Automatic skiascopy optometry system and method based on reflected light velocity analysis

Abstract

The invention discloses an automatic skiascopy optometry system and method based on reflected light velocity analysis, and the system comprises an incident light plate, an automatic lens assembly, a photoelectric detection mechanism and a calculation processor, the incident light plate is used for projecting a beam of incident light band with a fixed swing speed and a fixed width to human eyes, the photoelectric detection mechanism is used for receiving a reflection light band reflected by the human eye retina and generating an electric signal. The calculation processor is configured to continuously analyze the electric signals to calculate the moving speed and direction of the reflection light band; a closed-loop feedback is executed, and as long as the moving speed is not zero, the turntable is commanded to rotate so as to change the degree of the lens; and when the moving speed is zero, rotation is stopped, and the current lens degree is output as a refraction measurement result. Unification of measurement references is guaranteed through fixed incident light band projection, and objective and accurate refraction measurement is realized through signal analysis and closed-loop feedback automatic adjustment of the lens degree by the calculation processor.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of optical measurement, in particular to an automatic phoropter system and method based on reflected light speed analysis. BACKGROUND

[0002] Optical measurement technology plays an important role in modern medicine. Accurate measurement of the refractive state and accommodation response of the human eye is crucial for diagnosing and correcting vision problems.

[0003] Currently, the techniques for measuring the refractive state of the human eye mainly fall into two categories: traditional manual phoropter and automatic phoropter.

[0004] The first category, traditional manual phoropter, has long been recognized as the "gold standard" of objective refraction in clinical practice. However, this method has obvious defects: it completely relies on the clinical experience and subjective judgment of the operator. The operator not only needs to manually shake the phoropter, but also needs to keep the shaking speed and amplitude constant; at the same time, it also needs to judge the moving direction (forward / inverse) and speed of the retinal reflected light band ("reflected light") by naked eye, especially the judgment of "neutral" state (i.e. the instantaneous flash of the reflected light filling the pupil) is easy to introduce subjective error. In addition, the operator must rely on estimation to maintain the "working distance" with the patient, and small deviations in distance will cause significant errors in the final refraction results.

[0005] The second category, automatic phoropter, is developed to solve the defects of the above-mentioned manual technique. These devices (such as Hartmann-Shack wavefront aberration, image focus method or corneal curvature measurement based devices) achieve automation, eliminating the subjective judgment and instability of the operator.

[0006] However, existing automatic phoropters also have their own technical limitations: Principle deviation: the measurement principles of these devices (such as analyzing image clarity or wavefront distortion) are completely different from the "gold standard" principle of traditional phoropter (i.e. analyzing the dynamics and speed of reflected light).

[0007] Application limitations: Many automatic phoropters rely on clear refractive media and stable fixation of patients (usually requiring chin rest), and their reliability will decrease when measuring children, uncooperative patients or eyes with turbid refractive media (such as cataract). SUMMARY

[0008] In order to solve the technical problems in the prior art, the present application provides an automatic phoropter system and method based on reflected light speed analysis.

[0009] The automatic phoropter system and method based on reflected light speed analysis provided by the present application adopts the following technical solutions: An automated retinoscopy system based on reflected light velocity analysis includes: An incident light plate is configured to project a beam of incident light with a fixed oscillation speed and a fixed width onto the human eye. An automatic lens assembly includes a positive spherical lens turntable and a negative spherical lens turntable disposed in the optical path between the incident light plate and the human eye. The positive spherical lens turntable is provided with a plurality of positive spherical lenses of different powers, and the negative spherical lens turntable is provided with a plurality of negative spherical lenses of different powers. A photoelectric detection mechanism is configured to receive the reflected light bands reflected by the retina of the human eye and generate corresponding electrical signals; A computing processor is communicatively connected to the incident light plate, the photoelectric detection mechanism, the positive spherical mirror turntable, and the negative spherical mirror turntable; The computing processor is configured to: continuously analyze the electrical signal to determine the displacement of the reflected light strip within one movement time, and calculate the moving speed and direction of the reflected light strip; and execute a closed-loop feedback, wherein, as long as the computing processor determines that the moving speed is not zero, it commands the positive spherical mirror turntable and / or the negative spherical mirror turntable to rotate to change the lens power in the optical path; until the computing processor determines that the moving speed is zero, it stops rotating and outputs the current lens power as the refractive measurement result.

