TWI822556B - Corneal curvature measurement system and measurement method - Google Patents

Abstract

The invention includes a near-infrared light generator, a displacement focus meter, an image detector, a first optical axis, a second optical axis and a third optical axis. The near-infrared light generator emits a beam image along the first optical axis. The beam image is first reflected to the third optical axis and then to the second optical axis. Then, the penetration displacement focal length meter is illuminated behind one eye at a certain position. , when reflected along the original path and then focused to the image detector, there is a first distance between the positioning point and the first focus of the displacement focus meter. When the fine-tuning displacement focus meter moves a second distance relative to the eye, if the beam image is also focused to the image detector, then the sum of the first and second distances is exactly the curvature radius of the eye. This case is both very convenient for estimating the corneal curvature radius from the clarity of the beam image, and the device is simple, low-cost and easy to operate.

Description

Corneal curvature measurement system and measurement method

The present invention relates to a corneal curvature measuring system and a measuring method thereof. In particular, it is particularly convenient to calculate the corneal curvature radius from the clarity of the beam image after the reference wavefront matches the wavefront to be measured. The device is simple and convenient. A low-cost and easy-to-operate corneal curvature measurement system and its measurement method.

Before eye surgery, it is very important to measure and check the corneal surface (ie, corneal curvature). Some patients may find that cataract is not the main problem after measuring and checking their corneal curvature before being referred for cataract surgery, because the problem of corneal curvature (such as keratoconus) (which is the main problem) is more serious than cataract.

During corneal curvature measurement and examination, additional clinical clues may be obtained to help you identify more subtle corneal degeneration, such as basement membrane dystrophy. The aforementioned clinical clues may be easily overlooked because they are difficult to identify through slit lamp examination. Therefore, even if the patient's vision may improve after cataract removal, the aforementioned corneal problems still exist, which may still affect postoperative vision.

In addition, corneal curvature measurement is also important for wearing contact lenses (especially rigid oxygen-permeable lenses), monitoring corneal pathology, and identifying keratoconus.

Most of the known electronic optometry instruments are expensive and require dedicated personnel to conduct testing in a dedicated place, which is troublesome and inconvenient.

So far, there is no simple device that can obtain the aforementioned clinical clues through corneal curvature measurement.

In view of this, it is necessary to develop technology that can solve the above conventional shortcomings.

The purpose of the present invention is to provide a corneal curvature measurement system and a measurement method thereof, which are very convenient for estimating the corneal curvature radius from the clarity of the beam image, and are simple, low-cost and easy to install. Operational advantages. In particular, the problem to be solved by the present invention is that corneal curvature measurement is very important for wearing contact lenses, monitoring corneal pathology, and identifying keratoconus. However, most of the known electronic corneal testing instruments are expensive and require dedicated personnel to perform testing in a dedicated place. , troublesome and inconvenient. And so far, there is no simple device that can obtain the aforementioned clinical clues through corneal curvature measurement.

The technical means to solve the above problems is to provide a corneal curvature measurement system and a measurement method. The measurement system includes: a near-infrared light generator for emitting a first light along a first optical axis. beam, and can adjust the intensity of the first beam, which is near-infrared light; a near-infrared light intensity detector is provided corresponding to the near-infrared light generator and is located on the first optical axis ; A first spectroscope is located between the near-infrared light generator and the near-infrared light intensity detector and is located on the first optical axis; a displacement focus meter is located on a second light On the axis, the second optical axis is parallel to the first optical axis; the displacement focal length meter is provided with a measurement area, and the measurement area is located on the second optical axis; a second spectroscope is located on On the second optical axis, the displacement focus meter is between the measurement area and the second beam splitter; and the first beam splitter and the second beam splitter are both located on a third optical axis. , the third optical axis and the first optical axis are perpendicular to each other, and the third optical axis and the second optical axis are perpendicular to each other; a visual mark generator is arranged on a second optical axis, The second spectroscope is between the displacement focus meter and the visual target generator; the visual target generator is used to emit a visible light visual target toward the second spectroscope, and the visible light visual target can penetrate The second spectroscope and the displacement focus meter illuminate the measurement area; and an image detector is provided corresponding to the first spectroscope and is located on the third optical axis. The first spectroscope is between the second beam splitter and the image detector; Thereby, the first beam is partially reflected and partially penetrated after irradiating the first beam splitter; after being partially reflected, it becomes a second beam, and the second beam is irradiated to the second beam splitter along the third optical axis. And reflected into a third beam, the third beam passes through the displacement focus meter along the second optical axis to become a fourth beam, and the fourth beam is irradiated to the measurement area; and, the first beam After being irradiated to the first beam splitter, it is partially penetrated into a fifth beam, and the fifth beam is irradiated to the near-infrared light intensity detector; and, after the fourth beam is irradiated to the measurement area, it is irradiated along the The second optical axis is reflected into a sixth light beam. The sixth light beam passes through the displacement focus meter and becomes a seventh light beam. The seventh light beam irradiates the second beam splitter and is reflected into an eighth light beam. The eighth light beam The light beam is irradiated to the first beam splitter along the third optical axis, and passes through the first beam splitter to become a ninth light beam. The ninth light beam is irradiated to the image detector and becomes a tenth light beam.

