Optical sensing circuit and sensing key

Abstract

The photosensitive circuit and sensing button provided in this application include a light emitting tube, a main light receiving tube, and at least one auxiliary light receiving tube. The main receiving tube and all auxiliary receiving tubes can receive light emitted from the light emitting tube. The main receiving tube and the auxiliary receiving tubes can output corresponding sensing signals based on changes in the received light, thereby increasing the stability of the photosensitive circuit and the sensing button.

Description

Technical Field

[0001] This application relates to the field of light sensing detection, and in particular to a light sensing circuit and a sensing button. Background Technology

[0002] With social development and the improvement of people's living standards, there are more and more human-computer interaction scenarios, and light-sensing automatic control is becoming more and more common. For example, elevators can be equipped with non-contact sensor buttons. These sensor buttons can be automatically opened when a finger is detected within a limited range by light sensing, saving the corresponding cumbersome operation and making people's lives more convenient.

[0003] Therefore, during the process of conceiving this application, the inventor discovered that the existing technology has at least the following problems: under actual working conditions, if the button panel of the sensing button is contaminated with water or other foreign matter, it will interfere with the light sensing button or even cause false triggering. As a result, the ability to identify the sensed object is not high and the accuracy is poor.

[0004] The preceding description is intended to provide general background information and does not necessarily constitute prior art. Utility Model Content

[0005] In view of the above problems, the purpose of this application is to provide a light-sensing circuit and a sensor button. By designing the light-sensing circuit and optimizing the layout of the circuit components, the sensor button can avoid false triggering when it is contaminated with water or other foreign objects, thereby improving the sensor button's ability to recognize human interaction.

[0006] This application provides a light sensing circuit, which includes: a light emitting tube, a main light receiving tube, and at least one auxiliary light receiving tube;

[0007] The anode of the light-emitting tube is connected to the output terminal of the power supply, and the cathode of the light-emitting tube is grounded;

[0008] The input terminals of both the main optical receiver and the auxiliary optical receiver are connected to the power supply. The output terminals of both the main optical receiver and the auxiliary optical receiver are connected to a circuit node, and the circuit node is connected to the ground wire. The main optical receiver and the auxiliary optical receiver are used to receive the light emitted by the optical transmitter and output the corresponding sensing signal through the output terminal.

[0009] Optionally, the light-sensing circuit further includes: a control module and a first switching element;

[0010] The first switching element is connected in series between the cathode of the light emitting tube and the ground wire, and the control terminal of the first switching element is connected to the first output terminal of the control module.

[0011] Optionally, the light-sensing circuit further includes: a control module and a second switching element;

[0012] The second switch is connected in series in the wiring between the circuit node and the ground wire, and the control terminal of the second switch is connected to the second output terminal of the control module.

[0013] Optionally, the photosensing circuit further includes: a control module, a first pull-down resistor, and a second pull-down resistor;

[0014] One end of the first pull-down resistor is connected to the detection terminal of the control module, and the other end is connected to the ground wire;

[0015] The second pull-down resistor is connected at one end to the circuit node and at the other end to the ground.

[0016] Optionally, the photosensitive circuit may further include a first sampling resistor and / or a second sampling resistor;

[0017] The first sampling resistor is located between the output terminal of the main optical receiver tube and the circuit node;

[0018] The second sampling resistor is located between the output terminal of the auxiliary optical receiver tube and the circuit node;

[0019] The first input terminal of the control module is connected to the output terminal of the main optical receiver tube, and can be used to detect the sensing signal output by the main optical receiver tube.

[0020] The second input terminal of the control module is connected to the output terminal of the auxiliary optical receiver tube, and can be used to detect the sensing signal output by the auxiliary optical receiver tube.

[0021] This application also provides a sensor button, including the aforementioned light-sensitive circuit.

[0022] Optionally, the touch-sensitive button may also include a button panel and a circuit board;

[0023] The circuit board is equipped with a light-sensing circuit. The circuit board is parallel to the button panel. On the circuit board, the button panel is located in the projection area of ​​the circuit board. The light-sensing circuit includes a light-emitting tube, a main light-receiving tube, and all auxiliary light-receiving tubes.

[0024] Optionally, on the circuit board, the light emitting tube and the main light receiving tube are arranged horizontally; and / or one auxiliary light receiving tube and the light emitting tube are arranged vertically, and multiple auxiliary light receiving tubes are arranged horizontally.

[0025] Optionally, the distance between the main optical receiver and the optical emitter is less than the distance between the main optical receiver and any one of the auxiliary optical receivers.

[0026] Optionally, the diameter of the sensing panel is in the range of 12mm to 30mm.

