JP2012239566A - Measuring apparatus for glasses, and three-dimensional measuring apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a measuring apparatus for glasses which performs measurements for a distance between the cornea and glasses and so forth without applying load to a patient.SOLUTION: The measuring apparatus (10) for glasses includes: a photographing section (12) which photographs the patient wearing glasses (20) for which an index mark (SC) is attached to the frame (23) of glasses; and an operation section (14) which obtains the apex of the eye ball of the patient which has been photographed by the photographing section, and at the same time, calculates the distance (KG) between the cornea and glasses, which is the distance between the lens (21) of glasses and the apex (KP) of the eye ball of the patient. conforming to the index mark (SC).

Description

  The present invention relates to a spectacle measuring apparatus and a three-dimensional measuring apparatus that measure the position and angle of a subject's eyes and the eye position with respect to spectacles worn by the subject.

  When creating near-sighted or far-sighted spectacles using a lens lens (raw eyeglass lens) single focus lens, the distance between pupil centers, the distance between corneal glasses, and the viewing angle (eye position), etc. Need to be measured. In addition, when using a progressive multifocal lens in which myopia and hyperopia are mixed in a single spectacle lens, a so-called progressive lens, information such as the pupil center distance, the corneal spectacle distance, and the line-of-sight angle is particularly important. . That is, the progressive multifocal lens is required to accurately measure the viewing angle for distance and near according to the use environment of the subject.

  For the measurement of the distance between the pupil centers and the distance between the cornea glasses, a method in which the measurer applies a ruler in the vicinity of the subject's eye to perform a visual measurement, or a face image or side surface of the subject's front using the apparatus After acquiring the face image, a method of measuring the distance between the pupil centers and the distance between the cornea glasses is performed. Patent Document 1 proposes a method of measuring a pupil center distance, a corneal spectacle distance, a line-of-sight angle, and the like using a dedicated eye position measurement device.

  However, an error is likely to occur in the measurement of the distance between the pupil centers and the distance between the corneal glasses by the eye of the measurer. In addition, when using a dedicated eye position measurement device, it is necessary to attach a dedicated accessory device to the spectacle frame, and it is necessary to prepare a device for analyzing the captured image, which increases capital investment. There is.

JP 2007-216049 A

  In view of the above problems, the present invention provides a spectacle measuring device and a three-dimensional measuring device that measure the distance between pupil centers, the distance between corneal spectacles, and the line-of-sight angle without imposing a load on the subject.

  A spectacles measuring apparatus according to a first aspect obtains a photographing unit that photographs a subject wearing spectacles with an index mark attached to a spectacle frame, and obtains the apex of the eyeball of the subject photographed by the photographing unit. A calculation unit that calculates the distance between the corneal glasses between the spectacle lens of the spectacles and the apex of the eyeball of the subject based on the index mark.

  A measuring apparatus for spectacles according to a second aspect includes an imaging unit that images a subject from the front, a storage unit that stores an average diameter of the iris, and a maximum iris iris diameter imaged by the imaging unit. And a calculation unit that calculates a pupil center distance, which is a distance between pupils of both eyes of the subject, based on the average diameter stored in the storage unit and the determined maximum diameter of the iris.

  A measuring apparatus for spectacles according to a third aspect includes a photographing unit that firstly photographs a subject looking far away from the front and secondly photographing a subject looking nearer than far away from the front, a first photographing, The first diameter in the horizontal direction and the second diameter in the vertical direction of the iris of the eyeball of the subject photographed in the second photographing are obtained, and the first and second diameters in the first photographing and the second photographing. And a computing unit that computes a line-of-sight angle when the subject looks far and when he looks near, based on the first diameter and the second diameter.

  The three-dimensional measuring apparatus according to the fourth aspect measures the distance between the corneal spectacles between the apex of the eyeball of the subject and the spectacle lens, or the distance between the pupil centers that is the distance between the pupils of both eyes of the subject. The three-dimensional measuring apparatus captures the subject in a state in which the subject wears spectacles having a light-transmitting spectacle lens and the subject in a state in which the subject is not wearing glasses. An imaging unit that performs two imaging and an arithmetic unit that calculates an intercorneal spectacle distance or a pupil center distance based on a difference in images between the first imaging and the second imaging.

  According to the spectacles measuring apparatus and the three-dimensional measuring apparatus of the present invention, it is possible to acquire measurements such as the pupil center distance, the corneal spectacle distance, and the line-of-sight angle, and appropriate spectacle adjustment is possible.

1 is a diagram illustrating a tablet terminal 10. 2 is a diagram showing a configuration of eyeglasses 20. FIG. It is a face side image FL in which the subject wears spectacles 20. It is a flowchart of the measuring method of the forward inclination angle (theta) of the rim | limb 22, and the distance KG between cornea glasses. 5 is a schematic diagram showing a positional relationship between a face side image FL, a scale MK, and a temple 23. FIG. It is the schematic diagram which showed the measuring method which measures the distance KG between cornea glasses, when image | photographed from diagonally backward. It is a flowchart of the measuring method of distance PD between pupil centers. It is the figure which showed the face front image FA of both eyes vicinity. It is a flowchart which acquires line-of-sight angle (psi). (A) is the figure which showed the position of the iris KS and the pupil in the gaze direction of the far direction FP. (B) is the figure which showed the position of the iris KS and the pupil in the gaze direction of the near direction NP. The flowchart of the line-of-sight angle (psi) using the gyro sensor part 13 is shown. It is a measurement conceptual diagram of the line-of-sight angle ψ using the gyro sensor unit 13. FIG. 3 is a diagram of photographing a subject with the three-dimensional measuring apparatus 100. It is an example of the spectacles by which the alignment sticker as a parameter | index marker was affixed. 1 is a conceptual diagram of a three-dimensional position measuring apparatus 100. FIG.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the drawings. It should be noted that the scope of the present invention is not limited to these forms unless otherwise specified in the following description.

