TWI703372B - Optical sensor circuit, optical sensor driving method and display panel - Google Patents

Abstract

An optical sensor circuit includes a sensing circuit, a compensation circuit, and a sampling circuit. The sensing circuit is electrically coupled to the compensation circuit and the sampling circuit. The sensing circuit is configured to receive a first controlling signal and output a first sensing signal along a first current path, when the first color light is received. The compensation circuit is configured to receive a low voltage and hold a second current path and a third current path at the low voltage, when the sensing circuit receives the first color light. The sampling circuit is configured to receive the first sensing signal, and output a sampling signal.

Description

The light sensing circuit and the driving method of the light sensing circuit are based on And display panel

This disclosure relates to a light sensing circuit, a driving method of the light sensing circuit, and a display panel, in particular to a light sensing circuit for simultaneously detecting red, green and blue light sources, a driving method of the light sensing circuit, and a display panel.

The light-sensing circuit can be used in an optical touch device. With the characteristic of leakage current generated by the amorphous silicon thin-film transistor element due to illumination, it can be used with a filter element to achieve the effect of sensing light of a specific color. However, if you want to detect different colored lights at the same time, you need to have light sensing circuits for different colored lights, which will increase the complexity of the circuit and affect the aperture ratio of the pixel circuit. Therefore, there is a need for a light sensing circuit that can sense light of different colors at the same time.

The first implementation aspect of this case is to provide a light sensing circuit, which includes a sensing circuit, a compensation circuit, and a sampling circuit. Sensing circuit It is electrically coupled to the compensation circuit and the sampling circuit. The sensing circuit is used to receive the first control signal. When the first color light is received, the sensing circuit is used to output the first sensing signal along the first current path; when the second color light is received, the sensing circuit is used The second sensing signal is output along the second current path; when the third color light is received, the sensing circuit is used to output the third sensing signal along the third current path. The compensation circuit is used to receive a low voltage. When the sensing circuit receives the first color light, the compensation circuit is used to maintain the second current path and the third current path at a low voltage; when the sensing circuit receives the second color light, The compensation circuit is used to maintain the first current path and the third current path at a low voltage; when the sensing circuit receives the third color light, the compensation circuit is used to maintain the first current path and the second current path at a low voltage. The sampling circuit is used for receiving the first sensing signal, the second sensing signal and the third sensing signal, and outputting the sampling signal.

The second implementation aspect of this case is to provide a driving method of a light sensing circuit, which includes: when receiving the first color light, the sensing circuit is used to output the first sensing circuit along the first current path according to the first control signal. The compensation circuit is used to maintain the second current path and the third current path at a low voltage; when receiving the second color light, the sensing circuit uses the first control signal to output the second sense along the second current path The compensation circuit is used to maintain the first current path and the third current path at a low voltage; and when the third color light is received, the sensing circuit is used to output the third current path along the third current path according to the first control signal. The sensing signal and the compensation circuit are used to maintain the first current path and the second current path at a low voltage.

The third implementation aspect of this case is to provide a display panel, Contains: a source drive circuit, a gate drive circuit, a plurality of pixel circuits, a control circuit and a light sensing circuit. The source driving circuit is electrically connected to a plurality of data lines to provide data voltages. The gate drive circuit is electrically connected to a plurality of gate lines to provide gate drive signals. A plurality of pixel circuits are electrically connected to the data line and the gate line for receiving the data voltage. The control circuit is used to provide the first control signal. The light sensing circuit is electrically connected to the control circuit. The light sensing circuit includes a sensing circuit, a compensation circuit and a sampling circuit. The sensing circuit is used for receiving the first control signal and outputting the sensing signal according to the received color light. The compensation circuit is electrically connected to the sensing circuit for receiving a low voltage and maintaining the voltage of the sensing circuit according to the received color light. The sampling circuit is electrically connected with the sensing circuit and the gate driving circuit to receive the sensing signal and output the sampling signal to the source driver.

The light sensing circuit, the driving method of the light sensing circuit, and the display panel of the present invention mainly provide light sensing circuits that can detect different colors of light at the same time, compared to light sensing circuits that require different colors of light for different colors of light. The light sensing circuit of the present disclosure can also use the compensation circuit to compensate the voltage of the sensing circuit under different ambient light intensities to maintain the stability of the circuit, while reducing the number of transistors to increase the aperture ratio of the pixel circuit.