[0010] In some embodiments, the automatic retinoscopy system based on reflected light velocity analysis further includes a ranging mechanism, the ranging mechanism comprising: An infrared emitter is positioned outside the main optical path of the automatic lens assembly and is configured to emit a collimated infrared beam toward the human eye. An infrared receiver, positioned at a known fixed baseline distance from the infrared emitter, includes a position-sensing surface; the computing processor is further configured to: (a) Detect the specific location of the narrow beam of infrared light reflected by the human eye (1) falling on the position sensing surface; (b) Based on the detected specific location, the working distance d of the human eye is calculated using trigonometric functions. work ; (c) The working distance d work Converted to a diopter compensation value D comp And used for the final result calculation, specifically including: According to formula D comp =1 / d work The working distance d measured by the ranging mechanism work Converted to the aforementioned refractive power compensation value D comp ; The combined lens power of the automatic lens assembly, which stops when the moving speed is zero, is determined as the total measured refractive power D. gross ; According to algorithm D final =D gross -D comp The final refractive measurement result D is calculated by subtracting the refractive error compensation value from the total measured refractive error. final .

[0011] In some embodiments, the computing processor is configured to: When it is determined that the direction of movement of the reflected light band is the same as the direction of swing of the incident light band, the positive spherical mirror rotator is commanded to rotate to adjust the degree; when it is determined that the direction of movement of the reflected light band is opposite to the direction of swing of the incident light band, the negative spherical mirror rotator is commanded to rotate to adjust the degree.

[0012] In some embodiments, the computing processor is further configured to: determine the interval size of the adjustment degree of the positive spherical mirror turntable or the negative spherical mirror turntable based on the magnitude of the determined moving speed of the reflected light band, wherein the faster the determined moving speed, the larger the interval adjustment, and the slower the determined moving speed, the smaller the interval adjustment.

[0013] In some embodiments, the automatic lens assembly further includes a cylindrical lens turntable, on which a plurality of cylindrical lenses of different powers are disposed, and the cylindrical lens turntable can be rotated to change the astigmatic axis; the computing processor is also communicatively connected to the cylindrical lens turntable; when executing the closed-loop feedback, the computing processor is further configured to: command the cylindrical lens turntable to rotate to change the astigmatic axis in the optical path; To enable astigmatic mode measurements, the computational processor is further configured to: The incident light plate is commanded to rotate the incident light band 360 degrees; During the rotation, the signal of the photoelectric detection mechanism is continuously analyzed to detect and determine the azimuth where the width of the reflected light band is the smallest, and this azimuth is determined as the first principal meridian; The rotation of the incident light plate is stopped, and the direction of its swing motion is fixed on the locked first principal meridian; The closed-loop feedback is executed, and the cylindrical lens turret is commanded to adjust the diopter to detect and determine the cylindrical lens refractive power required to neutralize the first principal meridian; The incident light plate is commanded to rotate to a second principal meridian perpendicular to the first principal meridian, and the steps of fixing the swing direction and performing closed-loop feedback are repeated to neutralize the second principal meridian.

[0014] In some embodiments, to enable the measurement of the controlled reaction mode, the method further includes: A MEM lens is disposed in the optical path; A near optotype; the computing processor is configured to, while the near optotype is being gazed upon, perform the closed-loop feedback to detect and determine a refractive power value indicating accommodative lag or lead in the human eye.

[0015] In some embodiments, the computing processor, when analyzing the electrical signal, is configured to perform calculations according to formula V. B =△ 位移 The moving speed is calculated using / △t, where △ 位移 It is the displacement of the reflected light band sensed by the photoelectric detection mechanism, and Δt is the fixed time for the incident light band projected by the incident light plate to move once.

[0016] In some embodiments, when determining the first principal meridian, the computing processor is configured to: determine the azimuth where the width of the reflected light band is minimum; and, at that azimuth, the direction of movement of the reflected light band must be parallel to the swing direction of the incident light plate.

