CN105496349A - Hartmann measurement system for human eye chromatic aberration - Google Patents

Abstract

The invention discloses a Hartmann measurement system for human eye chromatic aberration. According to the system, light emitted from multi-wavelength beacons enters a pupil of a human eye through a collimating mirror, beam combination mirrors, a diaphragm and a beam splitter mirror I; back scattered light subjected to diffuse reflection from the eye ground passes through the pupil, light with various wavelengths enters corresponding Hartmann wave-front sensors through beam splitter mirrors, a focusing system, an aperture matching system and a filter, and collected wave-front data are transmitted to a computer by CCDs (charge coupled devices) of the Hartmann wave-front sensors. The measured wave-front data are converted into Zernike polynomials by the computer, and axial chromatic aberration of the human eye is calculated according to fourth out-of-focus items of Zernike polynomial coefficients with various wavelengths; local transverse chromatic aberration corresponding to the human eye pupil position is calculated according to wavelength position deviation of each micro lens (or prism) array of the Hartmann wave-front sensors. Under the premise of simultaneous measurement of the transverse chromatic aberration and the axial chromatic aberration of the human eye, the influence of retina jitter such as human eye micro-rapid glancing and the like as well as dynamic aberration on chromatic aberration data is avoided.

Description

Hartmann's human eye chromatism measurement system

Technical field

The present invention relates to the technical field of human eye chromatism measurement, be specifically related to a kind of Hartmann's human eye chromatism measurement system.

Background technology

The eye structure of the mankind is complicated, and its imaging system is primarily of cornea, anterior chamber, iris, crystalline lens and vitreous body composition.The dioptric degree varies sample of every part, and majority of case we wish study eye ground after the imaging system of human eye.Multi-wavelength light enters the process of eye ground through this light penetration system, and the inevitable generation with aberration, there are some researches show, the irregular main cause being lateral chromatic aberration and producing of cornea.In other words, no matter be the eye ground imaging wishing to carry out multi-wavelength, or the evaluation of artificial intraocular lenses (IOL) eye required for cataract operation, also has that the colour difference evaluation of other preoperative, postoperative eyes is measured human eye aberration all possibly, calibration and compensation.Therefore, the measurement of research human eye aberration has earth shaking meaning, is retina image-forming Quality advance and cataract patient clear important prerequisite of looking thing under visible light.

By the knowledge of geometric optics, human eye aberration can be divided into axial chromatic aberration and lateral chromatic aberration.Axial chromatic aberration (LongitudinalorAxialChromaticAberration) is called for short LCA, describes the difference of two kinds of countershaft upper objective point imaging positions of coloured light, causes the out of focus of retina image-forming; Lateral chromatic aberration (TransverseorLateralChromaticAberration) is called for short TCA, mainly caused by the dispersion properties of opthalmic optics's system own, in retina image-forming, show as the difference of image magnification ratio and the change (see Fig. 1) of space displacement.

If by the imaging system that human eye is made up of cornea, anterior chamber, iris, crystalline lens and vitreous body, regard a lens combination system as, again because object space is in kind, object space aberration is 0, can define aberration on axle is (geometric optics, aberration, optical design, Li Xiaotong, Cen Zhaofeng, Fan Shifu, in December, 2012 second edition):

${\mathrm{\δl}}_{ch,k}^{\′}=\frac{1}{n_K^{\′}{u}_K^2}{\mathrm{\Σc}}_I$

Wherein Σ C ₁for chromatic aberration coefficient on elementary axle, be also defined as the first aberration and number; N ' _kfor the refractive index of different ingredient, u _kit is then the angle of visual field of every part.

Similar, lateral chromatic aberration can be defined as:

${\mathrm{\δy}}_{ch}^{\′}=-\frac{1}{n_K^{\′}{u}_K^{\′}}{\mathrm{\Σc}}_{II}$

Wherein Σ C _Πfor elementary lateral chromatic aberration coefficient, be also defined as the second aberration and number.As can be seen from the formula of lateral chromatic aberration, elementary lateral chromatic aberration is only proportional with the first power of visual field, shows that optical system is when visual field is little, just has the adverse effect of lateral chromatic aberration.

