CROSS REFERENCE TO RELATED APPLICATIONS

This application is the National Stage of PCT/CN2019/098725 filed on Jul. 31, 2019, the disclosure of which is incorporated by reference.

TECHNICAL FIELD

Embodiments of the present disclosure relate to a photoelectric detection circuit, a photoelectric detection device and an electronic device.

BACKGROUND

With the development of science and technology and improvements of life, more and more intelligent terminals are entering people's daily life, including for example, smart phones, tablets and liquid crystal TVs. For intelligent terminals with display screens, maintaining high brightness for a long time will increase energy consumption, while displaying under low brightness in environments with strong lighting will impact image quality and users' comfortability.

Therefore, intelligent terminals with display screens generally use ambient light sensors to sense ambient light and inform the processing chips to adjust backlight brightness of the displays automatically so as to reduce power consumption of the products. For example, in applications of handheld mobile devices such as smartphones, tablet computers and global positioning system (GPS) devices, displays consume up to 30% energy of batteries, while using ambient light sensors may lengthen runtime of batteries in a large extent. On the other hand, ambient light sensors help displays to provide soft displayed images. When the ambient brightness is high, displays using ambient light sensors will be adjusted to high brightness automatically. When the external environment is dark, the display will be adjusted to low brightness.

SUMMARY

At least one embodiment of this disclosure provides a photoelectric detection circuit, comprising: a first detection sub-circuit configured to be exposed to an environment of light to be detected and having an equivalent resistance that varies with a variation of illumination intensity of the light to be detected; a second detection sub-circuit configured to be in a state of fixed illumination intensity and having an equivalent resistance that is constant due to the fixed illumination intensity; and a signal output lead, wherein the first detection sub-circuit is connected in series with the second detection sub-circuit via a first node and the signal output lead is electrically connected with the first node to output detected electrical signals.

For example, in the photoelectric detection circuit provided in the at least one embodiment of this disclosure, the first detection sub-circuit comprises a first photoelectric sensing element, the second detection sub-circuit comprises a second photoelectric sensing element, and the first photoelectric sensing element and the second photoelectric sensing element have same electrical characteristics.

For example, in the photoelectric detection circuit provided in the at least one embodiment of this disclosure, the second detection sub-circuit is blocked to prevent light to be detected from the environment from illuminating the second detection sub-circuit such that the second detection sub-circuit is in a state the fixed illumination intensity.

For example, in the photoelectric detection circuit provided in the at least one embodiment of this disclosure, further comprising a first power end and a second power end, wherein a first end of the first photoelectric sensing element is electrically connected to the first power end, a second end of the second photoelectric sensing element is electrically connected to the second power end, and a second end of the first photoelectric sensing element and a first end of the second photoelectric sensing element are both electrically connected to the first node.

For example, in the photoelectric detection circuit provided in the at least one embodiment of this disclosure, an output potential of the first power end is higher than an output potential of the second power end.

For example, in the photoelectric detection circuit provided in the at least one embodiment of this disclosure, an output potential of the first power end and an output potential of the second power end have opposite polarities and equal magnitudes.

For example, in the photoelectric detection circuit provided in the at least one embodiment of this disclosure, further comprising a third power end and a fourth power end, wherein a control terminal of the first photoelectric sensing element is electrically connected to the third power end; and a control terminal of the second photoelectric sensing element is electrically connected to the fourth power end.

For example, in the photoelectric detection circuit provided in the at least one embodiment of this disclosure, an output potential of the third power end and an output potential of the fourth power end are a same output potential, and a control terminal of the first photoelectric sensing element and a control terminal of the second photoelectric sensing element are under control of the same output potential such that the first photoelectric sensing element and the second photoelectric sensing element stay in off state.

For example, in the photoelectric detection circuit provided in the at least one embodiment of this disclosure, the first photoelectric sensing element comprises a first thin film transistor, and the second photoelectric sensing element comprises a second thin film transistor.

For example, in the photoelectric detection circuit provided in the at least one embodiment of this disclosure, the first thin film transistor comprises a first active layer, the second thin film transistor comprises a second active layer, and the first active layer and the second active layer are formed of a same semiconductor material.

For example, in the photoelectric detection circuit provided in the at least one embodiment of this disclosure, the semiconductor material comprises one or more selected from the group consisting of amorphous silicon, polysilicon or metallic oxide.

For example, in the photoelectric detection circuit provided in the at least one embodiment of this disclosure, the first active layer and the second active layer are formed of a same semiconductor layer.

At least one embodiment of this disclosure provides a photoelectric detection device comprising the photoelectric detection circuit mentioned above.

For example, in the photoelectric detection device provided in the at least one embodiment of this disclosure, further comprising a processing circuitry, wherein the processing circuitry is configured to detect variation of electrical signals output by the signal output lead and perform subsequent processing on the electrical signals.

For example, in the photoelectric detection device provided in the at least one embodiment of this disclosure, further comprising a base substrate, wherein the first detection sub-circuit and the second detection sub-circuit are disposed in a same layer with respect to the base substrate.

For example, in the photoelectric detection device provided in the at least one embodiment of this disclosure, further comprising a light blocking element, wherein the light blocking element overlaps the second detection sub-circuit to block light incident onto the photoelectric detection device from illuminating the second detection sub-circuit, and the first detection sub-circuit is exposed to allow light to be incident onto the photoelectric detection device to illuminate the first detection sub-circuit.

For example, in the photoelectric detection device provided in the at least one embodiment of this disclosure, further comprising a base substrate, wherein the first detection sub-circuit and the second detection sub-circuit are stacked up with respect to the base substrate, and the first detection sub-circuit is disposed on the second detection sub-circuit thereby light incident on the photoelectric detection device is blocked and is not capable of illuminating the second detection sub-circuit.

For example, in the photoelectric detection device provided in the at least one embodiment of this disclosure, further comprising a light blocking element, wherein the light blocking element is disposed between the first detection sub-circuit and the second detection sub-circuit and overlaps the second detection sub-circuit to block light incident onto the photoelectric detection device from illuminating the second detection sub-circuit.

At least one embodiment of this disclosure provides an electronic device comprising the photoelectric detection device mentioned above.

For example, in the electronic device provided in the at least one embodiment of this disclosure, the electronic device is a display panel comprising a display area, wherein the photoelectric detection device is disposed outside of or in the display area.

It is to be understood that the the above summary and the following detailed description of the present disclosure are both illustrative and exemplary and for further explaining the claimed invention.

