JPS5985642A - Self-conscious refractive index measuring apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

The present invention relates to a subjective refractometer. Conventionally, with subjective refractive power measurement devices, for example, optotypes for refractive power testing are placed individually in front of the examinee's eyes, and the refractive power is adjusted to the fundus of the eye through a corrective optical system that allows adjustment of the refractive power. After receiving the test subject's response, the corrective optical system is adjusted until the target appears properly to the test subject to obtain the corrected value, and the refractive power of the subject is measured based on this corrected value. It is known that it is composed of In addition, the image of the corrective optical system is formed in front of the subject's eyes via a relay optical system without placing the corrective optical system in front of the subject's eyes, so that the image of the corrective optical system can be formed in front of the subject's eyes without being confused by the optical system in front of the subject. Devices that accurately measure the refraction of a subject under natural vision conditions are also known. By the way, in this type of device, the refractive power of both eyes of the subject must be measured independently, and the refractive power test optotype and projection optical system are provided separately and each refractive power test is performed separately. The light beams from the optotypes are projected onto the fundus of both eyes of the subject using respective projection optical systems. However, when two separate projection optical systems are provided in this way, the two light beams projected onto both eyes of the subject are parallel to each other when the distance refraction m11 is constant, and the binocular visual axes of the subject are However, even if the refractive power test optotype is moved along the optical axis of each projection lens system during near refraction measurement, the two light beams projected onto both eyes of the subject are parallel to each other. The subject's binocular visual axes will not be in the actual near vision state. By the way, when measuring near refraction, the visual axes of both eyes of the subject are crossed on the target image for refractive power test to create a state of natural near vision, that is, an appropriate convergence state, and then the refractive power is measured. Unless this is done, highly accurate measurements cannot be made. Therefore,
In the conventional apparatus, when the near refraction 41 is in regular use, a deflection prism for colliding is inserted into the optical system to perform appropriate visual axis conversion. However, with this conventional device, when measuring near refraction, it is necessary to insert a special declination prism, and it is also necessary to change the amount of prism declination depending on the near distance. However, it also had some drawbacks in terms of measurement work efficiency. In addition, this declination prism 11
If you place it in front of your eyes, this declination prism will cause confusion.
1) It had the disadvantage that measurements could not be taken under natural vision conditions, and that the effects of the device, which was configured to perform measurements without a corrective optical system placed in front of the eyes, could not be utilized when measuring near refraction. be. The present invention was made in order to solve the problems of the conventional device, and it is possible to perform binocular visual axis conversion operation extremely easily not only in continuous refraction measurement but also in near vision refraction measurement. An object of the present invention is to provide a subjective refractive power measuring device that allows a subject to measure refractive power in a state of natural vision. Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG.
, :: a measuring optical system S for measuring the refractive power of the measuring optical system S, and an index projection system H for projecting an index for setting the positional relationship of the eyes E1, E, 2 to be examined onto the eyes E1, E4 to be examined. And the eye to be examined E1, j,! , and a sighting system J for aiming at the target. Note that the suffix 1°2 attached to the reference numerals hereinafter refers to the right eye and the left eye, respectively, except for the explanation of the arrangement spacing of the optical system shown in FIGS. 2 and 3. First, to explain the measurement optical system S in detail, the light from the light source (2) illuminates an optotype 4 for refractive power test provided on a rotating P1 plate 3 through a condenser lens 2. There are various kinds of sights 14 for detecting spherical power, cylindrical power, cylindrical axis, etc., and these are selected by rotation of the rotating disk 3 and inserted into the optical path. Note that the light source 1, condensing lens 2, and rotating disk 3 are movable along the optical axis for near refraction measurement, which will be described later. The light beam from the optotype 4 is transmitted via a first projection lens 5 to a pair of correction optics provided behind this lens 5 for correcting spherical power, cylindrical dust, cylindrical axis, etc. Pass through 2. The corrective optical systems Kx, 2 are arranged at symmetrical positions on both sides of the optical axis of the first projection lens 5, and have the same optical configuration. Below, the corrective optical system I <> for right eye measurement will be taken as an example and the corrective optical system 1. To explain the details of 2, the corrective optical system 1 includes a first group lens system 61, a second group lens system 71, a third group lens system 8] first and second cylindrical lenses 91, 91, and a deflection prism. io1.1(1+, 111, ILl), and can correct the spherical power by moving the first group lens system 61 along the optical axis.Here, the third group lens system 81 is 2 The first and second cylindrical lenses 91 are sandwiched between these two lens systems.
