CN102538689B - Centering and locating device of optical system and using method thereof - Google Patents

Abstract

The invention relates to a centering and locating device of an optical system and a using method of the centering and locating device. The centering and locating device comprises an internal focusing telescope, a white light fiber interferometer, an electronics part, a computer, an adjusting rack, a guide rail and an optical platform. The centering and locating device provided by the invention can simultaneously measure the center deviation, the center thickness and the center interval of an optical element in an optical assembling and debugging process, so as to center and locate the optical system; and the centering and locating device is applicable to the assembling and the debugging of horizontal optical systems or coaxial optical systems with complicated operating attitudes, such as a turning light axis and the like, and meanwhile, can be applied to the centering, locating and assembling of a rotation reflection optical system, the measurement of the center deviation and the center thickness of an optical lens, the gluing of the optical lens, and the centered edging, the precision angle measurement, the precision position measurement and the like, of the optical lens, in a popularizing manner.

Description

Optical system centering-setting device and using method thereof

Technical field

The present invention relates to optical system, particularly a kind of optical system centering-setting device and using method thereof during for optical system bulk cargo school.

Background technology

Optical centre deviation be in optical instrument foozle one larger on complete machine optics assembly quality impact, also error more rambunctious simultaneously.The existence of center of optical element deviation has destroyed the coaxiality of optical system, causes the decline of image quality.Optical centre interval error is the other important errors in optical instrument foozle, and its existence directly has influence on the imaging performance of optical system.

In the process of the dress school of optical system, precision optical system particularly, in the assembling process of projection mask aligner's object lens, aerial survey camera lens, interferometer standard lens, laserresonator chamber length, laser space communication ground validation system etc., optical centre deviation and Center Gap are had to very strict control requirement.

Therefore, at optical instrument, debug in process, how effectively to solve the centre deviation of optical element and Center Gap error is the key point that guarantees Performance of Optical System.

In real work, the method for measuring optical centre deviation mainly contains two kinds: a kind of is static method, and another kind is rotary process.Static method is that to take the optical axis of some surveying instrument be benchmark, measures each centre of sphere autocollimation as the deviation of the deviation instrument optical axis, then calculates.And rotary process is to be measuring basis axle with a precision optical machinery axle, system under test (SUT) is fixed on turning axle, when axle when rotation system, all reflection autocollimatic pictures are all done and are drawn a circular motion, measure each centre of sphere autocollimatic picture and just obtain centre deviation with respect to the relative position at Hua Yuan center.

The Center Gap of measuring each element of optical system mainly contains two kinds of methods: a kind of is Mechanical Method, and another kind is interferometric method.Mechanical Method adopts the mode of contact to measure center thickness and the spacer ring thickness of optical element, by calculating the interval between optical element.Mechanical Method can only be measured in optical alignment, once dress gyp completes, just can not measure the center thickness of whole optical system and airspace, cannot judge the factor that affects image quality.Mechanical measurement adopts the airspace, center that indirectly measures optical system, and error is generally larger.Interferometric method is that the principle that adopts Michelson to interfere is measured, the method is with cordless, by interference of light, measure center thickness and the interval of optical element, its measuring accuracy can reach nanoscale, and interferometric method can be carried out the measurement at center thickness and interval after completing with dress school in the process of dress school.

At present, on market, there are a lot of commercial optical centre deviation measuring apparatus, are generally used for camera lens, the first-class compact optical element of camera lens.Optical centre deviation measuring apparatus for the high precision such as projection mask aligner's object lens, aerial survey camera lens, large-scale optical instrument, only have external fewer companies to manufacture, and price is very expensive.Although domestic have unit to develop optical centering instrument, do not form commercial product.The optical centering locating device that optical decentration difference measurements and optical center thickness and interval measurement are integrated in one, is not also having ripe product to occur in the market.Some unit is optical centering instrument and the optical orientator of purchasing respectively different company, by some devices, they is mechanically combined, the inevitable like this purchase cost that greatly improves.In addition, on market, commercial white light fibre optic interferometer is in measuring process, the power that can only detect reflected light beam signal by observation judges the alignment of two optical axises, cannot control survey beam optical axis and the alignment of tested system optical axis, cannot make its measuring beam optical axis and tested system optical axis accurately aim at, a little less than bringing measuring-signal, be difficult for surveying the problems such as operation inconvenience.

Due to the demand of working environment, some optical systems need to adopt the optical axis horizontal attitude work parallel with ground, or place with other complicated attitude, assemble the centre deviation that these optical systems must consider that optical element self gravitation brings.At present, the High Precision Central deviation measuring apparatus of selling on market generally adopts vertical rotating reflectometry, cannot effectively measure the centre deviation problem of these optical systems, as a large amount of horizontal work system all existing in the large-scale optical devices such as God Light device, space laser communication ground validation system, photo-etching machine illumination system.

Summary of the invention

The deficiency existing for above-mentioned prior art, the technical problem to be solved in the present invention is: a kind of optical system centering-setting device and using method thereof are provided, this device can be measured the centre deviation of optical element in optical alignment process simultaneously, center thickness and Center Gap, the device that optical system is felt relieved and located, this device is applicable to horizontal or has an assembling and setting of complex work attitude coaxial optical system such as turnover optical axis etc., also can promote the use of the centering orientation assemble of rotary reflection method optical system simultaneously, the measurement of the poor and center thickness of optical lens center deviation, the gummed of optical lens, the centering edging of optical lens, accurate measurement of angle, precision measurement etc.