[0017] In some embodiments, each of the positive spherical mirror turntable, the negative spherical mirror turntable, and the cylindrical mirror turntable includes: Central axis; A disk that can rotate about the central axis; Multiple lenses are arranged along the circumference of the disk body; A drive motor is provided, the drive end of which is connected to the disk body and the drive motor is electrically connected to the computing processor; wherein the computing processor controls the drive motor to drive the disk body to rotate, so as to selectively place one of the plurality of lenses in the optical path.

[0018] This application also provides an automated retinoscopy method based on reflected light velocity analysis, applicable to the aforementioned automated retinoscopy system based on reflected light velocity analysis, and includes the following steps: A beam of incident light with a fixed oscillation speed and a fixed width is projected onto the human eye through an incident light plate; A photoelectric detection mechanism receives the reflected light band from the human eye's retina and generates an electrical signal; A computing processor continuously analyzes the electrical signal to determine the displacement of the reflected light strip within one movement time and calculates the moving speed of the reflected light strip. As long as the computing processor determines that the moving speed is not zero, it commands the positive spherical lens turntable or the negative spherical lens turntable to rotate according to whether the determined direction is forward or backward, so as to change the lens power; until the computing processor analyzes and determines that the moving speed is zero, it stops the rotation and outputs the current combined power of the positive spherical lens turntable or the negative spherical lens turntable as the detected human eye spherical refractive error.

[0019] In summary, this application includes at least one of the following beneficial technical effects: 1. This application uses a photoelectric detection mechanism to receive retinal reflected light and generate an electrical signal. The computing processor continuously analyzes the signal to determine the moving speed and direction of the reflected light band. Through closed-loop feedback, it automatically commands the positive and negative spherical mirror turntables to rotate and adjust the degree until the processor determines that the moving speed of the reflected light is zero, thereby outputting an objective measurement result. 2. The system projects an incident light band with a "fixed swing speed and fixed width" through an incident light plate, solving the problem of inconsistent speed and amplitude when manually shaking the retinoscope. The system includes a ranging mechanism that uses an infrared transmitter and an infrared receiver to calculate the precise working distance of the human eye using trigonometric functions, converts it into a refractive error compensation value, and finally subtracts the compensation value from the total measurement value, overcoming the shortcomings of traditional methods that rely on estimating the working distance and thus leading to incorrect results. 3. To improve efficiency, the processor determines the "interval adjustment size" of the lens power based on the "movement speed" of the measured reflected light band. The faster the speed, the larger the adjustment step, and vice versa. To measure astigmatism, a cylindrical lens turret is added to the system, and the processor commands the incident light plate to rotate the incident light band 360 degrees. During this process, the signal is continuously analyzed to automatically detect and determine the "azimuth where the width of the reflected light band is the smallest" as the first principal meridian. Subsequently, the direction is automatically fixed and the two principal meridians are neutralized respectively, solving the problem of time-consuming and experience-dependent manual search for the astigmatism axis. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of an automatic retinoscopy system based on reflected light velocity analysis provided in an embodiment of this application; Figure 2 This is a schematic diagram of the device appearance according to an embodiment of this application; Figure 3 This is a schematic diagram of the device's human-machine interface and usage status according to an embodiment of this application; Explanation of reference numerals in the attached diagram: 1. Human eye; 2. Incident light plate; 3. Automatic lens assembly; 31. Positive spherical mirror turntable; 32. Negative spherical mirror turntable; 33. Cylindrical mirror turntable; 34. MEM lens; 4. Photoelectric detection mechanism; 41. Photoelectric sensor; 42. Signal conversion circuit; 5. Calculation processor; 6. Distance measuring mechanism; 61. Infrared transmitter; 62. Infrared receiver; 7. Human-computer interaction interface; 71. Spherical mirror mode button; 72. Astigmatism mode button; 73. Forward button; 74. Near-field optotype. Detailed Implementation

[0021] The technical solutions in the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. The described embodiments are only possible technical implementations of the present invention, but are not limited thereto. Other embodiments obtained by those skilled in the art in conjunction with the embodiments of the present invention without creative effort are also within the protection scope of the present invention.

[0022] This application mainly adopts a fixed light strip projection and closed-loop feedback adjustment lens power scheme, which achieves objective, accurate and efficient refraction. The following is a further detailed description of this application.

