KR102645227B1 - Methods of Prism Prescription Using The Difference in the Monocular Response Amplitude - Google Patents

Abstract

The prism prescription method using the difference in the accommodative response range of the monocular of the present invention includes the steps of having a subject gaze at a distant point with a monocular eye and injecting the striae light emitted and diverged from the near point into the pupil; placing lenses with different refractive powers one by one in front of the cornea while observing the retinal reflection; determining the far reaction point Hf according to the first diopter value, which is the refractive power of the lens at which the retinal reflection changes from anterograde to retrograde; having the subject gaze at the near point with a monocular eye and causing the linear light emitted and diverged from the near point to enter the pupil; placing lenses with different refractive powers one by one in front of the cornea while observing the retinal reflection; determining the near reaction point Hn according to the second diopter value, which is the refractive power of the lens at which the retinal reflection changes from accelerating to retrograde; determining the regulatory response range RA from the far reaction point Hf to the near reaction point Hn; determining the distance corrected refraction of each monocular eye from the accommodative response range RA and the distance response point Hf; calculating the accommodative convergence amount of each monocular according to the accommodative response range RA of each monocular, the subject's monocular PD', and the meter angle mA; A step of determining the prism value according to the difference between the controllable runaway amount in the standard eye and the controllable runaway quantity in the non-standard eye is performed.

Description

Prism prescription method using the difference in the accommodative response range of the monocular {Methods of Prism Prescription Using The Difference in the Monocular Response Amplitude}

The present invention is a prism prescription method using the difference in the accommodative response range of the monocular. More specifically, when the accommodative response ranges of both monoculars are different from each other, a difference in the convergence threshold for each monocular occurs to prevent eye fatigue. This is about prism prescription using the difference in the accommodative response range of a single eye.

The purpose of correction for glasses wearers is to correct distance and near refraction. Recently, as we enter the information age, the use of computer monitors and mobile phone displays has increased rapidly, increasing the amount of close-range work. In addition, as the amount of near-distance work increases, the accommodation function in monocular is different, and the number of prism prescriptions due to binocular congestion abnormalities is increasing.

Not only must lenses with refractive degrees inserted into eyeglass frames be designed to match the distance and near refractions, but since the convergence ability from far to near differs for each monocular eye due to differences in the accommodative response of each eye, they are designed as prisms using various inspection methods suited to the characteristics. It should be. Glasses refraction prescriptions based on this type of test method are called binocular vision prescriptions. The present invention relates to prism prescription using the difference in accommodative convergence ratio using the accommodative response of each eye, taking into account the fact that the accommodative response is different for each eye in both eyes.

The binocular focus from far to near is as follows.

1) Tonic convergence: Convergence of physiological comfort

2) Fusional convergence: Convergence for binocular monovision before accommodation

3) Accommodative convergence: Convergence due to regulation

4) Proximal convergence: Convergence due to proximity awareness

Of the four types of congestion mentioned above, convergence congestion and controlled congestion account for most of the congestion.

Since the amount of convergence depends on the angle as shown in Figure 1, its units are degrees °, meter angle mA, and prism diopter △.

The unit of degrees ° is not often used, and the unit of meter angle mA is the reciprocal value of measuring the distance in meters (m) from the eye rotation point to the binocular fixation point, like diopter D, the vergence unit of light flux, and the unit of accommodative force is diopter. It corresponds 1:1 with D.

Prism diopter △ is a unit mainly used by opticians.

△ = PD × mA

It is obtained by the conversion formula. Here, PD is the pupillary distance. Additionally, the distance from the center line of the nose to the center of each pupil is defined as PD', and each PD' in both eyes may be different.

Meanwhile, the ratio of accommodative runaway to the actual accommodative response amount is called the accommodative runaway ratio AC/A, and prism prescription according to the accommodative runaway ratio AC/A begins by first measuring the accommodative runaway ratio AC/A. do.

The method of measuring the adjustable convergence ratio AC/A is the gradient method of measuring the prism diopter, which is measured by adjusting (±) the inspection lens after fixing the inspection distance to 40 to 50 cm in front of the eyes with both eyes open. There is a heterophoria method to find the difference by performing a heterophoria test at a distance and near distance.

The adjustable convergence ratio AC/A is applied to calculate the prism diopter △ of the prism lens that forms the subject's normal convergence angle at each distance.

