CN102914879A - Design method of free-form surface glasses based on wave-front technology - Google Patents

Abstract

The invention relates to a design method of free-form surface glasses based on a wave-front technology, which has the technical characteristics that length data of each part of an eye axis is substituted into an eye optical model; a cornea surface curvature and a corneal topography data replace the eye model; wave-front aberration data of actual human eyes is converted into a corresponding value under photopic vision; an individualized eye model which accords with an actual human eye visual property is established; a lens is arranged in front of the individualized eye model; the lens and the individualized eye model are considered as a uniform lens-eye optical system and a certain visual field angle is arranged for the system; a plurality of structures with different angles are arranged for the lens-eye optical system; and the free-form surface glasses according with an individual eye visual property, and the diopter and the structural parameters thereof are calculated. The free-form surface lens obtained by the design method disclosed by the invention, low-order aberration of the eyes can be corrected and high-order aberration can be better corrected; and the design method has the advantages of simplicity and convenience for designing, objectiveness and accuracy, and high precision.

Description

Method for designing based on the free form surface glasses of wave front technology

Technical field

The invention belongs to the vision correcting technical field, especially a kind of method for designing of the free form surface glasses based on wave front technology.

Background technology

Because human eye has complicated dioptric system, except having the such low order aberration of defocus and astigmatism, also has various irregular higher order aberratons, such as spherical aberration, coma, clover is poor etc., and they affect the visual quality of human eye equally.Studies show that, only depend on effectively correct for higher order aberrations of ball-post mirror.In addition, although aspherical lens has moved towards market, existing aspheric mirror there is no the ability of correcting the human eye higher order aberratons mainly as the physical pattern that changes glasses.We also once proposed can correct spherical aberration, the aspheric surface glasses of astigmatism (Chinese science: technological sciences, 2012,42 (5): 537-547).But find that aspheric mirror only can be corrected the spherical aberration item in the higher order aberratons, and is invalid for other correction for higher order aberrations.

Secondly, when human eye is looked thing, must guarantee that eyes can clearly look thing in certain visual field, require generally speaking total field angle to be ± 7 °; Simultaneously, people's eyeball rotates, rotational angle generally can reach (20 °, but glasses are relatively static, cause the optical axis of human eye and the optical axis deviation of eyeglass.So how the guarantee glasses are fit to the different angles rotation of eyeball, can have certain blur-free imaging field range again when looking thing simultaneously.

For above problem, US Patent No. 2002/0196412A1 has proposed two kinds of frame eyeglasses schemes of correcting the human eye higher order aberratons, the first scheme is divided into two discontinuity zones with eyeglass, (visual field is interior among a small circle to be free form surface in central authorities 1, be used for correct for higher order aberrations, the peripheral region is basic arc sphere; Alternative plan is that (the wavefront aberration data of visual field are applied to other field angle by the eyeball rotation, then are weighted optimization 0.This patent does not address the above problem: only can clearly look thing in 1 ° of field angle during direct-view, depart from this zone just without rectification effect; Equally, also can only guarantee the clear thing of looking in 1 ° of visual field when eyeball rotates to an angle, therefore, this patent is failed to provide any eyeglass and is tested and join the result, and lies on the table so far.

Summary of the invention

The object of the invention is to overcome the deficiencies in the prior art, a kind of method for designing of the free form surface glasses based on wave front technology is provided, the method can not only be corrected the low price aberration of human eye, and can optimization correct the human eye higher order aberratons.