．． 91, the cylindrical bottom can be corrected. These two cylindrical lenses 91 and 91 are cylindrical lenses with the same absolute value of the cylinder base and opposite signs, and are rotatable around the optical axis, and both lenses 9+, 9
Rotating the + in the same direction by the same angle corrects the cylindrical axis, and rotating in opposite directions by the same angle corrects the cylindrical power. On the other hand, the 381st
'Two deflection angle prisms A placed behind the lens system 81
lOx and IOt have angles of deviation that are symmetrical with respect to the vertical axis perpendicular to the optical axis, and these angle prisms 10z and lol
By rotating the lenses around the optical axis in opposite directions and at the same angle, the horizontal prism value of the eye E1 to be examined is corrected. In addition, the declination prism], Or, the declination prism 11], which is arranged behind the declination prism 101, and the declination prism 1
The structure is optically rotated by 90° with respect to 01.101, and the vertical prism 11° value of the eye E1 to be examined is obtained by rotation in the same direction and angle as above. In this way, the right eye z1 path correction optical system 1 is configured to independently correct and obtain refractive conditions such as spherical power, cylindrical base, cylindrical axis, and prism value.
The corrective optical system K2 for left eye measurement can be explained in the same way, so the details will be omitted. In addition, for each corrective optical system Kz, =+ indicates the eye to be examined E1. In order to match the interpupillary distance of Ear, it is movable in parallel to the horizontal direction across the optical axis of the first projection lens 5. In this way, 1. The light fluxes that have passed through 2 pass through the second projection lens 12, half mirror 13, third projection lens 14, and half mirror 15, respectively, to the subject's eyes El, E, ! , and passes through the terminal pupil to form an image of the optotype 4 on the fundus of both eyes. In addition, each corrective optical system has 1. The light flux passing through Ky is the second
A relay lens system R consisting of a projection lens 12 and a third projection lens 111 relays the inner eye E1.
．． Image 2 is formed in the corrective optical system Kz at the eyeglass wearing position of E2 (approximately 12 mm from the front of the eyes). Therefore, it is equivalent to 1 and K2 being placed in front of the eyes in the corrective optical system, and the subject can standardize the image of the optotype 4 in a state of natural vision through the half mirror 15. . In this way, the subject responds to the examiner while looking directly at the visual target 4 in a state of natural vision. Kitm will try to correct it,
The refractive power is measured based on the corrected value. Next, the arrangement and light flux state of the 11 constant optical system S will be explained in detail according to the schematic diagrams shown in FIGS. 2(a) and 3(b) and 3(a) and 3(b). In each figure, the same reference numerals refer to the same components as in Figure 1 (U) in each figure, and each lens system is a thin lens whose front principal point position and rear principal point position coincide for the sake of simplicity. It is expressed as Ob. Figures 2 (, >) and (b) show the arrangement of the optical system during distance refraction measurement, and to explain an example of the optical data, the focal length fxL of the first projection lens 5 is 250 m1+,
Focal length of the second projection lens 12 KG r =], 50
own. The focal length fi of the third projection lens 14 is the second projection lens 1
Same as that of 2, it is 150 to. Further, the distance Q between the optotype 4 and the first projection lens 5, 1 is 250+twu
, the distance Q between the first projection lens 5 and the corrective optical system +, 2
2 is 250+nm, and 1. To:! The distance Q3 between the second projection lens 12 and the second projection lens 12 is 100 uuu, and the distance Q and I between the second projection lens 12 and the third projection lens 14 are 3
00nmn. Furthermore, the third projection lens E and the eyeglasses wearing position P1 of the subject's eye E1, E::. P: Interval Q with +
,! , l 200 mu, corneal position of the eye to be examined M1. M:
: and eyeglass device position P1. The distance Q6 from P2 is 12 +
+in. Under such optical data, when the corrective optical system Kt is set to a spherical power of 0 diopter, Fig. 2(a)
This will be explained below. The principal rays of the light beams of the optotypes 4 and 11 are reciprocated by the first projection lens 5 while being kept parallel to each other by the correction optical system 'i<1. (<:!I,' - the second projection lens 12 and the third projection lens 14 intersect on the optical axis at a position between 111 and 111, and the third projection lens 14 makes parallel to each other 2-) The ray of light and the 9 subject's eye E1. Reach E2. Further, the image of the optotype 4 is once focused on the dot on the optical axis and then transmitted to the subject's eye E1 via the third projection lens 111. The images are respectively formed at the fundus positions β1 and β−·′2 of Ez. In this case, the subject's spherical power is 0.