[0023] Example 1 Please refer to Figure 1 The automatic retinoscopy system based on reflected light velocity analysis provided in this application includes an incident light plate 2, an automatic lens assembly 3, a photoelectric detection mechanism 4, and a computing processor 5. The incident light plate 2 projects an incident light band with a fixed oscillation speed and fixed width onto the human eye 1. The automatic lens assembly 3 is positioned in the optical path between the incident light plate 2 and the human eye 1. The photoelectric detection mechanism 4 receives the reflected light band from the retina of the human eye 1 and generates an electrical signal. The computing processor 5 is communicatively connected to the incident light plate 2, the photoelectric detection mechanism 4, and the automatic lens assembly 3, performing closed-loop feedback to adjust the lens power until the reflected light band's movement speed is zero, outputting the refractive measurement result. This achieves the effect of objectively and accurately measuring the refractive state of the human eye 1. This is because the fixed oscillation speed and width of the incident light band ensures a consistent measurement benchmark, and the closed-loop feedback mechanism automatically adjusts the lens power, avoiding subjective judgment errors.

[0024] Specifically, the incident light plate 2 includes a light source and a light band adjustment device. The light source can be a light-emitting diode (LED) or a laser light source. LEDs have the advantages of low power consumption and long lifespan, while laser light sources have the characteristics of high brightness and high directionality. The light band adjustment device can be a grating or a liquid crystal light valve. The grating forms a light band with a fixed width and oscillation speed by controlling the width and oscillation speed of the light-transmitting slit, while the liquid crystal light valve can adjust the characteristics of the light band by changing the arrangement of liquid crystal molecules. After the light emitted by the light source passes through the light band adjustment device, it forms an incident light band with a fixed oscillation speed and fixed width, which is projected onto the human eye 1.

[0025] The automatic lens assembly 3 includes a positive spherical mirror turntable 31 and a negative spherical mirror turntable 32. The positive spherical mirror turntable 31 includes a central axis, a disk body rotatable around the central axis, multiple positive spherical mirrors of different powers, and a drive motor. The central axis supports and positions the disk body, which can be made of aluminum alloy, offering advantages of light weight and high strength. Multiple positive spherical mirrors of different powers are arranged along the circumference of the disk body. The drive end of the drive motor is connected to the disk body. The computing processor 5 controls the drive motor to rotate the disk body, selectively placing one of the multiple positive spherical mirrors in the optical path.

[0026] The structure of the negative spherical lens turntable 32 is similar to that of the positive spherical lens turntable 31, except that it is equipped with multiple negative spherical lenses of different powers.

[0027] The photoelectric detection mechanism 4 includes a photoelectric sensor 41 and a signal conversion circuit 42. The photoelectric sensor 41 can be a photodiode or a phototransistor. Photodiodes have the advantages of fast response speed and high sensitivity, while phototransistors have higher gain. The signal conversion circuit 42 converts the optical signal received by the photoelectric sensor 41 into an electrical signal and transmits it to the computing processor 5.

[0028] The computing processor 5 can be a microcontroller, a programmable logic controller (PLC), or an industrial computer. Microcontrollers are characterized by their small size and low cost, making them suitable for small devices; programmable logic controllers have the advantages of high reliability and strong anti-interference capabilities, and are often used in industrial control fields; while industrial computers have powerful computing and data processing capabilities.

[0029] The computing processor 5 is configured to continuously analyze the electrical signals transmitted from the photoelectric detection mechanism 4, according to formula V. B =△ 位移 / △t is used to calculate the moving speed V of the reflected light band. B , where △ 位移 Δt is the displacement of the reflected light band sensed by the photoelectric detection mechanism 4, and Δt is the fixed time for the incident light band projected by the incident light plate 2 to move once. As long as the calculation processor 5 determines that the moving speed is not zero, it commands the positive spherical mirror turntable 31 and / or the negative spherical mirror turntable 32 to rotate to change the lens power in the optical path. When it is determined that the moving direction of the reflected light band is the same as the swing direction of the incident light band (forward movement), the positive spherical mirror turntable 31 is commanded to rotate to adjust the power; when it is determined that the moving direction of the reflected light band is opposite to the swing direction of the incident light band (backward movement), the negative spherical mirror turntable 32 is commanded to rotate to adjust the power.

