CN109470173B - Double-channel simultaneous phase shift interference microscope system - Google Patents

Double-channel simultaneous phase shift interference microscope system Download PDF

Info

Publication number
CN109470173B
CN109470173B CN201811635318.1A CN201811635318A CN109470173B CN 109470173 B CN109470173 B CN 109470173B CN 201811635318 A CN201811635318 A CN 201811635318A CN 109470173 B CN109470173 B CN 109470173B
Authority
CN
China
Prior art keywords
light
unit
measuring
beams
phase shift
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.)
Active
Application number
CN201811635318.1A
Other languages
Chinese (zh)
Other versions
CN109470173A (en
Inventor
吕晓旭
孙振达
钟丽云
王翰林
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
South China Normal University
Original Assignee
South China Normal University
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by South China Normal University filed Critical South China Normal University
Priority to CN201811635318.1A priority Critical patent/CN109470173B/en
Publication of CN109470173A publication Critical patent/CN109470173A/en
Application granted granted Critical
Publication of CN109470173B publication Critical patent/CN109470173B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01BMEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B11/00Measuring arrangements characterised by the use of optical techniques
    • G01B11/24Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
    • G01B11/2441Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures using interferometry
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01BMEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B11/00Measuring arrangements characterised by the use of optical techniques
    • G01B11/24Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
    • G01B11/25Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures by projecting a pattern, e.g. one or more lines, moiré fringes on the object
    • G01B11/254Projection of a pattern, viewing through a pattern, e.g. moiré
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01BMEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B9/00Measuring instruments characterised by the use of optical techniques
    • G01B9/02Interferometers
    • G01B9/02001Interferometers characterised by controlling or generating intrinsic radiation properties

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Computer Vision & Pattern Recognition (AREA)
  • Instruments For Measurement Of Length By Optical Means (AREA)
  • Investigating Or Analysing Materials By Optical Means (AREA)

Abstract

The invention discloses a double-channel simultaneous phase shift interference microscope system, which relates to the field of optical interference and comprises a light splitting unit, a reference light path unit, a measuring light path unit, a beam combining unit and an image acquisition unit; the light splitting unit is used for splitting incident light waves into measuring beams and reference beams, wherein the transmission directions of the measuring beams and the reference beams are mutually vertical, and the polarization planes of the measuring beams and the reference beams are mutually orthogonal; the reference light path unit is used for transmitting the reference light beam and performing spatial phase shift on the reference light beam; the measuring light path unit is used for transmitting the measuring light beam, performing space domain phase shift on the measuring light beam, and generating an object light beam after the measuring light beam passes through an object to be measured; the beam combination unit is used for combining the reference beam and the object beam after the space phase shift; the image acquisition unit is used for splitting the beam and acquiring two phase-shift interference fringe patterns on two channels; the method has the advantages of reducing cost and technical difficulty, and correcting the measurement system by the time domain phase shift function on the basis of the simultaneous space domain phase shift function.

