CN206057620U - A kind of producing device of holographic grating array - Google Patents
A kind of producing device of holographic grating array Download PDFInfo
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- CN206057620U CN206057620U CN201621069926.7U CN201621069926U CN206057620U CN 206057620 U CN206057620 U CN 206057620U CN 201621069926 U CN201621069926 U CN 201621069926U CN 206057620 U CN206057620 U CN 206057620U
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- light
- producing device
- beam splitter
- light source
- holographic grating
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Abstract
The utility model discloses a kind of producing device of holographic grating array, including light source, collimating mirror, diaphragm, shutter, beam splitter, two-face mirror, light gate substrate and mobile platform, wherein light source adopts laser diode, the direction that light source, collimating mirror and diaphragm advance along light beam co-axial alignment successively, beam splitter is arranged in light path of the light beam after diaphragm, for light beam is reflected into two light beams, shutter is arranged between light source and beam splitter and coaxial with light beam beam splitter；Two-face mirror is separately positioned in the light path of two light beams Jing after beam splitter reflection, and two-face mirror is arranged by axle axial symmetry of beam splitter, and light gate substrate is arranged on mobile platform, and light gate substrate is located at interference field.The utility model proposes holographic grating array producing device, the holographic grating array of making can apply to one-dimensional grating chi, and greatly reduce the cost of light source, simplifies structure, volume and also greatly reduces.
Description
Technical field
This utility model is related to holographic grating making field, more particularly to a kind of producing device of holographic grating array.
Background technology
Grating scale is accurate measurement, the important survey tool in Precision Machining, and grating as the critical component of grating scale is
The physics scale of grating measuring, its length and cycle directly determine measurement range and resolution.The laser interference commonly used at present
Lithography process method simple system, period modulation are convenient, and single can process 100mm length, the grating in submicron cycle.
But, in laser interference photolithography technology, grating length is directly decided by the coherence length of laser and universal optical device
The size of part, the grating for processing 100mm magnitudes must adopt coherence length in the gas or solid large-scale laser of 1000mm levels
With large-sized customization optics and huge beam-expanding system.Such system of processing is involved great expense, takes up an area space greatly, and one
As research unit be difficult to undertake, be unfavorable for popularizing for the technology.
The disclosure of background above technology contents is only used for auxiliary and understands design of the present utility model and technical scheme, and which is not
The prior art of present patent application is necessarily belonged to, shows the applying date of the above in present patent application there is no tangible proof
In the case of disclosed, above-mentioned background technology should not be taken to the novelty and creativeness for evaluating the application.
Utility model content
To solve above-mentioned technical problem, the utility model proposes a kind of producing device of holographic grating array, making it is complete
Breath grating array can apply to one-dimensional grating chi, and greatly reduce the cost of light source, simplifies structure, volume and also subtracts significantly
It is little.
To reach above-mentioned purpose, this utility model is employed the following technical solutions：
The utility model discloses a kind of producing device of holographic grating array, including light source, collimating mirror, diaphragm, shutter,
Beam splitter, two-face mirror, light gate substrate and mobile platform, it is wherein the light source adopts laser diode, the light source, described
The direction that collimating mirror and the diaphragm advance along light beam co-axial alignment successively, the beam splitter are arranged on the light beam through described
In light path after diaphragm, the beam splitter for the light beam is reflected into two light beams, the shutter be arranged on the light source with
It is between the beam splitter and coaxial with the light beam；Reflecting mirror described in two sides be separately positioned on the reflection of described in beam splitter after two
In the light path of light beam, reflecting mirror described in two sides is arranged by axle axial symmetry of the beam splitter, and the smooth gate substrate is arranged on described
On mobile platform, and the smooth gate substrate is located at interference field.
Preferably, the shutter adopts electronic shutter, the opening time of the electronic shutter to be equal to and form holographic grating
Single exposure time, the shut-in time of the electronic shutter are equal to the time needed for mobile platform single movement.
Preferably, the producing device also includes light barrier, and the light barrier is provided with rectangular slot, and the light barrier is solid
Surely the grating surface is arranged on, the rectangular slot is correspondingly arranged to be formed at the position of holographic grating.
Preferably, the light barrier is using the thin plate for being close to the smooth gate substrate, the width of the rectangular slot be less than or
The width of the holographic grating formed equal to single.
Preferably, width of the distance of the mobile platform single movement more than or equal to the rectangular slot.
Preferably, the thickness of the light barrier is less than 0.2mm.
