Knob and sensing circuit thereof
By setting a knob and its sensing circuit on the touch screen, the rotation and pressing states are determined by the change in electrical connection between the sensing electrode and the common electrode. This solves the problem that drivers need to be distracted by looking at the screen when adjusting vehicle settings, thus improving driving safety and convenience.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- NOVATEK MICROELECTRONICS CORP
- Filing Date
- 2024-10-30
- Publication Date
- 2026-05-05
AI Technical Summary
In existing vehicle central information display systems, drivers need to be distracted by looking at the touch screen when adjusting environmental settings, which affects driving safety.
A knob is set on the touch screen. The rotation direction and pressing state of the knob are determined by the change in electrical connection between the sensing electrode and the common electrode. The sensing circuit is used to analyze the sensing signal to achieve distraction-free operation.
It enables convenient adjustment of vehicle environment settings without compromising driving safety, thereby improving the convenience and safety of driver operation.
Smart Images
Figure CN121979403A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a knob sensing technology, and more particularly to a sensing technology for knobs on a touchscreen. Background Technology
[0002] Touchscreen functionality is becoming increasingly common in vehicle center information display (CID) systems. When the car's environmental settings (such as air conditioning temperature and car audio volume) need to be adjusted, the driver must focus more on the touchscreen and the relevant settings displayed on the screen, thus affecting driving safety.
[0003] To improve driving safety, a knob on the touchscreen can be used in the central information display system. This involves placing a physical knob on the touchscreen, allowing the driver to easily adjust settings without having to look at the displayed values. Summary of the Invention
[0004] The main objective of this invention is to provide a knob on a touchscreen and its associated sensing circuit.
[0005] An embodiment of the present invention discloses a knob disposed on a touch screen. The touch screen includes a first touch sensing unit, a second touch sensing unit, and a third touch sensing unit. The knob includes a bottom surface and a first connecting portion. The bottom surface includes a sensing electrode aligned with the first touch sensing unit; a first common electrode aligned with the second touch sensing unit and receiving a first reference voltage from the second touch sensing unit; and a second common electrode aligned with the third touch sensing unit and receiving a second reference voltage from the third touch sensing unit. When the knob is rotated, the first connecting portion is used to control whether the sensing electrode is connected to the first common electrode and the second common electrode. A touch sensing circuit of the touch screen determines the rotation direction of the knob based on the signal change of the first touch sensing unit.
[0006] Another embodiment of the present invention discloses a sensing circuit coupled to a knob. The sensing circuit includes a receiving circuit and a processing circuit. The receiving circuit receives a signal change from the knob. The processing circuit, coupled to the receiving circuit, determines the rotation direction of the knob based on the signal change. The signal change is received by a first touch sensing unit aligned and coupled to a sensing electrode of the knob, and the signal change is generated based on whether the sensing electrode is conductive with a first common electrode and a second common electrode of the knob. Attached Figure Description
[0007] Figure 1 This is a schematic diagram of the bottom of a knob.
[0008] Figure 2 This is a schematic diagram of another type of knob.
[0009] Figure 3 This is a schematic diagram of a knob according to Embodiment 1 of the present invention.
[0010] Figure 4 The detailed structure of the sensing electrode and the common electrode ring is shown in a disassembled manner.
[0011] Figure 5 and Figure 6 It shows Figure 3 A side view of the electrode ring configuration in the knob.
[0012] Figure 7 This is a schematic diagram of another knob in an embodiment of the present invention.
[0013] Figure 8 The detailed structure of the sensing electrode and the common electrode ring is shown in a disassembled manner.
[0014] Figure 9 and Figure 10 It shows Figure 7 A side view of the electrode ring configuration in the knob.
[0015] Figures 11A to 11D The sensor system is shown in four different states of the knob.
[0016] Figure 12 The correspondence between the equivalent capacitance value and the sensed signal is shown.
[0017] Figure 13 The diagram illustrates the different states corresponding to the rotation of the knob.
[0018] Figure 14 The diagram illustrates how pressing the knob corresponds to different states.
[0019] Figure 15 The diagram illustrates how to determine the knob's state based on the correspondence between the equivalent capacitance value and the sensing signal, along with a threshold value.
[0020] Figure 16 This is a schematic diagram of the signal distribution of the touch sensing unit corresponding to the sensing electrode in an embodiment of the present invention.
[0021] Figure 17 This is a schematic diagram of the conductor component of the knob in Embodiment 1 of the present invention.
[0022] The reference numerals in the attached figures are explained as follows:
[0023] 10, 20, 30, 70, 170 knobs
[0024] RA, RB, RX sensing electrodes
[0025] θ rotation angle
[0026] COM, COM1, COM2, COM3 common electrode
[0027] 300, 700 touchscreens
[0028] S1~S4 Touch sensing units
[0029] 402 Sensing Electrode Ring
[0030] 404, 414, 424, 804 electrode posts
[0031] Connecting posts 406, 408, 806_1, 806_2, 806_3
[0032] 412, 422, 802 Common electrode ring
[0033] 806 Connecting Part
[0034] 900 Pressing spring
[0035] 110 Sensing System
[0036] 1100 Sensing Circuit
[0037] 1102 Receiver Circuit
[0038] 1104 Processing Circuit
[0039] VRX sensing signal
[0040] 0C, 1C, 2C, 3C states
[0041] TH1~TH3 Critical Values
[0042] 1700 metal layer
[0043] 1702 Rubber Layer
[0044] 1704 Housing Detailed Implementation
[0045] Figure 1 This is a schematic diagram of the bottom of a knob 10. (For example...) Figure 1As shown, knob 10 can be attached to a touchscreen. The bottom of knob 10 includes an electrode RA, the position of which can be changed by rotating knob 10. When a user touches knob 10, the potential of electrode RA becomes ground potential through knob 10 and the user. When the sensing circuit on the touchscreen senses the user rotating knob 10 via the touch electrodes, the sensing circuit can determine the rotation direction and angle θ of knob 10 by sensing the position of electrode RA. Furthermore, when the user touches knob 10, the potential of electrode RA changes, and the touchscreen also senses the signal. The sensing signal information related to the position of electrode RA is then transmitted to the backend sensing circuit (such as the touch sensor chip used to control the touchscreen), which determines the state of knob 10 based on the distribution of the sensing signal's location. For example, the sensing circuit can use a suitable algorithm to analyze the sensing signal to determine the position of electrode RA, thereby determining the rotation direction and angle θ of knob 10.
