Patent Grant
10175507
The present invention relates to assembly of a binocular loupe device.
Binocular loupe devices have been widely used in, e.g., medical services (surgical operation, etc.) and precision machining in various other fields as a means for magnifying a surgical region or a work object part. In particular, binocular loupe devices for medical treatment concerned with human life are required to ensure high precision visibility during use.
Typically, as a binocular loupe device, an eyeglass type binocular loupe device in which left and right loupes (magnifiers) are attached to eyeglasses worn by a user (see, for example, Patent Document 1 and Patent Document 2) and a headband type binocular loupe device attached to a headband (belt) worn by a user at his or her head (see, for example, Patent Document 3) are known. Further, the eyeglass type binocular loupe device includes a lens fitting type in which loupes are directly fixed to the lenses of the eyeglasses (see, for example, Patent Document 1) and a front hanging type in which loupes are attached detachably or undetachably to the frame of eyeglasses by means of a clip or an arm so as to be positioned directly in front of the lenses of the eyeglasses (see, for example, Patent Document 2).
As illustrated in
Generally, in human eyes, when the line of sight (axis of vision) directed to the front in a far vision state is shifted to a near vision state for reading or handwork, each eyeball is turned downward as illustrated in
Further, in human eyes, when left and right lines of sight (axes of vision) directed to the front in parallel with each other in a far vision state are shifted to a near vision state for reading or handwork, eyeballs come close to each other or converged as illustrated in
The present inventor has already developed a binocular loupe manufacturing method capable of determining the downward inclination angle and inward inclination angle for attachment of the loupe to the carrier lens (see, for example, Patent Document 4). In this method, a user is made to wear a frame before attachment of the loupe to the carrier lens, the face of the user in a working posture is photographed from the work object point, and obtained image data and distances measured from several work object points are used to determine the downward inclination angle and inward inclination angle of the loupe.
r=90−(90−β)−α=β−α.
In Patent Document 4, the user in the working posture is photographed from a side, and the inclination angle of the head of the user or carrier lens 4 with respect to the vertical direction is measured from the obtained image data, whereby the angle α is obtained.
Patent Document
However, like general glasses lenses, the carrier lens 4 of the binocular loupe device 1 is inclined forward at a predetermined angle with respect to the front direction of the face in a fitted state so as to make the line of sight of the user and a lens optical axis coincide with each other. In addition, the forward inclination attachment angle may vary slightly for each user. Further, the hanging position of the temple 7 of the frame 2 may vary for each user, so that the carrier lens 4 is not always retained parallel (horizontal direction in
Further, the attachment position of each loupe 5 on the carrier lens 4 is preferably set such that the optical axis of the loupe 5 coincides with the line of sight of a user who looks at the work object point P in the working posture. However, a human's face is not symmetrical, so that in many cases, the frame 2 is somewhat inclined to the left or right even when the user faces forward and even when the height positions of the left and right pupils are the same. Further, the center position of the frame 2 in the left-right direction does not always coincide with the center position of the face, and thus the inward approaching amounts of the left and right eyes in a near vision state differ from each other.
The present invention has been made in view of above problems of the conventional techniques, and an object thereof is to provide a binocular loupe device assembling method capable of attaching a loupe with high precision in accordance with the line of sight of a user who looks at a work object point in a near vision state in a working posture in which his or her head is inclined forward.
More specifically, the object is to provide a binocular loupe device assembling method capable of measuring the forward inclination angle of the head of the user in the working posture with higher precision and thus of locating the loupe at a more correct downward inclination angle.
Another object of the present invention is to provide a method capable of determining the attachment position of the loupe with higher precision and comparatively easily in the assembly of the binocular loupe device and a system therefor.
Still another object of the present invention is to provide a loupe attachment assisting tool suitable for determining the attachment position of the loupe with higher precision and with ease in the assembly of the binocular loupe device.
According to a first aspect of the present invention, there is provided a loupe attachment assisting tool for use in attaching a pair of left and right loupes corresponding to the left and right eyes of a user at predetermined positions of a holder worn on the head or face of the user, the loupe attachment assisting tool including a transparent and flat plate member having a substantially rectangular shape, wherein the plate member has an attachment part for removably fixing the plate member to the holder, and the plate member has such a size that the pupils of the left and right eyes are positioned within a plane of the plate member when the head of the user in a near vision state is viewed from a work object point on near lines-of-sight of the left and right eyes of the user in a state where the holder to which the plate member is fixed by the attachment part is worn on the head or face of the user.