However, this type of test is performed under the assumption that the range of accommodation is the same as the gaze moves from far to near in both eyes, and the fact that the intraocular response point to stimulation outside the eye is different for each single eye is ignored, and the test is performed on both eyes. There are limits to inaccuracy. In addition, most of the subjects have a different range of intraocular accommodative responses in response to external stimuli from far to near for each monocular, and both accommodative and convergent convergence amounts exist at the same time. Conventional refraction tests are used to measure monocular convergence convergence amounts. Not only is it difficult and inaccurate to obtain the change value, but the subjective refraction method for subjects with both eyes open is less accurate and impractical, so it is hardly used in practice.

Seong Pung-ju (2018), latest edition of Angle Optics, Seoul: Hyunmusa William J. Benjamin (2007), Clinical refraction, Seoul: Korean American Medicine Publishing

The present invention adjusts according to the accommodative response range of each monocular in order to prevent eye fatigue from occurring due to the different convergence ability of each monocular eye as the gaze moves from far to near along the gaze line due to the different accommodative response ranges of each monocular. The purpose is to provide a prism prescription method using the difference in sexual convergence ratio to enable natural binocular vision when the gaze moves from far to near.

The prism prescription method using the difference in the accommodative response range of the monocular of the present invention is,
Having the subject gaze at a distant point of 3 m or more with a single eye and injecting the emitted striated light from a near point within the range of 0.33 to 0.50 m into the pupil;
placing lenses with different refractive powers one by one in front of the cornea while observing the retinal reflection;
determining the far reaction point Hf according to the first diopter value, which is the refractive power of the lens at which the retinal reflection changes from anterograde to retrograde;
having the subject gaze at the near point with a monocular eye and causing the linear light emitted and diverged from the near point to enter the pupil;
placing lenses with different refractive powers one by one in front of the cornea while observing the retinal reflection;
A step of determining the near reaction point Hn according to the second diopter value, which is the refractive power of the lens at which the retinal reflection changes from accelerating to retrograde, is preceded;
The above steps are performed using an autorefractometer, or a refractor and a plate lens;
determining the regulatory response range RA from the far reaction point Hf to the near reaction point Hn;
determining the distance corrected refraction of each monocular eye from the accommodative response range RA and the distance response point Hf;
calculating the accommodative convergence amount of each monocular according to the accommodative response range RA of each monocular, the subject's monocular PD', and the meter angle mA;

The accommodative response range RA of each monocular is divided into three interval values (RA≥3.25D), (2.75D≤RA≤3.00D), and (RA≤2.50D), and the monocular belonging to the larger interval is used as the reference eye. A monocular eye belonging to a section smaller than the accommodative response range RA of the RA is designated as a non-reference eye, and the step of determining the prism value according to the difference between the accommodative convergence amount of the reference eye and the accommodative convergence amount of the non-reference eye is followed. It is characterized by

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The distance corrected refraction of each monocular is,

A) 2.75D ≤ RA ≤ It is 3.00D,

1) If Hf ≤ 1.75D

Far-corrected refraction = Hf-2

2) If Hf ≥ 3.25D

Far-corrected refraction = Hf-3

3) If 2.00D ≤ Hf ≤ 3.00D

Distance corrected refraction = 0

B) RA ≤ 2.50D,

1) If Hf ≤ 1.75D

Far-corrected refraction = (Hf-2) + (RA-3)

2) If Hf ≥ 3.25D

Far-corrected refraction = Hf-3

3) If 2.00D ≤ Hf ≤ 3.00D

Far-corrected refraction = RA-3

C) RA ≥ 3.25D,

1) If Hf ≤ 1.75D

Far-corrected refraction = (Hf-2) + (RA-3)

2) If Hf ≥ 3.25D

Far-corrected refraction = (Hf-3) + (RA-3)

3) If 2.00D ≤ Hf ≤ 3.00D

Far-corrected refraction = RA-3

It is desirable to decide by .

The control reaction range RA is preferably determined by the formula RA=3-(Hf-Hn).

The amount of accommodative congestion for each monocular depends on the accommodative response range RA of each monocular and the subject's monocular PD′.

Monocular accommodative convergence = (monocular PD′ × meter angle mA)/ (monocular accommodative response range RA)

Here, the unit of PD′ is cm

It is desirable to decide.

In the step of determining the prism value according to the difference in the adjustable convergence amount of each monocular,

A) Standard eye 2.75D ≤ RA ≤ When it is 3.00D and the non-standard eye is RA ≤ 2.5,

1) If Hf ≤ 1.75D in the non-standard eye, use basilar intraocular BI,

2) If Hf ≥ 3.25D in non-standard eye, go to basolateral BO

3) If 2.00D ≤ Hf ≤ 3.00D in the non-standard eye, use basilar intraocular BI.