Monochromatic spherical wave (or plane wave), after optical system, will deform due to aberration.If secondary color during object space spherical wave, so assorted corrugated after system, by because of the difference of respective aberration and distortion in various degree.And the bias between two light wave faces of different wave length, can be used to characterize aberration, be referred to as wavefront chromatic aberration.According to custom, axial chromatic aberration generally uses focal power as unit, and lateral chromatic aberration then adopts angle as unit.

From twentieth century forties, someone has carried out the research of human eye chromatism measurement, it is 3.2D (GeorgeWald that the people such as GeorgeWald adopt the measurement of spectrum stigmatoscope to obtain 14 human eyes at the LCA of 365nm to 750nm wave band, DonaldR, Griffin.May1947, Vol.37, No.5:321 ~ 336).Until today, the research of chromatism measurement never stopped, the method of chromatism measurement can be divided into the direct method of measurement and the indirect method of measurement, wherein the direct method of measurement develops into objective measurement more accurately and fast by subjective measurement, and indirect inspection rule carries out simulation study by software foundation simulation human eye.

If divide according to aberration kind, be namely divided into axial chromatic aberration and lateral chromatic aberration.Axial chromatic aberration achieves measurement, by the zernike polynomial of different wavelengths of light the 4th out of focus term coefficient being subtracted each other and can obtain axial chromatic aberration along with the development of Hartmann's human eye aberration technology.

2008, the people such as SilvestreManzanera adopted Hartmann wave front sensor to carry out objective measurement to human eye LCA.(Awavelengthtunablewavefrontsensorforthehumaneye.Silvestr eManzanera, CarmenCanovas, PedroM.Prieto.etal.OPTICSEXPRESS.26May2008.Vol.16, No.11:7748 ~ 7755) the method specifically have employed an Xe white light and an interference filter for wavelength chooses as light source, a Hartmann wave front sensor is used for the collection of human eye wavefront information, then adopts a movable zoom modules to adapt to the adjustment of wavelength shift focal length.This research method does not realize the measurement of human eye lateral chromatic aberration.

For the measurement of lateral chromatic aberration, 1987, YoumayU.Ogboso and HaroldE.Bedell by double-colored sighting target method from subjective measurement lateral chromatic aberration (Magnitudeoflateralchromaticaberrationacrosstheretinaofth ehumaneye.YoumayU.Ogboso, HaroldE.Bedell.OpticalSocietyofAmerica.1987.August.Vol.4, No.8.1666 ~ 1672).2012, WolfM.Harmening passed through the side-play amount between the fundus imaging figure of different wavelengths of light, objective measurement lateral chromatic aberration, and compares with subjective method, demonstrates accuracy.(Measurementandcorrectionoftransversechromaticoffsetsform ulti-wavelengthretinalmicroscopyinthelivingeye.WolfM.Har mening, PavanTiruveedhula, AustinRoorda.BIOMEDICALOPTICSEXPRESS.2012september.Vol.3, No.9.2066 ~ 2077) 2013 years, the people such as Raofeng in its patent (based on the human eye color difference measuring device of Hartmann sensor, Authorization Notice No.: CN103230254A) in propose the another kind of method adopting Hartmann to measure human eye aberration, timesharing can measure the lateral chromatic aberration of human eye and axial chromatic aberration.The method adopts alternately luminous monochromatic light light source, is measured the wavefront information of each wavelength by a Hartmann wave front sensor timesharing, then by calculating the aberration of human eye.The method has weak point:

1, in the monochromatic phase difference measurements of the Hartmann of reality, under fixation status, living human eye self inevitably has the existence (RalfEngbert of the tremor that trembles, micro-gaze swept microsaccade and offset d rift, ReinholdKliegl.VisionResearch.432003:1035 – 1045), these retinas are shaken micro-(or rib) mirror glazed thread making pupil corresponding and are changed, likely affect the accuracy of lateral chromatic aberration, must pay attention to.