Regarding the measurement method, it includes the following steps: 1. Preparation step; 2. Focus confirmation step; 3. System calibration step; and 4. Actual measurement step.

The above objects and advantages of the present invention can be easily understood from the following detailed description of selected embodiments and the accompanying drawings.

The present invention is described in detail below with the following examples and drawings:

10: Near infrared light generator

20: Near infrared light intensity detector

30: First beam splitter

40: Displacement focal length meter

50: Second beam splitter

60: Optotype generator

61: Visible light sight mark

70:Image detector

71: Near infrared light filter

72: Convex lens lens

73:Light sensing device

91: Plane reflector

92: Convex optical reflective lens

93: Fixed bracket

94:Testee

941:Eye

M: Measurement area

A1: first optical axis

A2: Second optical axis

A3: The third optical axis

L1: first beam

L2: Second beam

L3: The third beam

L4: The fourth beam

L5: The fifth beam

L6: The sixth beam

L7: The seventh beam

L8: The eighth beam

L9: The ninth beam

L10: The tenth beam

S1: Preparatory steps

S2: Focus confirmation step

S3: System calibration steps

S4: Actual measurement steps

P1: first position

P2: second position

P3: Focus position

P4: Test position

P5: Focal length position

F1: First focus

F2: anchor point

F3: Second focus

R1: first distance

R2: second distance

Figure 1 is a schematic diagram of an embodiment of the present invention.

Figure 2 is a schematic diagram of one of the measurement processes of the present invention.

Figure 3 is a schematic diagram of the second measurement process of the present invention.

Figure 4 is a schematic diagram of the third measurement process of the present invention.

Figure 5 is a schematic diagram of the fourth measurement process of the present invention.

Figure 6 is a partially enlarged schematic diagram of the measurement process of Figure 5 .

Figure 7 is a partially enlarged schematic diagram of the corresponding relationship between the near-infrared light generator and the first beam of the present invention.

Figure 8 is a schematic diagram of an application example of the optotype generator and the visible light optotype of the present invention.

Figure 9 is a flow chart of the measurement method of the present invention.

Referring to Figure 1, the present invention is a corneal curvature measurement system and its measurement method. The measurement system includes: a near-infrared light generator 10 for emitting light along a first optical axis A1. A first beam L1 (as shown in Figure 2), and the intensity of the first beam L1 can be adjusted. The first beam L1 is near-infrared light.

A near-infrared light intensity detector 20 is provided corresponding to the near-infrared light generator 10 and is located on the first optical axis A1.

A first beam splitter 30 is provided between the near-infrared light generator 10 and the near-infrared light intensity detector 20 and is located on the first optical axis A1.

A displacement focal length meter 40 is located on a second optical axis A2, and the second optical axis A2 is parallel to the first optical axis A1. The displacement focal length meter 40 is provided with a measurement area M. Area M is located on the second optical axis A2.

A second spectroscope 50 is disposed on the second optical axis A2, and the displacement focus meter 40 is between the measurement area M and the second spectroscope 50. In addition, the first beam splitter 30 and the second beam splitter 50 are both located on a third optical axis A3, the third optical axis A3 is perpendicular to the first optical axis A1, and the third optical axis A3 is perpendicular to the second optical axis A2.

