Touch device based on optical sensing pressure sensing structure

Abstract

The invention discloses a touch device based on a light sensing pressure sensing structure. The touch device comprises a supporting frame, a light source, a pressure-sensitive film and a photoelectric sensor. The supporting frame comprises a bearing plate, a bottom plate and a connecting piece connected between the bearing plate and the bottom plate. The bearing plate is positioned above the bottom plate and is parallel to the bottom plate; the light source is arranged on the lower surface of the bearing plate; the at least two light sources are symmetrical about the connecting piece; the pressure-sensitive film and the photoelectric sensor are both arranged on the bottom plate and located below the light source, the light source makes contact with the pressure-sensitive film, and the pressure-sensitive film is located on the upper surface of the photoelectric sensor; light of the light source is received by the photoelectric sensor after penetrating through the pressure-sensitive film; the pressure-sensitive film is of a porous structure. When the pressure-bearing plate bears pressure, the pressure borne by the pressure-sensitive film below the pressure point is increased, the light transmittance of the pressure-sensitive film is increased, the light intensity received by the photoelectric sensor is increased, and the pressure point position and the pressure can be judged according to the light intensity received by the photoelectric sensor.

Description

Technical Field

[0001] The present invention belongs to the technical field of pressure sensing, and in particular relates to a touch control device based on a light sensing pressure sensing structure. Background Art

[0002] In existing terminal portable electronic devices such as mobile phones, computers, tablets, etc., mechanical buttons are mostly used for operation control, including power on and off, volume adjustment, and various specific functions. However, mechanical buttons can only switch between on and off states, and cannot achieve infinite adjustment functions; and after long-term use, the contacts of mechanical buttons may accumulate dust or oxidize, resulting in insensitive button response, affecting the user experience.

[0003] In addition, some electronic devices use capacitive buttons to control the device. Such capacitive buttons have no protruding physical parts and are more durable. They can also identify the touch position of the finger, thereby realizing more functions. However, capacitive buttons also have problems in practical applications: first, capacitive buttons require finger touch, so they are not suitable for use with gloves, and unclean or dirty buttons or user fingers will cause inaccurate capacitive sensing; second, capacitive buttons are complicated to install and calibrate. If they are not designed and installed properly, they may cause false touches or inability to respond correctly. Summary of the invention

[0004] The purpose of the present invention is to provide a pressure sensing structure based on optical sensing that can be used for touch control, aiming to solve the problems of single function of existing mechanical buttons and limited operation of capacitive touch control methods.

[0005] The present invention provides a touch control device based on a light sensing pressure sensing structure, comprising a support frame, a light source, a pressure sensitive film and a photoelectric sensor;

[0006] The support frame comprises a pressure-bearing plate, a bottom plate, and a connecting member connected between the pressure-bearing plate and the bottom plate; the pressure-bearing plate is located above the bottom plate and parallel to the bottom plate;

[0007] The light source is arranged on the lower surface of the pressure plate, away from the connecting column and adjacent to the edge of the pressure plate; there are at least two light sources, which are symmetrical about the connecting piece;

[0008] The pressure-sensitive film and the photoelectric sensor are both arranged on the bottom plate;

[0009] The pressure-sensitive film is a porous structure;

[0010] The number of light sources, pressure-sensitive films and photoelectric sensors is the same. The pressure-sensitive films and photoelectric sensors are all located below the light sources, and the light sources are in contact with the pressure-sensitive films. The pressure-sensitive films are located on the upper surface of the photoelectric sensors. The light from the light sources passes through the pressure-sensitive films and is received by the photoelectric sensors. Each light source, pressure-sensitive film and photoelectric sensor constitutes a set of pressure sensing structures.

[0011] The cross-sectional area of ​​the connecting member is much smaller than the surface area of ​​the pressure plate. The cross-sectional area of ​​the connecting member refers to the cross-sectional area parallel to the pressure plate, so that there is a larger gap between the pressure plate and the bottom plate to facilitate setting of multiple groups of pressure sensing structures.

[0012] The support frame has a high deformation modulus, and the pressure plate is similar to a cantilever beam structure. It will bend under pressure, but the bottom plate and connecting parts will not deform significantly.

