JP2958012B2 - Eye refractometer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial applications]

The present invention relates to an eye refractometer for objectively measuring an eye refraction of a subject's eye.

[Prior art and its problems]

2. Description of the Related Art In general, various refractometers are known as devices for objectively measuring the degree of refraction of the eye. The refractometer is a device for observing, through an optical system, whether or not a light target is correctly imaged on the fundus of the eye to be examined, that is, on the retina, and objectively measuring the refraction of the eye. For the measurement, as a pre-operation, the positional relationship between the measurement optical system on the apparatus side and the eye to be examined must be adjusted to a measurable state (aimed and focused). As soon as the adjustment is completed, the actual measurement will be started. Conventionally, the measurement start timing is obtained by the measurement person turning on the measurement start switch when the measurement person determines that the adjustment is completed while performing the adjustment, so that the subject moves during the adjustment. In this case, the timing at which the start switch is turned on is often missed or the timing is shifted, and the skill of the measurer has a great influence on proper measurement timing and accurate measurement. Therefore, the time required for the measurement and the measurement result vary considerably depending on the skill of the measurer. Although various types of focus detection mechanisms are well known in optical machines such as cameras, a mechanism for simultaneous detection together with a focus detection mechanism is not known.

[Object of the invention]

The present invention has been made in view of the above-mentioned problems of the prior art, and has been devised to effectively solve the problems. Therefore, an object of the present invention is to automatically start measurement by detecting that the object is both in focus and in aiming, and to perform measurement quickly in a constant condition without missing measurement timing. It is to provide a degree measuring device.

[Means for Solving the Problems]

The eye refractometer according to the present invention is configured as follows to solve the above-described problems of the prior art and to achieve the object. That is, an optical measurement unit having a measurement optical system for objectively measuring the eye refraction with respect to the subject's eye, and calculating the eye refraction by arithmetically processing a measurement data signal from the optical measurement unit. And a main body part. The optical measuring section and the main body section may be separate bodies or may be integrated. The measuring optical system has the following optical systems as one of its components. A measurement light projecting optical system that projects the measurement light or the projection pattern onto the fundus of the eye to be inspected, and a measurement that receives a reflection image of the measurement light or the projection pattern projected onto the fundus of the eye to be examined, for example, on a light receiving sensor The light receiving optical system, the corneal reflection image of the aiming light source, preferably the corneal reflection image or corneal reflection pattern of the aiming light source arranged at a position symmetrical with respect to the optical axis of the measurement light, the light receiving sensor or a separate An aiming and focusing optical system that indicates a relative position between the measurement optical system and the subject's eye by receiving light on a light receiving sensor. Further, the main body section detects that the measurement optical system is focused and focused on the eye to be inspected, starts measurement by the measurement light optical system, and outputs the measurement light from the measurement light reception optical system. Control means is provided for calculating the degree of refraction of the eye based on the image signal.

[Action]

The eye refractometer according to the present invention detects whether or not the aim is in a state of aiming from the position of an image signal on a light receiving sensor based on a corneal reflection image or a corneal reflection pattern of an aiming light source in an aiming focusing optical system. it can. As an example, since the cornea is substantially spherical, the position of the image signal on the light receiving sensor changes depending on the positional relationship between the aiming light source and the subject's eye, and the aim is adjusted by processing this signal position. State can be detected. For example, the center position of the corneal reflection pattern on the light receiving sensor in a state where the aim is aligned is set as a reference position, and in which direction and how much the position of the corneal reflection pattern of the actual aiming light deviates from this reference position. It is possible to calculate from the position of each element on the light receiving sensor, and it is also possible to display the calculated data on some display means. Further, it is also possible to obtain a monitor image from an image signal on the light receiving sensor. Further, in this aiming and focusing optical system, it is possible to determine whether or not the object is in focus. Therefore, it is possible to determine whether or not to start the actual eye refraction measurement based on the data obtained by the arithmetic processing. The determination is made by the control means, and for example, the projection / reception optics of each measurement light A measurement start command signal is output to the system. Since this determination and signal output are always performed instantaneously under constant conditions by the electronic mechanism, measurement timing is not missed and a highly reliable measurement result under constant conditions is obtained.

【effect】

As apparent from the above description, according to the present invention, the following excellent effects are exhibited. In other words, when objectively measuring the eye refraction, the measurement is automatically started by detecting that both the in-focus state and the aiming state are attained. Can be measured.

