CN1273798C - Path_matching path type interferometer device - Google Patents
Path_matching path type interferometer device Download PDFInfo
- Publication number
- CN1273798C CN1273798C CN 200410037274 CN200410037274A CN1273798C CN 1273798 C CN1273798 C CN 1273798C CN 200410037274 CN200410037274 CN 200410037274 CN 200410037274 A CN200410037274 A CN 200410037274A CN 1273798 C CN1273798 C CN 1273798C
- Authority
- CN
- China
- Prior art keywords
- path
- luminous intensity
- light
- detected
- optical system
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Landscapes
- Instruments For Measurement Of Length By Optical Means (AREA)
Abstract
The invention conveniently and optically adjusts the contrast of interference fringes according to different reflectivities of the surfaces to be detected, by providing a light intensity adjusting optical system in a path-match route. The light intensity adjusting optical system 30 selectively switches one of three ND filters, having different light transmittances that are arranged on nearly concentric circles at the center of a rotating axis 31, and positions it on a first route of a path-matching path 20, thereby adjusting the ratio of the light intensities of two light fluxes passing through the first path and a second route, respectively. A compensation optical system 40 inserts to the second route a compensation plate of which refractive index and thickness are set in almost the same manner as that of the ND filter, thereby compensating the difference in the optical path lengths between two paths cases that vary, when the ND filter is inserted and when it is pulled out.
Description
Technical field
The present invention relates to a kind of interferometer, particularly relate to a kind of have the light beam from light source is divided into two light beams, and after making these two light beams the optical path difference by each other being adjusted to two paths of 2 times of detected optical range of the reference field that is equivalent to interferometer and detected body respectively, close route matching (Pathmatch) the path type interferometer of route matching (Path match) the path portion of ripple and output.
Background technology
In known techniques, but Fei Zuo (Fizeau) the type interferometer of the light source that interference capabilities such as lift-launch LASER Light Source are good, but can between reference field and detected, vacate and use the interference distance corresponding intervals of light source, obtain enough work spaces, so be widely used as wieldy interferometer.But, such to parallel plane glass, having non-detected the detected body substantially parallel with detected measures when resolving, but owing to use the interference distance of light source long, so except the interference of light from reference field and detected, also producing respectively has from reference field and non-detected (on detected body with a face detected opposite side) and detected and non-detected the interference of light.Usually, except forming noise, be difficult to accurately detected shape be measured from the interference fringe reference field and detected 's the interference fringe that the interference of light produced.
As a kind of technology that solves the problem of this luxuriant and rich with fragrance assistant type interferometer, the present patent application people has disclosed a kind of as following patent documentation 1 described route matching path type interferometer.As utilize this route matching path type interferometer, but the interference distance of measuring light can be set at less than a fixed length, and the route matching path that a part of measuring light is made a circulation is set, except utilize the mensuration light do not make a circulation and directly to advance from detected reflected light, beyond the catoptrical situation from reference field of the mensuration light that makes a circulation, can not produce the interference of light, so can obtain not having the interference fringe image clearly of noise with open-and-shut formation.
[patent documentation 1]
The spy of Japanese Patent Laid Open Publication opens flat 9-21606 communique.
Yet although usually also utilize 1 interferometer that the detected body of majority kind is measured parsing, the kind because of detected body differs widely the reflectivity of detected face sometimes. By in from the reverberation of detected face and the interference fringe that produces from the reverberation of datum level, if each catoptrical luminous intensity is in identical level, then contrast is good, is easy to carry out interference fringe and resolves. Therefore, in known techniques, be most datum plates that differ from one another by the reflectivity of preparing datum level in advance, and exchange datum plate according to the difference of the reflectivity of detected face, thereby seek the contrast adjustment of interference fringe.
But, exchange heavy datum plate and be not easy, all need the inclination of the datum level in the optical system is adjusted etc. the problem of workability aspect when having each exchange datum plate. And the datum plate of preparing a plurality of high prices obviously increases burden economically. So, generally be to make the exchange of datum plate remain on Min., to what the difference of reflectivity of each detected face, process by the images such as tonal range that in photographic system, carry out modified-image, and the contrast of interference fringe is adjusted.
But, in order to carry out high-precision dissection process according to captured interference fringe image, preferably do not rely on this image to process, and carry out optic contrast adjustment. Therefore, need a kind of can be according to the difference of the reflectivity of detected face, and the interferometer of interference fringe degree of comparing being adjusted from the optics more easily.
This shows that above-mentioned existing interferometer still has many defectives, and demands urgently further being improved.In order to solve the problem that interferometer exists, relevant manufacturer there's no one who doesn't or isn't seeks solution painstakingly, but do not see always that for a long time suitable design finished by development, and common product does not have appropriate structure to address the above problem, this obviously is the problem that the anxious desire of relevant dealer solves.
Because the defective that above-mentioned existing interferometer exists, the inventor is based on being engaged in this type of product design manufacturing abundant for many years practical experience and professional knowledge, actively studied innovation, in the hope of founding a kind of novel route matching path type interferometer, can improve general existing interferometer, make it have more practicality.Through constantly research, design, and after studying sample and improvement repeatedly, create the present invention who has practical value finally.