The present invention solves its technical matters and takes following technical scheme to realize:

A kind of method for designing of the free form surface glasses based on wave front technology may further comprise the steps:

Step 1: with the length data substitution Gull strand-Le Grand optics of the eye model of axis oculi each several part;

Step 2: use anterior corneal surface curvature and the above-mentioned phantom eye of corneal topography data replacement with the cornea face type of Reality simulation human eye, and be converted into Zernike Fringe Sag form;

Step 3: the wavefront aberration data of actual human eye is converted into respective value under the photopic vision;

Step 4: the wavefront aberration data under the photopic vision condition is as desired value,, as variable phantom eye is optimized with crystalline lens front surface curvature and face shape parameter thereof, sets up the personalized eye model that realistic human eye is looked the thing characteristic;

Step 5: eyeglass is set before personalized eye model, eyeglass and personalized eye model are considered as unified mirror-optics of the eye system, be characterized as system certain field angle is set for the thing of looking of human eye;

Step 6: the rotating rule of eyeball is that mirror-optics of the eye system arranges the multiplet of different angles when looking thing;

Step 7: the rear surface of eyeglass is set to encircle curved surface, the front surface of eyeglass is set to free form surface, the angle that two radius-of-curvature by optimizing the ring curved surface and ring curved surface rotate around optical axis is corrected out of focus and the astigmatism of human eye, the Zernike multinomial coefficient of optimizing free form surface is corrected the higher order aberratons of human eye, finally calculate meet free form surface wavefront glasses that individual eye looks the thing feature with and refractive diopter and structural parameters.

And the mathematical model of the Zernike Fringe Sag form in the described step 2 is:

$z={\mathrm{<figure-callout\; id="0"\; label="z"\; filenames="HDA00002362847600031.png,HDA00002362847600041.png"\; state="\{\{state\}\}">z</figure-callout>}}_0+\frac{c(x^2+y^2)}{1+\sqrt{1-c^2(x^2+y^2)}}+\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{A}_i{Z}_i(x,y)$

Wherein, z ₀Be constant, c is the curvature of anterior surface of cornea benchmark sphere, Z _iThe polynomial i item of (x, y) expression Zernike, A _iBe the coefficient of corresponding entry, N is selected item number.

And field angle is 0 ° and ± 7 ° of visual fields in the described step 5.

And multiplet comprises the minor structure of 9 kinds of different rotary angles in the described step 6, corresponding 0 ° respectively, eyeball horizontally rotates ± 10 °, ± 20 °, vertical rotation ± 10 °, ± 20 °.

And the expression formula of ring curved surface face type is in the described step 7:

$z=\frac{c_x{x}^2+c_y{\mathrm{<figure-callout\; id="2"\; label="y"\; filenames="HDA00002362847600051.png,HDA00002362847600061.png"\; state="\{\{state\}\}">y</figure-callout>}}^2}{1+\sqrt{1-(1+k_x)c_x^2{x}^2-(1+k_y)c_y^2{y}^2}}$

Wherein, c _x, c _yRespectively x, the reference sphere curvature of face of y direction, k _x, k _yRespectively x, the conical surface degree of y direction.

And, described k _x=0, k _y=0.

And described step 7 is calculated dioptric method and is:

${\mathrm{<figure-callout\; id="1"\; label="P"\; filenames="HDA00002362847600041.png,HDA00002362847600051.png"\; state="\{\{state\}\}">P</figure-callout>}}_1=(n_{\mathrm{glass}}-1)(\frac{1}{R_{\mathrm{base}}}-\frac{1}{R_1}+\frac{d(n_{\mathrm{glass}}-1)}{R_{\mathrm{base}}{R}_1{n}_{\mathrm{glass}}})$

${\mathrm{<figure-callout\; id="2"\; label="P"\; filenames="HDA00002362847600051.png,HDA00002362847600061.png"\; state="\{\{state\}\}">P</figure-callout>}}_2=(n_{\mathrm{glass}}-1)(\frac{1}{R_{\mathrm{base}}}-\frac{1}{R_2}+\frac{d(n_{\mathrm{glass}}-1)}{R_{\mathrm{base}}{R}_2{n}_{\mathrm{glass}}})$

Wherein, P ₁And P ₂The diopter of two orthogonal directionss of difference representative ring curved surface, unit is D, n _GlassThe refractive index of expression eyeglass, R _BseThe radius-of-curvature of expression lens front surface, d represents the center thickness of eyeglass, establishes P ₁Be sphericity Ps, post degree Pc=P ₂-P ₁