Deopter. The center points Yi and Y2 of the corrective optical system I1 and I2 have a conjugate relationship with the points δ1 and δ at the subject's glasses wearing positions P1 and Pz with respect to the second projection lens 12 and the third projection lens 14. It is set as follows. For this setting, positioning adjustment of the measurement optical system S with respect to the subject is performed. This adjustment will be described later. By adjusting the settings, it is possible to create the same condition as if the corrective optical system were placed at the position where the subject wears glasses, even though the corrective optical system is not placed in front of the subject's eyes. Note that the corrective optical system Kx, :: has been explained using a thin lens system in which the front principal point position and the rear principal point position match, but in an actual thick lens system, The principal point position is 11p when the subject is wearing glasses.
1 and P4 points δ1 and δco are set to be conjugate. Next, to explain Fig. 2 () J): - This is due to 1. 2(a) shows the state of the light flux when the spherical power of 2 is set to 110 diopters, and the other optical arrangement, position of the subject, etc. are the same as in FIG. 2(a). Here, 1. 2 is constructed so that the position of the rear principal point does not change even if the spherical power is changed, and the conjugate relationships between points γ1 and δJ, and points γ and δ are the same as in Figure 2 (aC). .The image of the optotype 4 is the eyeglass-wearing position P of the subject.
1. After being imaged at points EJ and E knee 100+n+n ahead of Pl, the images are projected onto the subject having a spherical power of −IQ diopter and are imaged at the fundus positions β1 and β2. Distance refraction measurement is performed in this way, but as mentioned above, the principal rays of the two beams projected onto both eyes of the examinee are always kept parallel, and the refraction measurement is performed while the examinee has natural distance vision. I can finish it. Next, the optical arrangement and the state of the light flux during near refraction measurement will be explained based on FIGS. 3(a) and 3(b). When measuring near refraction, the optotype 4 is moved along the optical axis toward the first projection lens 5 together with the source 11) and the condenser lens 2, and for example, 300 own near refraction measurement is performed. In this case, the distance Q1 between the optotype 4 and the first projection lens 5 is 41, G
Move settings are made to nun. Other optical arrangements,
The position of the subject, etc. is the same as in the case of distance refraction measurement. In Fig. 3(a), the corrective optical system is 1, K: l! FIG. 3(b) shows the luminous flux state when set to 0 dayopter and when set to -10 dayopter. First, referring to FIG. 3(a), the two principal rays of the luminous flux from +m4 intersect at the second point φ of the optical axis between the second projection lens 12 and the third projection lens 14, and then cross at the third point φ. It reaches the subject through the projection lens 14 at an intersection angle, that is, a width comparison angle O. Note that the image of the optotype 4 is formed at a point φ on the optical axis −L. Further, a point ω in front of the point φ on the optical axis is the virtual image position formed by the third projection lens 14, and this point ω is set at 300 + nm in front of the subject's glasses-wearing position [Pl, P:. Ru. As a result, the subject is in the glasses wearing position Rz-P,
In front of :1lOO111111, the near natural hμ state full? It can be based on the standard. FIG. 3(b) shows the case where the corrective optical system K', [<z is set to −lO diopter, and the image of the optotype 4 is located at the glasses-wearing position Pz of the subject whose spherical power is 110 diopters,
P is tied at point 11, t2 of 75 nun in front of this. In this case as well, the eye to be examined E1. The angle formed by the principal rays of the two luminous fluxes reaching E:4, that is, the cross-sectional angle θ, is shown in Figure 3 (
This is the same as in case a), and the subject can standardize the optotype 4 in a proper width comparison state, that is, in a near natural vision state. In addition, in this example, the near refraction measurement distance is: 'l
Although set to OOnnn, near refraction measurement can be performed at a desired distance by changing the amount of movement of the optotype 4, and an appropriate convergence state can be created at any measurement distance. In this way, when performing near refraction measurement, it is possible to obtain a standard by simply moving the visual target 4 along the optical axis11, and this standard is used for near natural vision. This can be achieved under the following conditions. In addition, in this embodiment, the correction optical system Kx,
The position of: (corresponds to the front principal point position when assumed as an internal lens system) is located at the front 250 of the first projection lens 5.