[0030] Meanwhile, the computing processor 5 also determines the interval (step value) of adjusting the degrees of the positive spherical mirror turntable 31 or the negative spherical mirror turntable 32 according to the speed at which the reflected light band moves. The faster the movement speed, the larger the interval adjustment, and the slower the movement speed, the smaller the interval adjustment, which can improve the neutralization efficiency.

[0031] The system also includes a ranging mechanism 6, which comprises an infrared emitter 61 and an infrared receiver 62. The infrared emitter 61 is positioned outside the main optical path of the automatic lens assembly 3 and emits a collimated beam of infrared light toward the human eye 1. The infrared receiver 62 is positioned at a known fixed baseline distance from the infrared emitter 61 and includes a position-sensing surface. The computational processor 5 detects the specific position of the narrow beam of infrared light reflected from the human eye 1 falling on the position-sensing surface, and calculates the working distance d of the human eye 1 using trigonometric functions based on this detected position. work The working distance d work Converted to a diopter compensation value D comp And used for the final result calculation.

[0032] Specifically, this includes according to formula D. comp =1 / d work The working distance d measured by the ranging mechanism 6 work Converted to refractive power compensation value D comp The total measured refractive power D is determined by the combined lens power of the automatic lens assembly 3 when it stops moving at zero speed. gross According to formula D final =D gross -D comp The final refractive measurement result D is calculated by subtracting the refractive error compensation value from the total measured refractive error. final .

[0033] Preferably, the automatic lens assembly 3 further includes a cylindrical lens turntable 33, which includes a central axis, a disk body rotatable about the central axis, multiple cylindrical lenses of different powers, and a drive motor. The central axis serves to support and position the disk body, which can be made of plastic, resulting in lower cost. The multiple cylindrical lenses of different powers are arranged along the circumference of the disk body. The drive end of the drive motor is connected to the disk body. The computing processor 5 controls the drive motor to drive the disk body to rotate, selectively placing one of the multiple cylindrical lenses in the optical path. The cylindrical lens turntable 33 can also be rotated to change the astigmatic axis.

[0034] To achieve astigmatism mode measurement, the computational processor 5 commands the incident light plate 2 to rotate the light band 360 degrees. During the rotation, the signal from the photodetector 4 is continuously analyzed to detect and determine the azimuth where the width of the reflected light band is minimized. At this azimuth, the direction of movement of the reflected light band must be parallel to (i.e., in the same or opposite direction) the swing direction of the incident light band. This azimuth is designated as the first principal meridian. Then, the rotation of the incident light plate 2 is stopped, and its swing direction is fixed on the locked first principal meridian. Closed-loop feedback is executed, and the cylinder mirror 33 is commanded to adjust its degree to detect and determine the cylinder refractive power required to neutralize the first principal meridian. Next, the incident light plate 2 is commanded to rotate to the second principal meridian, which is perpendicular to the first principal meridian, and the steps of fixing the swing direction and executing closed-loop feedback are repeated to neutralize the second principal meridian.

[0035] In this embodiment, the addition of the cylindrical lens rotatable disk 33 enables the system to measure astigmatism. By rotating the incident light band 360 degrees and using dual standards to determine the first principal meridian, and then neutralizing the first and second principal meridians respectively, the degree and axis of astigmatism can be accurately measured, further expanding the system's functionality and improving the comprehensiveness and accuracy of refraction.

[0036] Please refer to Figure 2 and Figure 3 The system also includes a human-computer interaction interface 7, which includes a spherical lens mode button 71, an astigmatism mode button 72, and a forward button 73. The spherical lens mode button 71 commands the computational processor 5 to perform measurements based on the reflected light's forward or reverse movement, controlling the positive or negative spherical lens turntable 31 and 32 respectively. The astigmatism mode button 72 commands the computational processor 5 to perform astigmatism mode measurements, including rotating the incident light band to determine the principal meridian. The forward button 73 commands the computational processor 5 to begin repeating the measurement process for the other eye after completing the measurement for one eye.

