Rebound tonometer and intraocular pressure measurement method

Abstract

The application discloses a rebound tonometer and an intraocular pressure measuring method. The tonometer comprises a tonometer main body, a power adjusting module, and a controller. The tonometer main body comprises a probe, a driving coil and a measuring coil. The controller is configured to adjust a first excitation voltage through the power adjusting module, acquire a first corresponding relationship, determine an actual parameter value by using the first corresponding relationship, calculate a correction voltage by using a difference between the actual parameter value and a target parameter value when the difference is greater than a preset threshold, correct the first excitation voltage according to the correction voltage to obtain a target excitation voltage, determine the first excitation voltage as the target excitation voltage when the difference between the actual parameter value and the target parameter value is less than or equal to the preset threshold, and measure the intraocular pressure of a to-be-measured object according to the target excitation voltage to obtain an output intraocular pressure value. According to the application, the accuracy of the intraocular pressure measurement can be improved, and the user can have a more comfortable use experience.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of electronic devices, and particularly relates to a rebound tonometer and an intraocular pressure measurement method. BACKGROUND

[0002] Due to the acceleration of modern life rhythm and the popularity of electronic products, eye health problems are increasingly prominent, and various eye diseases occur frequently. Intraocular pressure, i.e., eye pressure, is an important indicator for measuring the health status of the eye. In order to effectively monitor and prevent the development of eye diseases, especially for some diseases closely related to abnormal eye pressure, regular eye pressure measurement plays a crucial role in the diagnosis and treatment of various eye diseases. In the related art, the eye pressure can be measured by a tonometer. Moreover, the performance and accuracy of the tonometer directly affect the diagnosis results and treatment effects.

[0003] The rebound tonometer provides a certain initial kinetic energy for the probe through the driving coil, so that the probe hits the cornea, and the displacement and acceleration of the probe are recorded to calculate the eye pressure value. For different users' corneas, the feeling of the impact degree is different. If the impact degree is too large, it is inevitable to cause damage to the cornea; if the impact degree is too small, accurate measurement values cannot be obtained. Therefore, the control of the impact degree is a difficulty.

[0004] In addition, in order to avoid the error of single measurement, when measuring the eye pressure, the measurement value is not directly given for single measurement, but multiple repeated measurements are adopted, and the multiple measurement results are calculated to determine the eye pressure value of the patient. For example, a measurement period includes six repeated measurements, and the eye pressure value reading is given only after the six measurements are completed. However, among the multiple measurement data in the same measurement period, assuming that the error of one or several times is large, even if the final reading is the result of processing the multiple measurement values, due to the influence of the measurement with large error, a large deviation may still occur, and the measurement result cannot correctly represent the actual eye pressure condition of the patient.

[0005] Therefore, how to ensure the accuracy of the eye pressure value in the eye pressure measurement and take into account the user's experience of the impact degree has become a technical problem to be solved in the industry. SUMMARY

[0006] The embodiments of the present application provide a rebound tonometer and an intraocular pressure measurement method, which can improve the accuracy of the intraocular pressure measurement and bring a more comfortable user experience.

[0007] In a first aspect, the embodiments of the present application provide a rebound tonometer, comprising: a tonometer main body, the tonometer main body comprising a probe, a driving coil and a measuring coil, wherein the driving coil and the measuring coil partially surround the probe, the driving coil is used to drive the probe to emit and generate displacement along the extension direction of the probe, and the measuring coil is used to detect the motion state of the probe; a power adjusting module, the power adjusting module being electrically connected with the controller and the driving coil respectively; a controller, the controller being electrically connected with the measuring coil, and being used to perform the following operations: adjusting a first excitation voltage input to the driving coil by the power adjusting module, so that the probe emits along the extension direction of the probe under the driving of the first excitation voltage; obtaining a first correspondence between a first measurement voltage in the measuring coil and time in the process of rebounding in the opposite direction after the probe hits the cornea; determining an actual measurement parameter value of the probe at the moment of hitting the cornea by the controller using the first correspondence; in the case that the difference between the actual measurement parameter value and a target parameter value is greater than a preset threshold, calculating a correction voltage using the difference; correcting the first excitation voltage according to the correction voltage to obtain a target excitation voltage; in the case that the difference between the actual measurement parameter value and the target parameter value is less than or equal to the preset threshold, the first excitation voltage is the target excitation voltage; and measuring the intraocular pressure of the object to be measured according to the target excitation voltage to obtain an output intraocular pressure value in the same measurement period.

[0008] In a possible implementation of the first aspect, the rebound tonometer further comprises: a voltage conversion device comprising a power input end, a first input end, a first output end and a feedback end; a first voltage regulating module connected between the first output end and the feedback end; a filter module, one end of the filter module being connected with the first output end, and the other end of the filter module being connected with the driving coil; wherein the first end of the power adjusting module is connected with the controller, and the second end of the power adjusting module is connected with the first voltage regulating module; and a power supply connected with the power input end of the voltage conversion device and the controller respectively.

[0009] In a possible implementation of the first aspect, the rebound tonometer further comprises a first switch device and a second switch device, the first switch device being located between the filter module and the driving coil and being connected with the controller, and the second switch device being located between the filter module and the measuring coil and being connected with the controller.

[0010] In a possible implementation of the first aspect, the rebound tonometer further comprises a first voltage dividing resistor and a second voltage dividing resistor, wherein the first voltage dividing resistor is connected between the first switch device and the driving coil, and the second voltage dividing resistor is connected between the second switch device and the measuring coil.

[0011] In a possible implementation of the first aspect, the power adjustment module comprises: a second voltage adjustment module, a first end of the second voltage adjustment module being connected to the controller, and a second end of the second voltage adjustment module being connected to the first voltage adjustment module; or a second excitation voltage input module, a first end of the second excitation voltage input module being connected to the controller, and a second end of the second excitation voltage input module being connected to the first voltage adjustment module.

[0012] In a possible implementation of the first aspect, the second voltage adjustment module comprises at least one of: a variable resistor, a control end of the variable resistor being connected to the controller, a first end of the variable resistor being connected to the first voltage adjustment module, and a second end of the variable resistor being grounded; or a plurality of series resistors, each of the series resistors being connected to the first voltage adjustment module and being connected to the controller through a switch device, so as to control whether the corresponding resistor is connected to the second voltage adjustment module.

[0013] In the second aspect, the embodiments of the present application provide a method for measuring intraocular pressure, and the method is applied to the first aspect or any possible implementation of the first aspect. The method comprises: adjusting a first excitation voltage input to a driving coil by a power adjustment module, so that a probe is emitted along a probe extension direction under the driving of the first excitation voltage; obtaining, by a controller, a first correspondence between a first measurement voltage in a measurement coil and time in a process in which the probe rebounds in a reverse direction after hitting a cornea; determining, by the first correspondence, a measured parameter value of the probe at a moment of hitting the cornea; in a case where a difference between the measured parameter value and a target parameter value is greater than a preset threshold, calculating a correction voltage by using the difference; correcting the first excitation voltage according to the correction voltage to obtain a target excitation voltage; in a case where the difference between the measured parameter value and the target parameter value recommended by a system is less than or equal to the preset threshold, the first excitation voltage is the target excitation voltage; and measuring, according to the target excitation voltage, an intraocular pressure of a to-be-measured object to obtain a final measurement result in a same measurement period.

[0014] In a possible implementation of the second aspect, the intraocular pressure of the subject is measured according to the target excitation voltage to obtain a final measurement result of the same measurement period, including: adjusting the voltage input to the drive coil to the target excitation voltage by the power adjustment module; in the case where the first excitation voltage is determined to be the target excitation voltage, calculating the intraocular pressure of the subject by using the measured parameter value to obtain a single intraocular pressure measurement result, and recording the measurement result as the first measurement result of the same measurement period; exciting the drive coil according to the target excitation voltage to make the probe emit along the probe extension direction; obtaining the target correspondence between the second measurement voltage in the measurement coil and the time during the process of the probe rebounding in the opposite direction after hitting the cornea by the controller; calculating the energy value of the probe at the moment of hitting the cornea according to the target correspondence; calculating the intraocular pressure of the subject by using the energy value at the moment of hitting to obtain a single measurement result; determining whether N measurements in the same measurement period are completed, if yes, calculating the final measurement result according to the N single measurement results in the same measurement period; if not, returning to exciting the drive coil according to the target excitation voltage until N measurements in the same measurement period are completed.

[0015] In a possible implementation of the second aspect, before exciting the drive coil according to the target excitation voltage to make the probe emit along the probe extension direction, the method further includes: in the case where the first excitation voltage is determined to be the target excitation voltage, calculating the intraocular pressure of the subject by using the measured parameter value to obtain a single intraocular pressure measurement result, and recording the measurement result as the first single measurement result of the same measurement period.