Summary of the invention
The objective of the invention is to, overcome the defective that existing interferometer exists, and provide a kind of new route matching path type interferometer, technical matters to be solved is to make it can be according to the difference of detected reflectivity, and can from optics, the contrast of interference fringe be adjusted easily, thereby be suitable for practicality more.
The object of the invention to solve the technical problems realizes by the following technical solutions.A kind of route matching path type interferometer according to the present invention's proposition, it has the light beam from light source is divided into two light beams, and after making these two light beams the optical path difference by each other being adjusted to two paths of 2 times of detected optical range of the reference field that is equivalent to interferometer and detected body respectively, these two light beams are closed the route matching path portion of ripple and output; The aforementioned reference field of light beam irradiates that formation is exported this route matching path portion, and aforementioned detected the form that the light beam irradiates that seen through this reference field and this reference field are separated, and the interference fringe according to the interference of the light wave face that utilizes this reference field to reflect and this detected light wave face that is reflected produces obtains this corrugated information of detected; In aforesaid paths coupling path portion, be equipped with according to aforementioned reference field and each aforementioned detected reflectivity, the luminous intensity that the ratio of each luminous intensity of aforementioned two light beams that this route matching path portion is exported is adjusted is adjusted optical system.
The object of the invention to solve the technical problems also can be applied to the following technical measures to achieve further.
Aforesaid route matching path type interferometer, wherein said detected body is a transparent parallel, be set less than the thickness of aforementioned transparent parallel but can be interference distance, but be 2 times low coherent light bundle of optical range by the aforementioned light beam that aforementioned light source is exported.
Aforesaid route matching path type interferometer, wherein said luminous intensity is adjusted optical system configurations in the way, at least one path in aforementioned two paths, and will change to the luminous intensity that this luminous intensity is adjusted the light beam that optical system imports and export.
Aforesaid route matching path type interferometer, wherein said luminous intensity are adjusted optical system the ratio of each luminous intensity of aforementioned two light beams are carried out variable adjustment.
Aforesaid route matching path type interferometer, wherein said luminous intensity is adjusted optical system and is adopted by being equipped with most ND light filters, and selectively change this majority ND light filter and be located on the aforesaid paths, thereby change the formation of the ratio of aforementioned each luminous intensity.
Aforesaid route matching path type interferometer, it also is equipped with an aforementioned majority drive unit that the ND light filter is selectively changed, and the driving control device that this drive unit is controlled.
Aforesaid route matching path type interferometer, wherein said luminous intensity is adjusted optical system and can be set in aforementioned two paths on the way with plugging, and these two paths in addition on the way, can be provided with compensation optical system with plugging, be used to compensate when this luminous intensity is adjusted optical system and is inserted into and the optical path difference in these two paths of changing when being pulled out.
The present invention compared with prior art has tangible advantage and beneficial effect.By above technical scheme as can be known, in order to reach aforementioned goal of the invention, major technique of the present invention thes contents are as follows:
The present invention proposes a kind of route matching path type interferometer, it has the light beam from light source is divided into two light beams, and after making these two light beams the optical path difference by each other being adjusted to two paths of 2 times of detected optical range of the reference field that is equivalent to interferometer and detected body respectively, these two light beams are closed the route matching path portion of ripple and output; The aforementioned reference field of light beam irradiates that formation is exported this route matching path portion, and aforementioned detected the form that the light beam irradiates that seen through this reference field and this reference field are separated, and the interference fringe according to the interference of the light wave face that utilizes this reference field to reflect and this detected light wave face that is reflected produces obtains this corrugated information of detected; In aforesaid paths coupling path portion, be equipped with according to aforementioned reference field and each aforementioned detected reflectivity, the luminous intensity that the ratio of each luminous intensity of aforementioned two light beams that this route matching path portion is exported is adjusted is adjusted optical system.
In the present invention, aforementioned detected body is a transparent parallel, is set less than 2 times the low coherent light bundle of the thickness of aforementioned transparent parallel (but being optical range) but can be interference distance by the aforementioned light beam that aforementioned light source is exported.
Aforementioned luminous intensity is adjusted optical system can be by for example resembling neutral filter (Neutral dcnsityfilter, the ND light filter) and Polarizer such, be disposed at least one path way in aforementioned two paths, and will adjust the optical component formation that the luminous intensity of the light beam that optical system imports changes and export to this luminous intensity.
And, aforementioned luminous intensity adjust optical system adopt a kind of can carry out the ratio of each luminous intensity of aforementioned two light beams variable adjustment (for example, that the ratio of each luminous intensity is carried out variable adjustment most stages and carry out variable adjustment continuously) for good.
In this case, aforementioned luminous intensity is adjusted optical system and can be adopted by being equipped with most ND light filters, and selectively changes this majority ND light filter and be located on the aforesaid paths, thereby changes the formation of the ratio of aforementioned each luminous intensity.
In addition, also can be equipped with an aforementioned majority drive unit that the ND light filter is selectively changed and driving control device that this drive unit is controlled.