Description

Double-channel simultaneous phase shift interference microscope system
Technical Field
The invention relates to an optical interference microscope system, in particular to a dual-channel simultaneous phase shift interference microscope system.
Background
In recent decades, with the development of photoelectric image sensing technology, computer technology and image processing technology, optical phase measurement microscopy has also made great progress; the optical phase measurement microscopy has the advantages of full field, rapidness, high precision, non-contact and no damage, one or more interferograms with monotonous phase shift are collected by a photoelectric image sensor (such as a CCD (charge coupled device) and a CMOS (complementary metal oxide semiconductor)) and the phase distribution of a sample can be calculated by utilizing a phase demodulation algorithm, meanwhile, the high-precision measurement of the three-dimensional shape information of the sample is realized, and the measurement precision can reach 1/100 wavelength; has wide application in cell biology, biological tissue, organ, clinical detection and diagnosis, optical surface detection and other aspects.
Compared with other interference measurement technologies, the phase-shift interference measurement technology has the advantages of thorough background noise elimination, high measurement precision and the like, but also has the problem that a plurality of phase-shift interferograms need to be acquired by using a phase-shift device at different moments, so that the measurement result is easily influenced by external vibration and air crosstalk, and dynamic phase measurement cannot be realized. The method is characterized in that a polarized optical element is used for phase shifting orthogonal polarized light, three or four interference patterns with phase shift difference pi/2 are simultaneously formed on the target surface of a photosensitive chip of one or more cameras, and then a three-step or four-step phase shift algorithm is used for calculating the phase. There are three main ways to achieve: firstly, forming interferograms with different phase shift quantities on target surfaces of photosensitive chips of a plurality of cameras by utilizing a beam splitter prism and a polarizing device; secondly, different areas on the target surface of a photosensitive chip are simultaneously acquired with interference patterns with different phase shift quantities by using a grating or other light splitting elements and polarizing devices; and thirdly, by utilizing a polarization phase shift array device, taking four pixels as a unit on the target surface of a photosensitive chip of one camera, enabling the pixels at different positions to have a specific phase shift period, forming a phase shift interference pattern by an acquired image in a separation and interpolation mode, and obtaining phase distribution through a phase shift phase recovery algorithm to realize dynamic phase measurement.
The above methods can realize the dynamic phase measurement of spatial domain simultaneous phase shift, but have the following problems:
firstly, a plurality of image sensor systems need to ensure that a plurality of cameras synchronously acquire images, and the measurement results are greatly influenced by the inconsistent photoelectric properties and different spatial relative positions of a plurality of CCDs;
secondly, the simultaneous acquisition of a plurality of phase-shift interferograms in different areas of a single CCD target surface is limited by various conditions, for example, the diffraction direction of a grating is influenced by the wavelength, so that the method can only be applied to single-wavelength measurement but cannot be used for measuring white light or narrow-band light, the spatial resolution is insufficient, a special image sensor is required, and the like;
thirdly, the pixel mask element is expensive to manufacture, and thus, the wide commercial application is difficult to realize.
Disclosure of Invention
The invention provides a double-channel simultaneous phase shift interference microscope system aiming at the problems in the background technology, which reduces the cost and the technical difficulty, has the time domain phase shift function on the basis of having the space domain simultaneous phase shift function, can realize the time domain phase shift phase measurement, and can also correct the measurement system.
In order to achieve the above object, the present invention provides a dual-channel simultaneous phase-shifting interference microscopy system, at least comprising: the device comprises a light splitting unit, a reference light path unit, a measuring light path unit, a beam combining unit and an image acquisition unit; wherein,
the light splitting unit is used for splitting incident light waves into measuring beams and reference beams, wherein the transmission directions of the measuring beams and the reference beams are mutually vertical, and the polarization planes of the measuring beams and the reference beams are mutually orthogonal;
the reference light path unit is used for transmitting the reference light beam and performing spatial phase shift on the reference light beam;
the measuring light path unit is used for transmitting the measuring light beam, performing space domain phase shift on the measuring light beam, and generating an object light beam after the measuring light beam passes through an object to be measured;
the beam combination unit is used for combining the reference beam and the object beam after the space phase shift;
and the image acquisition unit is used for splitting the combined light beam and acquiring two phase-shift interference fringe patterns on two channels.
Preferably, the system further comprises: and the light source unit is used for generating plane light waves with uniform light intensity distribution and transmitting the plane light waves to the light splitting unit.
Preferably, the light source unit includes: the device comprises a light source generator, a polarization attenuator and a light beam expanding and collimating assembly, wherein the light source generator generates linearly polarized light waves, the linearly polarized light waves are attenuated by the polarization attenuator and the polarization direction of the light waves is rotated, and planar light waves with uniform light intensity distribution are formed by the linearly polarized light waves through the beam expanding and collimating assembly.
Preferably, the reference light path unit may be sequentially configured to: the reference beam forms a reference beam of circularly polarized light after being reflected by the first 1/4 wave plate and the first reflector;
the measuring light path unit is arranged as follows: the device comprises a first 1/2 wave plate, a second reflector and an imaging objective lens, wherein an object to be measured is arranged at the front end of the imaging objective lens, measuring light beams form linearly polarized light with a certain included angle with the horizontal direction through the first 1/2 wave plate, the linearly polarized light irradiates the surface of the object to be measured through the second reflector, and object light waves are formed through the imaging objective lens after the linearly polarized light transmits through the object to be measured.