100‧‧‧Display Panel

110‧‧‧Source drive circuit

120‧‧‧Gate drive circuit

130‧‧‧Pixel circuit

130_1~130_6‧‧‧Sub-pixel circuit

140‧‧‧Control circuit

150‧‧‧Light sensing circuit

151‧‧‧Sensing circuit

152‧‧‧Compensation circuit

153‧‧‧Sampling circuit

R, G, B‧‧‧node

DL‧‧‧Data line

GL‧‧‧Gate line

S(n), G(n), G1(n), G2(n), G3(n)‧‧‧Control signal

CSr, CSg, CSb‧‧‧Capacitor

SR, SG, SB‧‧‧Sensing signal

VL‧‧‧Low voltage

VH‧‧‧High voltage

TP1, TP2, TP3, TP4, TP5, TP6‧‧‧Photosensitive element

T1, T2, T3‧‧‧Switch

I1, I2, I3, I4, I5, I6‧‧‧Current path

OUT, OUT1, OUT2, OUT3‧‧‧output terminal

VGL‧‧‧Prohibition level

VGH‧‧‧Enable Level

CFr, CFg, CFb‧‧‧Filter element

X‧‧‧direction

P1, P2, P3‧‧‧Phase

710‧‧‧Display area

720‧‧‧Induction zone

400‧‧‧Drive method of light sensing circuit

S410~S430a, S430b‧‧‧Step

In order to make the above and other objectives, features, advantages and embodiments of the disclosure document more obvious and understandable, the description of the accompanying drawings is as follows: Figure 1 is a circuit block diagram of a display panel according to an embodiment of the disclosure; FIG. 2 is a circuit block diagram of a light sensing circuit according to an embodiment of the present disclosure; FIG. 3A is a circuit diagram of a light sensing circuit according to an embodiment of the present disclosure; FIG. 3B is an implementation according to an embodiment of the present disclosure Fig. 4A is a flowchart of a driving method of a light sensor circuit according to an embodiment of this disclosure; Fig. 4B is a driving method of a light sensor circuit according to an embodiment of this disclosure A flowchart of the method; FIG. 5A is a timing diagram of the operation of the light sensing circuit according to an embodiment of the present disclosure; FIG. 5B is a timing diagram of the operation of the light sensing circuit according to an embodiment of the present disclosure; FIG. 6A FIG. 6B is a schematic diagram of the operation of the light sensing circuit in the sensing stage according to an embodiment of the present disclosure; FIG. 6B is a schematic diagram of the operation of the light sensing circuit in the sensing stage according to an embodiment of the present disclosure; The operation schematic diagram of the light sensing circuit of an embodiment of the present disclosure in the sensing stage; FIG. 7A is a partial schematic diagram of a display panel according to some embodiments of the present application; FIG. 7B is a schematic diagram of a display panel according to some embodiments of the present application A partial schematic diagram of the display panel shown; and FIG. 7C is a partial schematic diagram of a display panel according to some embodiments of the present application.

The embodiments of the present invention will be described below in conjunction with related drawings. In the drawings, the same reference numerals indicate the same or similar elements or method flows.

Please refer to Figure 1. FIG. 1 is a circuit block diagram of a display panel 100 according to an embodiment of the present disclosure. As shown in FIG. 1, the display panel 100 includes a source driving circuit 110, a gate driving circuit 120, a plurality of pixel circuits 130, a control circuit 140 and a light sensing circuit 150. The source driving circuit 110 is electrically connected to a plurality of data lines DL for providing data voltages. The gate driving circuit 120 is electrically connected to a plurality of gate lines GL to provide gate driving signals. The pixel circuit 130 is electrically connected to the data line DL and the gate line GL for receiving the data voltage. The control circuit 140 is used to provide a first control signal.

For the above, please refer to Figure 1 and Figure 2 together. FIG. 2 is a circuit block diagram of the light sensing circuit 150 according to an embodiment of the present disclosure. As shown in FIG. 2, the light sensing circuit 150 includes a sensing circuit 151 for receiving the first control signal S(n) and the low voltage VL, and outputting a sensing signal according to the received color light. The compensation circuit 152 is electrically connected to the sensing circuit 151 for receiving the low voltage VL and maintaining the voltage of the sensing circuit 151 according to the received color light. The sampling circuit 153 is electrically connected to the sensing circuit 151 and the control circuit 140 to receive the sensing signal and output the sampling signal to the control circuit 140.

In summary, in detail, when the first color light is received, the sensing circuit 151 is used to output the first sensing signal SR along the first current path I1, and the compensation circuit 152 is used to use the second current path I2 and the The three current path I3 is maintained at the low voltage VL. When the second color light is received, the sensing circuit 151 is used to output the second sensing signal SG along the second current path I2, and the compensation circuit 152 is used to maintain the first current path I1 and the third current path I3 at a low voltage VL. When the third color light is received, the sensing circuit 151 is used to output a third sensing signal SB along the third current path I3, and the compensation circuit 152 is used to maintain the first current path I1 and the second current path I2 at a low voltage VL. The sampling circuit 153 is used for receiving the first sensing signal SR, the second sensing signal SG, and the third sensing signal SB, and outputting the sampling signal.