[0027] The photosensitive circuit and sensing button provided in this application include a light emitting tube, a main light receiving tube, and at least one auxiliary light receiving tube. The main receiving tube and all auxiliary receiving tubes can receive light emitted from the light emitting tube. The main receiving tube and the auxiliary receiving tubes can output corresponding sensing signals based on changes in the received light, thereby increasing the stability of the photosensitive circuit and the sensing button. Attached Figure Description

[0028] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the circuit structure of the first embodiment of the photosensitive circuit of this application.

[0030] Figure 2 This is a schematic diagram of the circuit structure of the second embodiment of the photosensitive circuit of this application.

[0031] Figure 3 This is a schematic diagram of the structure of a sensor button according to an embodiment of this application. Detailed Implementation

[0032] The foregoing and other technical contents, features, and effects of this application will be clearly presented in the following detailed description of the preferred embodiments with reference to the accompanying drawings. Through the description of the specific embodiments, a more in-depth and concrete understanding can be gained of the technical means and effects adopted by this application to achieve its intended purpose. However, the accompanying drawings are for reference and illustration only and are not intended to limit this application; some well-known parts may not be shown. In the various drawings, the same elements are represented by similar reference numerals. For clarity, the various parts in the drawings are not necessarily drawn strictly to scale.

[0033] It is important to understand that the terms "first," "second," "third," "fourth," etc., are used merely to distinguish elements or circuits with similar properties, and do not indicate or imply relative importance or a specific order. The terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, which includes not only the listed elements but also other elements not expressly listed.

[0034] The technical solutions of this application will be described in detail below with reference to specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. In the description of this application, unless otherwise expressly specified and limited, the terms should be broadly understood within the art. The embodiments of this application will now be described with reference to the accompanying drawings.

[0035] Figure 1 This is a schematic diagram of the circuit structure of the first embodiment of the photosensitive circuit of this application. Figure 1 As shown, the photosensitive circuit provided in this application includes: a light emitting tube IR, a main light receiving tube PT1, and at least one auxiliary light receiving tube (only one PT2 is shown in the figure, but this application is not limited thereto). The anode of the light emitting tube IR is connected to the power supply, and the cathode of the light emitting tube IR is connected to the ground. The input terminals of the main light receiving tube PT1 and the auxiliary light receiving tube PT2 are both connected to the power supply, and the output terminals of the main light receiving tube PT1 and the auxiliary light receiving tube PT2 are both connected to a circuit node A, and the circuit node A is connected to the ground. The main light receiving tube PT1 and the auxiliary light receiving tube PT2 are used to receive the light emitted by the light emitting tube IR and output the corresponding sensing signal through the output terminal.

[0036] In one embodiment, the photosensitive circuit of this application further includes: a current-limiting resistor R, a first switch Q1, a second switch Q2, a first sampling resistor R1, and a second sampling resistor R2 with the same number as the auxiliary photodetectors; wherein, the current-limiting resistor R and the first switch Q1 are connected in series between the cathode of the photodetector IR and the ground wire, the cathode of the photodetector IR is connected to the current-limiting resistor R, and the other end of the current-limiting resistor R is grounded through the first switch Q1. The current-limiting resistor is used to prevent the photodetector IR from burning out due to excessive current.

[0037] The first sampling resistor R1 is connected in series between the output terminal of the main optical receiver PT1 and the circuit node A, the second sampling resistor R2 is connected in series between the output terminal of the auxiliary optical receiver PT2 and the circuit node A (only one auxiliary optical receiver PT2 and the second sampling resistor R2 are shown in the figure, but this application is not limited thereto), and the second switch Q2 is connected in series between the circuit node A and the ground wire.

[0038] In one embodiment, the photosensitive circuit further includes a control module (not shown). The first input terminal In1 of the control module is connected to the common terminal of the main photodetector PT1 and the first sampling resistor R1. The first input terminal In1 can acquire the sensing signal output by the main photodetector PT1. The second input terminal In2 of the control module is connected to the common terminal of the auxiliary photodetector PT2 and the second sampling resistor R2. The second input terminal In2 can acquire the sensing signal output by the auxiliary photodetector PT2. A gap is provided between the main photodetector PT1 and all the auxiliary photodetectors PT2 on the circuit board of the sensing button, preventing foreign objects such as water from synchronously interfering with the main photodetector PT1 and all the auxiliary photodetectors PT2. The user's press can generate a synchronous sensing signal. The control module can determine whether the interference is from foreign objects such as water or the user's press based on whether a synchronous sensing signal is received, thus enabling the sensing button to distinguish user presses and improving anti-interference capability.

