CN205580406U

CN205580406U - Autocollimator

Info

Publication number: CN205580406U
Application number: CN201620358714.4U
Authority: CN
Inventors: 叶海仙; 熊召; 陈海平; 独伟峰; 刘长春; 曹庭分; 易聪之; 袁晓东; 周海; 吴乾坤
Original assignee: Laser Fusion Research Center China Academy of Engineering Physics
Current assignee: Laser Fusion Research Center China Academy of Engineering Physics
Priority date: 2016-04-26
Filing date: 2016-04-26
Publication date: 2016-09-14
Anticipated expiration: 2026-04-26

Abstract

The utility model discloses an autocollimator, autocollimator includes light source, beam splitter, collimating lens, blazed grating and receiver, the laser of light source output passes through beam splitter, collimating lens and blazed grating in proper order, blazed grating places with the littrow angle in the light path, and n level diffraction light that blazed grating produced passes through collimating lens, beam splitter and receiver in proper order, and wherein n be non zero integer, and 0 grade of diffraction light of blazed grating production passes through blazed grating, collimating lens, beam splitter and receiver after being awaited measuring the surface reflection in proper order, the utility model discloses an autocollimator has the blazed grating that can produce real -time reference beam, can realize the automatic, real -time, accurate of indicating value drift and revise that greatly reduced high accuracy autocollimator is to the requirement of environment.

Description

A kind of autocollimator

Technical field

This utility model relates to small angle measurement instrument technical field, in particular to one certainly Collimator.

Background technology

Autocollimator is the common equipment of small angle measurement, and the flatness at angular surveying, flat board is surveyed Amount, the straight line degree measurement of guide rail, the angle of axle system are rocked the fields such as measurement and are widely used.High-precision Autocollimator is primarily limited to use environment, temperature in environment, air-flow, vibration etc. all can cause The drift of indicating value and beating.Even if environment is strictly controlled, indicating value drift also cannot be completely eliminated Move.Most common method is periodically autocollimator to be delivered to metrological service examine and determine at present, but Use environment to be typically difficult to as calibrating environment stable, use the indicating value drift that environmental change brings Remain uncontrollable.Thus cause the inaccurate of measurement result.

Utility model content

For above-mentioned problems of the prior art, this utility model provides a kind of autocollimator, Autocollimator of the present utility model with producing the balzed grating, of real-time reference light beam, Ke Yishi Existing indicating value drift automatic, real-time, accurately revise, be substantially reduced ultra-precise autocollimator to environment Requirement.

For achieving the above object, the following technical scheme of this utility model offer:

A kind of autocollimator, described autocollimator includes light source, beam splitter, collimating lens, glitters Grating and receptor, the laser of described light source output sequentially passes through beam splitter, collimating lens and glitters Grating, described balzed grating, is in the optical path with the placement of Littrow angle, the n level that balzed grating, produces Diffraction light sequentially passes through collimating lens, beam splitter and receptor, and wherein n is nonzero integer, glitters Grating produce 0 order diffraction light reflected by tested surface after, sequentially pass through balzed grating, collimating lens, Beam splitter and receptor.

Further, the one during described n order diffraction light is ± 1 grade and ± 2 order diffraction light.

Further, described balzed grating, surface is coated with aluminum film.

Further, described receptor is that charge coupled cell, four-quadrant photo detector or position are quick Sense detector.

The beneficial effects of the utility model: autocollimator of the present utility model is with producing in real time The balzed grating, of reference beam, the n order diffraction light work returned along original optical path that balzed grating, is produced For the reference beam of autocollimator, 0 order diffraction light of balzed grating, is incided as test beams Surface to be measured, owing to reference beam and test beams are produced by the same sheet gration within autocollimator Raw, the drift that environmental change causes is identical, by realizing indicating value after taking both difference The automatic correction of drift, it is thus achieved that real test result.

Accompanying drawing explanation

Fig. 1 is balzed grating, overall structure schematic diagram of the present utility model；

Fig. 2 is that tested surface heeling condition test beams transmits schematic diagram；

Fig. 3 is the reference beam drift schematic diagram that environment causes.

In figure: 1 light source, 2 beam splitters, 3 collimating lens, 4 balzed grating,s, 5 receive Device, 6 tested surfaces, 7 reference beams, 8 test beams.

Detailed description of the invention

In order to make those skilled in the art be more fully understood that the technical solution of the utility model, below in conjunction with Accompanying drawing of the present utility model, carries out clear, complete description to the technical solution of the utility model, Based on the embodiment in the application, those of ordinary skill in the art are not making creative work Other the similar embodiment obtained under premise, all should belong to the scope of the application protection.