An optotype generator 60 is disposed on a second optical axis A2, and the second spectroscope 50 is between the displacement focus meter 40 and the optotype generator 60; the optotype generator 60 is For emitting a visible light target 61 toward the second beam splitter 50 (refer to Figure 5, and as shown in Figure 8, the visible light target is exemplified The center of 61 is a focus point; of course it can also be changed to other patterns), the visible light sight mark 61 can penetrate the second spectroscope 50 and the displacement focus meter 40 and illuminate the measurement area M.

An image detector 70 is provided corresponding to the first beam splitter 30 and is located on the third optical axis A3. The first beam splitter 30 is between the second beam splitter 50 and the image detector 70 between.

Thereby, after the first beam L1 irradiates the first beam splitter 30 (as shown in Figure 2), it is partially reflected and partially penetrated; after partial reflection, it becomes a second beam L2, and the second beam L2 is along the The third optical axis A3 irradiates the second beam splitter 50 and is reflected into a third light beam L3. The third light beam L3 passes through the displacement focus meter 40 along the second optical axis A2 and becomes a fourth light beam L4. , the fourth light beam L4 is irradiated to the measurement area M; and, the first light beam L1 is irradiated to the first beam splitter 30 and then partially penetrates to become a fifth light beam L5, and the fifth light beam L5 is irradiated to the Near-infrared light intensity detector 20.

Moreover, after the fourth light beam L4 irradiates the measurement area M, it is reflected along the second optical axis A2 to become a sixth light beam L6 (as shown in Figure 3). The sixth light beam L6 passes through the displacement type The focal length meter 40 becomes a seventh light beam L7. The seventh light beam L7 irradiates the second beam splitter 50 and is reflected into an eighth light beam L8. The eighth light beam L8 irradiates the first light beam along the third optical axis A3. The beam splitter 30 passes through the first beam splitter 30 and becomes a ninth light beam L9. The ninth light beam L9 is irradiated to the image detector 70 and becomes a tenth light beam L10.

In practice, the first beam L1 can be one of a cross mark beam (as shown in Figure 7) or a meter mark beam.

The wavelength of the first light beam L1 can be between 860nm and 1100nm (preferably), and 980nm is the best.

The near-infrared light intensity detector 20 is used to detect the intensity of the fifth light beam L5 transformed from the first light beam L1, and when the fifth light beam L5 is too strong, it passes through the near-infrared light generator 10 The intensity of the first light beam L1 is weakened to prevent irradiation damage to the eye 941 .

In addition, if the eye (that is, the eye 941) is irradiated with high-energy near-infrared light (that is, the first beam L1) for a long time, it may cause damage to the crystallin protein in the lens. Therefore, this case is provided with the near-infrared light intensity detector 20 for detecting the intensity of the fifth beam L5, which can then be adjusted by the near-infrared light generator 10 to generate the lowest but operable near-infrared light (also That is, the first light beam L1); Furthermore, this case specifically limits the irradiation time (and detection time) to be shortened to within a few seconds, which can significantly reduce the irradiation energy. In addition, the near-infrared light band in this case is selected in a better range between 860nm and 1100nm, which can also reduce the chance of causing damage to the lens protein.

The first beam splitter 30 has a structure that partially reflects and partially transmits near-infrared light.

The second beam splitter 50 has a structure that reflects near-infrared light but transmits visible light.

The image detector 70 may include a near-infrared light filter 71 , a convex lens sheet 72 and a light sensing device 73 .

The near-infrared light filter 71 is used to filter the chaotic light waves of the ninth light beam L9.

The convex lens sheet 72 is used to converge the ninth light beam L9 into the tenth light beam L10.

The light sensing device 73 is used to receive the tenth light beam L10.

The light sensing device 73 can be a near-infrared light image capturing device (such as a camera or video camera).

Referring to Figure 9, the part about the corneal curvature measurement method can include the following steps after starting:

1. Preparation step S1: Refer to Figure 1 and prepare a near-infrared light generator 10, a near-infrared light intensity detector 20, a first spectroscope 30, a displacement focus meter 40, and a second spectroscope 50 , an optotype generator 60 and an image detector 70 . The near-infrared light generator 10 is used to emit a first beam L1 (as shown in Figure 2) along a first optical axis A1, and can adjust the intensity of the first beam L1. The first beam L1 is Near infrared light. The near-infrared light intensity detector 20 is provided corresponding to the near-infrared light generator 10 and is located on the first optical axis A1. The first beam splitter 30 is disposed between the near-infrared light generator 10 and the near-infrared light intensity detector 20 and is located on the first optical axis A1. The displacement focal length meter 40 series Located on a second optical axis A2, the second optical axis A2 is parallel to the first optical axis A1; the displacement focus meter 40 is provided with a measurement area M, and the measurement area M is located on the second optical axis A1. On axis A2. The second spectroscope 50 is disposed on the second optical axis A2, and the displacement focus meter 40 is between the measurement area M and the second spectroscope 50. In addition, the first beam splitter 30 and the second beam splitter 50 are both located on a third optical axis A3, the third optical axis A3 is perpendicular to the first optical axis A1, and the third optical axis A3 is perpendicular to the second optical axis A2. The optotype generator 60 is disposed on a second optical axis A2, and the second beam splitter 50 is between the displacement focus meter 40 and the optotype generator 60; the optotype generator 60 is A visible light target 61 is emitted toward the second spectroscope 50 (refer to Figure 5, and as shown in Figure 8, for example, the center of the visible light target 61 is a focus point; of course, it can also be changed to other patterns) , the visible light sight mark 61 can penetrate the second spectroscope 50 and the displacement focus meter 40 and illuminate the measurement area M. The image detector 70 is provided corresponding to the first beam splitter 30 and is located on the third optical axis A3. The first beam splitter 30 is between the second beam splitter 50 and the image detector 70. between. Thereby, after the first beam L1 irradiates the first beam splitter 30 (as shown in Figure 2), it is partially reflected and partially penetrated; after partial reflection, it becomes a second beam L2, and the second beam L2 is along the The third optical axis A3 irradiates the second beam splitter 50 and is reflected into a third light beam L3. The third light beam L3 passes through the displacement focus meter 40 along the second optical axis A2 and becomes a fourth light beam L4. , the fourth light beam L4 is irradiated to the measurement area M; and, the first light beam L1 is irradiated to the first beam splitter 30 and then partially penetrates to become a fifth light beam L5, and the fifth light beam L5 is irradiated to the Near-infrared light intensity detector 20. Moreover, after the fourth light beam L4 irradiates the measurement area M, it is reflected along the second optical axis A2 to become a sixth light beam L6 (as shown in Figure 3). The sixth light beam L6 passes through the displacement type The focal length meter 40 becomes a seventh light beam L7. The seventh light beam L7 irradiates the second beam splitter 50 and is reflected into an eighth light beam L8. The eighth light beam L8 irradiates the first light beam along the third optical axis A3. The beam splitter 30 passes through the first beam splitter 30 and becomes a ninth light beam L9. The ninth light beam L9 is irradiated to the image detector 70 and becomes a tenth light beam L10.

2. Focus confirmation step S2: Refer to Figure 2. Set a plane reflector 91 in the measurement area M. The plane reflector 91 is vertically oriented toward the second optical axis A2. Control the plane reflector 91 in the measurement area M. On the second optical axis A2, move toward the displacement focus meter 40 (for example, move to a first position P1 or a second position P2), and when moving to a focus position P3, the displacement focus meter 40 is at The plane reflecting mirror 91 has a first focus F1 (as shown in Figure 3). At this time, the fourth light beam L4 is reflected from the plane reflecting mirror 91 and becomes the tenth light beam L10, which is focused on the image detector. Detector 70, thereby achieving a focus confirmer.

3. System calibration step S3: Refer to Figure 4 and prepare a convex optical reflective lens 92. The convex optical reflective lens 92 has a radius of curvature; the radius of curvature is between 7.5mm and 7.8mm; remove the plane Reflector 91, change the convex optical reflective lens 92 to the focus position P3, then the first focus F1 is located on the convex optical lens 92, and first confirm that the tenth light beam L10 is focused on the image detector 70 , then, the convex optical reflective lens 92 is controlled to move toward the displacement focus meter 40 (the tenth light beam L10 will not focus on the image detector 70 at this stage), and when it moves to a test position P4 (the The tenth light beam L10 is focused on the image detector 70 again). At this time, the convex optical lens 92 has a positioning point F2. At this time, the first focus F1 reaches the positioning point F2 (that is, the focus position P3 The first distance R1 from the test position P4 is exactly the radius of curvature of the convex optical reflective lens 92 .

