CN105865638A - Calibration device and method for frequency response characteristic of Shack-Hartmann wave-front sensor - Google Patents

Abstract

The invention relates to a calibration device and method for the frequency response characteristic of a Shack-Hartmann wave-front sensor (hereinafter referred to as a sensor). The device comprises a knife edge, a precise knife edge position adjusting device and a collimating mirror and the sensor which are arranged on an output light path of a laser device in sequence; the optical axis of the sensor and the optical axis of the collimating mirror are well penetrated; the line direction of a microlens array of the sensor is perpendicular to an XOZ plane of a space rectangular coordinate system, and the column direction is parallel to the OX axis of the rectangular coordinate system. The knife edge is mounted on the precise knife edge position adjusting device, the distance between the knife edge and the plane where the microlens array is located is smaller than Lx/Lambda vmax, vmax is cut-off frequency of the sensor, Lx is the work length of the sensor in the X direction, and Lambda is the wavelength of laser output by the laser device; edges of the knife edge are parallel to the line direction of the microlens array, the edges are located below the microlens array, and the extension lines of the edges along the optical axis of the collimating mirror intersect to the center of the line of lenses at the lowest position of the microlens array. By means of the calibration device and method, the response characteristic of the sensor on the full-band can be obtained.

Description

The caliberating device of Shack-Hartmann wavefront sensor Frequency Response and scaling method

Technical field

The invention belongs to optical field, relate to the demarcation dress of a kind of Shack-Hartmann wavefront sensor frequency response characteristic Put and scaling method.

Background technology

Shack-Hartmann wavefront sensor is mainly made up of microlens array and detector, in optical element and optical system The fields such as system wave aberration test, light laser parameter diagnosis and control, atmospheric turbulance parameter measurement, human eye aberration measurement have extensively should With.Shack-Hartmann wavefront sensor is less demanding to the temporal coherence of light source, has simple in construction, easily operated, ring The advantages such as border strong adaptability, real-time are good, dynamic range is big.

At present, the scaling method of Shack-Hartmann wavefront sensor frequency response characteristic is the phase place making different frequency Plate, irradiates phase-plate with monochromatic collimated beam ripple, Shack-Hartmann wavefront sensor measure the outgoing light wave of phase-plate, thus Obtain Shack-Hartmann wavefront sensor response characteristic at corresponding frequencies.But, current technology level there is no method and protects Card high-frequency phase plate machining accuracy, and processing different frequency phase-plate costly, phase-plate method cannot obtain Shack- Hartmann wave front sensor is in the response characteristic of full frequency band.

Summary of the invention

According to background above, the invention provides the caliberating device of a kind of Shack-Hartmann wavefront sensor Frequency Response And scaling method, this caliberating device and scaling method can obtain the Shack-Hartmann wavefront sensor response spy at full frequency band Property.

The present invention based on diffraction theory, utilize laser instrument and the edge of a knife produce light intensity, phase place spatial frequency all along Shack-Kazakhstan Special graceful Wavefront sensor column direction continually varying diffracted wave, it is achieved Shack-Hartmann wavefront sensor frequency response characteristic Demarcate.Particularly as follows: realize its right with monochromatic collimated beam source first with the locating module of Shack-Hartmann wavefront sensor Accurate；Move edge of a knife place locating module again, make edge of a knife sword edge direction be parallel to the line direction of Wavefront sensor detector, directional light Ripple through knife edge diffraction produce light intensity, phase place spatial frequency all continuous along Shack-Hartmann wavefront sensor detector column direction The diffracted wave of change；Finally Shack-Hartmann wavefront sensor Frequency Response is demarcated.