Preferably, the reference optical path unit may be further configured to, in sequence: the reference light beam forms a circularly polarized reference light beam after being reflected by the second 1/2 wave plate, the first 1/4 wave plate and the first reflector;
the measuring light path unit is arranged as follows: the device comprises a first 1/2 wave plate, a second reflector and an imaging objective lens, wherein an object to be measured is arranged at the front end of the imaging objective lens, measuring light beams form linearly polarized light with a certain included angle with the horizontal direction through the first 1/2 wave plate, the linearly polarized light irradiates the surface of the object to be measured through the second reflector, and object light waves are formed through the imaging objective lens after the linearly polarized light transmits through the object to be measured.
Preferably, the reference optical path unit may be further configured to, in sequence: the device comprises a first 1/4 wave plate, a second 1/2 wave plate and a first reflector, wherein a reference beam forms a reference beam of circularly polarized light after being reflected by the first 1/4 wave plate, the second 1/2 wave plate and the first reflector;
the measuring light path unit is arranged as follows: the device comprises a first 1/2 wave plate, a second reflector and an imaging objective lens, wherein an object to be measured is arranged at the front end of the imaging objective lens, measuring light beams form linearly polarized light with a certain included angle with the horizontal direction through the first 1/2 wave plate, the linearly polarized light irradiates the surface of the object to be measured through the second reflector, and object light waves are formed through the imaging objective lens after the linearly polarized light transmits through the object to be measured.
Preferably, the image acquisition unit includes: the combined light beam is split by the polarization beam splitter prism to obtain two paths of light beams which are perpendicular to each other, and two phase-shift interference fringe patterns are acquired and obtained on two channels of the first photoelectric image sensor and the second photoelectric image sensor.
Preferably, the mirror is replaced by a piezoelectric ceramic to temporally phase shift the reference beam.
Preferably, said certain angle is 45 °.
Preferably, after the combined light beam is split by the polarization splitting prism to obtain two paths of light beams perpendicular to each other, the size of the light beam is matched with the sizes of the photosensitive surfaces of the first photoelectric image sensor and the first photoelectric image sensor.
The invention provides a double-channel simultaneous phase shift interference microscope system, which has the following beneficial effects:
(1) the invention is a space-time mixed phase-shifting double-channel interference microscope system, combines a two-step phase-shifting algorithm, can realize static and dynamic phase measurement, and greatly reduces the cost and the technical difficulty compared with other airspace phase-shifting technologies;
(2) the interference microscope system disclosed by the patent of the invention has the time domain phase shift function on the basis of having the space domain simultaneous phase shift function, can realize time domain phase shift phase measurement (the reflector is changed into PZT on a reference light path), and can also correct the measurement system;
(3) compared with other systems, the invention is simpler, has lower difficulty in matching the space positions of the two CCDs, and has higher light energy utilization rate of the system.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.
FIG. 1 is a block diagram of a two-channel simultaneous phase-shifting interference microscopy system according to a first preferred embodiment of the present invention;
FIG. 2 is a block diagram of a light source unit according to a first preferred embodiment of the present invention;
FIG. 3 is a block diagram of a reference optical path unit according to a first preferred embodiment of the present invention;
FIG. 4 is a block diagram of a measuring optical path unit according to a first preferred embodiment of the present invention;
FIG. 5 is a block diagram of an image capturing unit according to a first preferred embodiment of the present invention;
FIG. 6 is a block diagram of the overall detailed structure of a dual-channel simultaneous phase-shifting interference microscopy system according to a first preferred embodiment of the present invention;
FIG. 7 is a block diagram of a reference optical path unit according to a second preferred embodiment of the present invention;
FIG. 8 is a block diagram of a reference optical path unit according to a third preferred embodiment of the present invention;
description of the symbols:
1-a light source unit; 2-a light splitting unit; 3-a reference light path unit; 4-a measurement light path unit; 5-a beam combining unit; 6-an image acquisition unit; 101-a light source generator; 102-a polarization attenuator; 103-a beam expanding and collimating assembly; 301-a first 1/4 waveplate; 302-a first mirror; 303-second 1/2 wave plate; 401-a first 1/2 waveplate; 402-a second mirror; 403-an imaging objective lens; 601-a polarization beam splitter prism; 602-a first monochrome black and white image sensor; 603-a second monochrome black and white image sensor;
the implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
It should be noted that, if directional indications (such as up, down, left, right, front, and back … …) are involved in the embodiment of the present invention, the directional indications are only used to explain the relative positional relationship between the components, the movement situation, and the like in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indications are changed accordingly.
In addition, if there is a description of "first", "second", etc. in an embodiment of the present invention, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.
The invention provides a double-channel simultaneous phase shift interference microscope system;
in a first preferred embodiment of the present invention, as shown in fig. 1, the present invention comprises: the device comprises a light source unit 1, a light splitting unit 2, a reference light path unit 3, a measurement light path unit 4, a beam combining unit 5 and an image acquisition unit 6; the light source unit 1 is used for generating a planar light wave with uniform light intensity distribution and transmitting the planar light wave to the light splitting unit 2; the light splitting unit 2 is used for splitting incident light waves into measuring beams and reference beams, wherein the transmission directions of the measuring beams and the reference beams are mutually vertical, and the polarization planes of the measuring beams and the reference beams are mutually orthogonal; the reference light path unit 3 is used for transmitting the reference light beam and performing spatial phase shift on the reference light beam; the measuring light path unit 4 is used for transmitting the measuring light beam, performing space domain phase shift on the measuring light beam, and generating an object light beam after the measuring light beam passes through an object to be measured; the beam combination unit 5 is used for combining the reference beam and the object beam after the spatial phase shift; the image acquisition unit 6 is used for splitting the combined light beam and acquiring two interferograms with the phase shift amount pi/2 on two channels.