And, also can adopt and make aforementioned luminous intensity adjustment optical system can be arranged at aforementioned two paths on the way with plugging, and these two paths in addition on the way, can compensation optical system be set with plugging, be used to compensate when this luminous intensity is adjusted optical system and is inserted into and the formation of the optical path difference in these two paths of changing when being pulled out.
In addition, above-mentioned " can plug " comprises the whole pluggable situation of aforementioned luminous intensity adjustment optical system or aforementioned compensation optical system, or the pluggable situation of their part.
By technique scheme, route matching of the present invention path type interferometer has following advantage at least:
1, by utilizing this luminous intensity to adjust optical system, ratio to each luminous intensity of above-mentioned two light beams is adjusted, can adjust the ratio of the luminous intensity of the luminous intensity of reference field institute beam reflected and detected institute's emitted light beams like a cork, so can carry out the contrast adjustment of interference fringe from the optics easily.
2, particularly by the luminous intensity that makes reference field institute beam reflected, be adjusted each other about equally with the luminous intensity of detected institute's beam reflected, can make the contrast of interference fringe good, resolve so can carry out the mensuration of interference fringe accurately.
In sum, the route matching path type interferometer of special construction of the present invention, it can be according to the difference of detected reflectivity, and from optics the contrast of interference fringe is adjusted easily.It has above-mentioned many advantages and practical value, and in like product, do not see have similar structural design to publish or use and really genus innovation, no matter it structurally or bigger improvement all arranged on the function, have large improvement technically, and produced handy and practical effect, and more existing interferometer has the multinomial effect of enhancement, thus be suitable for practicality more, and have the extensive value of industry, really be a new and innovative, progressive, practical new design.
Above-mentioned explanation only is the general introduction of technical solution of the present invention, for can clearer understanding technological means of the present invention, and can be implemented according to the content of instructions, below with preferred embodiment of the present invention and conjunction with figs. describe in detail as after.
Description of drawings
Fig. 1 is that the summary of the route matching path type interferometer of the 1st example of the present invention constitutes synoptic diagram.
Fig. 2 is the summary formation synoptic diagram that luminous intensity shown in Figure 1 is adjusted optical system.
Fig. 3 is that the summary of compensation optical system shown in Figure 1 constitutes synoptic diagram.
Fig. 4 is that the summary of the route matching path type interferometer of the 2nd example of the present invention constitutes synoptic diagram.
Fig. 5 is that the summary of the route matching path type interferometer of the 3rd example of the present invention constitutes synoptic diagram.
1: light source 2: collimator lens
3: divergent lens 4: half prism
4a: semi-transparent minute surface 5: collimator lens
6: datum plate 6a: reference field
7: detected body (transparent parallel) 7a: detected
7b: non-detected 8: mounting surface
9: imaging len 10: video camera
11: computing machine (driving control device) 12: graphical representation portion
13: input media 14,15: motor (drive unit)
16,17: motor driver 20: route matching path portion
21,22: half prism 21a, 22a: semi-transparent minute surface
23,24: completely reflecting mirror
30,30A, 30B: luminous intensity is adjusted optical system
31,31A: turning axle 32: finger plate
33: the 34a of circular open portion～34c:ND light filter
40: compensation optical system 41: turning axle
42: finger plate 43: circular open portion
44: compensating plate Z: optical axis
T1: the thickness of detected body
Embodiment
Below in conjunction with accompanying drawing and preferred embodiment, to route matching path its embodiment of type interferometer, structure, feature and the effect thereof that foundation the present invention proposes, describe in detail as after.
Below, utilize diagram that example of the present invention is described.
＜the 1 example 〉
See also Fig. 1 to shown in Figure 3, Fig. 1 is the generalized schematic about the route matching path type interferometer of the 1st example of the present invention, Fig. 2 is the generalized schematic that luminous intensity shown in Figure 1 is adjusted optical system, and Fig. 3 is the generalized schematic of compensation optical system shown in Figure 1.Interferometer shown in Figure 1 be a kind of 1 that exported from light source, utilize collimator lens 2 to form on the light path of light beam of directional lights, the route matching path type interferometer of route matching path portion 20 is equipped with.
Above-mentioned route matching path portion 20 is included in two half prisms 21 that dispose to divergent lens 3 linearly extended the 1st paths from collimator lens 2,22, telling from the 1st path and at two half prisms 21, two completely reflecting mirrors 23,24 that dispose on the 2nd path that 22 are made a circulation.
In this route matching path portion 20,, be divided into through the light beam of this semi-transparent minute surface 21a with by this semi-transparent minute surface 21a right angle beam reflected from the light beam of collimator lens 2 semi-transparent minute surface 21a at half prism 21.The above-mentioned light beam that sees through semi-transparent minute surface 21a is along the 1st path incident half prism 22, and above-mentioned by semi-transparent minute surface 21a right angle beam reflected along the 2nd path, utilize above-mentioned completely reflecting mirror 23,24 by after the right angle reflection successively, the above-mentioned half prism 22 of incident.Then, in above-mentioned half prism 22, the part of the part of the light beam by the 1st path and the light beam by the 2nd path is closed ripple and output.
The light beam of exporting from half prism 22 is irradiated on the transparent datum plate 6 after beam diameter is enlarged.A part that incides the light beam in the datum plate 6 is reflected by reference field 6a, but remaining light beam can see through reference field 6a, shines on the detected body 7 of institute's mounting on the mounting surface 8.