(First embodiment)
In the first embodiment, a mobile tablet terminal with camera (hereinafter referred to as a tablet terminal) 10 is used. FIG. 1 is a diagram illustrating a general tablet terminal 10. The tablet terminal 10 includes a display unit 11 such as a liquid crystal display, a camera unit 12, a gyro sensor unit 13, a calculation unit 14, and a storage unit 15. The camera unit 12 is arranged at two locations, the first camera unit 12a is arranged on the surface on the opposite side of the display unit 11, and the other second camera unit 12b is arranged on the surface on the display unit 11 side. Yes. The camera unit 12 uses a CCD or CMOS as a light receiving element 123 (see FIGS. 5 and 6) in addition to the photographing lens 121.

  The tablet terminal 10 has a portable size and is equipped with a plurality of functions such as a telephone function. The tablet terminal 10 can be installed with a plurality of application programs. The application operates on the calculation unit 14 of the tablet terminal 10 and can perform various calculation processes. The tablet terminal 10 used in the first embodiment is not limited to the tablet terminal 10 shown in FIG. 1 and may be a camera in which an application can be installed.

  The camera unit 12 can shoot by switching the shooting direction to the display unit 11 side or the direction opposite to the display unit 11. The first camera unit 12a can shoot an object on the side opposite to the surface of the display unit 11 while confirming the object on the display unit 11, and the second camera unit 12b can capture an object on the display unit 11 side (e.g. ) On the display unit 11. The camera unit 12 can perform still image shooting or moving image shooting. The display unit 11 can display an image captured by the camera unit 12 as a still image or a moving image. The calculation unit 14 can perform a number of calculation processes using captured still image or moving image data. The storage unit 15 stores the size of general glasses, the diameter of a general subject's iris, and the like.

  A method for measuring the pupil center distance PD, the corneal spectacle distance KG, the line-of-sight angle ψ, and the like using the tablet terminal 10 will be described.

  FIG. 2 is a diagram showing the configuration of the glasses 20. The spectacles 20 include two spectacle lenses 21 and a spectacle frame 29. The spectacle frame 29 includes a rim 22 that supports the spectacle lens 21, a temple 23 that extends from the rim, and a modern 24 that covers the ear.

<Facial side image photography>
FIG. 3 is a face side image FL in which the subject wears the glasses 20. The measurer asks the subject to wear glasses 20. After adjusting the degree of eyeglasses 20 so as to fit the face of the subject, the measurer takes a facial side image FL with the first camera unit 12a of the tablet terminal 10. In particular, when photographing, the eyeglass iris KS and cornea are photographed together with the glasses 20.

  The measurer attaches the index marker SC to the subject's temple 23 when photographing the facial side image FL. The measurer may attach the eyeglass 20 to the subject after attaching the index marker SC to the temple 23. The marker marker SC is mounted so as to be parallel to the temple 23 of the eyeglass 20 of the face side image FL in the vicinity of the measurement site. This is because of the aberration of the first camera unit 12a of the tablet terminal 10. Further, the index marker SC is arranged so as to fall within the photographing range of the face side image FL. The index marker SC may be arranged so as to overlap the temple 23.

  The indicator marker SC is attached to measure the distance. For this reason, it is only necessary to obtain a high contrast suitable for image processing by the calculation unit 14 of the tablet terminal 10, and a jig attached with a patterned seal or clip or the like may be used. For example, the index marker SC has a scale MK at three locations with a width of 20 mm and an interval T of 10 mm. The three scales MK are used to determine whether the eyeglass 20 frame is taken from the right side or taken from an oblique direction. In FIG. 2, the scale MK for each distance of 10 mm is used, but the scale MK formed with a different color scheme for every 10 mm may be used. The calculation unit 14 recognizes the scale MK or the designated color scheme and calculates the location, angle, and distance T between the scales MK of the index marker SC.

  In general, the spectacle lens 21 is designed to best correct the aberration of the refractive system when the line of sight coincides with the principal axis of the spectacle lens 21. When viewing from a distance, the line of sight is inclined downward by 5 to 10 ° with respect to the horizontal line. Therefore, it is known that the forward tilt angle θ of the far-sighted glasses (myopic glasses) needs to give the rim 22 a tilt angle of 5 to 10 ° in order to make the normal visual line coincide with the optical axis of the spectacle lens 21. Yes. It is known that the forward tilt angle θ of the near eyeglasses (presbyopia eyeglasses) needs to make the rim 22 be inclined at 12 to 15 ° so that the lower side can be easily seen at hand. It is known that the forward tilt angle θ of the bifocal type using a progressive multifocal lens requires the rim 22 to have a tilt angle of 10 to 12 °.