With the above configuration, pupil positions of the left and right eyes of the user on the plane of the plate member can be identified, making it possible to easily determine the loupe attachment position in accordance with the pupil positions of the user.
In one embodiment, the attachment part is configured to fix the plate member to the holder such that the plane of the plate member is orthogonal to a far line of sight of the user who wears the holder.
In another embodiment, the plate member has a substantially rectangular frame line formed along the peripheral edge thereof.
In one embodiment, the frame has a higher reflectance than the surroundings.
In another embodiment, the frame has a white or light color.
According to a second aspect of the present invention, there is provided a method for determining an attachment position of a pair of left and right loupes to be attached to a holder worn on the head or face of a user so as to correspond to the left and right eyes of the user, the method including: a step of preparing the holder fitted with the above-described loupe attachment assisting tool of the present invention; a step of acquiring a first image including the whole plate member as the loupe attachment assisting tool and including left and right pupils of the user in a near vision state within a plane of the plate member by photographing the face of the user in a near vision state who wears the holder at his or her head or face from a work object point on near lines of sight of the left and right eyes; a step of measuring, on the first image, coordinate positions of respective vertexes of the plate member and coordinate positions of the respective left and right pupils in the near vision state; and a step of determining an attachment position and/or attachment angle of the loupe on the plane of the plate member by calculating coordinates of points at which lines of sights of the user directed toward the work object point pass through the plate member based on the measured coordinate positions of respective vertexes of the plate member and the coordinate positions of the respective left and right pupils.
By thus applying arithmetic processing to the first image, the pupil positions of the left and right eyes of the user in a near vision state on the plane of the plate member as the loupe attachment assisting tool can be identified, making it possible to easily determine the loupe attachment position and/or loupe attachment angle in accordance with the pupil positions of the user.
In one embodiment, in the step of determining the loupe attachment position, coordinate positions of respective vertexes of a virtual plate member before being projected on a plane of the first image, which is obtained by rotating the plate member on the first image about a straight line passing through the centers of the left and right pupils such that the plane of the plate member faces directly forward are calculated based on the measured coordinate positions of the respective vertexes of the plate member, and based on the calculated coordinate positions of the respective vertexes of the virtual plate member, the loupe attachment position on the plane of the plate member is determined.
In another embodiment, the loupe attachment position determination method further includes a step of acquiring a second image including the whole plate member and including the left and right pupils of the user in a far vision state within the plane of the plate member by photographing the face of the user in a far vision state who wears the holder at his or her head or face from the front; and a step of measuring, on the second image, coordinate positions of respective vertexes of the plate member and coordinate positions of the respective left and right pupils in the far vision state.
In one embodiment, in the step of determining the loupe attachment position, a conversion matrix for converting three-dimensional coordinate positions of the respective vertexes of the plate member before being projected on the plane of the first image into the coordinate positions of the respective vertexes of the plate member on the plane of the first image is calculated based on the measured coordinate positions of the respective vertexes of the plate member and an actual dimension of the plate member, and an inverse conversion matrix of the conversion matrix is used to calculate the three-dimensional coordinate positions from the coordinate positions of the respective vertexes on the plane of the plate member.
In another embodiment, in the step of determining the loupe attachment angle, a downward inclination angle and/or inward inclination angle of the near line of sight with respect to a far line of sight of the user are determined.
In one embodiment, the direct distance between the work object point and the plane of the plate member and horizontal distance therebetween are measured, and the downward inclination angle is determined based on the direct distance, horizontal distance, and a forward inclination angle of the head of the user.
In another embodiment, based on the coordinate positions of the respective vertexes of the plate member on the first image and three-dimensional coordinate positions of the respective vertexes of the plate member before being projected on the plane of the first image, the rotation angle between a plane including the plate member on the first image and a plane including the plate member before being projected on the plane of the first image is calculated to determine the downward inclination angle.
In another embodiment, the direct distance between the work object point and the plane of the plate member and the inward approaching amounts of the left and right pupils of the user on the plane of the plate member are measured, and the inward inclination angles of the respective left and right eyes are determined based on the measured direct distance and inward approaching amounts.
In one embodiment, the holder includes a frame worn on the face of the user and a carrier lens fitted to the frame, and the loupe is attached to the carrier lens.
In another embodiment, the holder includes a frame worn on the face of the user and a support part extending to the front from the frame, and the loupe is supported by the support part.
In still another embodiment, the holder includes a headband worn on the head of the user and a support part extending to the front from the frame, and the loupe is supported by the support part.