Technical solution of the present invention is as follows:

A centering-setting device, feature is that its formation comprises internal focusing telescope, white light fibre optic interferometer, electronics part, computing machine, adjustment rack, guide rail and optical table, the position relationship of above-mentioned component is as follows:

Described white light fibre optic interferometer, electronics part, computing machine and guide rail are placed on described optical table, described internal focusing telescope is placed on described adjustment rack, described adjustment rack is a four-dimensional adjustment rack, for adjusting height, left and right displacement and pitching, the orientation of described internal focusing telescope, tilt, described adjustment rack is placed on described guide rail, described adjustment rack moves on described guide rail, for regulating moving axially of described internal focusing telescope;

Described internal focusing telescope is comprised of light source, condenser group, prism, field lens graticule, focusing lens group, fixed mirror group, spectroscope, relay lens and ccd detector, and described fixed mirror group, focusing lens group, field lens graticule, spectroscope, relay lens and ccd detector form the optical axis of internal focusing telescope;

The spectroscope of the fibre-coupled mirrors group of described white light fibre optic interferometer and described internal focusing telescope, field lens graticule common optical axis, this white light fibre optic interferometer has the function of the optical system autoscan of common optical axis being measured to center thickness and the Center Gap of each lens;

The light that described light source sends, convergence through condenser group, the reflection of prism, illumination field lens graticule, the picture of field lens graticule images in infinite point through focusing lens group and fixed mirror group, when the centre of sphere on the tested surface of optical system to be measured is just in time during the position of the picture in field lens graticule, the reflected light on this tested surface passes through again described fixed mirror group, focusing lens forms picture on the surface of field lens graticule, this picture is again through described spectroscope reflection, relay lens is assembled on the test surface that is imaged on described ccd detector, be called image, described field lens graticule itself is through described spectroscope reflection, relay lens is assembled and will be imaged on the center of the test surface of described ccd detector, be called field lens graticule picture,

Described electronics is partly for controlling the movement of internal focusing telescope focusing lens group and relay lens group, and record displacement information, described computing machine is connected with described ccd detector with described electronics part, the collaborative work of control device and data processing.

Described optical system to be measured or optical system to be installed are the coaxial optical system without central obscuration, and described optical system to be measured or optical system to be installed are placed on described optical table.

Utilize above-mentioned optical system centering-setting device to carry out the measuring method of optical system centre deviation and center thickness and Center Gap, its feature is that the method comprises the following steps:

1. on the optical table of described optical system centering-setting device, fix optical system to be measured, the optical axis that makes optical system to be measured is roughly basically identical with the optical axis of the internal focusing telescope of optical system centering-setting device, starts optical system centering-setting device;

2. pass through driven by servomotor, focusing lens group in mobile internal focusing telescope, make field lens graticule by focusing lens group and fixed mirror group, be imaged onto the centre of sphere of first surface of the first lens of optical system to be measured, the reflected light of first surface, is imaged on ccd detector and obtains the image b of first surface clearly through fixed mirror group, focusing lens group, field lens graticule, spectroscope, relay lens convergence successively; Meanwhile, field lens graticule is assembled and is imaged on ccd detector field of view center formation field lens graticule as a through spectroscope, relay lens group, regulates described adjustment rack that first surperficial image b is overlapped as a with described field lens graticule;

3. pass through driven by servomotor, focusing lens group in mobile internal focusing telescope, make field lens graticule be imaged onto second surperficial centre of sphere of tested optical system first lens, this second surperficial reflected light, assembles and is imaged on ccd detector acquisition second surperficial image b clearly through fixed mirror group, focusing lens group, field lens graticule, spectroscope, relay lens successively; Regulate adjustment rack that second surperficial image b of optical system to be measured overlapped with the picture a that is positioned at the field lens graticule of ccd detector field of view center;

4. repeating above-mentioned steps 3. 2. makes first surperficial image b of optical system to be measured and second surperficial image b all overlap as a with the field lens graticule of ccd detector field of view center with step; At this moment the optical axis of internal focusing telescope described in and the optical axis coincidence of the first lens of tested optical system, and claim that this optical axis is benchmark optical axis;

5. by driven by servomotor, mobile focusing lens group, makes field lens graticule be imaged onto the centre of sphere on the 3rd surface of optical system to be measured; By photoelectric encoder, measure the rotational angle θ of servomotor, the helical pitch P of known guide, calculates the fixedly distance between group and focusing group

by ccd detector, collect field lens graticule as the image of a and image b, adopt centroid method by image process obtain field lens graticule as a the centre coordinate (X on ccd detector ₀, Y ₀) and the centre coordinate (X of image b on ccd detector, Y), the pixel size PH of known ccd detector, utilize following formula calculate by the image b of the 3rd surface reflection of optical system to be measured and the field lens graticule of ccd detector field of view center as the distance C between a ':

$C^{\′}=\sqrt{{(X-X_0)}^2+{(Y-Y_0)}^2}\×\mathrm{PH};$

Wherein: the focal distance f of fixing group ₁', the focal distance f of focusing group ₂', fixing group is to the distance L of field lens graticule, the multiplying power β of relay lens _rfor known;

Utilize following formula to calculate the 3rd optical surface of optical system to be measured and the centre deviation of benchmark optical axis;

When the 3rd optical surface is sphere, its centre deviation be this optical surface centre of sphere to the distance of benchmark optical axis,

$C=\frac{C^{\&prime;}}{2\mathrm{\&beta;}}=\frac{C^{\&prime;}}{2{\mathrm{\&beta;}}_O\&CenterDot;{\mathrm{\&beta;}}_R}=\frac{1}{2{\mathrm{\&beta;}}_R}\&CenterDot;\frac{{{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_1}^{\&prime;}\&CenterDot;{{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;}}{{{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_1}^{\&prime;}\&CenterDot;({{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;}+e-L)-L\&CenterDot;({{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;}-e)-e^2}---\left(7\right)$

When the 3rd optical surface is plane, its centre deviation is the angle of this normal to a surface and benchmark optical axis,

$\mathrm{\&alpha;}=\frac{C^{\&prime;}\&CenterDot;{\mathrm{\&rho;}}^{\&prime;\&prime;}}{2{f_O}^{\&prime;}\&CenterDot;{\mathrm{\&beta;}}_R}=\frac{C^{\&prime;}\&CenterDot;{\mathrm{\&rho;}}^{\&prime;\&prime;}}{2{f^{\&prime;}}_Z}=\frac{C^{\&prime;}\&CenterDot;{\mathrm{\&rho;}}^{\&prime;\&prime;}}{2{\mathrm{\&beta;}}_R}\&CenterDot;\frac{{{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_1}^{\&prime;}+{{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;}-e_0}{{{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_1}^{\&prime;}\&CenterDot;{{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;}}---\left(8\right)$

6. 5., mobile focusing lens group, makes field lens graticule be imaged onto the 4th surface of optical system to be measured to repeating step, the 5th surface ..., the centre of sphere on last surface, meter is calculated the centre deviation of tested surface and benchmark optical axis respectively;

7. utilize the autoscan of white light fibre optic interferometer to measure center thickness and the Center Gap of each lens.