In the embodiment of the present invention, as shown in fig. 2, the light source unit 1 includes: the interferometer comprises a light source generator 101 (a laser), a polarization attenuator 102 and a beam expanding collimation assembly 103, wherein the light source generator 101 generates linear polarization laser light waves, namely, measurement light waves of the interferometer are provided, the polarization attenuator 102 can be used for adjusting the total light intensity of the measurement light waves and the light intensity ratio of reference light and the measurement light, the linear polarization light waves are attenuated by the polarization attenuator 102 and the polarization direction of the rotation light waves, and planar light waves with uniform light intensity distribution are formed after passing through the beam expanding collimation assembly 103;
in the embodiment of the invention, the light splitting unit 2 adopts a first polarization light splitting prism to split an incident light beam into a measuring light beam and a reference light beam, wherein the transmission directions of the measuring light beam and the reference light beam are mutually vertical, the polarization planes of the measuring light beam and the reference light beam are mutually orthogonal, the light beam in the vertical incidence direction is used as the reference light beam, namely, the polarization component in the x direction is transmitted to the reference plane direction, and the light beam in the horizontal incidence direction (the polarization component in the y direction;
in the embodiment of the present invention, the spatial coordinate system in the light beam transmission process is defined as: the direction of the light beam transmitted along the optical axis of the system is the z direction, the x direction is vertical to the incident surface and the z direction, the y direction is parallel to the incident surface and vertical to the z direction, and the three directions of x, y and z form a right-hand coordinate system;
in the embodiment of the present invention, as shown in fig. 3, the reference optical path unit 3 is sequentially configured as follows: the device comprises a first 1/4 wave plate 301 and a first reflector 302, wherein an included angle between the fast axis direction of the first 1/4 wave plate and the horizontal direction is 45 degrees, a reference beam passes through the first 1/4 wave plate 301, so that P light becomes a circularly polarized light beam, and the circularly polarized light beam is reflected by the first reflector 302 to form a circularly polarized reference beam;
in the embodiment of the present invention, the first mirror 302 may be replaced by piezoelectric ceramics (PZT) as a phase shift device of the time domain phase shift unit, so as to implement the time domain phase shift function of the system.
In the embodiment of the present invention, as shown in fig. 4, the measurement optical path unit 4 is configured to: the measuring device comprises a first 1/2 wave plate 401, a second reflecting mirror 402 and an imaging objective lens 403, wherein an included angle between the fast axis direction of the first 1/2 wave plate 401 and the horizontal direction is 22.5 degrees, an object to be measured (a test object is placed and fixed through an object stage) is arranged at the front end of the imaging objective lens 403, measuring light beams pass through the first 1/2 wave plate 401 to enable S light to be changed into a linearly polarized light beam with an included angle of 45 degrees with the horizontal direction, the linearly polarized light beam irradiates the surface of the object to be measured through the second reflecting mirror 402, and the linearly polarized light beam forms object light waves through the imaging objective lens 403; the imaging objective lens 403 is used for making the diffracted object light modulated and transmitted from the object to be measured 9 form a clear image on the image sensor;
in the embodiment of the invention, the beam combination unit 5 adopts a non-polarization beam splitting prism to enable the measuring beam and the reference beam to propagate in the same direction again;
in the embodiment of the present invention, as shown in fig. 5, the image capturing unit 6 includes: the combined light beam is split by the polarization beam splitter prism to obtain two paths of light beams which are perpendicular to each other, the size of the light beam is matched with the size of photosensitive surfaces of the first photoelectric image sensor 602 and the second photoelectric image sensor 603, so that P light and S light in the two paths of light respectively form interference light fields, and two phase-shift interference fringe patterns with the phase shift of 90 degrees can be simultaneously obtained on two channels through the respective acquisition and recording of the first photoelectric image sensor 602 and the second photoelectric image sensor 603.
In the embodiment of the invention, PZT is used as a phase shift device, two groups of interferograms can be collected in two channels at the same time, background phases of the two channels are respectively calculated by using an AIA algorithm, and the phase shift amount between the two channels is 1.5915 by subtracting;
in the embodiment of the invention, the derivation process of the system Jones matrix is as follows:
because the polarization attenuator has no influence on the final polarization state of the system, the laser penetrating through the polarization attenuator is set as follows:
Figure BDA0001929900840000061
wherein a and b are the components of the laser light in the horizontal and vertical directions, respectively;
in the embodiment of the invention, the jones matrix of the 1/2 wave plate is as follows:
Figure BDA0001929900840000062
wherein alpha is1Is the angle between the fast axis direction of 1/2 wave plate and the horizontal direction, in this embodiment, α1=22.5°;
In the embodiment of the invention, the jones matrix of the 1/4 wave plate is as follows:
Figure BDA0001929900840000063
wherein α is an included angle between the fast axis direction of the 1/4 wave plate and the horizontal direction, and α is 45 ° in this embodiment;
phase of the object is
Figure BDA0001929900840000064
Specular reflection
Figure BDA0001929900840000065
The transmitted light of the PBS is recorded as
Figure BDA0001929900840000066
The reflected light is recorded as
Figure BDA0001929900840000067
This process can be represented by the jones matrix:
the light transmitted through BS1 is:
Figure BDA0001929900840000068
Figure BDA0001929900840000071
the light obtained on the first photo-image sensor CCD after passing through PBS2 is:
Figure BDA0001929900840000072
Figure BDA0001929900840000073
similarly, the light obtained on the second photoelectric image sensor CCD is:
Figure BDA0001929900840000074
Figure BDA0001929900840000075