Interfere each other from the reference field 6a institute beam reflected (light wave face) of datum plate 6 with from detected the 7a institute beam reflected (light wave face) of detected body 7.Semi-transparent minute surface 4a at half prism 4 is reflected by the right angle, and forms interference fringe image by imaging len 9 on the CCD element in video camera 10.According to utilizing this CCD element to be carried out the interference fringe image information of opto-electronic conversion, can be in computing machine 11 surface configuration of detected 7a etc. be measured parsing, and at cathode-ray tube (CRT) (Cathode ray tube CRT) shows interference fringe image in the graphical representation portion 12 of Denging.
In addition, above-mentioned route matching path portion 20, the optical path difference of its 1st path (optical path length L1) and the 2nd path (optical path length L2=I1+I2+I3) is set to 2 times of optical range L of detected 7a of the reference field 6a that is substantially equal to datum plate 6 and detected body 7.By this,, and be equal to each other by the optical path length of reference field 6a beam reflected by detected 7a reflection and see through the optical path length of the light beam of reference field 6a by the 1st path by the 2nd path.
Utilize this formation,, also can measure accurately shape of detected 7a etc. even detected body is sheets of glass and transparent parallels such as plastic plate, quartz plate.Promptly, penetrate light emitting diode (Super luminescent diode by surpassing the width of cloth, SLD), use as light source 1 in the low coherent light source of Halogen lamp LED or high-pressure mercury-vapor lamp etc. (but for example interference distance is 1 μ m), but and set the interference distance of its light beam of exporting less than 2 times of transparent parallel thickness t 1, thereby can not produce, and the interference of light of detected 7a and non-detected 7b from the reference field 6a of datum plate 6 and non-detected the 7b (inner face of detected body) of detected body 7.In addition, about effect of this route matching path portion etc., at length disclose in the patent documentation of mentioning in front 1, it describes omission in detail.
The 1st example is characterised in that, in route matching path portion 20, is included in luminous intensity adjustment optical system 30 that is disposed on the 1st path and the compensation optical system 40 that is disposed on the 2nd path.
See also shown in Figure 2ly, luminous intensity is adjusted optical system 30, is included in the finger plate of rotatably being supported around the turning axle 31 32, and on this finger plate 32, being formed with 4 be the circular open portion 33 that the center also roughly disposes on concentric circles with turning axle 31.On 3 in these 4 circular open portions 33, maintain ND light filter (neutral filter) 34a～34c that light transmission rate differs from one another respectively, remaining 1 is naked thing state (open state).
This luminous intensity is adjusted optical system 30 employings 1 in 4 circular open portions 33 is changed selectively, and be located at formation on the 1st path of route matching path portion 20, the luminous intensity of the light beam by the 1st path is changed, the ratio of each luminous intensity of two light beams by the 1st path and the 2nd path is respectively adjusted in addition, and it is roughly the same each other that 3 ND light filter 34a～34c are set to each refractive index and thickness.
On the other hand, compensation optical system 40 is included in the finger plate of rotatably being supported around the turning axle 41 42 as shown in Figure 3, and on this finger plate 42, being formed with two is the circular open portion 43 that the center also roughly disposes on concentric circles with turning axle 41.Maintain on 1 in these two circular open portions 43 refractive index and thickness be set with the roughly the same compensating plate 44 of above-mentioned ND light filter 34a～34c, another is naked thing state.
When these compensation optical system 40 employings any in above-mentioned ND light filter 34a～34c is inserted on the 1st path, compensating plate 44 is inserted on the 2nd path, 34a～34c is pulled out from the 1st path at the ND light filter, and when being inserted into the circular open portion 33 of naked thing on the 1st path, compensating plate 44 extracted from the 2nd path and the circular open portion 43 of naked thing is inserted into formation on the 2nd path, the optical path difference in two paths that change in the time of by this, can compensating when ND light filter 34a～34c is inserted into and be pulled out.
In addition, ND light filter 34a～34c and compensating plate 44 are in order to get rid of the catoptrical harmful effect at its each face (surface and the back side), under the state that is disposed on the 1st, the 2nd path, adopt the formation make respectively in the face of the optical axis oblique, or be implemented in each face and form antireflection film etc. and be treated to good.
As shown in Figure 1, above-mentioned luminous intensity is adjusted optical system 30 and above-mentioned compensation optical system 40 and is adopted by driven formation as the motor 14,15 of drive unit and respectively.These motor 14,15 are respectively by motor driver 16,17, be connected with computing machine 11 as driving control device, and the control signal of utilizing this computing machine 11 to be sent are driven control.On computing machine 11, be connected with input medias 13 such as keyboard and switch.This input media 13 is directly imported the numeric data of the reflectivity of above-mentioned detected 7a by the operating personnel of for example interferometer, or to which can select conversion operations such as pushed by a preassigned majority switching button according to the reflectivity values scope of detected 7a, and be operated.