  Further, the corneal spectacle distance KG of the spectacle lens 21 is designed to be about 12 mm to 15 mm. It is known that when the inter-corneal spectacle distance KG is longer than the designed distance, the refractive index of the spectacle lens 21 shifts to the plus side for the subject and feels weak in myopia and strong in hyperopia. It is known that when the intercorneal spectacle distance KG is closer than the designed distance, the refractive index of the spectacle lens 21 shifts to the minus side for the subject and feels strong in myopia and weak in hyperopia.

<Measurement of forward tilt angle θ and corneal spectacle distance KG>
FIG. 4 is a flowchart of a method for measuring the forward tilt angle θ of the rim 22 and the distance KG between corneal glasses. The measurer activates the tablet terminal 10 and selects an application for measuring the forward tilt angle θ of the rim 22 and the corneal spectacle distance KG. The forward tilt angle θ of the rim 22 and the corneal spectacle distance KG are measured as follows.

  In step S <b> 10, the measurer uses the camera unit 12 of the tablet terminal 10 to photograph the face side image FL of the subject. The measurer has already attached an index marker SC having a scale MK parallel to the temple 23. The imaging range is a range around the subject's eye, the range in which the rim 22, the index marker SC, and the temple 23 enter. In addition, shooting is performed with still images or moving images.

  In step S11, the calculation unit 14 of the tablet terminal 10 calculates a distance from the camera unit 12 to the index marker SC (face side image FL). The calculation unit 14 analyzes one frame image of the captured still image or moving image and detects the three-point scale MK of the index marker SC. Then, the distance from the camera unit 12 to the index marker SC is calculated based on the interval of the scale MK. FIG. 5 is a schematic diagram for calculating the distance from the camera unit 12 to the index marker SC. FIG. 5 is a schematic view of the positional relationship between the camera unit 12 and the glasses 20 of the face side image FL photographed from the side, as viewed from above.

  5A, the camera unit 12 of the tablet terminal 10 has a known shooting magnification, and the shooting magnification of the camera unit 12 is registered in the application as a setting value in advance. The interval T of the scale MK is known, and is defined as 10 mm in this embodiment. The computing unit 14 computes a distance y from the camera unit 12 to the index marker SC from the captured image based on the similarity of triangles.

  In step S <b> 12, the calculation unit 14 analyzes one frame image of the captured still image or moving image, and calculates the forward tilt angle θ of the rim 22 of the glasses 20. The calculation unit 14 recognizes the temple 23 and the rim 22 and calculates a forward tilt angle θ formed by the temple 23 and the rim 22.

  In step S13, the calculation unit 14 detects the corneal vertex KP from the shape from the image. As illustrated in FIG. 3, the calculation unit 14 recognizes the iris KS and the corneal shape, and performs image processing on the iris shape and the corneal shape to detect the corneal vertex KP.

  In step S14, the calculation unit 14 detects the rim 22 at a position extending in the horizontal direction from the cornea vertex KP. The calculation unit 14 detects the rim 22 positioned in the horizontal direction from the corneal vertex KP and acquires the position information. There are two ways to obtain the horizontal direction from the corneal vertex KP. The horizontal direction is obtained by considering the direction in which the temple 23 extends as horizontal, and the other is the method in which the horizontal direction is obtained by considering the direction in which the marker marker SC extends as horizontal.

  In step S15, the calculation unit 14 measures the corneal spectacle distance KG from the position of the cornea vertex KP in step S12 and the spectacle lens 21 (or rim 22) in step S13. FIG. 5B is a schematic diagram showing a calculation method of the corneal spectacle distance KG. The corneal spectacle distance KG is calculated using the distance y from the camera unit 12 to the index marker SC obtained in step S11. In the glasses 20, the center distance BB of the rim 22 from the temple 23 is acquired as a known value. The calculation unit 14 is based on the number of pixels of the light receiving element 123 at the interval T of the scale MK, the number of pixels of the light receiving element 123 at the corneal spectacle distance KG, the distance y from the camera unit 12 to the index marker SC, and the center distance BB of the rim. Then, the corneal spectacle distance KG is calculated.

  The tablet terminal 10 can calculate an accurate inter-corneal spectacle distance KG with reproducibility from one face side image FL. Note that the corneal spectacle distance KG is 0 when the rim center distance BB, which is a typical measurement condition, is about 40 mm, and the distance between the temple 23 and the camera unit 12 of the tablet terminal 10 is about 500 mm. It can be measured with an error range of 9 mm.

  FIG. 6 is a schematic diagram showing a measurement method for measuring the distance KG between corneal glasses when taken from an oblique rear side. FIG. 6A is a schematic diagram showing the positional relationship between the face side image FL and the scale MK taken from obliquely behind. In the case of photographing with the camera unit 12 from diagonally rear, in addition to the calculation method shown in FIG. 5, the distance from the camera unit 12 to the index marker SC (facial side image FL) is corrected by the tilt angle from diagonally rear. An operation is necessary. Although not specifically described, the same applies to a case where the image is taken obliquely from the front.