[0016] In a possible implementation of the second aspect, the measured parameter value includes a measured energy value corresponding to an energy parameter, the target parameter value includes a target energy value corresponding to the energy parameter, the target parameter value is related to the human-machine distance and the corneal sensitivity; the first excitation voltage represents that the drive coil emits the probe at the first time under the excitation of the first excitation voltage, and the probe hits the cornea at the target energy value after passing through a preset distance and within a second time; the measured parameter value of the probe at the moment of hitting the cornea is determined by the first correspondence, including: integrating the first measurement voltage corresponding to the first time to the second time by the first correspondence to determine the first displacement of the probe, the first displacement representing the distance moved by the probe within the first time to the second time; determining the second correspondence between the energy and the displacement by the first correspondence between the first measurement voltage and the time; according to the second correspondence, the energy value corresponding to the first distance is determined as the measured energy value of the probe when hitting the cornea.

[0017] In a possible implementation of the second aspect, the measured parameter value includes a measured speed value corresponding to the speed parameter, and the target parameter value includes a target speed value corresponding to the speed parameter; the first excitation voltage is used to drive the coil to emit the probe at the first time, and the probe impacts the cornea at the target speed value within the preset distance and within the second time; the measured parameter value of the probe at the moment of impacting the cornea is determined by the first corresponding relationship, including: the first displacement of the probe is determined by integrating the first measurement voltage corresponding to the time period between the first time and the second time according to the first corresponding relationship, and the first displacement represents the distance moved by the probe within the first time and the second time; the second corresponding relationship between the energy and the displacement is determined by the first corresponding relationship between the first measurement voltage and the time; the third corresponding relationship between the speed and the displacement is determined by the second corresponding relationship between the energy and the displacement and the kinetic energy theorem; and the speed value corresponding to the first distance is determined as the measured speed value of the probe at the moment of impacting the cornea according to the third corresponding relationship.

[0018] In a possible implementation of the second aspect, the second corresponding relationship between the energy and the displacement is determined by the first corresponding relationship between the first measurement voltage and the time, including: the fourth corresponding relationship between the driving force and the displacement is determined by the first corresponding relationship between the first measurement voltage and the time and the force relationship of the probe; and the second corresponding relationship between the energy and the displacement is determined by the fourth corresponding relationship between the driving force and the displacement.

[0019] In a possible implementation of the second aspect, when the difference between the measured parameter value and the target parameter value is greater than the preset threshold, the correction voltage is calculated by using the difference, including: an energy difference between the measured energy value and the target energy value is calculated; a distance difference between the first displacement and the preset distance is calculated; the correction driving force is calculated by using the distance difference and the energy difference; and the correction voltage corresponding to the correction driving force is determined by using the magnetic energy formula.

[0020] In a possible implementation of the second aspect, when the difference between the measured parameter value and the target parameter value is greater than the preset threshold, the correction voltage is calculated by using the difference, including: a speed difference between the measured speed value and the target speed value is calculated; the correction energy is calculated by using the speed difference; a distance difference between the first displacement and the preset distance is calculated; the correction driving force is calculated by using the distance difference and the correction energy; and the correction voltage corresponding to the correction driving force is determined by using the magnetic energy formula.

[0021] In a possible implementation of the second aspect, before the first excitation voltage of the input driving coil is adjusted by the power adjustment module so that the probe is emitted along the probe extension direction under the driving of the first excitation voltage, the method includes: the second excitation voltage is output to the measurement coil by the controller so that the probe is pulled back to the initial position along the probe extension direction.

[0022] The tonometer provided by the embodiment of the present application comprises a tonometer main body, a power adjusting module and a controller. The controller can control the power adjusting module to output a first excitation voltage to a driving coil in the tonometer main body, so that a probe in the tonometer main body is driven by the first excitation voltage to hit the cornea of a to-be-measured object. After the probe hits the cornea of the to-be-measured object, the probe rebounds, at this time, the controller can determine an actual measurement parameter value of the probe when hitting the cornea according to a first correspondence between a first measurement voltage generated in a measurement coil in the tonometer main body and time. By calculating the difference between the actual measurement parameter value actually generated by the probe when hitting the cornea of the to-be-measured object and a target parameter value, it can be determined whether the size of the first excitation voltage needs to be adjusted. In the case where it is determined that the difference is greater than a preset threshold, it can be determined that the probe driven according to the first excitation voltage will cause an uncomfortable experience to the user or is not conducive to the accuracy of tonometry. Therefore, the voltage value of the first excitation voltage that needs to be adjusted can be determined according to the difference, that is, a correction voltage is calculated. Further, the first excitation voltage can be corrected by the correction voltage to obtain a target excitation voltage. The above process can be regarded as a trial hitting period of the user within the safety interval of the factory setting. Through the trial hitting period, the best excitation voltage suitable for the sensitivity of the cornea is found. After the best excitation voltage is found, the formal measurement period is started, which can ensure the consistency of the probe excitation voltage under the same man-machine distance, ensure the relative accuracy of each measurement, and finally ensure the accuracy of the intraocular pressure value given by the system after the same measurement period ends. Therefore, in the case of measuring the intraocular pressure according to the target excitation voltage, the intraocular pressure can be accurately measured, and the user experience is improved. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required to be used in the embodiments of the present application will be briefly introduced. Those skilled in the art can obtain other drawings according to these drawings without creating any creative labor.

[0024] Figure 1 An architecture schematic diagram of a rebound tonometer provided by an embodiment of the present application is shown;

[0025] Figure 2 A circuit architecture schematic diagram of a rebound tonometer provided by another embodiment of the present application is shown;

[0026] Figure 3 A circuit architecture schematic diagram of a rebound tonometer provided by another embodiment of the present application is shown;

[0027] Figure 4 A circuit schematic diagram of a second voltage adjusting module provided by an embodiment of the present application is shown;

[0028] Figure 5 a circuit schematic diagram of a second voltage regulating module provided by another embodiment of the present application is shown;

[0029] Figure 6 a circuit schematic diagram of a second excitation voltage input module provided by an embodiment of the present application is shown;

[0030] Figure 7 a circuit schematic diagram of a second excitation voltage input module provided by another embodiment of the present application is shown;

[0031] Figure 8 a flow chart of an intraocular pressure testing method provided by an embodiment of the present application is shown;

[0032] Figure 9 a schematic diagram of a fourth correspondence provided by an embodiment of the present application is shown;

[0033] Figure 10 a schematic diagram of a second correspondence provided by an embodiment of the present application is shown;

[0034] Figure 11 a schematic diagram of a third correspondence provided by an embodiment of the present application is shown. DETAILED DESCRIPTION

[0035] The features and exemplary embodiments of the various aspects of the present application will be described in detail below with reference to the drawings. To make the purpose, technical solutions and advantages of the present application more clear, the present application will be further described in detail below with reference to the drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, but not to limit the present application. The present application can be implemented without some of the specific details by those skilled in the art. The following description of the embodiments is only to provide a better understanding of the present application by showing examples of the present application.

[0036] It should be noted that, in this document, relational terms such as first and second, and the like, are used solely to distinguish one entity or action from another entity or action, without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without more limitations, an element preceded by "comprises... a" does not, without more constraints, foreclose the existence of additional identical elements in the process, method, article, or apparatus that comprises the element.

[0037] The inventor has found that for a single measurement, the probe is ejected after being charged by the drive coil, and the energy loss caused by friction and other resistance in the forward path determines the impact force on the cornea. Therefore, as long as the residual energy of each measurement at the moment of impact on the cornea is consistent within the same measurement period, the impact force can be ensured to be consistent, and at the same time, the consistency of the intraocular pressure value of each measurement within the same measurement period can be ensured. The "same measurement period" described herein is to keep the distance between the tonometer and the cornea unchanged after the user determines the distance.

[0038] To this end, the embodiments of the present application provide a rebound tonometer and an intraocular pressure measurement method. First, the rebound tonometer provided by the embodiments of the present application will be introduced in combination with the following embodiments. The "human-machine distance" in the following refers to the distance between the cornea of a person and the proximal end of the tonometer main body (excluding the probe). The "final measurement result" in the following refers to the intraocular pressure value calculated and output to the user at the end of the same measurement period, and thus is the same concept as the output intraocular pressure value of the same measurement period.

[0039] For ease of understanding, in the embodiments of the present application, the architecture of the rebound tonometer is first described, and then the functions thereof are described.

[0040] Figure 1 The architecture of the tonometer provided by an embodiment of the present application is shown. As shown in Figure 1 The tonometer 100 in the embodiments of the present application includes a tonometer main body 110, which includes a probe 10, a drive coil 20 and a measurement coil 30. The drive coil 20 and the measurement coil 30 partially surround the probe. The drive coil 20 is used to drive the probe 10 to emit and generate displacement along the extension direction of the probe, and the measurement coil 30 is used to detect the motion state of the probe 10.

[0041] A power adjustment module 120 is electrically connected with the controller 130 and the drive coil 20, respectively.

[0042] The controller 130 is electrically connected with the measurement coil 30.