[0046] Figure 2 This is a schematic diagram of another type of knob 20. (For example...) Figure 2 As shown, the knob 20 includes sensing electrodes RA and RB and a common electrode COM. Depending on the state of the knob 20, the sensing electrode RA can be selectively connected to or disconnected from the common electrode COM, and the sensing electrode RB can be selectively connected to or disconnected from the common electrode COM.
[0047] The knob 20 is attached to a touchscreen with multiple touch-sensitive electrodes. A touch-sensing chip or Touch with Display Driver (TDDI) applies a ground signal to the first touch-sensing electrode corresponding to a common electrode COM. The common electrode COM then senses the ground signal, causing its potential to become ground. When sensing electrodes RA or RB are electrically connected to the common electrode COM, their potentials also become ground. At this time, the second touch-sensing electrode corresponding to RA or the third touch-sensing electrode corresponding to RB on the touchscreen also senses the ground potential of RA or RB. The touch-sensing chip or TDDI can then determine the operation of the knob 20 based on the signals detected by the second or third touch-sensing electrodes. It is important to note that sensing electrodes RA, RB, and the common electrode COM may also correspond to multiple second, third, or first touch-sensing electrodes.
[0048] In another embodiment, the sensing electrodes RA and RB can be connected or disconnected from the common electrode COM when the knob 20 is rotated via a mechanism, such as electrode shape or structure. Therefore, when the knob 20 is rotated, the connection between the sensing electrodes RA and RB and the common electrode COM changes, and the downstream sensing circuit can determine the state of the knob 20 based on the sensed signals. For example, in... Figure 2 In the upper left diagram, sensing electrodes RA and RB are simultaneously connected to the common electrode COM; this is the first state of knob 20. When knob 20 is rotated, the electrical connection between sensing electrode RA and the common electrode COM is broken, while sensing electrode RB remains connected to the common electrode COM. Figure 2 As shown in the upper right figure, this is the second state of knob 20; when knob 20 is rotated again, the electrical connection between sensing electrode RB and common electrode COM is broken, while sensing electrode RA and common electrode COM remain electrically connected, as shown in the figure. Figure 2 As shown in the lower left figure, this is the third state of knob 20; when knob 20 is rotated again, the electrical connection between sensing electrodes RA and RB and the common electrode COM is simultaneously disconnected, as shown in the figure below. Figure 2 As shown in the lower right image, this is the fourth state of knob 20. These four states can be detected by the touch-sensing chip or touch-driver integrated chip on the touchscreen.
[0049] In this case, the touch sensing chip can determine whether the knob 20 is rotating clockwise or counterclockwise based on the continuous state changes of the knob 20 (i.e., changes in the electrical connection relationship between these electrodes).
[0050] Figure 3 This is a schematic diagram of a knob 30 according to an embodiment of the present invention, showing plan views of various positions of the knob 30. The knob 30 includes a sensing electrode RX and two common electrodes COM1 and COM2. By rotating the knob 30, the common electrodes COM1 and COM2 can be electrically connected or not electrically connected to the sensing electrode RX in different states to generate different sensing signal quantities.
[0051] like Figure 3As shown in the bottom plan view on the left, the knob 30 can be disposed on a touch screen 300, where each segment represents a touch sensing unit on the touch screen 300. This touch sensing unit can represent a touch sensing electrode, which is the smallest unit for touch sensing on the touch screen 300. In one embodiment, the touch sensing electrode can act as a common electrode during the display period of the touch screen 300, and as a touch sensing electrode during the touch period. In another embodiment, the touch screen 300 is an OLED touch screen, so the touch sensing electrode will not act as a common electrode during the display period like an LCD panel. The touch sensing chip on the touch screen or the sensing circuit within the touch sensing chip can determine whether there is a touch or whether the sensing electrode RX of the knob 30 is sensed based on the change in capacitance on the touch sensing unit.
[0052] like Figure 3 As shown, the sensing electrode RX and the common electrodes COM1 and COM2 can be fixed above multiple touch sensing units and aligned with those touch sensing units. In another embodiment, the sensing electrode RX and / or the common electrodes COM1 and COM2 can also be located above only one touch sensing unit, and thus within the sensing range of only one touch sensing unit.
[0053] In one embodiment, the sensing circuit can apply a specific voltage to the touch sensing unit located below the common electrodes COM1 and COM2, which can be a ground voltage. In another embodiment, the sensing circuit can apply different reference voltages to the touch sensing unit located below the common electrodes COM1 and COM2. For example, such as... Figure 3 As shown, the touch unit below the sensing electrode RX is the first touch sensing unit S1, the touch sensing unit below the common electrode COM1 is the second touch sensing unit S2, and the touch sensing unit below the common electrode COM2 is the third touch sensing unit S3. The sensing circuit can apply a ground voltage to the second touch sensing unit S2 and a negative voltage to the third touch sensing unit S3. By applying different voltages to the second touch sensing unit S2 or the third touch sensing unit S3, the sensing circuit can make the capacitance change (or signal quantity, or signal change quantity) sensed by the first touch sensing unit S1 more significant.
[0054] When the knob is rotated, the sensing electrode RX may be electrically connected to the common electrodes COM1 and COM2 individually, simultaneously, or without any electrical connection. The sensing circuit applies a drive signal to the first touch sensing unit S1 below the sensing electrode RX and receives the sensing signal from the first touch sensing unit S1. The sensing circuit can determine the connection state between the sensing electrode RX and the common electrodes COM1 and COM2 based on the signal strength of the sensed signal, and determine the knob's operation based on the signal strength read over a continuous period of time.