[0037] Preferably, please refer to Figure 3 To achieve Monocular Estimate Method (MEM) mode measurement, the automated lens assembly 3 further includes a dedicated MEM lens 34, and the human-computer interface 7 includes a near target card 74. The MEM lens 34 is positioned in the optical path. When the operator selects the MEM mode (e.g., by activating the near target card 74), the patient is instructed to fixate on the near target card 74. At this time, the computational processor 5 is configured to execute the closed-loop feedback, automatically adjusting the lenses (e.g., the MEM lens 34, or the positive spherical mirror rotator 31 and the negative spherical mirror rotator 32) until the reflected light velocity is zero, thereby detecting and determining the refractive power value of the human eye 1 in near fixation state that indicates lag or advance in accommodation response.

[0038] The implementation principle of this embodiment is as follows: The automatic retinoscopy system provides a standardized incident light band through the incident light plate 2. The photoelectric detection mechanism 4 receives the reflected light band and converts it into an electrical signal. The computing processor 5 analyzes and processes the electrical signal and automatically adjusts the lens power through a closed-loop feedback mechanism. At the same time, the ranging mechanism 6 realizes automatic compensation of the working distance, and the human-machine interface 7 facilitates operation. Compared with the prior art, this system not only overcomes the problems of traditional manual retinoscopy technology, such as reliance on subjective experience, non-standard shaking speed, inaccurate estimation of working distance, difficulty in finding the axis, and easy error in the results; but also, its core measurement principle of "based on reflected light velocity analysis" is different from the principle of existing automatic computer retinoscopy instruments (such as those based on image focus method or wavefront distortion analysis). This embodiment provides a new technical solution based on the classic retinoscopy principle of automation, realizing objective and standardized retinoscopy.

[0039] Example 2 Please refer to Figure 1 The automatic retinoscopy method based on reflected light velocity analysis provided in this application includes the following steps: S1, a beam of incident light with a fixed oscillation speed and fixed width is projected onto the human eye 1 through the incident light plate 2. In this step, the device used is the incident light plate 2, whose light source can be a light-emitting diode or a laser source, and the light band adjustment device can be a grating or a liquid crystal light valve. During operation, the power to the incident light plate 2 is turned on, and the light band adjustment device is adjusted to emit an incident light band with a fixed oscillation speed and fixed width.

[0040] S2, a photoelectric detection mechanism 4 receives the reflected light band passing through the retina of the human eye 1 and generates an electrical signal. The photoelectric detection mechanism 4 can be a photodiode or a phototransistor, placed in a suitable position to receive the reflected light band. When the reflected light band shines on the photoelectric detection mechanism 4, the photoelectric detection mechanism 4 converts the light signal into an electrical signal.

[0041] S3, a computing processor 5 continuously analyzes the electrical signal to determine the displacement of the reflected light strip within one movement time and calculates the moving speed of the reflected light strip. The computing processor 5 can be a microcontroller, a programmable logic controller, or an industrial computer. It receives the electrical signal from the photoelectric detection mechanism 4 and calculates the speed according to formula V. B =△ 位移 / △t Calculate the moving speed V of the reflected light band B , where △ 位移 Δt is the displacement of the reflected light band sensed by the photoelectric detection mechanism 4, and Δt is the fixed time for the incident light band projected by the incident light plate 2 to move once.

[0042] S4. Once the processor 5 determines that the moving speed is not zero, it commands the positive spherical mirror turntable 31 or the negative spherical mirror turntable 32 to rotate, depending on whether the determined direction is forward or reverse, to change the lens power. When the moving direction of the reflected light band is determined to be the same as the swing direction of the incident light band (forward), the positive spherical mirror turntable 31 is commanded to rotate, increasing the positive power; when the moving direction of the reflected light band is determined to be opposite to the swing direction of the incident light band (reverse), the negative spherical mirror turntable 32 is commanded to rotate, increasing the negative power. Simultaneously, the processor 5 also determines the interval size of the power adjustment based on the moving speed of the reflected light band; the faster the moving speed, the larger the interval adjustment, and the slower the moving speed, the smaller the interval adjustment. S5. Until the processor 5 analyzes and determines that the moving speed is zero, it stops rotating and outputs the current combined power of the positive spherical mirror turntable 31 or the negative spherical mirror turntable 32 as the detected spherical refractive error of the human eye.