[0043] The controller 130 can be configured to perform the following steps: adjusting, by the power adjustment module 120, the first excitation voltage input to the drive coil 20 to cause the probe 10 to be launched in the probe extension direction under the drive of the drive coil 20 and to impact the cornea of the subject to be measured; obtaining a first correspondence between the first measurement voltage in the measurement coil 30 and the time during the rebounding of the probe 10 after impacting the cornea; determining, by the controller 130, the measured parameter value of the probe 10 at the instant of impacting the cornea using the first correspondence; in the case where the difference between the measured parameter value and the target parameter value is greater than a preset threshold, calculating a correction voltage using the difference; correcting the first excitation voltage to obtain a target excitation voltage according to the correction voltage; in the case where the difference between the measured parameter value and the target parameter value is less than or equal to the preset threshold, determining that the first excitation voltage is the target excitation voltage; and adjusting, by the power adjustment module 120, the voltage input to the drive coil 20 to the target excitation voltage, and completing multiple measurements of the intraocular pressure of the subject to be measured in the same measurement period at the target excitation voltage to obtain a final measurement result.

[0044] As understood by those skilled in the art, the first excitation voltage is an attempt excitation voltage for a trial hitting period by a user according to his / her man-machine distance and corneal sensitivity, and the first excitation voltage is a voltage within a safety interval according to the factory settings. The preset threshold is a value pre-stored in the system to ensure the safety of the rebound tonometer and to meet the regulatory requirements. The target parameter value can be a recommended speed value and / or energy value interval of the probe impacting the cornea of the subject to be measured corresponding to different man-machine distances and corneal sensitivities pre-set by the system. The size of the target parameter value can be pre-set by the technician according to the experience value, or the size of the target parameter value can also be set by the user according to his / her different needs. The measured parameter value refers to the actual measured speed value and / or energy value at the instant of impact. Further, the first excitation voltage can be a probe excitation voltage used by the user for trial hitting within the safety interval according to the specifications of the tonometer at the factory, and the ideal case is to calculate the target excitation voltage value according to the target parameter value of the probe impacting the cornea.

[0045] For example, the probe 10 can include a magnetic part and a plastic part, and the plastic part covers the end of the magnetic part so that the two are fixedly connected. In addition, the magnetic sleeve further includes a probe guide tube and a coil support, the probe 10 is installed in the probe guide tube which can be made of metal, and the coil support is sleeved outside the probe guide tube for mounting the drive coil 20 and the measurement coil 30. The distance between the proximal end of the magnetic part of the probe 10 and the proximal end of the drive coil 20 is L1.

[0046] For example, the controller 130 can change the voltage output to the drive coil 20 by controlling the power adjustment module 120, so as to change the excitation voltage applied to the probe 10 by the drive coil 20, and enable the probe 10 in the drive coil 20 to move at different initial energy or different initial speed towards the cornea of the subject. For example, after the probe 10 hits the cornea of the subject, the probe 10 can rebound along the extension direction of the probe 10. During the rebounding process, the probe 10 moves in the measurement coil 30, and the voltage in the measurement coil 30 changes. The controller 130 can determine the intraocular pressure of the subject by detecting the change of the voltage in the measurement coil 30. In an example, it can be understood that the parameter values of the probe, such as speed, acceleration, displacement and energy, also change after the probe hits the cornea of the subject. Therefore, the parameter values can be obtained in real time by the sensor, so as to determine the intraocular pressure of the subject. For example, the speed of the probe before and after hitting the cornea of the subject can be obtained by a speed sensor or an acceleration sensor, and the intraocular pressure of the subject can be calculated by using a related formula. In an example, the speed sensor can be the measurement coil 30.

[0047] In some optional embodiments, the probe 10 can be launched from a preset initial position. In this case, the initial position of the probe 10 can be a position where the distance between the first end 11 of the magnetic part of the probe 10 and the first end 21 of the drive coil 20 is the preset distance L1. It can be understood that the probe is launched at the same initial position, which is beneficial to improve the accuracy of the intraocular pressure measurement. In order to enable the probe 10 to be launched from the same initial position each time, the probe 10 needs to be pulled back to the initial position by the measurement coil 30 after each time hitting the cornea, i.e., the distance between the proximal end / first end 11 of the magnetic part of the probe 10 and the proximal end / first end 21 of the drive coil 20 is the preset distance L1. The specific method of pulling back the probe will be discussed below.

[0048] In the embodiments of the present application, the controller 130 changes the voltage input to the drive coil 20 by controlling the power adjustment module 120, so that the probe can hit the cornea of the subject at the target parameter value, thereby improving the accuracy of the intraocular pressure test.

[0049] Further, Figure 2 FIG. 6 shows a circuit architecture schematic diagram of a rebound tonometer provided by another embodiment of the present application. As shown in FIG. 6, the rebound tonometer provided by the embodiment of the present application comprises a power supply 110, a power adjustment module 120, a drive coil 20, a probe 10, a measurement coil 30, a controller 130 and a sensor 140. Figure 2As shown, the tonometer 100 in the embodiment of the present application further comprises: a voltage conversion device 140, comprising a power input end, a first input end, a first output end, and a feedback end, the controller 130 being connected with the first input end of the voltage conversion device 140; a first voltage regulating module 150, the first voltage regulating module 150 being connected between the first output end and the feedback end of the voltage conversion device 140; a filter module 160, one end of the filter module 160 being connected with the first output end of the voltage conversion device 140, and the other end of the filter module 160 being connected with the driving coil 20; wherein one end of the power regulating module 120 is connected with the controller 130, and the other end of the power regulating module 120 is connected with the first voltage regulating module 150; and a power supply 170, the power supply 170 being connected with the power input end of the voltage conversion device 140 and the controller 130 respectively, and supplying power to each element.

[0050] For example, the voltage conversion device 140 is used to realize the conversion between different voltage levels, and realize the function of voltage stabilization and efficiency improvement. In an example, the voltage conversion device 140 can be a DC-DC. It can be understood that the voltage conversion device can also be other devices with a feedback end and used to realize voltage conversion, and the specific structure of the voltage conversion device is not limited in the present application. In order to facilitate understanding, Figure 3 The circuit architecture schematic diagram of the rebound tonometer provided by another embodiment of the present application is shown, wherein, Figure 3 The specific connection mode of the voltage conversion device, the first voltage regulating module and the like is shown.

[0051] The first voltage regulating module 150 is connected between the first output end and the feedback end of the voltage conversion device 140, so as to be able to adjust the output voltage of the voltage conversion device 140, and by feeding back part of the voltage signal to the voltage conversion device 140, the voltage conversion device 140 can timely adjust its working state, and maintain the stability of the output voltage. The first voltage regulating module 150 can comprise a first resistor R1 and a second resistor R2. One end of the first resistor R1 is connected with the first output end of the voltage conversion device 140, and the other end of the first resistor R1 is connected with the feedback end of the voltage conversion device 140. One end of the second resistor R2 is connected with the feedback end, and the other end of the second resistor R2 is grounded. By feeding back the voltage between the first resistor R1 and the second resistor R2 to the voltage conversion device 140, the purpose of adjusting the output voltage of the voltage conversion device 140 is realized.

[0052] Further, in the presence of the power regulating module 120, since the power regulating module 120 is connected with the intermediate node of the first resistor R1 and the second resistor R2, the voltage of the intermediate node of the first resistor R1 and the second resistor R2 can be adjusted by the power regulating module 120, and the adjusted voltage is fed back to the voltage conversion device 140, so as to realize the purpose of adjusting the output voltage of the voltage conversion device 140 under the control of the controller 130.

[0053] The filter module 160 is configured to filter the voltage output by the voltage conversion device 140, so as to improve the stability of the voltage. In an example, the filter module 160 can be formed by a first capacitor CI, one end of the first capacitor CI is connected to the first output end of the voltage conversion device 140, and the other end of the first capacitor CI is grounded.

[0054] Thus, under the actions of the controller 130, the voltage conversion device 140, the first voltage regulating module 150, the filter module 160, and the power regulating module 120, the driving voltage VCC is output to the driving coil 20 or the measuring coil 30. Those skilled in the art can know that the driving voltage VCC is the voltage output by the adjusted circuit architecture.

[0055] Optionally, the circuit architecture of the tonometer 100 can further include a first switch device Q1 and a second switch device Q2. The first switch device Q1 is located between the filter module 160 and the driving coil 20, and the control end of the first switch device Q1 is connected to the controller 130. The controller 130 controls whether the driving voltage VCC can flow into the driving coil 20 by controlling the first switch device Q1. The second switch device Q2 is located between the filter module 160 and the measuring coil 30, and the control end of the second switch device Q2 is connected to the controller 130. The controller 130 controls whether the driving voltage VCC can flow into the measuring coil 30 by controlling the second switch device Q2. In an example, the first switch device Q1 and the second switch device Q2 can be transistors, including an on state and an off state, and the state of the transistor is controlled by the controller 130. Taking a P-channel metal-oxide-semiconductor field-effect transistor (PMOS) as an example, the gate of the PMOS is connected to the controller 130, the drain is connected to the driving voltage VCC, and the source is connected to the driving coil 20. When the controller 130 outputs a low level to the gate of the PMOS, the PMOS is turned on, and the voltage of the driving voltage VCC can flow to the driving coil 20; when the controller 130 outputs a high level to the gate of the PMOS, the PMOS is turned off, and the voltage of the driving voltage VCC cannot flow into the driving coil 20, and the driving coil 20 does not work.

