CN210931345U

CN210931345U - Refractometer

Info

Publication number: CN210931345U
Application number: CN201921719882.1U
Authority: CN
Inventors: 陈华
Original assignee: Zhejiang Weizhen Medical Technology Co ltd
Current assignee: Zhejiang Weizhen Medical Technology Co ltd
Priority date: 2019-10-14
Filing date: 2019-10-14
Publication date: 2020-07-07
Anticipated expiration: 2029-10-14

Abstract

The utility model belongs to the technical field of optometry instruments, in particular to an optometry instrument, which comprises a shell, wherein a projection light path, a measurement light path, a fixation light path and a measured eye positioning and monitoring light path are arranged in the shell, and the measurement light path comprises a rotating prism, a third reflector, a third lens, a fourth optical lens cone, a fourth reflector, a third spectroscope and a CCD image sensor; the measured eye positioning monitoring optical path comprises a fourth lens, a shading device, a fifth optical lens barrel, a sixth optical lens barrel and a CCD image sensor, and the shading device can shade or conduct light irradiation of the measured eye positioning monitoring optical path; the utility model has the advantages that the measuring light path and the measured eye positioning and monitoring light path share the same CCD image sensor, thereby effectively reducing the manufacturing cost, reducing the circuit connection in the optometry instrument and improving the production efficiency; when the degree of myopia or hypermetropia of the tested eye is measured, the light irradiation of the positioning monitoring light path of the tested eye is shielded through the shading device, and the measuring accuracy is ensured.

Description

Refractometer

The technical field is as follows:

the utility model belongs to the technical field of optometry appearance, refer in particular to an optometry appearance.

Background art:

the present computerized optometry instruments use an objective measurement mode, which projects an infrared image to the eye fundus of a person, generates a scattering image on the retina of the person, and objectively calculates the diopter of the eye by analyzing a measurement image acquired by a CCD.

The optical system of a full-automatic optometry instrument and the automatic detection and positioning method thereof disclosed in the prior Chinese invention patent (publication No. CN106419829B) comprise a projection light path, a measurement light path, a fixation system and a measured eye positioning and monitoring system, wherein the projection light path sequentially comprises an infrared light source, a first optical lens barrel, a first lens, a first reflector, a first spectroscope and a second spectroscope, the measurement light path sequentially comprises a rotating prism, a second reflector, a second lens, a second optical lens barrel and a first CCD image sensor, the fixation system sequentially comprises a visible light source, a third optical lens barrel, a fourth optical lens barrel, a third lens and a third reflector, the measured eye positioning and monitoring system sequentially comprises a fourth lens, a fifth optical lens barrel, a sixth optical lens barrel and a second CCD image sensor, a light source emitted by the infrared light source is reflected by a measured eye to form an image on the first CCD image sensor, infrared light having a wavelength different from that of the infrared light source, and cone-shaped light beams emitted from the green and blue light sources are imaged on the second CCD image sensor.

The first CCD image sensor and the second CCD image sensor have the same function, and are mainly different in that the first CCD image sensor and the second CCD image sensor receive images of different light sources, and the CCD image sensor is high in cost and complex in circuit electrically connected with a control assembly of the optometry instrument, so that the structural design causes high manufacturing cost and low production efficiency of the whole optometry instrument.

The invention content is as follows:

the utility model aims at providing a measure the same CCD image sensor of light path and surveyed eye location surveillance light path sharing, the lower refractometer of cost.

The utility model discloses a realize like this:

an optometry instrument comprises a shell, wherein a projection light path, a measurement light path, a fixation light path and a measured eye positioning and monitoring light path are arranged in the shell, and the projection light path sequentially comprises an infrared light source, a first optical lens barrel, a first lens, a first reflector, a first spectroscope and a second spectroscope along a light irradiation direction; the fixed vision light path sequentially comprises a visible light source, a second optical lens barrel, a third optical lens barrel, a second lens and a second reflector along the light irradiation direction;

the measuring optical path sequentially comprises a rotating prism, a third reflector, a third lens, a fourth optical lens barrel, a fourth reflector, a third beam splitter and a CCD image sensor along the light irradiation direction;

the eye positioning and monitoring optical path to be detected sequentially comprises a fourth lens, a shading device, a fifth optical lens barrel, a sixth optical lens barrel and a CCD image sensor along the light irradiation direction, and the shading device can shade or conduct the light irradiation of the eye positioning and monitoring optical path to be detected;

the CCD image sensor in the measuring optical path is the same as the CCD image sensor in the measured eye positioning monitoring optical path; the first reflecting mirror, the rotating prism and the first spectroscope are positioned on the same light path, the second reflecting mirror, the first spectroscope and the second spectroscope are positioned on the same light path, the second spectroscope, the fourth lens and the fifth optical lens barrel are positioned on the same light path, the fifth optical lens barrel, the third spectroscope and the sixth optical lens barrel are positioned on the same light path, and the second spectroscope and the pupil of the eye to be detected are positioned on the same light path through the ocular objective lens.

