Search

CN-116195966-B - Vision detection method and system based on space arbitrary position

CN116195966BCN 116195966 BCN116195966 BCN 116195966BCN-116195966-B

Abstract

The invention discloses a vision detection method and a vision detection system based on any space position, wherein the method comprises the steps of obtaining a geometric center of a visual target, constructing a three-dimensional coordinate system by taking the geometric center as an origin, obtaining position information of eyes of a tested person in the three-dimensional coordinate system, determining a horizontal visual angle of the tested person compared with the minimum horizontal visual target and a vertical visual angle compared with the minimum vertical visual target according to the minimum horizontal visual target, the minimum vertical visual target and the position information which can be resolved by the tested person, and determining a standard vision value of the tested person according to the horizontal visual angle and the vertical visual angle. The method and the system can realize vision detection of any position in space, one person or a plurality of persons at the same time, have high detection efficiency and detection accuracy, are higher than the 0.1-degree visual angle (5-minute recording method) of the national standard, and have wide application scenes and strong practicability.

Inventors

  • ZHANG YUN
  • HAO JI
  • HE ZHENBING

Assignees

  • 北京国科启明教育科技有限公司

Dates

Publication Date
20260505
Application Date
20221230

Claims (8)

  1. 1.A vision testing method based on any spatial position, comprising: Obtaining a geometric center of a visual target, and constructing a three-dimensional coordinate system by taking the geometric center as an origin; acquiring position information of eyes of a tested person in the three-dimensional coordinate system; Determining a horizontal visual angle of the tested person compared with the minimum horizontal visual target and a vertical visual angle of the tested person compared with the minimum vertical visual target according to the minimum horizontal visual target, the minimum vertical visual target and the position information which can be distinguished by the tested person, wherein the horizontal visual target is a visual target with an opening facing left or right, and the vertical visual target is a visual target with an opening facing up or down; Determining a standard vision value of the tested person according to the horizontal visual angle and the vertical visual angle; the method for determining the horizontal visual angle of the tested person compared with the minimum horizontal visual target and the vertical visual angle compared with the minimum vertical visual target specifically comprises the following steps: acquiring a first length between the middle points of the left side and the right side of the minimum horizontal visual target, and determining a horizontal visual angle of the tested person compared with the minimum horizontal visual target according to the first length and the position information; And acquiring a second length between the middle points of the upper side and the lower side of the minimum vertical visual target, and determining the vertical visual angle of the tested person compared with the minimum vertical visual target according to the second length and the position information.
  2. 2. The method for spatially arbitrary position-based vision testing according to claim 1, wherein determining the horizontal viewing angle of the subject as compared to the minimum horizontal optotype comprises: determining a horizontal viewing angle of the subject compared to the minimum horizontal optotype according to a first formula: ; wherein: For a horizontal viewing angle, For a first length between the midpoints of the left and right sides of the minimum horizontal optotype, In the three-dimensional coordinate system for the tested person The axis of the rotation is set to be at the same position, In the three-dimensional coordinate system for the tested person The axis of the rotation is set to be at the same position, In the three-dimensional coordinate system for the tested person And (5) axis coordinates.
  3. 3. The method for spatially arbitrary position based vision testing according to claim 1, wherein determining the vertical viewing angle of the subject as compared to the minimum vertical optotype comprises: determining a vertical viewing angle of the subject compared to the minimum vertical optotype according to a second formula: ; In the formula, For a vertical viewing angle of view, For a first length between the midpoints of the upper and lower sides of the minimum vertical optotype, In the three-dimensional coordinate system for the tested person The axis of the rotation is set to be at the same position, In the three-dimensional coordinate system for the tested person The axis of the rotation is set to be at the same position, In the three-dimensional coordinate system for the tested person And (5) axis coordinates.
  4. 4. A method of spatially arbitrary position based vision testing according to any one of claims 1-3, characterized in that determining the standard vision value of the subject from the horizontal and vertical viewing angles comprises: determining the standard vision value of the tested person according to a third formula, wherein the third formula is as follows: ; In the formula, Is a standard vision value, which is a logarithmic vision value, , For a horizontal viewing angle, Is a vertical viewing angle.
  5. 5. A method of spatially arbitrary position based vision testing according to any one of claims 1-3, characterized in that determining the standard vision value of the subject from the horizontal and vertical viewing angles comprises: comparing the horizontal viewing angle with the vertical viewing angle; When the horizontal visual angle is smaller than the vertical visual angle, determining a standard vision value of the tested person by using the horizontal visual angle corresponding to the minimum horizontal visual target; And when the vertical visual angle is smaller than or equal to the horizontal visual angle, determining the standard vision value of the tested person by using the vertical visual angle corresponding to the minimum vertical visual target.
  6. 6. The spatially arbitrary position based vision testing method of claim 1, wherein the subject is one or more.
  7. 7. The spatially arbitrary position based vision testing method of claim 1, wherein the horizontal viewing angle is less than ±60° and the vertical viewing angle is less than ±30°.
  8. 8. A vision testing system based on spatially arbitrary locations, comprising: The coordinate construction module is used for acquiring the geometric center of the standard visual target and constructing a three-dimensional coordinate system by taking the geometric center as an origin; the position determining module is used for acquiring the position information of the eyes of the tested person in the three-dimensional coordinate system; The visual angle determining module is used for determining a horizontal visual angle of the testee compared with the minimum horizontal visual target and a vertical visual angle of the testee compared with the minimum vertical visual target according to the minimum horizontal visual target, the minimum vertical visual target and the position information which can be distinguished by the testee, wherein the horizontal visual target is a visual target with an opening facing left or right, and the vertical visual target is a visual target with an opening facing up or down; The vision determining module is used for determining a standard vision value of the tested person according to the horizontal visual angle and the vertical visual angle; the method for determining the horizontal visual angle of the tested person compared with the minimum horizontal visual target and the vertical visual angle compared with the minimum vertical visual target specifically comprises the following steps: acquiring a first length between the middle points of the left side and the right side of the minimum horizontal visual target, and determining a horizontal visual angle of the tested person compared with the minimum horizontal visual target according to the first length and the position information; And acquiring a second length between the middle points of the upper side and the lower side of the minimum vertical visual target, and determining the vertical visual angle of the tested person compared with the minimum vertical visual target according to the second length and the position information.