[0056] Optionally, the circuit architecture of the tonometer 100 further includes a first voltage dividing resistor R0 and a second voltage regulating module resistor R0’. The first voltage dividing resistor R0 is connected between the output end of the first switch device Q1 and the driving coil 20; and the second voltage regulating module resistor R0’ is connected between the output end of the second switch device Q2 and the measuring coil 30. The voltage dividing resistors R0 and R0’ are used to protect the circuit.

[0057] The controller 130 controls the first switching device Q1 and the second switching device Q2 to control the power supply and power cutoff of the driving coil 20 and the measuring coil 30. Figure 3 The circuit architecture uses the same set of driving circuits to provide the required voltages to the driving coil 20 and the measuring coil 30. For example, when the probe needs to be pulled back, the measuring coil 30 is powered; when the probe needs to be launched, the driving coil 20 is powered. It will be understood by those skilled in the art that the various implementations of the power regulation module 120 described below can be used for Figure 3 circuit architecture.

[0058] In the present application, the power regulation module 120 performs power regulation in two ways: one is to change the voltage flowing into the control coil through a resistor, and the other is to directly change the voltage flowing into the drive coil 20 by adding a voltage input device.

[0059] For ease of understanding, the present application provides the following embodiments to illustrate the process of power regulation by the power regulation module 120 in two ways. In the embodiments provided in the present application, the voltage conversion device is a DCDC as an example. It is understandable that, due to the connection method and performance of the DCDC, when the voltage at the DCDC feedback terminal is changed, the actual output voltage of the DCDC will be changed. In addition, there is the following relationship between the actual output voltage and the voltage at the feedback terminal:

[0060]

[0061] Among them, Vout is the actual output voltage of DCDC; Vref is the voltage of DCDC feedback terminal, where the size of Vref is determined by the DCDC architecture itself; R1 and R2 are the impedances corresponding to the first resistor and the second resistor in the first voltage regulator module (the connection relationship between the first resistor and the second resistor can be referred to Figure 3 ).

[0062] In some optional embodiments, such as Figure 4 or Figure 5 As shown, the power regulation module 120 is a second voltage regulating module 121. The first end of the second voltage regulating module 121 is connected to the controller 130, the second end is connected to the first voltage regulating module 150, and the third end is grounded (GND). The second voltage regulating module is used to change the resistance of the resistor connected in the circuit, thereby changing the voltage input to the drive coil 20. Specifically, the second voltage regulating module 121 is connected to the second resistor R2. By changing the total resistance of R2 and the second voltage regulating module 121, the voltage fed back to the voltage conversion device 140 at the node between the first resistor R1 and the second resistor R2 is adjusted.

[0063] Specifically, in one example, Figure 4As shown in FIG. 1, the power regulating module 120 is a second voltage regulating module 121. The second voltage regulating module 121 can be composed of a plurality of resistors connected in series. The plurality of resistors can include R3, R4,..., Rn, and each resistor can have the same or different resistance. Each resistor can be configured with a corresponding switch K0 to control whether the resistor is connected in the circuit. The on or off of each switch K0 can be controlled by the controller 130. Alternatively, the switch K0 can be controlled by the user of the rebound tonometer (not shown in FIG. 1). For example, the switch K0 can be a control button, and the user of the rebound tonometer can press different control buttons to change the size of the resistor connected in the circuit, thereby adjusting the input voltage of the drive coil. Figure 4 As shown in FIG. 2, the power regulating module 120 is a second voltage regulating module 121. The second voltage regulating module 121 can be composed of a plurality of resistors connected in series. The plurality of resistors can include R3, R4,..., Rn, and each resistor can have the same or different resistance. Each resistor can be configured with a corresponding switch K0 to control whether the resistor is connected in the circuit. The on or off of each switch K0 can be controlled by the controller 130. Alternatively, the switch K0 can be controlled by the user of the rebound tonometer (not shown in FIG. 1). For example, the switch K0 can be a control button, and the user of the rebound tonometer can press different control buttons to change the size of the resistor connected in the circuit, thereby adjusting the input voltage of the drive coil.

[0064] As shown in FIG. 3, the power regulating module 120 is a second voltage regulating module 121. The second voltage regulating module 121 can be composed of a plurality of resistors connected in series. The plurality of resistors can include R3, R4,..., Rn, and each resistor can have the same or different resistance. Each resistor can be configured with a corresponding switch K0 to control whether the resistor is connected in the circuit. The on or off of each switch K0 can be controlled by the controller 130. Alternatively, the switch K0 can be controlled by the user of the rebound tonometer (not shown in FIG. 1). For example, the switch K0 can be a control button, and the user of the rebound tonometer can press different control buttons to change the size of the resistor connected in the circuit, thereby adjusting the input voltage of the drive coil. Figure 5

[0065] It can be understood that in the above embodiments of changing the resistance, by changing the voltage division of the DCDC feedback voltage by the resistance, the overall impedance of the second resistor R2 and the second voltage regulating module 121 (i.e., the overall resistance) is changed, thereby adjusting the voltage Vout actually output by the DCDC.

[0066] In some alternative embodiments, the voltage input device changes the voltage input to the drive coil 20, as shown in FIG. 4 or FIG. 5. Figure 6 Figure 7 Figure 6 is another embodiment of the circuit structure, as shown in FIG. 6, the power regulating module 120 is a second excitation voltage input module 122. One end of the second excitation voltage input module 122 is connected to the controller 130, and the other end is connected to the first voltage regulating module 150. By changing the voltage connected in the circuit through the second excitation voltage input module 122, the voltage input to the drive coil 20 is changed. Figure 6

[0067] Specifically, as shown in FIG. 7, the power regulating module 120 is a second excitation voltage input module 122. One end of the second excitation voltage input module 122 is connected to the controller 130, and the other end is connected to the first voltage regulating module 150. By changing the voltage connected in the circuit through the second excitation voltage input module 122, the voltage input to the drive coil 20 is changed. Figure 6 ​​​​As shown, the power regulating module 120 can be a second excitation voltage input module 122, which outputs a voltage signal to the first voltage regulating module 150. The voltage signal can be a PWM signal. The power regulating module 120 further includes a low pass filter 124 after the output PWM signal, which filters the output PWM signal. The low pass filter 124 is composed of a fourth resistor R4 and a second capacitor C2. The first end of the fourth resistor R4 receives the PWM signal output by the MCU, and the second end of the fourth resistor R4 is connected to the first voltage regulating module 150. One end of the second capacitor C2 is connected to the second end of the fourth resistor R4, and the other end of the second capacitor C2 is grounded. It can be understood that, for the protection of the circuit, the power regulating module 120 further includes a third resistor R3, which is connected in series between the low pass filter 124 and the first voltage regulating module 150 to avoid short circuit of the circuit.

[0068] In another example, Figure 7 The circuit schematic diagram of the second excitation voltage input module 122 provided by another embodiment of the present application is shown in FIG. 4. As shown in FIG. 4, Figure 7 As shown, the second excitation voltage input module 122 can include a digital to analog converter (DAC) for converting a digital signal into an analog voltage or current output. The first end of the second excitation voltage input module 122 can be connected to the controller 130, the second end is connected to the first voltage regulating module 150, the third end is grounded, and the power supply 170 supplies power thereto. Similarly, the second excitation voltage input module 122 further includes a third resistor R3 connected in series between the DAC and the first voltage regulating module 150 to avoid short circuit of the circuit.

[0069] In yet another example, the voltage conversion device 140 is a programmable voltage regulator, such as a linear voltage regulator and / or a switching voltage regulator. In this example, the programmable switching voltage regulator adjusts the output voltage through a digital interface to meet different voltage requirements.

[0070] In yet another example, Figure 3 For example, the controller 130 can adjust the switching frequency of the first switching device Q1 to change the voltage input to the drive coil 20. It can be understood that the controller 130 can adjust the switching frequency of the first switching device by changing the duty cycle of the high and low levels in the drive signal input to the first switching device Q1, thereby changing the voltage input to the drive coil 20.

[0071] It can be understood that in the above examples of changing the voltage, by inputting a voltage to the DCDC feedback end or directly changing the voltage input to the DCDC, the voltage value of the DCDC feedback end Vref in formula (1) is changed, thereby adjusting the voltage Vout actually output by the DCDC.

[0072] It can be understood that the above embodiments are only exemplary descriptions of the DCDC voltage conversion device, and other corresponding relationships between the feedback end and the actual output voltage can exist for other voltage feedback devices. Therefore, the power regulation module, the connection relationship, and the regulation method described in the above embodiments are only exemplary descriptions, and the voltage in the regulation circuit can also be regulated by other devices or electronic components, which are not limited in the embodiments of the present application.

[0073] In the embodiments of the present application, the power regulation module 120 can be used to change the voltage of the input drive coil 20.

[0074] The rebound tonometer provided in the embodiments of the present application is introduced below.

[0075] Figure 8 A flowchart of the eye pressure test method provided by an embodiment of the present application is shown. As shown in Figure 8 The eye pressure test method in the embodiments of the present application includes the following steps:

[0076] S810, the first excitation voltage of the input drive coil 20 is regulated by the power regulation module 120, so that the probe 10 is emitted in the probe extension direction under the drive of the first excitation voltage.