In the above-mentioned optometry appearance, shade including fix the driving source in the casing, the flexible end of driving source is connected with the one end of light screen, and the other end of light screen is the free end, and when the flexible end of driving source stretches out or contracts, the free end of light screen can shelter from the light irradiation of being surveyed eye location monitoring light path.

In foretell optometry appearance, the driving source is the electro-magnet, the middle part of light screen is passed through the pivot and is rotated the connection on the casing, and the one end that the light screen is close to the electro-magnet is seted up and is seted up along its axial and seted up bar hole or open slot, the flexible end of electro-magnet and the one end fixed connection of horizontal pole, and the other end of horizontal pole is located bar hole or open slot, and the axis of horizontal pole is mutually perpendicular with the flexible end axis of electro-magnet, is located to overlap on the electro-magnet telescopic link between the casing of horizontal pole and.

In the above refractometer, the light shielding device switches between shielding and conducting of light irradiation to the eye positioning monitoring optical path at intervals of 0.5s-2 s.

In the above refractometer, the first optical lens barrel, the second optical lens barrel and the fourth optical lens are all arranged along the left and right horizontal directions, a slide rail is arranged in the shell along the left and right horizontal directions, a slide block mounting seat is connected to the slide rail in a sliding manner, the first optical lens barrel, the second optical lens barrel and the fourth optical lens are fixed on the slide block mounting seat, a power source is arranged on the shell, and the slide block mounting seat is driven by the power source to drive the first optical lens barrel, the second optical lens barrel and the fourth optical lens to move left and right along the slide rail.

In foretell optometry appearance, the power supply is driving motor, is fixed with the rope guide wheel on driving motor's the output shaft, is located to rotate respectively on the casing of slide rail left and right sides and is connected with left from the driving wheel and right from the driving wheel, and the winding has the rope on the rope guide wheel, and the one end of rope is through setting up in the left side of slider mount pad from the driving wheel and with slider mount pad left end fixed connection, the other end through set up in the right side on slider mount pad right side from the driving wheel and with the right-hand member fixed connection of slider.

In the above refractometer, a tension wheel for adjusting the tightness of the rope is arranged on the housing.

In the above optometry instrument, a positioning infrared lamp and a positioning plate are arranged between the ocular objective and the eye to be measured, a central hole is formed in the center of the positioning plate, the positioning infrared lamp can emit infrared light with a wavelength different from that of infrared light of an infrared light source, and the infrared light irradiates the cornea of the eye to be measured through the positioning plate.

In the above refractometer, the first spectroscope, the second spectroscope and the third spectroscope are all manufactured by a multilayer film vacuum method, and the transmission and reflection ratio of the first spectroscope, the second spectroscope and the third spectroscope is 1: 1.

In the above refractometer, the measured eye positioning and monitoring optical path further includes a first filter and a second filter for eliminating stray light, the first filter is located on the optical path between the second spectroscope and the fourth lens, and the second filter is located on the optical path between the fourth lens and the light shielding device or between the light shielding device and the fifth optical lens barrel.

Compared with the prior art, the utility model outstanding advantage is:

1. the utility model has the advantages that the measuring light path and the measured eye positioning and monitoring light path share the same CCD image sensor, thereby effectively reducing the manufacturing cost, reducing the circuit connection in the optometry instrument and improving the production efficiency;

2. when the utility model is used for measuring the degree of myopia or hyperopia of the measured eye, in order to avoid the influence of the light interference of the measured eye positioning monitoring light path on the measurement result, the light irradiation of the measured eye positioning monitoring light path is shielded by the shading device, so that the CCD image sensor can only receive the ring image from the measuring light path, thereby ensuring the measurement accuracy; when the measured eye is accurately positioned and the measurement error is reduced, the image formed by the measured eye positioning monitoring light path is only concentric with the preset point-shaped circle, and the light of the measurement light path has no influence on the image, so that the light irradiation of the measured eye positioning monitoring light path is conducted through the shading device.