[0055] In various embodiments of the present invention, the internal structure of the knob 30 can be designed to change the state of whether the common electrode COM1 or COM2 is electrically connected to the sensing electrode RX when the knob 30 is rotated, thereby allowing the sensing circuit to determine the rotation direction and angle of the knob 30 based on the sensing signal quantity of the sensing electrode RX. Figure 3 As shown in the intermediate rotating layer plan view, the sensing electrode RX and common electrodes COM1 and COM2 are each coupled to a corresponding electrode ring. The electrode ring of common electrode COM1 is located inside the electrode ring of sensing electrode RX, and the electrode ring of common electrode COM2 is located outside the electrode ring of sensing electrode RX. The electrode rings of common electrodes COM1 and COM2 have a serrated structure. When the knob 30 is rotated, the electrode rings of common electrodes COM1 and COM2 rotate accordingly, causing the serrated protrusions to contact the electrode ring of sensing electrode RX when rotated to certain angles, thereby electrically connecting common electrode COM1 or COM2 and sensing electrode RX.
[0056] Figure 4 The detailed structure of the electrode rings for the sensing electrode RX and common electrodes COM1 and COM2 is shown in disassembly. The sensing electrode RX is coupled to a sensing electrode ring 402, which has an electrode post 404 and connecting posts 406 and 408. The common electrode COM1 is coupled to a common electrode ring 412 and an electrode post 414. The common electrode COM2 is also coupled to a common electrode ring 422 and an electrode post 424. Please refer to... Figure 4 Matching Figure 3As shown, electrode post 404 is disposed above the sensing electrode RX on the touch screen 300 and connected between the sensing electrode RX and the sensing electrode ring 402 on the touch screen 300, so that the sensing electrode RX and the sensing electrode ring 402 are electrically connected to each other through electrode post 404. Similarly, electrode post 414 is disposed above the common electrode COM1 on the touch screen 300 and connected between the common electrode COM1 and the common electrode ring 412 on the touch screen 300, so that the common electrode COM1 and the common electrode ring 412 are electrically connected to each other through electrode post 414; electrode post 424 is disposed above the common electrode COM2 on the touch screen 300 and connected between the common electrode COM2 and the common electrode ring 422 on the touch screen 300, so that the common electrode COM2 and the common electrode ring 422 are electrically connected to each other through electrode post 424. It should be noted that, in this invention, the sensing electrode ring 402, electrode post 404, and connecting posts 406 and 408 can be regarded as conductor components coupled to the sensing electrode RX, or as part of the sensing electrode RX; similarly, the common electrode ring 412 and electrode post 414 can be regarded as conductor components coupled to the common electrode COM1, or as part of the common electrode COM1; the common electrode ring 422 and electrode post 424 can be regarded as conductor components coupled to the common electrode COM2, or as part of the common electrode COM2.
[0057] Furthermore, the connecting post 406 can be a conductor protruding from the sensing electrode ring 402 toward the common electrode COM1, and it is electrically connected to the sensing electrode ring 402. Correspondingly, the common electrode ring 412 of the common electrode COM1 has a serrated structure. When the knob 30 is rotated to certain angles, the connecting post 406 can contact the serrated protrusions on the common electrode ring 412, so that the common electrode ring 412 is electrically connected to the sensing electrode ring 402, thereby electrically connecting the common electrode COM1 to the sensing electrode RX; when the knob 30 is rotated to other angles, the position of the connecting post 406 corresponds to the serrated recesses on the common electrode ring 412, so it does not contact the common electrode ring 412, so that the common electrode ring 412 is not electrically connected to the sensing electrode ring 402, thereby electrically connecting the common electrode COM1 to the sensing electrode RX.
[0058] Similarly, the connecting post 408 can be a conductor protruding from the sensing electrode ring 402 toward the common electrode COM2, and it is electrically connected to the sensing electrode ring 402. Correspondingly, the common electrode ring 422 of the common electrode COM2 has a serrated structure. When the knob 30 is rotated to certain angles, the connecting post 408 can contact the serrated protrusions on the common electrode ring 422, so that the common electrode ring 422 is electrically connected to the sensing electrode ring 402, thereby electrically connecting the common electrode COM2 to the sensing electrode RX; when the knob 30 is rotated to other angles, the position of the connecting post 408 corresponds to the serrated recesses on the common electrode ring 422, so it does not contact the common electrode ring 422, so that the common electrode ring 422 is not electrically connected to the sensing electrode ring 402, thereby electrically connecting the common electrode COM2 to the sensing electrode RX.
[0059] In one embodiment, when the knob 30 is rotated, the sensing electrode ring 402 remains stationary, while the common electrode rings 412 and 422 rotate with the knob 30. In this case, the positions of the connecting posts 406 and 408 on the sensing electrode ring 402 remain fixed, while as the common electrode rings 412 and 422 rotate, the serrated protrusions and recesses sequentially overlap the positions of the connecting posts 406 and 408, thereby changing the contact state between the common electrode rings 412 and 422 and the corresponding connecting posts 406 and 408, and thus changing the electrical connection state between the common electrodes COM1 and COM2 and the sensing electrode RX. In this case, the signal quantity of the touch sensing unit below the sensing electrode RX can be changed, and the subsequent sensing circuit (e.g., the sensing circuit in the touch sensing chip of the touch screen) can determine the rotation direction and angle of the knob 30 accordingly.
[0060] In another embodiment, when the knob 30 is rotated, the common electrode rings 412 and 422 remain stationary, while the sensing electrode ring 402 rotates with the knob 30. In this case, the positions of the connecting posts 406 and 408 on the sensing electrode ring 402 continuously change during rotation, while the positions of the serrations on the common electrode rings 412 and 422 remain unchanged. This also changes the contact state between the common electrode rings 412 and 422 and the corresponding connecting posts 406 and 408, thereby enabling the determination of the rotation of the knob 30.
