CN205192728U - Star sensor optical system multiplying power colour difference test equipment - Google Patents

Abstract

A magnification chromatic aberration test device for a star sensor optical system, the test device includes a target simulation part, a measured optical system installation part, a microscopic acquisition part and a control and data processing computer; a target simulation part, a test optical system installation part and a display The micro-acquisition components are sequentially arranged on the same optical path; the target simulation components include a monochromator, a collimator, a filter target wheel, and a target target wheel; the filter target wheel and the target target wheel are sequentially set on the exit light on the road; the target surface of the target target wheel coincides with the focal plane of the collimator; the optical system to be tested is set on the installation part of the optical system to be tested; the control and data processing computers are respectively connected to the monochromator, with various spectral The filter target wheel of the segment range filter, the target target wheel with multiple groups of target plates are connected with the installation parts of the optical system under test. The utility model has the advantages of high testing efficiency, fewer testing personnel and expanded testing range.

Description

Star sensor optical system magnification chromatic aberration test equipment

technical field

The utility model belongs to the field of optical detection, and relates to an automatic test device for key parameters of an optical system of a star sensor, in particular to a test device for automatically measuring the magnification chromatic aberration of the optical system of a star sensor.

Background technique

The star sensor is a high-precision space attitude measurement device with the star as the reference system, the starry sky as the working object, and the satellite, spacecraft, aircraft, ship and missile as the carrier. When working, it detects the positions of different stars on the celestial sphere, Compare it with known star maps to provide accurate spatial orientation and benchmarks for the carrier.

The star sensor optical system is an important part of the star sensor, and its parameters (such as spectral energy concentration and chromatic aberration of magnification, etc.) directly affect the performance index of the star sensor system. Among them, the spectral energy concentration is to investigate whether the diameters of the point diffusion circles distributed on the image surface in different spectral bands are within a specific range. Most of the energy is concentrated between 1×1 and 3×3 pixels. In addition, the chromatic aberration of magnification is to investigate whether the centroid position of the point diffusion circle of different spectral bands in the same field of view is within a certain range. In order to make the error not affect the attitude measurement of the whole machine, it is generally necessary to make it not greater than 0.3 pixel size . The above two indicators are reflected in the whole system, which can ensure that the star sensor can accurately determine the position of stars in different spectral bands, and will not cause differences in the accuracy of the center of mass position due to different spectral bands, thereby ensuring that the star sensor is its carrier Provides accurate attitude measurement data. It can be seen that the accurate measurement of spectral energy concentration and chromatic aberration of magnification is very important for the star sensor system.

At present, spectral energy concentration and chromatic aberration of magnification are the most labor-intensive and time-consuming items in the star sensor optical system test indicators. Due to the influence of the field of view and spectrum of the test, there are many test points for the above two indicators. It is not only time-consuming and labor-intensive to manually change the position of the test points and the spectrum of the light source, but it is also inevitable that various human-made test errors will appear.

In addition, due to the different application ranges of star sensors, the requirements for light sources are also different. When testing the above two indicators, some models need to give test data under monochromatic light at different spectral positions, and some models need to give test data within a certain spectral range. At present, in order to meet the test technical indicators, often Change the light source to suit different needs.

The existence of these limitations makes the star sensor optical system test process a bottleneck in the entire development process, hindering the process of star sensor productization, and is the basis for the star sensor on satellites, spacecraft, aircraft, ships and missiles. A major obstacle to widespread use.

Therefore, it is very necessary to develop an automatic magnification chromatic aberration testing equipment for optical systems.

Utility model content

In order to solve the above-mentioned technical problems in the background technology, the utility model provides a magnification chromatic aberration testing device for a star sensor optical system with high testing efficiency, fewer testing personnel and expanded testing range.