B) The reference eye has RA ≥ 3.25, and the non-reference eye has 2.75D ≤ RA ≤ When 3.00D,

1) If Hf ≤ 1.75D in the non-standard eye, use basilar intraocular BI,

2) If Hf ≥ 3.25D in the non-reference eye, use basilar intraocular BI;

3) If 2.00D ≤ Hf ≤ 3.00D in the non-standard eye, use basilar intraocular BI.

C) When the reference eye has RA ≥ 3.25 and the non-reference eye has RA ≤ 2.50D,

1) If Hf ≤ 1.75D in the non-standard eye, use basilar intraocular BI,

2) If Hf ≥ 3.25D in non-standard eye, go to basolateral BO

3) If 2.00D ≤ Hf ≤ 3.00D in the non-standard eye, use basilar intraocular BI.

It is desirable that the prism shape is determined.

According to the present invention, as the gaze moves from the far point outside the eye to the near point, the difference in the amount of accommodative convergence between both monocular eyes using the difference between the accommodative response of both monocular eyes from the far reaction point inside the eye to the near reaction point and the monocular PD′ is used. There is an effect of obtaining a prism prescription that can implement binocular monovision according to the accommodative response range of the monocular eye.

Figure 1 is a diagram for explaining the unit of congestion amount.
Figure 2 is a diagram for explaining a far-distance reaction point and a near-distance reaction point.
Figure 3 is a diagram for explaining the prism prescription according to the present invention.

Hereinafter, the present invention will be described in more detail with reference to the drawings according to embodiments thereof.

First, each of the subject's monocular eyes is tested. In order to cover the unexamined monocular and prevent the intervention of accommodative force for one monocular, the subject is asked to gaze at a distant point of more than 3 m, and a linear light is emitted into the pupil to enter the pupil. I order it.

Lenses with different refractive powers are placed in front of the cornea, one by one, while observing the retinal reflection of the striated light incident into the monocular pupil. At this time, it is possible to select a lens that changes the retinal reflex from anterograde to retrograde. The refractive power of this lens is called the first diopter value, and the first diopter value is referred to as the far reaction point Hf.

Next, first, each of the subject's monocular eyes is tested. In order to cover the unexamined monocular and prevent the intervention of accommodative force for one monocular, the subject is asked to gaze at a nearby point of 0.33 m and emits a striae light into the pupil. Enter into the pupil. The near point is the subject's working distance and can be set within the range of 0.33 to 0.50 m.

Lenses with different refractive powers are placed in front of the cornea, one by one, while observing the retinal reflection of the striated light incident into the monocular pupil. At this time, it is possible to select a lens that changes the retinal reflex from anterograde to retrograde. The refractive power of this lens is called the second diopter value, and the second diopter value is referred to as the near reaction point Hn.

The series of steps described above can be performed manually using an existing autorefractometer or using a refractor and plate lens.

In case of astigmatism, it is desirable to measure Hf and Hn based on the approximately meridian.

Figure 1 schematically shows the first and second diopters representing the far reaction point Hf and the near reaction point Hn, as well as the far point Pf and the near point Pn.

Based on the retina within the eye, the absolute coordinates of + on the right and - on the left represent the near reaction point Hn, and the far reaction point Hf differs by 3 diopters based on the absolute coordinates.

Therefore, since it is a natural phenomenon that the monocular far reaction point Hf and the near reaction point Hn are measured differently for each person, the range of the far reaction point Hf to the near reaction point Hn, which is the accommodative response in response to stimulation from the far stimulus to the task near, is the accommodative response. The range is defined as RA, and is defined by the equation RA = 3-(Hf-Hn).

The normal case is shown in Figure 2. When the far reaction point Hf is +2.00D, the near reaction point Hn also has the same value of +2.00D with a difference of 3.00D, so the range of the accommodative response RA in the coordinate system of Figure 2 is 3.00. It is calculated as D.

The present invention is for statistical purposes such as patients with monocular blindness, cataracts and corneal ablation procedures such as LASIK and LASEK, pseudomyopia with severe statistical errors, and normal people but requiring subscription due to latent hyperopia. Excluding those who cause errors, a total of 181 people with refractive error who do not have severe diabetes or high blood pressure, which are vascular diseases, and who have relatively good foveal reflexes are selected and based on the measured values, each variable is measured according to statistical techniques. This was achieved by analyzing the correlation between .