【Example】

 FIG. 1 shows a preferred embodiment of the present invention.
This will be described with reference to FIG. FIG. 1 shows the flexion of the present embodiment.
FIG. 2 is a block diagram illustrating a schematic configuration of a folding degree measuring device. Illustrated
So that the optical measuring unit 1 and the main unit 2
It is roughly divided. The optical measuring section 1 has a
It has a built-in optical system and is called a handy type.
Large enough to be easily moved with one hand
It is composed of size and weight. Optical measurement
An image signal is input from the fixing unit 1 and one of the contents is
Image recognition device 3 for recognizing aiming and focus matching conditions
The other is a monitor that displays the image signal as an image.
Data 4 are respectively incorporated. Also, the image recognition device 3
While exchanging signals with both
A control signal is output to the optical measurement unit 1 and the image recognition device 3
Based on measurement data obtained from the image signal input to
A control circuit 5 for calculating the degree of eye refraction is also built in. Immediately
That is, the measurement optical system is aimed and focused on the eye to be examined.
, This optical system starts measurement,
Calculating the eye refraction based on the image signal from the measurement unit 1
The control means is controlled by the image recognition device 3 and the control circuit 5.
Will be composed. In the figure, reference numeral 6 denotes the control circuit 5.
The operation switch 7 is a connection switch calculated by the control circuit 5.
This is a printer that prints and outputs the results. Optical measurement unit 1
The main unit 2 is connected by cable (not shown) or wirelessly.
In any case, the test
The position of the optical measurement unit 1 that needs to be adjusted with respect to the eye
Is extracted and moves to the stationary body 2
Is separated as its motor system as in
The patient holds the device and adjusts the position of the eye.
It is extremely simple. FIG. 2 shows a built-in optical measuring unit 1 in this embodiment.
FIG. 3 to FIG. 8 show the measurement optical system 8.
Measuring light projection as each element optical system constituting the fixed optical system 8
Optical system 9, measuring light receiving optical system 10, optotype optical system 11, monitor
Camera optical system 12 and monitor reticle optical system 13
Aiming optical system, and each element of the monitor illumination optical system 14
The optical systems are shown separately. First, FIG. 3 shows the measuring light projecting optical system 9,
An infrared light source is used as the light source 15 for projecting constant light.
Is projected by the first reflection mirror 16 at right angles.
Reflected upward. Of the measuring light reflected upward
Optical axis a₁Above, the right-angle opposite sides of two right-angle prisms are formed
Is the optical axis a₁On the side opposite to the first reflection mirror 16
The first prism 17 joined at an angle of 45 ° is arranged
I have. This first prism 17 is a half prism,
Infrared light is partially reflected at a certain ratio and transmitted through the rest.
And most of the visible light is transmitted. Therefore, the first prism
The optical axis a of the measuring light refracted at right angles by the beam 17_TwoExamining on
By locating the eye E, the measuring light is placed in the eye E to be examined.
Can emit light. The light source 15 and the first reflecting mirror
Optical axis a between 16 and_ThreeAbove, the collimator in order from the light source 15 side
Lens 19, projection pattern mask 20, and projection relay lens 21
Disposed between the first reflecting mirror 16 and the first prism 17
Optical axis a₁An eyepiece 22 is arranged on the top. Measurement light
Is emitted from the light source 15 for projection, and the collimator lens 19,
Projection pattern mask 20, Projection relay lens 21, First reflection mirror
Through the lens 16, the eyepiece 22, the first prism 17, and the corner from the pupil.
After entering the eye E through the membrane surface and the lens, the light is projected onto the retina.
Projects the light marker of the turn. FIG. 4 shows a light receiving optical system 10 for measuring light. Light receiving system measurement
Constant light is obtained from an image of a light target formed on the retina of the eye E to be examined.
Optical axis a of the projection optical system 9 as reflected light_Two, A₁Retrograde along
But reaches the position of the first reflection mirror 16 (shown in FIG. 2).
When the mirror 16 is opened, the first
It passes through the through hole 23. A diaphragm 24 is formed immediately below the first through hole 23.
A second reflection mirror, which will be described later, is located immediately below the diaphragm 24.
25 (shown in FIG. 2), a second through-hole formed approximately in the center
26, the measuring light passing through the first through hole 23 is
Further, the vehicle travels straight through the aperture 24 and the second through hole 26. Follow
Optical axis a₁After passing through the first through-hole 23 of the light receiving system measurement light
Optical axis a_FourGoes straight down as it is and the imaging lens 27 and
The light reaches the light receiving sensor 29 via the filter 28. FIG. 5 shows the monitor illumination optical system 14, in which the monitor illumination optical system 14 is used.
Optical axis a of bright optical system_FiveAround the perimeter of the
In the state, the optical axis a_FiveSix to face the eye to be examined located above
Of infrared light sources are arranged as illumination light sources 30. What
Oh, this optical axis a_FiveIs the optical axis a of the measuring light_TwoMatches. Soshi
Since this illumination is based on infrared rays,
There is no feeling of dazzling. The illumination light from the above-mentioned illumination optical system 14 is emitted from the cornea of the eye E to be examined.
The reflected light is reflected on the eye E of the optical measurement unit 1.