[0077] The first excitation voltage is the attempt excitation voltage of the user within the safety interval set by the factory during the trial period, and the ideal case is the target excitation voltage calculated by the technician according to the target parameter value.

[0078] The drive coil 20 charges the probe under the drive of the first excitation voltage, so that the probe can hit the cornea of the object to be measured.

[0079] For example, the power regulation module 120 can change the first excitation voltage output by the voltage conversion device 140, and the drive coil 20 can generate a certain driving force under the excitation of the first excitation voltage, so that the probe in the drive coil is emitted in the probe extension direction.

[0080] The size of the target parameter value can be set by the technician according to experience or by the user according to different needs. In an example, the technician sets the target parameter value as the speed value or the corresponding energy value at the moment of impact on the cornea according to experience at the factory, and the intraocular pressure calculated and measured at the speed value is more objective within the allowable range. That is, at the target driving voltage, the probe is driven to emit, and at the recommended distance between the tonometer and the cornea, the speed value / energy value at the moment of impact is the target parameter value. In another example, if the user is sensitive to the touch when the probe impacts the eyeball, the size of the target parameter value can be set to a lower threshold, thereby reducing the discomfort of the user when the probe impacts the eyeball. It can be understood that the lower threshold set can be a smaller value in a parameter interval that meets the measurement requirements of the intraocular pressure. It should be noted that the target parameter value is adjusted between the maximum value and the minimum value preset by the system under the premise of meeting the functional implementation and safety requirements of the tonometer.

[0081] S820, after the probe 10 impacts the cornea, the first correspondence between the first measurement voltage in the measurement coil 30 and the time is obtained by the controller 130 during the rebound of the probe 10 in the opposite direction.

[0082] In an example, the probe 10 rebounds after impacting the cornea of the measured object, and the probe generates displacement in the measurement coil 30, thereby generating the first measurement voltage. The controller 130 is connected to the measurement coil 30 and can obtain the first correspondence between the first measurement voltage generated in the measurement coil 30 and the time, that is, the function of the first measurement voltage and the time.

[0083] S830, the controller 130 determines the measured parameter value of the probe 10 at the moment of impact on the cornea by using the first correspondence.

[0084] In an example, the controller 130 can calculate the measured parameter value of the probe 10 when impacting the cornea of the measured object according to the first correspondence. The measured parameter value is used to represent the actual parameter value generated when the probe impacts the cornea of the measured object. The parameter value is, for example, the instantaneous speed value, the acceleration value, the energy value, etc., which is related to the energy at the moment of impact.

[0085] In an example, the first correspondence can be the correspondence between the first measurement voltage and the time. The first correspondence can be obtained by the controller 130.

[0086] S840, in the case that the difference between the measured parameter value and the target parameter value is greater than a preset threshold, the correction voltage is calculated by using the difference.

[0087] For example, the controller 130 can calculate the difference between the measured parameter value and the target parameter value, and calculate the correction voltage using the difference when the difference is greater than the preset threshold.

[0088] In an example, the difference between the first measured value and the target parameter value can represent the difference between the parameter value carried by the probe when actually hitting the cornea and the parameter value required by the technician or user.

[0089] S850, correct the first excitation voltage according to the correction voltage to obtain a target excitation voltage.

[0090] For example, the controller 130 can correct the first excitation voltage by the calculated correction voltage to obtain the target excitation voltage.

[0091] S860, in the case where the difference between the measured parameter value and the target parameter value is less than or equal to the preset threshold, determining the first excitation voltage as the target excitation voltage.

[0092] For example, the controller 130 can determine the first excitation voltage as the target excitation voltage when the difference between the measured parameter value and the target parameter value is less than or equal to the preset threshold.

[0093] S870, measuring the intraocular pressure of the object to be measured according to the target excitation voltage to obtain the final measurement result of the same measurement period.

[0094] For example, the controller can control the power adjustment module 120 to adjust the voltage, output the target excitation voltage to the driving coil 20 through the power adjustment module 120, and test the intraocular pressure of the object to be measured based on the target excitation voltage. It should be noted that in step S860, the distance between the cornea of the user and the tonometer is determined, and the target excitation voltage is determined, and on this basis, the user starts a measurement period, that is, multiple repeated measurements are performed. In this measurement period, the intraocular pressure values of each measurement are basically the same, and the output intraocular pressure value of the measurement period given after calculation can truly reflect the intraocular pressure condition.

[0095] In the embodiment of the application, the controller 130 can control the power adjustment module 120 to output the first excitation voltage to the driving coil 20 in the tonometer main body, so that the probe in the tonometer main body hits the cornea of the object to be measured under the driving of the first excitation voltage. After the probe hits the cornea of the object to be measured, the probe will rebound, and at this time, the controller 130 can determine the measured parameter value of the probe 10 when hitting the cornea through the first correspondence between the first measurement voltage generated in the measurement coil 30 in the tonometer main body and the time. By calculating the difference between the actual measured parameter value generated by the probe 10 when hitting the cornea of the object to be measured and the target parameter value, it can be determined whether the size of the first excitation voltage needs to be adjusted.

[0096] In the case where it is determined that the difference is greater than the preset threshold, it can be determined that the user will have an uncomfortable experience or the accuracy of the tonometry measurement will be adversely affected when the probe 10 is driven at the first excitation voltage. Therefore, the voltage value that needs to be adjusted for the first excitation voltage can be determined by the difference, i.e., the corrected voltage is calculated. Further, the first excitation voltage can be corrected by the corrected voltage to obtain the target excitation voltage. In the case of measuring the intraocular pressure according to the target excitation voltage, it is ensured that the probe can hit the cornea of the object to be measured at the target parameter value, thereby ensuring the consistency of the measured intraocular pressure result and improving the accuracy of the tonometry measurement. Further, it can be understood that measuring the object to be measured according to the target parameter value can be used to have a better user experience when measuring the intraocular pressure and reduce the discomfort of the user during the intraocular pressure measurement.

[0097] If the difference is less than or equal to the preset threshold, the first excitation voltage is considered as the target excitation voltage, and the measurement is considered as the first measurement in a measurement period.

[0098] In some optional embodiments, step S860 can include the following steps:

[0099] S861, adjusting the voltage input to the drive coil to the target excitation voltage by the power adjustment module.

[0100] For example, the controller 130 can adjust the voltage input to the drive coil 20 to the target excitation voltage by the power adjustment module.

[0101] In a special case, in the case where the first excitation voltage is determined as the target excitation voltage, the intraocular pressure of the object to be measured is calculated using the measured parameter value to obtain a single intraocular pressure measurement result, and the measurement result is recorded as the 1st measurement result in the same measurement period.

[0102] It can be understood that in order to improve the user experience of the rebound tonometer, the measured parameter value of the probe hitting the cornea of the user under the first excitation voltage can meet the target parameter value, at which time the measurement process can be considered as the 1st measurement in the same measurement period. The intraocular pressure of the object to be measured is calculated by the measured parameter value to obtain a single intraocular pressure measurement result.

[0103] S862, exciting the drive coil according to the target excitation voltage to make the probe emit along the probe extension direction.

[0104] For example, under the target excitation voltage, the probe can be emitted along the probe extension direction and hit the cornea of the object to be measured.

[0105] S863, obtaining the target correspondence between the second measurement voltage in the measurement coil and the time by the controller during the process of the probe rebounding in the opposite direction after hitting the cornea.

[0106] The second measurement voltage can be a voltage generated in the measurement coil 30 when the probe moves after the probe hits the cornea at the target parameter value. For example, after the probe hits the cornea of the subject at the target parameter value, the probe rebounds and generates the second measurement voltage in the measurement coil.

[0107] The controller 130 can obtain a correspondence between the second measurement voltage and the time as the target correspondence.

[0108] S864, according to the target correspondence, the energy value of the probe at the moment of hitting the cornea is calculated.

[0109] For example, the controller 130 can obtain the target correspondence between the second measurement voltage and the time in the measurement coil 30, and calculate the energy value of the probe at the moment of hitting the cornea according to the obtained target correspondence. In one example, the energy value of the probe at the moment of hitting the cornea can be calculated by a correlation formula, such as a magnetic energy formula.

[0110] S865, the intraocular pressure of the subject is calculated by using the energy value at the moment of hitting to obtain a single measurement result.

[0111] It should be noted that the measurement result is only recorded and stored, and is not used as the final intraocular pressure value measurement result.

[0112] For example, the controller 130 can determine the intraocular pressure value of the subject by the calculated energy value. The determined intraocular pressure value is used as the single measurement result. In one example, the energy difference of the probe before and after hitting the cornea of the subject can be calculated to determine the intraocular pressure of the subject according to the difference.

[0113] S866, it is judged whether N measurements in the same measurement period are completed; if yes, S867 is executed, and if no, S862 is returned.

[0114] S868, the target measurement result is calculated according to the N single measurement results in the same measurement period.

[0115] For example, the controller 130 can judge whether the measurement result is the Nth measurement result. If the controller 130 judges that the measurement result is the Nth measurement result, the target measurement result can be calculated by using the obtained N measurement results. The target measurement result can be the actual measurement result obtained by the user. In one example, the average of the N single measurement results can be calculated, and the average is used as the actual measurement result. In another example, the weighted average of the N single measurement results can be calculated, and the weighted average is used as the actual measurement result.