In the shake of these fixation retinas, tremor amplitude that is irregular, altofrequency (50 ~ 100Hz) is minimum, is about cone cell diameter, only about 20 seconds visual angles; Micro-gaze swept speed a few minutes visual angle about per second; The skew formed of moving by trembling in a large number can reach 6 points of visual angles, is curvilinear motion slowly.Known micro-gaze swept is the main cause causing retina to shake.Meanwhile, the dynamic change of the aberration of human eye inherence also brings impact to measurement.

2, because the range of Hartmann limits, possibly cannot realize perfect retina for ametropic human eye and focus on, cause measurement result inaccurate.

Summary of the invention

Instant invention overcomes the deficiency of current Hartmann's chromatism measurement system, a kind of human eye chromatism measurement system based on Hartmann wave front sensor is provided, it is the optical instrument that a kind of human eye lateral chromatic aberration and axial chromatic aberration can be measured simultaneously, be intended to the measurement realizing human eye two kinds of aberration (lateral chromatic aberration, axial chromatic aberration) accurately, thus for fundus imaging diagnosis ophthalmic diseases and sick eye treatment provide more reliable data.The data acquisition while of being carried out three wavelength light by three Hartmann wave front sensors, is avoided the error that retina is shaken and human eye aberration dynamic change in time causes, simplifies experiment; By adding trial lens trial before human eye, precorrection being carried out to ametropic tested human eye, and adds defocusing compensation compensating system in systems in which.

The technical solution used in the present invention is: Hartmann's human eye chromatism measurement system, comprises the visible ray or near infrared light beacon that can focus in advance, diaphragm, first spectroscope, living human eye, focusing system, the second spectroscope, bore matching system, first wave filter, the second wave filter, the second reflecting mirror, three Hartmann wave front sensors, object observing system and computer composition; The visible ray that can focus in advance or near infrared light beacon comprise first wave length beacon, second wave length beacon, the 3rd wavelength beacon, the first reflecting mirror, the first light combination mirror and the second light combination mirror; Three Hartmann wave front sensors are the first Hartmann wave front sensor, the second Hartmann wave front sensor and the 3rd Hartmann wave front sensor;

The first wave length beacon of visible ray or near infrared light three wavelength beacon sends beacon beam, after beacon beam collimates in advance, reflected by the second light combination mirror after the first light combination mirror transmission arrives the second light combination mirror again after the first reflecting mirror reflection, the second wave length beacon of visible ray or near infrared light three wavelength beacon sends beacon beam, after beacon beam collimates in advance, reflected by the second light combination mirror arrive the second light combination mirror after the first light combination mirror reflection after, 3rd wavelength beacon of visible ray or near infrared light three wavelength beacon sends beacon beam, after beacon beam collimates in advance, through the second light combination mirror transmission, three beams light wave is pooled a branch of incoherent discrete light by this second light combination mirror, through diaphragm, first dichroic mirror enters human eye pupil, the irreflexive rear orientation light of human eye eye ground, by the first spectroscope, focusing system, second spectroscope, through bore matching system, first wave filter is selected first wave length Transmission light and is entered the first Hartmann wave front sensor, in like manner, by the remaining two-beam of the first filter reflection, second wave length luminous reflectance is selected to the second Hartmann wave front sensor through the second wave filter, last a branch of light transmission second wave filter is reflected by the second reflecting mirror, enter the 3rd Hartmann wave front sensor, the light spot image collected is delivered to computer by three Hartmann wave front sensors, computer is converted into zernike polynomial according to the three wavelength people glances differences recorded through control software design, human eye axial chromatic aberration is calculated by the difference of each wavelength zernike polynomial coefficient Section 4 (i.e. out of focus), by each wavelength each lenticule at corresponding Hartmann wave front sensor or the position deviation of prism or certain several lenticule or prism region, the partial lateral color calculating corresponding pupil position is poor,

By changing the position of object observing system, allow human eye initiatively carry out the rotation of eyeball, thus change the angle of the optical axis and measurement axis, poor for people's wink of measuring under different optical axis angle; By movable focusing system, the focusing before coordinating object observing system to measure.