[0061] To more clearly illustrate the structure of the knob of this invention, Figure 5A side view of the electrode ring configuration in the knob 30 is further shown, illustrating cross-sections at positions A and B. Position A is where the connecting posts 406 and 408 are located. In this example, the knob 30 is rotated to the position of the connecting posts 406 and 408, where the common electrode rings 412 and 422 are both serrated protrusions. Therefore, the common electrode rings 412 and 422 contact the connecting posts 406 and 408 respectively, forming a conductive / electrical connection. Position B is the position without the connecting posts 406 and 408, and the common electrode rings 412 and 422 are serrated recesses. Their length is shorter and does not overlap with the sensing electrode ring 402, thus they do not contact the connecting posts 406 and 408.
[0062] Figure 6 The cross-sections at other locations C and D are shown. Location C is the position of the sensing electrode RX on the panel. As can be seen from the corresponding side view, the sensing electrode ring 402 is electrically connected to the sensing electrode RX via the electrode post 404. Location D is the position of the common electrode COM1 on the panel. As can be seen from the corresponding side view, the common electrode ring 412 is electrically connected to the common electrode COM1 via the electrode post 414.
[0063] As described above, the knob 30 in this case only includes a single sensing electrode RX. For the downstream sensing circuit, the sensing signal used to determine knob operation only needs to be received through this single sensing electrode RX. More specifically, the sensing circuit only needs to receive the sensing signal from the touch sensing unit below the sensing electrode RX, without considering signals from other locations, and without needing to receive sensing signals from multiple sensing electrodes for more complex comparisons and judgments. In this case, the sensing circuit only needs one receiving channel, simplifying the receiving end structure and operation of the sensing circuit, thereby reducing costs.
[0064] It is worth noting that the above Figures 3-6 The architecture of the knob 30 shown is only one of many embodiments of the present invention. In other embodiments, different numbers of common electrodes can be used to achieve more flexible signal change judgment. In one embodiment, additional common electrodes can also be added to realize knob press detection.
[0065] Figure 7 This is a schematic diagram of another knob 70 according to an embodiment of the present invention. The structure of knob 70 is similar to... Figure 3 The knobs in the diagram are similar to those in component 30; therefore, components with similar functions are represented by the same symbol. For example... Figure 7As shown, the difference between knob 70 and knob 30 is that knob 70 also includes a common electrode COM3, which is configured to implement a press function. More specifically, the back-end sensing circuit can determine whether knob 70 is pressed based on whether the common electrode COM3 (and other common electrodes COM1 and COM2) is electrically connected to the sensing electrode RX. Similarly, knob 70 is disposed on touch screen 700, and the common electrode COM3 can be disposed above multiple touch sensing units of touch screen 700 (i.e., Figure 7 The fourth touch sensing unit S4 shown can determine whether the common electrode COM3 and the sensing electrode RX are electrically connected by applying the same or different reference voltages to the fourth touch sensing unit S4 and by using the signal quantity sensed by the first touch sensing unit S1.
[0066] Figure 8 The detailed structure of the electrode rings for the sensing electrode RX and the common electrodes COM1, COM2, and COM3 is shown in a disassembled manner. The arrangement of the electrode rings and electrode posts for the sensing electrode RX and the common electrodes COM1 and COM2 is similar to... Figure 4 The same applies as shown, and will not be repeated here. The common electrode COM3 is coupled to a common electrode ring 802, an electrode post 804, and a connecting portion 806. Please refer to... Figure 8 Matching Figure 7 As shown, electrode post 804 is disposed above the common electrode COM3 on the touch screen 300 and connects between the common electrode COM3 and the common electrode ring 802 on the touch screen 300, so that the common electrode COM3 and the common electrode ring 802 are electrically connected to each other through electrode post 804. It should be noted that in this embodiment, the common electrode ring 802, electrode post 804 and connecting portion 806 can be regarded as a conductor assembly coupled to the common electrode COM3, or as part of the common electrode COM3.
[0067] Furthermore, the common electrode ring 802 is located on the outermost side of all electrode rings, while the connecting portion 806 can be a conductor extending inward from the common electrode ring 802, electrically connected to it, and extending to overlap with the innermost common electrode ring 412. Therefore, when the knob is pressed, the connecting portion 806 can contact the sensing electrode ring 402 and the common electrode rings 412 and 422, so that the common electrode COM3 is electrically connected to the sensing electrode RX and the common electrodes COM1 and COM2.
[0068] It is worth noting that when the knob 70 is rotated, the common electrode ring 802 of the common electrode COM3 can be designed to remain fixed, or it can be designed to rotate with the knob 70 depending on the system requirements. As long as the pressing operation of the knob 70 can change the electrical connection between the common electrode COM3 and the sensing electrode RX, thereby changing the signal quantity generated by the sensing electrode RX, all related implementations should fall within the scope of this invention.
[0069] To more clearly explain the structure of knob 70 and the operation of common electrode COM3, Figure 9 A side view of the electrode ring configuration in the knob 70 is further shown, illustrating cross-sections at positions A and B. Position A includes connecting posts 406 and 408, and is also the location of the connecting portion 806 of the common electrode ring 802. The side view corresponding to position A shows that the connecting portion 806 extends above the electrode rings 422, 402, and 412, and vertical connecting posts 806_1, 806_2, and 806_3 are positioned above each electrode ring. Connecting posts 806_1, 806_2, and 806_3 can be considered as conductor assemblies coupled to the connecting portion 806, or as part of the connecting portion 806.