The technical scheme is that

The caliberating device of Shack-Hartmann wavefront sensor Frequency Response, including laser instrument, collimating mirror and Shack-Kazakhstan Special graceful Wavefront sensor；Described collimating mirror and Shack-Hartmann wavefront sensor are successively set on the output light path of laser instrument On；The optical axis of described Shack-Hartmann wavefront sensor and collimating mirror is put on；Described Shack-Hartmann wavefront sensor bag Include microlens array；The line direction of described microlens array is perpendicular to the XOZ plane of rectangular coordinate system in space, and column direction is parallel to The OX axle of rectangular coordinate system in space；It is characterized in that caliberating device also includes the edge of a knife and knife-edge positions device for precisely regulating； The described edge of a knife is arranged on knife-edge positions device for precisely regulating, and between collimating mirror and Shack-Hartmann wavefront sensor Light path on；Timing signal, the edge of a knife distance away from microlens array place plane is less than L_x/(λv_max), v_maxFor Shack-Hartmann The cut-off frequency of Wavefront sensor, L_xFor Shack-Hartmann wavefront sensor active length in the X direction, λ is described sharp The wavelength of light device Output of laser；The sword limit of the edge of a knife is parallel with the line direction of described microlens array, the entrance pupil of sword back gauge collimating mirror Edge has certain distance, sword limit to be positioned at below microlens array, and the extended line of sword edge collimating mirror optical axis direction meets at lenticule The center of array bottom a line lens；Outgoing collimated light beam after the collimated mirror of monochromatic light that described laser instrument sends, described Collimated light beam is after the sword limit diffraction of the edge of a knife, and the dead ahead at microlens array produces for Shack-Hartmann wavefront sensor The diffraction light wave phase distribution that Frequency Response is demarcated, and the spatial frequency of the phase place of this diffraction light wave is at Shack-Hartmann wavefront On sensor column direction linearly increasing.

Above-mentioned knife-edge positions device for precisely regulating is made up of automatically controlled turntable and D translation platform, and the edge of a knife is arranged on automatically controlled turntable On, export wave front data in real time in conjunction with Shack-Hartmann wavefront sensor, it is achieved being automatically adjusted of knife-edge positions.

The scaling method one of Shack-Hartmann wavefront sensor Frequency Response, it is characterized in that and includes following step Rapid:

1] open laser instrument, adjust the position of Shack-Hartmann wavefront sensor so that it is export with being arranged on laser instrument Collimating mirror in light path is put on；

2] adjust the position of the edge of a knife, make the sword edge direction of the edge of a knife and the microlens array of Shack-Hartmann wavefront sensor Line direction parallel；

3] edge of a knife is cut in the light path between collimating mirror and Shack-Hartmann wavefront sensor, and make the edge of a knife away from described micro- The distance of lens arra place plane is less than L_x/(λv_max), sword limit is positioned at below microlens array, collimating mirror optical axis side, sword edge To extended line meet at the center of microlens array bottom a line lens；Described v_maxFor Shack-Hartmann wavefront sensing The cut-off frequency of device, L_xFor Shack-Hartmann wavefront sensor active length in the X direction, λ is the output of described laser instrument The wavelength of laser；

4] by step 3] device is adjusted after, at the dead ahead of described microlens array, generation is used for the diffraction demarcated Phase of light wave is distributed, and utilizes Shack-Hartmann wavefront sensor to obtain the wave front data of described diffraction light wave phase distribution, then Response characteristic F of different frequency wavefront is by Shack-Hartmann wavefront sensor:

$F=\frac{FFT\left(W_{test}\right)}{FFT\left(W_{theory}\right)}$

In formula, FFT represents Fourier transformation；W_testActual wavefront number measured by Shack-Hartmann wavefront sensor According to；W_theoryFor theoretical wavefront data.

Above-mentioned steps 2] particularly as follows:

2.1 positions adjusting the edge of a knife；

2.2 calculateIn formula, w_i,jThe i-th row jth row lenticule pair for microlens array The wave front data answered；For the meansigma methods of the i-th row lenticule correspondence wave front data of microlens array,

If 2.3 Δs are more than setting threshold value, then the sword edge direction of the edge of a knife and the lenticule of Shack-Hartmann wavefront sensor The line direction of array is not parallel, repeats step 2.1～2.3；If Δ less than or equal to set threshold value, then the sword edge direction of the edge of a knife with The line direction of the microlens array of Shack-Hartmann wavefront sensor is parallel.

The scaling method two of Shack-Hartmann wavefront sensor Frequency Response, it is characterized in that and includes following step Rapid:

1] open laser instrument, adjust the position of Shack-Hartmann wavefront sensor so that it is export with being arranged on laser instrument Collimating mirror in light path is put on；

2] edge of a knife is cut in the light path between collimating mirror and Shack-Hartmann wavefront sensor, and make the edge of a knife away from described micro- The distance of lens arra place plane is less than L_x/(λv_max), sword limit is positioned at below microlens array, collimating mirror optical axis side, sword edge To extended line meet at the center of microlens array bottom a line lens；Described v_maxFor Shack-Hartmann wavefront sensing The cut-off frequency of device, L_xFor Shack-Hartmann wavefront sensor active length in the X direction, λ is the output of described laser instrument The wavelength of laser；