Wherein, described visible ray or near infrared light three wavelength beacon are the synergistic effects considering the combination of multiple discrete wavelength, incident human eye simultaneously, meet eye-safe dosage, can be visible ray, near infrared laser, or visible ray, near-infrared semiconductor laser, or visible ray, near-infrared superradiance semiconductor device.

Wherein, three described Hartmann wave front sensors realize the wave front data simultaneously gathering different wave length.

Wherein, described partial lateral chromatism measurement, or can select certain several lenticule of closing on or prism to reduce or expand the pupil subrange of each measurement by the unit number of increase and decrease lenticule or prism array.

Wherein, three described Hartmann wave front sensors are all the Hartmann wave front sensors based on microprism array, or based on the Hartmann wave front sensor of microlens array.

Wherein, described focusing system can be double lens 4F system, a Badal focusing system, for the larger out of focus that bucking-out system cannot be measured.

The present invention is compared with prior art advantageously:

1, measure while present invention achieves human eye axial chromatic aberration and lateral chromatic aberration, and be objective measurement approach, do not need the measured to undergo training;

2, the present invention adopts three Hartmanns to measure the aberration of human eye of different wave length simultaneously, overcomes micro-gaze swept, human eye aberration fluctuates the experimental error brought, and namely avoids the error that time factor brings.

3, the present invention has focusing system, can compensate the larger out of focus that Hartmann cannot measure.

Accompanying drawing explanation

Fig. 1 is the notional axial chromatic aberration of geometric optics and lateral chromatic aberration schematic diagram;

In figure, dotted line and solid line represent the two color light of different wave length respectively, the picture left above is the axial chromatic aberration of image space, top right plot is the axial chromatic aberration of object space, and lower-left figure is the lateral chromatic aberration of a certain pupil position image space, and bottom-right graph is the lateral chromatic aberration of a certain pupil position object space;

Fig. 2 is three Hartmann's human eye chromatism measurement system structure schematic diagrams;

In figure 1, 3, the 5 first wave length beacons of visible or near infrared light three wavelength beacon for focusing in advance, second wave length beacon, 3rd wavelength beacon, 2 is the first reflecting mirror, 4 is the first light combination mirror, 6 is the second light combination mirror, 7 is diaphragm, 8 is the first spectroscope, 9 is living human eye, 10 is focusing system, 11 is the second spectroscope, 12 is bore matching system, 13 is the first wave filter, 15 is the second wave filter, 17 is the second reflecting mirror, 14, 16, 18 is three Hartmann wave front sensors, i.e. the first Hartmann wave front sensor 14, second Hartmann wave front sensor 16, 3rd Hartmann wave front sensor 18, 19 is that object observing system and 20 is for computer,

Fig. 3 is Hartmann wave front sensor microlens array, and the beams converge of a certain micro lens is to CCD face schematic diagram;

In figure, solid line and dotted line represent the two-beam that wavelength is different respectively, the light of solid dot and the hollow dots corresponding solid line of difference and dotted line, left figure is two bundle different wavelengths of light deviations in the Y direction, and right figure is left view, visible two restraint different wavelengths of light at X, the deviation in Y-direction.

Detailed description of the invention

The present invention is introduced in detail below in conjunction with the drawings and the specific embodiments.

As shown in Figure 2, a kind of Hartmann's human eye of the present invention chromatism measurement system comprises the visible ray or near infrared light beacon that can focus in advance, diaphragm 7, first spectroscope 8, living human eye 9, focusing system 10, the second spectroscope 11, bore matching system 12, first wave filter 13, second wave filter 15, second reflecting mirror 17, three Hartmann wave front sensors 14,16,18, object observing system 19 and computers 20.The visible ray that can focus in advance or near infrared light beacon comprise first wave length beacon 1, second wave length beacon 3,3rd wavelength beacon 5, first reflecting mirror 2, first light combination mirror 4 and the second light combination mirror 6, wherein visible or near infrared light beacon can be laser instrument laser, semiconductor laser laserdiode and superradiance semiconductor device superluminescentdiode-SLD; First, second, third Hartmann wave front sensor 14,16,18 can be the Hartmann wave front sensor based on microprism array, or based on the Hartmann wave front sensor of microlens array; Light combination mirror, wave filter can be heat mirror, Cold Mirrors or dichroic filter; Spectroscope can be glass spectroscope, thin film spectroscope; Focusing system can be double lens 4F system, a Badal focusing system.