[0116] It can be understood that the N measurement results used to calculate the intraocular pressure of the to-be-measured object are N measurement results generated under the target excitation voltage. In an example, if the difference between the measured parameter value and the target parameter value is greater than the preset threshold, the target excitation voltage can be calculated first, and after the target excitation voltage is calculated, the N measurement results under the target excitation voltage are obtained. In another example, if the difference between the measured parameter value and the target parameter value is less than or equal to the preset threshold, the first excitation voltage can be used as the target driving voltage, and the current measurement result can be used as the first of the N measurement results. Further, under the driving of the first excitation voltage, N-1 measurement results are further obtained to determine the output intraocular pressure of the current measurement period.

[0117] In one measurement period, N measurements are performed, and N can be a positive integer. N can be determined by a technician according to experience. For example, N can be 6, that is, the actual intraocular pressure measurement result can be determined according to 6 measurement results.

[0118] In the embodiments of the present application, N measurements of the intraocular pressure of the to-be-measured object are performed according to the target excitation voltage, and the actual intraocular pressure measurement result is determined according to the N measurement results. In this way, the finally determined intraocular pressure measurement result has better accuracy.

[0119] For example, the parameter value can be used to measure the physical characteristics possessed / carried by the probe at the moment of impacting the cornea of the to-be-measured object. The measured parameter value can be the physical characteristics possessed / carried by the probe at the moment of impacting the cornea when the probe is driven according to the first excitation voltage. The target parameter value can be an ideal value of the physical characteristics possessed / carried by the probe when impacting the cornea, which is set by a technician in advance.

[0120] For example, the parameter can be an energy parameter or a speed parameter. Therefore, when the parameter value is different physical quantities, the determination method is also different. The following examples are combined to introduce the determination process of the first energy value and the first speed value when the parameter is an energy parameter and the parameter is a speed parameter, respectively.

[0121] In some optional embodiments, when the measured parameter is an energy parameter, step S830 in the embodiments of the present application can include the following steps:

[0122] S831, integrating the first measurement voltage corresponding to the first time to the second time by the first corresponding relationship to determine the first displacement of the probe.

[0123] wherein the first measurement voltage is a voltage generated in the measurement coil 30 after the probe 10 impinges the cornea under the drive of the first excitation voltage. Wherein the drive coil charges the probe under the excitation of the first excitation voltage, so that the probe 10 is launched at the first time, the probe 10 travels a preset distance and impinges the cornea at the second time with a target parameter value. It can be understood that the preset distance can be a distance value between the probe and the cornea of the object to be measured predetermined by the tonometer in the manufacturing process.

[0124] wherein the first displacement represents a distance moved by the probe from the first time to the second time. The first time is a time corresponding to the moment of launching the probe, and the second time is a time corresponding to the moment of impinging the cornea. It can be understood that the first displacement is a displacement of the probe from the initial launching position to the position corresponding to impinging the cornea.

[0125] Exemplarily, after the first measurement voltage is obtained, the first displacement can be obtained by integrating the first measurement voltage from the first time to the second time. In an example, the first correspondence between the first measurement voltage and the time can be represented by the following formula:

[0126]

[0127] Φ = k1 * x (3)

[0128]

[0129] wherein formula (2) is Faraday's law of electromagnetic induction, and formula (3) is a correspondence between the magnetic flux and the displacement of the probe, wherein k1 depends on the specific configuration of the magnetic field and the geometric shape of the measurement coil. Formula (3) is brought into formula (2) to obtain formula (1), obtaining the first correspondence between the first measurement voltage and the time. Wherein E can be an electromotive force in the circuit, i.e. the first measurement voltage in the measurement coil; Φ can be the magnetic flux passing through the measurement coil; may be the rate of change of the magnetic flux with respect to time. Further, it can be seen from the expression of formula (4) that the displacement χ of the probe can be calculated by integrating the time t, i.e. the lower limit of integration is the first time and the upper limit of integration is the second time.

[0130] S832, determining a second correspondence between the energy W and the displacement χ through the first correspondence between the first measurement voltage and the time.

[0131] Exemplarily, the controller 130 can obtain the second correspondence between the energy and the displacement through the first correspondence and corresponding calculation on the first correspondence.

[0132] In some optional embodiments, the fourth correspondence between the driving force and the displacement can be determined by the first correspondence between the first measured voltage and the time and the force relationship of the probe. Further, the second correspondence between the energy and the displacement can be determined by the fourth correspondence between the driving force and the displacement.

[0133] For example, the force analysis of the probe can be performed to determine the magnitude of the resultant force of the probe at different positions of the driving coil, and the correspondence between the resultant force of the probe and the displacement is obtained. Further, the correspondence between the driving force of the probe and the displacement is determined. It can be understood that the driving force of the probe is provided by the driving coil. In an example, Figure 9 FIG. 8 shows a schematic diagram of the fourth correspondence between the driving force of the probe and the displacement according to an embodiment of the present application. Figure 9 As shown in FIG. 8, in the fourth correspondence, the horizontal axis represents the displacement x of the probe, and the vertical axis represents the driving force F. The origin is the initial position of the probe; the probe performs uniform acceleration motion in the interval from the origin to L1, the probe performs variable deceleration motion in the interval from L1 to L1+L2, and the probe performs uniform deceleration motion in the interval from L1+L2 to L1+L2+L3. It should be noted that the above description should be combined with Figure 1 and Figure 9 , the probe performs uniform acceleration motion in the interval L1, which is equivalent to the distance between the first end 11 of the magnetic part of the probe and the first end 21 of the driving coil, i.e., the probe performs uniform acceleration motion in the interval L1 after being launched from the initial position. After passing the proximal end of the driving coil 20, the probe receives the reverse force from the driving coil 20.

[0134] For example, the second correspondence between the energy and the displacement can be determined by integrating the fourth correspondence between the driving force and the displacement. In an example, the controller 130 can obtain the function expression of the driving force and the displacement, i.e., F-x, according to the first excitation voltage and the force expression of the probe, which is reflected as a function of Figure 9 The first displacement determined by the first correspondence is substituted into the F-x curve, and the F-x curve is integrated to obtain the energy value W of the probe at the impact moment. During the integration, the acceleration and the driving force are positive and negative, so the energy value W of the probe is the area above the x axis minus the area below the x axis. The correspondence between the energy value W of the probe and the displacement x is shown in FIG. 9. Figure 10 Figure 10 FIG. 10 shows a schematic diagram of the second correspondence according to an embodiment of the present application. Wherein Wexpection is the target energy value corresponding to the energy parameter as the target parameter, i.e., the expected energy value at the impact moment.

[0135] S833, according to the second correspondence, the energy value corresponding to the first distance is determined as the measured energy value of the probe when impacting the cornea.​

[0136] For example, the controller can be configured to generate a second corresponding relationship between energy and displacement (e.g. Figure 10 ), determine that the energy value corresponding to the first distance is the actual energy value of the probe at the moment of impacting the cornea. Figure 10 As shown in FIG, the energy value corresponding to the displacement L1+L2+L3 is the measured energy value. Here, the probe hits the cornea, that is, the probe moves to the distance d0 between the initial position of the probe proximal end and the cornea.

[0137] In the embodiment of the present application, the controller can determine the first displacement of the probe movement by obtaining the first corresponding relationship between voltage and time, and determine the second corresponding relationship between energy and displacement according to the first corresponding relationship (such as Figure 10 ), thereby determining the measured energy value corresponding to the first displacement in the second correspondence. Therefore, in this embodiment of the present application, the controller only needs to obtain the voltage value and time in the measuring coil to determine the energy value when the probe strikes the cornea. This allows for obtaining energy values ​​with less equipment, reducing the cost of the tonometer.

[0138] In some optional embodiments, when the measured parameter is a speed parameter, step S830 may include the following steps:

[0139] S834. Integrate the first measurement voltage corresponding to the time period between the first time and the second time according to the first corresponding relationship to determine the first displacement of the probe.

[0140] The first displacement represents the distance the probe moves from the first time to the second time.

[0141] S835. Determine a second corresponding relationship between energy and displacement based on a first corresponding relationship between the first measured voltage and time.

[0142] S836, through the second corresponding relationship between energy and displacement (such as Figure 10 As shown) and the kinetic energy theorem, the third corresponding relationship between velocity and displacement is determined (as shown Figure 11 shown).

[0143] S837. Determine, based on the third corresponding relationship, that the velocity value corresponding to the first distance is the actual velocity value of the probe when it impacts the cornea.

[0144] Among them, steps S834-S837 are consistent with steps S831-S833 and will not be described in detail here.

[0145] For example, the controller can use the second corresponding relationship between energy and displacement (such as Figure 10 As shown in the figure) and the kinetic energy theorem, the third correspondence between velocity and displacement is determined. The correspondence between the probe velocity and displacement is as followsFigure 11 As shown, Figure 11 A schematic diagram of a third corresponding relationship provided by an embodiment of the present application is shown, wherein Vexpection is the target velocity value corresponding to the target parameter being the velocity parameter, i.e., the impact velocity expected when the probe strikes the cornea.