Monitor camera optics as aiming light for aiming
12 is configured as shown in FIG. And this illumination light
Is the light of the illumination optical system as shown in FIGS. 9 and 10.
Axis a_FiveA parallel light beam with an appropriate inclination angle λ
When the light is projected toward the eye E,
Optical axis a of eye E_EIs the optical axis a of the illumination optical system_FiveDeviated from
And six corneal reflections (sighting light) of the six beams
Center position of image (appears to be a reflection image of point light source)
(That is, the optical axis a of the eye E_E) Is the optical axis a of the illumination optical system_FiveAgainst
In principle, the amount of “displacement” occurs.
By measuring ε and setting it to 0, aiming is
I can do it. The corneal reflection luminescent spot of the illumination light source 30 is
More than three times stronger than the
Detection can also be performed. That is, when focused,
Since the point is the smallest and the contrast is strong, this state
May be detected by the image recognition device 3, and the aiming operation may be performed.
Just like the work, pay attention to the same object called the corneal reflection bright spot.
Detection, so both aiming and focusing operations
Can be detected at a relatively high speed, and immediate processing becomes possible. This
The optical axis a of the eye E to be examined_E
Can measure the device side optical axis such as measurement system and monitor system
Can be matched as well as focusing
The distance between the optical measurement unit 1 and the eye E,
Eyepiece 22 of measuring light projecting optical system 9 and corneal surface of eye E to be examined
Can be set to a constant distance suitable for measurement.
Optical axis a of illumination optical system 14_FiveUpper first prism 17 (part of infrared light
Infrared behind (partially transmitted)
A dichroic lamp that reflects lines and transmits visible light
The mirror 31 reflects the aiming light (infrared light) downward at a right angle.
The optical axis a_FiveAre arranged at an angle of 45 ° to
You. This dichroic mirror 31 bends downward at right angles
Optical axis a₆On the top, the characteristics are almost opposite to those of the first prism 17.
Half prism, that is, almost transmits infrared light and transmits visible light
The second prism 32, which is a half prism that reflects most light,
Are located. Reflected by dichroic mirror 31
The aiming light passes through the second prism 32 and remains on the optical axis a.₆To
And goes straight down along the second prism 32.
Via the monitor relay lens 33
Then, the light enters the third reflecting mirror 34. And the aiming light is
Reflected at right angles to the optical axis a₇Along the second reflection mirror 25
Reach. Optical axis a₇Is the measuring light beam on the plane of the second reflecting mirror 25
Optical axis a of academic system 10_FourIntersect with the second through hole 26
Will cross. The aiming light is reflected by the second reflection mirror 25
Reflected downward at right angles to the optical axis a₈Along the light receiving sensor
Reach 29. FIG. 7 shows the reticle optical system 13 for monitoring. 2nd pre
The reticle of the aiming position indicator is displayed on the side of the
Reticle light source 35 and reticle pattern
Mask 36 and reticle objective lens 37 are provided in this order.
Light emitted from the reticle light source 35 has an optical axis a₉Along
By passing through the reticle pattern mask 36
It becomes the sign pattern light, and the reticle objective lens
After passing through 37, it reaches the second prism 32 and is refracted downward at right angles.
It is. The reticle pattern is represented, for example, by a concentric double circle.
The inner circle shows the smallest measurable pupil diameter, and the outer circle shows
It is drawn at a standard position where a corneal reflection image occurs. 2nd prism
Optical axis a of the reticle light refracted perpendicularly downward by 32_Ten
Is the optical axis a of the aiming light₆To match the second prism
There are 32 prism faces. Therefore the light after that
The learning system is the same as that of the monitor camera optical system 12. This
And the optical system of the aiming light after the second prism 32
The optical axis of the illumination optical system a_Five
If the center of the corneal reflected light of the six illumination lights is above,
The center of the heart and the standard pattern of the reticle should match
And the coincidence is detected on one light receiving sensor 29
This means that the aim has been detected. Book
In the embodiment, the reticle pattern is formed by the reticle light source 35 and the reticle.
This pattern is obtained using the tickle pattern mask 36, etc.
The tickle pattern indicates the position on the monitor image that serves as the aiming reference.
Since it is only necessary to be able to display, for example, the pattern
May be written, or monitor camera optics
With respect to the monitor relay lens 33 on the
For example, place a transparent glass plate that transmits infrared light at the position
Then, write a pattern on it and put the pattern on the light receiving sensor 29.
Can be detected. FIG. 8 shows a target optical system 11. The first step
Optical axis a that passed rhythm 17_FiveDichroic placed above
Since the mirror 31 transmits visible light, the optical axis a_FiveOn extension of
To position it behind the dichroic mirror 31
When the object 38 is placed, the subject
You can see the object 38 through the croic mirror 31
And the optical axis a of the eye E to be examined_E
The approximate optical axis A_FiveCan be matched above. As described above, the illumination light source 30 also serves as a light source for aiming light.
And the light receiving sensor 29 includes one reticle light.
It is configured to detect the aiming light and the measuring light.
As a whole, the measuring optical system 8 itself is miniaturized.
To make the optical measurement unit 1 a handy type
And is advantageously configured. The illumination light source 30 is provided around the optometry window 39 as shown in FIG.