in summary, the overall schematic diagram of the system is shown in fig. 6, and the spatial coordinate system during the transmission of the light beam is defined as: the direction of the light beam transmitted along the optical axis of the system is the z direction, the x direction is vertical to the incident surface and the z direction, the y direction is parallel to the incident surface and vertical to the z direction, and the three directions of x, y and z form a right-hand coordinate system; the invention provides a dual-channel interference microscope system which is based on orthogonal polarized light modulation and has the functions of spatial domain simultaneous phase shift and time domain phase shift; the system is simple, feasible and easy to operate, and is suitable for various phase demodulation algorithms. The invention uses a polarization beam splitter prism to separate measurement light and reference light, uses a lateral reflecting surface as a reference surface, adds 1/4 wave plates into the reference light to form circularly polarized light, adds 1/2 wave plates into the test light to form linearly polarized light with an included angle of 45 degrees with the horizontal direction, and the linearly polarized light is combined by a non-polarization beam splitter prism and split by the polarization beam splitter prism, and finally two interference patterns with the phase shift amount of pi/2 are recorded by two photoelectric image sensors at the same time.
In a second preferred embodiment of the present invention, as shown in fig. 1, it comprises: the device comprises a light source unit 1, a light splitting unit 2, a reference light path unit 3, a measurement light path unit 4, a beam combining unit 5 and an image acquisition unit 6; the light source unit 1 is used for generating a planar light wave with uniform light intensity distribution and transmitting the planar light wave to the light splitting unit 2; the light splitting unit 2 is used for splitting incident light waves into measuring beams and reference beams, wherein the transmission directions of the measuring beams and the reference beams are mutually vertical, and the polarization planes of the measuring beams and the reference beams are mutually orthogonal; the reference light path unit 3 is used for transmitting the reference light beam and performing spatial phase shift on the reference light beam; the measuring light path unit 4 is used for transmitting the measuring light beam, performing space domain phase shift on the measuring light beam, and generating an object light beam after the measuring light beam passes through an object to be measured; the beam combination unit 5 is used for combining the reference beam and the object beam after the spatial phase shift; the image acquisition unit 6 is used for splitting the combined light beam and acquiring two interferograms with the phase shift amount pi/2 on two channels.
In the embodiment of the present invention, as shown in fig. 2, the light source unit 1 includes: the interferometer comprises a light source generator 101, a polarization attenuator 102 and a light beam expanding and collimating assembly 103, wherein the light source generator 101 generates linearly polarized light waves, namely, measurement light waves of the interferometer are provided, the polarization attenuator 102 can be used for adjusting the total light intensity of the test light waves and the light intensity ratio of reference light to test light, the linearly polarized light waves are attenuated by the polarization attenuator 102 and the polarization direction of the light waves is rotated, and planar light waves with uniform light intensity distribution are formed after passing through the beam expanding and collimating assembly 103;
in the embodiment of the invention, the light splitting unit 2 adopts a first polarization light splitting prism to split an incident light beam into a measuring light beam and a reference light beam, wherein the transmission directions of the measuring light beam and the reference light beam are mutually vertical, the polarization planes of the measuring light beam and the reference light beam are mutually orthogonal, the light beam in the vertical incidence direction is used as the reference light beam, namely, the polarization component in the x direction is transmitted to the reference plane direction, and the light beam in the horizontal incidence direction (the polarization component in the y direction;
in the embodiment of the present invention, the spatial coordinate system in the light beam transmission process is defined as: the direction of the light beam transmitted along the optical axis of the system is the z direction, the x direction is vertical to the incident surface and the z direction, the y direction is parallel to the incident surface and vertical to the z direction, and the three directions of x, y and z form a right-hand coordinate system.
In the embodiment of the present invention, as shown in fig. 7, the reference optical path unit 3 may further be sequentially configured as follows: the second 1/2 wave plate 303, the first 1/4 wave plate 301 and the first reflector 302, the second 1/2 wave plate 303 has an included angle of 22.5 degrees between the fast axis direction and the horizontal direction, and the first 1/4 wave plate 301 has an included angle of 0 degree or 90 degrees between the fast axis direction and the horizontal direction; the reference beam passes through the second 1/2 wave plate 303 and the first 1/4 wave plate 301, so that the P light becomes a circularly polarized light, and the circularly polarized light reference beam is formed after the P light is reflected by the first reflecting mirror 302;
in the embodiment of the present invention, the first mirror 302 may be replaced by piezoelectric ceramics (PZT) as a phase shift device of the time domain phase shift unit, so as to implement the time domain phase shift function of the system.
In the embodiment of the present invention, as shown in fig. 4, the measurement optical path unit 4 is configured to: the measuring device comprises a first 1/2 wave plate 401, a second reflector 402 and an imaging objective lens 403, wherein an included angle between the fast axis direction of the first 1/2 wave plate 401 and the horizontal direction is 22.5 degrees, an object to be measured is arranged at the front end of the imaging objective lens 403, measuring light beams pass through the first 1/2 wave plate 401 to enable S light to become a linear polarized light beam with an included angle of 45 degrees with the horizontal direction, the linear polarized light beam irradiates the surface of the object to be measured through the second reflector 402, and the linear polarized light beam forms object light waves through the imaging objective lens 403 after transmitting the object to be; the imaging objective lens 403 is used for making the diffracted object light modulated and transmitted from the object to be measured 9 form a clear image on the image sensor;
in the embodiment of the present invention, the beam combining unit 5 combines the light beams by using a non-polarization beam splitting prism;
in an embodiment of the present invention, the image capturing unit 6 includes: the combined light beam is split by the polarization beam splitter prism to obtain two paths of light beams which are perpendicular to each other, the size of the light beam is matched with the size of photosensitive surfaces of the first photoelectric image sensor 602 and the second photoelectric image sensor 603, so that P light and S light in the two paths of light respectively form interference light fields, and two phase-shift interference fringe patterns with the phase shift of 90 degrees can be simultaneously obtained on two channels through the respective acquisition and recording of the first photoelectric image sensor 602 and the second photoelectric image sensor 603.