Description of the drawings:

fig. 1 is a schematic diagram of the optical path of the present invention;

FIG. 2 is a first perspective view of the present invention;

fig. 3 is a perspective view of the light shielding device of the present invention;

FIG. 4 is a second overall perspective view of the present invention;

fig. 5 is a third overall perspective view of the present invention.

In the figure: 101. an infrared light source; 102. a first optical barrel; 103. a first lens; 104. a first reflective mirror; 105. a first beam splitter; 106. a second spectroscope; 201. a visible light source; 202. a second optical barrel; 203. a third optical barrel; 204. a second lens; 205. a second reflective mirror; 301. rotating the prism; 302. a third reflective mirror; 303. a third lens; 304. a fourth optical barrel; 305. a fourth reflective mirror; 306. a third beam splitter; 401. a fourth lens; 402. a fifth optical barrel; 403. a sixth optical barrel; 404. a first filter; 405. a second filter; 411. a light shielding device; 412. an electromagnet; 413. A visor; 414. an open slot; 415. a cross bar; 500. a CCD image sensor; 601. the eye to be tested; 602. An ocular objective lens; 603. positioning an infrared lamp; 604. positioning a plate; 605. a central bore; 700. a housing; 801. A slide rail; 802. a slider mounting base; 803. a drive motor; 804. a rope guide pulley; 805. a left driven wheel; 806. A right driven wheel; 807. a rope; 808. a tension wheel.

The specific implementation mode is as follows:

the invention will now be further described with reference to specific embodiments, with reference to figures 1 to 5:

an optometry instrument comprises a shell 700, wherein a projection light path, a measurement light path, a fixation light path and a measured eye positioning monitoring light path are arranged in the shell 700, and the projection light path sequentially comprises an infrared light source 101, a first optical lens barrel 102, a first lens 103, a first reflector 104, a first spectroscope 105 and a second spectroscope 106 along a light irradiation direction; the fixed vision optical path comprises a visible light source 201, a second optical lens barrel 202, a third optical lens barrel 203, a second lens 204 and a second reflector 205 in sequence along the light irradiation direction;

the measuring optical path comprises a rotating prism 301, a third reflector 302, a third lens 303, a fourth optical lens barrel 304, a fourth reflector 305, a third beam splitter 306 and a CCD image sensor 500 in sequence along the light irradiation direction;

the eye positioning and monitoring optical path to be detected sequentially comprises a fourth lens 401, a light shielding device 411, a fifth optical lens barrel 402, a sixth optical lens barrel 403 and a CCD image sensor 500 along the light irradiation direction, and the light shielding device 411 can shield or conduct the light irradiation of the eye positioning and monitoring optical path to be detected;

the CCD image sensor 500 in the measuring optical path is the same as the CCD image sensor 500 in the measured eye positioning monitoring optical path; the first reflecting mirror 104, the rotating prism 301 and the first beam splitter 105 are located on the same optical path, the second reflecting mirror 205, the first beam splitter 105 and the second beam splitter 106 are located on the same optical path, the second beam splitter 106, the fourth lens 401 and the fifth optical lens barrel 402 are located on the same optical path, the fifth optical lens barrel 402, the third beam splitter 306 and the sixth optical lens barrel 403 are located on the same optical path, and the second beam splitter 106 and the pupil of the eye 601 to be detected are located on the same optical path through the objective lens 602.

Furthermore, a positioning infrared lamp 603 and a positioning plate 604 are disposed between the ocular objective 602 and the eye 601, a center hole 605 is disposed at the center of the positioning plate 604, the positioning infrared lamp 603 can emit infrared light with a wavelength different from that of the infrared light from the infrared light source 101, and the infrared light irradiates the cornea of the eye 601 through the positioning plate 604. The central hole 605 is a light path between the pupil of the measured eye 601 and the corresponding light path.