Above-mentioned luminous intensity is adjusted optical system 30 and above-mentioned compensation optical system 40, is driven by motor 14,15 respectively by computing machine 11.As mentioned above, luminous intensity is adjusted 1 in optical system 30 its 4 circular open portions 33, is converted selectively and is inserted into configuration on the 1st path of route matching path portion 20.Which be inserted on the 1st path about in 4 circular open portions 33, can be by above-mentioned the 1st path and by the luminous intensity P1 of above-mentioned detected 7a reflected beams, with by above-mentioned the 2nd path and by the luminous intensity P2 of said reference face 6a reflected beams each other under about equally the condition, and be determined in advance.And, luminous intensity is adjusted each transmitance of 3 ND light filter 34a～34c in the optical system 30, consider the reflectivity etc. of the transmitance of the transmitance of each optics that route matching path portion 20 is disposed and reflectivity, said reference face 6a and reflectivity, above-mentioned detected 7a and sets.
For example, be assumed to be luminous intensity and adjust the circular open portion 33 of naked thing of optical system 30 in the situation that is inserted into configuration (on the 2nd path, the circular open portion 43 of the naked thing of compensation optical system 40 is inserted into configuration at this moment) on the 1st path.At this moment, be used to make above-mentioned two luminous intensity P1, P2 about equally condition each other, utilize transmitance Thm and the transmitance Tr of reflectivity Rhm, said reference face 6a and the reflectivity Rs of reflectivity Rr, above-mentioned detected 7a of the semi-transparent minute surface 21a of above-mentioned half prism 21, represent by following formula (1).In addition, make transmitance and the reflectivity of the semi-transparent minute surface 22a of above-mentioned half prism 22 be respectively 0.5, each reflectivity of above-mentioned completely reflecting mirror 23,24 is respectively 1.
Thm×Tr×Rs×Tr＝Rhm×Rr……(1)
Suppose that luminous intensity adjusts among the ND light filter 34a～34c of optical system 30 any in the situation that is inserted into configuration (on the 2nd path, the compensating plate 44 of compensation optical system 40 is inserted into configuration at this moment) on the 1st path.At this moment, be used to make above-mentioned two luminous intensity P1, P2 about equally condition each other, utilize the transmitance Tnd of ND light filter to represent by following formula (2).In addition, in order to oversimplify, the transmitance that makes above-mentioned compensating plate 44 is 1.
Thm×Tnd×Tr×Rs×Tr＝Rhm×Rr……(2)
Then, for example the detected body of being measured is divided into most kinds by the difference of its reflectivity of detected, and detected reflectivity substitution following formula (1) of the detected body of will be the most frequent determined kind, determine the transmitance Thm of semi-transparent minute surface 21a and transmitance Tr and the reflectivity Rr of reflectivity Rhm, reference field 6a with the condition that satisfies following formula (1).And, with each reflectivity of detected of the detected body of other kind substitution following formula (2) (in the 1st embodiment, can reach 3 kinds) respectively, and with each transmitance decision of above-mentioned ND light filter 34a～34c for satisfying the value of following formula (2) when the time comes.Then, when the detected body of these other kinds was measured, ND filter configuration that will be corresponding with this reflectivity of detected was (dispose compensating plate 44 this moment on the 2nd path) on the 1st path.By this, can be according to the reflectivity of detected 7a, will by detected 7a reflection and see through reference field 6a light beam luminous intensity and be adjusted into each other about equally by the luminous intensity of reference field 6a beam reflected, can make the contrast of interference fringe good.
In addition, following formula (1), (2) also can strictly not form equation.For example, in various,, also can make the contrast of interference fringe enough good even the value on both sides produces about 10% error.
And, above-mentioned luminous intensity is adjusted optical system 30 and compensation optical system 40, for on concentric circles, having most peristomes, and utilize the rotation to move and carry out the rotary type of the configuration transitions of each peristome, on straight line, have a this majority peristome but also can be, and utilize straight line to move and carry out the reciprocating action type of the configuration transitions of each peristome.And the shape of peristome and number also can take the circumstances into consideration to change.
Perhaps, also can utilize rotation level ND or rotation Polarizer to constitute luminous intensity and adjust optical system 30, the luminous intensity that makes output beam changes continuously to the ratio of the luminous intensity of input beam.In this case, to the difference of detected reflectivity, can tackle in further detail.
And, in above-mentioned example, be that reflectivity with detected 7a is known as prerequisite, but, also can in interferometer, organize and go into the mechanism that the reflectivity of detected 7a is measured in order also to tackle the reflectivity condition of unknown of detected 7a.In addition, also can adopt reflectivity, luminous intensity adjustment optical system 30 and compensation optical system 40 are carried out self-adjusting formation according to detected the 7a that is measured.
＜the 2 example 〉
Seeing also shown in Figure 4ly, is the generalized schematic of the route matching path type interferometer of the 2nd example of the present invention.Below, describe about the 2nd example of the present invention.In Fig. 4, to the identical inscape of above-mentioned the 1st example, pay with Fig. 1 in the used identical symbol of symbol, and omit its detailed explanation.