Hartmann's human eye chromatism measurement system work process of this example is as follows: the first wave length beacon 1 of visible or Three-wavelengths in near-infrared beacon, second wave length beacon 3, the 3rd wavelength beacon 5 send beacon beam, after beacon beam collimates in advance, through the first reflecting mirror 2, first light combination mirror 4, second light combination mirror 6, three beams light wave is pooled a branch of incoherent discrete light, enters human eye 9 pupil through the reflection of diaphragm 7, first spectroscope 8, the irreflexive rear orientation light of human eye 9 eye ground, by the first spectroscope 8, focusing system 10, second spectroscope 11, through bore matching system 12, select first wave length Transmission light by the first wave filter 13 and enter the first Hartmann 14, in like manner, the remaining two-beam reflected by the first wave filter 13, second wave length luminous reflectance is selected to the second Hartmann 16 through the second wave filter 15, last a branch of light transmission second wave filter 15 is reflected by the second reflecting mirror 17, enter the 3rd Hartmann 18, the light spot image collected is delivered to computer 20 by three Hartmanns, computer 20 is converted into zernike polynomial according to the three wavelength people glances differences recorded through control software design, human eye axial chromatic aberration is calculated by the difference of each wavelength zernike polynomial coefficient Section 4 (out of focus), by each wavelength each lenticule (or prism) at corresponding Hartmann wave front sensor or the position deviation in certain several lenticule (or prism) region, calculate the lateral chromatic aberration of corresponding pupil position.By changing the position of object observing system 19, human eye 9 is allowed initiatively to carry out the rotation of eyeball, thus the angle of the change optical axis and measurement axis, poor for measuring the color of human eye 9 under different optical axis angle; By movable focusing system 10, the focusing before coordinating object observing system 19 to measure.

When tested wavefront is for circle territory wavefront, one group of zernike polynomial usually can be adopted to describe:

$\mathrm{\φ}(x,y)=a_0+\underset{k=1}{\overset{n}{\Σ}}{a}_k{Z}_k(x,y)---\left(1\right)$

In formula, for (before namely comprising the reflecting light of human eye aberration information) before the incident light wave of Hartmann wave front sensor, a ₀for average bit phase corrugated; a _kfor kth item zernike polynomial coefficient; Z _kfor kth item zernike polynomial.

Zernike polynomial is one group of multinomial orthogonal on circle territory, and it is defined as on unit circle:

$Z_k=\left\{\begin{array}{c}\left.\begin{array}{c}\sqrt{2(n+1)}{R}_n^m\left(\mathrm{\ρ}\right)cos\left(m\mathrm{\θ}\right)......k=odd\\ \sqrt{2(n+1)}{R}_n^m\left(\mathrm{\ρ}\right)\sin \left(m\mathrm{\θ}\right)......k=even\end{array}\right\}\mathrm{......}m\≠0\\ \sqrt{n+1}{R}_n^m\left(\mathrm{\ρ}\right).......................................m=0\end{array}\right.---\left(2\right)$

Wherein,

$R_n^m\left(\mathrm{\ρ}\right)=\underset{s=0}{\overset{(n-m)/2}{\Σ}}\frac{{(-1)}^s(n-s)!}{s!(\frac{n+m}{2}-s)!(\frac{n-m}{2}-s)!}{\mathrm{\ρ}}^{n-2s}---\left(3\right)$

θ representation unit circle different angles, m and n is respectively angle frequency and radial frequency, and their perseverances are integer and meet:

m≤n，n-|m|＝even(4)