With further reference to FIG. 3A, FIG. 3A is a circuit diagram of the light sensing circuit 150 according to an embodiment of the present disclosure. As shown in FIG. 3A, the light sensing circuit 150 includes a sensing circuit 151, a compensation circuit 152, and a sampling circuit 153. The compensation circuit 152 includes a photosensitive element TP1, a photosensitive element TP2, and a photosensitive element TP3. The first end of the photosensitive element TP1 is electrically connected to the control end of the photosensitive element TP3, and the second end of the photosensitive element TP1 is used for receiving the low voltage VL. The first end of the photosensitive element TP2 is electrically connected to the control end of the photosensitive element TP1, and the second end of the photosensitive element TP2 is used to receive the low voltage VL. The first end of the photosensitive element TP3 is electrically connected to the control end of the photosensitive element TP2, and the second end of the photosensitive element TP3 is used to receive the low voltage VL.

In view of the above, as shown in FIG. 3A, the sensing circuit 151 includes a photosensitive element TP4, a photosensitive element TP5, and a photosensitive element TP6. The first end of the photosensitive element TP4 is electrically connected to the node R, and the second end of the photosensitive element TP4 is used for To receive the first control signal S(n), the control end of the photosensitive element TP4 is electrically connected to the control end of the photosensitive element TP1 and the first end of the photosensitive element TP2. The first end of the photosensitive element TP5 is electrically connected to the node G, the second end of the photosensitive element TP5 is used to receive the first control signal S(n), the control end of the photosensitive element TP5 is electrically connected to the control end of the photosensitive element TP2 and The first end of the photosensitive element TP3. The first end of the photosensitive element TP6 is electrically connected to node B, the second end of the photosensitive element TP6 is used to receive the first control signal S(n), the control end of the photosensitive element TP6 is electrically connected to the control end of the photosensitive element TP3 and The first end of the photosensitive element TP1.

In view of the above, the sensing circuit 151 further includes a capacitor CSr, a capacitor CSg, and a capacitor CSb. The first terminal of the capacitor CSr is electrically connected to the node R, and the second terminal of the capacitor CSr is used to receive the low voltage VL. The first terminal of the capacitor CSg is electrically connected to the node G, and the second terminal of the capacitor CSg is used to receive the low voltage VL. The first terminal of the capacitor CSb is electrically connected to the node B, and the second terminal of the capacitor CSb is used to receive the low voltage VL.

In view of the above, the sampling circuit 153 includes a switch T1, a switch T2, and a switch T3. The first terminal of the switch T1 is electrically connected to the node R, the second terminal of the switch T1 is electrically connected to the output terminal OUT1, and the control terminal of the switch T1 is used for receiving the second control signal G(n). The first terminal of the switch T2 is electrically connected to the node G, the second terminal of the switch T2 is electrically connected to the output terminal OUT2, and the control terminal of the switch T2 is used for receiving the second control signal G(n). The first terminal of the switch T3 is electrically connected to the node B, the second terminal of the switch T3 is electrically connected to the output terminal OUT3, and the control terminal of the switch T3 is used to receive the second control signal G(n). Among them, the output terminal OUT1, output terminal OUT2 and output terminal OUT3 are further connected to the control Control circuit 140 (not shown in Figure 3A).

In another embodiment, the output terminal OUT1, the output terminal OUT2, and the output terminal OUT3 can be connected to a readout circuit to read the sensing result of the light sensing circuit 150.

In view of the above, the photosensitive element TP1 and the photosensitive element TP5 are covered by the filter element CFg. The filter element CFg is used to pass the first color light. For example, the first color light can be implemented as red light with a wavelength range of about approx. 620~750 nanometers (nm). With this arrangement, red light is easier to pass through the filter element CFr than other colors outside this wavelength range.

In view of the above, the photosensitive element TP2 and the photosensitive element TP6 are covered by the filter element CFb. The filter element CFb is used to pass the second color light. For example, the second color light can be implemented as green light with a wavelength range of about 495~ 570 nanometers (nm). With this arrangement, green light can pass through the filter element CFg more easily than other colors outside this wavelength range.

In view of the above, the photosensitive element TP3 and the photosensitive element TP4 are covered by the filter element CFr. The filter element CFr is used to pass the third color light. For example, the third color light can be implemented as blue light with a wavelength range of about 450~ 495 nanometers (nm). With this arrangement, blue light can pass through the filter element CFb more easily than other colors outside this wavelength range.

In each embodiment, the related settings of the first color light to the third color light can be changed according to actual applications, that is, the color distribution mode of the first color light to the third color light is not limited to green, blue, and red. Corresponding to the color distribution mode of the first color light to the third color light, the implementation of the filter element CFg, the filter element CFb, and the filter element CFr will also be adjusted accordingly.

In another embodiment, please refer to FIG. 3B. FIG. 3B is a circuit diagram of a light sensing circuit 150 according to an embodiment of the present disclosure. The difference between the embodiment shown in FIG. 3B and the embodiment shown in FIG. 3A is that the second end of the switch T1, the second end of the switch T2, and the second end of the switch T3 of the sampling circuit 153 are electrically connected to The output terminal OUT is further connected to the control circuit 140 (not shown in Figure 3B).