Preferably, the shutter is arranged between the diaphragm and the beam splitter.
Preferably, reflecting mirror described in two sides is provided with angle regulating unit, and the angle regulating unit is used to adjust described
The angle of reflecting mirror.
Preferably, the laser diode specifically adopts wavelength X for the blue light laser diode of 405nm.
Preferably, the aperture D of the diaphragm meets relational expression：2gLc/ λ ＜ D/cos θ, the width L of the reflecting mirror meet
Relational expression：L>D/sin (67.5 ° of-θ/2), wherein：G is screen periods, and λ is the wavelength of the light source, LcFor two pole of the laser
The coherence length of pipe, θ are the half of the angle penetrated between the dual-beam in the smooth gate substrate.
Compared with prior art, the beneficial effects of the utility model are：The system of holographic grating array of the present utility model
Laser diode is adopted in making device as light source, it is convenient to omit beam expanding lens, spatial filter, optical resonator, membrance selection cavity etc.
Costly, complicated external component, the light beam launched by laser diode first pass around collimating mirror and diaphragm, then using beam splitter
After being split, reflected mirror interferes to form interference field after changing the direction of propagation respectively, is being arranged on the grating of interference field
Holographic grating is formed on substrate；And by shutter control time of exposure and the traveling time of light gate substrate so that in light gate substrate
On can form holographic grating array, such that it is able to be applied to one-dimensional grating chi；The producing device of the holographic grating array is solved
Existing laser interferance method make the high cost that the device of grating has, complex structure, it is bulky the problems such as, with cost
Low, instrument and equipment is simple, compact in design the advantages of.
In further scheme, the light barrier being fixedly installed is provided with grating surface, light barrier is provided with rectangle
Slit so that the holographic grating array of making is more neat；And, in mobile platform moving grating substrate, each movement
Distance need to only be more than or equal to the width of rectangular slot, and manufacture method is easy, wherein the holographic grating array produced can
Double-reading head grating scale is applied to, the reading blind zone problem that array pitch causes is solved well.
The holographic grating of the screen periods specified in further scheme, is made, need to only be adjusted and be penetrated in light gate substrate
On dual-beam between angle, wherein can pass through adjust two-face mirror angle, or by adjust light source project
Incident angle of the light beam on beam splitter is capable of achieving to adjust the angle penetrated between the dual-beam in light gate substrate.And, light
Late aperture and mirror width conform to a predetermined condition can be so that the width of the grating formed in light gate substrate be Lloyd's mirror knot
The twice of structure.
Description of the drawings
Fig. 1 is the structural representation of the producing device of the holographic grating array of this utility model preferred embodiment；
Fig. 2 is the holographic optical that the producing device of the holographic grating array by this utility model preferred embodiment is made
Grid array is applied to the schematic diagram of double-reading head grating scale.
Specific embodiment
Below against accompanying drawing and with reference to preferred embodiment the utility model is described in further detail.
As shown in figure 1, the producing device of the holographic grating array of this utility model preferred embodiment includes light source 1, collimation
Mirror 2, diaphragm 3, shutter 4, beam splitter 5, the first reflecting mirror 6, the second reflecting mirror 7, light barrier 8, light gate substrate 9 and mobile platform
10, light gate substrate 9 is coated with the glass substrate 91 of photoresist 92, and light source 1 adopts laser diode, wherein light source 1, collimating mirror 2
The direction advanced along light beam with diaphragm 3 co-axial alignment successively, beam splitter 5 are arranged in light path of the light beam after diaphragm 3, beam splitting
For light beam is reflected into two light beams, shutter 4 is arranged between light source 1 and beam splitter 5 and coaxial with light beam mirror 5, wherein at this
In embodiment, shutter 4 is arranged between diaphragm 3 and beam splitter 5；First reflecting mirror 6 and the second reflecting mirror 7 are separately positioned on beam splitting
In the light path of two light beams after the reflection of mirror 5, the first reflecting mirror 6 and the second reflecting mirror 7 are arranged by axle axial symmetry of beam splitter 5, light
Gate substrate 9 is installed on a mobile platform 10, and light gate substrate 9 is located at interference field, and further light gate substrate 9 is arranged on interference field most
At width.Light barrier 8 is provided with rectangular slot, and light barrier 8 is fixedly installed on above light gate substrate 9, and rectangular slot is correspondingly arranged at
Formed at the position of holographic grating；Wherein light barrier 8 can adopt the thin plate for being close to light gate substrate 9, gauge of sheet to be about
0.1mm (wherein gauge of sheet should be got over as thin as possible), the width of rectangular slot are less than or equal to the width of the holographic grating for being formed
Degree, wherein the width W of holographic gratingc=2gLc/ λ, g are screen periods, and λ is the wavelength of the light source；Wherein light beam passes through rectangle
Become rectangular light spot to be irradiated in light gate substrate 9 after slit, rectangular light spot size is approximately equal to the size of rectangular slot.