The technical solution of the utility model is: the utility model provides a chromatic aberration of magnification test equipment for the optical system of the star sensor, which is characterized in that: the chromatic aberration of magnification test equipment for the optical system of the star sensor includes a target simulation component, a measured optical system Mounting components, microscopic collection components, and control and data processing computers; the target simulation components, the measured optical system installation components, and the microscopic collection components are sequentially arranged on the same optical path; the target simulation components include a monochromator, a parallel light Tubes, filter target wheels with various spectral range filters required for testing, and target target wheels with sets of target plates; said with various spectral range filters required for testing The filter target wheel and the target target wheel with multiple groups of target plates are sequentially arranged on the exit light path of the monochromator; the target surface of the target target wheel with multiple groups of target plates coincides with the focal plane of the collimator The optical system to be tested is arranged on the installed part of the optical system to be tested; the control and data processing computer are respectively connected with the monochromator, the filter target wheel with various spectral range filters required for the test, and the There are multiple sets of target wheels of the target board and the installation parts of the optical system to be tested are connected.

A set of discrimination rate boards, a set of Polo boards and multiple sets of star point boards are installed on the target target wheel with multiple sets of target boards.

The determination mode of the diameter of the star point on the above-mentioned multiple groups of star point boards is:

$\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; ></span>\frac{\mathrm{<span\; class="notranslate">\; 0.61</span>}\mathrm{<span\; class="notranslate">\; \&lambda;</span>}\mathrm{<span\; class="notranslate">\; f</span>}}{\mathrm{<span\; class="notranslate">\; D.</span>}}$

In the formula:

d is the diameter of the star point on the star point plate, in micrometers (μm);

λ is the central wavelength of the optical system under test, in microns (μm);

F is the focal length of the collimator, in millimeters (mm);

D is the entrance pupil diameter of the optical system under test, in millimeters (mm).

The installation part of the above-mentioned optical system under test includes a pitch and level adjustment device and a mounting flange; the installation flange is arranged on the pitch and level adjustment device; the measured optical system is arranged on the installation flange; the control and data processing computer Connected to the pitch and level adjustment device.

The above-mentioned microscopic acquisition components include an electric control turntable and a three-dimensional CCD microscopic acquisition system arranged on the electric control turntable; the three-dimensional CCD microscopic acquisition system includes a three-dimensional translation platform and a CCD microscopic system arranged on the three-dimensional translation platform; The control and data processing computers are respectively connected with the electric control turntable and the three-dimensional CCD microscopic acquisition system.

The above-mentioned three-dimensional translation stage includes an X-direction electric translation stage perpendicular to the optical axis direction and parallel to the table surface of the electric control turntable, a Y-direction electric translation stage perpendicular to the optical axis direction and perpendicular to the table surface of the electric control turntable, and an electric control translation stage along the Z direction electronically controlled translation stage in the optical axis direction.

The above-mentioned monochromator includes a spectrometer, and the spectrometer emits zero-order light or emits monochromatic light of 300nm-1200nm.

The utility model has the advantages of:

The automatic test equipment for the key parameters of the star sensor optical system provided by the utility model can automatically test the chromatic aberration of magnification, and can simultaneously measure the focal length, entrance pupil diameter, field of view, back working distance, back intercept, axial chromatic aberration and other indicators The test can cover 80% of the conventional test indicators of the star sensor optical system. The automatic testing equipment for the key parameters of the star sensor optical system provided by the utility model can also test the relevant indicators of the optical system for other purposes, and has a wide range of applications; it can meet the test requirements of white light, monochromatic light or a certain spectrum of chromatic light. The automatic test of chromatic aberration of magnification does not need to frequently replace the light source or the test equipment; the automatic test processing system has high stability, and the test speed is 2 times higher than that of the complete manual test, saving manpower and material resources, and it is the original small optical system for the star sensor. Mass production to the present product production has played a great role.

Description of drawings

Fig. 1 is the structural representation of the test equipment provided by the utility model;

in:

1-collimator; 2-target target wheel; 3-filter target wheel; 4-monochromator; 5-pitch and level adjustment device; 6-installation flange; 7-electric control turntable; 8-Y direction 9-Z direction electric control translation stage; 10-X direction electric control translation stage; 11-CCD microscope system; 12-control and data processing computer.

detailed description

Referring to Fig. 1, the star sensor optical system chromatic aberration of magnification testing equipment provided by the utility model comprises: target simulation part, measured optical system mounting part, microscopic acquisition part, control and data processing computer 12; target simulation part, The installation part of the optical system under test and the microscopic collection part are sequentially arranged on the test optical axis; the control and data processing computers are respectively connected with the target simulation part, the installation part of the optical system under test and the microscopic collection part.