And the front surface of glasses is set to free form surface in the described step 7, constructs with Zernike Fringe Sag high-order moment, and its expression formula is:

$z={\mathrm{<figure-callout\; id="0"\; label="z"\; filenames="HDA00002362847600031.png,HDA00002362847600041.png"\; state="\{\{state\}\}">z</figure-callout>}}_0+\frac{c(x^2+y^2)}{1+\sqrt{1-c^2(x^2+y^2)}}+\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{A}_i{Z}_i(x,y)$

Wherein, z ₀Be constant, c is the curvature of anterior surface of cornea benchmark sphere, Z _iThe polynomial i item of (x, y) expression Zernike, A _iBe the coefficient of corresponding entry, N is selected item number.

Advantage of the present invention and good effect are:

The present invention is on the basis of the original phantom eye of Gul l strand-Le Grand, and in conjunction with important parameters such as axiallength, corneal topography and wave front aberrations, the realistic human eye of personalized eye model that builds up look the thing feature, reach farthest similar to tested eye; Regard glasses and personalized eye model as unified mirror-optics of the eye system simultaneously, system is arranged the certain visual angle degree, satisfy human eye in the clear feature of looking thing in certain visual field; And system is set to multiplet, corresponding to oculogyral situation; At last the glasses front and rear surfaces is set to respectively encircle curved surface and free form surface, reaches the rectification low order aberration, the simultaneously effect of correct for higher order aberrations by optimizing glasses front-back type.The free surface lens that the present invention obtains can not only correction ocular low order aberration, and also played good correcting for higher order aberratons, improved the visual quality of human eye, have the advantage that design is easy, objective and accurate, precision is high.

Description of drawings

Fig. 1 is design flow diagram of the present invention;

Fig. 2 is mirror-optics of the eye system architecture synoptic diagram;

Fig. 3 is that tested eye is through correcting the MTF synoptic diagram of front direct-view;

Fig. 4 is that tested eye is through correcting the MTF synoptic diagram of 20 ° of front rotations;

Fig. 5 is the MTF synoptic diagram of tested eye direct-view after correcting;

Fig. 6 is that tested eye rotates 20 ° MTF synoptic diagram after correcting.

Embodiment

Below in conjunction with accompanying drawing the embodiment of the invention is further described.

A kind of method for designing of the free form surface glasses based on wave front technology as shown in Figure 1, may further comprise the steps:

Step 1: with the length data substitution Gull strand-Le Grand optics of the eye model of axis oculi each several part;

In this step, use conventional means (for example medical supersonic thicknessmeter) that the each several part length to axis oculi of axis oculi is measured, obtain the length data of axis oculi each several part: anterior chamber, crystalline lens, vitreum are at the axial thickness of eye.

This step just with above-mentioned data substitution to Gul l strand-Le Grand optics of the eye model;

Step 2: use anterior corneal surface curvature and corneal topography diagram data, the cornea of replacing in the Gullstrand-Le Grand optics of the eye model is used for the cornea face type of Reality simulation human eye, and utilizes MATLAB software that actual type of cornea is converted into Zernike Fringe Sag form among the optical design software ZEMAX:

$z={\mathrm{<figure-callout\; id="0"\; label="z"\; filenames="HDA00002362847600031.png,HDA00002362847600041.png"\; state="\{\{state\}\}">z</figure-callout>}}_0+\frac{c(x^2+y^2)}{1+\sqrt{1-c^2(x^2+y^2)}}+\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{A}_i{Z}_i(x,y)$

Wherein, z ₀Be constant, c is the curvature of anterior surface of cornea benchmark sphere, Z _iThe polynomial i item of (x, y) expression Zernike, A _iBe the coefficient of corresponding entry, N is selected item number; And cornea face type original in the phantom eye is replaced with the above-mentioned actual corners face type that represents with Zernike Fringe Sag form.