4. Actual measurement step S4: Remove the plane reflector 91 and install a fixed bracket 93 (as shown in Figure 1) in the measurement area M. The fixed bracket 93 is for a person to be measured 94. The head is fixed so that one eye 941 (more specifically, the cornea) of the subject 94 is located at the test position P4 (see Figures 5 and 6) and at the positioning point F2, and the subject is One eye 941 of 94 (the other eye is blocked first) looks at the visible light target 61 . Then the fourth light beam L4 becomes the tenth light beam L10 after being reflected from the eye 941, which is focused to the image detector 70. Then, the relative movement of the displacement focus meter 40 and the eye 941 is fine-tuned (as shown in Figure 6 shown), and when moving a second distance R2 to a focal length position P5 (the displacement focus meter 40 has a second focus F3 on the eye 941), if the fourth light beam L4 is also caused to pass from the eye 941 After reflection, it becomes the tenth When the light beam L10 is focused on the image detector 70, the sum of the first distance R1 and the second distance R2 is the radius of curvature of the eye 941, otherwise it is not, and then ends.

In more detail, referring to Figure 6, it can be imagined that when the second focus F3 is the center, the sum of the first distance R1 and the second distance R2 is the radius of the arc drawn, which can be regarded as a reference. Wavefront; also, the real corneal surface of the eye 941 of the subject 94 can be regarded as a wavefront to be measured; once the reference wavefront matches the wavefront to be measured, the corneal curvature can be confirmed, which is the case in this case The corneal curvature is measured using the principle that the reference wavefront matches the wavefront to be measured.

In practice, the first light beam L1 may be one of a cross mark beam and a rice mark beam.

The wavelength of the first light beam L1 can be between 860nm and 1100nm (preferably), and 980nm is the best.

The near-infrared light intensity detector 20 is used to detect the intensity of the fifth light beam L5 transformed from the first light beam L1, and when the fifth light beam L5 is too strong, it passes through the near-infrared light generator 10 The intensity of the first light beam L1 is weakened to prevent irradiation damage to the eye 941 .

The first beam splitter 30 has a structure that partially reflects and partially transmits near-infrared light.

The second beam splitter 50 has a structure that reflects near-infrared light but transmits visible light.

The image detector 70 may include a near-infrared light filter 71 , a convex lens sheet 72 and a light sensing device 73 .

The near-infrared light filter 71 is used to filter the chaotic light waves of the ninth light beam L9.

The convex lens sheet 72 is used to converge the ninth light beam L9 into the tenth light beam L10. Of course, the convex lens sheet 72 can be one piece or a combination of multiple pieces.

The light sensing device 73 is used to receive the tenth light beam L10.

The light sensing device 73 can be a near-infrared light image capturing device (such as a camera or video camera).

Regarding the actual measurement step S4, when the first light beam L1 is a cross mark beam (as shown in FIG. 7), the tenth light beam L10 is also a cross mark beam.

The radius of curvature of the convex optical reflective lens 92 is preferably 7.7 mm.

Referring to Figures 5 and 6, when the eye 941 of the subject 94 (more specifically, the frontmost end of the cornea or the front apex) is located at the test position P4 and at the positioning point F2, fine-tune The displacement focus meter 40 moves relative to the eye 941, and when moving to the best image of the cross mark beam convergence. Record the position of the displacement focal length meter 40 at this time. The aforementioned position should be moved by the second distance R2 to the focal length position P5, and the curvature of the eye 941 (actually the cornea) of the subject 94 can be calculated. The radius is the sum of the first distance R1 and the second distance R2; and then repeat the above steps to detect the other eye (941) to complete the measurement of the corneal curvature radius of both eyes.

For example, if the first distance R1=7.7mm, and the second distance R2=0.2mm, then the corneal curvature radius of the eye 941 (more specifically, the cornea) of the subject 94 is 7.9mm. .

The advantages and effects of the present invention can be summarized as follows:

[1] It is very convenient to estimate the radius of corneal curvature from the clarity of the beam image. This case mainly sets up the displacement focal length meter and the image detector. When the eye (more specifically, the cornea) of the subject is located at the test position and at the positioning point, the first focus reaches the There is a first distance between the positioning points, which controls the relative movement of the displacement focus meter and the subject's eye (actually the cornea). When moving from the test position to the position where the image detector can detect the cross mark beam (i.e. When the tenth beam) is located in the center and the cross mark beam is symmetrical up, down, left and right, and is the best image of convergence, it should move the second distance and be located at the focal length position, and then the eye of the subject can be deduced ( Actually, the radius of curvature of the cornea is the sum of the first distance and the second distance. Therefore, it is quite convenient to calculate the radius of curvature of the cornea from the clarity of the beam image.