[0070] like Figure 9 As shown, the knob 70 includes a pressing spring 900, which is disposed between the common electrode rings 802 and 422. When the knob 70 is not pressed, the pressing spring 900 can push the common electrode ring 802 to a higher position, so that there are slight gaps between the connecting posts 806_1, 806_2, and 806_3 and the electrode rings 422, 402, and 412 respectively, and they are not electrically connected to each other. At this time, the common electrode COM3 is not electrically connected to the sensing electrode RX and other common electrodes COM1 and COM2. When the knob 70 is pressed, the common electrode ring 802 and the connecting posts 806_1, 806_2, and 806_3 move down to contact the corresponding electrode rings 422, 402, and 412 respectively, so that the common electrode COM3 is electrically connected to the sensing electrode RX and other common electrodes COM1 and COM2. In this situation, the sensing electrode RX can receive signals from the common electrodes COM1 to COM3, so that the sensing circuit at the back end can determine that the knob 70 is pressed.
[0071] Figure 9 The cross-section at position B is shown, which is the position of the common electrode COM3 on the panel. As can be seen from the corresponding side view, the common electrode ring 802 is electrically connected to the common electrode COM3 through the electrode post 804. Figure 10 The cross-sections of other positions C and D in knob 70 are also shown, corresponding to the positions of sensing electrode RX and common electrode COM1 on the panel, respectively. Detailed structures are shown in the diagram. Figure 6 The similarities are not elaborated here.
[0072] Based on the structure of the knob 70 described above, under different rotation or pressing states, the sensing electrode RX can be electrically connected to different numbers of common electrodes COM1 to COM3, thereby generating different levels of signal quantity in the touch sensing unit below the sensing electrode RX. The sensing circuit can then determine the state of the knob 70 by detecting the signal quantity of these touch sensing units, thereby determining the rotation direction and angle of the knob, and simultaneously realizing the pressing judgment.
[0073] In one embodiment, the knob 70 is set to have four different states. Figures 11A to 11D The diagram illustrates a sensing system with the knob 70 in four different states, including the knob 70 and a sensing circuit 1100 for detecting the knob 70. In one embodiment, the knob 70 may be located on a touchscreen, and the sensing circuit 1100 may be used to control / drive the touchscreen and detect the operation of the knob 70. In another embodiment, the sensing circuit 1100 may be an integrated circuit (IC) embedded in a chip, which can be connected to a touch sensing unit on the touchscreen corresponding to the electrodes of the knob 70 through one or more ports of the chip for detecting the knob 70.
[0074] In detail, the sensing circuit 1100 includes a receiving circuit 1102 and a processing circuit 1104. The receiving circuit 1102 receives a sensing signal VRX from the knob 70. More specifically, the sensing signal VRX received by the receiving circuit 1102 comes from a touch sensing unit corresponding to the sensing electrode RX, such as one or more touch sensing units located below the sensing electrode RX (i.e., the first touch sensing unit S1 in the aforementioned embodiment). In one embodiment, the receiving circuit 1102 may output a drive signal to the touch sensing unit located below the sensing electrode RX to receive the sensing signal VRX from that touch sensing unit(s). The processing circuit 1104 is coupled to the receiving circuit 1102 and can determine the state of the knob 70 based on the signal intensity of the sensing signal VRX. For example, the processing circuit 1104 includes an algorithm that can be used to determine the state of the knob 70, such as the angle to which it is rotated or whether it is pressed, based on the signal intensity distribution of the touch sensing units below the sensing electrode RX.
[0075] Furthermore, the sensing circuit 1100 may also include a driving circuit (not shown) that, while detecting the knob 70, applies a reference voltage, such as a ground voltage, to the corresponding touch sensing units (e.g., touch sensing units located below the common electrodes COM1-COM3). This reference voltage can be coupled to the common electrodes COM1-COM3, and depending on whether each common electrode COM1-COM3 is electrically connected to the sensing electrode RX, a signal of different magnitude can be generated on the sensing electrode RX. This signal is then coupled to the touch sensing unit below the sensing electrode RX through the parasitic capacitance between the knob 70 and the panel, thereby generating a sensing signal VRX that can be detected by the sensing circuit 1100.
[0076] Please refer to Figure 7 , Figure 9 Matching Figures 11A to 11D As shown. In the structural design of knob 70, common electrodes COM1 and COM2 are used for rotation detection. When knob 70 is rotated to different angles, different numbers of common electrodes COM1 and COM2 may be electrically connected to sensing electrode RX, thereby generating different signal quantities in the touch sensing unit below sensing electrode RX, which correspond to different magnitudes of sensing signals VRX. Common electrode COM3 is used for press detection, such as... Figure 9 As shown, when the knob 70 is pressed, the common electrodes COM1 to COM3 are electrically connected to the sensing electrode RX, thus generating a larger signal in the touch sensing unit below the sensing electrode RX.
[0077] As described above, knob 70 is set to have four different states, which are represented as 0C, 1C, 2C and 3C respectively. Figure 11A The diagram shows state 0C. State 0C indicates that when knob 70 is rotated to a certain angle, both common electrodes COM1 and COM2 are not electrically connected to the sensing electrode RX. At this time, knob 70 is not pressed, so common electrode COM3 is also not electrically connected to the sensing electrode RX. In this case, there is no signal from the common electrode to the sensing electrode RX, and therefore no signal from the touch sensing unit below it.
[0078] Figure 11B The diagram shows state 1C, which indicates that when knob 70 is rotated to a certain angle, the common electrode COM1 is electrically connected to the sensing electrode RX, while the common electrode COM2 is not electrically connected to the sensing electrode RX. At this time, knob 70 is not pressed, so the common electrode COM3 is not electrically connected to the sensing electrode RX. In this case, the sensing electrode RX is only electrically connected to one common electrode, resulting in a weak signal.
[0079] Figure 11CState 2C is shown. State 2C indicates that when knob 70 is rotated to a certain angle, both common electrodes COM1 and COM2 are electrically connected to sensing electrode RX. At this time, knob 70 is not pressed, so common electrode COM3 is not electrically connected to sensing electrode RX. In this case, sensing electrode RX and the two common electrodes are electrically connected, resulting in a larger signal (compared to state 1C).
[0080] Figure 11D The diagram shows state 3C, which indicates that when knob 70 is pressed, the common electrodes COM1 to COM3 are all electrically connected to the sensing electrode RX. In this case, the sensing electrode RX and the three common electrodes are electrically connected, resulting in the maximum signal strength.