This step is just utilized anterior corneal surface curvature and corneal topography diagram data, and the acquisition of concrete anterior corneal surface curvature and corneal topography diagram data adopts conventional means can obtain (for example using the medical cornea activity mapping instrument).

Step 3: wavefront aberration data is converted into respective value under the photopic vision;

The measurement of wavefront aberration data is under dark room conditions, and pupil diameter naturally is amplified in the above situation of 6mm and measures, and every eye are all measured averages more than 3 times or 3 times.Because the diameter of pupil is 3-4mm under the photopic vision condition, therefore use MATLAB software that the original wavefront aberration data is converted to wavefront aberration data corresponding under the photopic vision condition.

Step 4: in ZEMAX software, wavefront aberration data under the photopic vision condition is as desired value, utilize the optimizational function of software that phantom eye is optimized, crystalline lens front surface curvature and face shape parameter thereof as variable, are namely set up the personalized eye model of realistic opthalmic optics's characteristic after the optimization;

As desired value, optimize so that the curvature of crystalline lens front surface is born the out of focus of human eye as variable by crystalline lens front surface curvature and face type thereof with the wavefront aberration data under the photopic vision condition for this step, and its surperficial face type is born astigmatism and the higher order aberratons of human eye.Thereby so that the wave front aberration of phantom eye is consistent with the wave front aberration value of actual human eye.

Step: 5: add eyeglass with the personalized eye model basis of optimizing above-mentioned, regard eyeglass and human eye as unified optical system, that considers human eye reality looks the thing feature: the clear thing of looking in certain visual field, the total field angle of General Requirements ± 7 ° arranges ± 7 ° field angle so we are mirror-optics of the eye system;

Fig. 2 is mirror-optics of the eye system architecture synoptic diagram, and the position of eyeglass is arranged on the front 13mm place of personalized eye model, material selection refractive index 1.6, the resin of Abbe number 36.

Step 6: the rotation of eyeball when looking thing, for mirror-optics of the eye system arranges the multiplet of different angles.Consider that actual human eye eyeball when looking thing can rotate, rotational angle generally can reach ± and 20 °, so the present invention is provided with nine minor structures.Correspond respectively to eyeball horizontally rotate 0 °, ± 10 °, ± 20 °, vertically rotate ± 10 °, ± 20 °, center position is set in 27mm place, summit behind the eyeglass.

Step 7: the rear surface of eyeglass is set to encircle curved surface face type and is used for correcting defocus and astigmatism, the front surface of eyeglass is set to the higher order aberratons that the free form surface type is used for correction ocular, by optimizing the Zernike multinomial coefficient in the free form surface, the curvature of ring curved surface pairwise orthogonal direction and the angle that this face rotates around optical axis, corrected simultaneously the free form surface wavefront glasses of low order aberration and higher order aberratons, and the structural parameters of glasses and refractive diopter.

The face type of rear surface is set to encircle curved surface in this step, and its expression formula is:

$z=\frac{c_x{x}^2+c_y{\mathrm{<figure-callout\; id="2"\; label="y"\; filenames="HDA00002362847600051.png,HDA00002362847600061.png"\; state="\{\{state\}\}">y</figure-callout>}}^2}{1+\sqrt{1-(1+k_x)c_x^2{x}^2-(1+k_y)c_y^2{y}^2}}$

In the formula, c _x, c _yRespectively x, the reference sphere curvature of face of y direction, k _x, k _yBe respectively x, the conical surface degree of y direction is 0 with its value among the present invention.

Curvature and the ring curved surface of setting rear surface ring curved surface pairwise orthogonal direction are variable around the angle that optical axis rotates, and are optimized in ZEMAX.

