JP3358093B2 - Ophthalmic measurement device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an auto-refractometer and an auto-keratometer having a function of objectively measuring an astigmatic axis of a measuring eye.

[0002]

2. Description of the Related Art Conventionally, in this type of apparatus, an auto-refractometer for objectively measuring the eye refractive power of an eye to be examined and an autokeratometer for measuring the shape of the cornea, an astigmatic axis of the eye to be examined is calculated. Output. In the apparatus as described above, the astigmatic axis of the eye to be examined 1 is represented by θ with reference to the astigmatic axis base direction 3 as shown in FIG. Therefore, the axis 4 orthogonal to the astigmatic axis base direction 3
Is 90 degrees. When the astigmatic axis 2 coincides with the astigmatic axis base direction 3, the angle is 0 degree, but is conventionally expressed as 180 degrees.

In a conventional apparatus, an astigmatic axis is calculated by assuming that the base direction of the astigmatic axis of the eye to be examined matches the base direction of the astigmatic axis calculated by the apparatus by fixing the face of the subject with a chin rest. I was

[0004]

In the prior art as described above, as shown in FIG. 2 (a), the ophthalmologic measuring device 5 faces the eye to be examined and the base direction 7 of the astigmatic axis of the ophthalmologic measuring device 5 is covered. It is good when the measurement is made substantially coincident with the base direction 3 of the astigmatic axis of the optometry 1. For example, as shown in FIG.
Astigmatic axis based ophthalmic measuring apparatus 5 with respect to the astigmatic axis basal direction 3
If the measurement is performed in a state where the bottom direction 7 is rotated by 90 degrees, the astigmatic axis obtained is offset by 90 degrees, and there is a problem that it must be reduced by 90 degrees to obtain the actual astigmatic axis. Was.

The present invention has been made in view of such conventional problems, and an object of the present invention is to provide an image processing apparatus in which the base direction of the astigmatic axis of the ophthalmologic measuring apparatus does not match that of the eye to be examined. It is an object of the present invention to provide an ophthalmologic measuring apparatus that enables correction of an astigmatic axis and obtains a correct astigmatic axis even when measurement cannot be performed facing an eye to be examined.

[0006]

[Means for Solving the Problems] (Claim 1) is provided. Further, (claim 2) is provided.

[0007]

According to the present invention, there is provided means for inputting relative angle information between the base direction of the astigmatic axis of the eye to be examined and the base direction of the astigmatic axis of the ophthalmologic measuring apparatus. When the astigmatic axis base directions do not match, the correct astigmatic axis can be calculated from the relative angle information obtained from the input means.

[0008]

FIG. 3 shows an embodiment of the present invention, in which a switch for informing the ophthalmologic measuring apparatus of the relation between the base direction of the astigmatic axis of the ophthalmologic measuring apparatus and that of the eye to be examined. FIG. 2 is a configuration block diagram illustrating a schematic configuration illustrating the device. In FIG. 3, switches 9, 11, 13
Is a CPU that is arranged in the ophthalmic measurement device and performs measurements, calculations, etc.
15. When the base direction of the astigmatic axis of the eye to be examined and the ophthalmologic measuring apparatus coincide with each other, the switch 9 on which the symbol 10 indicating that the base direction of the astigmatic axis of the ophthalmic measuring apparatus is horizontal to the eye to be examined is drawn. Is in a state orthogonal to 90 degrees, the CPU 13 is informed by pressing the switch 13 on which the symbol 12 indicating this is drawn. The CPU 15 receives the information and determines whether or not to correct the 90-degree offset. If the switch 11 is pressed, the CPU 15 corrects the calculated astigmatic axis by 90 degrees. In addition, when the astigmatic axis correction direction is neither 0 degree nor 90 degrees, the switch 13 is pressed by the switch 14 on which the design 14 indicating the offset is drawn when the operator wants to manually input the offset measured by any method. Later, by operating the numerical value input means 16 capable of inputting the offset information as a numerical value, the information is input to C
The configuration is such that the PU 15 is notified.