Utilize above-mentioned optical system centering-setting device optical system to be installed to be carried out the method for optical centering location when optical system is assembled, comprise the following steps:

1. on the optical table of described optical system centering-setting device, fix the first lens of optical system to be installed, the optical axis that makes optical system to be installed is roughly basically identical with the optical axis of the internal focusing telescope of optical system centering-setting device, starts optical system centering-setting device;

2. pass through driven by servomotor, focusing lens group in mobile internal focusing telescope, make field lens graticule by focusing lens group and fixed mirror group, be imaged onto the centre of sphere of the first surface of first lens, the reflected light of first surface, is imaged on ccd detector and obtains the image b of first surface clearly through fixed mirror group, focusing lens group, field lens graticule, spectroscope, relay lens convergence successively; Meanwhile, the field lens graticule that field lens graticule is imaged on ccd detector field of view center through spectroscope, relay lens group convergence, as a, regulates described adjustment rack that first surperficial image b is overlapped as a with described field lens graticule;

3. pass through driven by servomotor, mobile focusing lens group, make field lens graticule be imaged onto second surperficial centre of sphere of tested optical system first lens, this second surperficial reflected light, assembles and is imaged on ccd detector acquisition second surperficial image b clearly through fixed mirror group, focusing lens group, field lens graticule, spectroscope, relay lens successively; Regulate adjustment rack that second surperficial image b overlapped with the picture a that is positioned at the field lens graticule of ccd detector field of view center;

4. repeating above-mentioned steps 3. 2. makes first surperficial image b and second surperficial image b all overlap as a with the field lens graticule of ccd detector field of view center with step; At this moment the optical axis coincidence of the first lens of the optical axis of internal focusing telescope and tested optical system, and claim that this optical axis is benchmark optical axis;

5. according to the spacing of the design of second lens and first lens, second lens is installed;

6. repeat above-mentioned steps 2. with step 3., adjust second described lens, two surperficial image b of second lens are all overlapped as a with the field lens graticule that is positioned at ccd detector field of view center, complete the centering of second lens;

7. with white light fibre optic interferometer, measure the Center Gap of first lens and second lens, when the error of the Center Gap of measuring is within the scope of design tolerance, do not adjust, enter step 8., when the error of the Center Gap of measuring exceeds design tolerance scope, return to step 5.;

8. according to the spacing of the design of the 3rd lens and second lens, install and adjust the 3rd lens, repeat above-mentioned steps 6. with step 7.;

9. the like, the centering location that completes optical system.

The present invention compares and has following technique effect with technology formerly:

1, the present invention adopts the optical axis of horizontal internal focusing telescope as the optical axis of optical system centering location, has effectively solved the assembling and setting problem of optical system under horizontal optical system or other complex work attitudes.

2, the present invention has organically installed spectroscope, fibre-coupled mirrors group and the fiber bench with the light shaft coaxle of described internal focusing telescope on described internal focusing telescope, only the measuring optical fiber of described white light fibre optic interferometer need be inserted in described fiber bench, the optical axis of the light beam of the output of described white light fibre optic interferometer and input with organic coincidence of optical axis of described internal focusing telescope, while effectively having solved independent use white light interferometer measurement, a little less than reflected signal, be difficult for surveying the difficulties such as operation inconvenience.

3, of the present inventionly totally can carry out the measurement of centre deviation, Center Gap and center thickness to optical system simultaneously, realize optical instrument and debug centering and the location in process; The present invention in dress school process and dress school can carry out optical system after completing in the center thickness of optical element and the measurement at interval.

Accompanying drawing explanation

Fig. 1 is optical system centering orientator apparatus structure schematic diagram of the present invention

Fig. 2 is optical system centering orientator device optical schematic diagram of the present invention

Fig. 3 is internal focusing telescope object lens equivalent light path schematic diagram

Fig. 4 is the equivalent light path figures of internal focusing telescope object lens when outgoing directional light position

Fig. 5 is that field lens graticule picture and tested surface reflection are as schematic diagram

Fig. 6 is internal focusing telescope structural drawing

Fig. 7 is the composition structural drawing of electronics componental movement control system

Embodiment

Below in conjunction with embodiment and accompanying drawing, the present invention is further illustrated, but should not limit protection scope of the present invention with this.

First refer to Fig. 1, Fig. 1 is optical system centering orientator apparatus structure schematic diagram of the present invention, as seen from the figure, optical system centering-setting device of the present invention, adopt horizontal static reflex method measuring center deviation, adopt michelson interferometry to measure optical center thickness and Center Gap, its formation comprises internal focusing telescope 01, white light fibre optic interferometer 02, electronics part 03, computing machine 04, adjustment rack 05, guide rail 06, optical table 07 and tested optical system 08.

Internal focusing telescope 01 is imaged onto field lens graticule in the centre of sphere on tested surface by mobile focusing lens group, and its reflection image is received by ccd detector after interior focusing system, for measuring the centre deviation on tested surface;

White light fibre optic interferometer 02, by spectroscope, is coupled to its measuring beam in the light path of internal focusing telescope, and converges to tested surface, adopts michelson interferometry measuring principle to carry out the measurement of optical center thickness and Center Gap;

Electronics part 03 is for controlling the movement of internal focusing telescope 01 focusing lens group and relay lens group, and measures its displacement information, by calculating, can obtain the position of its utilizing emitted light beam convergence point and to reflecting the imaging multiplying power of graduation picture; Signal to ccd detector output carries out analyzing and processing, calculates the optical centre deviation on tested surface;

Computing machine 04 is for monitoring the various information of the process of debuging;

Adjustment rack 05 tilts for adjusting height, left and right displacement and pitching, the orientation of internal focusing telescope 01, is a four-dimensional adjustment rack;

Guide rail 06, for moving axially internal focusing telescope 01, provides suitable operating distance;

Optical table 07 provides a stabilised platform for optical centering locating device;

Tested optical system 08 is the coaxial optical system without central obscuration.

The optical principle of optical centering orientator as shown in Figure 2;

The light that light source 101 sends, through the convergence of condenser group 102, the reflection of prism 103, illumination field lens graticule 104, the picture of field lens graticule 104 images in infinite point through focusing lens group 105 and fixed mirror group 106.Change the position of focusing lens group 105, the picture of field lens graticule 104 can be from+be transferred to-∞ of ∞.When the centre of sphere on the tested surface of optical element 08 to be measured just in time overlaps with the picture of described field lens graticule 104 (plane can think that radius is infinitely-great sphere), light is by the tested surface reflection by described, this tested surface reflection is imaged on tested surface on the surface of field lens graticule 104 through fixed mirror group 106 and focusing lens group 105 again, the picture on this tested surface is again through spectroscope 107 reflections, and relay lens 108 is assembled and imaged on the test surface of ccd detector 109.