[0081] In this way, by detecting the signal, the processing circuit 1104 in the sensing circuit 1100 can determine the state of the knob 70, thereby determining the rotation direction and angle of the knob 70 and whether the knob 70 is pressed, and thus realize the various operations of the knob 70.
[0082] As described above, the sensing circuit 1100 can receive a sensing signal VRX from the touch sensing unit corresponding to the sensing electrode RX, and determine the state of the knob 70 by the signal magnitude of the sensing signal VRX. Since the detected touch sensing unit is located below the sensing electrode RX, close to but not electrically connected to the sensing electrode RX, the signal on the sensing electrode RX will generate a capacitance change in the touch sensing unit through capacitive coupling. In addition, the signal on the sensing electrode RX also comes from the common electrodes COM1 to COM3 that are electrically connected to it and applied a ground voltage. The more common electrodes that are electrically connected, the greater the equivalent capacitance change generated in the touch sensing unit below the sensing electrode RX. When performing knob detection, the drive signal output by the sensing circuit 1100 will charge and discharge the capacitor on the touch sensing unit(s). The current generated during the charging and discharging process is received by the sensing circuit 1100 as the sensing signal VRX.
[0083] In one embodiment, the receiving circuit 1102 in the sensing circuit 1100 includes an analog front-end (AFE) circuit, which can be coupled to a touch sensing unit through a sensing endpoint of the chip of the sensing circuit 1100. The current generated by the touch sensing unit is received by the analog front-end circuit through the sensing endpoint. For example, the analog front-end circuit may include a resistor to convert the current from the touch sensing unit into a voltage-form sensing signal VRX, which is then converted into digital form by a back-end analog-to-digital converter (ADC) and transmitted to the processing circuit 1104 for judgment. Corresponding to different capacitance changes on the touch sensing unit, the analog front-end circuit will receive different currents or voltages, so different currents or voltages can be measured at the sensing endpoint of the receiving circuit 1102.
[0084] Figure 12 The diagram illustrates the correspondence between the equivalent capacitance value and the sensing signal VRX. As mentioned above, the sensing signal VRX on the vertical axis can be in voltage or current form. The equivalent capacitance value on the horizontal axis corresponds to the number of common electrodes electrically connected to the sensing electrode RX. Figures 11A to 11D As shown, each common electrode COM1 to COM3 has a coupling capacitance with the corresponding touch sensing unit on the panel. When the sensing electrode RX is electrically connected to any of the common electrodes COM1 to COM3, the equivalent capacitance value detected by the sensing circuit 1100 through the sensing electrode RX is equivalent to the combination of the coupling capacitance of the sensing electrode RX itself and the coupling capacitance corresponding to the connected common electrode. In other words, the more common electrodes the sensing electrode RX is electrically connected to, the larger the corresponding equivalent capacitance value of the sensing electrode RX, and the larger the generated sensing signal VRX. The corresponding relationship is as follows: Figure 12 As shown. Preferably, by well-designing the dimensions of the sensing electrode RX and the common electrodes COM1 to COM3 of the knob, the equivalent capacitance can fall within the linear region, so that the sensing signal VRX detected by the sensing circuit 1100 can effectively reflect the change in the equivalent capacitance.
[0085] Figure 13 The diagram illustrates the rotation of the knob corresponding to different states. When not pressed, the knob can have three states: 0C, 1C, and 2C, depending on the number of common electrodes electrically connected to the sensing electrode RX. For example... Figure 13As shown, in state 0C, the connecting post of the electrode ring of the sensing electrode RX overlaps with the sawtooth recessed portion of the electrode rings of the common electrodes COM1 and COM2, so that neither the common electrodes COM1 nor COM2 are electrically connected to the sensing electrode RX; in state 1C, the connecting post of the electrode ring of the sensing electrode RX overlaps with the sawtooth protrusion of the electrode ring of the common electrode COM1 and the sawtooth recessed portion of the electrode ring of the common electrode COM2, so that only the common electrode COM1 is electrically connected to the sensing electrode RX; in state 2C, the connecting post of the electrode ring of the sensing electrode RX overlaps with the sawtooth protrusion of the electrode rings of the common electrodes COM1 and COM2, so that both the common electrodes COM1 and COM2 are electrically connected to the sensing electrode RX.
[0086] The transition methods between each state are also shown in Figure 13 In this example, the electrode rings of the common electrodes COM1 and COM2 rotate with the knob, while the electrode rings of the common electrode COM3 and the sensing electrode remain fixed. The knob can rotate clockwise or counterclockwise. During clockwise rotation, the knob's state changes in the sequence 0C, 2C, 1C, 0C, 2C, 1C...; during counterclockwise rotation, the knob's state changes in the sequence 1C, 2C, 0C, 1C, 2C, 0C... The knob's sensing circuit can then determine the direction of rotation and calculate the rotation angle based on the changes and sequence of the knob's state over a period of time.
[0087] Therefore, by utilizing the serrated structure of the common electrode ring, the protruding or recessed serrated portions can be adjusted to correspond to the connecting posts on the sensing electrode ring when the knob is rotated, thereby changing the number of common electrodes electrically connected to the sensing electrode RX at any time. Thus, the serrated structure of the common electrode ring needs to be well-designed to achieve changes between different states 0C to 2C during rotation. In this example, the serrations on the electrode ring of the common electrode COM1 can be designed to be wider, while the serrations on the electrode ring of the common electrode COM2 can be narrower, and each serration on both electrode rings corresponds to and rotates synchronously, so that the state of the knob satisfies the predetermined change pattern when rotating clockwise and counterclockwise. It should be noted that the above-described method of using a serrated mechanism to change the electrode coupling when the knob is rotated is only one of many embodiments of the present invention. In other embodiments, as long as the number of common electrodes electrically connected to the sensing electrode RX in the knob can change with knob operation, and the change method can be used to determine the rotation direction and / or angle of the knob, the related knob structure and determination method should fall within the scope of the present invention.