[0013] The light source, pressure-sensitive film and photoelectric sensor form an optical path detection system. The light emitted by the light source passes through the pressure-sensitive film and is received and detected by the photoelectric sensor at the bottom. When the light passes through the pressure-sensitive film, it is diffusely reflected by the porous inside of the film. When the pressure on the pressure-sensitive film increases, the internal pore structure is compressed and becomes smaller, the diffuse reflection effect weakens, the transmittance of light increases, and the light intensity received by the photoelectric sensor becomes stronger. When the pressure on the pressure-sensitive film decreases, the pressure on the internal pore structure of the pressure-sensitive film decreases, the pore structure gradually recovers, the diffuse reflection effect increases, the transmittance of light decreases, and the light intensity received by the photoelectric sensor becomes weaker. Therefore, the pressure on the pressure plate is reflected by the change in the light intensity received by the photoelectric sensor.

[0014] Furthermore, the light source includes a light emitting device and a shell for encapsulating the light emitting device; the light emitting device is a laser diode; the pressure sensitive film is subjected to the pressure of the laser diode and has a pre-compression deformation. The pre-compression deformation refers to the initial pressure that the pressure sensitive film in the device of the present invention has been subjected to before the pressure plate is subjected to external force.

[0015] The shell is made of epoxy resin, and the receiving end of the photoelectric sensor is also encapsulated with epoxy resin; it has a high Young's modulus and good light transmittance, can withstand a certain pressure and will not weaken the light.

[0016] Furthermore, the surface of the pressure plate is a centrally symmetrical and axially symmetrical figure; the bottom plate has the same structure as the pressure plate, but is made of different materials. The connecting member connects the center of the pressure plate and the center of the bottom plate, and the connecting member is a cylinder or a prism.

[0017] Furthermore, the surface of the pressure plate is a rectangular structure, the shape of the bottom plate is the same as that of the pressure plate, the connecting piece passes through the center position of the pressure plate and the center position of the bottom plate, the connecting piece is a vertical plate or a cylinder, and the surface of the vertical plate is parallel to the short side direction of the pressure plate.

[0018] The laser diode is symmetrically arranged on the lower surface of the pressure plate and is adjacent to the short side of the pressure plate.

[0019] Furthermore, the surface of the pressure plate is a circular structure, the shape of the bottom plate is the same as that of the pressure plate, the connecting piece passes through the center position of the pressure plate and the center position of the bottom plate, and the connecting piece is a right prism or a cylinder; the laser diode is arranged on the lower surface of the pressure plate and is evenly distributed on the same circumference.

[0020] Furthermore, the touch control device based on the optical sensing pressure sensing structure of the present invention further includes a key cap, and the key cap is arranged on the upper surface of the pressure bearing plate;

[0021] The key cap comprises a pressing plate and a base located on the lower surface of the pressing plate; the base is connected to the upper surface of the pressure plate;

[0022] Furthermore, the pressing plate is a curved plate or a flat plate, and the curved plate is spherical or arched to match the surface of the pressure plate.

[0023] Furthermore, a groove is provided on the upper surface of the base plate, and the receiving end of the photoelectric sensor is located in the groove, and the height and bottom of the receiving end of the photoelectric sensor are flush with the upper surface of the base plate; the pressure-sensitive film is pasted on the upper surface of the base plate and covers above the groove, that is, covers the upper surface of the receiving end of the photoelectric sensor.

[0024] The emitting end of the laser diode is arranged opposite to the receiving end of the photoelectric sensor. The photoelectric sensor is used to receive the light signal and convert it into an electrical signal. The receiving end of the photoelectric sensor is longitudinally aligned with the laser emitting end of the laser diode to receive the laser through the pressure-sensitive film. The photoelectric sensor uses the electron excitation effect caused by the light-sensitive material to convert the light signal into an electrical signal, and then detects the change of light intensity.

[0025] Furthermore, the pressure-sensitive film includes a first PDMS film located in the upper layer, a porous film located in the middle layer, and a second PDMS film located in the lower layer; both the first PDMS film and the second PDMS film are transparent and have good light transmittance, and the Young's modulus of the first PDMS film and the second PDMS film is higher than that of the porous film in the middle; the porous film has a randomly distributed pore structure, and in the initial state, the pore structure has a divergent effect on the incident light, so that the film has a low light transmittance characteristic; under the action of pressure, the porous film is compressed, the pore structure is closed, and no longer has a divergent effect on the light, and the light transmittance of the film is improved. Therefore, the pressure-sensitive film has the characteristics of poor light transmittance in the initial state and improved light transmittance under pressure compression.