Wherein, shutter 4 adopts electronic shutter, the opening time of electronic shutter to be equal to when forming the single exposure of holographic grating
Between, the shut-in time of electronic shutter is equal to the time needed for the movement of 10 single of mobile platform.
In implementing, two light beams reflect to form dual-beam and penetrate respectively through the first reflecting mirror 6 and the second reflecting mirror 7
In light gate substrate 9, half θ of the angle penetrated between the dual-beam in light gate substrate 9 should meet relational expression：G=λ/2sin
θ, wherein：G is screen periods, and λ is the wavelength of the light source, it is therefore desirable to make the grating of predetermined screen periods, only needs to adjust
Angle between dual-beam；And be to adjust the angle between dual-beam, the light beam of the injection of light source 1 on the one hand can be adjusted in beam splitting
Incident angle on mirror 5, i.e., by adjust light source 1, the angle between collimating mirror 2 and the axle and beam splitter 5 of diaphragm 3, wherein this
When can fix the first reflecting mirror 6 and the second reflecting mirror 7 be vertically arranged with light gate substrate 9 respectively (i.e. now light beam relative to point
The angle of incidence of beam mirror 5 has played Main Function in screen periods are determined)；On the other hand the first reflecting mirror 6 and the can also be adjusted
The angle of two-mirror 7, you can be respectively provided with angle regulating unit on the first reflecting mirror 6 and the second reflecting mirror 7, to adjust
One reflecting mirror 6 and the second reflecting mirror 7 respectively with the angle between light gate substrate 9, wherein the first reflecting mirror 6 and the second reflecting mirror 7
Should also be to arrange by axle axial symmetry of beam splitter 5 after adjusted, now, the regulation of light path is very convenient, and can be with fixed beam
Relative to the angle of incidence of beam splitter 5, such as 45 °.
In a still further embodiment, light source 1 coherence length to raster width LcRestriction effect have precedence over light
Under the conditions of beam diameter, mirror width, the width W of the holographic grating that single is formed in light gate substrate 9cIt is Lloyd's mirror structure
Twice, concrete structure formula is：Wc=2gLc/ λ, wherein g are screen periods, and λ is the wavelength of light source 1.Wherein specifically, in diaphragm
Aperture D (namely beam diameter) meet relational expression：2gLc/ λ ＜ D/cos θ, the width L of reflecting mirror meet relational expression：L>D/
During sin (67.5 ° of-θ/2), the coherence length of light source 1 is to raster width LcRestriction effect have precedence over beam diameter, reflecting mirror width
Degree.
Following combination instantiations make holographic grating to the producing device using holographic grating array of the present utility model
Array is further described.
(1) glass substrate 91 is cleaned first, glass substrate 91 is placed in ultrasonic washing unit and is cleaned, then use second successively
Alcohol, ethanol, deionized water cleaning, are finally dried up with nitrogen, are placed in being dried on dehydrator；Photoresist 92 is then spin coated onto, by one
Certainty ratio prepares photoresist solution, and substrate of glass 91 is placed on spin coater, choose the photoresist solution prepared on a small quantity drip in
On glass substrate 91, setting Reasonable Parameters carry out spin coating, it is ensured that photoresist solution can equably be covered in 91 surface of glass substrate,
Preparation forms light gate substrate 9.
(2) producing device as shown in Figure 1 is built, is built according to the explanation of above-mentioned producing device, form such as Fig. 1
Shown light path, strictly guarantees the accuracy of light path, is that light source 1 processes specific fixing device, while providing stable for which
Current source, and the power of laser instrument can be adjusted by adjusting current source；Wherein light source 1 adopts wavelength X for 405nm in this example
Blue light laser diode.
(3) interference fringe is detected, as interference fringe naked eyes are difficult to differentiate, and effectively interferes width extremely narrow (about 5mm),
Place an object lens (100 times of amplification) to have checked whether that interference field is formed at interference field, if nothing, repeat step (2) relaying
It is continuous to adjust light path；If having, the width of rectangular slot light barrier 8 on is determined according to the actual requirements, and the width is less than or equal to complete
The width of breath grating, then carries out next step.