In another embodiment, the output terminal OUT can be connected to a readout circuit to read the sensing result of the light sensing circuit 150.

In view of the above, in this embodiment, the light sensing circuit 150 is configured as a rechargeable light sensing circuit, so the voltage can be set to a low voltage VL. In another embodiment, if the light sensing circuit 150 is configured as a discharge type light sensing circuit, the low voltage VL can be changed to a high voltage.

In one embodiment, the photosensitive elements Tp1 to Tp6 and the switches T1 to T3 can be any of bipolar transistors (BJT), field effect transistors (FET) and/or thin film transistors (Thin-Film Transistor, TFT) Implement. In this embodiment. The photosensitive elements Tp1 to Tp6 are illustrated by taking N-type TFTs as an example, but this case is not limited to this. According to different applications, each photosensitive element in this case is implemented with various types of transistors. When the control terminal (for example, the gate) of each transistor receives a non-conducting signal (for example, a low voltage VL), the voltage difference between the control terminal and the second terminal (for example, the source) is lower than the threshold voltage of the transistor ( Threshold voltage), so that the transistor operates in the cutoff region, or subthreshold region. Under this operating condition, different illumination intensity and input signal size will affect the leakage current of the transistor (or called Is the sub-critical current (subthreshold leakage)).

Please refer to FIG. 4A and FIG. 5A. FIG. 4A is a flowchart of a method 400 for driving a light sensor circuit according to an embodiment of the present disclosure, and FIG. 5A is a light sensor according to an embodiment of the present disclosure. The operation timing diagram of the circuit 150. As shown in FIG. 4A, the driving method 400 of the light sensing circuit first executes step S410. In the initial stage P1, the first control signal S(n) is at the low voltage VL to change the voltage of the node R and the node G The voltage of, and the voltage of node B are reset to the low voltage VL, and the second control signal G(n) is at the disable level VGL, so that the sampling circuit 153 is turned off. In one embodiment, since the sampling circuit 153 is in the off state, the capacitor Csr, the capacitor Csg, and the capacitor Csb are discharged, and the voltage of the node R, the voltage of the node G, and the voltage of the node B are reset to the low voltage VL. At the same time, since the first control signal S(n) is at the low voltage VL, the photosensitive elements TP4 to TP6 are also reset to the low voltage VL.

Next, the driving method 400 of the light sensing circuit executes step S420. In the sensing phase P2, the first control signal S(n) is at the high voltage VH, and when the light sensing element TP4 receives the first color light, the light sensing element TP4 is turned on , The high voltage VH raises the voltage of the node R to a high voltage level along the first current path I1; when the photosensitive element TP5 receives the second color light, the photosensitive element TP5 is turned on, and the high voltage VH increases the voltage along the second current path I2 The voltage of the node G rises to a high voltage level; when the photosensitive element TP6 receives the third color light, the photosensitive element TP6 is turned on, and the high voltage VH increases the voltage of the node B to the high voltage level along the third current path I3.

In view of the above, please also refer to FIG. 6A. FIG. 6A shows the operation of the light sensing circuit 150 in the sensing stage P2 according to an embodiment of the present disclosure. Make a schematic diagram. In this embodiment, the circuit shown in FIG. 3A is taken as an example to illustrate the operation mode of the sensing phase P2. The circuit shown in FIG. 3A also has the same operation mode, which will not be repeated here. As shown in Figure 6A, if the first color light (for example, red light) is irradiated to the light sensing circuit 150 at this time, the photosensitive element TP3 and the photosensitive element TP4 will be excited by the red light to generate current, as shown by the dotted line in Figure 6A As shown by the arrow, after the photosensitive element TP4 is turned on, the high voltage VH charges the node R along the first current path I1, and the photosensitive element TP2 will continue to pull down the potential of the control terminal of the photosensitive element TP1 to the low voltage VL, and the photosensitive element TP1 will not It is turned on so that the current on the first current path I1 will not be dispersed.

During this period of time, the photosensitive element TP1, photosensitive element TP2, photosensitive element TP5, and photosensitive element TP6 will also generate current due to the light, but at this time, the current generated by the first color light is less than that of the photosensitive element TP3 and photosensitive element TP4. Due to the compensation of the photosensitive element TP3 and the photosensitive element TP1 in the compensation circuit 152, the current generated by the photosensitive element TP5 and the photosensitive element TP6 will continue to follow the fourth current path I4 and the fifth current path I5, respectively, Pull down to the low voltage VL to maintain the voltages of the node G and the node B at the low voltage VL.