[0039] In one embodiment, the control terminal of the first switch is connected to the first output terminal Out1 of the control module. The first switch Q1 can control the start and stop of the light emitting tube IR according to the signal from the first output terminal Out1 of the control module. The control terminal of the second switch Q2 is connected to the second output terminal Out2 of the control module. The second switch Q2 can control the start and stop of the main light receiving tube PT1 and the auxiliary light receiving tube PT2 according to the signal from the second output terminal Out2 of the control module. The control module turns on the first switch Q1 and the second switch Q2 through the first output terminal Out1 and the second output terminal Out2, enabling the light emitting tube IR, the main light receiving tube PT1 and the auxiliary light receiving tube PT2. After the light emitting tube IR is enabled, it emits light. The main light receiving tube PT1 and the auxiliary light receiving tube PT2 receive the light and generate stable sensing signals. The control module obtains the sensing signals on the corresponding first sampling resistor R1 and the second sampling resistor R2 through the first input terminal In1 and the second input terminal In2.

[0040] In one embodiment, when the photosensitive circuit is in a power-saving scenario, the control module can control the first switch Q1 and / or the second switch Q2 to be turned off through the first output terminal Out1 and / or the second output terminal Out2, so that the light emitting tube IR and / or the main light receiving tube PT1 and the auxiliary light receiving tube PT2 stop working, and the photosensitive circuit is in a power-saving mode.

[0041] In one embodiment, the main optical receiver PT1 and / or the auxiliary optical receiver PT2 set the resistance values ​​of the first sampling resistor R1 and / or the second sampling resistor R2 connected to them according to their distance from the optical transmitter, so as to match the impedance under different signal strengths.

[0042] In one embodiment, the current-limiting resistor R is preferably 10 ohms, the first sampling resistor R1 is preferably 1.5k ohms, and the second sampling resistor is preferably 5.1k ohms.

[0043] In one embodiment, the light emitting diode IR is preferably an infrared emitting diode, and the main light receiving diode PT1 and the auxiliary light receiving diode PT2 are preferably infrared light receiving diodes.

[0044] Figure 2 This is a schematic diagram of the circuit structure of a second embodiment of the photosensitive circuit of this application. Figure 2 As shown, the second embodiment of the photosensitive circuit is similar to... Figure 1 The structures of the light-sensing circuits shown are basically the same, with the only difference being: the second switch unit Q2 is removed, and the first pull-down resistor R3 and the second pull-down resistor R4 are connected. The detection terminal Meas of the control module is grounded through the first pull-down resistor R3, and circuit node A is grounded through the second pull-down resistor R4. For brevity, any parts not mentioned in this embodiment can be found in [reference needed]. Figure 1 The corresponding content in the examples.

[0045] In one embodiment, the detection terminal Meas of the control module is connected to the first pull-down resistor R3, and when the photosensitive circuit is considered to be in performance mode based on the detection signal obtained from the detection terminal Meas, the sampling frequency of the first input terminal In1 and / or the second input terminal In2 can be increased.

[0046] In one embodiment, the light-sensing circuit is preferably implemented using a printed circuit board (PCB).

[0047] In one embodiment, the photosensitive circuit reserves pads on the PCB for the second switch Q2, the first pull-down resistor R3, and the second pull-down resistor R4. The second switch Q2 or either the first pull-down resistor R3 or the second pull-down resistor R4 can be used to connect to the photosensitive circuit. Figure 1 or Figure 2 The illustrated embodiment is implemented.

[0048] Figure 3 This is a schematic diagram of the structure of a sensor button according to an embodiment of this application. Figure 3As shown, the inductive button of this application includes: a circuit board, a button panel, and the aforementioned photosensitive circuit. The circuit board is arranged parallel to the button panel. On the circuit board, the button panel has a light emitting tube IR, a main light receiving tube PT1, and all auxiliary light receiving tubes PT2 (only two PT2 are shown in the figure, but this application is not limited to this) of the photosensitive circuit. When the button panel is subjected to a contact operation or a non-contact sensing operation, the light emitted by the light emitting tube IR can change, thereby changing the sensing signals emitted by the main light receiving tube PT1 and all auxiliary light receiving tubes PT2.

[0049] In one embodiment, on the circuit board, the light emitting diode IR and the main light receiving diode PT1 are arranged horizontally, an auxiliary light receiving diode PT2 and the light emitting diode IR are arranged vertically, and multiple auxiliary light receiving diodes PT2 are arranged horizontally.

[0050] In one embodiment, the distance between the main optical receiver PT1 and the optical emitter IR is less than the distance between the main optical receiver PT1 and any one of the auxiliary optical receivers PT2.