After the picture of field lens graticule 104 of internal focusing telescope and the centre of sphere on a certain tested surface of optical element to be measured 08 overlap substantially, the optical axis of the optical axis of internal focusing telescope and optical element to be measured 08 overlaps substantially.Now, also just basic coincidence of the measurement optical axis of white light fibre optic interferometer and the optical axis of optical element to be measured 08.

At this moment, short coherent source 201 sends reference beam and measuring beam, measuring beam is focused at field lens graticule 104 places by fibre-coupled mirrors group 203 and spectroscope 107, by 104 reflections of field lens graticule, through focusing lens group 105 and fixed mirror group 106, converge to the sphere center position on optical element to be measured 08 tested surface, light is by the tested surface reflection of optical element 08 to be measured, reflected light converges to white light fibre optic interferometer through interior focusing system again, this light beam and reference beam are through coupling mechanism 202 couplings, being detected device 205 receives, when mobile reference mirror 204 arrives a certain position, two-beam forms interferes, at this moment detector 205 obtains peak signal, by mobile reference mirror 204, can be formed and interfere on the different surface of element under test 08,204 displacements of precision measurement reference mirror, just can obtain Center Gap and center thickness between element under test 08 different surfaces,

Internal focusing telescope calculation of parameter is as follows:

When the centre of sphere of tested optical surface and the picture of field lens graticule 104 of optical element 08 to be measured has little deviation C, reflection image changes 2C, this amount is C ' after internal focusing telescope 2 amplifies, and the centre of sphere of optical element 8 tested optical surfaces to be measured and the deviation C of internal focusing telescope optical axis are:

$C=\frac{C^{\&prime;}}{2\mathrm{\&beta;}}---\left(1\right)$

Wherein: the enlargement ratio that β is internal focusing telescope, it equals interior focusing object lens multiplying power β _o(fixed mirror group 106 and focusing lens group 105 combination multiplying powers) and relay lens 108 multiplying power β _rproduct, i.e. β=β _o* β _r.

If tested surface is plane, the amount of deflection of plane is weighed with angle:

$\mathrm{\&alpha;}=\frac{C^{\&prime;}\&CenterDot;{\mathrm{\&rho;}}^{\&prime;\&prime;}}{2{f_O}^{\&prime;}\&CenterDot;{\mathrm{\&beta;}}_R}=\frac{C^{\&prime;}\&CenterDot;{\mathrm{\&rho;}}^{\&prime;\&prime;}}{2{f^{\&prime;}}_Z}---\left(2\right)$

Wherein: f _o' focal length value when interior focusing object lens (fixed mirror group 106 and focusing lens group 105) the outgoing directional light, " be constant, its value is 206265 to ρ, f ' _zthe combined focal length value of object lens and relay lens 108, i.e. f ' during for internal focusing telescope outgoing directional light _z=f _o' β _r

If the focal length of fixed mirror group is f ₁', the focal length of focusing lens group is f ₂', the distance between fixed mirror group and focusing lens group is e, as shown in Figure 3.When e value changes, field lens graticule picture is to distance S and the interior focusing object lens multiplying power β of fixed mirror group _oalso change, as shown in Figure 3.S, β _oand the relation between e is as follows:

$S=\frac{{{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_1}^{\&prime;}\&CenterDot;{{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;}\&CenterDot;(L-e)+{{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_1}^{\&prime;}\&CenterDot;e\&CenterDot;({{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;}-L+e)}{({{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_1}^{\&prime;}-e)\&CenterDot;({{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;}-L+e)-{{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;}\&CenterDot;(L-e)}---\left(3\right)$

${\mathrm{\&beta;}}_O=\frac{{{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_1}^{\&prime;}\&CenterDot;({{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;}+e-L)-L\&CenterDot;({{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;}-e)-e^2}{{{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_1}^{\&prime;}\&CenterDot;{{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;}}---\left(4\right)$

Wherein: L is the distance between field lens graticule and fixed mirror group.

As shown in Figure 4, when internal focusing telescope 2 outgoing directional light, the distance e between fixed mirror group and focusing lens group ₀for:

$e_0=\frac{(L+{{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_1}^{\&prime;})-\sqrt{{(L+{{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_1}^{\&prime;})}^2-4\&times;[L({{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_1}^{\&prime;}-{{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;})-{{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_1}^{\&prime;}{{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;}]}}{2}---\left(5\right)$

Interior focusing objective focal length f _o' be:

${f_O}^{\&prime;}=\frac{{{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_1}^{\&prime;}\&CenterDot;{{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;}}{{{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_1}^{\&prime;}+{{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;}-e_0}---\left(6\right)$

When the centre of sphere of tested optical surface and the picture of field lens graticule 104 have slight distance C, the tested surface reflection picture detecting on ccd detector and the distance between field lens graticule picture are C ', as shown in Figure 5.The deviation of the centre of sphere of tested optical surface and internal focusing telescope optical axis be can be calculated by formula (1) and (4):

$C=\frac{C^{\&prime;}}{2\mathrm{\&beta;}}=\frac{C^{\&prime;}}{2{\mathrm{\&beta;}}_O\&CenterDot;{\mathrm{\&beta;}}_R}=\frac{1}{2{\mathrm{\&beta;}}_R}\&CenterDot;\frac{{{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_1}^{\&prime;}\&CenterDot;{{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;}}{{{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_1}^{\&prime;}\&CenterDot;({{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;}+e-L)-L\&CenterDot;({{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;}-e)-e^2}---\left(7\right)$

When tested surface is plane, plane be can be calculated by formula (2) and (5) with respect to the amount of deflection of internal focusing telescope optical axis:

$\mathrm{\&alpha;}=\frac{C^{\&prime;}\&CenterDot;{\mathrm{\&rho;}}^{\&prime;\&prime;}}{2{f_O}^{\&prime;}\&CenterDot;{\mathrm{\&beta;}}_R}=\frac{C^{\&prime;}\&CenterDot;{\mathrm{\&rho;}}^{\&prime;\&prime;}}{2{f^{\&prime;}}_Z}=\frac{C^{\&prime;}\&CenterDot;{\mathrm{\&rho;}}^{\&prime;\&prime;}}{2{\mathrm{\&beta;}}_R}\&CenterDot;\frac{{{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_1}^{\&prime;}+{{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;}-e_0}{{{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_1}^{\&prime;}\&CenterDot;{{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;}}---\left(8\right)$

Like this, by measure the distance C between tested surface reflection picture and field lens graticule picture on ccd detector ', by calculating, can obtain the deviation of tested surface and internal focusing telescope optical axis; By obtaining the positional information of focusing lens group, can calculate field lens graticule picture to the distance of fixed mirror group.