The optical axis a is arranged at the periphery of the optometry window 39._Five
The disk member 40 that can rotate around the housing is the housing of the optical measurement unit 1.
Mounted on the disk member 40 (not shown).
The illumination light source 30 is fixed. The disk member 40 includes water
Two illumination light sources 30 are located on a flat reference diameter line 42
A weight 43 is attached to the place,
The board member 40 and, consequently, the illumination light source 30
Regardless, a constant posture can be maintained. In addition, like this
Unnecessary “swaying” occurs in the illumination light source 30 due to the complicated structure.
The aiming operation is inherently careful and quiet.
Because it is done in a work, there is no problem in practice. And the body
On the reference diameter line 42 by the control circuit 5 built in the unit 2
The illumination light source is controlled to blink separately from other illumination light sources.
You. The posture of the optical measurement unit 1 is inclined with respect to the horizontal direction
In case, the angle on the monitor by the illumination light source on the reference diameter line 42
The coordinates of the film reflection luminescent point can be obtained by the image recognition device 3.
To determine which luminescent spot pair is horizontal.
Only the illumination light source on the reference diameter line is turned on to know
Control to turn off other illumination light sources (even in the reverse control).
Yes). For this control operation, a momentary operation is sufficient,
It is unsightly for the examiner that the monitor screen is dark
There is no such thing as consciousness. In this way, horizontal
Since the inclination angle of the optical measurement unit 1 with respect to the direction is obtained,
From the axis angle (AXIS) value, one of the measurement calculation results,
Correction is made by reducing only the angle, and the exact value is output and displayed
Is done. The pattern of the measuring light projecting optical system 9
Various turns are possible, for example, the optical axis
a_TwoCircular pattern having a predetermined radius formed in an annular shape around
Or a certain distance from the center like this circular pattern
Every 90 °, every 60 ° or every 45 °
The spot pattern arranged at each equi-center angle position is
It is practical. The eye refractive power measuring device of the present embodiment configured as described above
Of the refraction of the eye by the optical system 9 and 10
The setting is performed as follows. FIG. 12 shows that the measuring light is_TwoUpper fixed point O
A perspective view of the light path that enters the cornea through the light path and reaches the retina
FIG. Aimed and in focus
In the constant light projecting optical system 9, the optical axis a_TwoIs the optical axis a of the subject's eye_E
And on the z-axis in the figure, and the measurement light is_Twoupper
The light passes through the fixed point O, enters the point P on the cornea, and enters the point Q on the retina.
Reach. Note that the fixed point O is located in the light receiving optical system 10 for measuring light.
The position of the diaphragm 24 and the position of the corneal surface are conjugate to each other.
When the eyepiece 22 is located at an appropriate position, the measurement light source 15
The measurement light projected from the optical axis a after passing through the eyepiece 22_TwoUp
It is a point that passes through. Optical axis a_EDistance between upper retina and cornea
The separation is d, and the distance between the cornea and the fixed point O is d.₁And Optical axis a_EH to the point P on the cornea₁, x-axis direction
Optical axis a_ELet θ be the inclination in the direction from to point P.
In addition, the refractive index of the subject's eye in the direction inclined by φ with respect to the x-axis
Major axis f₁Suppose there is. Short axis f_TwoIs the major axis f₁Orthogonal to
I have. The component of this point P in the long axis direction is P_f1, Short axis direction
P for minutes_f2Then P_f1= H₁cos (θ-φ) (1) P_f2= H₁sin (θ−φ) (2) Similarly, the corneal surface receives refracting power and projects onto the retina.
For the image to be shadowed (point Q), the optical axis a_EFrom distance h to f₁
Direction and f_TwoEach component of direction Q_f1, Q_f2Is Can be expressed as Horizontal eye refractionVertical eye refractiongiven that, Holds. On the other hand, the image of the projection pattern projected on the retina is
From the viewpoint of the light receiving optical system 10 of the
Selected by the aperture 24 located at a position conjugate with
Only the light beam near the optical axis of the system passes through the aperture 24 and
Guide 27. Also, the position of the aperture 24 is
Is the focal point of the imaging lens 27 passing through the aperture 24.
The light of the entered image travels parallel to the optical axis and
H from optical axis on sa29₀The image is formed at the position of distance.
That is, in the light receiving system, the distance from the optical axis to h on the retina
An image similar to this image is formed on the light receiving sensor 29.
Then h from the optical axis₀Formed at a distance of Where x-axis
Is the inclination of the direction from the optical axis to the point Q with respect to. Ma
In addition, as assumed in the light receiving system, the refractive index of the eye to be examined is
Long axis f₁Is in a direction inclined by φ with respect to the x axis, and the short axis f_Two
Is the major axis f₁Is orthogonal to. And this h and h₀The relationship is
It is represented by equation (9).Here, L is the focal length of the eyepiece 22 and the imaging lens 27.
And a constant determined by the arrangement. From the above assumptions
Q in the light receiving system_f1And Q_f2Is the equation (10) and (11)
Substituting the relation of equation (9) into each of these equations
It is expressed by the equations (12) and (13).  Here, equations (7) and (12), equations (8) and (13)