There are a total of 125 people with myopia, 68 men and 57 women. 68% are men and 57% are women, and they range in age from 10 to 60. In addition, there were a total of 56 people with manifest hyperopia, 30 men and 26 women, with 53.6% men and 46.4% women.

Frequency analysis of participant demographics(myopia=125, hyperopia=56) Myopia
(31.0 years) Age Frequency Percent(%) Cumulative Percent(%) - 19 22 17.6 17.6 20 - 29 35 28.0 45.6 30 - 39 14 11.2 56.8 40 - 49 24 19.2 76.0 50 - 59 23 18.4 94.4 60 - 7 5.6 100.0 Sub Total 125 100.0 Manifest
Hyperopia
(55.7 years) 40 - 49 4 7.1 7.1 50 - 59 16 28.6 35.7 60 - 36 64.3 100.0 Sub Total 56 100.0 Total 181

As age increases, the negative accommodative lag Lag in both emmetropia and ametropia in myopia models gradually decreases, and after the age of 50, the intraorbital accommodative response range RA decreases due to organic causes of guidance such as latent hyperopia. Change occurs. In order to confirm the suitability of the model according to changes in accommodative power, the accommodative response range RA, which is intraorbital control, was evaluated separately into myopia and overt hyperopia.

Since the intraorbital accommodative response range RA is different for each model, changes in the range of accommodative lag Lag, false relative accommodative power nRA, and addition degree ADD cannot be overlooked. Accommodative response range RA, false relative accommodative force, which are the main variables of the myopia and hyperopia models. There is a need to evaluate the parameters of accommodative force nRA, accommodative lag Lag, and accession ADD to use them effectively in clinical refraction.

Prior to analyzing the path between variables, frequency analysis was performed using SPSS, a statistical analysis package. Then, the variables were covaried and the parameters were evaluated by showing posterior the average value using Analysis Moment Structure (ver. 18) Bayesian (Bayesian structural equation modeling (SEM)) technique. Table 2 shows the covariance analysis of each variable using AMOS. The correlation between variables was confirmed through .

Covariances and correlations (myopia & manifest hyperopia) Model Covariances Correlations Myopia Variable Estimate S· C· P Estimate △RA ↔ △nRA .12 .02 7.38 *** .88 △nRA ↔ △Lag -.04 .01 -4.75 *** -.47 △nRA ↔ △ADD .04 .01 4.59 *** .45 △RA ↔ △Lag -.10 .01 -7.00 *** -.81 △RA ↔ △ADD .05 .02 3.72 *** .36 △Lag ↔△ADD .02 .01 2.48 .013 ^* .23 Manifest
Hyperopia △RA ↔ △nRA .15 .03 5.18 *** .98 △nRA ↔ △ADD .15 .03 5.18 *** .98 △RA ↔ △ADD .16 .03 5.17 *** .97

* Difference between groups is significant at p<0.05 ^* , p<0.01 ^** , p<0.001 ^*** .

According to the above statistical analysis, a method to calculate subscription ADD was found as follows.

Approximately 80% of the examinees had an accommodative response range RA in the range of 2.75D to 3.00D, and the smaller range, 2.5D or less, and the larger range, 3.25D or more, were considered abnormal and classified.

Additionally, if the distance reaction point Hf was less than 1.75D, it was considered myopia, if it was greater than 3.25D, it was considered hyperopia, and if it was between 2.00D and 3.00D, it was considered normal vision.

In optometry, the refractive index of a lens is measured at intervals of 0.25D, so in visual acuity evaluation, the values are calculated at intervals of 0.25.

First, distance correction must be performed before prism prescription. In this case, the distance correction refraction is determined from the accommodative response range RA and the distance response point Hf as follows.