It is located on mn+. As a result, when the optotype 4 on the rotating disk 3 is referenced? The viewing angle is not affected by the position of the optotype. This eliminates the need to select optotypes of different sizes by rotating the rotary disk 3 depending on the measurement distance, thereby improving measurement efficiency. Note that similar effects can be obtained even if the first to third projection lenses in this embodiment are configured with concave mirrors. Next, a subject eye position setting optical system l for setting the subject's eyes Ei, , E:r, to appropriate positions will be described. The subject 111+position setting optical system (2) includes an instantaneous index projection system H for projecting the elevation of the index 18a1, 18b1 toward the subject's eyes E1, E. It is composed of one aiming optical system J for illuminating the anterior ocular segments of both eyes of E, :j:j,+5. First, the index projection system 1 (for example, the right eye projection system is the first
This will be explained with reference to FIGS. 1 and 5. The light from the light source 161 illuminates the index plate 181 for detecting the working distance through the aperture lens 1.71. This index plate 181 has index marks 18 on the front and back sides, respectively, as shown in FIG.
a*, 18bz are provided. And these indicators 18a1. ], 8b+ images are formed on the anterior segment of the subject's eye Ez via the fourth projection lens 191 and the reflecting mirror 201. Furthermore, indicator 18
az is the working distance (measuring optical system S and eye E

The index 18b1 is used to set the working distance in the case of contact lenses. Further, the filter 211 provided in front of the light source 161 transmits light in the near-infrared band, and has the effect of preventing miosis during measurement of the subject. Since the left eye projection system has a similar configuration, its explanation will be omitted. As will be described later, the optical axis of these J-Fi standard projection systems I is inclined with respect to the optical axes of the measurement optical system S and the aiming optical system J. In addition, a virtual line Va passing through the center of the fourth projection lens 191 and orthogonal to its tip axis and the measurement optical system S
When the point where the optical axis of the measuring optical system S intersects with the virtual line vb connecting the centers of the two indices 18at, 18bl of the index plate 18 and the optical axis of the measuring optical system S coincides with the point where the optical axis of the measuring optical system S differs by .degree., the index 18ax, The optimum state of the 18bx focus can be obtained, and the image of the index 18a1 or 18b1 at Ml or Ql, which will be described later, can be clearly observed and measured. This minus number of points is point F1 shown in FIG. The principle of setting the working distance using the index projection system 1-1 will be explained below with reference to FIG. Note that unless otherwise specified, only the right eye projection system will be described. Point Q1 is a position that is conjugate with the rear principal point position of corrective optical system 1 in measurement optical system S, and when measuring the subject's corrective refractive power for normal glasses, the position of point Q1 is It is necessary to set the working distance so as to match the glasses wearing position P1. Therefore,
When the eye E1 to be examined is positioned as shown in 1-2, an image of the index 18a1 is formed at the corneal apex M1 of the eye E1 to be examined. Therefore: The examiner aims at the anterior segment of the subject's eye using the sighting system j and sets the working distance so that the image of the index 18a1 coincides with the center of the pupil. Next, a case will be described in which the positive refractive power of the eye to be examined for contact lens 1 is measured. In this case, the point at which the corrective optical system K1 forms an image, the position of the QD,
It is necessary to match the anterior segment of 1. Therefore, the index 18b1 is such that when the eye E1 to be examined is aligned with the position of the point Q1, the image of the index 181]j is formed at the center of the anterior segment of the eye to be examined. Therefore, when measuring the corrective refractive power for contact lenses 1 to 1, the examiner should:
The anterior segment of the subject's eye is sighted by the sighting system J, and the working distance is set so that the image of the index 18b1 coincides with the center 1167. Note that the indexes 18a1 and 18b1 are carved on the projection lens 191 and placed at the finger 1=a, + so that the focal position is shifted, and when set to a predetermined working distance, the eye to be examined E1
The image can be focused on the anterior segment of the eye. Next, the aiming optical system J will be explained. As shown in FIG. 1, the subject's eye E1. IE The light flux from both anterior segments of the eye passes through the half mirror 15 and the third projection lens 4 to the half mirror.