Thus, the relations of the equations (14) and (15) hold. In equations (14) and (15), operations such as transposition and expansion are
Done, h₀cosψ = Sx, h₀Calculate Sx and Sy as sinψ = Sy
Equations (16) and (17) are obtained. L · h in equations (16) and (17)₁(1 / d₁-D₁) =
A, L ・ h₁(1 / d₁-D_Two) = B, Sx = Acos (θ−φ) cosφ−Bsin (θ−φ) sinφ− (18) Sy = Acos (θ−φ) sinφ−Bsin (θ−φ) cosφ− (19) Expressed easily. In equations (18) and (19), the unknowns to be measured are A, B,
φ, a value θ determined by the light projection pattern
Two values of θ₁, Θ_TwoSx₁, Sy₁, Sx_Two, S
y_TwoTheoretically these unknowns from the four equations that give
Desired. In addition, the correction value of the refractive error is generally a spherical power (SP
H), column surface power (CYL), axis angle (AXIS)
H = D_Two, CYL = D₁−D_Two, AXIS = φ. Here, the light projection pattern is, for example, the optical axis a of the eye E to be inspected._ETo
Optical axis a on the two radial lines of the passing pupil_E4 points facing each other across
Spot pattern. And this 2 wire is horizontal
Direction and vertical direction, and θ₁S for 0 °
x₁= Sx₀, Sy₁= Sy₀, Θ_TwoSx when = 90 °_Two= Sx₉, Sy_Two
= Sy₉Solving the above four equations as Is obtained. Therefore, depending on the spot pattern, as shown in FIG.
Two points P on the x-axis and y-axis projected on the cornea₀, P₉Statue of
In response to the above, formed on the light receiving sensor 29 as shown in FIG.
Point S of the image₀, S₉Coordinates (Sx₀, Sy₀) And (Sx₉, S
y₉) Is measured by the image recognition device 3, the refraction of the eye to be examined
You can know the degree objectively. Hereinafter, FIG. 15 shows the measurement by the eye refractometer according to the present embodiment.
The flow chart shows the steps in order.
You. First, in step 100, the illumination light source 30 is set as the preparation mode.
And the reticle light source 35 is turned on, and the projection light
The source 15 is turned off and goes to step 101. Also,
Step 100 has a timer interrupt by step 100 '
In this step 100 ′, only the illumination light source 30 is used.
Is on, reticle light source 35 and projection light source 15 are off.
It is input to the monitor image in the state where it was done. Moni at this time
In the data image, when the eye E to be examined is in front of the illumination light source 30,
Bright spots and reticle pattern due to corneal reflection of illumination light
Appears, and if there is no eye E, only the reticle pattern
appear. In step 101, the switch of the printer 7 is turned on.
Is determined, and if it is on, step 102
Outputs the printer 7, and then proceeds to step 103, where
If yes, the process proceeds directly to step 103. In step 103, the subject's eye E is located in front of the illumination light source 30.
Is determined. If yes, go to step 104
If not, go back to step 100 and start again.
Each step up to step 103 is repeated. This judgment
Indicates that the corneal reflected light of the illumination light can be detected by the light receiving sensor 29.
The examiner can determine whether or not the
Can be determined. In step 104, the angle of illumination light is set as the aim detection mode.
For each of the x-axis and y-axis of the bright point group due to the film reflected light
Coordinates (x₀, Y₀) By the image recognition device 3
The process proceeds to step 105. In step 105, the x coordinate (x₀)
Absolute value of | x₀| Is the allowable range of the “shift” in the x-axis direction
Judge whether it is smaller than the set x-axis deviation reference value
If it is smaller, the process proceeds to step 106,
Return to step 100 and repeat to step 105
Are repeated. In step 106, the y coordinate (y₀)
Absolute value of y₀| Is the permissible range of “shift” in the y-axis direction
Judge whether it is smaller than the set y-axis deviation reference value
If it is smaller, the process proceeds to step 107,
Return to step 100 and repeat to step 106.
Are repeated. In step 107, the angle of illumination light is set as the focus detection mode.
High-frequency component (H_f)
Determined by the image recognition device 3 and proceed to step 108
You. By detecting the high frequency component in this way,
The method of detecting the in-focus state is implemented only by software.
This is an example of a possible approach, but a more general idea
Of the bright point group including hardware
If the focus state is detected by detecting the strike state,
Good. In step 108, the high-frequency component obtained in step 107
(H_f) Is the contra set as the allowable range of the focus state
It is determined whether the value is greater than the
If not, go to step 109.
Return to Step 100 and go again to Step 108
Is repeated. The aiming situation in steps 104 and 107 above and
The in-focus condition is determined by the reticle pattern and the bright spot on the monitor image.
Positional deviation from group and contrast of bright point group
The examiner looks at this monitor image
The adjustment of the situation and the focusing situation is suggested. In step 109, the angle of illumination light is set as the angle correction mode.
Two bright spots on the reference diameter line 42 in the bright spot group due to the film reflected light
Turn on only each light source corresponding to
The constant light source 15 and the reticle light source 35 are turned off.
And the process proceeds to step 110. In step 110, the image is displayed on the monitor image in step 109.
Line connecting the two bright points and the horizontal reference line on the image (optical
(A horizontal axis of the measuring unit 1) is detected.
Move to step 111. In step 111, the illumination light sources 30 and
The reticle light source 35 is turned off, and the light source 15
Is turned on and input to the monitor image.
Move to 112. At this time, the monitor displays
A fundus putter detected by the light receiving sensor 29 by the science system 10
Image appears for a moment as an image,
Steps for each light source immediately
Proceeding to 112, the measurement light source 15 is turned off, and the illumination light source 30