Embodiment one:

As it is shown in figure 1, a kind of autocollimator, described autocollimator include light source 1, beam splitter 2, Collimating lens 3, balzed grating, 4 and receptor 5, the laser of described light source 1 output sequentially passes through Beam splitter 2, collimating lens 3 and balzed grating, 4, described balzed grating, 4 is in the optical path in order to spy Sieve angle is placed, and described balzed grating, 4 surface is coated with aluminum film, for reflective balzed grating, to appointing Meaning optical maser wavelength has high reflectance, and the n order diffraction light that balzed grating, 4 produces is as reference beam 7, reference beam 7 sequentially passes through collimating lens 3, beam splitter 2 and receptor 5, and wherein n is non- Zero integer, the one during preferred n order diffraction light is ± 1 grade and ± 2 order diffraction light in the present embodiment, The 0 order diffraction light that balzed grating, 4 produces is as test beams 8, and test beams 8 is by tested surface 6 After reflection, sequentially pass through balzed grating, 4, collimating lens 3, beam splitter 2 and receptor 5.Described Receptor 5 is charge coupled cell, four-quadrant photo detector or position sensitive detectors.Light source 1 is the LASER Light Source of any wavelength.Light source 1 is positioned at the focal position of collimating lens 3, benchmark Light beam 7 and test beams 8 all focus on after beam splitter 2 at receptor 5.

If as in figure 2 it is shown, tested surface 6 is relative to test beams 8 cant angle theta angle, through tested surface 6 After reflection, test beams 8 again passes by balzed grating, 4, collimating lens 3, beam splitter 2, finally Being received by receptor 5, the test beams 8 convergent point on receptor 5 is with meeting during vertical incidence Ideal distance between accumulation is d, according to autocollimating measurement principle, can calculate tested surface 6 Inclination angle:

D=2f θ

Wherein, f is the focal length of collimating lens.

As shown in Figure 3, it is assumed that the displacement that the angle drift that environment causes is corresponding on receptor 5 For Δ d, then the displacement of test beams 8 correspondence is that d '=(d+ Δ d), wherein d ' is receptor 5 displacements detecting test beams 8, d is that tested surface 6 tilts the actual displacement amount caused, And reference beam 7 displacement of correspondence on receptor 5 is Δ d ', due to reference beam 7 and survey Examination light beam 8 comes from the same a piece of balzed grating, 4 in autocollimator, therefore, Δ d '=Δ d, can To form difference structure, from the displacement of test beams 8, deduct the displacement of reference beam 7 i.e. Tested surface 6 can be obtained and tilt the actual displacement amount caused, it is achieved the real-time correction of indicating value drift.Pass through Regulation direction of displacement, makes d, d ', Δ d, Δ d ' on the occasion of or negative value, thus obtain tested surface The deflection angle of 6 and yawing moment.

It is exemplified below:

Balzed grating, 4 use 1 order diffraction light as reference beam 7, with incident beam overlaps；0 Order diffraction light is as test beams 8, with incident beam is vertical；Tested surface 6 inclination angle is θ, places Before autocollimator, test beams 8 reflects post deflection 2 θ through tested surface 6, again through glittering Grating 4, collimating lens 3, beam splitter 2, focus on receptor 5, according to the angle of collimating lens Degree-displacement relation, works as f=2m, and the inclination angle of tested surface 6 is 1 ', then tested surface tilts to cause Actual displacement amount be d=1mm, but the existence of the angle drift caused due to environment, test light The displacement restrainting 8 correspondences further comprises the displacement that environmental drift is corresponding, i.e. d '=d+ Δ d, d ' Directly recorded by receptor 5, in order to obtain real d value, it is necessary to record Δ d value, and reference light Restraint displacement Δ the d '=Δ d of 7 correspondences, be also directly to be recorded by receptor 5.The drift that environment causes The drift value of reference beam 7 correspondence within shifting amount is typically 5 " within, be calculated 5 " with Relation between the deviation angle of test beams 8 correspondence is as shown in the table:

Table 1

Environmental drift amount/"	1	2	3	4	5
						Displacement/μm that reference beam is corresponding	4.9	9.7	14.5	19.4	24.2
Displacement/μm that test beams is corresponding	1004.9	1009.7	1014.5	1019.4	1024.2
						Real d value/μm	1000	1000	1000	1000	1000
Real θ value/'	1	1	1	1	1

Moreover, it will be appreciated that although this specification is been described by according to embodiment, but the most every Individual embodiment only comprises an independent technical scheme, and this narrating mode of description is only For clarity sake, those skilled in the art should be using description as an entirety, in each embodiment Technical scheme can also form other that it will be appreciated by those skilled in the art that real through appropriately combined Execute mode.

Claims

1. an autocollimator, it is characterised in that described autocollimator include light source, beam splitter, Collimating lens, balzed grating, and receptor, described light source output laser sequentially pass through beam splitter, Collimating lens and balzed grating, described balzed grating, is placed with Littrow angle in the optical path, is glittered The n order diffraction light that grating produces sequentially passes through collimating lens, beam splitter and receptor, and wherein n is Nonzero integer, after the 0 order diffraction light that balzed grating, produces is reflected by tested surface, sequentially passes through and glitters Grating, collimating lens, beam splitter and receptor.

Autocollimator the most according to claim 1, it is characterised in that described n order diffraction light For the one in ± 1 grade and ± 2 order diffraction light.

Autocollimator the most according to claim 1, it is characterised in that described balzed grating, table Face is coated with aluminum film.

Autocollimator the most according to claim 1, it is characterised in that described receptor is electricity Lotus coupling element, four-quadrant photo detector or position sensitive detectors.