13 and sighting plate 23 by Itoko (gt Reren 22)
a, reached 23b and reached this light) 41! Provisional 23a, 2
3+) Both anterior segment images of the subject's eyes Ez and E:: are formed on the image. Since the third projection lens 14 and the imaging lens 22 have a telecentric optical system, the sights 123a, 23
The anterior ocular segment images of the eyes Ex and E2 to be examined on b can be observed without causing position error even if the working distance is not appropriate. The aiming plates 23a and 23b are shown in FIGS. 6 and 7.
As shown in the figure, each of them has aiming indicators na, nb, and rlc, which are arranged with the respective indicator forming surfaces facing each other with a minute interval therebetween, and the corrective optical system in the measuring optical system S has 1. It is possible to move relatively in conjunction with the movement of the distance between the optical axes in step 2. In this way, the subject's eye E1. The images of both anterior eye segments of E+ are superimposed on the images of indices na, nb, and nc, and these images enter an image pickup tube 26 via a mirror 24 and a relay lens 25 and are converted into video signals, which are then displayed by a monitor television 27. Observation becomes possible. The procedure for setting the position of the eye E1.
This is a schematic representation of the image displayed in the image Δ1.
A2 is the eye to be examined E1. An image of the pupil of E=, the image Ba1.
3az is the target eye E1. This is an image of the finger 4'1L8a1.18a2 projected onto E, :. Note that images of the indicators 18b1 and 18b2 are omitted from illustration. Also,
The image height and the holes are indicators na and nb formed on the sight plate 23a.
The crystal is an image of the index nc formed on the aiming plate 23b. In the case of Fig. 8 (a゛), the corrective optical system Kx, K
In addition to the fact that the distance between the optical axes of No. 2 does not match the interpupillary distance of the subject, and the central optical axis of the measurement optical system S does not match the center of the subject's eyes, System S and test eye E1,
This indicates that the distance between E2 and the working distance is not appropriate. The adjustment procedure for transitioning from such an inappropriate setting state to a proper setting state will be described below. First, the eye to be examined E1. E:! The refractometer body or the subject itself is adjusted by moving downward one step so that the pupil image A1, A, = is sandwiched in the center of the index image height. At this time, the subject is fixed to a subject holding section (not shown), and the position of the subject can be adjusted by moving this subject holding section. This adjustment completes the optical axis alignment in the vertical direction (see FIG. 8(b)). Next, as shown in FIG. 8(C), the index image B a 1.
, Ba2 is located at the center of the index image na, that is, the apparatus body or the subject itself is moved along the measurement optical axis so that it coincides with the center of the pupil images Al and A2. This movement adjustment completes the setting of the working distance. Next, as shown in FIG. 8(d), the pupil image A1 and the index image n
The apparatus main body or the subject is moved in the left-right direction so as to equalize the distance between the pupil image A2 and the index image height. With this adjustment, the central optical axis of the measurement optical system S and the eye to be examined E1. Optical axis alignment in the left-right direction of the center of E;: is completed. Next, as shown in FIG. 8(e), the aiming plate 23a. 231), the index images a and i are moved and adjusted in the left-right direction, and the pupil images A1. Recite the index image and align the sieve with the center of A2. In addition, the sight plate 23a, 231+l ma-1-
As described above, the aiming plates 23a and 23b move by equal amounts in opposite directions, and the movement of the aiming plates 23a and 23b is caused by the correction optical system t.
(1, K';:) is linked to the movement of the optical axes of the corrective optical systems Kl and K2.