The target simulation components include a monochromator 4, a filter target wheel 3, a target target wheel 2 and a collimator 1; the light outlet of the monochromator 4 faces the focal plane of the collimator 1; the filter target wheel 3 is located in the monochromator Between 4 and the target target wheel 2; the target surface of the target target wheel 2 coincides with the focal plane of the collimator 1, as follows:

1) The monochromator 4 includes two parts: a xenon lamp and a spectrometer; the spectrometer can meet the requirements of emitting zero-order light (that is, the original light of the xenon lamp that has not passed through the grating in the spectrometer) and emitting 300nm-1200nm monochromatic light (resolution 0.1nm);

2) The filter target wheel 3 includes multiple sets of filter installation positions, which can be installed with filters of various spectral ranges required for testing;

3) The target target wheel 2 includes multiple sets of target board installation positions, and can install discrimination rate boards, Perot boards and star point boards, wherein the discrimination rate boards are one group, the Perot boards are one group, and the star point boards are multiple groups;

The installation part of the optical system under test includes a mounting flange 6, a pitch and level adjustment device 5, and the mounting flange 6 is located above the pitch and level adjustment device 5;

Microscopic acquisition components include a three-dimensional CCD microscopic acquisition system and an electronically controlled turntable 7; the three-dimensional CCD microscopic acquisition system is located on the electronically controlled turntable 7; the three-dimensional CCD microscopic acquisition system includes a CCD microscopic system 11 and three translation stages: It is an X-direction electric control translation stage 10 perpendicular to the optical axis direction and parallel to the turntable table surface, a Y-direction electric control translation stage 8 perpendicular to the optical axis direction and perpendicular to the turntable table surface, and a Z-direction electric control translation stage along the optical axis direction station 9;

The control and data processing computer 12 can control all the electronic control devices mentioned above, including the monochromator 4, the filter target wheel 3, the target target wheel 2, the pitch and level adjustment device 5, the CCD microscopic system 11, and the X-direction electric control translation Table 10, Y-direction electric control translation table, Z-direction electric control translation table 9 and electric control turntable 7;

The test method of the star sensor optical system magnification chromatic aberration test equipment provided by the utility model is:

1) Configure suitable target simulation components and suitable microscope objectives;

2) Install the optical system under test;

3) The microscopic acquisition part collects and enlarges the image formed by the image plane of the optical system under test, and transfers it to the two edges, and fine-tunes the optical system installation unit according to the size and shape of the formed image, so that its optical axis is parallel to the optical axis of the target analog component ;

4) Parameter setting: including the parameter setting of the optical system under test and the parameter setting of the test method;

5) System automatic test: including the electric control turntable and the X-direction electric control translation table to automatically move to the position of the collection point, the target simulation part automatically replaces white light, monochromatic light or a certain spectrum of color light according to the parameter settings, and automatically collects the required data. The software The background automatically calculates the final data;

6) Output the test report.

The specific implementation of the above method is as follows:

1) Select a suitable microscopic objective lens according to the relative aperture of the optical system under test, that is, the numerical aperture of the microscopic objective lens should be greater than 1/2 of the relative aperture of the optical system under test;

2) According to the diameter of the entrance pupil of the optical system under test, the focal length of the collimator 1 and the technical indicators to be tested, configure suitable target simulation components:

a) Configure target target wheel 2:

If the chromatic aberration of magnification of the optical system is tested, the diameter d of the star point is selected according to the formula (1),

$d>\frac{0.61\mathrm{\&lambda;}f}{\mathrm{D.}}$ Formula 1)

In the formula:

λ is the central wavelength of the optical system under test, in microns (μm);

F is the focal length of collimator 1, and the unit is millimeter (mm);

D is the entrance pupil diameter of the optical system under test, in millimeters (mm).