In other words, the distance-corrected refraction of each monocular is,

A) 2.75D ≤ RA ≤ It is 3.00D,

1) If Hf ≤ 1.75D

Far-corrected refraction = Hf-2

2) If Hf ≥ 3.25D

Far-corrected refraction = Hf-3

3) If 2.00D ≤ Hf ≤ 3.00D

Distance corrected refraction = 0

B) RA ≤ 2.50D,

1) If Hf ≤ 1.75D

Far-corrected refraction = (Hf-2) + (RA-3)

2) If Hf ≥ 3.25D

Far-corrected refraction = Hf-3

3) If 2.00D ≤ Hf ≤ 3.00D

Far-corrected refraction = RA-3

C) RA ≥ 3.25D,

1) If Hf ≤ 1.75D

Far-corrected refraction = (Hf-2) + (RA-3)

2) If Hf ≥ 3.25D

Far-corrected refraction = (Hf-3) + (RA-3)

3) If 2.00D ≤ Hf ≤ 3.00D

Far-corrected refraction = RA-3

is determined by

Figure 3 shows a road for explaining the prism prescription of the present invention, where the accommodative response range RA of the right eye (OD) is 2.0D and the accommodative response range RA of the left eye (OS) is 3.00D. When prescribing prisms, the order of reference eyes is determined as (RA≥3.25D) > (2.75D≤RA≤3.00D) > (RA≤2.50D).

When the reference eye in FIG. 3 is set as the left eye according to the order of the reference eyes, convergent convergence occurs in the left eye with no accommodation involved from Pf to Pf', and accommodation occurs in the left eye with accommodation involved from Pf' to Pn. Sexual assault occurs. On the other hand, in the case of the right eye, which is a non-standard eye, accommodative runaway occurs, involving all adjustments from Pf to Pn, and fatigue accumulates in the right eye. In other words, in the left eye, which is the reference eye, convergent and accommodative convergence occurs within the range of 0.33m to 3.00m based on the corneal apex, and in the right eye, accommodative convergence occurs throughout the entire area, resulting in accumulated fatigue or short-distance work. You may complain of difficulties.

For prism prescription, the accommodative convergence amount of each monocular is calculated according to the accommodative response range RA of each monocular and the subject's monocular PD′ using the following equation.

Accommodative convergence amount for each monocular = (monocular PD′ × meter angle mA)/(accommodative response range RA) Here, the unit of PD is cm.

If the monocular PD′ is the same at 3.20 cm and the distance from the vertex of the subject's cornea to the near point is 0.33 m, the required convergence is 3.20cm × 3.03mA = 9.70△. If the size of the accommodative response RA of the right eye (OD), which is the non-reference eye, is 2.00D, and the size of the accommodative response RA of the left eye (OS), which is the reference eye, is 3.00D, the accommodative convergence of the right eye is 9.70△/2.00D = 4.85△. /D, and the left eye's accommodative accommodative aggregation is 9.70△/3.00D=3.23△/D, resulting in a difference of 1.62△ between the reference eye and the non-reference eye, and this difference becomes the prism value.

There are two types of prism lenses: the base IN (BI) type, which is thick on the nose side, and the type (BO, Base Out), which is thick on the ear side.

In the step of determining the prism value according to the difference in the adjustable convergence amount of each monocular,

A) Standard eye 2.75D ≤ RA ≤ 3.00D, and when the non-standard eye is RA ≤ 2.50D,

1) If Hf ≤ 1.75D in the non-standard eye, use basilar intraocular BI,

2) If Hf ≥ 3.25D in non-standard eye, go to basolateral BO

3) If 2.00D ≤ Hf ≤ 3.00D in the non-standard eye, use basilar intraocular BI.

B) The reference eye has RA ≥ 3.25, and the non-reference eye has 2.75D ≤ RA ≤ When 3.00D,

1) If Hf ≤ 1.75D in the non-standard eye, use basilar intraocular BI,

2) If Hf ≥ 3.25D in the non-reference eye, use basilar intraocular BI;

3) If 2.00D ≤ Hf ≤ 3.00D in the non-standard eye, go to basilar intraocular BI.

C) When the reference eye is RA ≥ 3.25 and the non-reference eye is RA ≤ 2.5,

1) If Hf ≤ 1.75D in the non-standard eye, use basilar intraocular BI,

2) If Hf ≥ 3.25D in non-standard eye, go to basolateral BO

3) If 2.00D ≤ Hf ≤ 3.00D in the non-standard eye, go to basilar intraocular BI.

The prism shape is determined.

The subjects' satisfaction with the glasses produced according to this calculation was very high.

Of course, each step of the method described above can be performed in whole or in part by an automated device, and devices implementing this method fall within the scope of the present invention.