The optical axis of the measurement optical system S can be made to match the interpupillary distance of eye E2. Align the optical axis of E2. and working distance adjustment is completed. Next, corrective optical system Kx, 2! No. 9 regarding the drive mechanism
This will be explained based on the diagram. In the correction optical system, 1 and K-2 are attached to optical benches 301 and 302, and are movable within a plane including both optical axes so as to bring the two optical axes closer together or farther apart. That is, the optical benches 30 Motor 36 for movement via
is connected to. Here, the male threaded portion 3 of the connecting member 33
4 is divided into two halves with opposite threads, each of which is adapted to be screwed into a female threaded portion of the bracket 32 of the optical bench 30t, 302. Note that the screwing state of the bracket of the optical bench 30 and the connecting member 33 is m3L, which is not shown in the figure. Next, lens driving of the corrective optical system Kx, ni:: will be explained, but since both optical systems have the same configurations 8 and 8, the description will be made using 1 for one optical system as an example. The first group lens system 61 is arranged at the front end of the lens barrel 371 and
1 is attached with a rack 381 extending in the optical axis direction. This rack 381 is engaged with a pinion 391, and this pinion 391 is pivotally supported by the motor 40. This allows the first group lens system 61 to move along the optical axis. Further, a second group lens system 7 is provided behind the first group lens system 61.
One of the first and third group lens systems 81 is arranged at a predetermined interval, and each lens system 71.81 is fixed to the optical bench 301. Furthermore, a lens barrel 411 is located behind the lens barrel 37J.
is provided, and this lens barrel 411 has two cylindrical lenses 91
．． 91 are arranged one behind the other. One cylindrical lens 91 is engaged with a ring gear 421, and this ring gear 421 is connected to the motor 44 via a drive gear 431. Further, the other cylindrical lens 101 is attached to a ring gear 45 provided behind the ring gear 421, and this ring gear 451 is connected to a motor 471 via a drive gear 461.
7 and 58 are attached to stabilize the horizontal movement of the optical benches 301 and 302. In addition, the optical bench 301
, 302 is connected to a slide plate 62 via guide rods 59z, 592 and arms 60z, 602.
1°622 are connected, and arms 60t, 60. : is freely rotatable around the rotation pins 611 and 6'12, and the slide plates 621 and 622 can be moved. 1 in the corrective optical system depending on the amount of II. 2, the amount of horizontal movement of the optical axis can be viewed through the mouth. The correction optical system configured in this way has 1. 2 is each motor 36.4 (lh, /+02 ・
Adjustment drive is performed by controlling the old... by the output of a control calculation circuit which will be described later. In addition, optical bench 3o-!
Motors 44z and 47x, which were investigated in 2015, are not shown in the illustration and have the same function as the motors 44z and 47x.
Illustrations and descriptions of members and parts that appear symmetrically in K2- are omitted. Next, a processing system such as a control arithmetic circuit for controlling and driving the present device will be explained based on FIG. In the figure, reference numeral 70 denotes a control calculation circuit, and this control calculation circuit 70 performs control calculations to operate the drive output part Y and the display means Z upon receiving signals from the drive input section Xa or the data input section Xb. It is composed of a microcomputer, etc. The data input section xb is for inputting the refractive power data of the subject's eye that is roughly known in advance, such as measurement result data with an objective refractometer. Input il! The subjective refractometer of the present invention can accurately measure the fovea in a short time based on the correction power set based on the fixed result data. The distance/near changeover switch 71 of the drive input section Xa is connected to a motor 73 for moving the refractive power test optotype 4 via a drive circuit 72.
The drive signal is supplied to the control calculation circuit 70 to provide selection information for distance refraction measurement or near refraction measurement. In addition, the correction optical system inter-axis movement switch 7 of the drive input section Xa
4 gives driving information to the moving motor 3G for changing the distance between the respective optical axes of the correction optical system Kj, . The moving motor 36 is driven through a drive circuit 75 that constitutes the drive output section Y. Furthermore, the movement motor 3 is activated by the operation of the correction optical system inter-axis movement switch 74.
6 is driven and the aiming plates 23a and 23b move to determine the interpupillary distance, and the value is displayed on the interpupillary distance display section 76 constituting the display means Z. Incidentally, the interpupillary distance is also controlled by a command from the pupillary distance data section 77 constituting the data input section xb. In addition, [spherical power change switch 71h of dynamic input section Xa,
, 7B2 provides drive information to the movement motors 40x and 402 of the first group lens system GI1.6:E, and provides drive information to the control calculation circuit 70 and the drive circuit 7 of the drive output section Y.
A drive signal is given to the motor 401, /IQ: through this. In this way, when the spherical power Sp changes, a corresponding value is displayed on the spherical power display section 80 of the display means Z. Note that the spherical power Sp is also controlled by a signal from the spherical power data section 81 of the data input section xb. Further, the cylindrical power variable f-hi switch 82 of the drive input section xb
1-. 822 are first and second cylindrical lenses 91, 9.