[2] The device is simple, low-cost and easy to operate. The near-infrared light generator, the near-infrared light intensity detector, the first (and second) spectroscope, the displacement focus meter, the visual target generator and the image detector in this case are all publicly known. The device does not need to be developed separately, and the cost is low. The actual operation only requires lighting and observing the clarity of the beam image. Therefore, the device is simple, low-cost and easy to operate.

The above is only a detailed description of the present invention through preferred embodiments. Any simple modifications and changes made to the embodiments do not deviate from the spirit and scope of the present invention.

10: Near infrared light generator

20: Near infrared light intensity detector

30: First beam splitter

40: Displacement focal length meter

50: Second beam splitter

60: Optotype generator

70:Image detector

71: Near infrared light filter

93: Fixed bracket

94:Testee

941:Eye

M: Measurement area

A1: first optical axis

A2: Second optical axis

A3: The third optical axis

Claims (9)

A corneal curvature measurement system includes: a near-infrared light generator, which is used to emit a first light beam along a first optical axis and can adjust the intensity of the first light beam. The first light beam is near Infrared light; a near-infrared light intensity detector, which is provided corresponding to the near-infrared light generator and is located on the first optical axis; a first beam splitter, which is provided between the near-infrared light generator and the near-infrared light generator. between the infrared light intensity detectors and located on the first optical axis; a displacement focus meter is located on a second optical axis, and the second optical axis is parallel to the first optical axis; the displacement focus meter The focal length meter is provided with a measurement area, the measurement area is located on the second optical axis; a second spectroscope is provided on the second optical axis, and the displacement focal length meter is located between the measurement area and the second beam splitter; in addition, the first beam splitter and the second beam splitter are located on a third optical axis, the third optical axis is perpendicular to the first optical axis, and the The third optical axis is perpendicular to the second optical axis; a visual target generator is disposed on a second optical axis; the second spectroscope is between the displacement focal length meter and the visual target generator between; the visual target generator is used to emit a visible light visual target toward the second spectroscope, and the visible light visual target can penetrate the second spectroscope and the displacement focus meter and illuminate the measurement area; and an image detector, which is provided corresponding to the first beam splitter and is located on the third optical axis. The first beam splitter is between the second beam splitter and the image detector; whereby , the first beam irradiates the first beam splitter and is partially reflected and partially penetrates; after partial reflection, it becomes a second beam, and the second beam irradiates the second beam splitter along the third optical axis and is reflected Becoming a third light beam, the third light beam passes through the displacement focus meter along the second optical axis and becomes a fourth light beam. The fourth beam is irradiated to the measurement area; and the first beam is irradiated to the first beam splitter and partially penetrates into a fifth beam, and the fifth beam is irradiated to the near-infrared light intensity detector. The detector; and, after the fourth light beam irradiates the measurement area, it is reflected along the second optical axis to become a sixth light beam, and the sixth light beam passes through the displacement focus meter and becomes a seventh light beam. Seven light beams are irradiated to the second beam splitter and reflected into an eighth beam. The eighth beam is irradiated to the first beam splitter along the third optical axis and penetrates the first beam splitter to become a ninth beam. The ninth light beam is irradiated to the image detector and becomes a tenth light beam. The corneal curvature measurement system of claim 1, wherein the first light beam is one of a cross mark beam and a rice mark beam. The corneal curvature measurement system of claim 2, wherein the wavelength of the first light beam is between 860nm and 1100nm. The corneal curvature measurement system as described in claim 1, wherein the image detector includes: a near-infrared light filter used to filter the light waves of the ninth beam; a convex lens lens used to make the The ninth light beam converges into the tenth light beam; and a light sensing device is used to receive the tenth light beam. A method for measuring corneal curvature includes the following steps: 1. Preparation step: prepare a near-infrared light generator, a near-infrared light intensity detector, a first spectroscope, a displacement focus meter, and a second A spectroscope, an optical target generator and an image detector; the near-infrared light generator is used to emit a first light beam along a first optical axis and can adjust the intensity of the first light beam. is near-infrared light; the near-infrared light intensity detector is generated corresponding to the near-infrared light The first beam splitter is provided between the near-infrared light generator and the near-infrared light intensity detector