In the embodiment of the present invention, the derivation process of the calculation of the light wave has been described in the first preferred embodiment, and will not be repeated here;
in a third preferred embodiment of the present invention, as shown in fig. 1, comprises: the device comprises a light source unit 1, a light splitting unit 2, a reference light path unit 3, a measurement light path unit 4, a beam combining unit 5 and an image acquisition unit 6; the light source unit 1 is used for generating a planar light wave with uniform light intensity distribution and transmitting the planar light wave to the light splitting unit 2; the light splitting unit 2 is used for splitting incident light waves into measuring beams and reference beams, wherein the transmission directions of the measuring beams and the reference beams are mutually vertical, and the polarization planes of the measuring beams and the reference beams are mutually orthogonal; the reference light path unit 3 is used for transmitting the reference light beam and performing spatial phase shift on the reference light beam; the measuring light path unit 4 is used for transmitting the measuring light beam, performing space domain phase shift on the measuring light beam, and generating an object light beam after the measuring light beam passes through an object to be measured; the beam combination unit 5 is used for combining the reference beam and the object beam after the spatial phase shift; the image acquisition unit 6 is used for splitting the combined light beam and acquiring two interferograms with the phase shift amount pi/2 on two channels.
In the embodiment of the present invention, as shown in fig. 2, the light source unit 1 includes: the interferometer comprises a light source generator 101, a polarization attenuator 102 and a light beam expanding and collimating assembly 103, wherein the light source generator 101 generates linearly polarized light waves, namely, measurement light waves of the interferometer are provided, the polarization attenuator 102 can be used for adjusting the total light intensity of the test light waves and the light intensity ratio of reference light to test light, the linearly polarized light waves are attenuated by the polarization attenuator 102 and the polarization direction of the light waves is rotated, and planar light waves with uniform light intensity distribution are formed after passing through the beam expanding and collimating assembly 103;
in the embodiment of the invention, the light splitting unit 2 adopts a first polarization light splitting prism to split an incident light beam into a measuring light beam and a reference light beam, wherein the transmission directions of the measuring light beam and the reference light beam are mutually vertical, the polarization planes of the measuring light beam and the reference light beam are mutually orthogonal, the light beam in the vertical incidence direction is used as the reference light beam, namely, the polarization component in the x direction is transmitted to the reference plane direction, and the light beam in the horizontal incidence direction (the polarization component in the y direction;
in the embodiment of the present invention, the spatial coordinate system in the light beam transmission process is defined as: the direction of the light beam transmitted along the optical axis of the system is the z direction, the x direction is vertical to the incident surface and the z direction, the y direction is parallel to the incident surface and vertical to the z direction, and the three directions of x, y and z form a right-hand coordinate system.
In the embodiment of the present invention, as shown in fig. 8, the reference optical path unit 3 may further be sequentially configured as follows: the device comprises a first 1/4 wave plate 301, a second 1/2 wave plate 303 and a first reflector 302, wherein an included angle between the fast axis direction of the first 1/4 wave plate 301 and the horizontal direction is 45 degrees, an included angle between the fast axis direction of the second 1/2 wave plate 303 and the horizontal direction is 45 degrees, a reference light beam passes through the first 1/4 wave plate 301 and the second 1/2 wave plate 303, so that the P light becomes a circularly polarized light beam, and the circularly polarized light beam is formed after being reflected by the first reflector 302;
in the embodiment of the present invention, the first mirror 302 may be replaced by piezoelectric ceramics (PZT) as a phase shift device of the time domain phase shift unit, so as to implement the time domain phase shift function of the system.
In the embodiment of the present invention, as shown in fig. 4, the measurement optical path unit 4 is configured to: the measuring device comprises a first 1/2 wave plate 401, a second reflector 402 and an imaging objective lens 403, wherein an included angle between the fast axis direction of the first 1/2 wave plate 401 and the horizontal direction is 22.5 degrees, an object to be measured is arranged at the front end of the imaging objective lens 403, measuring light beams pass through the first 1/2 wave plate 401 to enable S light to become a linear polarized light beam with an included angle of 45 degrees with the horizontal direction, the linear polarized light beam irradiates the surface of the object to be measured through the second reflector 402, and the linear polarized light beam forms object light waves through the imaging objective lens 403 after transmitting the object to be; the imaging objective lens 403 is used for making the diffracted object light modulated and transmitted from the object to be measured 9 form a clear image on the image sensor;
in the embodiment of the present invention, the beam combining unit 5 combines the light beams by using a non-polarization beam splitting prism;
in an embodiment of the present invention, the image capturing unit 6 includes: the combined light beam is split by the polarization beam splitter prism to obtain two paths of light beams which are perpendicular to each other, the size of the light beam is matched with the size of photosensitive surfaces of the first photoelectric image sensor 602 and the second photoelectric image sensor 603, so that P light and S light in the two paths of light respectively form interference light fields, and two phase-shift interference fringe patterns with the phase shift of 90 degrees can be simultaneously obtained on two channels through the respective acquisition and recording of the first photoelectric image sensor 602 and the second photoelectric image sensor 603.
In the embodiment of the present invention, the derivation process of the calculation of the light wave has been described in the first preferred embodiment, and will not be repeated here;
the above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention, and all modifications and equivalents of the present invention, which are made by the contents of the present specification and the accompanying drawings, or directly/indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims (10)