Optical system centering-setting device, as shown in Figure 1, its formation comprises internal focusing telescope 01, white light fibre optic interferometer 02, electronics part 03, computing machine 04, adjustment rack 05, guide rail 06, optical table 07 and tested optical system 08.

Wherein, white light fibre optic interferometer 02 is commercial product, there is Optical fiber plug, can be connected to internal focusing telescope 01, the present embodiment adopts the LENSCAN-L1600 of Fogale company development, its measuring accuracy is ± 0.15 micron, and measurement range is 600 millimeters of optical lengths, operation wavelength 1310 nanometers.Computing machine 04, adjustment rack 05, guide rail 06 and optical table 07 are the universal product.

The NWJ-3 internal focusing telescope part light path that internal focusing telescope 01 adopts Shanghai ray machine to develop, with ccd detector as receiver, by the driven by motor focusing lens group with scrambler, move, by spectroscope, the measuring beam of white light interferometer is coupled into.As shown in Figure 6, its main composition comprises body 1 to the structure of specific embodiment, fixed mirror group 106, line slideway 2, screw mandrel 3, focusing lens group 105, field lens graticule 104, reflecting prism 103, condenser 102, light source 101, motor 4, photoelectric encoder 5, ccd detector 109, relay lens group 108, spectroscope 107, fibre-coupled mirrors group 203, fiber bench 6.Wherein, fixed mirror group 106 is fixed on body 1; Focusing lens group 105 is fixed on the slide block of line slideway 2, and the slide block of the slide block of line slideway 2 and screw mandrel 3 is fixed together by physical construction; Motor 4 with photoelectric encoder 5 passes through rotation, and the slide block that drives screw mandrel 3 to promote on line slideways 2 moves, thereby drives focusing lens group 105 along traveling priority; Field lens graticule 104 is glued on reflecting prism 103, by prism table, is fixed on body 1; Light source 101 is through the convergence of condenser 102, the indirect illumination field lens graticule 104 of reflecting prism 103; On spectroscope 107, plate wavelength 400nm～700nm reflection, the spectro-film of wavelength 1320nm transmission, this spectro-film is used for reflecting the picture of field lens graticule 104, and the measuring beam of white light fibre optic interferometer is transmitted in internal focusing telescope; Fibre-coupled mirrors group 203 is comprised of two lens; Fiber bench 6 is for the fixing Optical fiber plug of white light fibre optic interferometer of precision; Relay lens group 108 is comprised of a balsaming lens, by lens barrel, is fixed on body 1; Ccd detector 109 is fixed on the lens barrel of relay lens group 108.

The Main Function of electronics part 03:

1, control motor rotation, drive screw mandrel to rotate, drive focusing lens group along guide rail traveling priority; Photoelectric encoder and motor link together, and can measure the anglec of rotation of motor, can obtain the positional information of focusing lens group by measuring the anglec of rotation of motor; When field lens graticule is imaged onto the centre of sphere on tested surface, by photoelectric encoder, can measure the positional information of focusing lens group, according to formula (3), can calculate fixed mirror group to the distance of the tested surperficial centre of sphere; In addition, according to the design data of tested optical system, by calculating, focusing lens group directly can be moved to the centre of sphere on a certain tested surface, carry out the measurement of center deviation.

2, reading the field lens graticule that ccd detector collects is reflected by spectroscope, through relay lens group, the field lens graticule becoming is as a, and the field lens graticule reflection image b that becomes through focusing lens group, fixed mirror group, tested surface reflection of field lens graticule (as a and picture b as shown in Figure 5); By driving focusing lens group to move, when field lens graticule reflection image b is clear, illustrate that field lens graticule is imaged onto the centre of sphere on tested surface.

3, according to field lens graticule as a and field lens graticule reflection image b the position coordinates on ccd detector, can calculate distance C between b of picture a and picture '; According to the positional information of focusing lens group, can obtain focusing lens group to the position e of fixed mirror group, and according to the focal distance f of known fixed group ₁', the focal distance f of focusing group ₂', fixing group is to the distance L of field lens graticule, the multiplying power β of relay lens _r, according to formula (7) or (8), calculate the centre deviation of tested surface and benchmark optical axis.

In electronics part 03, the composition structural drawing of kinetic control system as shown in Figure 7.In the present embodiment, the Turbo PMAC2 type control card of motion control card 301Wei DELTATAU company, the Acc-8e of accessory card 302Wei DELTATAU company, the ACJ-55-18 of servo-driver 303Wei Copley company, the electrographite brush direct current generator 118730 that servomotor 4 is Maxon, the 512 line scramblers 201937 that scrambler 304 is Maxon.Wherein, motion control card 301 is inserted in the PCI slot in the cabinet of computing machine 04, and both carry out high-speed data communications by pci bus.The interface J9 (JMACH1) of motion control card 301 is connected with the JMACH1 interface of accessory card 302 through flat cable.Interface TB5, the J4 of accessory card 302 is connected with servo-driver 303, the order data that they send to servo-driver 303 for transmitting moving control card 301.Servo-driver 303 is intercepted order data, once obtain order data, it drives signal to direct current generator 4 output motor, thereby direct current generator 4 rotates and drive focusing lens group 105 to move along guide rail by screw mandrel 3.Meanwhile, the positional information of focusing lens group 5 finally feeds back to motion control card 301 by scrambler 304 by interface TB2, J1 on accessory card 302.Motion control card 301 is by positional information and the settings comparison of feedback, if focusing lens group 105 arrives desired location, to servo-driver 303, sends and ceases and desist order, otherwise continue monitoring.

In the present embodiment, it is 1/3 that ccd detector is selected optical dimensions ", pixel size is 4.65 μ m * 4.65 μ m, and resolution is 1024 * 768, and frame rate is 30fps, the industrial CCD detector that interface is USB2.0.Computing machine 04 is sent image acquisition order or reads the view data that ccd detector gathers to ccd detector by USB interface.

