15 . The display device of claim 10 , wherein the reading circuit comprises:
a first current source;
a second current source;
a current mirror, wherein a first terminal of a master current path of the current mirror is coupled to the first current source, a first terminal of a slave current path of the current mirror is coupled to the second current source, and a second terminal of the slave current path of the current mirror is coupled to the photosensitive element;
a first transistor having a first terminal coupled to a second terminal of the master current path of the current mirror, wherein a second terminal of the first transistor is coupled to a reference voltage, and a control terminal of the first transistor is coupled to a control voltage;
a second transistor having a first terminal coupled to the second terminal of the slave current path of the current mirror, wherein a second terminal of the second transistor is coupled to the reference voltage, and a control terminal of the second transistor is coupled to the control voltage;
a resistor having a first terminal coupled to a power voltage; and
a third transistor having a first terminal coupled to a second terminal of the resistor, wherein a second terminal of the third transistor is coupled to the second terminal of the master current path of the current mirror, and a control terminal of the third transistor is coupled to the first terminal of the slave current path of the current mirror.
16 . The display device of claim 10 , wherein the photosensitive circuit comprises:
a photosensitive element configured to sense the ambient light to determine a photocurrent flowing through the photosensitive element; and
a load coupled to the photosensitive element to convert the photocurrent into a photovoltage,
wherein the reading circuit reads the photovoltage to learn about the ambient light.
17 . The display panel of claim 16 , wherein the load comprises:
a transistor having a first terminal coupled to a power voltage, wherein a second terminal of the transistor is coupled to the photosensitive element and the reading circuit, and a control terminal of the transistor is coupled to the second terminal of the transistor.
18 . The display panel of claim 16 , wherein the load comprises:
a transistor having a first terminal coupled to a power voltage, wherein a second terminal of the transistor is coupled to the photosensitive element and the reading circuit, and a control terminal of the transistor is coupled to a bias voltage.
19 . The display panel of claim 16 , wherein the load comprises:
a resistor having a first terminal coupled to a power voltage, wherein a second terminal of the resistor is coupled to the photosensitive element and the reading circuit.
20 . The display device of claim 16 , wherein the reading circuit comprises:
an amplifier having a first input terminal coupled to the photosensitive element and the load to receive the photovoltage, wherein a second input terminal of the amplifier is coupled to an output terminal of the amplifier.
21 . The display device of claim 10 , wherein the photosensitive circuit comprises:
a photosensitive element configured to sense the ambient light to determine a photocurrent flowing through the photosensitive element, wherein the photosensitive element is a photosensitive thin-film transistor.
22 . The display device of claim 10 , wherein the photosensitive circuit comprises:
a photosensitive element configured to sense the ambient light to determine a photocurrent flowing through the photosensitive element, wherein the photosensitive element is a gap-type thin-film transistor, and a gate length of the gap-type thin-film transistor is less than a channel length between a source and a drain of the gap-type thin-film transistor.