Front surface face type is set to free form surface in this step, constructs this asymmetrical complex optical surfaces with Zernike Fringe Sag high-order moment in ZEMAX, and its expression formula is:

$z={\mathrm{<figure-callout\; id="0"\; label="z"\; filenames="HDA00002362847600031.png,HDA00002362847600041.png"\; state="\{\{state\}\}">z</figure-callout>}}_0+\frac{c(x^2+y^2)}{1+\sqrt{1-c^2(x^2+y^2)}}+\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{A}_i{Z}_i(x,y)$

In the formula, z ₀Be constant, c is the curvature of anterior surface of cornea benchmark sphere, Z _iThe polynomial i item of (x, y) expression Zernike is the coefficient of corresponding entry, and N is selected item number.The present invention selects 29

Zernike multinomial coefficient A with free form surface ₄To A ₂₉Be made as variable, each visual field to each structure in majorized function assigns weight, and according to individual aberration, different weights is set, but all is the weights that rationally strengthen under the direct-view structure, and the weight of the lower 0 ° of visual field of each structure.Then whole mirror-eye system is optimized.Namely obtain the good mirror of image quality-optics of the eye system, obtain simultaneously correcting the structural parameters of the free form surface wavefront glasses of low order aberration and higher order aberratons.

According to the parameter of ring curved surface after optimizing, can calculate the refractive diopter of eyeglass, computing method are as follows:

${\mathrm{<figure-callout\; id="1"\; label="P"\; filenames="HDA00002362847600041.png,HDA00002362847600051.png"\; state="\{\{state\}\}">P</figure-callout>}}_1=(n_{\mathrm{glass}}-1)(\frac{1}{R_{\mathrm{base}}}-\frac{1}{{\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="HDA00002362847600041.png,HDA00002362847600051.png"\; state="\{\{state\}\}">R</figure-callout>}}_1}+\frac{d(n_{\mathrm{glass}}-1)}{R_{\mathrm{base}}{R}_1{n}_{\mathrm{glass}}})$

${\mathrm{<figure-callout\; id="2"\; label="P"\; filenames="HDA00002362847600051.png,HDA00002362847600061.png"\; state="\{\{state\}\}">P</figure-callout>}}_2=(n_{\mathrm{glass}}-1)(\frac{1}{R_{\mathrm{base}}}-\frac{1}{{\mathrm{<figure-callout\; id="2"\; label="R"\; filenames="HDA00002362847600051.png,HDA00002362847600061.png"\; state="\{\{state\}\}">R</figure-callout>}}_2}+\frac{d(n_{\mathrm{glass}}-1)}{R_{\mathrm{base}}{R}_2{n}_{\mathrm{glass}}})$

In the formula, P ₁And P ₂The diopter that represents respectively respective direction, n _GlassThe refractive index of expression eyeglass, R _BseThe radius-of-curvature of expression lens front surface, d represents the center thickness of eyeglass, P ₁Be decided to be sphericity Ps, post degree Pc=P ₂-P ₁

The below is elaborated to the design's method with an embodiment:

The length of table 1 each ingredient of axis oculi that to be two tested eyes measure by the medical supersonic thicknessmeter:

Each ingredient length of table 1 axis oculi

Unit (mm)	The anterior chamber	Crystalline lens	Vitreum	Total length
						1	3.84	3.36	18.18	25.39
2	3.55	3.46	19.18	26.18

Table 2 is after two tested eyes are measured actual corners face types through the medical cornea activity mapping instruments, utilizes MATLAB software that actual face type is converted into parameter after the Zernike Fringe Sag high-order moment form and corneal curvature radius.Limited space, table 2 only illustrate A4～A9 item.

The structural parameters of table 2 cornea

Table 3 is that two tested eyes utilize the measurement of Medical eye wavefront analyzer and utilize MATLAB software to be converted into wave front aberration value corresponding under the photopic vision condition.Use the polynomial form of Zernike to represent C _i(i=0,1,2,3 ...) be each coefficient of polynomial expression, for saving the space, only with C ₃～C ₁₄Item is listed.Because C ₀～C ₂Xiang represents constant term and the item that tilts, without practical significance, so unlisted.