[0043] The implementation principle of this embodiment is as follows: This automated retinoscopy method achieves objective and accurate measurement of human eye spherical refractive error through standardized light band projection, reception and analysis of reflected light bands, and automatic adjustment of lens power. Compared with traditional manual retinoscopy methods, this method avoids subjective judgment errors and operational complexity. More importantly, the technical concept of "based on reflected light velocity analysis" embodied in this method provides a new automated measurement approach different from existing automated computer refractometers (such as those based on image focus analysis). By automating the classic retinoscopy principle, it improves the efficiency and accuracy of refraction.

[0044] The specific embodiments described above do not constitute a limitation on the scope of protection of this application. Any other corresponding changes and modifications made based on the technical concept of this application should be included within the scope of protection of this application.

Claims

1. An automated retinoscopy system based on reflected light velocity analysis, characterized in that, include: An incident light plate (2) is configured to project an incident light band with a fixed oscillation speed and a fixed width onto the human eye (1); An automatic lens assembly (3) includes a positive spherical lens turntable (31) and a negative spherical lens turntable (32) disposed in the optical path between the incident light plate (2) and the human eye (1). The positive spherical lens turntable (31) is provided with a plurality of positive spherical lenses of different powers, and the negative spherical lens turntable (32) is provided with a plurality of negative spherical lenses of different powers. A photoelectric detection mechanism (4) is configured to receive the reflected light band reflected by the retina of the human eye (1) and generate a corresponding electrical signal; The computing processor (5) is communicatively connected to the incident light plate (2), the photoelectric detection mechanism (4), the positive spherical mirror turntable (31), and the negative spherical mirror turntable (32); The computing processor (5) is configured to: continuously analyze the electrical signal to determine the displacement of the reflected light strip within one movement time, and calculate the moving speed and direction of the reflected light strip; and execute a closed-loop feedback, wherein, as long as the computing processor (5) determines that the moving speed is not zero, it commands the positive spherical mirror turntable (31) and / or the negative spherical mirror turntable (32) to rotate to change the lens power in the optical path; The rotation stops when the calculation processor (5) determines that the moving speed is zero, and the current lens power is output as the refractive measurement result.

2. The automatic retinoscopy system based on reflected light velocity analysis according to claim 1, characterized in that, It also includes a ranging mechanism (6), which comprises: An infrared emitter (61) is positioned outside the main optical path of the automatic lens assembly (3) and configured to emit a collimated infrared beam toward the human eye (1); An infrared receiver (62) is positioned at a known fixed baseline distance from the infrared emitter (61), the infrared receiver (62) including a position-sensing surface; the computing processor (5) is further configured to: (a) Detect the specific location of the narrow beam of infrared light reflected by the human eye (1) falling on the position sensing surface; (b) Based on the detected specific location, the working distance d of the human eye (1) is calculated using trigonometric functions. work ; (c) The working distance d work Converted to a diopter compensation value D comp And used for the final result calculation, specifically including: According to formula D comp =1 / d work The working distance d measured by the ranging mechanism (6) work Converted to the aforementioned refractive power compensation value D comp ; The combined lens power of the automatic lens assembly (3) that stops when the moving speed is zero is determined as the total measured refractive power D. gross ; According to algorithm D final =D gross -D comp The final refractive measurement result D is calculated by subtracting the refractive error compensation value from the total measured refractive error. final .

3. The automatic retinoscopy system based on reflected light velocity analysis according to claim 1, characterized in that, When executing the closed-loop feedback, the computing processor (5) is configured to: When it is determined that the direction of movement of the reflected light band is the same as the direction of swing of the incident light band, the positive spherical mirror turntable (31) is ordered to rotate to adjust the degree; when it is determined that the direction of movement of the reflected light band is opposite to the direction of swing of the incident light band, the negative spherical mirror turntable (32) is ordered to rotate to adjust the degree.

4. The automatic retinoscopy system based on reflected light velocity analysis according to claim 1, characterized in that, The computing processor (5) is further configured to determine the interval size of the adjustment degree of the positive spherical mirror turntable (31) or the negative spherical mirror turntable (32) according to the determined moving speed of the reflected light band, wherein the faster the determined moving speed, the larger the interval adjustment, and the slower the determined moving speed, the smaller the interval adjustment.