In view of the above, please also refer to FIG. 6B. FIG. 6B is a schematic diagram of the operation of the light sensing circuit 150 in the sensing stage P2 according to an embodiment of the present disclosure. As shown in FIG. 6B, if the second color light (for example, green light) is irradiated to the light sensing circuit 150 at this time, the photosensitive element TP1 and the photosensitive element TP5 will be excited by the green light to generate current. In this embodiment, the operation of the photosensitive element TP1 and the photosensitive element TP5 being excited by the green light is similar to the operation of the aforementioned photosensitive element TP3 and the photosensitive element TP4 being excited by the red light. As shown by the dotted arrow in Figure 6B, After the photosensitive element TP5 is turned on, the high voltage VH charges the node G along the second current path I2. At the same time, the photosensitive element TP3 will continue to pull down the potential of the control terminal of the photosensitive element TP2 to the low voltage VL, and the photosensitive element TP2 is not turned on, making the first The current on the second current path I2 will not be dispersed.

During this time period, due to the compensation of the photosensitive element TP2 and the photosensitive element TP3 in the compensation circuit 152, the current generated by the photosensitive element TP4 and the photosensitive element TP6 will continue to follow the sixth current path I6 and the fifth current path I5, respectively. Pull down to the low voltage VL to maintain the voltages of the node R and the node B at the low voltage VL.

In view of the above, please also refer to FIG. 6C. FIG. 6C is a schematic diagram of the operation of the light sensing circuit 150 in the sensing phase P2 according to an embodiment of the present disclosure. As shown in FIG. 6C, if the third color light (for example, blue light) is irradiated to the light sensing circuit 150 at this time, the photosensitive element TP2 and the photosensitive element TP6 will be excited by the blue light to generate current. In this embodiment, the operation of the photosensitive element TP2 and the photosensitive element TP6 being excited by blue light is similar to the operation of the aforementioned light element TP3 and the photosensitive element TP4 being excited by red light. As shown by the dotted arrow in Figure 6C, after the photosensitive element TP6 is turned on, the high voltage VH charges the node B along the third current path I3, and the photosensitive element TP1 will continue to pull down the potential of the control terminal of the photosensitive element TP3 to a low voltage VL, the photosensitive element TP3 is not turned on, so that the current on the third current path I3 will not be dispersed.

During this period of time, due to the compensation of the photosensitive element TP1 and the photosensitive element TP3 in the compensation circuit 152, the current generated by the photosensitive element TP4 and the photosensitive element TP5 will continue to follow the sixth current path I6 and the fourth current path I4, respectively. Pull down to the low voltage VL to maintain the voltage of node R and node G Keep at low voltage VL.

Next, the driving method 400 of the light sensing circuit executes step S430a. In the sampling phase P3, the second control signal G(n) is at the enable level VGH, so that the switches T1, T2, and T3 are turned on for The voltage of the node R, the voltage of the node G, and the voltage of the node B are respectively transmitted to the output terminal OUT1, the output terminal OUT2, and the output terminal OUT3 as sampling signals. In one embodiment, as shown in FIG. 5, after the second control signal G(n) is switched to the enable level VGH, the switch T1, the switch T2, and the switch T3 can respectively change the voltage of the node R and the voltage of the node G And the voltage of the node B is output to the output terminal OUT1, the output terminal OUT2, and the output terminal OUT3.

In another embodiment, please refer to FIG. 3B, FIG. 4B, and FIG. 5B together. FIG. 4B is a flowchart of a driving method 400 of a light sensing circuit according to an embodiment of the present disclosure, and FIG. 5B The figure is a timing diagram of the operation of the light sensing circuit 150 according to an embodiment of the present disclosure. The difference between the embodiment shown in FIG. 4B and the embodiment shown in FIG. 4A is that the operation of the sampling stage P3 is different. As shown in FIG. 4B, the driving method 400 of the light sensing circuit executes step S430b. In the sampling period P3, the second control signal G1(n) is switched to the enable level VGH during the first sampling period, so that the switch T1 is The on state is used to transmit the voltage of the node R as a sampling signal to the output terminal OUT; the third control signal G2(n) is switched to the enable level VGH during the second sampling period, so that the switch T2 is in the on state for The voltage of node G is sent to the output terminal OUT as a sampling signal; the fourth control signal G3(n) is switched to the enable level VGH during the third sampling period, so that the switch T3 is turned on to use the voltage of node B as The sampling signal is sent to the output terminal OUT.

In one embodiment, as shown in FIG. 5B, after the second control signal G1(n) is switched to the enable level VGH, the switch T1 is turned on, the switch T2 and the switch T3 are in the off state, and the switch T1 can connect the node R The voltage is output to the output terminal OUT. After the third control signal G2(n) is switched to the enable level VGH, the switch T2 is turned on, the switch T1 and the switch T3 are turned off, and the switch T2 can output the voltage of the node G to the output terminal OUT. After the fourth control signal G3(n) is switched to the enable level VGH, the switch T3 is turned on, the switch T1 and the switch T2 are turned off, and the switch T3 can output the voltage of the node B to the output terminal OUT. It should be noted that the first sampling period, the second sampling period, and the third sampling period do not overlap with each other.