The tested wavefront aberration data of table 3

Table 4 is the structural parameters of the free form surface of two tested eye designs.Wherein, P _BaseThe refractive power that represents basic arc, Ps represent equivalent sphericity, and Pc represents equivalent post degree, and Axis is the axis of astigmatism angle, Zernike coefficient A _i(unit: mm) the face shape parameter of expression free form surface, limited space, only list i=4 to 15:

The structural parameters of table 4 free surface lens

?	1	2
			P bse	4.00D	4.50D
P s	-4.74D	-3.78D
			P c	-1.03D	-1.42D
Axis	170.3°	10.3°
			A 4	-0.0065	-0.4009
A 5	0.0168	-0.7483
			A 6	-0.0044	0.0019
A 7	-0.0207	-1.4548
			A 8	-0.0061	0.0205
A 9	-0.0230	-0.1799
			A 0	0.0074	-1.4327
A 11	-0.0123	-0.0271
			A 12	-0.0281	-0.3361
A 13	-0.0028	0.0054
			A 14	-0.0258	-0.3888
A 15	-0.0033	0.0181

The rectification effect of free form surface can be passed judgment on more intuitively by the MTF family curve of mirror-eye system.Fig. 3 to Fig. 6 has provided the MTF curve of tested eye before and after free surface lens is corrected.Limited space is only listed tested 6 MTF curve map.Among the figure, blue curve is 0 ° of visual field, 7 ° of visual fields of green expression, and T represents meridian direction, S represents sagitta of arc direction.Wherein figure (a) and (b) be respectively free form surface correct before direct-view and the situation of rotating 20 °, (c) and (d) then be the MTF after the rectification.

For the effect that better explanation free form surface is corrected, table 5 listed two tested eyes ball-post correct and ball-post correct add free form surface and correct after, look at straight under 0 ° of visual field, look at the mtf value under 5 typical space frequencies under 7 ° of visual fields straight.

The mtf value of the mirror-eye system of two tested eyes of table 5

This shows that through after the rectification of free form surface, two MTFs of tested eye 7 ° of visual fields have greatly improved, the simultaneously improvement for 0 ° of view field imaging quality also has certain effect.In 7 ° of visual fields of direct-view, corresponding to spatial frequency 40cycle/mm, 80cycle/mm, 100cycle/mm, 125cycle/mm, 150cycl e/mm, the MTF of tested eye 1 has improved respectively 22.3%, 44.42%, 50.17%, 55.75%, 60.08%; The MTF of tested eye 2 has improved respectively 8.37%, 27.65%, 39.89%, 55.42%, 66.67%.

Embodiment of the present invention is illustrative, rather than determinate, so the present invention is not limited to the embodiment described in the embodiment.Other embodiments that every technical scheme according to the present invention draws belong to the scope of protection of the invention equally.

Claims (8)

1. method for designing based on the free form surface glasses of wave front technology is characterized in that: may further comprise the steps:

Step 1: with the length data substitution Gull strand-Le Grand optics of the eye model of axis oculi each several part;

Step 2: use anterior corneal surface curvature and the above-mentioned phantom eye of corneal topography data replacement with the cornea face type of Reality simulation human eye, and be converted into Zernike Fringe Sag form;

Step 3: the wavefront aberration data of actual human eye is converted into respective value under the photopic vision;

Step 4: the wavefront aberration data under the photopic vision condition is as desired value,, as variable phantom eye is optimized with crystalline lens front surface curvature and face shape parameter thereof, sets up the personalized eye model that realistic human eye is looked the thing characteristic;

Step 5: eyeglass is set before personalized eye model, eyeglass and personalized eye model are considered as unified mirror-optics of the eye system, be characterized as system certain field angle is set for the thing of looking of human eye;

Step 6: the rotating rule of eyeball is that mirror-optics of the eye system arranges the multiplet of different angles when looking thing;

Step 7: the rear surface of eyeglass is set to encircle curved surface, the front surface of eyeglass is set to free form surface, the angle that two radius-of-curvature by optimizing the ring curved surface and ring curved surface rotate around optical axis is corrected out of focus and the astigmatism of human eye, the Zernike multinomial coefficient of optimizing free form surface is corrected the higher order aberratons of human eye, finally calculate meet free form surface wavefront glasses that individual eye looks the thing feature with and refractive diopter and structural parameters.