  Since the graduation MK has three points, there are two distances T between the graduations MK. The calculation unit 14 recognizes the distance T between the two scales MK in the face side image FL as the inter-pixel distance t1 and the inter-pixel distance t2 of the light receiving element 123 of the camera unit 12. When the face side image FL is taken obliquely from behind, the number of pixels is different between the inter-pixel distance t1 and the inter-pixel distance t2. The calculator 14 calculates the tilt angle α from the ratio of the inter-pixel distance t1 and the inter-pixel distance t2.

  FIG. 6B is a schematic diagram showing a calculation method of the distance KG between corneal glasses from the oblique direction. Using the flowchart shown in FIG. 4, the calculation unit 14 calculates the intercorneal spectacle distance kg2 from the number of pixels of the intercorneal spectacle distance of the light receiving element 123, and calculates the cornea from the inclination angle α shown in FIG. The eyeglass distance kg2 can be corrected to the corneal eyeglass distance KG.

  When the calculation unit 14 cannot detect the position of the corneal vertex KP, the rim 22 or the scale MK, the measurer uses the touch panel of the display unit 11 of the tablet terminal 10 to allow the measurer to perform the corneal vertex KP, the rim 22 or the scale. It is also possible to calculate a predetermined measurement result by designating MK. In addition, the calculation unit 14 of the tablet terminal 10 performs object tracking (tracking) after detecting the position of the corneal vertex KP or the scale MK with respect to the frame image of the moving image that has been shot. Real-time measurement values can be displayed. The anteversion angle θ of the rim 22 and the corneal spectacle distance KG described above are preferably measured on both the left and right sides of the subject.

<Measurement of pupil center distance PD>
A method of measuring the pupil center distance PD using the tablet terminal 10 will be described.

  FIG. 7 is a flowchart of a method for measuring the pupil center distance PD. The measurer selects an application for measuring the pupil center distance PD of the tablet terminal 10.

  In step S20, the measurer takes a facial front image FA near both eyes. The measurer has the subject gaze at the camera unit 12 of the tablet terminal 10 and shoots the front face image FA. When photographing, the subject may take off the glasses 20 or wear the glasses 20. Further, the measurer takes an image so that the left and right eyes of the subject are simultaneously included. Shooting can be performed with still images or moving images. FIG. 8 is a diagram showing a face front image FA near both eyes.

  In step S21, the calculation unit 14 analyzes the image and detects the iris KS of both eyes. The calculation unit 14 analyzes one frame image of the captured still image or moving image, detects the iris KS of both eyes, and calculates the pupil center DC.

  The iris KS can be detected by the calculation unit 14 detecting a white eyeball from the face front image FA and recognizing the central portion as the iris KS. The calculation unit 14 can accurately detect the edge of the iris KS from the white eyeball adjacent to the iris KS.

  The pupil center DC of one eye is detected by detecting the maximum value of the edge in the X-axis direction, which is the diameter KL of the iris KS, at the edge of the iris KS detected by the calculation unit 14. Can be calculated. The calculation unit 14 also calculates the position of the pupil center DC of the other eye.

  Since the average size of the diameter of the human iris KS is 11 mm, the iris pixel distance KL that is the diameter of the iris KS detected by the calculation unit 14 is converted to 11 mm. The diameter of the iris KS is stored in the storage unit 15. An application for measuring the pupil center distance PD may have an average size of the diameter of the child iris KS.

  In step S22, the pupil center distance PD is calculated. When the calculated positions of the pupil centers DC of both eyes are calculated, the calculation unit 14 calculates the pupil center distance PD from the number of pixels of the light receiving element 123 at the distance between the two pupil centers DC.

  The calculation unit 14 highlights the detected iris KS on the display unit 11 of the tablet terminal 10 and can display the measurement result of the pupil center distance PD and a straight line connecting the two pupil center positions. is there. When the measurer measures the pupil center distance PD with a moving image, the position of the iris KS and the pupil center DC detected by the calculation unit 14 is tracked and the pupil center distance PD measurement result is obtained. And a straight line connecting the two pupil center positions can be continuously displayed in real time. In the present embodiment, the diameter of the iris KS is calculated by detecting the maximum value of the edges of the iris KS in the X-axis direction, and the center of the iris KS is set as the position of the pupil center DC. The position of the pupil center DC may be calculated from a circular shape or an elliptical shape formed at the edge. Further, in the first embodiment, the measurer shoots the front face image FA, but by using the second camera unit 12b on the display side of the tablet terminal 10 (see FIG. 1), the subject is examined. It is also possible to measure the pupil center distance PD by yourself.

<Measurement of gaze angle ψ>
A method for measuring the line-of-sight angle ψ (eye position) using the tablet terminal 10 will be described. The line-of-sight angle ψ is taken from the front direction of the face by the tablet terminal 10. At the time of photographing, the measurer selects an application for measuring the line-of-sight angle ψ, and the measurer performs photographing so that the left and right eyes of the subject are simultaneously included. Shooting may be either a still image shooting or a moving image shooting.

The line-of-sight angle ψ is measured in order to know the line-of-sight direction in the near field work or the far field work. As described above, the progressive multifocal lens needs to be adjusted to an arrangement suitable for the use environment of the subject because a single spectacle lens 21 includes near, far, and intermediate lenses.
The measurer obtains the gaze angle ψ of the subject in a usage situation where the subject needs the glasses 20.