The 2nd example is characterised in that in route matching path portion 20, to have the luminous intensity that is disposed on the 2nd path and adjust optical system 30A.It is same that the luminous intensity of this luminous intensity adjustment optical system 30A and above-mentioned the 1st example is adjusted optical system 30, on the concentric circles that with turning axle 31A is the center, have most circular open portions (diagram is omitted), and in these most circular open portions, have the ND light filter (refractive index each other about equally) that transmitance differs from one another respectively.Adjust the different place of optical system 30 with the luminous intensity of above-mentioned the 1st example and be there is not the circular open portion of naked thing.
Promptly, in the 2nd example, in the ND filter configuration under the state on the 2nd path, the optical path difference of the 1st path (optical path length L1) and the 2nd path (optical path length L2=I1+I2+I3), be set with 2 times of the optical range L of detected 7a of the reference field 6a of datum plate 6 and detected body 7 about equally.Therefore, there is no need to be provided in the compensation optical system 40 that is used as necessary device in the 1st example, can make device constitute summary.
In addition, luminous intensity is adjusted the transmitance of each ND light filter of optical system 30A, can set according to the 1st example.And, also can make luminous intensity adjust optical system 30A be above-mentioned reciprocating action type and utilize rotation level ND or rotation Polarizer.
And, also can constitute luminous intensity and adjust optical system 30A, and this ND light filter can be plugged on the 2nd path and constitute, or may be exchanged for other different ND light filter of light transmission rate by 1 ND light filter with certain light transmission rate.
＜the 3 example 〉
Seeing also shown in Figure 5ly, is the generalized schematic of the route matching path type interferometer of the 3rd example of the present invention.In Fig. 5, to the identical inscape of above-mentioned the 1st example, pay with Fig. 1 in the used identical symbol of symbol, and omit its detailed explanation.
The 3rd example is characterised in that, each reflectivity with benchmark face 6a and detected 7a, the luminous intensity that the ratio of each luminous intensity of two light beams by the 1st path and the 2nd path is respectively adjusted is adjusted optical system 30B, utilize the half prisms 21 that disposed in the route matching path portion 20 and constitute.Promptly, employing is on the semi-transparent minute surface 21a of half prism 21, impose the part of the light beam of being imported is seen through, and the coating of remaining beam reflection is handled, and change its coating characteristic (reflection/see through characteristic) by each reflectivity of benchmark face 6a and detected 7a, thereby can adjust the ratio of each luminous intensity of two light beams by the 1st path and the 2nd path respectively, and make the luminous intensity P2 that carries out the luminous intensity P1 of beam reflected and carry out beam reflected by the 1st path and by detected 7a constituting about equally each other by this by the 2nd path and by reference field 6a.
In order to make above-mentioned two luminous intensity P1, P2 each other about equally, the transmitance Thm of the semi-transparent minute surface 21a of above-mentioned half prism 21 and the desired condition of reflectivity Rhm, utilize the transmitance Tr of said reference face 6a and the reflectivity Rs of reflectivity Rr, above-mentioned detected 7a, represent by following formula (3).In addition, make transmitance and the reflectivity of the semi-transparent minute surface 22a of half prism 22 be respectively 0.5, each reflectivity of completely reflecting mirror 23,24 is respectively 1.
Thm×Tr×Rs×Tr＝Rhm×Rr……(3)
Here, as make Thm+Rhm=1, then transmitance Thm and reflectivity Rhm are represented by following formula (4), (5) respectively.
Thm＝Rr/(Tr×Rs×Tr+Rr)……(4)
Rhm＝(Tr×Rs×Tr)/(Tr×Rs×Tr+Rr)……(5)
Therefore, for example, work as Tr=0.96, Rr=0.04, during Rs=0.8, Thm is about 0.0515, and Rhm is about 0.9485.
In the 3rd example, most half prisms 21 that differ from one another by the coating characteristic of preparing semi-transparent minute surface 21a in advance, and exchange half prism 21 according to the reflectivity of detected 7a so that above-mentioned two luminous intensity P1, P2 each other about equally, thereby can make the contrast of interference fringe good.
More than example of the present invention is illustrated, but route matching of the present invention path type interferometer is not limited to above-mentioned example, and other various changes can be arranged.
For example, also the present patent application people can be opened the technology that is disclosed in the flat 11-23216 communique the spy of Japanese Patent Laid Open Publication uses in the present invention.Promptly, in above-mentioned each example, to be configured in through the 1st Polarizer of P polarisation between light source 1 and the half prism 21, making the Beam Transformation from light source 1 is the P polarisation, and, in the 2nd path of route matching path portion 20, insert λ/2 optical phase plates, will by the Beam Transformation in the 2nd path the S polarisation, and, and synthesize with the light beam of P polarisation form by the 1st path at half prism 22.And, between datum plate 6 and detected body 7, dispose λ/4 optical phase plates, detected 7a or non-detected the light that 7b reflected are converted to the P polarisation from the S polarisation, or are converted to the S polarisation from the P polarisation.Configuration sees through the 2nd Polarizer of S polarisation between video camera 10 and half prism 4, can only make S polarisation incident video camera 10.