3] adjust the position of the edge of a knife, make the sword edge direction of the edge of a knife and the microlens array of Shack-Hartmann wavefront sensor Line direction parallel；

4] by step 3] device is adjusted after, at the dead ahead of described microlens array, generation is used for the diffraction demarcated Phase of light wave is distributed, and utilizes Shack-Hartmann wavefront sensor to obtain the wave front data of described diffraction light wave phase distribution, then Response characteristic F of different frequency wavefront is by Shack-Hartmann wavefront sensor:

$F=\frac{FFT\left(W_{test}\right)}{FFT\left(W_{theory}\right)}$

In formula, FFT represents Fourier transformation；W_testActual wavefront number measured by Shack-Hartmann wavefront sensor According to；W_theoryFor theoretical wavefront data.

Above-mentioned steps 3] particularly as follows:

3.1 positions adjusting the edge of a knife；

3.2 calculateIn formula, w_i,jThe i-th row jth row lenticule for microlens array Corresponding wave front data；For the meansigma methods of the i-th row lenticule correspondence wave front data of microlens array,

If 3.3 Δs are more than setting threshold value, then the sword edge direction of the edge of a knife and the lenticule of Shack-Hartmann wavefront sensor The line direction of array is not parallel, repeats step 3.1～3.3；If Δ less than or equal to set threshold value, then the sword edge direction of the edge of a knife with The line direction of the microlens array of Shack-Hartmann wavefront sensor is parallel.

There is advantages that

1, the present invention is based on diffraction theory, utilizes the parallel one-wavelength laser of collimating mirror outgoing, generates light through knife edge diffraction By force, the spatial frequency of phase place all continually varying diffraction along the column direction of Shack-Hartmann wavefront sensor microlens array Light wave, by contrast Shack-Hartmann wavefront sensor measured by wave front data and gross data, thus can disposably realize right The demarcation of Shack-Hartmann wavefront sensor full frequency band frequency response characteristic, the performance offer for Wavefront sensor is comprehensively sentenced Fix then.

2, the present invention utilizes knife-edge positions device for precisely regulating to achieve sword edge direction and the Shack-Hartmann ripple of the edge of a knife The high accuracy alignment of the line direction of the microlens array of front sensor, thus improve the reliability that frequency response characteristic is demarcated.

3, to calculate response time short for the present invention, and result of calculation accuracy is high.

4, present configuration is simple, stability is high, reproducible, measurement result confidence level is high.

Accompanying drawing explanation

Fig. 1 is the structural representation of the present invention；

Fig. 2 is the structural representation of the knife-edge positions device for precisely regulating of the present invention；

In figure, 1-laser instrument, 2-collimating mirror, 3-knife-edge positions device for precisely regulating, the automatically controlled turntable of 31-, 32-D translation Platform, 4-Shack-Hartmann wavefront sensor, 5-microlens array, 6-diffraction light wave phase is distributed, the 7-edge of a knife.

Detailed description of the invention

With detailed description of the invention, the present invention is elaborated below in conjunction with the accompanying drawings.

Fig. 1 show the structure of the caliberating device of Shack-Hartmann wavefront sensor Frequency Response provided by the present invention Schematic diagram, it includes laser instrument 1, collimating mirror 2, Shack-Hartmann wavefront sensor 4, knife-edge positions device for precisely regulating 3, cutter Mouth 7；Wherein, collimating mirror 2 and Shack-Hartmann wavefront sensor 4 are successively set on the output light path of laser instrument 1.

Shack-Hartmann wavefront sensor 4 includes microlens array 5, and it is straight that the line direction of microlens array is perpendicular to space The XOZ plane of angle coordinate system, column direction is parallel to the OX axle of rectangular coordinate system in space；Shack-Hartmann wavefront sensor 4 with The optical axis of collimating mirror 2 puts on (i.e. each lenticular optical axis in microlens array 5 is all parallel with the optical axis of collimating mirror 2).