FIG. 9 is a flowchart for obtaining the line-of-sight angle ψ.
In step S30, the measurer captures the distant and near face front images FA. The measurer places the camera unit 12 of the tablet-type terminal 10 in the direction of the line of sight of the subject, asks the subject to gaze, and photographs the front face image FA (FP). In addition, the measurer places the camera unit 12 of the bullet type terminal 10 in the direction of the line of sight of the subject, causes the subject to move the line of sight of the target near the subject, and displays the face front image FA. Take a picture (NP). It is desirable for the subject to take off the glasses 20 when taking a picture. Further, it is desirable for the measurer to take an image so that the left and right eyes of the subject are included at the same time.

  In step S31, the calculation unit 14 analyzes the image and detects the iris KS of both eyes. The calculation unit 14 analyzes one frame image of the captured still image or moving image, detects the iris KS of both eyes, and calculates the pupil center DC. The calculation unit 14 detects the edge of the iris KS of both eyes and calculates the pupil center DC. The calculation unit 14 calculates the shape of the iris KS with the pupil center DC as the center. The iris KS in the eyeball has a different edge shape depending on the viewing direction. FIG. 10A is a diagram showing the positions of the iris KS and the pupil in the viewing direction of the far direction FP. FIG. 10B is a diagram showing the positions of the iris KS and the pupil in the viewing direction of the near direction NP.

  In step S32, the calculation unit 14 calculates the line-of-sight angle ψ. As shown in FIG. 10A, the iris KS in the case of the viewing angle ψ in the far direction FP is in the central part of the spherical eyeball, and the pupil center DC is also in the central part of the eye. In this case, the iris KS of the face front image FA photographed by the camera has a perfect circle that is substantially equal in diameter HA in the horizontal direction and diameter VA in the vertical direction. On the other hand, as shown in FIG. 10B, the iris KS in the case of the line-of-sight angle ψ in the near direction NP is in the lower part of the spherical eyeball, and the pupil center DC is also arranged in the lower part of the eye. In this case, the iris KS of the face front image FA photographed by the camera unit 12 is a horizontally long ellipse in which the vertical diameter VA, which is the diameter in the vertical direction of the iris KS, is shorter than the horizontal diameter HA, which is the diameter in the horizontal direction. The computing unit 14 computes the eccentricity of the first ellipse based on the horizontal diameter HA and the vertical diameter VA of the iris KS when looking far away, and the iris when looking near. The eccentricity of the second ellipse is calculated based on the horizontal diameter HA and the vertical diameter VA of KS. Then, the calculation unit 14 calculates an elliptic ratio between the eccentricity of the first ellipse and the eccentricity of the second ellipse. Then, the calculation unit 14 calculates the line-of-sight angle ψ from the database of the ellipticity ratio of the iris KS and the line-of-sight angle ψ stored in the storage unit 15.

  It should be noted that the iris KS cannot always detect the entire circumference of the edge of the iris KS by the computing unit 14 due to an obstacle such as an upper eyelid or a lower eyelid. The calculation unit 14 can calculate the most suitable circle or ellipse by referring to a database built in the application with respect to the side shape of the iris KS centered on the pupil center DC.

  The calculation unit 14 can calculate the intersection of the line of sight in the far direction FP of the subject and the surface of the spectacle lens 21 from the acquired line-of-sight angle ψ and the inter-corneal spectacle distance KG acquired in the first embodiment. Further, the intersection of the line of sight and the lens surface in the near direction NP of the subject can also be calculated. As a result, the measurer can set the glasses 20 optimal for the subject.

  In this embodiment, the measurer takes the front face image FA, but the subject measures the gaze angle ψ by using the second camera unit 12b on the display side of the tablet terminal 10. It is also possible to do.

<Modification>
As a method for measuring the line-of-sight angle ψ, this modification shows a method using the gyro sensor function of the gyro sensor unit 13 (see FIG. 1) of the tablet terminal 10. The gyro sensor function can detect the angle of the tablet terminal 10. Since the calculation unit 14 can acquire the angle of the tablet terminal 10, the angle of the tablet terminal 10 can be used for an application for measuring the line-of-sight angle ψ. Also in this modification, the measurer and the subject can measure the line-of-sight angle ψ. Next, a method in which the subject himself / herself measures the viewing angle ψ will be described. In this case, the subject can wear the glasses 20 and measure the line-of-sight angle ψ.

  FIG. 11 shows a flowchart of the line-of-sight angle ψ using the gyro sensor unit 13. FIG. 12 is a diagram illustrating a method of measuring the line-of-sight angle ψ using the gyro sensor unit 13.

  In step S40, the subject places the tablet terminal 10 in a state where the near eyeglasses are required. Character information or the like is displayed on the display unit 11 of the tablet terminal 10 and the subject holds the tablet terminal. The subject turns his gaze in the near direction NP (see FIG. 12) in order to see the character information on the display unit 11. The subject looks at the character information on the display unit 11 in a state where the near eyeglasses are necessary, and adjusts the angle of the tablet terminal 10 held by the hand to an angle perpendicular to the line of sight. In general, in order to observe the display unit 11 of the tablet terminal 10 using a liquid crystal panel, a state in which the subject's line of sight is perpendicular to the liquid crystal panel has the highest contrast and is clearly observable. Therefore, the subject can understand whether the tablet terminal 10 is held vertically.