First, second, third Hartmann wave front sensor 14,16,18 can be the Hartmann wave front sensor based on microprism array, also can be the Hartmann wave front sensor based on microlens array, both differences mainly in the mode gathering wavefront information, but are consistent (as Fig. 2) to the processing procedure of the wavefront information collected.In the facula deviation information that microprism or microlens array focal plane collect, by the process of computer, adopt centroid algorithm, suppose that the position of hot spot is for (x _i, y _i), then the wave surface error information of the full aperture detected can be expressed as:

$x_i=\frac{\underset{m=1}{\overset{M}{\Σ}}\underset{n=1}{\overset{N}{\Σ}}{x}_{nm}{I}_{nm}}{\underset{m=1}{\overset{M}{\Σ}}\underset{n=1}{\overset{N}{\Σ}}{I}_{nm}}---\left(5\right)$

$y_i=\frac{\underset{m=1}{\overset{M}{\Σ}}\underset{n=1}{\overset{N}{\Σ}}{y}_{nm}{I}_{nm}}{\underset{m=1}{\overset{M}{\Σ}}\underset{n=1}{\overset{N}{\Σ}}{I}_{nm}}---\left(6\right)$

In formula, m=1 ~ M, n=1 ~ N is that sub-aperture is mapped to pixel region corresponding on CCD photosensitive target surface, M and N is respectively the horizontal and vertical pixel count that sub-aperture is mapped to corresponding region on photosensitive target surface, I _nmthe signal that on CCD photosensitive target surface, (n, m) individual pixel-by-pixel basis receives, x _nm, y _nmbe respectively x coordinate and the y coordinate of (n, m) individual pixel.

Again according to the wavefront slope G of following formulae discovery incident wavefront _x, G _y:

$G_x=\frac{1}{s}\·\underset{s}{\∫\∫}\frac{\∂\mathrm{\Φ}(x,y)}{\∂x}dxdy=\frac{\mathrm{\Δ}x}{f}---\left(7\right)$

$G_y=\frac{1}{s}\·\underset{s}{\∫\∫}\frac{\∂\mathrm{\Φ}(x,y)}{\∂y}dxdy=\frac{\mathrm{\Δ}y}{f}---\left(8\right)$

In formula, s is sub-aperture area; Φ (x, y) is incident beam Wave-front phase; F is lenticule focal length.

Aberration wave-front conversion is the zernike polynomial that can be used for calculating, and a complete wavefront Φ (x, y) can describe with zernike polynomial (1).The pass of the slope data in sub-aperture and zernike polynomial coefficient is:

$\left\{\begin{array}{c}{G}_X\left(i\right)=\underset{k=1}{\overset{n}{\Σ}}{a}_k\frac{\underset{S_i}{\∫\∫}\frac{\∂Z_k(x,y)}{\∂x}dxdy}{S_i}+{\mathrm{\ϵ}}_x=\underset{k=1}{\overset{n}{\Σ}}{a}_k{Z}_{xk}\left(i\right)+{\mathrm{\ϵ}}_x\\ G_Y\left(i\right)=\underset{k=1}{\overset{n}{\Σ}}{a}_k\frac{\underset{S_i}{\∫\∫}\frac{\∂Z_k(x,y)}{\∂y}dxdy}{S_i}+{\mathrm{\ϵ}}_y=\underset{k=1}{\overset{n}{\Σ}}{a}_k{Z}_{yk}\left(i\right)+{\mathrm{\ϵ}}_y\end{array}\right.---\left(9\right)$

Wherein ε _x, ε _yfor Wave-front phase measurement error, n is pattern exponent number, Z _xk(i) and Z _yki () is the G-bar of kth item zernike polynomial in the i-th sub-aperture, S _ifor the normalized area of sub-aperture.The relation of m sub-aperture slope n item zernike coefficient is expressed in matrix as:

$\left[\begin{array}{c}{G}_x\left(1\right)\\ G_y\left(1\right)\\ G_x\left(2\right)\\ G_y\left(2\right)\\ \mathrm{...}\\ G_x\left(m\right)\\ G_x\left(m\right)\end{array}\right]=\left[\begin{array}{cccc}{Z}_{x1}\left(1\right)& Z_{x2}\left(1\right)& \mathrm{...}& Z_{xn}\left(1\right)\\ Z_{y1}\left(1\right)& Z_{y2}\left(1\right)& \mathrm{...}& Z_{yn}\left(1\right)\\ Z_{x1}\left(2\right)& Z_{x2}\left(2\right)& \mathrm{...}& Z_{yn}\left(2\right)\\ Z_{y1}\left(2\right)& Z_{y2}\left(2\right)& \mathrm{...}& Z_{yn}\left(2\right)\\ \mathrm{...}& \mathrm{...}& \mathrm{...}& \mathrm{...}\\ Z_{x1}\left(m\right)& Z_{x2}\left(m\right)& \mathrm{...}& Z_{xn}\left(m\right)\\ Z_{y1}\left(m\right)& Z_{y2}\left(m\right)& \mathrm{...}& Z_{yn}\left(m\right)\end{array}\right]\left[\begin{array}{c}{a}_1\\ a_2\\ \mathrm{...}\\ a_n\end{array}\right]+\left[\begin{array}{c}{\mathrm{\ϵ}}_1\\ {\mathrm{\ϵ}}_2\\ {\mathrm{\ϵ}}_3\\ {\mathrm{\ϵ}}_4\\ \mathrm{...}\\ {\mathrm{\ϵ}}_{2m-1}\\ {\mathrm{\ϵ}}_{2m}\end{array}\right]---\left(10\right)$

Be designated as:

G＝DA+ε(11)

For arbitrary 2m and n, the least square of above-mentioned equation and least-norm solution can use generalized inverse D ⁺represent:

A＝D ⁺G(12)

Now obtain zernike coefficient A.

Zernike coefficient A C _nrepresent, wherein n represents zernike coefficient n-th.

The difference in the popin face of the different wave length simulated by wavefront, can obtain the wavefront chromatic aberration between different wave length.

The process being solved axial chromatic aberration by zernike coefficient A is as follows:

Y-direction and X-direction astigmatism item C ₃, C ₅, the angle of astigmatism can be calculated:

$\mathrm{\α}=0.5\×\arctan \left(\frac{C_3}{C_5}\right)---\left(13\right)$

By calculating two intermediate variable B and E, wherein C ₄for out of focus item:

$B=\frac{C_3\×2\sqrt{6}}{\sin \left(2\mathrm{\α}\right)}$ or $B=-\frac{C_3\×2\sqrt{6}}{\sin \left(2\mathrm{\α}\right)}---\left(14\right)$

$E=2\sqrt{3}{C}_4-\frac{B}{2}---\left(15\right)$

By (11), two wavelength X 1 of (12) calculating in units of diopter, the axial chromatic aberration of λ 2, wherein R is pupil radium, for the E intermediate variable of λ 1, e intermediate variable for λ 2:

Lateral chromatic aberration process following (below for a certain lenticule) is solved by the bias of each wavelength in each lenticule of lenticule or prism array or prism or certain several lenticule or prism region:

Each lenticular radius of known a certain microlens array is r, and focal length is f, and wavelength X 1 converges at this lenticule region (x ₁, y ₁), wavelength X 2 converges at (x ₂, y ₂), 2 wavelengths points are Δ x in X-direction distance, and distance is Δ y in the Y direction, then can obtain the partial lateral aberration β in X, Y both direction that this lenticule corresponds to human eye pupil position _y, β _xfor:

${\mathrm{\β}}_y=\frac{r-y_1}{f}R-\frac{r-y_2}{f}R=\frac{\mathrm{\Δ}y}{f}R---\left(17\right)$

${\mathrm{\β}}_x=\frac{r-x_1}{f}R-\frac{r-x_2}{f}R=\frac{\mathrm{\Δ}x}{f}R---\left(18\right).$

Claims (6)