2. the method for designing of the free form surface glasses based on wave front technology according to claim 1, it is characterized in that: the mathematical model of the Zernike Fringe Sag form in the described step 2 is:

$z=z_0+\frac{c(x^2+y^2)}{1+\sqrt{1-c^2(x^2+y^2)}}+\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{A}_i{Z}_i(x,y)$

Wherein, z ₀Be constant, c is the curvature of anterior surface of cornea benchmark sphere, Z _iThe polynomial i item of (x, y) expression Zernike, A _iBe the coefficient of corresponding entry, N is selected item number.

3. the method for designing of the free form surface glasses based on wave front technology according to claim 1, it is characterized in that: field angle is 0 ° and ± 7 ° of visual fields in the described step 5.

4. the method for designing of the free form surface glasses based on wave front technology according to claim 1, it is characterized in that: multiplet comprises the minor structure of 9 kinds of different rotary angles in the described step 6, corresponding 0 ° respectively, eyeball horizontally rotates ± 10 °, ± 20 °, vertical rotation ± 10 °, ± 20 °.

5. the method for designing of the free form surface glasses based on wave front technology according to claim 1, it is characterized in that: the expression formula of ring curved surface face type is in the described step 7:

$z=\frac{c_x{x}^2+c_y{y}^2}{1+\sqrt{1-(1+k_x)c_x^2{x}^2-(1+k_y)c_y^2{y}^2}}$

Wherein, c _x, c _yRespectively x, the reference sphere curvature of face of y direction, k _x, k _yRespectively x, the conical surface degree of y direction.

6. the method for designing of the free form surface glasses based on wave front technology according to claim 5 is characterized in that: described k _x=0, k _y=0.

7. the method for designing of the free form surface glasses based on wave front technology according to claim 1, it is characterized in that: described step 7 is calculated dioptric method and is:

$P_1=(n_{\mathrm{glass}}-1)(\frac{1}{R_{\mathrm{base}}}-\frac{1}{R_1}+\frac{d(n_{\mathrm{glass}}-1)}{R_{\mathrm{base}}{R}_1{n}_{\mathrm{glass}}})$

$P_2=(n_{\mathrm{glass}}-1)(\frac{1}{R_{\mathrm{base}}}-\frac{1}{R_2}+\frac{d(n_{\mathrm{glass}}-1)}{R_{\mathrm{base}}{R}_2{n}_{\mathrm{glass}}})$

Wherein, P ₁And P ₂The diopter of two orthogonal directionss of difference representative ring curved surface, unit is D, n _GlassThe refractive index of expression eyeglass, R _BseThe radius-of-curvature of expression lens front surface, d represents the center thickness of eyeglass, establishes R ₁Be sphericity Ps, post degree Pc=P ₂-P ₁

8. the method for designing of the free form surface glasses based on wave front technology according to claim 1, it is characterized in that: the front surface of glasses is set to free form surface in the described step 7, construct with Zernike Fringe Sag high-order moment, its expression formula is:

$z=z_0+\frac{c(x^2+y^2)}{1+\sqrt{1-c^2(x^2+y^2)}}+\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{A}_i{Z}_i(x,y)$

Wherein, z ₀Be constant, c is the curvature of anterior surface of cornea benchmark sphere, Z _iThe polynomial i item of (x, y) expression Zernike, A _iBe the coefficient of corresponding entry, N is selected item number.

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