The same state as in the preparation mode in which the reticle light source 35 is turned on.
To be. The process proceeds from step 112 to step 113, and this step is performed.
In the measurement mode, the measurement light in the measurement mode is received by the light receiving optical system 10.
Whether the signal level input to the sensor 29 is high enough
It is determined whether or not. This is when the eye E is a cataract
When the image signal of the level required for measurement cannot be obtained
Therefore, the check is performed in this step.
If the signal level is high enough in step 113
Goes to step 114 and enters calculation mode,
If there is, go to step 120 and execute error processing.
Will be Examples of error handling in step 120 include:
For example, the display such as “no target” is described in step 116 described below.
Should be displayed on the monitor screen. In step 114, the information is stored in the control circuit 5 in advance.
Measurement data is input to the calculation, and based on this,
Sphericality, which is an element of a lens or contact lens
Number (SPH), column surface power (CYL), and shaft angle (AXIS)
It is. The arithmetic expression of each element is measured by the light emission pattern
It is not uniform because the points are different, but for example a relatively simple example
A total of four spot patterns are projected at each central angle of 90 °.
When casting shadows, the x and y coordinates of each spot must be
Each (Sx₀), (Sx₉), (Sx₁₈), (Sx₂₇), (S
y₀), (Sy₉), (Sy₁₈), (Sy₂₇) And
Spherical power (SPH), cylindrical power (CYL), axis angle
Degree (AXIS) is required. Upon completion of the above calculation, the flow shifts to step 115. In step 115, each element SP determined in step 114
Whether the numerical values of H, CYL, and AXIS are within reasonable numerical ranges
It is determined whether or not the next
Go to step 116, and if it is out of the reasonable range, go to step 121.
The process is shifted to perform error processing. In this step 121
For error processing, for example, display "try again"
It may be displayed on the monitor screen in step 116 described above. In step 116, the calculation result in step 114 or
Display by error processing in step 120 or 121 is monitored.
Appears on the data screen. Note that the calculation result in step 116
The output conditions for displaying
It is possible to switch display for cut lens,
Display the numerical value of the calculation result for each numerical value
It is also possible to set the display stage (STEP value)
You. Also, the distance between the spectacle lens and the cornea (VD value contour)
In the case of a cut lens, it is also possible to set 0).
When step 116 is completed, the preparation mode of step 100 again
Return to In the above-described embodiment, four light spots are used as the light projection pattern.
The case where a pot pattern is used has been described.
Each of n spots centered on the optical axis as other spot patterns
N spot spots that project spot patterns onto radiation
Performing statistical operations on each point using turns
A, B, φ and the spherical power (SP
H), column surface frequency (CYL), and shaft angle (AXIS)
In the case of, the measurement accuracy is increased by setting n to a large value.
It can be dramatically increased. Also, after the spot pattern
As an external light projection pattern, it is continuously annular around the optical axis.
May be a circular pattern, in which case the retina
The pattern projected on top is represented by the formula of an ellipse.
Horizontal bending from the lengths of the major and minor axes
Bending degree D₁And vertical eye refraction D_TwoIs easily sought,
In addition, the inclination angle of the long axis (axis angle) is also the coordinate on the light receiving sensor.
Easily obtained from And the measuring light as described above
Calculation of eye refraction using scientific system and projection pattern
As for the measurement method, the optical measurement unit and the
It is effective only for use with a measuring device with a separated body.
However, what may be adopted for the conventional integrated stationary device is
Of course. 2 to 8 show an optical system for measurement.
The example is merely an embodiment of the present invention, and the optical measuring unit is handy.
Various modifications may be made from this embodiment in order to construct a type.
However, it is possible for those skilled in the art, and FIGS. 16 to 19
The modified example is shown in the example of four spot patterns.
Keep it. FIG. 16 shows the measuring optical system 8 ', and FIG.
Light projecting optical system, Fig. 18 shows measuring light receiving optical system, Fig. 19 shows illumination
Each shows a quasi-optical system. The measuring light projecting optical system 9 'is replaced with a half prism.
A half mirror 45 is used to project infrared light emitting diodes.
Straight optical axis from light source 15 'for light to half mirror 45
a₁', The measurement light reflected at right angles by the half mirror 45
Optical axis a_Two′, The eye E ′ is positioned at
The constant light can be projected into the subject's eye E '. Light source 15 '
The optical axis a from to the half mirror 45₁′, Light source 1
Collimator lens 19 ', pyramid shape in order from 5' side
4 pyramid prism 46, aperture 47, floodlight relay lens 21 ', 4 holes
A mirror 48 and an eyepiece 22 'are arranged. Four-sided pyramid
Rhythm 46 creates a four-point spot pattern
Then, the infrared light from the light source 15 'through the collimator lens 19' is
Optical axis a₁Luminous flux passing through the position around the central angle every 90 °
To separate. Aperture 47 is the focal point of floodlight relay lens 21 '
And four of the four pyramid prisms 46
The luminous flux enters the projection relay lens 21 'after passing through the aperture 47.
Shoot, each with optical axis a₁′ And a four-point light beam
A pot pattern is formed. The four-hole mirror 48 is used for measuring
The measurement light, which is the retinal reflection light in the constant light receiving optical system 10 ', is