The utility model discloses a theory of operation:

firstly, an infrared light source 101 emits a light source which passes through a first optical lens barrel 102 to form an annular target, and the light source is emitted in parallel through a first lens 103, reflected by a first reflecting mirror 104, a first beam splitter 105 and a second beam splitter 106, and finally enters the pupil of a tested eye 601 through a central hole 605 of an eye objective lens 602 and a positioning plate 604;

secondly, the light reflected from the pupil of the eye 601 to be measured is emitted in parallel through the center hole 605 of the positioning plate 604 and the ocular objective 602, reflected by the second beam splitter 106 and the first beam splitter 105, passes through the rotating prism 301 and the small hole on the first reflective mirror 104 to reach the third reflective mirror 302, is reflected by the third reflective mirror 302, then passes through the third lens 303 and the fourth optical lens barrel 304 in sequence, is reflected by the fourth reflective mirror 305 and the third beam splitter 306, and finally forms an image on the CCD image sensor 500 through the sixth optical lens barrel 403;

thirdly, the visible light source 201 passes through the second optical lens barrel 202 and the third optical lens barrel 203, is incident on the second reflective mirror 205 in parallel through the second lens 204, is reflected by the second reflective mirror 205, is reflected by the first beam splitter 105 at the second beam splitter 106, and finally enters the pupil of the eye 601 to be measured through the objective lens 602 and the central hole 605 of the positioning plate 604;

fourthly, the positioning infrared lamp 603 emits infrared light with a wavelength different from that of the infrared light source 101, the infrared light irradiates the cornea of the eye 601 to be measured through the positioning plate 604, the infrared light is reflected from the cornea of the eye 601 to be measured through the center hole 605 of the positioning plate 604, the ocular objective lens 602, the second spectroscope 106, the fourth lens 401, the fifth optical lens barrel 402, the third spectroscope 306 and the sixth optical lens barrel 403, and finally the image is formed on the CCD image sensor 500 and is concentric with the preset point circle.

Wherein, the measuring optical path is used for measuring the degree of myopia or hyperopia of the tested eye 601; the vision fixation optical path is used for measuring the aging degree of the tested eye 601; the measured eye positioning monitoring optical path is used for accurately positioning the measured eye 601 and reducing measurement errors.

Therefore, when measuring the degree of myopia or hypermetropia of the measured eye 601, in order to avoid the light interference of the measured eye positioning monitoring optical path from affecting the measurement result, the utility model shields the light irradiation of the measured eye positioning monitoring optical path by means of the shading device 411, so that the CCD image sensor 500 can only receive the ring image from the measuring optical path, thereby ensuring the measurement accuracy; when the eye 601 is accurately positioned and the measurement error is reduced, the image formed by the eye positioning and monitoring optical path is concentric with the preset point-like circle, but the light of the measurement optical path has no influence on the image, so that the light irradiation of the eye positioning and monitoring optical path is conducted through the shading device 411.

Further, the embodiment of the shade 411: the light shielding device 411 includes a driving source fixed in the housing 700, a telescopic end of the driving source is connected to one end of the light shielding plate 413, the other end of the light shielding plate 413 is a free end, and when the telescopic end of the driving source extends or retracts, the free end of the light shielding plate 413 can shield the light irradiation of the eye to be detected positioning monitoring light path.

The driving source may be a driving cylinder, and the shielding of the free end of the light shielding plate 413 against the light irradiation of the positioning monitoring light path for shielding the eye to be detected is realized through the telescopic motion of the driving cylinder.

In this embodiment, the driving source is an electromagnet 412, the middle of the light shielding plate 413 is rotatably connected to the housing 700 through a shaft pin, one end of the light shielding plate 413 close to the electromagnet 412 is provided with a strip-shaped hole or an open slot 414 along the axial direction of the electromagnet, the telescopic end of the electromagnet 412 is fixedly connected with one end of the cross bar 415, the other end of the cross bar 415 is located in the strip-shaped hole or the open slot 414, the axis of the cross bar 415 is perpendicular to the axis of the telescopic end of the electromagnet 412, and a return spring is sleeved on the telescopic rod of the electromagnet 412 located between the cross bar 415 and the housing. When the electromagnet 412 is powered on, the telescopic rod of the electromagnet 412 is contracted to drive the light shielding plate 413 to rotate through the cross rod 415, so that the free end of the light shielding plate 413 is far away from the light irradiation of the measured eye positioning monitoring light path; when the electromagnet 412 is powered off, the telescopic rod of the electromagnet 412 extends outwards to reset under the elastic force of the reset spring, and the cross rod 415 drives the light shielding plate 413 to rotate, so that the free end of the light shielding plate 413 shields the light irradiation of the measured eye positioning monitoring light path.

Furthermore, in order to ensure the accurate positioning of the measured eye 601 during the measurement process and reduce the measurement error, the light shielding device 411 switches the shielding and conducting of the light irradiation of the measured eye positioning monitoring optical path at certain intervals, and the interval is 0.5s-2s, while in the present embodiment, the interval is 0.5 s.