In one embodiment, please refer to FIG. 7A, which is a partial schematic diagram of the display panel 100 according to some embodiments of the present application. For ease of understanding, please refer to FIGS. 3A and 3B together, and similar elements in FIG. 7A and the above drawings will be designated with the same reference numerals. In one embodiment, the display panel 100 includes a plurality of pixel circuits 130 and a plurality of light sensing circuits 150, and the pixel circuit 130 includes a plurality of sub-pixel circuits. Each sub-pixel circuit is covered by a corresponding filter element. For example, along the direction X, the filter element CFr, the filter element CFg, and the filter element CFb are sequentially and repeatedly arranged.

In view of the above, as shown in Figure 7A, taking a 6*3 (and 6 columns and 3 columns) sub-pixel circuit as an example, the sensing circuit 151 and the compensation circuit 152 are arranged on one side of the pixel circuit 130, and the light-shielding element The blocking matrix (BM) is provided with a light-transmitting area corresponding to the sensing circuit 151 and the compensation circuit 152, so that the photosensitive elements Tp1 to Tp6 in the sensing circuit 151 and the compensation circuit 152 Ambient light can be sensed. The light sensing circuits 150 are arranged at intervals between the pixel circuits 130, and the distance between the light sensing circuits 150 is about 1 to 3 mm apart. In one embodiment, the sampling circuit 153 is covered by a shading element (not shown in Figure 7A). In view of the foregoing, the arrangement of the pixel circuit 130 and the light sensing circuit 150 shown in FIG. 7A can be combined with the circuit connection methods shown in FIGS. 3A and 3B, and will not be repeated here.

In another embodiment, please refer to FIG. 7B. FIG. 7B is a partial schematic diagram of the display panel 100 according to some embodiments of the present application. For ease of understanding, please refer to FIGS. 3A and 3B together, and similar elements in FIG. 7B and the above drawings will be designated with the same reference numerals. In one embodiment, the display panel 100 includes a plurality of pixel circuits 130. The pixel circuit 130 includes a plurality of sub-pixel circuits. The sub-pixel circuits have a display area 710, and a part of the sub-pixel circuits 130 are more Contains the sensing area 720. A display circuit is provided in the display area 710 for displaying an image. The aforementioned light sensing circuit 150 is disposed in the sensing area 720, which is used for sensing external ambient light.

In one embodiment, the plurality of pixel circuits 130 in the display panel 100 are arranged in an array. Each sub-pixel circuit is covered by a corresponding filter element. For example, along the direction X, the filter element CFr, the filter element CFg, and the filter element CFb are sequentially and repeatedly arranged. Each photosensitive element in the light sensing circuit 150 can be implemented by a plurality of transistors connected in parallel, and the plurality of transistors can be respectively arranged in a plurality of pixel circuits 130 and connected in parallel with each other through internal connections (not shown) , To equivalently form the light sensing circuit 150 discussed above.

In view of the above, as shown in Figure 7B, taking the 6*3 (and 6 columns and 3 columns) sub-pixel circuit as an example, the sensing area 720 of the sub-pixel circuit 130_1 is provided with the photosensitive element Tp4, and the sub-pixel circuit 130_2 The sensing area 720 is provided with a photosensitive element Tp5, the sensing area 720 of the sub-pixel circuit 130_3 is provided with a photosensitive element Tp2, the sensing area 720 of the sub-pixel circuit 130_4 is provided with a photosensitive element Tp3, and the sub-pixel circuit 130_5 is provided with a sensing area 720 The photosensitive element Tp1 and the sensing area 720 of the sub-pixel circuit 130_6 are provided with a photosensitive element Tp6. The light sensing circuits 150 are arranged at intervals between the pixel circuits 130, and the distance between the light sensing circuits 150 is about 1 to 3 mm apart. In one embodiment, the sampling circuit 153 is covered by a shading element (not shown in Figure 7B). In view of the foregoing, the arrangement of the pixel circuit 130 and the light sensing circuit 150 shown in FIG. 7B can be matched with the circuit connection method shown in FIG. 3B, which will not be repeated here.

In another embodiment, please refer to FIG. 7C. FIG. 7C is a partial schematic diagram of the display panel 100 according to some embodiments of the present application. For ease of understanding, please refer to FIGS. 3A and 3B together, and similar elements in FIG. 7C and the above drawings will be designated with the same reference numerals. The difference between the embodiment shown in FIG. 7C and the embodiment shown in FIG. 7B is that the arrangement of the display area 710 and the sensing area 720 in the sub-pixel circuit is different, which will not be repeated here.

To sum up, the light sensing circuit, the driving method of the light sensing circuit, and the display panel of the present disclosure mainly propose light sensing circuits that can detect different colors of light at the same time. Compared with different colors of light, different colors of light are required. As far as the sensing circuit is concerned, the light sensing circuit of the present disclosure can be in different rings Under ambient light intensity, the compensation circuit can also be used to compensate the voltage of the sensing circuit to maintain the stability of the circuit, while reducing the number of transistors to increase the aperture ratio of the pixel circuit.