and is located on the first optical axis; the displacement The type focus meter is set on a second optical axis, and the second optical axis is parallel to the first optical axis; the displacement focus meter is set up with a measurement area, and the measurement area is located on the second optical axis. ; The second beam splitter is located on the second optical axis, and the displacement focus meter is between the measurement area and the second beam splitter; and, the first beam splitter and the second beam splitter are located on a third optical axis, the third optical axis is perpendicular to the first optical axis, and the third optical axis is perpendicular to the second optical axis; the visual mark generator is configured On a second optical axis, the second spectroscope is between the displacement focus meter and the visual target generator; the visual target generator is used to emit a visible light visual target toward the second spectroscope, The visible light sight mark can penetrate the second spectroscope and the displacement focus meter and illuminate the measurement area; the image detector is provided corresponding to the first spectroscope and is located on the third optical axis , the first beam splitter is between the second beam splitter and the image detector; whereby, after the first beam irradiates the first beam splitter, it is partially reflected and partially penetrated; after partial reflection, it becomes A second light beam, the second light beam is irradiated to the second spectroscope along the third optical axis and reflected into a third light beam, and the third light beam passes through the displacement focus meter along the second optical axis to become A fourth light beam, the fourth light beam is irradiated to the measurement area; and, the first light beam is irradiated to the first beam splitter and partially penetrates into a fifth light beam, the fifth light beam is irradiated to the near-infrared a light intensity detector; and, after the fourth light beam irradiates the measurement area, it is reflected along the second optical axis to become a sixth light beam, and the sixth light beam passes through the displacement focus meter and becomes a seventh light beam. , the seventh beam irradiates the second beam splitter and is reflected into an eighth beam. The eighth beam irradiates the first beam splitter along the third optical axis, and penetrates the first beam splitter to become a first beam splitter. Nine beams, the ninth beam is irradiated to the image detector and becomes a tenth beam; 2. Focus confirmation step: Set a plane reflector in the measurement area, and the plane reflector is vertically facing the second The optical axis controls the plane mirror to move toward the displacement focal length meter on the second optical axis, and when moving to a focusing position, the displacement focal length meter has a first position on the plane mirror. Focus, at this time, the fourth light beam becomes the tenth light beam after being reflected from the plane mirror, and is focused on the image detector to achieve focus confirmation; 3. System calibration steps: prepare a convex optical reflection lens, The convex optical reflective lens has a radius of curvature; the curvature radius is between 7.5mm and 7.8mm; remove the plane reflector and set the convex optical reflective lens at the focusing position, then the first focus It is located on the convex optical lens, and first confirms that the tenth light beam is focused on the image detector, and then controls the convex optical reflective lens to move towards the displacement focus meter, and when it moves to a test position, at this time , the convex optical lens has a certain positioning point, then the first distance from the first focus to the positioning point is exactly the radius of curvature of the convex optical reflecting lens; and 4. Actual measurement steps: remove the plane reflection The mirror is replaced with a fixed bracket in the measurement area. The fixed bracket is used to fix the head of a person being measured so that one eye of the person being measured is located at the test position and at the positioning point, and Make one eye of the subject look at the visible light target; then the fourth light beam becomes the tenth light beam after being reflected from the eye, and is focused on the image detector. Then, fine-tune the displacement focus meter and the eye. Relative movement, and when moving a second distance to a focal length position, if the fourth light beam is also reflected from the eye and becomes the tenth light beam, focused on the image detector, then the first distance and the The sum of the second distance is the radius of curvature of the eye, and vice versa. The method for measuring corneal curvature as described in claim 5, wherein the first light beam is one of a cross mark beam and a rice mark beam. The method for measuring corneal curvature as described in claim 6, wherein the wavelength of the first light beam is between 860nm and 1100nm. The method for measuring corneal curvature as described in claim 5, wherein the image detector includes: A near-infrared light filter is used to filter the light waves of the ninth light beam; a convex lens sheet is used to converge the ninth light beam into the tenth light beam; and a light sensing device is used to receive the tenth light beam. . The method for measuring corneal curvature as described in claim 5, wherein the radius of curvature of the convex optical reflective lens is 7.7 mm.

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