Description

Vision detection method and system based on space arbitrary position Technical Field The invention discloses a vision detection method and system based on any spatial position, and belongs to the technical field of vision detection. Background The national normal vision standard specifies that vision capable of resolving a 1' viewing angle is normal vision standard, recorded as 5 points, i.e., 5.0, corresponding to 1.0 vision recorded in decimal places, 6/6 or 20/20 vision recorded in fractional places. Optotypes used in vision standards include letter optotypes, number optotypes, picture optotypes, etc., each of which has a fixed design standard. Taking the common "E" letter optotype as an example, the design adopts a square "E" optotype with three strokes of equal length, and each stroke or gap is one fifth of the side length of the square, as shown in FIG. 1. When the optotype is used for vision detection, a fixed distance is required between a tested person and the optotype in the national standard, and the optotype is also fixed, for example, the national standard GB 11533-2011. For ease of operation, only the far vision inspection standard of 5m and the near vision inspection standard of 25cm, that is, only the fixed design standard of the optotype "E" and the corresponding vision test value are specified in the standards. Meanwhile, the standard also requires that the measured person and the sighting target have the same level and are right opposite to direct vision. Wherein the ' level equal height ' is just right against the direct vision ' requires that the tested person must be equal in height to the sighting mark level. As shown in fig. 2, the height of the human eye from the ground in plan view is E1, and the height of the center (white dot) of the optotype "E" (black) from the ground is E2. The expression of the level contour is: e1 =e2 equation 1 The expression for direct vision is: Equation 2 Therefore, if the distance and/or viewing angle between the subject and the optotype are different from those in the standard during the vision test, an accurate vision test value cannot be obtained. Taking the viewing angle as an example: ① The vertical included angle between the testee and the sighting target is that the testee must be equal to the center of the sighting target, otherwise, there is no way to ensure that each stroke or gap is 1' visual angle in the vertical direction. Taking the horizontal optotype (E with the opening facing right) as an example, as shown in fig. 3, the height of the left white testee is E1' (x, y), the height of the right gray standard testee is E1 (x, y), and the heights are equal to each other, as shown in formula 3: y E1＝yE1′ equation 3 The center of the new optotype E2' (x, y) corresponding to the white person under test is higher than the center of the standard optotype E2 on the right by Δe, that is, the white person under test is not level with the new optotype center: yE2′-yE2=△e and y E1＝yE1′,yE2＝yE1 equation 4 ∴yE2′-yE1′=△e At this time, the gap included angle of the new optotype is smaller than 1', that is, α ' <1', which does not satisfy the standard of the optotype, and accordingly, an accurate vision test value is not obtained when vision test is performed. ② The horizontal included angle between the testee and the sighting target is that the testee must be vertical to the sighting target, otherwise, there is no way to ensure that each stroke or gap is 1' visual angle in the horizontal direction. Taking the vertical optotype (E with the opening facing upwards) as an example, as shown in fig. 4, the height of the left white testee is E1 '(x, y), the height of the right gray standard testee is E1 (x, y), the two are equal in height, and the two people have a horizontal difference Δe' from the standard optotype, as shown in formula 5: Equation 5 For the left white subject, his horizontal vertical and equal-height optotype is E2' (x, y), so the white subject is equal-height with the optotype E2 (x, y) corresponding to the gray standard small person in fig. 4, but has horizontal parallax, that is: Equation 6 If the standard optotype E2 is still used for the white testee, there is a horizontal parallax, that is, α ' +.α, and α ' <1', which does not satisfy the standard of the optotype, and accordingly, an accurate vision test value is not obtained when vision test is performed. ③ When the horizontal included angle and the vertical included angle exist between the testee and the sighting target, whether the sighting target is the horizontal sighting target or the vertical sighting target, a standard gap exists or the strokes do not accord with the design standard of the 1' visual angle, and accordingly, an accurate visual detection value cannot be obtained when visual detection is carried out. Disclosure of Invention The application aims to provide a vision testing method and a vision testing system based on any space position, which are used for solving the te