Claims (5)

Having the subject gaze at a distant point of 3 m or more with a single eye and injecting the emitted striated light from a near point within the range of 0.33 to 0.50 m into the pupil;
placing lenses with different refractive powers one by one in front of the cornea while observing the retinal reflection;
determining the far reaction point Hf according to the first diopter value, which is the refractive power of the lens at which the retinal reflection changes from anterograde to retrograde;
having the subject gaze at the near point with a monocular eye and causing the linear light emitted and diverged from the near point to enter the pupil;
placing lenses with different refractive powers one by one in front of the cornea while observing the retinal reflection;
A step of determining the near reaction point Hn according to the second diopter value, which is the refractive power of the lens at which the retinal reflection changes from accelerating to retrograde, is preceded;
The above steps are performed using an autorefractometer, or a refractor and a plate lens;
determining the regulatory response range RA from the far reaction point Hf to the near reaction point Hn;
determining the distance corrected refraction of each monocular eye from the accommodative response range RA and the distance response point Hf;
calculating the accommodative convergence amount of each monocular according to the accommodative response range RA of each monocular, the subject's monocular PD', and the meter angle mA;
The accommodative response range RA of each monocular is divided into three interval values (RA≥3.25D), (2.75D≤RA≤3.00D), and (RA≤2.50D), and the monocular belonging to the larger interval is used as the reference eye. A monocular eye belonging to a section smaller than the accommodative response range RA of the RA is designated as a non-reference eye, and the step of determining the prism value according to the difference between the accommodative convergence amount of the reference eye and the accommodative convergence amount of the non-reference eye is followed. Prism prescription method using the difference in the accommodative response range of the featured monocular.
According to claim 1,
The distance corrected refraction of each monocular is,
A) 2.75D ≤ RA ≤ It is 3.00D,
1) If Hf ≤ 1.75D
Far-corrected refraction = Hf-2
2) If Hf ≥ 3.25D
Far-corrected refraction = Hf-3
3) If 2.00D ≤ Hf ≤ 3.00D
Distance corrected refraction = 0
B) RA ≤ 2.50D,
1) If Hf ≤ 1.75D
Far-corrected refraction = (Hf-2) + (RA-3)
2) If Hf ≥ 3.25D
Far-corrected refraction = Hf-3
3) If 2.00D ≤ Hf ≤ 3.00D
Far-corrected refraction = RA-3
C) RA ≥ 3.25D,
1) If Hf ≤ 1.75D
Far-corrected refraction = (Hf-2) + (RA-3)
2) If Hf ≥ 3.25D
Far-corrected refraction = (Hf-3) + (RA-3)
3) If 2.00D ≤ Hf ≤ 3.00D
Far-corrected refraction = RA-3
A prism prescription method using the difference in the accommodative response range of the monocular, characterized in that determined by.
The method of claim 1 or 2,
A prism prescription method using the difference in the accommodative response range of a single eye, characterized in that the accommodative response range RA is determined by the equation RA=3-(Hf-Hn).
The method of claim 1 or 2,
The amount of accommodative convergence for each monocular depends on the accommodative response range RA of each monocular and the subject's monocular PD'.
Monocular accommodative convergence = (monocular PD′ × meter angle mA)/monocular accommodative response range RA
Here, the unit of PD′ is cm
A prism prescription method using the difference in the accommodative response range of the monocular, characterized in that it is determined by.
According to claim 1,
In the step of determining the prism value according to the difference in the adjustable convergence amount of each monocular,
A) Standard eye 2.75D ≤ RA ≤ 3.00D, and when the non-standard eye is RA ≤ 2.50D,
1) If Hf ≤ 1.75D in the non-standard eye, use basilar intraocular BI,
2) If Hf ≥ 3.25D in non-standard eye, go to basolateral BO
3) If 2.00D ≤ Hf ≤ 3.00D in the non-standard eye, use basilar intraocular BI.
B) The reference eye has RA ≥ 3.25, and the non-reference eye has 2.75D ≤ RA ≤ When 3.00D,
1) If Hf ≤ 1.75D in the non-standard eye, use basilar intraocular BI,
2) If Hf ≥ 3.25D in the non-reference eye, use basilar intraocular BI;
3) If 2.00D ≤ Hf ≤ 3.00D in the non-standard eye, use basilar intraocular BI.
C) When the reference eye is RA ≥ 3.25D and the non-reference eye is RA ≤ 2.50D,
1) If Hf ≤ 1.75D in the non-standard eye, use basilar intraocular BI,
2) If Hf ≥ 3.25D in non-standard eye, go to basolateral BO
3) If 2.00D ≤ Hf ≤ 3.00D in the non-standard eye, use basilar intraocular BI.
A prism prescription method using the difference in the accommodative response range of a single eye, characterized in that the prism shape is determined.