FIGS. 4 and 5 show another embodiment of the present invention, illustrating a method for obtaining relative angle information between the base direction of the astigmatic axis of the ophthalmologic measuring apparatus and that of the eye to be examined. Most of auto-reflectometers and auto-keratometers have a form in which an ophthalmologic measurement apparatus is aligned with an eye to be inspected while viewing an external eye image observed through a TV monitor or an eyepiece of the eye to be inspected. For example, as shown in FIG. 4, this external eye image is an external eye image displayed on a TV monitor in a state where the base direction of the astigmatic axis of the eye to be examined substantially matches that of the ophthalmologic measurement apparatus. A straight line 17 indicating the base direction of the astigmatic axis of the ophthalmologic measurement apparatus is superimposed on the external eye image, and the straight line 17 is rotatable. Therefore, as shown in FIG. 5, it is known from the external eye image on the TV monitor that the ophthalmologic measuring apparatus is rotated by θ with respect to the eye to be inspected, and the measurer rotates the straight line 17 to astigmatize the eye to be inspected. By adjusting the rotation angle to the position 18 which is considered to be the base direction of the axis, the rotation angle can be notified to the ophthalmologic measurement apparatus, and correction can be performed.

When an eyepiece is used, a rotatable scale indicating the base direction of the astigmatic axis of the ophthalmologic measuring apparatus is attached to the eyepiece, and the measurer rotates the scale to astigmatize the subject. The rotation angle of the scale when it coincides with the axis base direction may be read by a rotation angle detecting means such as a rotary encoder. Furthermore, in order to accurately determine the base direction of the astigmatic axis of the eye to be examined,
The pupil center position of the subject's eye is determined by a method such as image processing.
The line connecting the center positions can be automatically corrected as the base direction of the astigmatic axis of the subject's eye.

When the ophthalmologic measuring device is small and can be held by hand, there is no guarantee that the ophthalmologic measuring device can be kept horizontal with respect to the ground. It can be corrected based on the base.

[0012]

As described above, according to the present invention, the astigmatic axis can be corrected even when the base direction of the astigmatic axis of the ophthalmologic measuring apparatus does not coincide with that of the eye to be examined. There is an effect that a correct astigmatism axis can be obtained even when it cannot be performed. This means that when the subject cannot sit on a chair, for example, when a bedridden elderly person or a sick person is on a bed, it is difficult to make a measurement facing each other. In such a case, there is an effect that measurement from the temporal side of the subject can be easily performed.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a base direction of an astigmatic axis.

FIG. 2 is a diagram showing the relationship between the base direction of the astigmatic axis of the ophthalmologic measurement apparatus and the base direction of the astigmatic axis of the eye to be examined;
FIG. 2A is a diagram illustrating a state in which the base direction of the astigmatic axis of the ophthalmologic measurement apparatus substantially coincides with the base direction of the astigmatic axis of the eye to be inspected, and FIG.

FIG. 3 is a schematic block diagram illustrating an ophthalmologic measurement apparatus according to an embodiment of the present invention.

FIG. 4 is a diagram for explaining another embodiment of the present invention.

FIG. 5 is a diagram for explaining another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Eye to be examined 2 Astigmatic axis of the eye to be examined 3 Base direction of the astigmatic axis of the eye to be examined 4 Direction perpendicular to the base direction of the astigmatic axis 5 Ophthalmology measuring device 6 Optical system of the ophthalmic measuring device 7 Base direction of the astigmatic axis of the ophthalmic measuring device 8 Measurement optical axis 9 Switch 10 Switch symbol 11 Switch 12 Switch symbol 13 Switch 14 Switch symbol 15 CPU 16 Numerical input means 17 Straight line 18 Rotated straight line

Claims (2)

(57) [Claims] An ophthalmologic measuring apparatus having a function of objectively measuring an astigmatic axis angle of an eye to be inspected, wherein a base direction of an astigmatic axis of the eye to be inspected, which is a reference for measuring the astigmatic axis angle, and the ophthalmologic measurement. Measure the relative angle of the device to the base direction of the astigmatic axis
Is visually confirmed and stored in the ophthalmic measurement device.
Relative angle visually confirmed from the relative angle information
An input unit for selecting an angle corresponding to the degree by a measurer and inputting the input to the ophthalmologic measurement apparatus, based on the information input to the input means, the astigmatic axis base direction of the subject's eye and the astigmatic axis of the ophthalmic measurement apparatus An ophthalmologic measurement apparatus characterized by matching a basal direction. 2. The input means includes an astigmatic axis base of the subject's eye.
The relative angle between the direction and the base direction of the astigmatic axis of the ophthalmic measurement device
A symbol indicating the relationship of
The ophthalmologic measurement apparatus according to claim 1.