Knife-edge positions device for precisely regulating 3 is made up of automatically controlled turntable 31 and D translation platform 32；The edge of a knife 7 is arranged on automatically controlled turn On platform 31, and in the light path between collimating mirror 2 and Shack-Hartmann wavefront sensor 4.Timing signal, utilizes D translation The edge of a knife 7 is cut light path by platform 32, makes sword limit and the microlens array 5 of the edge of a knife 7 by adjusting knife-edge positions device for precisely regulating 3 Line direction is parallel, and there is certain distance (being preferably maintained at least more than 5mm) at the entrance pupil edge of sword back gauge collimating mirror 2, and sword limit is positioned at micro- Below lens arra 5, the extended line of sword edge collimating mirror 2 optical axis direction meets at the center of microlens array 5 bottom row lens Place；The edge of a knife 7 distance away from microlens array 5 place plane is slightly less than L_x/(λv_max), v_maxFor Shack-Hartmann wavefront sensing The cut-off frequency of device 4, L_xFor Shack-Hartmann wavefront sensor 4 active length in the X direction.Now, the sword limit of the edge of a knife 7 Diffraction light wave phase will be completely covered the significant response frequency range of Shack-Hartmann wavefront sensor 4.

The calibration principle of the present invention is:

According to diffraction theory, monochromatic collimated beam ripple after the sword limit diffraction of the edge of a knife 7, the diffraction light at distance z in its rear Ripple has following light intensity, a PHASE DISTRIBUTION form:

$I=1-\frac{\sqrt{2}}{\mathrm{\π}\mathrm{\ϵ}}cos(\frac{{\mathrm{\π\ϵ}}^2}{2}+\frac{\mathrm{\π}}{4})---\left(1\right)$

$\mathrm{\φ}=-\frac{\sqrt{2}}{2\mathrm{\π}\mathrm{\ϵ}}sin(\frac{{\mathrm{\π\ϵ}}^2}{2}+\frac{\mathrm{\π}}{4})---\left(2\right)$

In formulaWherein λ is the wavelength of monochromatic collimated beam ripple, and x represents along X-direction lenticule away from cutter The distance on mouthful sword limit, z represents along the Z-direction microlens array place plane distance from sword limit.

The light intensity of sword limit diffraction light wave and the change frequency of PHASE DISTRIBUTION of the edge of a knife 7 be:

V=x/ (λ z) (3)

Formula (3) shows that the change frequency that Diffraction Diffraction phase of light wave is distributed is linearly increasing along X-direction, Diffraction Diffraction light Containing abundant frequency content in the wavefront signals of wave phase distribution, based on this frequency to Shack-Hartmann wavefront sensor 4 Ring characteristic to demarcate.

Outgoing collimated light beam after the collimated mirror of monochromatic light 2 that laser instrument 1 sends, this collimated light beam spreads out through the sword limit of the edge of a knife 7 After penetrating, at the dead ahead of microlens array 5, generation is used for the diffraction that Shack-Hartmann wavefront sensor 4 Frequency Response is demarcated Phase of light wave distribution 6.Shack-Hartmann wavefront sensor 4 is utilized to obtain the wave front data of diffraction light wave phase distribution 6, and right This wave front data carries out Fourier transformation；The wave front data of theoretical derivation gained diffraction light wave phase distribution is carried out in Fu simultaneously Leaf transformation, is divided by the Fourier transformation result of the two and i.e. obtains Shack-Hartmann wavefront sensor 4 to different frequency wavefront Response characteristic.

The scaling method of Shack-Hartmann wavefront sensor Frequency Response provided by the present invention, comprises the following steps: [note: the sequencing of step (2) and step (3) can exchange]

(1) open laser instrument 1, adjust the position of Shack-Hartmann wavefront sensor 4 so that it is be arranged on laser instrument 1 Collimating mirror 2 on output light path is put on.

(2), at the dotted line position being placed in Fig. 1 by knife-edge positions device for precisely regulating 3, knife-edge positions fine adjustment is controlled The automatically controlled turntable 31 of device 3, makes the sword edge direction of the edge of a knife 7 mounted thereto and the micro-of Shack-Hartmann wavefront sensor 4 The line direction of lens arra 5 is parallel.

(3) by D translation platform 32, the edge of a knife 7 is cut in light path, makes the edge of a knife 7 sword limit be positioned at below microlens array 5, And make the extended line of the edge of a knife 7 sword edge collimating mirror 2 optical axis direction meet at the center of microlens array 5 bottom row lens, make The edge of a knife 7 distance away from microlens array 5 place plane is slightly less than L_x/(λv_max), v_maxFor Shack-Hartmann wavefront sensor Cut-off frequency, L_xFor Shack-Hartmann wavefront sensor active length in the X direction.