[0146] For example, the controller may determine, based on the third correspondence between speed and displacement, that the speed value corresponding to the first distance is the actual speed value of the probe when it hits the cornea. Figure 10 As shown, the speed value corresponding to the displacement L1+L2+L3 is the first speed parameter.

[0147] In the embodiment of the present application, the controller can determine the first displacement of the probe movement by obtaining the first corresponding relationship between voltage and time, and determine the second corresponding relationship between energy and displacement based on the first corresponding relationship ( Figure 10 ), further, the third corresponding relationship is determined using the second corresponding relationship ( Figure 11 ), thereby determining the measured velocity value corresponding to the first displacement in the third correspondence. Therefore, in this embodiment of the present application, the controller only needs to obtain the voltage value and time in the measuring coil to determine the velocity of the probe when it impacts the cornea. This allows for obtaining velocity values ​​with less equipment, reducing the cost of the tonometer.

[0148] Furthermore, when the measured parameters are different, the process of determining the correction voltage is also different. Therefore, the following examples respectively describe the process of determining the correction voltage when the measured parameters are energy parameters and speed parameters.

[0149] In some optional embodiments, when the measured parameter is an energy parameter, step S840 may include the following steps:

[0150] S841. Calculate the energy difference between the measured energy value and the target energy value.

[0151] For example, the energy difference between the measured energy value and the target energy value may represent the energy difference between the energy of the probe when it actually strikes the cornea and the energy set by the technician.

[0152] S842: Calculate the distance difference between the first displacement and the preset distance.

[0153] For example, the distance difference between the first displacement and the preset distance may represent the distance difference between the actual displacement of the probe and the probe displacement preset by the technician.

[0154] S843. Calculate the corrected driving force based on the distance difference and the energy difference.

[0155] It can be understood that the distance difference is actually the distance difference generated by the probe in the process of uniform deceleration, and thus the driving force of the probe in the process of uniform deceleration is determined according to the formula of force and displacement. In an example, in combination with Figure 9 The distance difference is actually the distance difference generated by the probe in the process of uniform deceleration. Please combine Figure 1 It can be understood that the probe 10 is in an initial position, and the distance between the proximal end of the probe metal part (including the part wrapped by the plastic part) and the proximal end of the driving coil is L1. After the probe is ejected, due to L1 or even the entire first displacement, which is small compared to the overall size of the probe, it can be considered that the frictional force acting on the probe during the entire movement process is a constant value. According to the force analysis formula (5) of the probe:

[0156] F 合力 =F 驱动 -f 阻力 (5)

[0157] In the process of moving L1 from the initial position, the probe 10 is driven by the driving coil 20, and the driving force is calculated to be approximately constant. Therefore, the resultant force does not change, and the probe experiences a uniform acceleration charging process until the metal of the probe metal part and the proximal end of the driving coil are flush, and the displacement of the probe is L1. For example, L1 can be 2 mm. During the uniform acceleration process, the initial energy imparted to the probe is only related to the acceleration and driving force brought by the driving voltage or driving power of the driving coil. Among them, Figure 9 Fmax in the formula is a preset maximum value; Fmin is a preset minimum value; Fdefault is the driving force corresponding to the first driving voltage, which can be set according to the empirical value, can be adjusted by the user according to the user's sense of touch, or can be understood as the driving force corresponding to the first driving voltage of the probe. It can be understood that the length of L1 is only related to the structure of the tonometer itself.

[0158] When the displacement of the probe exceeds L1, that is, the movement of the probe is between L1 and L1+L2, the metal part of the probe exceeds the proximal end of the driving coil, and thus the acceleration rapidly decreases, and the probe begins to decelerate. This stage is not related to the impact, but only related to the structure of the tonometer itself (such as the length of the driving coil, the frictional force, and the smoothness), and is approximately considered to be unchanged.

[0159] When the displacement of the probe exceeds L1+L2, the probe begins to move at a uniform deceleration under the action of a constant resistance until it hits the cornea of the object to be measured. Therefore, it can be understood that since L1 and L2 are constant values, the distance difference is actually the distance difference generated by the probe in the process of uniform deceleration, that is, L3.

[0160] S844, determine the correction voltage corresponding to the correction driving force by using the magnetic energy formula.

[0161] For example, the expression of the magnetic energy formula can be represented by the following formula (6):

[0162]

[0163] wherein F represents the driving force received by the probe, R m represents the magnetic resistance; χ represents the displacement of the probe; N represents the number of turns of the coil; g represents the air gap; μ0 represents the air permeability, wherein μ0 can be 1; d m represents the diameter of the probe; l s represents the length of the probe; V represents the voltage; and k represents a constant coefficient.

[0164] For example, the corrected voltage can be calculated by the above formula (6).

[0165] In the embodiments of the present application, the calculation of the corrected voltage can be realized by determining the energy difference between the measured energy value and the target energy value.

[0166] Further, in some optional embodiments, when the measured parameter is a speed parameter, S840 in the embodiments of the present application can include the following steps:

[0167] S845, calculating the speed difference between the measured speed value and the target speed value.

[0168] S846, calculating the corrected energy by the speed difference.

[0169] S847, calculating the distance difference between the first displacement and the preset distance.

[0170] S848, calculating the corrected driving force by the distance difference and the corrected energy.

[0171] S849, determining the corrected voltage corresponding to the corrected driving force by the magnetic energy formula.

[0172] For example, the speed difference between the first speed parameter and the target speed parameter can be calculated, and then the corrected energy can be calculated according to the kinetic energy theorem. After the corrected energy is determined, the corrected driving force can be calculated according to the corrected energy and the first displacement, and further, the corrected voltage corresponding to the corrected driving force can be determined by the magnetic energy formula. The calculation process of the corrected driving force and the calculation process of the corrected voltage are not described herein.

[0173] In the embodiments of the present application, the calculation of the corrected voltage can be realized by determining the speed difference between the first speed parameter and the target speed parameter.

[0174] To improve the accuracy of intraocular pressure measurement, the probe can be launched at the same initial position. Therefore, before launching the probe according to the first excitation voltage, the controller 130 controls the measuring coil 30 to retract the probe 10 to the initial position. As another implementation of the present application, the present application also provides another implementation of intraocular pressure measurement, which is described in detail in the following embodiments.

[0175] In some optional embodiments, before the power regulation module outputs the first excitation voltage to the drive coil to cause the probe to launch along the probe extension direction, the intraocular pressure testing method in the embodiment of the present application further includes the following steps:

[0176] S870: Output a second excitation voltage to the measuring coil through the controller, so that the probe is pulled back to the initial position along the extending direction of the probe.

[0177] For example, the controller may output a second excitation voltage to the measuring coil to pull the probe back to its initial position along its extension direction. The second excitation voltage may be a relatively high excitation voltage, and the tonometer may include a fixing structure to secure the probe in its initial position after being pulled back.

[0178] For example, Figure 3 For example, the controller 130 can control the measuring coil 30 by controlling the second switching device Q2. In one example, the second switching device Q2 is a PMOS transistor, with its gate connected to the controller 130, its drain connected to the drive voltage VCC, and its source connected to the drive coil 20. When the controller 130 outputs a low level to the gate of the second switching device Q2, the PMOS transistor turns on, allowing the drive voltage VCC to flow to the measuring coil 30, enabling the measuring coil 30 to perform its pull-back function. When the controller 130 outputs a high level to the gate of the second switching device Q2, the PMOS transistor turns off, preventing the drive voltage VCC from flowing to the measuring coil 30, and the measuring coil 30 stops functioning.

[0179] In an embodiment of the present application, the probe is pulled back to its initial position before being launched according to the first excitation voltage, thereby ensuring that the probe can accelerate over the same distance, thereby ensuring that the probe can obtain the same initial parameter values, including speed parameters and energy parameters, thereby improving the accuracy of intraocular pressure measurement.

[0180] The aspects of the disclosure described above with reference to the flowcharts and / or block diagrams of the tonometer, the tonometry method according to embodiments of the present disclosure. It should be understood that each block of the flowchart and / or block diagram and combinations of blocks in the flowchart and / or block diagram can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, enable the implementation of the functions / acts specified in the flowchart and / or block diagram block or blocks. Such a processor can be, but not limited to, a general- purpose processor, a special-purpose processor, a special-purpose application specific processor, or a field programmable logic array. It should also be understood that each block of the flowchart and / or block diagram and combinations of blocks in the flowchart and / or block diagram can also be implemented by dedicated hardware, or a combination of dedicated hardware and computer instructions. It should be understood that the embodiments of the present disclosure can be implemented by one or more computer programs or software, which execute on one or more computers or other programmable apparatuses to produce the functions / acts specified in the flowchart and / or block diagram block or blocks, and each block of the flowchart and / or block diagram and combinations of blocks in the flowchart and / or block diagram can be implemented by computer program instructions.

[0181] The above description is merely a specific implementation of the present application. Those skilled in the art can clearly understand the specific working process of the system, module and unit described above for the convenience and brevity of description, which can refer to the corresponding process in the foregoing method embodiments, which will not be described here. It should be understood that the protection scope of the present application is not limited to this. Any person skilled in the art can easily think of various equivalent modifications or replacements within the technical range disclosed in the present application, and these modifications or replacements should be covered within the protection scope of the present application.