According to a third aspect of the present invention, there is provided a system for determining an attachment position of a pair of left and right loupes to be attached to a holder worn on the head or face of a user so as to correspond to the left and right eyes of the user, the system including: a camera; and an arithmetic processing device for processing a image photographed by the camera, wherein the arithmetic processing device applies arithmetic processing to a first image including the whole plate member as the loupe attachment assisting tool and including left and right pupils of the user in a near vision state within a plane of the plate member, which is acquired by photographing, using the camera, the face of the user in a near vision state who wears the holder fitted with the above-described loupe attachment assisting tool of the present invention at his or her head or face from a work object point on near lines of sight of the left and right eyes to measure, on the first image, coordinate positions of respective vertexes of the plate member and coordinate positions of the respective left and right pupils in the near vision state and calculates coordinates of points at which near lines of sights of the user directed toward the work object point pass through the plate member based on the measured coordinate positions of respective vertexes of the plate member and coordinate positions of the respective left and right pupils to determine an attachment position and/or attachment angle of the loupe on the plane of the plate member.
With the above configuration, the pupil positions of the left and right eyes of the user in a near vision state on the plane of the plate member as the loupe attachment assisting tool can be identified, making it possible to easily determine the loupe attachment position and/or loupe attachment angle in accordance with the pupil positions of the user.
In one embodiment, the arithmetic processing device calculates coordinate positions of respective vertexes of a virtual plate member before being projected on a plane of the first image, which is obtained by rotating the plate member on the first image about a straight line passing through the centers of the left and right pupils such that the plane of the plate member faces directly forward based on the measured coordinate positions of the respective vertexes of the plate member and determines the loupe attachment position on the plane of the plate member based on the calculated coordinate positions of the respective vertexes of the virtual plate member.
In another embodiment, the arithmetic processing device processes a second image including the whole plate member and including the left and right pupils of the user in a far vision state within the plane of the plate member, which is acquired by photographing, by the camera, the face of the user in a far vision state who wears the holder at his or her head or face from the front and measures, on the second image, coordinate positions of respective vertexes of the plate member and coordinate positions of the respective left and right pupils in the near vision state.
In still another embodiment, the arithmetic processing device calculates a conversion matrix for converting three-dimensional coordinate positions of the respective vertexes of the plate member before being projected on the plane of the first image into the coordinate positions of the respective vertexes of the plate member on the plane of the first image based on the measured coordinate positions of the respective vertexes of the plate member and an actual dimension of the plate member and uses an inverse conversion matrix of the conversion matrix to calculate the three-dimensional coordinate positions from the coordinate positions of the respective vertexes on the plane of the plate member.
In one embodiment, the arithmetic processing device determines a downward inclination angle and/or inward inclination angle of the near line of sight with respect to a far line of sight of the user.
In another embodiment, the arithmetic processing device determines the downward inclination angle based on the direct distance between the work object point and the plane of the plate member, horizontal distance therebetween, and a forward inclination angle of the head of the user.
In another embodiment, the arithmetic processing device calculates the rotation angle between a plane including the plate member on the first image and a plane including the plate member before being projected on the plane of the first image based on the coordinate positions of the respective vertexes of the plate member on the first image and three-dimensional coordinate positions of the respective vertexes of the plate member before being projected on the plane of the first image to determine the downward inclination angle.
In another embodiment, the arithmetic processing device determines the inward inclination angles of the respective left and right eyes based on the direct distance between the work object point and the plane of the plate member and the inward approaching amounts of the left and right pupils of the user on the plane of the plate member.
According to a fourth aspect of the present invention, there is provided an assembling method for a binocular loupe device provided with a pair of left and right loupes to be attached to a holder worn on the head or face of a user so as to correspond to the left and right eyes of the user, the assembling method including: a step of determining an attachment position and/or attachment angle of the loupe with respect to the holder according to the above-described loupe attachment position determination method of the present invention; and a step of attaching the loupe to the holder according to the determined attachment position and/or attachment angle.
With the above configuration, the binocular loupe device can be assembled so as to be attached to the holder according to a proper attachment position and/or attachment angle.
In one embodiment, the holder includes a frame worn on the face of the user and a carrier lens fitted to the frame, and the loupe is attached to the carrier lens.
In another embodiment, the holder includes a frame worn on the face of the user and a support part extending to the front from the frame, and the loupe is attached to the support part so as to be supported thereby.