The measuring method of optical system centre deviation and center thickness and Center Gap, comprises the following steps:

1. on the optical table (07) of described optical system centering-setting device, fix optical axis that optical system to be installed (08) makes optical system to be installed (08) roughly basically identical with the optical axis of the internal focusing telescope of optical system centering-setting device, start optical system centering-setting device;

2. by driven by servomotor, move the focusing lens group (105) in internal focusing telescope, make field lens graticule (104) by focusing lens group (105) and fixed mirror group (106), be imaged onto the centre of sphere of the first surface of first lens, the reflected light of first surface, is imaged on ccd detector (109) and obtains the image b of first surface clearly through fixed mirror group (106), focusing lens group (105), field lens graticule (104), spectroscope (107), relay lens (108) convergence successively; Simultaneously, the field lens graticule that field lens graticule (104) is imaged on ccd detector (109) field of view center through spectroscope (107), relay lens group convergence, as a, regulates described adjustment rack (05) that first surperficial image b is overlapped as a with described field lens graticule;

3. by driven by servomotor, move the focusing lens group (105) in internal focusing telescope, make field lens graticule (104) be imaged onto second surperficial centre of sphere of tested optical system first lens, this second surperficial reflected light, assembles and is imaged on ccd detector (109) acquisition second surperficial image b clearly through fixed mirror group (106), focusing lens group (105), field lens graticule (104), spectroscope (107), relay lens (108) successively; Regulate adjustment rack (05) that second surperficial image b overlapped with the picture a that is positioned at the field lens graticule of ccd detector field of view center;

4. repeating above-mentioned steps 3. 2. makes first surface and second surperficial field lens graticule reflection image b all overlap as a with the field lens graticule of ccd detector field of view center with step; At this moment the optical axis coincidence of the first lens of the optical axis of internal focusing telescope and tested optical system, and claim that this optical axis is benchmark optical axis;

5. mobile focusing lens group, makes field lens graticule be imaged onto the centre of sphere on the 3rd surface of tested optical system; By photoelectric encoder, measure the rotational angle θ of servomotor, the helical pitch P of known guide, calculates the fixedly distance between group and focusing group

(as shown in Figure 3, Figure 4); By ccd detector, collect field lens graticule as the image of a and field lens graticule reflection image b, adopt centroid method by image process obtain field lens graticule as a the centre coordinate (X on ccd detector ₀, Y ₀) and the centre coordinate (X of field lens graticule reflection image b on ccd detector, Y), the pixel size PH of known ccd detector, utilize following formula calculate by the field lens graticule reflection image b of the 3rd surface reflection and at the field lens graticule of ccd detector field of view center as the distance C between a ':

$C^{\&prime;}=\sqrt{{(X-X_0)}^2+{(Y-Y_0)}^2}\&times;\mathrm{PH};$

The focal distance f of known fixed group ₁', the focal distance f of focusing group ₂', fixing group is to the distance L of field lens graticule, the multiplying power β of relay lens _r.

Utilize following formula to calculate the centre deviation of the 3rd optical surface and benchmark optical axis;

When the 3rd optical surface is sphere, its centre deviation be this optical surface centre of sphere to the distance of benchmark optical axis,

$C=\frac{C^{\&prime;}}{2\mathrm{\&beta;}}=\frac{C^{\&prime;}}{2{\mathrm{\&beta;}}_O\&CenterDot;{\mathrm{\&beta;}}_R}=\frac{1}{2{\mathrm{\&beta;}}_R}\&CenterDot;\frac{{{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_1}^{\&prime;}\&CenterDot;{{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;}}{{{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_1}^{\&prime;}\&CenterDot;({{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;}+e-L)-L\&CenterDot;({{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;}-e)-e^2}---\left(7\right)$

When the 3rd optical surface is plane, its centre deviation is the angle of this normal to a surface and benchmark optical axis,

$\mathrm{\&alpha;}=\frac{C^{\&prime;}\&CenterDot;{\mathrm{\&rho;}}^{\&prime;\&prime;}}{2{f_O}^{\&prime;}\&CenterDot;{\mathrm{\&beta;}}_R}=\frac{C^{\&prime;}\&CenterDot;{\mathrm{\&rho;}}^{\&prime;\&prime;}}{2{f^{\&prime;}}_Z}=\frac{C^{\&prime;}\&CenterDot;{\mathrm{\&rho;}}^{\&prime;\&prime;}}{2{\mathrm{\&beta;}}_R}\&CenterDot;\frac{{{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_1}^{\&prime;}+{{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;}-e_0}{{{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_1}^{\&prime;}\&CenterDot;{{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HDA0000126647860000031.png"\; state="\{\{state\}\}">f</figure-callout>}}_2}^{\&prime;}}---\left(8\right)$

6. mobile focusing lens group, makes field lens graticule be imaged onto the 4th surface, the 5th surface ..., the centre of sphere on last surface, meter is calculated the centre deviation of tested surface and benchmark optical axis respectively;

7. utilize the autoscan of white light fibre optic interferometer to can read center thickness and the Center Gap of each lens.

In optical system assembling, the method for optical centering location, comprises the following steps:

1. on the optical table (07) of described optical system centering-setting device, fix the first lens of optical system to be installed (08), the optical axis that makes optical system to be installed (08) is roughly basically identical with the optical axis of the internal focusing telescope of optical system centering-setting device, starts optical system centering-setting device;

2. by driven by servomotor, move the focusing lens group (105) in internal focusing telescope, make field lens graticule (104) by focusing lens group (105) and fixed mirror group (106), be imaged onto the centre of sphere of the first surface of first lens, the reflected light of first surface, is imaged on ccd detector (109) and obtains the image b of first surface clearly through fixed mirror group (106), focusing lens group (105), field lens graticule (104), spectroscope (107), relay lens (108) convergence successively; Simultaneously, the field lens graticule that field lens graticule (104) is imaged on ccd detector (109) field of view center through spectroscope (107), relay lens group convergence, as a, regulates described adjustment rack (05) that first surperficial image b is overlapped as a with described field lens graticule;