[0051] In one embodiment, the sensing button is configured such that the main light receiver PT1 and the auxiliary light receiver PT2 are located in the projection area of ​​the button panel on the circuit board according to the actual working conditions, so that there is a gravity height difference between the main light receiver PT1 and all the auxiliary light receivers PT2 in their spatial positions.

[0052] In one embodiment, the diameter of the button panel is 12~30mm.

[0053] Specifically, when the button panel is contaminated with external objects such as water or liquid that can interfere with the light sensor, the water or liquid will detach from the button panel surface due to its own gravity. Since there is a gap between the main light receiver PT1 and the auxiliary receiver PT2, the water or liquid cannot interfere with both the main receiver PT1 and the auxiliary receiver PT2 at the same time. The asynchronous sensing signal caused by the interference of the water or liquid can be distinguished at the input terminals (i.e., In1 and In2) of the control module. When the user presses the button panel, the sensing signal changes synchronously in the main receiver PT1 and the auxiliary receiver PT2. The control module recognizes that the user is pressing the button by observing the synchronization of the sensing signals at the input terminals (i.e., In1 and In2).

[0054] The photosensitive circuit and sensing button provided in this application include a light emitting tube IR, a main light receiving tube PT1, at least one auxiliary light receiving tube PT2, and a control module. The main receiving tube PT1 and all the auxiliary receiving tubes PT2 can receive light emitted from the light emitting tube IR. The main receiving tube PT1 and the auxiliary receiving tubes PT2 can output sensing signals by changing the received light, thereby increasing the stability of the photosensitive circuit and the sensing button.

[0055] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the appended claims.

Claims

1. A photosensitive circuit, characterized in that, The photosensitive circuit includes: a light emitting tube, a main light receiving tube, and at least one auxiliary light receiving tube; The anode of the light-emitting tube is connected to the output terminal of the power supply, and the cathode of the light-emitting tube is grounded. The input terminals of both the main optical receiver and the auxiliary optical receiver are connected to the power supply. The output terminals of both the main optical receiver and the auxiliary optical receiver are connected to a circuit node, and the circuit node is connected to the ground wire. The main optical receiver and the auxiliary optical receiver are used to receive the light emitted by the optical transmitter and output corresponding sensing signals through the output terminals.

2. The photosensitive circuit according to claim 1, characterized in that, The light sensing circuit further includes: a control module and a first switching element; The first switch is connected in series between the cathode of the light emitting tube and the ground wire, and the control terminal of the first switch is connected to the first output terminal of the control module.

3. The photosensitive circuit according to claim 1, characterized in that, The photosensitive circuit also includes: a control module and a second switching device; The second switch is connected in series in the wiring between the circuit node and the ground wire, and the control terminal of the second switch is connected to the second output terminal of the control module.

4. The photosensitive circuit according to claim 1, characterized in that, The photosensitive circuit also includes: a control module, a first pull-down resistor, and a second pull-down resistor; Wherein, one end of the first pull-down resistor is connected to the detection terminal of the control module, and the other end is connected to the ground wire; One end of the second pull-down resistor is connected to the circuit node, and the other end is connected to the ground wire.

5. The photosensitive circuit according to claim 3 or 4, characterized in that, The photosensitive circuit further includes a first sampling resistor and / or a second sampling resistor; The first sampling resistor is located between the output terminal of the main optical receiver tube and the circuit node; The second sampling resistor is located between the output terminal of the auxiliary optical receiver tube and the circuit node; The first input terminal of the control module is connected to the output terminal of the main optical receiver tube; The second input terminal of the control module is connected to the output terminal of the auxiliary optical receiver tube.

6. A sensor button, characterized in that, Includes the photosensitive circuit as described in any one of claims 1 to 5.

7. The sensor button according to claim 6, characterized in that, The inductive button also includes a button panel and a circuit board; The circuit board is provided with the light-sensing circuit. The circuit board is arranged parallel to the button panel. On the circuit board, and within the projection area of ​​the button panel on the circuit board, the light emitting tube, the main light receiving tube, and all the auxiliary light receiving tubes of the light-sensing circuit are provided.

8. The sensor button according to claim 7, characterized in that, On the circuit board, the light emitting tube and the main light receiving tube are arranged horizontally; and / or one of the auxiliary light receiving tubes and the light emitting tube are arranged vertically, and multiple of the auxiliary light receiving tubes are arranged horizontally.

9. The sensor button according to claim 8, characterized in that, The distance between the main optical receiver and the optical emitter is less than the distance between the main optical receiver and any of the auxiliary optical receivers.

10. The sensor button according to claim 7, characterized in that, The diameter of the sensing panel of the sensing button is in the range of 12mm to 30mm.

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