In still another embodiment, the holder includes a headband worn on the head of the user and a support part extending to the front from the frame, and the loupe is attached to the support part so as to be supported thereby.
Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. Throughout the accompanying drawings, the same or similar reference numerals are used to designate the same or similar components.
The camera 22 is used for photographing a frame 25 and the face of a user U wearing the frame 25 before attachment of the left and right loupes from the front side. A measurement assisting plate 26 is fixed to the front surface of the frame 25 as a loupe attachment position determination assisting tool suitable for determining the loupe attachment position. In the present embodiment, a surgeon who performs a surgical operation at a work object point P can be assumed as the user U.
Photographing using the camera 22 is performed with the optical axis of the camera 22 directed obliquely upward toward the face of the user U in a working posture in which his or her head is inclined forward at an angle α from the work object point P as denoted by the arrow 27 of
In the present embodiment, the image processing program 43c is a cascade classifier that classifies an object to be identified by subdividing the same from superordinate categories to subordinate categories and identifies the face or eyes from an image of the user photographed by the camera 22. Thus, image processing program 43c includes a face detection cascade file 43e and an eye detection cascade file 43f that store therein features of faces and eyes, respectively, through learning.
As illustrated in
A rectangular frame line 53 having a constant width is formed over the entire periphery of the measurement assisting plate 26 excluding the cut 52. The frame line 53 is preferably formed of a paint having high reflectance for strobe light emitted at photographing or a light-colored (white, etc.) material so as to be clearly distinguishable from the surroundings.
The measurement assisting plate 26 is removably fixed to the front surface of a bridge 8 of the frame 25 using an adequate attachment means such as a screw 54. The measurement assisting plate 26 is disposed such that upper and lower sides 51a and 51b thereof are in parallel with the horizontal direction of the frame 25, that the center position thereof in the left-right direction coincides with that of the frame 25, and that the plane thereof is orthogonal to a front view direction 55 of the frame 25. In another embodiment, the measurement assisting plate 26 can be removably fixed to the bridge 8 of the frame 25 using another attachment means such as a clip.
The vertical dimension of the measurement assisting plate 26 and the attachment position thereof to the frame are preferably set such that the upper side 51a is located above the upper end of a rim 3 of the frame 25 when the frame 25 is viewed from the front and that the lower side 51b is positioned below the lower end of the rim 3 when the near line-of-sight direction is viewed in the opposite direction from an obliquely downward side, that is, when the user in the working posture is viewed obliquely upward from the work object point P. The horizontal dimension of the measurement assisting plate 26 is preferably set such that left and right sides 51c and 51d are positioned near the left and right outer ends of the rim 3 and at least outside of the left and right pupils of the user when the frame 25 is viewed from the front and near line-of-sight direction is viewed in the opposite direction.
With the above configuration, even when the frame 25 that the user wears is photographed from any of the directions of the arrows 27 and 28 shown in
As illustrated in
The flowchart of
First, the frame 25 with measurement assisting plate 26 to which a loupe is yet to be attached is prepared (step S1). Then, the user is made to wear the frame 25, and the face and frame 25 are photographed by the camera 22 (step S2). Image data obtained through photographing is sent from the camera 22 to the computer 23 over the communication cable 24 and then processed (step S3). The computer 23 calculates the positions of the respective left and right pupils on the image and downward inclination angle r and inward inclination angles p and q for attachment of the loupe from the image data output from the camera 22 and input data input through the input device 42 (step S4).
Further, the computer 23 determines the loupe attachment position on the carrier lens 4 based on the image data and input data (step S5). Then, based on the determined loupe attachment position, downward inclination angle r, and inward inclination angles p and q, a loupe attachment hole is formed in the carrier lens 4 of the frame 25 after removal of the measurement assisting plate (or a frame 25 having the same structure as the foregoing one but not attached with the measurement assisting plate 26) (step S6). Finally, the left and right loupes are inserted to the respective loupe attachment holes and fixed thereto, whereby the binocular loupe device is completed (step S7).
Hereinafter, the respective steps of the assembling method will be described more in detail. In step S1, the measurement assisting plate 26 is attached to the frame of the type and size that the user uses in the binocular loupe device in actual use in the manner as described above using
In Step S2, a first photographing and a second photographing are performed. In the first photographing, as denoted by the arrow 27 of
The photographing is performed by the computer 23 controlling the operation of the camera 22. In the computer 23, the central control section 43 executes the imaging program 43a to control the optical system 33 of the camera to thereby focus on a center point O (
The computer 23 displays the image received from the camera 22 on the monitor section 41. From the displayed image on the monitor section 41, the operator of the loupe attachment position determination system 21 can input an instruction necessary for adjustment of a capturing range and position of the image captured by the camera 22 and adjustment of a focal length through the input device 42. The computer 23 controls the camera 22 according to the instruction to adjust the image displayed on the monitor section 41.