1. Hartmann's human eye chromatism measurement system, it is characterized in that: comprise the visible ray or near infrared light beacon that can focus in advance, diaphragm (7), first spectroscope (8), living human eye (9), focusing system (10), second spectroscope (11), bore matching system (12), first wave filter (13), the second wave filter (15), the second reflecting mirror (17), three Hartmann wave front sensors (14,16,18), object observing system (19) and computer (20) composition; The visible ray that can focus in advance or near infrared light beacon comprise first wave length beacon (1), second wave length beacon (3), 3rd wavelength beacon (5), first reflecting mirror (2), the first light combination mirror (4) and the second light combination mirror (6); Three Hartmann wave front sensors (14,16,18) are the first Hartmann wave front sensor (14), the second Hartmann wave front sensor (16) and the 3rd Hartmann wave front sensor (18);

The first wave length beacon (1) of visible ray or near infrared light three wavelength beacon sends beacon beam, after beacon beam collimates in advance, arrive after the second light combination mirror (6) through the first light combination mirror (4) transmission again after the first reflecting mirror (2) reflection and reflected by the second light combination mirror (6), the second wave length beacon (3) of visible ray or near infrared light three wavelength beacon sends beacon beam, after beacon beam collimates in advance, reflected by the second light combination mirror (6) arrive the second light combination mirror (6) after the first light combination mirror (4) reflection after, 3rd wavelength beacon (5) of visible ray or near infrared light three wavelength beacon sends beacon beam, after beacon beam collimates in advance, through the second light combination mirror (6) transmission, three beams light wave is pooled a branch of incoherent discrete light by this second light combination mirror (6), through diaphragm (7), first spectroscope (8) reflection enters human eye (9) pupil, the irreflexive rear orientation light of human eye (9) eye ground, by the first spectroscope (8), focusing system (10), second spectroscope (11), through bore matching system (12), first wave filter (13) is selected first wave length Transmission light and is entered the first Hartmann wave front sensor (14), in like manner, the remaining two-beam reflected by the first wave filter (13), second wave length luminous reflectance is selected to the second Hartmann wave front sensor (16) through the second wave filter (15), last a branch of light transmission second wave filter (15) is reflected by the second reflecting mirror (17), enter the 3rd Hartmann wave front sensor (18), three Hartmann wave front sensors (14, 16, 18) light spot image collected is delivered to computer (20), computer (20) is converted into zernike polynomial according to the three wavelength people glances differences recorded through control software design, human eye axial chromatic aberration is calculated by the difference of each wavelength zernike polynomial coefficient Section 4 (i.e. out of focus), by each wavelength each lenticule at corresponding Hartmann wave front sensor or the position deviation of prism or certain several lenticule or prism region, the partial lateral color calculating corresponding pupil position is poor,

By changing the position of object observing system (19), allow human eye (9) initiatively carry out the rotation of eyeball, thus change the angle of the optical axis and measurement axis, poor for human eye (9) color measured under different optical axis angle; By movable focusing system (10), the focusing before coordinating object observing system (19) to measure.

2. Hartmann's human eye chromatism measurement system according to claim 1, it is characterized in that: described three wavelength beacons (1,3,5) are the synergistic effects considering the combination of multiple discrete wavelength, incident human eye simultaneously, meet eye-safe dosage, can be visible ray, near infrared laser, or visible ray, near-infrared semiconductor laser, or visible ray, near-infrared superradiance semiconductor device.

3. Hartmann's human eye chromatism measurement system according to claim 1, is characterized in that: described three Hartmann wave front sensors (14,16,18) realize the wave front data simultaneously gathering different wave length.

4. Hartmann's human eye chromatism measurement system according to claim 1, it is characterized in that: described partial lateral chromatism measurement, or certain several lenticule of closing on or prism can be selected to reduce or expands the pupil subrange of each measurement by the unit number of increase and decrease lenticule or prism array.

5. Hartmann's human eye chromatism measurement system according to claim 1, it is characterized in that: described three Hartmann wave front sensors (14,16,18) are all the Hartmann wave front sensors based on microprism array, or based on the Hartmann wave front sensor of microlens array.

6. Hartmann's human eye chromatism measurement system according to claim 1, is characterized in that: described focusing system (10) can be double lens 4F system, a Badal focusing system, for the larger out of focus that bucking-out system cannot be measured.