Certain words are used in the specification and the scope of the patent application to refer to specific elements. However, those with ordinary knowledge in the technical field should understand that the same element may be called by different terms. The specification and the scope of the patent application do not use the difference in names as a way of distinguishing elements, but the difference in function of the elements as the basis for distinguishing. The "including" mentioned in the specification and the scope of the patent application is an open term, so it should be interpreted as "including but not limited to". In addition, "coupling" here includes any direct and indirect connection means. Therefore, if the text describes that the first element is coupled to the second element, it means that the first element can be directly connected to the second element through electrical connection, wireless transmission, optical transmission, or other signal connection methods, or through other elements or connections. The means is indirectly connected to the second element electrically or signally.

In addition, unless otherwise specified in the specification, any term in the singular case also includes the meaning of the plural case.

The above are only preferred embodiments of the present invention, and all equivalent changes and modifications made in accordance with the claims of the present invention should fall within the scope of the present invention.

100‧‧‧Display Panel

110‧‧‧Source drive circuit

120‧‧‧Gate drive circuit

130‧‧‧Pixel circuit

140‧‧‧Control circuit

150‧‧‧Light sensing circuit

DL‧‧‧Data line

GL‧‧‧Gate line

Claims (16)

A light sensing circuit, comprising: a sensing circuit for receiving a first control signal, when receiving a first color light, the sensing circuit for outputting a first sensor along a first current path When a second color light is received, the sensing circuit is used to output a second sensing signal along a second current path; when a third color light is received, the sensing circuit is used to follow A third current path outputs a third sensing signal; a compensation circuit is electrically connected to the sensing circuit to receive a low voltage. When the sensing circuit receives the first color light, the compensation circuit Used to maintain the second current path and the third current path at the low voltage; when the sensing circuit receives the second color light, the compensation circuit is used to maintain the first current path and the third current path Maintained at the low voltage; when the sensing circuit receives the third color light, the compensation circuit is used to maintain the first current path and the second current path at the low voltage; and a sampling circuit, and the sensing circuit The sensing circuit is electrically connected to receive the first sensing signal, the second sensing signal, and the third sensing signal, and output a sampling signal. The light sensing circuit according to claim 1, wherein the compensation circuit further comprises: a first photosensitive element having a first terminal, a second terminal and a first control terminal, and the second terminal is used for receiving the low voltage; A second photosensitive element having a third terminal, a fourth terminal and a second control terminal, the third terminal is electrically connected to the first control terminal, and the fourth terminal is used for receiving the low voltage; and a The third photosensitive element has a fifth terminal, a sixth terminal, and a third control terminal. The fifth terminal is electrically connected to the second control terminal. The sixth terminal is used to receive the low voltage. The control terminal is electrically connected to the first terminal. The light sensing circuit according to claim 2, wherein the sensing circuit further comprises: a fourth photosensitive element having a seventh terminal, an eighth terminal and a fourth control terminal, and the seventh terminal is electrically connected To a first node, the eighth terminal is used to receive the first control signal, the fourth control terminal is electrically connected to the first control terminal; a fifth photosensitive element has a ninth terminal and a tenth terminal And a fifth control terminal, the ninth terminal is electrically connected to a second node, the tenth terminal is used for receiving the first control signal, the fifth control terminal is electrically connected to the second control terminal; and a The sixth photosensitive element has an eleventh end, a twelfth end, and a sixth control end, the eleventh end is electrically connected to a third node, and the twelfth end is used to receive the first control Signal, the sixth control terminal is electrically connected to the third control terminal. The light sensing circuit according to claim 3, wherein the sensing circuit further comprises: A first capacitor has a first terminal and a second terminal, the first terminal is electrically connected to the first node, and the second terminal is used to receive the low voltage; a second capacitor has a third terminal And a fourth terminal, the third terminal is electrically connected to the second node, and the fourth terminal is used to receive the low voltage; and a first capacitor having a fifth terminal and a sixth terminal, the fifth terminal The terminal is electrically connected to the third node, and the sixth terminal is used for receiving the low voltage. The light sensing circuit according to claim 3, wherein the sampling circuit further comprises: a first switch having a first terminal, a second terminal and a first control terminal, the first terminal is electrically connected to the The first node, the second terminal is electrically connected to an output terminal, the first control terminal is used to receive a second control signal; a second switch has a third terminal, a fourth terminal and a second control Terminal, the third terminal is electrically connected to the second node, the fourth terminal is electrically connected to the output terminal, the second control terminal is used for receiving a third control signal; and a third switch having a first Five terminals, a sixth terminal, and a third control terminal. The fifth terminal is electrically connected to the third node, the sixth terminal is electrically connected to the output terminal, and the third control terminal is used to receive a fourth node. Control signal. The light sensing circuit according to claim 3, wherein the sampling circuit further comprises: a first switch having a first terminal, a second terminal and a first control terminal, the first terminal is electrically connected to the The first node, the second terminal is electrically connected Connected to a first output