After the image on the monitor section 41 is satisfactorily adjusted, the operator of the computer 23 instructs the camera 22 to perform photographing, i.e., release the shutter. The camera 22 receives the photographing instruction from the operator by way of the computer 23 and, in quick response to this, activates the strobe light emitting unit 32 and emits strobe light for photographing. The photographed image is converted into an electrical signal by the imaging device 34 of the camera 22 and output, and image data corresponding to the electrical signal is stored in the image memory 35 by the control section 31.
In step S3, when the operator inputs an instruction to perform image processing, the central control section 43 of the computer 23 executes the user interface program 43b to display a user interface window on the monitor section 41.
When the operator clicks an “OPEN IMAGE FILE” button on the user interface window, the image data stored in the image memory 35 of the camera 22 are displayed in a list at a predetermined display position (not illustrated) on the monitor section 41. The operator selects specific image data from the list, and the selected image data is read out from the image memory 35 by the central control section 43 and displayed in the image display area IM as illustrated in
Then, in step S4, the operator can select predetermined processing on the user interface screen. For example, when the operator checks a “PERFORM PUPIL DETECTION” button and clicks an “ANALYSIS START” button, the central control section 43 of the computer 23 executes the image processing program 43c and then analyzes the image displayed in the image display area IM to detect the positions of the pupils on the image. When the operator checks a “PERFORM MARKER DETECTION” button and clicks the “ANALYSIS START” button, the central control section 43 of the computer 23 executes the image processing program 43c and then analyzes the image displayed in the image display area IM to detect the position of the center point O of the measurement assisting plate 26.
In the first stage, the central control section 43 uses the face detection cascade file 43e to perform face detection by determining whether a target to be identified on the image in the image display area IM corresponds to the face of the user according to image features peculiar to a face. In the second stage, the central control section 43 subdivides the target to be identified and uses the eye detection cascade file 43f to perform eye detection by determining whether a target to be identified on the image corresponds to the eye of the user according to image features peculiar to an eye.
In a third stage, the central control section 43 detects the contour of an iris by binarizing a detection image of the eye. In a fourth stage, the central control section 43 performs morphology processing to detect a rectangle having the maximum brightness and, thereby, the computer 23 detects the coordinate position (XR, YR) of the center of the right pupil of the user and coordinate position (XL, YL) of the center of the left pupil and displays them on the user interface window. In this case, for example, a point at the upper left corner of the image display area IM is set as a coordinate origin O.
In the first stage, the central control section 43 uses the face detection cascade file 43e to perform face detection to thereby narrow down the area where the measurement assisting plate 26 may exist. In the second stage, the central control section 43 converts the face detection image into polylines and extracts, from objects each having four corners, an object in which the angle of each of the four corners is near 90° to thereby recognize the measurement assisting plate 26.
Then, in the third stage, the computer 23 displays the coordinate position of the center point O of the thus recognized measurement assisting plate 26 and a scale in the image display area IM. In the present embodiment, the scale indicates correspondence between 1 mm and the number of pixels in the image, and the central control section 43 calculates the scale based on the actual size of the measurement assisting plate 26 previously input in the computer 23.
Then, the computer 23 executes the analysis program 43d. The analysis program 43d uses the center positions of the left and right pupils and the position of the center point of the measurement assisting plate 26 detected in the processing of
As described using
As described above, the distances M and N can be measured using, e.g., a measuring means. The distance M can also be measured by a laser measurement device, using a laser beam irradiated onto the center point O of the measurement assisting plate 26 from the work object point P. Further, in addition to the above actual measurement, the distance M can be calculated according to the following expression from a focal length f of the optical system of the camera 22, the actual lateral dimension of the measurement assisting plate 26, and an image size on the imaging surface (i.e., imaging device) of the camera 22: M={f×(actual size of measurement assisting plate 26)}/(image size on the imaging surface)
The forward inclination angle α of the head can be calculated as follows.