Claims

1. A rebound tonometer, characterized in that: include: a tonometer body, the tonometer body comprising a probe, a drive coil, and a measuring coil, wherein the drive coil and the measuring coil partially surround the probe, the drive coil is used to drive the probe to emit and generate displacement along the probe extension direction, and the measuring coil is used to detect the motion state of the probe; a power regulation module, the power regulation module being electrically connected to the controller and the drive coil respectively; The controller is electrically connected to the measuring coil and is used to perform the following operations: regulating a first excitation voltage input to the driving coil through a power regulating module, so that the probe is driven by the first excitation voltage to emit along the extending direction of the probe; During the process of the probe rebounding in the opposite direction after striking the cornea, obtaining a first corresponding relationship between a first measurement voltage in the measuring coil and time; Determining, by the controller, the measured parameter value of the probe at the moment of impacting the cornea using the first corresponding relationship; When the difference between the measured parameter value and the target parameter value is greater than a preset threshold, calculating a correction voltage using the difference; Correcting the first excitation voltage according to the correction voltage to obtain a target excitation voltage; When the difference between the measured parameter value and the target parameter value is less than or equal to a preset threshold, determining the first excitation voltage as a target excitation voltage; The intraocular pressure of the subject to be measured is measured according to the target excitation voltage to obtain a final measurement result of the same measurement cycle.

2. The rebound tonometer according to claim 1, wherein Also includes: A voltage conversion device, comprising a power input terminal, a first input terminal, a first output terminal and a feedback terminal; a first voltage regulating module, wherein the first voltage regulating module is connected between the first output terminal and the feedback terminal; a filtering module, one end of the filtering module being connected to the first output end, and the other end of the filtering module being connected to the driving coil; Wherein, the first end of the power regulating module is connected to the controller, and the second end of the power regulating module is connected to the first voltage regulating module; A power supply is connected to the power input terminal of the voltage conversion device and the controller respectively.

3. The rebound tonometer according to claim 2, wherein: It also includes a first switch device and a second switch device, wherein the first switch device is located between the filter module and the drive coil and is connected to the controller; the second switch device is located between the filter module and the measuring coil and is connected to the controller.

4. The rebound tonometer according to claim 3, characterized in that It also includes a first voltage-dividing resistor and a second voltage-dividing resistor, wherein the first voltage-dividing resistor is connected between the first switching device and the driving coil, and the second voltage-dividing resistor is connected between the second switching device and the measuring coil.

5. The rebound tonometer according to any one of claims 1 to 4, characterized in that The power regulation module includes: a second voltage regulating module, wherein a first end of the second voltage regulating module is connected to the controller, and a second end of the second voltage regulating module is connected to the first voltage regulating module; or A second excitation voltage input module, wherein a first end of the second excitation voltage input module is connected to the controller, and a second end of the second excitation voltage input module is connected to the first voltage regulating module.

6. The rebound tonometer according to claim 5, characterized in that The second voltage regulating module includes at least one of the following: a variable resistor, wherein a control end of the variable resistor is connected to the controller, a first end of the variable resistor is connected to the first voltage regulating module, and a second end of the variable resistor is grounded; or A plurality of series resistors are connected to the first voltage regulating module, and each resistor is connected to a controller via a switch device to control whether the corresponding resistor is connected to the second voltage regulating module.

7. A method for measuring intraocular pressure, characterized in that: The rebound tonometer according to any one of claims 1 to 6 is used, wherein the method comprises: Regulating a first excitation voltage input to the driving coil through a power regulation module so that the probe is driven by the first excitation voltage to emit along an extension direction of the probe; During the process of the probe rebounding in the opposite direction after hitting the cornea, a first corresponding relationship between a first measurement voltage in the measuring coil and time is acquired by the controller; determining the measured parameter value of the probe at the moment of impacting the cornea through the first corresponding relationship; When the difference between the measured parameter value and the target parameter value is greater than a preset threshold, calculating a correction voltage using the difference; Correcting the first excitation voltage according to the correction voltage to obtain a target excitation voltage; When the difference between the measured parameter value and the target parameter value is less than or equal to a preset threshold, determining the first excitation voltage as a target excitation voltage; The intraocular pressure of the subject to be measured is measured according to the target excitation voltage to obtain a final measurement result of the same measurement cycle.

8. The method according to claim 7, characterized in that Measuring the intraocular pressure of the subject to be measured according to the target excitation voltage to obtain a final measurement result of the same measurement cycle includes: Regulating the voltage input to the drive coil to the target excitation voltage through the power regulation module; exciting the driving coil according to the target excitation voltage so as to cause the probe to be emitted along the extending direction of the probe; During the process of the probe rebounding in the opposite direction after striking the cornea, a target corresponding relationship between a second measurement voltage in the measurement coil and time is acquired by the controller; calculating the energy value of the probe at the moment of impacting the cornea according to the target correspondence; Calculating the intraocular pressure of the subject to be measured using the energy value at the moment of impact to obtain a single measurement result; Determine whether N measurements within the same measurement cycle are completed. If so, calculate the final measurement result based on the N single measurement results within the same measurement cycle; if not, return to stimulating the drive coil according to the target excitation voltage until N measurements within the same measurement cycle are completed; N is an integer.

9. The method according to claim 8, characterized in that Before exciting the driving coil according to the target excitation voltage to cause the probe to be launched along the probe extension direction, the method further includes: When the first excitation voltage is determined to be the target excitation voltage, the intraocular pressure of the object to be measured is calculated using the measured parameter value to obtain a single intraocular pressure measurement result, and the measurement result is recorded as the first single measurement result in the same measurement cycle.

10. The method according to claim 7, characterized in that The measured parameter value includes a measured energy value corresponding to the energy parameter, and the target parameter value includes a target energy value corresponding to the energy parameter; The first excitation voltage indicates that the driving coil launches the probe at a first time under the excitation of the first excitation voltage, and the probe passes a preset distance and strikes the cornea at a target energy value at a second time; Determining the measured parameter value of the probe at the moment of impacting the cornea through the first corresponding relationship includes: Integrating the first measured voltage corresponding to the first time to the second time according to the first corresponding relationship to determine a first displacement of the probe, where the first displacement represents a distance moved by the probe from the first time to the second time; determining a second corresponding relationship between energy and displacement based on a first corresponding relationship between the first measured voltage and time; According to the second corresponding relationship, the energy value corresponding to the first distance is determined to be the actually measured energy value when the probe hits the cornea.

11. The method according to claim 7, characterized in that The measured parameter value includes a measured speed value corresponding to the speed parameter, and the target parameter value includes a target speed value corresponding to the speed parameter, and the target parameter value is related to the human-machine distance and corneal sensitivity; The first excitation voltage indicates that the drive coil is excited by the first excitation voltage and emits at a first time, and the probe passes a preset distance and strikes the cornea at a target speed value within a second time; Determining the measured parameter value of the probe at the moment of impacting the cornea through the first corresponding relationship includes: Integrating a first measured voltage corresponding to a time period between the first time and the second time according to the first corresponding relationship to determine a first displacement of the probe, where the first displacement represents a distance moved by the probe from the first time to the second time; determining a second corresponding relationship between energy and displacement based on a first corresponding relationship between the first measured voltage and time; Determine the third correspondence between velocity and displacement by using the second correspondence between energy and displacement and the kinetic energy theorem; According to the third corresponding relationship, the speed value corresponding to the first distance is determined to be the actual speed value of the probe when it hits the cornea.

12. The method according to claim 10 or 11, characterized in that The determining a second corresponding relationship between energy and displacement by using a first corresponding relationship between the first measured voltage and time includes: determining a fourth corresponding relationship between driving force and displacement based on a first corresponding relationship between the first measured voltage and time and a force relationship of the probe; The second corresponding relationship between energy and displacement is determined through the fourth corresponding relationship between the driving force and the displacement.

13. The method according to claim 7 or 10, characterized in that When the difference between the measured parameter value and the target parameter value is greater than a preset threshold, calculating the correction voltage using the difference includes: Calculating the energy difference between the measured energy value and the target energy value; Calculating a distance difference between the first displacement and a preset distance; Calculating a corrected driving force based on the distance difference and the energy difference; The correction voltage corresponding to the correction driving force is determined using a magnetic energy formula.

14. The method according to any one of claims 7 or 11, characterized in that When the difference between the measured parameter value and the target parameter value is greater than a preset threshold, calculating the correction voltage using the difference includes: Calculating a speed difference between the measured speed value and the target speed value; Calculating the corrected energy through the speed difference; Calculating a distance difference between the first displacement and a preset distance; Calculating a corrected driving force using the distance difference and the corrected energy; The correction voltage corresponding to the correction driving force is determined by the magnetic energy formula.

15. The method according to any one of claims 7 to 14, characterized in that Before adjusting the first excitation voltage input to the driving coil by the power adjustment module so that the probe is driven by the first excitation voltage to emit along the extending direction of the probe, the method includes: A second excitation voltage is output to the measuring coil via a controller, so that the probe is pulled back to an initial position along the extending direction of the probe.

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