By this, utilize route matching path portion 20 make optical path length be adjusted be equal to each other two light beams (by the 1st path by detected 7a reflected beams and by the 2nd path by reference field 6a reflected beams) all become the S polarisation, so that incident video camera 10 and the interference fringe image that carries the information of detected 7a made a video recording.On the other hand, differing from one another owing to optical path length and do not forming interference fringe, but form bias light and become in other light beam of the low reason of the contrast of interference fringe image, by the 1st path and by reference field 6a reflected beams and become the P polarisation, so not incident video camera 10 by the 2nd path and by reference field 7a or non-detected 7b reflected beams.Therefore, can improve the contrast of interference fringe image more.
In addition, also above-mentioned λ/2 optical phase plates can be disposed in the 1st path, and above-mentioned the 2nd Polarizer is replaced with Polarizer through the P polarisation.Perhaps, also can use Polarizer through the S polarisation as above-mentioned the 1st Polarizer, and about the 2nd Polarizer, with above-mentioned λ/when 2 optical phase plates are disposed in the 1st path for seeing through the Polarizer of S polarisation, with above-mentioned λ/when 2 optical phase plates are disposed in the 2nd path for seeing through the Polarizer of P polarisation.
And, in above-mentioned the 1st, the 2nd example, employing is adjusted the formation of the driving of optical system by the computer control luminous intensity, but also can be by operating personnel according to detected reflectivity and the manual switch luminous intensity is adjusted the ND light filter of optical system.
In above-mentioned example, be will be by the luminous intensity of reference field institute beam reflected, be adjusted into each other with luminous intensity that about equally situation describes as an example by detected institute's beam reflected, but also arbitrarily ratio each luminous intensity of these two light beams is adjusted.
And, when the detected body of determination object is opaque, also can utilize laser diode (Lascrdiode, LD) contour coherent light source, in this case, there is no need optical path difference, set to such an extent that be substantially equal to reference field and detected 's 2 times of optical range the 1st path in the portion of route matching path and the 2nd path.
In order to measure detected of dome shape, also can adopt the planar datum plate of instead of flat and use the formation that has with the reference lens of detected corresponding sphere.
And, in above-mentioned each example, represented respectively luminous intensity adjust optical system configurations in way, the 1st path (the 1st example), be disposed at (the 2nd example) in the way, the 2nd path, be disposed at the situation of the take-off point (the 3rd example) in the 1st path and the 2nd path, but also luminous intensity can be adjusted optical system configurations two places in the 1st path neutralizes the 2nd path way on the way, or add take-off point and be located at position, 3 place.
In addition, as utilize route matching of the present invention path type interferometer, adjust optical system by being equipped with luminous intensity, can not exchange datum plate and carry out the contrast adjustment of interference fringe, but also can adopt combination that the exchange datum plate is arranged and change the formation of function of the reflectivity of reference field.
As described above, route matching of the present invention path type interferometer is divided into two light beams at the light beam that light source is sent, and after making these two light beams the optical path difference by each other being adjusted to two paths of 2 times of optical ranges that are equivalent to reference field and detected respectively, close in the route matching path portion of ripple and output, be equipped with each reflectivity of benchmark face and detected, the luminous intensity that the ratio of each luminous intensity of two light beams is adjusted is adjusted optical system.
Adjust optical system by utilizing this luminous intensity, ratio to each luminous intensity of above-mentioned two light beams is adjusted, can adjust the ratio of the luminous intensity of the luminous intensity of reference field institute beam reflected and detected institute's emitted light beams like a cork, so can carry out the contrast adjustment of interference fringe from the optics easily.
Particularly the luminous intensity by the luminous intensity that makes reference field institute beam reflected and detected institute's beam reflected is adjusted each other about equally, can make the contrast of interference fringe good, resolves so can carry out the mensuration of interference fringe accurately.
The above, it only is preferred embodiment of the present invention, be not that the present invention is done any pro forma restriction, though the present invention discloses as above with preferred embodiment, yet be not in order to limit the present invention, any those skilled in the art, in not breaking away from the technical solution of the present invention scope, when the technology contents that can utilize above-mentioned announcement is made a little change or is modified to the equivalent embodiment of equivalent variations, in every case be the content that does not break away from technical solution of the present invention, according to technical spirit of the present invention to any simple modification that above embodiment did, equivalent variations and modification all still belong in the scope of technical solution of the present invention.
Claims (7)
1, a kind of route matching path type interferometer, it has the light beam from light source is divided into two light beams, and after making these two light beams the optical path difference by each other being adjusted to two paths of 2 times of detected optical range of the reference field that is equivalent to interferometer and detected body respectively, these two light beams are closed the route matching path portion of ripple and output; The aforementioned reference field of light beam irradiates that formation is exported this route matching path portion, and aforementioned detected the form that the light beam irradiates that seen through this reference field and this reference field are separated, and the interference fringe that produces according to the interference of the light wave face that utilizes this reference field to reflect and this detected light wave face that is reflected, obtain this corrugated information of detected, it is characterized in that:
In aforesaid paths coupling path portion, be equipped with according to aforementioned reference field and each aforementioned detected reflectivity, the luminous intensity that the ratio of each luminous intensity of aforementioned two light beams that this route matching path portion is exported is adjusted is adjusted optical system.