Input the selected star point diameter and its number on the target target wheel 2 into the software for configuration, as shown in Table 1:

Table 1 Target wheel 2 number and target plate example

target location target board 1# Discrimination board

2# 0.1mm star point 3# 0.2mm star point 4# 0.005mm star point

b) Configure filter target wheel 3:

If it is necessary to test the indicators under monochromatic light or white light, select the through hole of the filter target wheel, that is, do not pass any filter for testing;

If it is necessary to test the indicators under the color light of a certain spectrum, the filters of each spectrum to be tested are installed on the filter target wheel 3;

Input the number of the through hole and each spectral band filter on the filter target wheel 3 into the software for configuration, as shown in Table 2:

Table 2 No. of filter target wheel 3 and examples of filters

Filter position center wavelength bandwidth 1# through hole / 2# 400nm ±100nm 3# 500nm ±100nm 4# 600nm ±100nm 5# 700nm ±100nm 6# 400nm ±50nm 7# 450nm ±50nm 8# 500nm ±50nm 9# 550nm ±50nm 10# 600nm ±50nm

3) Install the optical system under test on the mounting flange 6, and adjust the pitch and level adjustment device 5 by observing the line between the reflective points of the lenses of the optical system under test until all the reflective points are on the same straight line;

4) By adjusting the position of the CCD microscope system 11 on the Y-direction electronically controlled translation stage 8, the Z-direction electronically controlled translation stage 9, and the X-direction electronically controlled translation stage 10, it can collect the image at the image plane of the optical system under test , cooperate with the electric control turntable 7 and the X-direction electric control translation stage 10 to move to the two edges of the optical system, fine-tune the optical system installation unit according to the size and shape of the formed image, until the size and shape of the image formed on both sides are close, that is, the measured The optical axis of the optical system is parallel to the optical axis of the target simulation component;

5) Parameter setting:

a) Parameter setting of the optical system under test: including the focal length f and the half field angle ω of the optical system under test;

b) Test method parameter setting: (set method parameters according to test indicators)

If the test index is the chromatic aberration of magnification, you need to input the magnification N of the microscope objective lens used, the test spectrum (if it is monochromatic light, then input the position number of the through hole of the filter target wheel 3, and input the sequence required by the monochromator 4 at the same time. The converted monochromatic light wavelength; if it is a certain spectral segment chromatic light, then input the desired spectral segment chromatic light position numbers configured on the filter target wheel 3 in sequence, and simultaneously input the monochromator 4 to output the zero-order light), the selected star The position number of the point on the target target wheel 2, the test normalized field of view (such as 0.3 field of view, 0.5 field of view, etc.), the criterion (that is, the qualified range of the magnification color difference test result), etc.;

c) Other settings: collect data storage path, input test personnel, test temperature and humidity and other information.

6) Automatically test the chromatic aberration of magnification, the specific test method is:

a) The electronically controlled turntable 7 rotates counterclockwise to the maximum field of view to be tested, that is, -|θ _max |, and the X-direction electronically controlled translation platform 10 moves to the left to the edge correspondingly, and the amount of movement is:

a=f×tan(|θ _max |) formula (2)

In the formula:

a is the movement amount of the electronically controlled translation platform in the X direction, in millimeters (mm);

f is the focal length of the optical system under test, in millimeters (mm);

θ _max is the maximum field of view to be tested, calculated by the software based on the set maximum normalized field of view and half field of view ω, if the maximum normalized field of view is 0.8 field of view, then θ _max = 0.8× ω, in degrees (°).

b) At the field of view, change the test wavelength in turn, and calculate the row coordinates x _λi and column coordinates y _λi of the centroid respectively according to the following formula, and calculate the chromatic aberration of magnification between the centroid coordinates of each wavelength and the centroid coordinates of the center wavelength, And save the row coordinates x _λi , column coordinates y _λi and chromatic aberration of magnification of each wavelength in the saving path set in step 5) in order;

the row coordinates of the centroid

the column coordinates of the centroid

Note 1: The test wavelength replacement method is as follows:

If it is white light/monochromatic light, the filter target wheel 3 is turned to the through hole, and the white light or the set monochromatic light is replaced sequentially through the monochromator; if it is a certain spectrum of color light, the monochromator 4 outputs zero The secondary light passes through the filter target wheel 3 and rotates sequentially according to the configured number of color light positions in the desired spectrum.

It is consistent with the automatic test procedure of energy concentration.