[0026] Furthermore, a touch device based on a light sensing pressure sensing structure of the present invention also includes an FPC board, on which electronic circuits are printed to power the laser diode, the laser diode is connected to the FPC board by welding, and the FPC board is connected to the lower surface of the pressure plate by gluing.

[0027] Furthermore, the keycaps and the supporting frame, as well as the supporting frame and the external terminal device are connected by welding or gluing, and the glue used for gluing has a high hardness after curing, ensuring that there is no relative movement between the bonding surfaces of the three. The photoelectric sensor of the present invention is electrically connected to the external terminal to output an electrical signal.

[0028] Beneficial effects: Compared with the prior art, the present invention has the following significant features:

[0029] 1. The present invention utilizes a pressure sensing structure composed of a laser diode, a photoelectric sensor and a pressure-sensitive film. The light intensity signal received by the photoelectric sensor increases as the applied pressure increases, and can accurately reflect the change in pressure.

[0030] 2. A pressure sensing structure is provided on each side of the connector of the present invention, which can accurately reflect the pressure acting on the pressure plate or the keycap, including: (1) when there is no pressure, the light transmittance of the pressure-sensitive films on both sides of the connector is the same, and the photoelectric sensor signals on both sides are reference values; (2) when one side of the pressure plate or the keycap is under pressure, the internal pore structure of the pressure-sensitive film on the force-bearing side is compressed and reduced or closed, the light transmittance is increased, and the photoelectric sensor signal is enhanced; the internal pore structure of the pressure-sensitive film on the other side is restored as the pressure is released, the light transmittance is reduced, and the photoelectric sensor signal is reduced; (3) when the middle part of the pressure plate or the keycap is under pressure, the pressure-sensitive films on both sides are subjected to the same force, the internal pore structure is compressed and closed, the light transmittance is increased, and the photoelectric sensor signal is enhanced to the same extent; (4) when both sides of the pressure plate or the keycap are under pressure, the pressure-sensitive films on both sides are subjected to force, the internal pore structure is compressed and closed, the light transmittance is increased, and the photoelectric sensor signal is enhanced, and the photoelectric sensor signal on the side with greater pressure is stronger.

[0031] The touch device based on the optical sensing pressure sensing structure provided by the present invention can detect the pressure size compared with the existing mechanical switch type buttons, thereby realizing more button functions; compared with capacitive buttons, it is simpler to install and debug, its performance is not easily affected by oil pollution or electromagnetic environment, and the user can operate the buttons regardless of whether he is wearing gloves or not. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The technical solution of the embodiment of the present invention is further described in detail below through the drawings and examples.

[0033] Figure 1 is a schematic diagram of a light sensing pressure sensing structure provided by the present invention;

[0034] Figure 2 It is a schematic diagram of the structure of a pressure-sensitive film capable of changing light transmittance under pressure according to the present invention;

[0035] Figure 3 Schematic diagram of the variable transmittance pressure-sensitive film, whose transmittance changes with pressure;

[0036] Figure 4 is a schematic diagram of the structural changes of the pressure sensing structure of the present invention under different pressures;

[0037] Among them, 1. keycaps; 2. supporting frame; 3. laser diode; 4. pressure-sensitive film; 5. photoelectric sensor; 6. FPC board; 41. first PDMS film; 42. porous film; 43. second PDMS film; 21. pressure plate; 22. bottom plate; 23. connector. DETAILED DESCRIPTION

[0038] In order to more clearly illustrate the technical solutions and advantages of the present invention, the present invention is further described in detail below in conjunction with the embodiments and drawings. It should be understood that the drawings described here are only some embodiments of the present application and are not intended to limit the present invention.

[0039] Embodiment 1

[0040] The present invention proposes a touch control device based on a light sensing pressure sensing structure, such as Figure 1 As shown, it includes a support frame 2, a laser diode 3, a pressure-sensitive film 4 and a photoelectric sensor 5; the pressure-sensitive film 4 is a porous structure;

[0041] The support frame 2 includes a pressure plate 21, a bottom plate 22, and a connecting member 23 connected between the pressure plate 21 and the bottom plate 22; the pressure plate 21 is located above the bottom plate 22 and is parallel to the bottom plate 22;

[0042] The laser diode 3 is arranged on the lower surface of the pressure plate 21 and is adjacent to the edge of the pressure plate 21; there are at least two laser diodes 3 and they are symmetrical about the connecting piece 23; specifically, the laser diode 3 is connected to the FPC board 6 by welding, and the FPC board 6 is glued to the lower surface of the pressure plate 21 for supplying power to the laser diode 3.