A mirror for reflecting at right angles,
Launch surface is optical axis a₁′ Is inclined at 45 ° to the projection optical system
9 'does not block the light path of the projected spot pattern
A small hole is formed in the part corresponding to the optical path
ing. Therefore, the measurement light passing through each hole of the four-hole mirror 48
Enters the eyepiece 22 'as a four-point spot pattern.
The light is reflected at right angles by the half mirror 45 and is
to go into. In the measuring light receiving optical system 10 ', the measuring light is transmitted from the subject's eye E'.
Reverse the optical path of the projection optical system 9 'to the four-hole mirror 48,
The light is reflected at a right angle by the mirror 48. Optical axis a of this reflected light₁₁Up
Has a micro-mirror with a reflective surface parallel to the 4-hole mirror 48
-49 is arranged, and this micro mirror 49
The measuring light is reflected further downward at right angles. Micro mira
Optical axis a below -49_Four′ Along the imaging lens 27 ′ and
A light receiving sensor 29 'is arranged. The aiming optical system 50 partially transmits through the half mirror 45.
The reflected cornea of the illumination light is reflected by the dichroic mirror 31 '.
At right angles to the monitor relay lens 33 '.
Spend. The first 45 ° below the monitor relay lens 33 '
A mirror 51 is arranged, and a reticle pattern is placed on the reflected light path.
A transparent glass reticle plate 52 with
You. The reticle plate 52 is connected to the monitor relay lens 33 '.
And is arranged at a position conjugate with the eye E ′. First
At the position where the reticle plate 52 has passed from the 45 ° mirror 51, the second
The 45 ° mirror 53 of the
It is arranged to reflect. Second 45 ° mirror 53
Below the micromirror in the measuring light receiving optical system 10 '
Optical axis a below 49_Four′ With this light receiving system 10 ′
Sharing the imaging lens 27 'and the light receiving sensor 29'.
I have. Therefore, this aiming optical system 50 is used for monitoring reticle light.
Academic system is built into the monitor camera optical system
Have been. In addition, in the aiming optical system 50, a micro mirror is used.
49 is very small and the aiming light passes through the surrounding area
And its existence does not hinder. Configurations as in the embodiments and modified embodiments described above
According to the operation, for example, as shown in FIG.
Part 2 is placed on a table or other table, and the examiner
Hold only the optical measuring unit 1 of Ip in one hand
And make the subject look at the optotype 38 3-5m away.
The optical measurement unit 1 while looking at the monitor 4
Aiming and focusing while fine-tuning the camera or position
In that case, the examiner only captures the moment and
The calculation is dynamically performed in the main body 2 to calculate the eye refraction.
It is displayed on the monitor 4. Measurement time is therefore very short
What kind of posture the subject is taking
Can also adjust the optical measurement unit 1 to that state,
Measurement becomes easier for the subject,
Relieved of cramped pain.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a schematic configuration of an eye refractometer according to the present embodiment. FIG. 2 is a diagram showing a measuring optical system built in the optical measuring section in the present embodiment. 3 to 8 are diagrams showing each optical system as each element constituting the measuring optical system of the present embodiment. FIG. 3 is a measuring light projecting optical system, and FIG. 4 is a measuring light receiving optical system. FIG. 5 shows an illumination optical system, FIGS. 6 and 7 show a monitor camera optical system and a monitor reticle optical system as aiming optical systems, and FIG. 8 shows a target optical system. 9 and 10 are explanatory diagrams for explaining the aiming state of the corneal reflected light due to the difference in the position of the illumination light source. FIG. 9 shows a state where the aim is shifted, and FIG. 10 shows a state where the aim is in aim. Are respectively shown. FIG. 11 is a diagram showing a state in which the illumination light source and the weight are mounted on the disk member in the present embodiment. FIG. 12 is a perspective view showing an optical path in which the measuring light enters the cornea through a fixed point on the optical axis and reaches the retina in this embodiment. FIG. 13 is a diagram showing, in a coordinate plane, the position of a measurement light pattern projected on the cornea in the present embodiment, and FIG. 14 is a view showing the measurement light projected on the cornea as shown in FIG. 9 is a diagram illustrating a generalized position of an image on a light receiving sensor corresponding to a pattern on a coordinate plane. FIG. 15 is a flowchart showing control of eye refraction measurement according to the present embodiment. FIG. 16 is a view showing a measuring optical system of a modified embodiment, and FIG.
FIG. 18 is a diagram showing the measuring light projecting optical system in FIG. 16, and FIG. 18 is a diagram showing the measuring light receiving optical system in FIG. No.
FIG. 19 is a diagram showing the aiming optical system in FIG. 20th
The figure is a diagram showing a measurement state of the eye refraction according to the present embodiment. DESCRIPTION OF SYMBOLS 1 ... Optical measurement part, 2 ... Body part, 3 ... Image recognition apparatus as a part of control means, 4 ... Monitor, 5 ... Control circuit as a part of control means, 8 ... Optical system for measurement, 9 ... Measurement Light projecting optical system, 10: measuring light receiving optical system, 11: target optical system, 12: monitoring camera optical system as a part of aiming optical system, 13: monitoring reticle as part of the aiming optical system Optics, 14…
Illumination optical system, 15: light source for projecting measurement light, 29: light receiving sensor, 30: illumination light source, 35: reticle light source, 38: target, E ...
Eye to be examined