Further, it is assumed here that a virtual measurement assisting plate 26′ whose plane faces directly forward with respect to the work object point P is disposed such that the center point O coincides with the center point of the actual measurement assisting plate 26. In
Thus, the height dimension a of the trapezoidal measurement assisting plate 26 displayed on the first image, the length b1 of the upper side thereof, and the length b2 of the lower side thereof are represented as follows:
a=Y1+Y3
b1=X1+X2
b2=X3+X4
On the other hand, the length a′ of the vertical side of the original rectangular measurement assisting plate 26 and length b′ of the horizontal side thereof are represented as follows:
a′=Y1′+Y3′
b′=X1′+X2′
The forward inclination angle α can be calculated according to the following expression using the values b1, b2, a′, and b′, where M denotes the linear distance between the work object point P and the center point O of the measurement assisting plate 26:
α=sin−1{(1/b1−1/b2)×b′/a′×M}
Details of this expression will be described below.
(1) Assuming that the horizontal length of the vertical side having the length a′ in an inclined state is ΔL when the measurement assisting plate 26 is inclined forward, the forward inclination angle α is represented by the following expression:
α=sin−1(ΔL/a′)
(2) Here, a′ is a known value, so that when ΔL is divided into ΔL1 and ΔL2 at the center point O of the measurement assisting plate 26, the following relationship is satisfied (
tan θ1=(b1/2)/N=(b′/2)/(N+ΔL1)
∴ΔL1=(b′/b1−1)×M
tan θ2=(b2/2)/N=(b′/2)/(N−ΔL2)
∴ΔL2=(1−b′/b2)×N
(3) Thus, ΔL can be calculated as follows:
ΔL=ΔL1+ΔL2
={(b′/b1−1)+(1−b′/b2)}×N
={(1/b1−1/b2)×b′×N}
(4) As a result, the above expression (1) for calculating the forward inclination angle α is satisfied as follows:
α=sin−1(ΔL/a)
=sin−1{(1/b1−1/b2)×b′/a′×N}
As described above, according to the present embodiment, the forward inclination angle α and angle β can thus be calculated, so that the downward inclination angle r can be calculated according to the following expression:
r=β−α
The inward inclination angles p and q of the left and right loupes can be calculated as follows. In
The computer 23 can calculate the distances XR and XL from the coordinates of the above-mentioned respective left and light pupil center positions. Thus, the inward inclination angles p and q of the left and right loupes are as follows:
p=tan−1(M/XR)
q=tan−1(M/XL)
Then, the attachment positions of the left and right loupes to the carrier lens 4 are determined. As described below, the attachment positions of the left and right loupes are determined by calculating the left and right pupil center positions on the measurement assisting plate 26. The left and right pupil center positions on the measurement assisting plate 26 are calculated by the computer 23 applying arithmetic processing to the first image obtained by the first photographing and second image obtained by the second photographing.
As described above in relation to the conventional techniques, a human's face is not symmetrical, so that, actually in many cases, as illustrated, the frame 25 is somewhat inclined to the left or right even when the left and right eyes are the same in height (i.e., horizontally positioned). Thus, in the present embodiment, on the assumption that the left and right eyes are horizontally positioned and that the frame 25 is inclined to the left or right, the computer 23 processes the image data to calculate the left and right pupil centers QNL1 and QNR1. The same approach is taken in the following processing for the second image obtained by the second photographing.
Even if both eyes of the user are actually horizontal to each other, the left and right pupil centers QNL1 and QNR1 on the image may not be the same in height depending on the set-up state of the camera 22 at photographing. In such a case, in the present embodiment, the image displayed on the screen of the computer 23 is rotated in a plane to perform correction so that the left and right pupil centers QNL1 and QNR1 become the same in height, followed by processing of the resultant image data. Also in this case, the same approach is taken in the following processing for the second image obtained by the second photographing.