  In step S41, the calculation unit 14 acquires first angle information β. The subject stores the first angle information β, which is an angle optimal for observing the character information, in the calculation unit 14. The first angle information β is stored by an action such as a touch of the touch panel of the display unit 11 of the tablet terminal 10 by the subject.

  In step S42, the subject places the tablet terminal 10 in a state where distance glasses are required. A landscape image or the like is displayed on the display unit 11 of the tablet terminal 10 and the tablet terminal is held at the position of the landscape image that the examinee usually sees. The subject turns his / her line of sight in the far direction FP (see FIG. 12) in order to view the landscape image on the display unit 11. The subject looks at the landscape image of the display unit 11 in the state where the distance glasses are necessary, and adjusts the angle of the tablet terminal 10 held by the hand to an angle perpendicular to the line of sight.

  In step S43, the calculation unit 14 acquires the second angle information γ. The subject stores the second angle information γ, which is the line of sight in the far direction FP, in the calculation unit 14. The storage of the second angle information γ is performed by an action such as the subject touching the display unit 11 of the tablet terminal 10.

  In step S44, the calculation unit 14 calculates the line-of-sight angle ψ. The computing unit 14 can compute the line-of-sight angle ψ from the difference between the first angle information β in step S41 and the second angle information γ in step S43.

  In this modification, character information and landscape are displayed on the display unit 11, but the first angle information β and the second angle while the subject is photographed with a still image or a moving image by the second camera unit 12b. Information γ may be acquired. It is also possible to display angle information or measurement results in real time. Further, in the present modification, more accurate first angle information β is obtained by using information on the line-of-sight angle ψ in the far direction FP and the line-of-sight angle ψ in the near direction NP obtained with the shape of the iris KS shown in FIG. It is also possible to obtain the second angle information γ.

(Second Embodiment)
The second embodiment shows a method of measuring the corneal spectacle distance KG, the pupil center DC, and the pupil center distance PD using a three-dimensional position measurement apparatus. FIG. 13 is a conceptual diagram of the three-dimensional position measuring apparatus 100.

  The three-dimensional position measuring apparatus 100 can photograph the vicinity of the subject's face and acquire the three-dimensional position of the face. The three-dimensional position measurement apparatus 100 includes a camera unit 112, a calculation unit 114, and a storage unit 115. The three-dimensional position measurement apparatus 100 includes a multi-view stereo (MVS (Multi View Stereo)) imaging apparatus or a stereo imaging apparatus. Next, a method for measuring a three-dimensional position in the multi-view stereo photographing apparatus and the stereo photographing apparatus will be described. In the second embodiment, the position of the glasses and the position of the pupil can be measured from the three-dimensional position information.

  In the three-dimensional position measuring apparatus 100, the camera unit 112 acquires and stores a first three-dimensional facial image when the subject is not wearing glasses and a second three-dimensional facial image when the glasses are worn. These images are stored in the unit 115. Then, the calculation unit 114 calculates the three-dimensional position of the glasses by subtracting the first three-dimensional face image from the second three-dimensional face image. The calculation unit 114 performs position matching on the difference between the second three-dimensional facial image and the first three-dimensional facial image in an area excluding the spectacle portion. Accurate three-dimensional measurement can be performed by arranging an index or the like on the eyeglasses 20 as described below at the site to be matched.

  The three-dimensional position measurement apparatus 100 may acquire a three-dimensional image after projecting stripe pattern light in addition to the index. The fringe pattern light is projected so that the three-dimensional position measurement device can easily measure a good three-dimensional position in a face area with less texture. As the fringe pattern light, it is preferable to use light having a wavelength that does not cause the subject to feel dazzling using infrared wavelength light or the like. The three-dimensional position measurement apparatus 100 may acquire a three-dimensional image using not only the stripe pattern light but also the texture pattern light.

  In order to measure the three-dimensional position of the two spectacle lenses of the spectacles used in the second three-dimensional facial image, a measurement method using a spectacle lens that does not transmit light or an alignment sticker on which an index pattern is drawn are attached to the spectacle lens. There is a method of attaching.

  As the spectacle lens that does not transmit light, a spectacle lens made of a material that does not transmit infrared light to the two spectacle lenses 21 is used. Then, the camera unit 112 of the three-dimensional position measurement apparatus 100 acquires a second three-dimensional facial image with infrared light. Thereby, the calculation unit 114 of the three-dimensional position measurement apparatus 100 calculates the difference between the face shape of the subject and the glasses. The spectacle lens 21 formed of a material such as a metal that does not transmit visible light may be used as the spectacle lens that does not transmit light. Further, the spectacle lens 21 that does not transmit light may be provided with a light shielding seal or the like that shields light on the surface of the normal spectacle lens 21 that transmits light. The camera unit 112 of the three-dimensional position measurement apparatus 100 acquires a second three-dimensional facial image with visible light. Thereby, the calculation unit 114 of the three-dimensional position measurement apparatus 100 calculates the difference between the face shape of the subject and the glasses 20.