[0088] Figure 14 The diagram illustrates the different states corresponding to pressing the knob. As mentioned above, when not pressed, the knob may be in one of three states ranging from 0°C to 2°C. Figure 14Taking state 0C as an example; when the knob is pressed, the pressing spring 900 is pressed down, so that the common electrodes COM1 to COM3 are simultaneously electrically connected to the sensing electrode RX, and the knob is in state 3C. The knob's sensing circuit can then determine whether it has been pressed based on the knob's state.
[0089] As described above, the different states of the knob, 0C to 3C, correspond to the number of common electrodes electrically connected to the sensing electrode RX, which in turn correspond to the signal quantity of the touch sensing unit below the sensing electrode RX. The knob's sensing circuit can determine the knob's state based on the magnitude of the signal quantity. In one embodiment, the knob's state may affect the signal quantity distribution of multiple touch sensing units near the sensing electrode RX. To achieve more accurate knob state determination, the algorithm in the processing circuit can refer to the signal quantity distribution of these touch sensing units and use appropriate threshold values to determine the knob's state.
[0090] For example, such as Figure 15 As shown, in Figure 12 In the correspondence between the equivalent capacitance value and the sensing signal VRX, states 0C to 3C correspond to different equivalent capacitances and different sensing signal VRX values, respectively. In this example, the processing circuit can compare the signal strength of the sensing signal VRX with any threshold value TH1 to TH3 to determine which state the knob is in. Specifically, when the signal strength of the sensing signal VRX is less than the threshold value TH1, the knob is determined to be in state 0C; when the signal strength of the sensing signal VRX is greater than the threshold value TH1 but less than the threshold value TH2, the knob is determined to be in state 1C; when the signal strength of the sensing signal VRX is greater than the threshold value TH2 but less than the threshold value TH3, the knob is determined to be in state 2C; and when the signal strength of the sensing signal VRX is greater than the threshold value TH3, the knob is determined to be in state 3C.
[0091] Figure 16 This is a schematic diagram illustrating the signal quantity distribution of the touch sensing units corresponding to the sensing electrode RX in an embodiment of the present invention. It shows exemplary signal quantity (i.e., signal change) distributions under states 0C to 3C, where each cell represents a touch sensing unit. Specifically, the touch sensing unit located at the very center directly below the sensing electrode RX has the largest signal quantity, with values of 0, 50, 100, and 150 under states 0C to 3C, respectively. Therefore, in one embodiment, the threshold values TH1 to TH3 used to determine the knob state can be set to 25, 75, and 125, respectively, to distinguish knob operations under different states. In another embodiment, multiple touch sensing units that may be affected by the sensing electrode RX (such as...) can also be combined... Figure 16The signal quantities of the nine touch sensing units shown are used as the sensing signals VRX received by the sensing circuit, and appropriate threshold settings are used to determine the knob operation. Alternatively, the sensing electrodes RX can be placed above multiple touch sensing units (i.e., the area of the sensing electrodes RX covers the area of multiple touch sensing units), so that the sensing unit can obtain the sensing signals VRX of these touch sensing units, thereby increasing the signal quantity and improving the efficiency of knob operation determination.
[0092] It is worth noting that the purpose of this invention is to provide a knob on a touchscreen and its associated sensing circuit. The knob only requires a single sensing electrode, which simplifies the detection method of the sensing circuit and saves on its cost. Those skilled in the art will be able to make modifications or variations accordingly, and are not limited thereto. For example, Figure 3 or Figure 7 The knob structure described herein is only one of many embodiments of the present invention. In another embodiment, the electrode rings in the knob can also be configured in other ways, for example, the electrode ring for the common electrode COM3 used for press detection can be located on the inner side. Alternatively, in other embodiments, the knob may include more than four electrode rings, and the number of electrode rings provided is not limited to those described in this specification.
[0093] Furthermore, in the above embodiments, the electrode rings of each electrode are arranged horizontally along the knob housing so as to rotate with the rotation of the knob. However, the structure of the present invention is not limited to this. In other embodiments, the position of the electrode rings can be changed, for example, some or all of the electrode rings can be designed as electrode plates perpendicular to the bottom of the knob. As long as the electrode rings can move or rotate with the rotation of the knob, thereby changing the electrical connection between the sensing electrode and the common electrode under different knob states, the related implementations should all fall within the scope of the present invention.
[0094] Furthermore, in embodiments of the present invention, the size of the sensing electrodes can be arbitrarily determined according to system requirements. For example, if two common electrodes COM1 and COM2 are used, the common electrodes COM1 and COM2 can be designed with different sizes to enhance the differentiation between different states. In a preferred embodiment, it is possible to... Figure 7 In the structure of the knob 70, the area ratio of the common electrodes COM1, COM2 and COM3 is designed to be 1:2:3 to achieve the best knob discrimination effect.
[0095] In some embodiments, the knob can be located on a touchscreen, and the knob's sensing circuit can simultaneously possess knob detection and touch sensing functions. In other embodiments, the knob can also be located on a general display screen without touch functionality, or on the casing of a general tablet or electronic device, and is not limited to these. The sensing electrodes and common electrodes in the knob can also be configured in an appropriate manner. For example, the sensing electrode sheet and common electrode sheet can be attached to a predetermined position on the panel, with corresponding electrode posts and electrode rings attached above, and then the knob casing can be placed over the electrode components. Alternatively, the sensing electrode sheet and common electrode sheet can be attached to the knob base, followed by the attachment of electrode posts and electrode rings, and after covering with the casing, the entire knob can be attached to the desired position.