[0043] The pressure-sensitive film 4 and the photoelectric sensor 5 are both arranged on the bottom plate 22; the number of laser diodes 3, pressure-sensitive films 4 and photoelectric sensors 5 is the same and they correspond one to one, and each group of light sources, pressure-sensitive films 4 and photoelectric sensors 5 constitutes a group of pressure sensing structures; the pressure-sensitive film 4 and the photoelectric sensor 5 are both located below the laser diode 3, the laser diode 3 is in contact with the pressure-sensitive film 4, and there is a certain pressure on the laser diode 3, and the pressure-sensitive film 4 is located on the upper surface of the photoelectric sensor 5; the laser emission direction is vertically downward, and the light of the laser diode 3 is received by the photoelectric sensor 5 after passing through the pressure-sensitive film 4, and the photoelectric sensor 5 converts the optical signal into an electrical signal to reflect the change of light intensity.

[0044] The pressure-bearing plate 21 has a relatively high deformation modulus. The pressure-bearing plate 21 is similar to a cantilever beam structure and will bend and deform under pressure, while the bottom plate 22 and the connecting member 23 will not be significantly deformed.

[0045] The sensing principle of the pressure sensing structure is: when the pressure plate 21 is not under stress, the gap between the laser diode 3 and the photoelectric sensor 5 is slightly smaller than the thickness of the pressure-sensitive film 4. Therefore, the pressure-sensitive film 4 is squeezed in the initial state and undergoes pre-compression deformation. The hollow structure inside the pressure-sensitive film 4 is partially closed under the squeeze. Compared with the pressure-sensitive film 4 without deformation, the pressure-sensitive film 4 with pre-compression deformation has higher transmittance, and the light intensity loss of the laser after passing through the pressure-sensitive film 4 is small. At this time, the light intensity received by the photoelectric sensor 5 is the reference value.

[0046] When the pressure plate 21 is subjected to pressure, the compression deformation of the pressure-sensitive film 4 is further increased under the squeezing of the laser diode 3 and the photoelectric sensor 5, the internal porous structure of the pressure-sensitive film 4 is closed, the overall light transmittance of the pressure-sensitive film 4 is improved, and the light intensity received by the photoelectric sensor 5 is increased compared to the initial state, and the converted electrical signal increases, thereby reflecting the increase in pressure received by the pressure plate 21 of the present invention.

[0047] When the pressure on the pressure plate 21 decreases, the squeezing force of the laser diode 3 and the photoelectric sensor 5 on the pressure-sensitive film 4 decreases, the internal pore structure of the pressure-sensitive film 4 opens, the overall light transmittance of the pressure-sensitive film 4 decreases, and the light intensity received by the photoelectric sensor 5 decreases significantly. The light intensity received by the photoelectric sensor 5 is small, thereby reflecting that the pressure received by the pressure sensor is reduced.

[0048] When the pressure plate 21 is under pressure on one side, the pressure-sensitive film 4 on both sides of the connecting member 23 is under different pressure conditions, and the generated photoelectric signal changes are also different; the pressure-bearing end of the pressure plate 21 moves downward, and the other end opposite to the pressure-bearing end moves upward, the pressure-sensitive film 4 below the pressure-bearing end is squeezed, the porous structure inside the pressure-sensitive film 4 becomes smaller, the overall light transmittance of the pressure-sensitive film 4 is improved, the light intensity received by the photoelectric sensor 5 is greater than the reference value, and the converted electrical signal increases, thereby reflecting that the pressure on the pressure plate 21 where the laser diode 3 is located increases; for the upward moving end of the pressure plate 21, the degree of squeezing of the pressure-sensitive film 4 below is less than the initial pressure, the internal pore structure of the pressure-sensitive film 4 opens, the overall light transmittance of the pressure-sensitive film 4 decreases, and the light intensity received by the photoelectric sensor 5 is less than the reference value.

[0049] When the pressure plate 21 is subjected to multiple downward forces on all sides, since the pressure plate 21 has a higher deformation modulus, the multiple pressure positions on all sides of the pressure plate 21 will move downward, and the light received by the corresponding photoelectric sensors 5 below the pressure positions will change. The pressed position will be mapped according to the change in the photoelectric signal of the photoelectric sensor 5, thereby reflecting the position where the pressure acts and realizing more button functions.