  FIG. 14 is an example of a light-shielding seal, and an example of glasses with an alignment seal 210 as an index marker. A pattern for measuring position information is printed on the alignment sticker. The alignment seal forms a pattern suitable for measuring a three-dimensional position. The alignment seal 210 may contain dimension lines or a characteristic figure. The alignment seal 210 is affixed to the spectacle lens 21.

  In FIG. 14, an upward triangle 210 </ b> A, a downward triangle 210 </ b> B, and a star shape 210 </ b> C are drawn at predetermined positions on the background of vertical and horizontal grid dimension lines. The alignment seal 201 can be freely attached and detached.

  The three-dimensional position measuring apparatus 100 can measure the three-dimensional position of the glasses from the feature points such as the rim 22, the temple 23, and the modern 24 of the spectacle frame 29. Further, the calculation unit 112 of the three-dimensional position measuring apparatus 100 can also calculate the three-dimensional position of the surface of the spectacle lens 20 from the three-dimensional position of the spectacle frame 29. In addition, the spectacle lens surface can be obtained in a three-dimensional position using other methods such as an object tracking algorithm.

(Stereo shooting device)
In stereo photography, a front face image is photographed by the camera units 112 of the two three-dimensional position measurement apparatuses 100. The two camera units 112 are arranged at two positions parallel to the horizontal direction (X-axis direction), and images the face of the subject from each position. The two camera units 112 are arranged apart from each other by a predetermined interval. When two cameras are used, the subject can be photographed at the same time, and thus there is an advantage that the subject is less likely to be shaken. You may image | photograph again by moving a fixed distance, after image | photographing with one camera part 112. FIG. In addition, the measurement accuracy of the three-dimensional position improves as the distance between the two camera units 112 increases. When one camera unit is used, a method such as a motion stereo method (SFM (structure from motion)) may be used. The motion stereo method is a method of measuring a three-dimensional position from captured images before and after moving while moving one camera.

FIG. 15 is a diagram illustrating a method of acquiring a three-dimensional position by stereo shooting.
In stereo photography, the face of the subject is photographed by two cameras, the first camera unit 112A and the second camera unit 112B. An image captured by the first camera unit 112A can be acquired as the first facial image G1, and an image captured by the second camera unit 112B can be acquired as the second facial image G2. The measurement point P (X, Y, Z) of the face is located at the first face position G1 (X1, Y1) in the first face image G1, and at the second face position G2 (X2, Y2) in the second face image G2. To position. The focal length of the first camera unit 112A and the second camera unit 112B is set as F, and the distance in the X-axis direction between the first camera unit 112A and the second camera unit 112B is set as the inter-camera distance CD. The center of the photographing lens of the first camera unit 112A is the lens center O1, and the center of the photographing lens of the second camera unit 112B is the lens center O2.

  In stereo photography, the calculation unit 114 includes a triangle formed by the lens center O1, the lens center O2, and the measurement point P (X, Y, Z), a first face position G1 (X1, Y1), and a second face position G2 (X2). , Y2) and the triangle formed by the measurement point P (X, Y, Z) are similar, the measurement point P (X, Y, Z) can be calculated.

  In stereo photography, the vicinity of the eye of the subject's face only needs to be photographed. The first camera unit 112A and the second camera unit 112B are configured to detect the three-dimensional position of the glasses 20 and the three-dimensional pupil from the first three-dimensional facial image without the glasses 20 and the second three-dimensional facial image with the glasses. Get the position. Then, the calculation unit 114 calculates the corneal spectacle distance KG, the pupil center DC, and the pupil center distance PD.

(Multi-view stereo shooting)
Multi-view stereo photography can measure a three-dimensional position from a plurality of photographed images. Multi-view stereo shooting is performed by one camera or a plurality of cameras. In multi-view stereo shooting, it is necessary to acquire the camera position in the shot image. The camera position when shooting a plurality of images with one camera is obtained by arranging the same index marker in the shot image. Further, the positions of the plurality of camera units 112 are registered in the storage unit 115 in advance as set values in which the positions of the camera units 112 are known.

  When multi-view stereo shooting is performed with one camera unit 112, the same index marker arranged in a plurality of captured images to be used is used for matching of the plurality of captured images. For this reason, it is desirable to use the alignment seal 210 as shown in FIG. It is also possible to match a plurality of captured images using the triangle 210A, the downward triangle 210B, and the star 210C. In multi-view stereo photography, a first three-dimensional facial image and a second three-dimensional facial image can be acquired using an index marker. Furthermore, a fringe pattern and a texture pattern may be projected on the subject's face to replace the index marker.

  When performing multi-view stereo shooting with a plurality of camera units 112, the position of the camera unit 112 is known, and therefore, the three-dimensional position measurement of the face of the subject can be performed from the captured image of each camera unit 112. it can. As described above, the marker marker can be a flat striped pattern, a texture pattern, or the alignment seal 210 attached to the spectacle lens 21.

  In multi-view stereo shooting, obtain a good 3D shape of the face by performing image enhancement processing (contrast enhancement, histogram adjustment, edge enhancement, etc.) on the facial area you want to measure instead of the entire 3D facial image you have acquired. can do. Also, in multi-view stereo shooting, by setting an area other than the face area as a mask area that is not subjected to image processing, it is possible to increase the accuracy of the three-dimensional position and speed up the image processing.