1. A dual channel simultaneous phase-shifting interference microscopy system, comprising at least: the device comprises a light splitting unit, a reference light path unit, a measuring light path unit, a beam combining unit and an image acquisition unit; wherein,
the light splitting unit is used for splitting incident light waves into measuring beams and reference beams, wherein the transmission directions of the measuring beams and the reference beams are mutually vertical, and the polarization planes of the measuring beams and the reference beams are mutually orthogonal;
the reference light path unit is used for transmitting the reference light beam and performing spatial phase shift on the reference light beam;
the measuring light path unit is used for transmitting the measuring light beam, performing space domain phase shift on the measuring light beam, and generating an object light beam after the measuring light beam passes through an object to be measured;
the beam combination unit is used for combining the reference beam and the object beam after the space phase shift;
the image acquisition unit is used for splitting the beam and acquiring two phase-shift interference fringe patterns on two channels;
the measuring light path unit is arranged as follows: the device comprises a first 1/2 wave plate, a second reflector and an imaging objective lens, wherein an object to be measured is arranged at the front end of the imaging objective lens, measuring light beams form linearly polarized light with a certain included angle with the horizontal direction through the first 1/2 wave plate, the linearly polarized light irradiates the surface of the object to be measured through the second reflector, and object light waves are formed through the imaging objective lens after the linearly polarized light transmits through the object to be measured.
2. The dual channel simultaneous phase shifting interference microscopy system of claim 1, further comprising: and the light source unit is used for generating plane light waves with uniform light intensity distribution and transmitting the plane light waves to the light splitting unit.
3. The dual-channel simultaneous phase-shifting interference microscopy system as claimed in claim 2, wherein the light source unit comprises: a light source generator, a polarization attenuator and a beam expanding and collimating assembly, wherein,
the light source generator generates linearly polarized light waves, the linearly polarized light waves are attenuated by the polarization attenuator and the polarization direction of the light waves is rotated, and planar light waves with uniform light intensity distribution are formed after the linearly polarized light waves pass through the beam expanding collimation assembly.
4. The dual-channel simultaneous phase-shifting interference microscopy system of claim 1,
the reference light path unit can be sequentially arranged as follows: the reference beam forms a reference beam of circularly polarized light after being reflected by the first 1/4 wave plate and the first reflector.
5. The dual-channel simultaneous phase-shifting interference microscopy system of claim 1,
the reference light path unit can be further sequentially set as follows: the reference beam forms a circularly polarized reference beam after being reflected by the second 1/2 wave plate, the first 1/4 wave plate and the first reflector.
6. The dual-channel simultaneous phase-shifting interference microscopy system of claim 1,
the reference light path unit can be further sequentially set as follows: the device comprises a first 1/4 wave plate, a second 1/2 wave plate and a first reflector, wherein a reference beam forms a reference beam of circularly polarized light after being reflected by the first 1/4 wave plate, the second 1/2 wave plate and the first reflector.
7. The dual channel simultaneous phase shifting interference microscopy system of claim 1, wherein the image acquisition unit comprises: the combined light beam is split by the polarization beam splitter prism to obtain two paths of light beams which are perpendicular to each other, and two phase-shift interference fringe patterns are acquired and obtained on two channels of the first photoelectric image sensor and the second photoelectric image sensor.
8. The dual channel simultaneous phase-shifting interference microscopy system as claimed in claim 4 or claim 5 or claim 6 wherein the mirror is replaced with a piezo-ceramic to temporally phase shift the reference beam.
9. The dual channel simultaneous phase shifting interference microscopy system as claimed in claim 1 wherein the certain angle is 45 °.
10. The dual-channel simultaneous phase-shifting interference microscope system as claimed in claim 7, wherein the combined beam is split by the polarization splitting prism to obtain two beams perpendicular to each other, and the size of the beam is matched with the size of the photosensitive surfaces of the first photoelectric image sensor and the first photoelectric image sensor.
CN201811635318.1A 2018-12-29 2018-12-29 Double-channel simultaneous phase shift interference microscope system Active CN109470173B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201811635318.1A CN109470173B (en) 2018-12-29 2018-12-29 Double-channel simultaneous phase shift interference microscope system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201811635318.1A CN109470173B (en) 2018-12-29 2018-12-29 Double-channel simultaneous phase shift interference microscope system