In
In
A1=(UA1,VA1)
B1=(UB1,VB1)
C1=(UC1,VC1)
D1=(UD1,VD1)
QNL1=(UQNL1,VQNL1)
QNR1=(UQNR1,VQNR)
Further, on the image of
M1=(UM1,VM1)
MT1=(UMT1,VMT1)
MB1=(UMB1,VMB1)
Here, the measurement assisting plate 26 before being projected on the plane image of
Thus, in the present embodiment, the relationship between the coordinate positions of the respective four vertexes A1, B1, C1, and D1 of the trapezoidal measurement assisting plate 26 recognized on the plane image of
The second image is obtained by photographing the frame from right in front, so that the measurement assisting plate 26 illustrated in
The computer 23 recognizes four vertexes A2, B2, C2, and D2 of the measurement assisting plate 26 and left and right pupil centers QFL and QFR and determines the coordinate positions thereof, respectively, in the u2V2 coordinate system according to the scale for the u2v2 coordinate system set on the screen as follows:
A2=(UA2,VA2)
B2=(UB2,VB2)
C2=(UC2,VC2)
D2=(UD2,VD2)
QFL=(UQFL,VQFL)
QFR=(UQFR,VQFR)
The coordinate positions of the respective vertexes A2, B2, C2, and D2 and coordinate positions of the left and right pupil centers QFL and QFR in the x2y2 coordinate system are represented as follows:
A2=(XA2,YA2)
B2=(XB2,YB2)
C2=(XC2,YC2)
D2=(XD2,YD2)
QFL=(XQFL,YQFL)
QFR=(XQFR,YQFR)
The above coordinate positions in the x2y2 coordinate system are calculated by the computer 23 applying coordinate conversion to the coordinate positions in the u2v2 coordinate system using, e.g., the following determinant. The angle ϕ2 in the following Numeral 1 is the angle of rotation from the u2v2 coordinates to x2y2 coordinates.
Thus, when the vertex A2 is set as a reference point, the positions of the left and right pupil centers QFL and QFR in a far vision state are calculated as follows:
QFL=(XQFL−XA2,YQFL−YA2)
QFR=(XQFR−XA2,YQFR−YA2)
For example, the length of the upper side (lower side) of the measurement assisting plate 26 on the image of FIG. is calculated from the coordinate positions of the respective vertexes A2 and B2. Since the length of the upper side of the actual measurement assisting plate 26 is previously known, the scaled size of the measurement assisting plate 26 in
The following describes how to convert the coordinate positions of the respective left and right pupil centers QNL1 and QNR1 on the trapezoidal measurement assisting plate 26 in
In one embodiment, it is assumed that the actual rectangular measurement assisting plate 26″ is rotated, with the bipupillar line (HR1-HL1) as a rotation center axis, to a plane corresponding to the trapezoidal measurement assisting plate 26 by the downward inclination angle r in the direction opposite to the above such that the upper and lower sides thereof are directed forward and rearward, respectively. In
Then, the computer 23 determines a length h1a between the two points Mt1 and M1 on the vertical line Lv and a length h1b between the two points M1 and Mb1 thereon according to the scale on the screen and calculates the ratio of the lengths (h1a:h1b=m). Further, assuming that two points at which the vertical line Lv crosses the upper and lower sides of the virtual rectangular measurement assisting plate 26″ are Mt12 and Mb12, the ratio of the lengths (h12a and h12b) between the two points (Mt12 and Mb12) and midpoint M1 is m, which is the same as the ratio of h1a:h1b.
The length h12 between the two points Mt12 and Mb12 can be calculated from the scaled size of the measurement assisting plate 26″ of
Thus, the coordinate positions of the respective points Mt1 and Mb1 on the upper and lower sides of the measurement assisting plate 26″ of
The coordinate positions of the respective A1, B1, C1, and D1 in the x1y1 coordinate system can be easily calculated from the coordinate positions of the respective Mt1, Mb1, and M1 after coordinate conversion. Thus, for example, when the vertex A1 is set as a reference point, the positions of the left and right pupil centers QNL1 and QNR1 on the measurement assisting plate 26″ in a near vision state are calculated as follows:
QNL1=(XQFL−XA1,YQFL−YA1)
QNR1=(XQFR−XA1,YQFR−YA1)
Further, since the scaled size of the measurement assisting plate 26″ of
In another embodiment, the actual rectangular measurement assisting plate 26 before being projected in a trapezoidal shape on the plane image of
This coordinate conversion is executed as follows. First, from the photographed image of
The coordinate positions of the respective four vertexes A1, B1, C1, and D1 of the measurement assisting plate 26 when the actual measurement assisting plate 26 is viewed as a rectangle from right in front are previously known from the actual dimension of the trapezoidal measurement assisting plate 26. Thus, in a so-called pinhole camera model, a conversion matrix T that converts the rectangular image of the measurement assisting plate 26 facing forward into the trapezoidal image of
For example, “findHomography function” is known as such a known function. The following Numeral 3 is represented using the findHomography function. This is a relational expression between coordinates (u1, v1) on the first image plane and coordinates (u′, v′) on the plane including the measurement assisting plate 26″ in the three-dimensional coordinate system before projection on the first image plane.
Of course, according to the present invention, various functions other than the findHomography function or calculation expressions can be employed as long as the perspective projection conversion of projecting three-dimensional coordinate points on an image plane is performed.