(4), after being adjusted by device by above-mentioned steps, generation is used for the diffraction demarcated by the dead ahead at microlens array 5 Phase of light wave distribution 6；Shack-Hartmann wavefront sensor 4 is utilized to obtain the wave front data of diffraction light wave phase distribution 6, to institute The wave front data recorded carries out Fourier transformation, and the wave front data being simultaneously distributed the diffraction phase of theoretical derivation gained carries out Fu In leaf transformation, the Fourier transformation result of the two is divided by and i.e. obtains Shack-Hartmann wavefront sensor to different frequency wavefront Response characteristic, i.e.

$F=\frac{FFT\left(W_{test}\right)}{FFT\left(W_{theory}\right)}---\left(4\right)$

In formula: FFT represents Fourier transformation；W_testActual wavefront number measured by Shack-Hartmann wavefront sensor According to；W_theoryFor theoretical wavefront data.

By aforementioned formula (3) it can be seen that when sword edge direction is parallel to the line direction of microlens array 5, Shack-Kazakhstan Measured by special graceful Wavefront sensor 5, wave front data is consistent at the line direction of microlens array 5, therefore, and can in above-mentioned steps (2) The parallel degree of sword edge direction with Wavefront sensor detector row direction to be passed judgment on the edge of a knife 7 by formula (5), computing formula As follows:

$\mathrm{\Δ}=\frac{1}{M}\underset{i=1}{\overset{M}{\Σ}}\underset{j=1}{\overset{N}{\Σ}}\sqrt{\frac{{(w_{i,j}-\stackrel{\‾}{w_i})}^2}{N-1}}---\left(5\right)$

In formula, w_i,jThe i-th row jth row wave front data acquired in described Shack-Hartmann wavefront sensor,For institute State the meansigma methods of the i-th row wave front data acquired in Shack-Hartmann wavefront sensor,

Claims (6)

1. the caliberating device of Shack-Hartmann wavefront sensor Frequency Response, including laser instrument, collimating mirror and Shack-Hart Graceful Wavefront sensor；Described collimating mirror and Shack-Hartmann wavefront sensor are successively set on the output light path of laser instrument； The optical axis of described Shack-Hartmann wavefront sensor and collimating mirror is put on；Described Shack-Hartmann wavefront sensor includes micro- Lens arra；The line direction of described microlens array is perpendicular to the XOZ plane of rectangular coordinate system in space, and column direction is parallel to space The OX axle of rectangular coordinate system；It is characterized in that: caliberating device also includes the edge of a knife and knife-edge positions device for precisely regulating；

The described edge of a knife is arranged on knife-edge positions device for precisely regulating, and is positioned at collimating mirror and Shack-Hartmann wavefront sensor Between light path on；Timing signal, the described edge of a knife distance away from microlens array place plane is less than L_x/(λv_max), v_maxFor the summer Gram-cut-off frequency of Hartmann wave front sensor, L_xFor Shack-Hartmann wavefront sensor active length in the X direction, λ is the wavelength of described laser instrument Output of laser；The sword limit of the edge of a knife is parallel with the line direction of described microlens array, and sword back gauge collimates The entrance pupil edge of mirror has certain distance, sword limit to be positioned at below microlens array, and the extended line of sword edge collimating mirror optical axis direction is handed over Center in microlens array bottom a line lens；

Outgoing collimated light beam after the collimated mirror of monochromatic light that described laser instrument sends, described collimated light beam is through the sword limit diffraction of the edge of a knife After, the dead ahead at microlens array produces the diffraction light wave phase demarcated for Shack-Hartmann wavefront sensor Frequency Response Position distribution, and the spatial frequency of the phase place of this diffraction light wave is linearly increasing on Shack-Hartmann wavefront sensor column direction.

The caliberating device of Shack-Hartmann wavefront sensor Frequency Response the most according to claim 1, it is characterised in that: Described knife-edge positions device for precisely regulating is made up of automatically controlled turntable and D translation platform, and the edge of a knife is arranged on automatically controlled turntable.