(4) by step (1), the glass substrate 91 of resist coating 92 is placed in interference field the widest part, and the light gate substrate 9
Install on a mobile platform 10, follow mobile platform 10 to move；And light barrier 8 is fixedly installed on the top of light gate substrate 9, no
Light gate substrate 9 and mobile platform 10 is followed to move.
(5) suitable time of exposure (Et) is chosen, sets opening time (Ot), the shut-in time (Ct) of shutter 4, and set
Single of the opening time (Ot) of the translational speed and traveling time (Mt) of mobile platform 10, wherein shutter 4 equal to holographic grating
Time of exposure (Et), the traveling time (Mt) of shut-in time (Ct) of shutter 4 equal to mobile platform 10, and mobile platform 10
Translational speed * traveling time (Mt), namely single displacement is more than or equal to the width of rectangular slot.
(6) it is exposed development.Exposure flow process once is：Shutter opens (exposure), shutter close, and (mobile platform is moved
It is dynamic)；For several times, most glass substrate 91 is placed in developer solution and develops at last, can obtain after drying for repeated exposure mobile platform
One-dimensional holographic grating array, wherein as a example by making holographic grating of the screen periods as 2500nm, the producing device can make list
Grating of the secondary exposed width for 5mm, entire length (the as number of times * single exposure width of the movement of mobile platform 10) is up to 20mm
More than.
Holographic grating array is made by the producing device of the holographic grating array of this utility model preferred embodiment can be with
Be applied to double-reading head one-dimensional grating chi, wherein set when making holographic grating array the distance mobile every time of mobile platform 10 as
The width of L+ δ, wherein L for rectangular slot, δ strictly need not be controlled, i.e., so that the process for making holographic grating array is easier；
The holographic grating array of making is applied to into double-reading head one-dimensional grating chi, two read heads of the double-reading head one-dimensional grating chi
Between spacing be d, wherein d meets relational expression δ ＜ d ＜ 2L+ δ；Two read heads when the double-reading head one-dimensional grating chi works
The information of array grating is read simultaneously, and its spacing d may insure that at least one read head can effectively read holographic grating array
Information, i.e., at most have a read head be in reading blind area (δ regions).
As shown in Fig. 2 being that the producing device of holographic grating array of the present utility model is made holographic grating array application
In the schematic diagram of double-reading head one-dimensional grating chi, detection light is divided into two-beam after beam splitter 5, and light beam is through a quarter
It is irradiated to after wave plate 12 and transmissive diffraction grating 13 with reference to grating 15, another light beam is through quarter-wave plate 12 and transmission-type
The normal operation region (width L) of holographic grating array 14 is irradiated to after diffraction grating 13；Light beam finally returns back to detector 16,
Phase place change on detection comparator probe 16, you can check that holographic grating array 14 becomes relative to the displacement with reference to grating 15
Change, when certain Shu Guangzhao is mapped to the dead space (δ regions) of holographic grating array 14, i.e., phase place that cannot be on comparator probe 16 becomes
Change, it is invalid to measure.In this example will detection light by holes diaphragm 11 be divided into two-beam (solid line light path and dotted line light path in figure,
Spacing between the two-beam is more than δ and is less than 2L+ δ), you can to guarantee that at least a branch of luminous energy is irradiated to holographic grating array
14 normal operation region (width L), is not in dead space (δ regions) that two-beam is irradiated to holographic grating array 14,
Therefore the phase place change on comparator probe 16 can be detected always, check holographic grating array 14 relative to the position with reference to grating 15
Move change.
Using laser diode as light source in the producing device of holographic grating array of the present utility model, it is convenient to omit expand
The costly, complicated external component such as Shu Jing, spatial filter, optical resonator, membrance selection cavity, the light launched by laser diode
Beam first passes around collimating mirror and diaphragm, then after being split using beam splitter, the reflected mirror of difference occurs after changing the direction of propagation
Interference forms interference field, in the light gate substrate for being arranged on interference field forms holographic grating；And pass through shutter control time of exposure
It is with the traveling time of light gate substrate so that holographic grating array can be formed in light gate substrate, one-dimensional such that it is able to be applied to
Grating scale；The producing device of the holographic grating array solves existing laser interferance method and makes the cost that the device of grating has
Height, complex structure, it is bulky the problems such as, have the advantages that low cost, instrument and equipment be simple, compact in design.