[0050] Embodiment 2

[0051] A touch device based on a light sensing pressure sensing structure is described in Example 1, wherein the surface of the pressure plate 21 is a rectangular structure, the shape of the bottom plate 22 is the same as that of the pressure plate 21, and the connecting member 23 passes through the center position of the pressure plate 21 and the center position of the bottom plate 22. The connecting member 23 is a vertical plate or a cylinder, and the surface where the vertical plate is located is parallel to the short side direction of the pressure plate 21.

[0052] The laser diode 3 is symmetrically arranged on the lower surface of the pressure plate 21 and is adjacent to the short side of the pressure plate 21 .

[0053] Embodiment 3

[0054] A touch device based on an optical sensing pressure sensing structure in the first embodiment, wherein the surface of the pressure plate 21 is a circular structure, the shape of the bottom plate 22 is the same as that of the pressure plate 21, the connecting member 23 passes through the center position of the pressure plate 21 and the center position of the bottom plate 22, and the connecting member 23 is a regular prism or a cylinder;

[0055] The laser diodes 3 are arranged on the lower surface of the pressure plate 21 and are evenly distributed on the same circumference, so as to facilitate testing of multiple pressure points.

[0056] Embodiment 4

[0057] Based on the touch control device based on the optical sensing pressure sensing structure in the first embodiment, the touch control device based on the optical sensing pressure sensing structure of the present invention further includes a key cap 1, which is detachably arranged on the upper surface of the pressure plate 21; the key cap 1 includes a pressing plate and a base located on the lower surface of the pressing plate; the base is connected to the upper surface of the pressure plate 21;

[0058] The key cap 1 is made of hard material and will not deform. The key cap 1 is a physical interface for the user to interact with the device. The surface of the key cap 1 is subjected to the user's touch, pressing and sliding actions, and transmits the pressure to the supporting frame 2 below.

[0059] The pressure-sensitive film 4 has a three-layer structure. Figure 2 As shown, the first PDMS transparent film is located at the top, the second PDMS transparent film is located at the bottom, and the porous film 42 with a pore microstructure is located in the middle layer. The thickness of the first PDMS transparent film, the second PDMS transparent film and the porous film 42 are the same, and the Young's modulus of the PDMS film is higher than that of the porous film 42. Therefore, when the pressure-sensitive film 4 is subjected to pressure, the first PDMS transparent film and the second PDMS transparent film can encapsulate and protect the middle porous film 42.

[0060] Under the action of pressure, the light transmittance of the pressure-sensitive film 4 will change. The principle of light transmittance change is as follows: Figure 3As shown, the first PDMS transparent film and the second PDMS transparent film are relatively hard and transparent, and the middle porous film 42 itself is made of transparent material, and the dispersed porous structure inside produces diffuse reflection on the light, so that the light entering the porous film 42 is irregularly divergent, so that the light penetrating the pressure-sensitive film 4 to reach the bottom photoelectric sensor 5 has a loss in light intensity compared to the incident light, and this loss is largely caused by the middle porous film 42. Figure 3 (b) is the pressure-sensitive film 4 with pre-compression deformation in the present invention, that is, the initial state of the pressure-sensitive film 4 in the present invention. The light is emitted from the laser diode 3, passes through the first PDMS film 41 and enters the middle porous film 42. The pore structure inside the porous film 42 causes the incident light to be diffusely reflected. Part of the light passes through the porous film 42 and the second PDMS film 43 and is received by the bottom photoelectric sensor 5. At this time, the light intensity detected by the photoelectric sensor 5 is the reference value of the device of the present invention. When the pressure applied to the first PDMS film 41 decreases, as shown in FIG. Figure 3 As shown in (a), the pore structure inside the porous film 42 is released, making the light transmittance lower, so that the intensity of the transmitted light received by the photoelectric sensor 5 is further reduced. At this time, the signal of the photoelectric sensor 5 decreases, reflecting that the pressure applied to the first PDMS film 41 decreases; when the pressure applied to the first PDMS film 41 increases, as shown in Figure 3 As shown in (c), the pore structure inside the porous film 42 is further compressed, the light blocked by diffuse reflection is reduced, and the light transmittance is increased, thereby increasing the light intensity signal detected by the photoelectric sensor 5. Furthermore, when the pressure is further increased, the pore structure is closed, so that the light can pass through the pressure-sensitive film 4 to the photoelectric sensor 5 without being hindered by the pore structure, and the generated light intensity signal is the maximum. In summary, the optical path composed of the laser diode 3-pressure-sensitive film 4-photoelectric sensor 5 can detect the magnitude of the applied pressure, which is specifically manifested as follows: when the pressure decreases, the light intensity signal detected by the photoelectric sensor 5 decreases; when the pressure increases, the light intensity signal detected by the photoelectric sensor 5 increases.