Furthermore, the first optical lens barrel 102, the second optical lens barrel 202 and the fourth optical lens are all arranged along the left-right horizontal direction, a slide rail 801 is arranged in the housing 700 along the left-right horizontal direction, a slide block mounting seat 802 is connected to the slide rail 801 in a sliding manner, the first optical lens barrel 102, the second optical lens barrel 202 and the fourth optical lens are fixed to the slide block mounting seat 802, a power source is arranged on the housing 700, and the slide block mounting seat 802 is driven by the power source to drive the first optical lens barrel 102, the second optical lens barrel 202 and the fourth optical lens to move left and right along the slide rail 801. When the measuring optical path measures the near-sighted or far-sighted power of the eye 601 to be measured and the fixed vision optical path measures the presbyopia power of the eye 601 to be measured, the slider mounting seat 802 is driven by the power source to adjust the left and right positions of the first optical lens barrel 102, the second optical lens barrel 202 and the fourth optical lens, and the near-sighted or far-sighted power and the presbyopia power of the eye 601 to be measured can be obtained by the displacement of the first optical lens barrel 102, the second optical lens barrel 202 and the fourth optical lens.

In this embodiment, the specific structure of the connection relationship between the power source and the slider mounting seat 802 is as follows: the power source is a driving motor 803, a rope guide pulley 804 is fixed on an output shaft of the driving motor 803, a left driven pulley 805 and a right driven pulley 806 are respectively rotatably connected to the shells 700 at the left and right sides of the sliding rail 801, a rope 807 is wound on the rope guide pulley 804, one end of the rope 807 passes through the left driven pulley 805 arranged at the left side of the slider mounting seat 802 and is fixedly connected with the left end of the slider mounting seat 802, and the other end of the rope 807 passes through the right driven pulley 806 arranged at the right side of the slider mounting seat 802 and is fixedly connected with the right end of the slider.

Further, a tension pulley 808 for adjusting the tightness of the rope 807 is provided on the housing 700.

Furthermore, the first spectroscope 105, the second spectroscope 106 and the third spectroscope 306 are all manufactured by a multilayer film vacuum method, and the transmission and reflection ratio of the first spectroscope 105, the second spectroscope 106 and the third spectroscope 306 is 1: 1.

Meanwhile, in order to avoid the light emitted by the visible light source 201 from being directly refracted to enter the measured eye positioning monitoring optical path, the measured eye positioning monitoring optical path further includes a first filter 404 and a second filter 405 for eliminating stray light, the first filter is located on the optical path between the second beam splitter 106 and the fourth lens 401, and the second filter is located on the optical path between the fourth lens 401 and the light shielding device 411 or between the light shielding device 411 and the fifth optical lens barrel 402. In the present embodiment, the second filter mirror is located on the optical path between the light shielding device 411 and the fifth optical barrel 402.

The above-mentioned embodiment is only one of the preferred embodiments of the present invention, and the scope of the present invention is not limited thereto, so: all equivalent changes made according to the shape, structure and principle of the utility model are covered within the protection scope of the utility model.

Claims

1. An optometry instrument comprises a shell, wherein a projection light path, a measurement light path, a fixation light path and a measured eye positioning and monitoring light path are arranged in the shell, and the projection light path sequentially comprises an infrared light source (101), a first optical lens barrel (102), a first lens (103), a first reflector (104), a first spectroscope (105) and a second spectroscope (106) along a light irradiation direction; the fixation light path comprises a visible light source (201), a second optical lens barrel (202), a third optical lens barrel (203), a second lens (204) and a second reflector (205) in sequence along the light irradiation direction, and is characterized in that:

the measuring optical path sequentially comprises a rotary prism (301), a third reflector (302), a third lens (303), a fourth optical lens barrel (304), a fourth reflector (305), a third spectroscope (306) and a CCD image sensor along the light irradiation direction;

the eye positioning monitoring optical path to be detected sequentially comprises a fourth lens (401), a shading device, a fifth optical lens barrel (402), a sixth optical lens barrel (403) and a CCD image sensor (500) along the light irradiation direction, and the shading device can shade or conduct the light irradiation of the eye positioning monitoring optical path to be detected;

the CCD image sensor (500) in the measuring optical path is the same as the CCD image sensor (500) in the measured eye positioning monitoring optical path; the first reflecting mirror (104), the rotating prism (301) and the first spectroscope (105) are located on the same light path, the second reflecting mirror (205), the first spectroscope (105) and the second spectroscope (106) are located on the same light path, the second spectroscope (106), the fourth lens (401) and the fifth optical lens barrel (402) are located on the same light path, the fifth optical lens barrel (402), the third spectroscope (306) and the sixth optical lens barrel (403) are located on the same light path, and the second spectroscope (106) is located on the same light path through the objective lens (602) and the pupil of the eye to be measured (601).