terminal, the first control terminal is used to receive a second control signal; a second switch has a third terminal, a fourth terminal and a second control terminal, the third terminal is electrical Connected to the second node, the fourth terminal is electrically connected to a second output terminal, the second control terminal is used to receive the second control signal; and a third switch having a fifth terminal and a sixth terminal Terminal and a third control terminal, the fifth terminal is electrically connected to the third node, the sixth terminal is electrically connected to a third output terminal, and the third control terminal is used for receiving the second control signal. The light sensing circuit according to claim 3, wherein in the initial stage, the first control signal is at the low voltage for the voltage of the first node, the voltage of the second node, and the voltage of the third node The voltage is reset to the low voltage, and the second control signal is at a disable level, so that the sampling circuit is turned off. The light sensing circuit according to claim 3, wherein in the sensing phase, the first control signal is at a high voltage, and when the fourth photosensitive element receives the first color light, the fourth photosensitive element is turned on , The high voltage raises the voltage of the first node to a high voltage level along the first current path; when the fifth photosensitive element receives the second color light, the fifth photosensitive element is turned on, and the high voltage is along The second current path raises the voltage of the second node to a high voltage level; when the sixth photosensitive element receives the first In the case of tricolor light, the sixth photosensitive element is turned on, and the high voltage increases the voltage of the third node to a high voltage level along the third current path. The light sensing circuit according to claim 5, wherein in the sampling phase, the second control signal is switched to a uniform energy level in a first period of time, so that the first switch is turned on for the first The voltage of the node is sent to an output terminal as the sampling signal; the third control signal is switched to the enable level in a second period of time, so that the second switch is turned on, and the voltage of the second node is used as The sampling signal is transmitted to the output terminal; the fourth control signal is switched to the enable level in a third period of time, so that the third switch is turned on, and is used to transmit the voltage of the third node as the sampling signal To this output. The light sensing circuit according to claim 9, wherein the first period, the second period, and the third period do not overlap with each other. The light sensing circuit according to claim 6, wherein in the sampling phase, the second control signal is at a uniform energy level, so that the first switch, the second switch, and the third switch are turned on for The voltage of the first node, the voltage of the second node and the voltage of the third node are respectively transmitted as the sampling signal to the first output terminal, the second output terminal and the third output terminal. A driving method of a light sensing circuit includes: When receiving a first color light, a sensing circuit is used to output a first sensing signal along a first current path according to a first control signal, and a compensation circuit is used to combine a second current path and a The third current path is maintained at a low voltage; when a second color light is received, the sensing circuit outputs a second sensing signal along the second current path according to the first control signal, and the compensation circuit uses To maintain the first current path and the third current path at the low voltage; and when receiving a third color light, the sensing circuit is configured to output a third current path along a third current path according to the first control signal The third sensing signal is used for maintaining the first current path and the second current path at the low voltage by the compensation circuit. The driving method of the light sensing circuit according to claim 12, further comprising: in the initial stage, the first control signal is at the low voltage for changing the voltage of a first node, the voltage of a second node, and The voltage of a third node is reset to the low voltage, and a second control signal is at a disable level, so that a sampling circuit is turned off. The driving method of the light sensing circuit according to claim 13, wherein in the sensing phase, the first control signal is at a high voltage, and when a fourth photosensitive element receives the first color light, the fourth The photosensitive element is turned on, and the high voltage increases the voltage of the first node along the first current path. Raise to a high voltage level; when a fifth photosensitive element receives the second color light, the fifth photosensitive element is turned on, and the high voltage raises the voltage of the second node to a high voltage level along the second current path; When a sixth photosensitive element receives the third color light, the sixth photosensitive element is turned on, and the high voltage increases the voltage of the third node to a high voltage level along the third current path. The driving method of the light sensing circuit according to claim 13, further comprising: in the sampling phase, the second control signal is switched to a uniform energy level, so that the sampling circuit is turned on, according to the first sensing signal, the The second sensing signal and the third sensing signal output a sampling signal. A display panel includes: a source drive circuit electrically connected to a plurality of data lines to provide a data voltage; a gate drive circuit electrically connected to a plurality of gate lines to provide a gate Driving signal; a plurality of pixel circuits electrically connected to the data lines and the gate lines for receiving the data voltage; a control circuit for providing a first control signal; and a light sensing circuit , Electrically connected to the control circuit, and the light sensing circuit includes: a sensing circuit for receiving the first control signal and The received color light outputs a sensing signal; a compensation circuit is electrically connected to the sensing circuit for receiving a low voltage and maintaining the voltage of the sensing circuit according to the received color light; and a sampling circuit, It is electrically connected with the sensing circuit and the control circuit for receiving the sensing signal and outputting a sampling signal to the control circuit.

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