[0096] It should be noted that in the above embodiments, the sensing circuit can apply a reference voltage to the touch sensing unit corresponding to the common electrode. Therefore, the sensing signal on the sensing electrode can be the signal change generated by the reference voltage on the common electrode. In another embodiment, the signal change of the sensing signal can also be generated based on a reference voltage (such as ground voltage) provided by a touch object (such as a user's finger) operating the knob. In this case, a conductor can be provided in the knob, and the conductor can be coupled to the corresponding common electrode inside the knob. Therefore, during knob operation (e.g., when the user's finger rotates the knob), the reference voltage from the touch object can be transmitted to the common electrode through the conductor to provide a signal to the sensing electrode when the common electrode is electrically connected to the sensing electrode, thereby generating a signal on the touch sensing unit corresponding to the sensing electrode. In this way, the touch sensing unit corresponding to the common electrode does not need to receive a separate reference voltage; instead, the reference voltage is provided by the touch object. In another embodiment, a reference voltage can also be applied to the touch sensing unit corresponding to the common electrode. Combined with the voltage signal of the conductor, a larger signal can be obtained, thereby improving the efficiency of knob detection.
[0097] The conductor can be implemented in any suitable manner. In one embodiment, the conductor can be a conductive ring disposed on the surface of the knob, which can contact the touch object when the touch object performs knob operation. Alternatively, the conductor can be or include a metal layer inside the conductor. Figure 17 As shown, the knob 170 has a metal layer 1700 and a rubber layer 1702, and the knob housing 1704 can be used to cover and protect the internal electrodes. The metal layer 1700 is a sheet-like conductor covering the entire bottom of the knob 170, exposed around its perimeter. This is a location easily touched by a touch object when operating the knob, thus allowing the ground voltage from the touch object to be conducted to the corresponding common electrode. In this embodiment, the large parasitic capacitance generated by the large-area sheet-like conductor of the metal layer 1700 provides more signal to the sensing electrodes.
[0098] In summary, this invention proposes a structure for a knob on a touchscreen, as well as a sensing circuit and its operation method for controlling the knob. The knob requires only a single sensing electrode, coupled with multiple common electrodes, to achieve various knob operations. The sensing circuit only needs to detect and receive sensing signals through the single sensing electrode. Depending on the knob's rotation or pressing operation, the sensing electrode can be electrically connected to different numbers of common electrodes in different states, thereby generating different signal quantities on the touch sensing unit corresponding to the sensing electrode. Therefore, the sensing circuit can determine the various knob operations based on the detected signal quantities.
[0099] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A knob disposed on a touch screen, characterized in that, The touchscreen includes a first touch sensing unit, a second touch sensing unit, and a third touch sensing unit, and the knob includes: A bottom surface, comprising: A sensing electrode is aligned with the first touch sensing unit; A first common electrode is aligned with the second touch sensing unit to receive a first reference voltage from the second touch sensing unit; and A second common electrode is aligned with the third touch sensing unit to receive the second reference voltage from the third touch sensing unit; and A first connecting part, which controls whether the sensing electrode is connected to the first common electrode and the second common electrode when the knob is rotated; The touch-sensing circuit of the touchscreen determines the rotation direction of the knob based on the signal change of the first touch-sensing unit.
2. The knob as described in claim 1, characterized in that, The first common electrode or the second common electrode also receives a third reference voltage from a touch object that operates the knob to form the signal change in the first touch sensing unit.
3. The knob as described in claim 2, characterized in that, Also includes: A conductor, coupled to the first common electrode or the second common electrode, is used to receive the third reference voltage from the touch object when the touch object operates the knob.
4. The knob as described in claim 1, characterized in that, The first common electrode and the second common electrode have different sizes.
5. The knob as described in claim 1, characterized in that, The bottom surface also includes a third common electrode, which is electrically connected to the sensing electrode when the knob is pressed, and not electrically connected to the sensing electrode when the knob is not pressed.
6. The knob as described in claim 5, characterized in that, Also includes: A second connection portion is used to control whether the sensing electrode and the third electrode are connected when the knob is pressed.
7. The knob as described in claim 1, characterized in that, The knob contains only a single sensing electrode.
8. The knob as described in claim 1, characterized in that, At least one of the first reference voltage and the second reference voltage is a ground voltage.
9. The knob as claimed in claim 1, characterized in that, The first common electrode is coupled to a common electrode ring, and the sensing electrode is coupled to a sensing electrode ring. A connecting post is provided on the sensing electrode ring, and the connecting post is electrically connected to the sensing electrode ring.
10. The knob as claimed in claim 9, characterized in that, When the knob is rotated to a first angle, the common electrode ring contacts the connecting post and is electrically connected to the sensing electrode ring. When the knob is rotated to a second angle, the common electrode ring does not contact the connecting post.
11. The knob as claimed in claim 9, characterized in that, When the knob is rotated, the sensing electrode ring is fixed to the touchscreen, while the common electrode ring rotates with the knob.
12. The knob as claimed in claim 9, characterized in that, When the knob is rotated, the common electrode ring is fixed to the touch screen, while the sensing electrode ring rotates with the knob.
13. A sensing circuit coupled to a knob, characterized in that, The sensing circuit includes: A receiving circuit for receiving a signal change from the knob; and A processing circuit, coupled to the receiving circuit, is used to determine the rotation direction of the knob based on the change in the signal. The signal change is received by a first touch sensing unit that is aligned with and coupled to a sensing electrode of the knob; The signal change is generated based on whether the sensing electrode is connected to a first common electrode and a second common electrode in the knob.
14. The sensing circuit as described in claim 13, characterized in that, The knob contains only a single sensing electrode.
15. The sensing circuit as described in claim 13, characterized in that, The second touch sensing unit corresponding to the first common electrode and the third touch sensing unit corresponding to the second common electrode are respectively given a first reference voltage and a second reference voltage to generate the signal change.
16. The sensing circuit as described in claim 15, characterized in that, At least one of the first reference voltage and the second reference voltage is a ground voltage.
17. The sensing circuit as claimed in claim 15, characterized in that, At least one of the first reference voltage and the second reference voltage originates from a touch object that operates the knob.
18. The sensing circuit as claimed in claim 13, characterized in that, The processing circuit also determines whether the knob has been pressed based on the change in the signal.