2. An optometry instrument according to claim 1, wherein: the shading device (411) comprises a driving source fixed in the shell (700), the telescopic end of the driving source is connected with one end of the shading plate (413), the other end of the shading plate (413) is a free end, and when the telescopic end of the driving source extends or retracts, the free end of the shading plate (413) can shield the light irradiation of the measured eye positioning monitoring light path.

3. An optometry instrument according to claim 2, wherein: the driving source is an electromagnet (412), the middle of the shading plate (413) is rotatably connected to the shell (700) through a shaft pin, one end, close to the electromagnet (412), of the shading plate (413) is provided with a strip-shaped hole or an open slot (414) along the axial direction of the shading plate, the telescopic end of the electromagnet (412) is fixedly connected with one end of the cross rod (415), the other end of the cross rod (415) is located in the strip-shaped hole or the open slot (414), the axis of the cross rod (415) is perpendicular to the axis of the telescopic end of the electromagnet (412), and a reset spring is sleeved on the telescopic rod of the electromagnet (412) located between the shell (700) of the cross rod (415) and the.

4. An optometric instrument according to claim 1, 2 or 3, wherein: the shading device (411) switches shading and conducting of light irradiation of the measured eye positioning monitoring light path at certain intervals, and the interval time is 0.5s-2 s.

5. An optometry instrument according to claim 1, wherein: the first optical lens barrel (102), the second optical lens barrel (202) and the fourth optical lens are arranged in the left-right horizontal direction, a sliding rail (801) is arranged in the shell (700) in the left-right horizontal direction, a sliding block mounting seat (802) is connected onto the sliding rail (801) in a sliding mode, the first optical lens barrel (102), the second optical lens barrel (202) and the fourth optical lens are fixed onto the sliding block mounting seat (802), a power source is arranged on the shell (700), and the sliding block mounting seat (802) is driven by the power source to drive the first optical lens barrel (102), the second optical lens barrel (202) and the fourth optical lens to move left and right along the sliding rail (801).

6. An optometry instrument according to claim 5, wherein: the power supply is driving motor (803), be fixed with on the output shaft of driving motor (803) and lead rope sheave (804), be located on casing (700) of slide rail (801) left and right sides and rotate respectively and be connected with left from driving wheel (805) and right from driving wheel (806), it has rope (807) to twine on leading rope sheave (804), the one end of rope (807) is through setting up in left from driving wheel (805) on slider mount pad (802) left side and with slider mount pad (802) left end fixed connection, the other end is through setting up in right from driving wheel (806) on slider mount pad (802) right side and with the right-hand member fixed connection of slider mount pad (802).

7. An optometry instrument according to claim 6, wherein: and a tension wheel (808) for adjusting the tightness of the rope (807) is arranged on the shell (700).

8. An optometry instrument according to claim 1, wherein: a positioning infrared lamp (603) and a positioning plate (604) are arranged between the ocular objective lens (602) and the eye to be measured (601), a central hole (605) is formed in the center of the positioning plate (604), the positioning infrared lamp (603) can emit infrared light with a wavelength different from that of infrared light of an infrared light source, and the infrared light irradiates the cornea of the eye to be measured (601) through the positioning plate (604).

9. An optometry instrument according to claim 1, wherein: the first spectroscope (105), the second spectroscope (106) and the third spectroscope (306) are all manufactured by a multilayer film vacuum method, and the transmission and reflection ratio of the first spectroscope (105), the second spectroscope (106) and the third spectroscope (306) is 1: 1.

10. An optometry instrument according to claim 1, wherein: the measured eye positioning and monitoring optical path further comprises a first filter (404) and a second filter (405) for eliminating stray light, the first filter is located on the optical path between the second beam splitter (106) and the fourth lens (401), and the second filter is located on the optical path between the fourth lens (401) and the shading device (411) or between the shading device (411) and the fifth optical lens barrel (402).