2.91.9. : It provides drive information to the motors /lh, 471 that aim to rotate in mutually opposite directions, and the control calculation circuit 70 and the drive circuits 831, il of the drive output section Y
l:, 8:h, motor 4/11. through 832.
The drive signal can be sent to 411. When the cylinder power Cp changes in this way, the value is displayed on the cylinder power display section 84 of the display means Z accordingly. Further, the cylinder power Cp is also controlled by a signal from the cylinder power data section 85 of the data input section xb. Further, a cylinder axis angle change switch 851 of the drive input section Xa,
85. :: is the first and second cylindrical lens 91.9, ::
:, 9:t, 9S motor 44 for rotating in the same direction
1', '17j, and provides drive information to the control calculation circuit 70 and the drive circuits 831 and 83 of the drive output section Y.
;shi, 831.8:32 via motor/I/h;
A drive signal is given to 471. When the angle of the cylinder axis is determined in this way, the value is displayed on the cylinder axis angle display section 86 of the display means Z. Further, the angle of the cylinder axis is also controlled by a signal from the cylinder axis angle data section 87 of the data input sections x and b. The horizontal deflection prism change switches 81h and 88 of the drive input section Xa are horizontal deflection prism l.
Oz, 101. Tff2. ], 0=4 It supplies drive information to the motor 5:'i, 522, which aims at rotation of 0=4, and the control calculation circuit 70 and the drive output section YT7)
Motors 52i, 52 via drive circuits 891,892
A drive signal is given to this. Also, a vertical deflection prism change switch for the drive input section Xa! 10t
, 902 are vertical deflection prisms li1. lit
, 112. A motor 561 for rotating 112, 5
It provides drive information to the control arithmetic circuit and the drive circuit 91'l of the 15F dynamic output section Y, 91. ::
A drive signal is given to the motors 5G+, 56; In this way, the deflection prism 101.
10t, lit, L', 1, . Further, the prism value is also controlled by the skew correction prism value data section 93 (by No. 8) of the data input section xb. Incidentally, signals corresponding to the values displayed on the name display sections 76, 80, . . . of the display means 2 are obtained from the image pickup tube 26.
Synthesizing port 1 that constitutes the signal processing section 94 together with the image signal
&95 performs signal synthesis, and in response to the output of this synthesis circuit 95, the results of the refractive power measurement to be corrected on both sides of the monitor television 27 are displayed. Next, a control example of the control calculation circuit 70 will be explained. For example, by operating the spherical power change switch 781 or the cylindrical power change switch FB21, the desired spherical power SQj2;
In order to obtain a cylindrical power of C8, correction) lG system K
l first group, second group and third group lens system 61.71.
81 (hereinafter referred to as spherical optical system) - first and second cylindrical lenses 91.91. (hereinafter referred to as a cylindrical optical system) can be adjusted as follows to obtain a good bλ. In other words, the combined refractive power of the spherical optical system and the cylindrical optical system is the first and second
Since it is expressed as a function of the intersection angle α0 of each axis of the cylindrical lens 91.91, the spherical power S. Or cylinder power C1
] Adjustments are made to set the intersection angle α0 corresponding to . In addition, when obtaining the angle of the cylinder axis, that is, the angle β1 of the strong principal meridian with the cylinder axis change switch 851, the sum of the intersection angle α0 of each axis of the first and second cylindrical lenses 91 and 91 and the reference angle. Alternatively, the first cylindrical lens 9 or the second cylindrical lens 11 may be rotated by an angle determined by the difference. Furthermore, in order to select a desired prism 1-direction PO by the horizontal deflection prism change switch 881, a predetermined relational expression is established between the rotation angle of one deflection prism 101 in the horizontal direction and the prism value Po. Therefore, the deflection prism 101 is rotated by an angle corresponding to the first prism PO. When obtaining the prism value in the vertical direction, it is considered that the horizontal deflection prism 101 is carved and arranged perpendicularly.Similarly to the horizontal direction, the vertical deflection prism 11 is
1. Squeeze to control the rotation. As explained below, according to the present invention, the optotype for refractive power testing is arranged as an optical image in front of both eyes through one projection lens and through two corrective optical systems, respectively. The refractive index is projected onto both eyes of the test subject, and the optotype for refractive power test is set on the optical axis so that it can be moved, making it easy to create an appropriate cross-section condition when measuring near refraction. When measuring the refractive power for near use, the test subject can always take the test with natural vision even at t-9, and the refractive power is exactly i1+! It becomes possible to set I. Furthermore, if the inter-optical axis pressure i1 of each corrective optical system is configured to be variably adjustable, it can always be adjusted to the interpupillary distance of the subject. Furthermore, the lens system for creating an optical image in front of the eye in the corrective optical system is composed of two groups of relay lens systems, the focal length of each lens system is the same, and the distance between each lens system is set to the same focal length. When the size is doubled, the lens becomes optically symmetrical and the utilization rate of the lens is improved. In addition, when the corrective optical system is placed at the back focal position of the projection lens system, the visual angle of the subject using the optotype for refractive power testing as a reference remains constant at the position of the optotype, regardless of the position of the optotype. This eliminates the need to change the visual target depending on the measurement distance, improving measurement efficiency.