Note 2: The calculation method of chromatic aberration of magnification is as follows:

i) Identify the effective target area and remove the background from the effective target area;

ii) Calculate the row coordinates x _λ and column coordinates y _λ of the centroid of the star point image at the same field of view and at different wavelengths according to formula (4-1) and formula (4-2);

iii) Calculate the chromatic aberration of magnification according to the following formula:

${\mathrm{<span\; class="notranslate">\; \&Delta;</span>}}_{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; d</span>}}{\mathrm{<span\; class="notranslate">\; N</span>}}<span\; class="notranslate">\; \&times;</span>\sqrt{{<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; +</span>{<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}}{<span\; class="notranslate">\; -</span>}_{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}$

In the formula:

_Δλ is the chromatic aberration of magnification at wavelength λ;

d is the CCD pixel size, the unit is micron (μm);

N is the magnification of the objective lens;

x _λ is the row coordinate of the centroid of the star image at the wavelength λ;

y _λ is the column coordinate of the center of mass of the star image at the wavelength λ;

x _λ0 is the row coordinate of the center of mass of the star image at the center wavelength of the optical system;

y _λ0 is the column coordinate of the center of mass of the star image at the center wavelength of the optical system;

c) After the chromatic aberration of magnification at all wavelengths at the field of view is collected, transfer to the next field of view for testing;

d) After the chromatic aberration of magnification at all preset fields of view is tested, it will prompt that the test is completed and display the test data;

e) The test results can be shown in Table 3:

Table 3 magnification color difference test result table

7) Output the test report, which includes: test indicators, test time, test equipment (indicating the multiple of the test objective lens and the size of the star point), test personnel, test temperature and humidity, and test data.

Claims (5)

1. an optical system of star sensor ratio chromatism, testing apparatus, is characterized in that: described optical system of star sensor ratio chromatism, testing apparatus comprises target simulation parts, tested optical system installing component, micro-acquisition component and control and data handling machine; Described target simulation parts, tested optical system installing component and micro-acquisition component are set in turn in same light path; Described target simulation parts comprise monochromator, parallel light tube, take turns and take turns with the target organizing Target Board more with the optical filter target of the various spectral coverage scope optical filters needed for test; The described optical filter target with the various spectral coverage scope optical filters needed for test is taken turns and is successively set on the emitting light path of monochromator on the target wheel organizing Target Board more; The target surface of the described target wheel with many group Target Boards overlaps with parallel light tube focal plane; Optical system to be measured is arranged on tested optical system installing component; Described control and data handling machine respectively with monochromator, take turns with the optical filter target of the various spectral coverage scope optical filters needed for testing, to take turns with the target organizing Target Board and tested optical system installing component is connected more;

The described target wheel with many group Target Boards is fitted with one group of resolution chart, one group of Porro tester and organizes star tester more;

The determination mode of the diameter of the asterism on described many group star testers is:

In formula:

D is the diameter of the asterism on star tester, and unit is micron;

λ is the centre wavelength of tested optical system, and unit is micron;

F is the focal length of parallel light tube, and unit is millimeter;

D is the Entry pupil diameters of tested optical system, and unit is millimeter.

2. optical system of star sensor ratio chromatism, testing apparatus according to claim 1, is characterized in that: described tested optical system installing component comprises pitching and level(l)ing device and mounting flange; Described mounting flange is arranged on pitching and level(l)ing device; Tested optical system is arranged on mounting flange; Described control and data handling machine are connected with pitching and level(l)ing device.

3. optical system of star sensor ratio chromatism, testing apparatus according to claim 2, is characterized in that: described micro-acquisition component comprises automatically controlled turntable and is arranged on the micro-acquisition system of three-dimensional CCD on automatically controlled turntable; The micro-acquisition system of described three-dimensional CCD comprises D translation platform and is arranged on the CCD microscopic system on D translation platform; Described control and data handling machine are connected with automatically controlled turntable and the micro-acquisition system of three-dimensional CCD respectively.

4. optical system of star sensor ratio chromatism, testing apparatus according to claim 3, is characterized in that: described D translation platform comprise perpendicular to optical axis direction and the X paralleled with the table top of automatically controlled turntable to electronic control translation stage, perpendicular to optical axis direction and the Y-direction electronic control translation stage perpendicular with the table top of automatically controlled turntable and the Z-direction electronic control translation stage along optical axis direction.

5. optical system of star sensor ratio chromatism, testing apparatus according to claim 4, is characterized in that: described monochromator comprises spectrometer, described spectrometer outgoing zero degree light or outgoing 300nm ~ 1200nm monochromatic light.