3. the scaling method of Shack-Hartmann wavefront sensor Frequency Response, it is characterised in that: comprise the following steps:

1] open laser instrument, adjust Shack-Hartmann wavefront sensor position so that it is be arranged on laser instrument output light path On collimating mirror put on；

2] adjust the position of the edge of a knife, make the row of the sword edge direction of the edge of a knife and the microlens array of Shack-Hartmann wavefront sensor Direction is parallel；

3] edge of a knife is cut in the light path between collimating mirror and Shack-Hartmann wavefront sensor, and make the edge of a knife away from described lenticule The distance of array place plane is less than L_x/(λv_max), sword limit is positioned at below microlens array, sword edge collimating mirror optical axis direction Extended line meets at the center of microlens array bottom a line lens；Described v_maxFor Shack-Hartmann wavefront sensor Cut-off frequency, L_xFor Shack-Hartmann wavefront sensor active length in the X direction, λ is described laser instrument Output of laser Wavelength；

4] by step 3] device is adjusted after, at the dead ahead of described microlens array, generation is used for the diffraction light wave demarcated PHASE DISTRIBUTION, utilizes Shack-Hartmann wavefront sensor to obtain the wave front data of described diffraction light wave phase distribution, then summer Gram-response characteristic F of different frequency wavefront is by Hartmann wave front sensor:

$F=\frac{FFT\left(W_{test}\right)}{FFT\left(W_{theory}\right)}$

In formula, FFT represents Fourier transformation；W_testActual wavefront data measured by Shack-Hartmann wavefront sensor； W_theoryFor theoretical wavefront data.

The scaling method of Shack-Hartmann wavefront sensor Frequency Response the most according to claim 3, it is characterised in that: Described step 2] particularly as follows:

2.1 positions adjusting the edge of a knife；

2.2 calculateIn formula, w_i,jThe i-th row jth row lenticule pair for microlens array The wave front data answered；For the meansigma methods of the i-th row lenticule correspondence wave front data of microlens array,

If 2.3 Δs are more than setting threshold value, then the sword edge direction of the edge of a knife and the microlens array of Shack-Hartmann wavefront sensor Line direction not parallel, repeat step 2.1～2.3；If Δ is less than or equal to setting threshold value, then the sword edge direction of the edge of a knife and the summer Gram-line direction of the microlens array of Hartmann wave front sensor is parallel.

5. the scaling method of Shack-Hartmann wavefront sensor Frequency Response, it is characterised in that: comprise the following steps:

1] open laser instrument, adjust Shack-Hartmann wavefront sensor position so that it is be arranged on laser instrument output light path On collimating mirror put on；

2] edge of a knife is cut in the light path between collimating mirror and Shack-Hartmann wavefront sensor, and make the edge of a knife away from described lenticule The distance of array place plane is less than L_x/(λv_max), sword limit is positioned at below microlens array, sword edge collimating mirror optical axis direction Extended line meets at the center of microlens array bottom a line lens；Described v_maxFor Shack-Hartmann wavefront sensor Cut-off frequency, L_xFor Shack-Hartmann wavefront sensor active length in the X direction, λ is described laser instrument Output of laser Wavelength；

3] adjust the position of the edge of a knife, make the row of the sword edge direction of the edge of a knife and the microlens array of Shack-Hartmann wavefront sensor Direction is parallel；

4] by step 3] device is adjusted after, at the dead ahead of described microlens array, generation is used for the diffraction light wave demarcated PHASE DISTRIBUTION, utilizes Shack-Hartmann wavefront sensor to obtain the wave front data of described diffraction light wave phase distribution, then summer Gram-response characteristic F of different frequency wavefront is by Hartmann wave front sensor:

$F=\frac{FFT\left(W_{test}\right)}{FFT\left(W_{theory}\right)}$

In formula, FFT represents Fourier transformation；W_testActual wavefront data measured by Shack-Hartmann wavefront sensor； W_theoryFor theoretical wavefront data.

The scaling method of Shack-Hartmann wavefront sensor Frequency Response the most according to claim 5, it is characterised in that: Described step 3] particularly as follows:

3.1 positions adjusting the edge of a knife；

3.2 calculateIn formula, w_i,jThe i-th row jth row lenticule pair for microlens array The wave front data answered；For the meansigma methods of the i-th row lenticule correspondence wave front data of microlens array,

If 3.3 Δs are more than setting threshold value, then the sword edge direction of the edge of a knife and the microlens array of Shack-Hartmann wavefront sensor Line direction not parallel, repeat step 3.1～3.3；If Δ is less than or equal to setting threshold value, then the sword edge direction of the edge of a knife and the summer Gram-line direction of the microlens array of Hartmann wave front sensor is parallel.