Claims (1)

(57) [Claims] An optical measuring section (1) having a measuring optical system (8) for objectively measuring an eye refractive index with respect to an eye to be examined.
And a main body (2) for calculating the eye refraction by arithmetically processing the measurement data signal from the optical measurement section (1). The measurement optical system (8) emits measurement light. Measuring light projecting optical system for projecting a light projecting pattern onto the fundus of the eye to be examined (9)
And a measuring light receiving optical system (1) for receiving, on a light receiving sensor (29), a reflected image of the light projecting pattern projected on the fundus of the subject's eye.
0) and the corneal reflection pattern of the aiming light source (30) arranged at a position symmetrical with respect to the optical axis (a ₅ ) of the measuring light incident on the eye to be examined is received by the light receiving sensor (29) and measured. By detecting a deviation of the corneal reflection pattern from the optical axis of light and a change in the intensity of the corneal reflection pattern, the aiming state indicating the focusing state and the focusing state between the measurement optical system (8) and the eye to be inspected is detected. A focusing optical system (12, 13), wherein the main body (2) is configured so that the measuring optical system (8) is in focus and in focus with respect to the eye to be inspected. An eye provided with control means (3, 5) for starting the measurement by the system (9, 10) and calculating the degree of refraction of the eye to be examined based on the image signal from the light receiving sensor (29). Refractometer.