[0061] Furthermore, based on the above-mentioned light-pressure signal sensing principle, the basic pressure sensing principle of the pressure sensing structure described in the present invention is: when the keycap 1 is subjected to pressure, the pressure-bearing plate 21 on the top of the support frame 2 will undergo corresponding deformation, causing the pressure-sensitive film 4 to produce a corresponding compression / release effect, so that the photoelectric sensor 5 detects the light intensity signal to reflect the magnitude of the force on the pressure side.

[0062] Specifically, under the action of pressure, the key cap 1 and the support frame 2 will produce different effects. Figure 4As shown, when the key cap 1 is not subjected to force, the cantilever beam at the top of the support frame 2 remains horizontal; when pressure acts on the left side of the key cap 1, the pressure plate 21 bends downward, causing the gap between the pressure plate 21 and the bottom plate 22 below the pressure position to be compressed, and the other side of the cantilever beam is raised under the action of the key cap 1 connected to the key to increase the gap; when the pressing position is in the middle of the key, both sides of the cantilever beam will bend downward and the bending amplitude is the same, and the gaps on both sides will decrease at the same time; when pressure acts on both sides of the key cap 1, both sides of the cantilever beam will bend downward, and the bending amplitude is positively correlated with the magnitude of the pressure. In summary, when pressure acts on the key cap 1, according to different effects, the gap between the cantilever beam and the bottom of the support frame 2 changes, and the extrusion force of the laser diode 3 and the photoelectric sensor 5 installed on the support frame 2 on the pressure-sensitive film 4 also changes, thereby changing the light transmittance of the film, causing the photoelectric signal to change and thus reflecting the applied force.

[0063] Under any single pressing force, the photoelectric sensor 5 below the pressure point and the photoelectric sensor 5 arranged opposite to the pressure point will generate corresponding signal outputs. By analyzing the signal, the size of the pressure and the point of action can be quantitatively analyzed.

[0064] Specifically, taking position analysis as an example, when the same force acts on different points on the keycap 1, the light intensity signal on the pressure acting side is larger and greater than the reference value, and the light intensity signal on the other side is smaller and less than the reference value; when the pressing position gradually moves toward the center of the key, the light intensity signal on the pressure acting side decreases but remains above the reference value, while the light intensity signal on the other side also gradually increases and approaches the reference value; when the pressure acts on the center point, the light intensity signals on both sides are the same; when the pressure acting point exceeds the center point, the photoelectric signal on the initial side decreases, while the photoelectric signal on the other side increases. The pressure acting position can be determined by the ratio of the change in the photoelectric signals on both sides to the reference signal during this process.

[0065] Or, taking the pressure analysis as an example, when different pressures are applied to the same point on the keycap 1, the photoelectric signals on the pressure-applying side and the other side respectively produce an increase / decrease effect. When the pressure increases, the increase / decrease effect produced by the photoelectric signals on both sides increases. Therefore, the pressure applied to the keycap 1 can be determined by the amplitude of the change between the photoelectric signals on both sides and the reference value. In particular, when pressure is applied to the center point of the keycap 1, the photoelectric signals on both sides change in the same amount, and the greater the pressure, the greater the change, thereby reflecting the pressure applied to the center point.

[0066] The mapping relationship between the magnitude of the pressure action can be established through the amplitude of the signal changes on both sides, and the mapping relationship between the pressure action position can be established through the ratio of the signal changes on both sides. The magnitude and position information of the random force can be detected by combining the above two mapping relationships.

[0067] Under constant pressure, when the pressure point moves from one side of the key cap 1 to the other, the photoelectric signal changes continuously during this process. Therefore, combined with the above-mentioned mapping relationship between pressure size and position, the real-time position information of the pressing force during the movement on the key cap 1 can be calculated, thereby detecting the key sliding operation.