3. by driven by servomotor, move the focusing lens group (105) in internal focusing telescope, make field lens graticule (104) be imaged onto second surperficial centre of sphere of tested optical system first lens, this second surperficial reflected light, assembles and is imaged on ccd detector (109) acquisition second surperficial image b clearly through fixed mirror group (106), focusing lens group (105), field lens graticule (104), spectroscope (107), relay lens (108) successively; Regulate adjustment rack 05 that second surperficial image b overlapped with the picture a that is positioned at the field lens graticule of ccd detector field of view center;

4. repeating above-mentioned steps 3. 2. makes first surface and second surperficial field lens graticule reflection image b all overlap as a with the field lens graticule of ccd detector field of view center with step; At this moment the optical axis coincidence of the first lens of the optical axis of internal focusing telescope and tested optical system, and claim that this optical axis is benchmark optical axis;

5. according to the spacing of the design of second lens and first lens, second lens is installed;

6. repeat above-mentioned steps 2. with step 3., adjust second described lens, two surperficial image b of second lens are all overlapped as a with the field lens graticule that is positioned at ccd detector field of view center, complete the centering of second lens;

7. with white light fibre optic interferometer, measure the Center Gap of first lens and second lens, when the error of the Center Gap of measuring is within the scope of design tolerance, do not adjust, enter step 8., when the error of the Center Gap of measuring exceeds design tolerance scope, return to step 5.;

8. according to the spacing of the design of the 3rd lens and second lens, install and adjust the 3rd lens, repeat above-mentioned steps 6. with step 7.;

9. the like, the centering location that completes optical system.

Claims (3)

1. an optical system centering-setting device, be characterised in that its formation comprises internal focusing telescope (01), white light fibre optic interferometer (02), electronics part (03), computing machine (04), adjustment rack (05), guide rail (06) and optical table (07), the position relationship of above-mentioned component is as follows:

Described white light fibre optic interferometer (02), electronics part (03), computing machine (04) and guide rail (06) are placed on described optical table (07), described internal focusing telescope (01) is placed on described adjustment rack (05), described adjustment rack (05) is a four-dimensional adjustment rack, for adjusting the height of described internal focusing telescope (01), left and right displacement and pitching, orientation tilts, described adjustment rack (05) is placed on described guide rail (06), described adjustment rack (05) is in the movement of described guide rail (06), for regulating moving axially of described internal focusing telescope (01),

Described internal focusing telescope (01) is comprised of light source (101), condenser group (102), prism (103), field lens graticule (104), focusing lens group (105), fixed mirror group (106), spectroscope (107), relay lens (108) and ccd detector (109), and described fixed mirror group (106), focusing lens group (105), field lens graticule (104), spectroscope (107), relay lens (108) and ccd detector (109) form the optical axis of internal focusing telescope (01); Internal focusing telescope (01), moves by the driven by motor focusing lens group with scrambler as receiver with ccd detector (109), by spectroscope (107), the measuring beam of white light interferometer (02) is coupled into;

Spectroscope (107), field lens graticule (104) common optical axis of the fibre-coupled mirrors group (203) of described white light fibre optic interferometer (02) and described internal focusing telescope (01), this white light fibre optic interferometer (02) has the function of the optical system autoscan of common optical axis being measured to center thickness and the Center Gap of each lens;

The light that described light source (101) sends, convergence through condenser group (102), the reflection of prism (103), illumination field lens graticule (104), the picture of field lens graticule (104) images in infinite point through focusing lens group (105) and fixed mirror group (106), when the centre of sphere on the tested surface of optical system to be measured (08) is just in time during the position of the picture in field lens graticule (104), the reflected light on this tested surface passes through again described fixed mirror group (106), focusing lens group (105) is imaged on the surface of field lens graticule (104), this picture passes through described spectroscope (107) reflection again, relay lens (108) is assembled on the test surface that is imaged on described ccd detector (109), be called image, described field lens graticule (104) reflects through described spectroscope (107), relay lens (108) is assembled and will be imaged on the center of the test surface of described ccd detector (109), be called field lens graticule picture,

Described electronics part (03) is for controlling the movement of internal focusing telescope (01) focusing lens group and relay lens group, and record displacement information, described computing machine (04) is connected with described ccd detector (109) with described electronics part (03), the collaborative work of control device and data processing;

Tested optical system (08) is the coaxial optical system without central obscuration, and this tested optical system (08) is placed on described optical table (07).

2. utilize optical system centering-setting device described in claim 1 to carry out the measuring method of optical system centre deviation and center thickness and Center Gap, it is characterized in that the method comprises the following steps:

1. on the optical table (07) of described optical system centering-setting device, fix optical system to be measured (08), the optical axis that makes optical system to be measured (08) is roughly basically identical with the optical axis of the internal focusing telescope of optical system centering-setting device, starts optical system centering-setting device;

2. pass through driven by servomotor, focusing lens group (105) in mobile internal focusing telescope, make field lens graticule (104) by focusing lens group (105) and fixed mirror group (106), be imaged onto the centre of sphere of first surface of the first lens of optical system to be measured (08), the reflected light of first surface, is imaged on ccd detector (109) and obtains first surface image (b) clearly through fixed mirror group (106), focusing lens group (105), field lens graticule (104), spectroscope (107), relay lens (108) convergence successively; Simultaneously, field lens graticule (104) is assembled and is imaged on ccd detector (109) field of view center formation field lens graticule picture (a) through spectroscope (107), relay lens group, regulates described adjustment rack (05) that first surface image (b) is overlapped with described field lens graticule picture (a);

3. pass through driven by servomotor, focusing lens group (105) in mobile internal focusing telescope, make field lens graticule (104) be imaged onto the centre of sphere of the second surface of tested optical system first lens, the reflected light of this second surface, is imaged on ccd detector (109) and obtains second surface image (b) clearly through fixed mirror group (106), focusing lens group (105), field lens graticule (104), spectroscope (107), relay lens (108) convergence successively; Regulate adjustment rack (05) that the second surface image (b) of optical system to be measured (08) is overlapped with the field lens graticule picture (a) that is positioned at ccd detector field of view center;

4. repeating above-mentioned steps 3. 2. makes optical system to be measured (08) first surface image (b) and second surface image (b) all overlap with the field lens graticule picture (a) of ccd detector field of view center with step; At this moment the optical axis of internal focusing telescope described in and the optical axis coincidence of the first lens of tested optical system, and claim that this optical axis is benchmark optical axis;