According to still another embodiment, based on the thus calculated coordinate positions of the respective vertexes of the rectangular measurement assisting plate 26″ and coordinate positions of the respective vertexes of the trapezoidal measurement assisting plate 26, the angle of rotation about the bipupillar line (HR1-HL1) between a plane including the measurement assisting plate 26″ and a plane including the trapezoidal measurement assisting plate in
The following relational expression of Numeral 4 is satisfied between the coordinates (u′ and v′) of the plane including the measurement assisting plate 26″ in
Thus, the angle r can be obtained by calculating sin r or cos r in the Numeral 4 from the coordinate positions of the respective vertexes of the measurement assisting plate 26″ and coordinate positions of the respective vertexes of the trapezoidal measurement assisting plate 26.
In step S6, for example, an NC working machine is used to form the loupe attachment hole in the carrier lens 4. The NC working machine previously stores a loupe attachment hole processing program. The downward inclination angle r, inward inclination angles p and q, and loupe attachment position on the carrier lens determined in Steps S4 and S5 are input to the NC working machine, and the frame 25 is set at a predetermined position. Then, the carrier lens 4 is automatically processed to thereby form the loupe attachment hole at a desired position and in a desired direction with accuracy.
In Step S7, the left and right loupes can be fixed to the corresponding carrier lenses using the attachment part (
The loupe 5 is inserted into the through hole of the attachment adapter 11 with its rear end portion (eyepiece side) facing the front side of the carrier lens 4, and the loupe fixing ring 12 inserted from the back side of the carrier lens 4 is screwed to a threaded part of the outer periphery of the rear end portion of the loupe 5, whereby the loupe 5 is fixed to the carrier lens 4. At this time, the loupe fixing ring 12 is fastened to the loupe 5 while making adjustment such that the optical axis of each loupe matches the downward inclination angle r and inward inclination angles p or q, whereby the loupe 5 can be fixed with higher accuracy to a desired position of the carrier lens 4 at a desired angle. For example, a laser positioner or other known positioning means can be used for the optical axis adjustment of the loupe 5.
In another embodiment, the loupe 5 adjusted in terms of the downward inclination angle r and inward inclination angles p or q can be fixed directly or through the attachment adapter 11 to the loupe attachment hole 10 with an adhesive. Other various known means can be used for fixing the loupe 5 to the carrier lens 4 while adjusting the attachment position and direction.
The present invention can be applied not only to the lens fitting type described in the above embodiment, but also to the binocular loupe devices of other types or those having other structures, such as the front hanging type using a clip or an arm and the headband type described in relation to the conventional techniques. In the case of the front hanging type or headband type, the measurement assisting plate 26 is disposed at a position corresponding to an arm or the like that holds the loupe in such a direction that the plane of the measurement assisting plate is orthogonal to the front view direction of the user. As a result, as in the above embodiment, by processing the image data captured by the camera 22 of the loupe attachment position determination system 21 in the computer 23, it is possible to determine the downward inclination angle r and inward inclination angles p and q and thus to determine the loupe attachment position. In this case, the pupil position on the measurement assisting plate 26 determined by the present invention corresponds to the actual loupe attachment position.
While the present invention has been described in detail in connection to the preferred embodiment thereof, it should be understood that the present invention is not limited to the above embodiment but various alternations or modifications may be made within the technical scope of the invention. For example, when the user who ordinarily uses vision correction glasses wears the binocular loupe device on the vision correction glasses (lenses), a planolens (vanity lens) is used as the carrier lens 4. When the user wears the binocular loupe device without the vision correction glasses, a prescription lens can be used as the carrier lens 4. In this case, a far vision position of the prescription lens can be set according to the pupil positions QFL and QFR measured using the second image captured in step S5.
| Number | Name | Date | Kind |
|---|---|---|---|
| 3273456 | Feinbloom | Sep 1966 | A |
| 20140109918 | Nabai | Apr 2014 | A1 |
| Number | Date | Country |
|---|---|---|
| 2003-204972 | Jul 2003 | JP |
| 2005-257802 | Sep 2005 | JP |
| 2014-044391 | Mar 2014 | JP |
| 2007057987 | May 2007 | WO |
| Entry |
|---|
| https://web.archive.org/web/20160525172356/http://optikam.com:80/products/optikampad/measurements/ May 25, 2016. |
| Number | Date | Country | |
|---|---|---|---|
| 20180348542 A1 | Dec 2018 | US |