5. The automatic retinoscopy system based on reflected light velocity analysis according to claim 1, characterized in that, The automatic lens assembly (3) also includes a cylindrical lens turntable (33), on which multiple cylindrical lenses of different powers are provided, and the cylindrical lens turntable (33) can be rotated to change the astigmatic axis; the computing processor (5) is also communicatively connected to the cylindrical lens turntable (33); when executing the closed-loop feedback, the computing processor (5) is also configured to: command the cylindrical lens turntable (33) to rotate to change the astigmatic axis in the optical path; To enable astigmatic mode measurement, the computational processor (5) is further configured as follows: The incident light plate (2) is ordered to rotate the incident light strip 360 degrees; During the rotation, the signal of the photoelectric detection mechanism (4) is continuously analyzed to detect and determine the azimuth where the width of the reflected light band is the smallest, and the azimuth is determined as the first principal meridian; The rotation of the incident light plate (2) is stopped, and the direction of its swing motion is fixed on the locked first principal meridian; The closed-loop feedback is executed, and the cylindrical lens turret (33) is commanded to adjust the diopter to detect and determine the cylindrical lens refractive power required to neutralize the first principal meridian; The incident light plate (2) is commanded to rotate to the second principal meridian perpendicular to the first principal meridian, and the steps of fixing the swing direction and performing closed-loop feedback are repeated to neutralize the second principal meridian.

6. The automatic retinoscopy system based on reflected light velocity analysis according to claim 1, characterized in that, To enable the measurement of the controlled reaction mode, the following is also included: A MEM lens (34) is disposed in the optical path; A near target card (74); the computing processor (5) is configured to detect and determine the refractive power value of the human eye (1) that is lagging or leading in accommodation response when the near target card (74) is being gazed upon by performing the closed-loop feedback.

7. The automatic retinoscopy system based on reflected light velocity analysis according to claim 1, characterized in that, When analyzing the electrical signal, the computing processor (5) is configured to perform calculations according to formula V. B =△ 位移 The moving speed V is calculated using / △t. B , where △ 位移 Δt is the displacement of the reflected light band sensed by the photoelectric detection mechanism (4), and Δt is the fixed time for the incident light band projected by the incident light plate (2) to move once.

8. The automatic retinoscopy system based on reflected light velocity analysis according to claim 5, characterized in that, When determining the first principal meridian, the computing processor (5) is configured to: determine the azimuth where the width of the reflected light band is the smallest; and, at this azimuth, the direction of movement of the reflected light band must be parallel to the swing direction of the incident light plate (2).

9. The automatic retinoscopy system based on reflected light velocity analysis according to claim 5, characterized in that, Each of the positive spherical mirror turntable (31), the negative spherical mirror turntable (32), and the cylindrical mirror turntable (33) includes: Central axis; A disk that can rotate about the central axis; Multiple lenses are arranged along the circumference of the disk body; A drive motor is connected to the disk body at its drive end and is electrically connected to the computing processor (5); wherein the computing processor (5) controls the drive motor to drive the disk body to rotate so as to selectively place one of the plurality of lenses in the optical path.

10. An automated retinoscopy method based on reflected light velocity analysis, characterized in that, The automatic retinoscopy system based on reflected light velocity analysis as described in any one of claims 1-9 is applicable and includes the following steps: A beam of incident light with a fixed swing speed and fixed width is projected onto the human eye (1) through the incident light plate (2); A photoelectric detection mechanism (4) receives the reflected light band through the retina of the human eye (1) and generates an electrical signal; The electrical signal is continuously analyzed by a computing processor (5) to determine the displacement of the reflected light strip within one movement time and to calculate the moving speed of the reflected light strip. As long as the computing processor (5) determines that the moving speed is not zero, it commands the positive spherical mirror turntable (31) or the negative spherical mirror turntable (32) to rotate according to whether the determined direction is forward or backward, so as to change the lens power. The rotation stops when the calculation processor (5) analyzes and determines that the moving speed is zero, and outputs the current combined diopter of the positive spherical mirror turntable (31) or the negative spherical mirror turntable (32) as the detected human eye spherical refractive error.

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