[0068] The above examples are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A touch device based on a pressure sensing structure, characterized in that: include: A supporting frame (2), a light source, a pressure-sensitive film (4) and a photoelectric sensor (5); The support frame (2) comprises a pressure-bearing plate (21), a bottom plate (22), and a connecting member (23) connected between the pressure-bearing plate (21) and the bottom plate (22); the pressure-bearing plate (21) is located above the bottom plate (22) and is parallel to the bottom plate (22); The light source is arranged on the lower surface of the pressure plate (21); there are at least two light sources, which are symmetrical about the connecting piece (23); The pressure-sensitive film (4) and the photoelectric sensor (5) are both arranged on the bottom plate (22); The pressure-sensitive film (4) and the photoelectric sensor (5) are both located below the light source, and the light source is in contact with the pressure-sensitive film (4). The pressure-sensitive film (4) is located on the upper surface of the photoelectric sensor (5). Light from the light source is received by the photoelectric sensor (5) after passing through the pressure-sensitive film (4). The pressure-sensitive film (4) has a porous structure.

2. A touch control device based on a pressure sensing structure according to claim 1, characterized in that: The light source comprises a light emitting device and a housing for encapsulating the light emitting device; The light emitting device is a laser diode (3); The shell exerts a pre-pressure on the pressure-sensitive film (4), so that the pressure-sensitive film (4) has a pre-compression deformation.

3. The touch control device based on the pressure sensing structure according to claim 1, characterized in that: The surface of the pressure plate (21) is a centrally symmetrical and axially symmetrical figure; The bottom plate (22) has the same structure as the pressure plate (21); The connecting member (23) connects the center of the pressure plate (21) and the center of the bottom plate (22); The connecting piece (23) is a cylinder or a prism.

4. The touch control device based on the pressure sensing structure according to claim 1, characterized in that: The surface of the pressure plate (21) is a rectangular structure, the shape of the bottom plate (22) is the same as that of the pressure plate (21), the connecting member (23) passes through the center position of the pressure plate (21) and the center position of the bottom plate (22), the connecting member (23) is a vertical plate or a cylinder, and the surface where the vertical plate is located is parallel to the short side direction of the pressure plate (21); The laser diode (3) is symmetrically arranged on the lower surface of the pressure-bearing plate (21) and is adjacent to the short side of the pressure-bearing plate (21).

5. The touch control device based on the pressure sensing structure according to claim 1, characterized in that: The surface of the pressure plate (21) is a circular structure, the shape of the bottom plate (22) is the same as that of the pressure plate (21), the connecting piece (23) passes through the center position of the pressure plate (21) and the center position of the bottom plate (22), and the connecting piece (23) is a regular prism or a cylinder; The laser diodes (3) are arranged on the lower surface of the pressure-bearing plate (21) and are evenly distributed on the same circumference.

6. The touch control device based on the pressure sensing structure according to claim 1, characterized in that: It also includes a key cap (1), wherein the key cap (1) is arranged on the upper surface of the pressure bearing plate (21); The key cap (1) comprises a pressing plate and a base located on the lower surface of the pressing plate; the base is connected to the upper surface of the pressure-bearing plate (21).

7. A touch control device based on a pressure sensing structure according to claim 6, characterized in that: The pressing plate is a curved plate or a flat plate, and the curved plate is spherical or arched.

8. The touch control device based on the pressure sensing structure according to claim 1, characterized in that: The upper surface of the bottom plate (22) is provided with a groove, the receiving end of the photoelectric sensor (5) is located in the groove, and the height of the receiving end of the photoelectric sensor (5) is flush with the upper surface of the bottom plate (22); The pressure-sensitive film (4) is adhered to the upper surface of the bottom plate (22) and covers the groove, that is, covers the upper surface of the receiving end of the photoelectric sensor (5).

9. The touch control device based on the pressure sensing structure according to claim 1, characterized in that: The pressure-sensitive film (4) comprises a first PDMS film (41) located at an upper layer, a porous film (42) located at a middle layer, and a second PDMS film (43) located at a lower layer.

10. The touch control device based on the pressure sensing structure according to claim 1, characterized in that: It also includes an FPC board (6) connected to the laser diode (3) and used to supply power to the laser diode (3); the FPC board (6) is connected to the lower surface of the pressure-bearing plate (21).

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