[Brief explanation of drawings]

1 to 10 are diagrams explaining the present invention in detail, and FIG. 1 is a perspective view showing the arrangement of the optical system of the subjective refractometer, and FIGS. ) is a schematic diagram showing the luminous flux state of the measuring optical system l-j for distance refraction measurement.
) are diagrams showing the case of −10 days r 71 but, respectively, and FIGS. 3(a) and (1)) are schematic diagrams showing the luminous flux state of the measurement optical system in near refraction measurement. (a)
3(b) is a diagram showing the case of a -10 dayopter, FIG. 4 is a schematic configuration diagram showing the arrangement of the index projection system, and FIG. 5 is a diagram showing the arrangement of the index projection system. Schematic diagrams showing the indicators, Figures 6 and 7, are the fingers of the aiming optical system (
They are schematic diagrams showing the votes, and FIG. 6 shows the index image on one index board, FIG. 7 shows the index image on the other index board, and FIGS. ) is a diagram illustrating the procedure for adjusting the position of the eye to be examined; FIG. 8(a) is the state before adjustment;
1(b) is shown in Fig. 8(b) when vertical adjustment is made.
c) shows the case when the working distance setting has been completed, Fig. 8 (d) shows the case when the left and right adjustments have been completed, Fig. 8 (e) shows the case when all adjustments have been completed, and Fig. 8 (e) shows the case when all adjustments have been completed. The figure is a perspective view showing a lens drive mechanism of the corrective optical system, and FIG. 10 is a block diagram illustrating a circuit for controlling the lens drive mechanism. 4... Optotype for visual acuity test, 5... First projection lens (
Projection optical system), Kx', Kz... Correction optical system, El, lE;>...
Eye to be examined. Fig. 4 Fig. 5 Fig. 61 “1” Fig. 70 Fig. 8

Claims (4)

[Claims] (1) A refractive power test optotype that is movable relative to the eye to be examined;
a group of projection optical systems for projecting the optotype; and a projection optical system arranged behind the projection optical system at a symmetrical position across the optical axis of the projection optical system and configured to be able to change the refractive power. Ta1
A pair of corrective optical systems, and a relay optical system arranged to commonly relay the light flux passing through each corrective optical system and form images of each corrective optical system in front of the eyes of a double-wave optometrist. During distance refraction measurement, the optotype is placed at the front focal point of the projection optical system, and during near vision measurement, the optotype is placed along the optical axis direction of the projection optical system and at the front focal point of the projection optical system. A self-conscious refractive power measurement bag [l'
? . (2) The corrective optical system can adjust the distance between each optical axis within a plane that includes the optical axis of the projection optical system. 6. The subjective refractive power measurement system according to claim 1, characterized in that it is configured as follows. . (3) The relay optical system is composed of two groups of lens systems, and the lens systems of both groups have the same focal length, and the distance between the lens systems of both groups is set to twice the focal length. A subjective refractive power h+susetting device according to claim 1 or 2, characterized in that: (4) Claims 1 to 3, characterized in that the correction optical system is disposed at the rear focal position of the projection optical system.
The subjective refractometer according to any one of the preceding paragraphs.