  In multi-view stereo photography, the first three-dimensional face image and the second three-dimensional face image are processed to calculate the intercorneal eyeglass distance KG, the pupil center DC, and the pupil center distance PD. The pupil center DC and the pupil center distance PD are calculated from the first three-dimensional face image without glasses.

  The calculation method of the corneal spectacle distance KG, the pupil center DC, and the pupil center distance PD by stereo imaging and multi-view stereo imaging with the three-dimensional position measurement device has been described above. In addition, since the stereo shooting and the multi-view stereo shooting shown in the second embodiment can be shot with one camera unit, the tablet terminal 10 shown in the first embodiment can also be shot. For example, the tablet terminal 10 can acquire a three-dimensional facial image of a face by using an application for multi-view stereo shooting, shooting a face from a plurality of locations, calculating a shooting position from an index marker. . The tablet terminal 10 can acquire a three-dimensional facial image by inputting or setting the arrangement interval of the camera unit 12 moved in the horizontal direction using an application for stereo shooting.

DESCRIPTION OF SYMBOLS 10 ... Tablet-type terminal device, 100 ... Three-dimensional position measuring device 11 ... Display part 12, 112 ... Camera part 13 ... Gyro sensor part 14, 114 ... Calculation part 15 ... Memory | storage part 20 ... Glasses 21 ... Glasses lens 29 ... Glasses frame (22 ... Rim, 23 ... Temple, 24 ... Modern)
210 ... Alignment seal DC ... Pupil center KG ... Intercorneal distance KP ... Corneal apex KS ... Iris MK ... Scale PD ... Pupil center distance SC ... Indicator marker

Claims (10)

An imaging unit for imaging a subject wearing glasses with an index mark attached to an eyeglass frame;
An operation for obtaining a vertex of the eyeball of the subject imaged by the imaging unit and calculating a distance between the corneal spectacles between the spectacle lens of the eyeglass and the vertex of the eyeball of the subject based on the index mark And
A measuring apparatus for spectacles. The measuring apparatus for spectacles according to claim 1,
The eyeglass frame includes a temple and a rim;
The indicator mark includes a scale of a predetermined size, the indicator mark is attached to the temple,
The said calculating part is a spectacles measuring device which calculates the distance between the cornea glasses of the said rim | limb and the vertex of the said eyeball based on the scale and the direction of the said temple or the said index mark. The measuring apparatus for spectacles according to claim 2,
The imaging unit images the subject from diagonally forward or diagonally behind the subject,
The scale of the predetermined dimension indicates a first distance and a second distance;
The eyeglass measuring device calculates the distance between the cornea glasses by correcting the inclination between the photographing unit and the eyeglass frame based on the first distance and the second distance. An imaging unit for imaging the subject from the front;
A storage unit for storing an average diameter of the iris;
The maximum diameter of the eyeball of the subject imaged by the imaging unit is obtained, and based on the average diameter stored in the storage unit and the obtained maximum diameter of the iris, A calculation unit for calculating the distance between pupil centers, which is the distance of the pupil of the eye,
A measuring apparatus for spectacles. An imaging unit that first images a subject looking far from the front and second images from the front a subject that is closer to the far side;
The first diameter in the horizontal direction and the second diameter in the vertical direction of the iris of the eyeball of the subject photographed in the first photographing and the second photographing are obtained, and the first diameter and the second diameter in the first photographing are determined. Based on the second diameter and the first diameter and the second diameter at the time of the second imaging, the line-of-sight angle between when the subject looks at the far side and when looking at the near side is calculated. An arithmetic unit;
A measuring apparatus for spectacles. In the measuring apparatus for spectacles of Claim 5,
The calculation unit obtains an eccentricity of the first ellipse of the iris based on the first diameter and the second diameter at the time of the first photographing, and the first diameter and the first at the time of the second photographing. A measurement device for spectacles that calculates the eccentricity of the second ellipse of the iris based on two diameters and performs the calculation based on an ellipticity ratio that is a ratio between the eccentricity of the first ellipse and the eccentricity of the second ellipse . In the three-dimensional measuring apparatus for measuring the distance between the corneal spectacles between the apex of the eyeball of the subject and the spectacle lens, or the distance between the pupil centers of the eyes of both eyes of the subject,
A first photographing for photographing the subject in a state in which the subject wears spectacle lenses that do not transmit light, and a second photographing in which the subject is photographed without wearing the glasses. A shooting unit that performs
A calculation unit that calculates the distance between the corneal glasses or the distance between the pupil centers based on a difference in images between the first imaging and the second imaging;
A three-dimensional measuring apparatus. The three-dimensional measuring apparatus according to claim 7,
The spectacle lens that does not transmit light is a spectacle lens that does not transmit infrared light,
The imaging unit is a three-dimensional measuring apparatus that performs the second imaging with infrared light. The three-dimensional measuring apparatus according to claim 7,
The spectacle lens that does not transmit light is a spectacle lens in which a light shielding portion is formed and an index mark is formed,
The imaging unit is a three-dimensional measuring device that images the index mark. In the three-dimensional measuring apparatus as described in any one of Claims 7-9,
A three-dimensional measuring apparatus including a plurality of the imaging units that images the subject from a plurality of directions.