5. by driven by servomotor, mobile focusing lens group, makes field lens graticule be imaged onto the centre of sphere on the 3rd surface of optical system to be measured (08); By photoelectric encoder, measure the rotational angle θ of servomotor, the helical pitch P of known guide, calculates the distance between fixed mirror group and focusing lens group

; By ccd detector, collect the image of field lens graticule picture (a) and the 3rd surperficial image (b), adopt centroid method to process and obtain the centre coordinate (X of field lens graticule picture (a) on ccd detector by image ₀, Y ₀) and the 3rd centre coordinate (X of surperficial image (b) on ccd detector, Y), the pixel size PH of known ccd detector, utilizes following formula calculate by the 3rd surperficial image (b) of optical system to be measured (08) and be positioned at the distance C ＇ between the field lens graticule picture (a) of ccd detector field of view center:

$C^{\&prime;}=\sqrt{{(X-X_0)}^2+{(Y-Y_0)}^2}\&times;\mathrm{PH};$

Wherein: the focal distance f of fixed mirror group ₁', the focal distance f of focusing lens group ₂', fixed mirror group is to the distance L of field lens graticule, the multiplying power β of relay lens _rfor known;

Utilize following formula to calculate the 3rd optical surface of optical system to be measured (08) and the centre deviation of benchmark optical axis:

When the 3rd optical surface is sphere, its centre deviation C is this optical surface centre of sphere to the distance of benchmark optical axis:

$C=\frac{C^{\&prime;}}{2\mathrm{\&beta;}}=\frac{C^{\&prime;}}{2{\mathrm{\&beta;}}_O\&CenterDot;{\mathrm{\&beta;}}_R}=\frac{1}{2{\mathrm{\&beta;}}_R}\&CenterDot;\frac{{f_1}^{\&prime;}\&CenterDot;{f_2}^{\&prime;}}{{f_1}^{\&prime;}\&CenterDot;({f_2}^{\&prime;}+e-L)-L\&CenterDot;({f_2}^{\&prime;}-e)-e^2}$

Wherein, the enlargement ratio that β is internal focusing telescope, it equals interior focusing object lens multiplying power β _owith relay lens multiplying power β _rproduct, i.e. β=β _o* β _r;

When the 3rd optical surface is plane, its centre deviation α is the angle of this normal to a surface and benchmark optical axis:

$\mathrm{\&alpha;}=\frac{C^{\&prime;}\&CenterDot;{\mathrm{\&rho;}}^{\&prime;\&prime;}}{{2f_O}^{\&prime;}\&CenterDot;{\mathrm{\&beta;}}_R}=\frac{C^{\&prime;}\&CenterDot;{\mathrm{\&rho;}}^{\&prime;\&prime;}}{2{f^{\&prime;}}_Z}=\frac{C^{\&prime;}\&CenterDot;{\mathrm{\&rho;}}^{\&prime;\&prime;}}{2{\mathrm{\&beta;}}_R}\&CenterDot;\frac{{f_1}^{\&prime;}+{f_2}^{\&prime;}-e_0}{{f_1}^{\&prime;}{\&CenterDot;f_2}^{\&prime;}}$

Wherein, f _o' focal length value when the interior focusing object lens outgoing directional light, ρ 〞 is constant, its value is 206265, f ' _zthe combined focal length value of object lens and relay lens, i.e. f ' during for internal focusing telescope outgoing directional light _z=f _o' β _r; When internal focusing telescope outgoing directional light, the distance between fixed mirror group and focusing lens group is e ₀;

6. 5., mobile focusing lens group, makes field lens graticule be imaged onto the 4th surface of optical system to be measured (08) to repeating step, the 5th surface ..., the centre of sphere on last surface, meter is calculated the centre deviation of tested surface and benchmark optical axis respectively;

7. utilize the autoscan of white light fibre optic interferometer to measure center thickness and the Center Gap of each lens.

3. utilize the optical system centering-setting device described in claim 1 optical system to be installed to be carried out the method for optical centering location when optical system is assembled, comprise the following steps:

1. on the optical table (07) of described optical system centering-setting device, fix the first lens of optical system to be installed (08), the optical axis that makes optical system to be installed (08) is roughly basically identical with the optical axis of the internal focusing telescope of optical system centering-setting device, starts optical system centering-setting device;

2. pass through driven by servomotor, focusing lens group (105) in mobile internal focusing telescope, make field lens graticule (104) by focusing lens group (105) and fixed mirror group (106), be imaged onto the centre of sphere of the first surface of first lens, the reflected light of first surface, is imaged on ccd detector (109) and obtains first surface image (b) clearly through fixed mirror group (106), focusing lens group (105), field lens graticule (104), spectroscope (107), relay lens (108) convergence successively; Simultaneously, field lens graticule (104) assembles through spectroscope (107), relay lens group the field lens graticule picture (a) that is imaged on ccd detector (109) field of view center, regulates described adjustment rack (05) that first surface image (b) is overlapped with described field lens graticule picture (a);

3. pass through driven by servomotor, mobile focusing lens group (105), make field lens graticule (104) be imaged onto the centre of sphere of the second surface of tested optical system first lens, the reflected light of this second surface, is imaged on ccd detector (109) and obtains second surface image (b) clearly through fixed mirror group (106), focusing lens group (105), field lens graticule (104), spectroscope (107), relay lens (108) convergence successively; Regulate adjustment rack (05) that second surface image (b) is overlapped with the field lens graticule picture (a) that is positioned at ccd detector field of view center;

4. repeating above-mentioned steps 3. 2. makes first surface image (b) and second surface image (b) all overlap with the field lens graticule picture (a) of ccd detector field of view center with step; At this moment the optical axis coincidence of the first lens of the optical axis of internal focusing telescope and tested optical system, and claim that this optical axis is benchmark optical axis;

5. according to the spacing of the design of second lens and first lens, second lens is installed;

6. repeat above-mentioned steps 2. with step 3., adjust second described lens, two surperficial images (b) of second lens are all overlapped with the field lens graticule picture (a) that is positioned at ccd detector field of view center, complete the centering of second lens;

7. with white light fibre optic interferometer, measure the Center Gap of first lens and second lens, when the error of the Center Gap of measuring is within the scope of design tolerance, do not adjust, enter step 8., when the error of the Center Gap of measuring exceeds design tolerance scope, return to step 5.;

8. according to the spacing of the design of the 3rd lens and second lens, install and adjust the 3rd lens, repeat above-mentioned steps 6. with step 7.;

9. the like, the centering location that completes optical system.

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