Above content is with reference to specific preferred implementation further detailed description of the utility model, it is impossible to
Identification is of the present utility model to be embodied as being confined to these explanations.For this utility model person of ordinary skill in the field
For, without departing from the concept of the premise utility, some equivalent substitutes or obvious modification, and performance can also be made
Or purposes is identical, protection domain of the present utility model should be all considered as belonging to.
Claims (10)
1. a kind of producing device of holographic grating array, it is characterised in that including light source, collimating mirror, diaphragm, shutter, beam splitter,
Two-face mirror, light gate substrate and mobile platform, wherein the light source adopts laser diode, the light source, the collimating mirror
The direction advanced along light beam with diaphragm co-axial alignment successively, the beam splitter are arranged on the light beam after the diaphragm
Light path on, for the light beam is reflected into two light beams, the shutter is arranged on the light source with described point to the beam splitter
It is between Shu Jing and coaxial with the light beam；Reflecting mirror described in two sides be separately positioned on the reflection of described in beam splitter after two light beams
In light path, reflecting mirror described in two sides is arranged by axle axial symmetry of the beam splitter, and the smooth gate substrate is flat installed in the movement
On platform, and the smooth gate substrate is located at interference field.
2. producing device according to claim 1, it is characterised in that the shutter adopts electronic shutter, described electronic fast
The opening time of door is equal to the single exposure time for forming holographic grating, and the shut-in time of the electronic shutter is equal to the movement
Time needed for the movement of platform single.
3. producing device according to claim 1, it is characterised in that also including light barrier, the light barrier is provided with square
Shape slit, the light barrier are fixedly installed on the grating surface, and the rectangular slot is correspondingly arranged to form holographic optical
At the position of grid.
4. producing device according to claim 3, it is characterised in that the light barrier is using being close to the smooth gate substrate
Thin plate, the width of the rectangular slot are less than or equal to the width of the holographic grating that single is formed.
5. producing device according to claim 3, it is characterised in that the distance of the mobile platform single movement be more than or
Equal to the width of the rectangular slot.
6. producing device according to claim 3, it is characterised in that the thickness of the light barrier is less than 0.2mm.
7. producing device according to claim 1, it is characterised in that the shutter is arranged on the diaphragm with the beam splitting
Between mirror.
8. producing device according to claim 1, it is characterised in that reflecting mirror described in two sides is provided with angular adjustment list
Unit, the angle regulating unit are used for the angle for adjusting the reflecting mirror.
9. producing device according to claim 1, it is characterised in that the laser diode specifically adopt wavelength X for
The blue light laser diode of 405nm.
10. the producing device according to any one of claim 1 to 9, it is characterised in that the aperture D of the diaphragm meets and closes
It is formula：2gLc/ λ ＜ D/cos θ, the width L of the reflecting mirror meet relational expression：L>D/sin (67.5 ° of-θ/2), wherein：G is light
Grid cycle, λ is the wavelength of the light source, LcFor the coherence length of the laser diode, θ is to penetrate in the smooth gate substrate
The half of the angle between dual-beam.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201621069926.7U CN206057620U (en) | 2016-09-21 | 2016-09-21 | A kind of producing device of holographic grating array |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201621069926.7U CN206057620U (en) | 2016-09-21 | 2016-09-21 | A kind of producing device of holographic grating array |
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| Publication Number | Publication Date |
|---|---|
| CN206057620U true CN206057620U (en) | 2017-03-29 |
Family
ID=58366946
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| Application Number | Title | Priority Date | Filing Date |
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| CN201621069926.7U Withdrawn - After Issue CN206057620U (en) | 2016-09-21 | 2016-09-21 | A kind of producing device of holographic grating array |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106226854A (en) * | 2016-09-21 | 2016-12-14 | 清华大学深圳研究生院 | A kind of producing device of holographic grating array |
-
2016
- 2016-09-21 CN CN201621069926.7U patent/CN206057620U/en not_active Withdrawn - After Issue
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106226854A (en) * | 2016-09-21 | 2016-12-14 | 清华大学深圳研究生院 | A kind of producing device of holographic grating array |
| CN106226854B (en) * | 2016-09-21 | 2018-08-17 | 清华大学深圳研究生院 | A kind of producing device of holographic grating array |
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| GR01 | Patent grant | ||
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Granted publication date: 20170329 Effective date of abandoning: 20180817 |