2, route matching according to claim 1 path type interferometer, it is characterized in that wherein said detected body is a transparent parallel, but the aforementioned light beam of being exported by aforementioned light source is set less than the thickness of aforementioned transparent parallel for interference distance, but is 2 times low coherent light bundle of optical range.
3, route matching according to claim 1 and 2 path type interferometer, it is characterized in that wherein said luminous intensity adjusts optical system configurations in the way, at least one path in aforementioned two paths, and will change to the luminous intensity that this luminous intensity is adjusted the light beam that optical system imports and export.
4, route matching according to claim 1 and 2 path type interferometer is characterized in that wherein said luminous intensity adjusts optical system the ratio of each luminous intensity of aforementioned two light beams is carried out variable adjustment.
5, route matching according to claim 4 path type interferometer, it is characterized in that wherein said luminous intensity adjustment optical system adopts by being equipped with most ND light filters, and selectively change this majority ND light filter and be located on the aforesaid paths, thereby change the formation of the ratio of aforementioned each luminous intensity.
6, route matching according to claim 5 path type interferometer is characterized in that it also is equipped with an aforementioned majority drive unit that the ND light filter is selectively changed, and the driving control device that this drive unit is controlled.
7, route matching according to claim 1 and 2 path type interferometer, it is characterized in that wherein said luminous intensity adjusts optical system and can be set in aforementioned two paths on the way with plugging, and these two paths in addition on the way, can be provided with compensation optical system with plugging, be used to compensate when this luminous intensity is adjusted optical system and is inserted into and the optical path difference in these two paths of changing when being pulled out.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2003141010A JP2004340901A (en) | 2003-05-19 | 2003-05-19 | Path-matching path interferometer |
| JP2003141010 | 2003-05-19 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1550751A CN1550751A (en) | 2004-12-01 |
| CN1273798C true CN1273798C (en) | 2006-09-06 |
Family
ID=33529548
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 200410037274 Expired - Fee Related CN1273798C (en) | 2003-05-19 | 2004-04-30 | Path_matching path type interferometer device |
Country Status (2)
| Country | Link |
|---|---|
| JP (1) | JP2004340901A (en) |
| CN (1) | CN1273798C (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102980599A (en) * | 2012-11-15 | 2013-03-20 | 浙江大学 | Precise length matching method in optical fiber interference optical paths |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1862313B (en) * | 2006-06-12 | 2010-08-25 | 霍尔国际有限公司 | Optical imaging system and optical detecting system with same |
| JP4810693B2 (en) * | 2007-02-09 | 2011-11-09 | 富士フイルム株式会社 | Lightwave interference measurement device |
| US10890839B1 (en) * | 2019-11-06 | 2021-01-12 | Himax Technologies Limited | Structured light imaging device |
-
2003
- 2003-05-19 JP JP2003141010A patent/JP2004340901A/en active Pending
-
2004
- 2004-04-30 CN CN 200410037274 patent/CN1273798C/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102980599A (en) * | 2012-11-15 | 2013-03-20 | 浙江大学 | Precise length matching method in optical fiber interference optical paths |
| CN102980599B (en) * | 2012-11-15 | 2015-01-14 | 浙江大学 | Precise length matching method in optical fiber interference optical paths |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2004340901A (en) | 2004-12-02 |
| CN1550751A (en) | 2004-12-01 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1159129C (en) | Laser machining apparatus | |
| CN100345013C (en) | Processing method for position and light of built-in tilt Bragg raster containing optical waveguide | |
| US7126751B2 (en) | Anti-reflection film and microscope having optical element with the same anti-reflection film applied thereto | |
| CN103688195A (en) | Optical filter and optical device | |
| US7728255B2 (en) | Spinning-type pattern-fabrication system and a method thereof | |
| CN101038166A (en) | An optical device and an optical lens | |
| JP2000199872A (en) | Illumination device and image display device | |
| CN1837893A (en) | Imaging system for projector and corresponding projector | |
| CN1881007A (en) | Optical path compensating device and optical pickup using the device | |
| JP2005236940A (en) | Linear light source for enhancing beaming light's focal range | |
| CN107965732A (en) | Optical unit | |
| CN1273798C (en) | Path_matching path type interferometer device | |
| CN1185524C (en) | Liquid crystal display element and projection type liquid crystal display apparatus | |
| KR20170079355A (en) | Light emitting apparatus, optical module including the apparatus, and vehicle including the module | |
| CN114252420A (en) | Sequencer fluorescence light splitting system and method | |
| CN1732472A (en) | Controllable two layer birefringent optical component | |
| CN109031866B (en) | Laser animation display method | |
| CN1945380A (en) | Illumination optical system and image projection apparatus | |
| CN1707229A (en) | Wavefront-measuring interferometer apparatus, and light beam measurement apparatus and method thereof | |
| CN205450433U (en) | Big object distance microscopic system multi -angle illumination device | |
| CN1304818C (en) | Depth of parallelism measuring method | |
| CN1066602C (en) | Optical projecting device and focus adjusting method of same | |
| CN102818204A (en) | Automotive lamp | |
| CN1256759A (en) | Method and apparatus for reducing coherence of light, method and apparatus for illumination, and fiber bundle | |
| CN210465981U (en) | Laser projection light path structure |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20060906 Termination date: 20140430 |