Publications (2)

Publication Number Publication Date
CN109470173A CN109470173A (en) 2019-03-15
CN109470173B true CN109470173B (en) 2021-01-26

Family

ID=65676974

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201811635318.1A Active CN109470173B (en) 2018-12-29 2018-12-29 Double-channel simultaneous phase shift interference microscope system

Country Status (1)

Country Link
CN (1) CN109470173B (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110017793B (en) * 2019-04-10 2020-09-18 南京理工大学 Double-channel anti-vibration interference measurement device and method
CN111474140A (en) * 2020-03-23 2020-07-31 江苏大学 Double-channel orthogonal phase microscopic imaging sampling system
CN114200723A (en) * 2021-10-29 2022-03-18 华南师范大学 Liquid crystal variable phase delay device without transverse deviation of light beam
CN114397092B (en) * 2022-01-14 2024-01-30 深圳迈塔兰斯科技有限公司 Method and system for measuring super-surface phase
CN114459342B (en) * 2022-01-25 2023-07-04 华南师范大学 On-axis and off-axis digital holographic switching device based on parallel beam splitting prism

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7221760B2 (en) * 2001-03-30 2007-05-22 The University Of Connecticut Information security using digital holography
CN102520602A (en) * 2011-11-08 2012-06-27 浙江师范大学 Two-step quadrature phase-shift interferometry-based optical image encryption device and method
CN102914258A (en) * 2012-09-29 2013-02-06 哈尔滨工程大学 Synchronous phase shifting interference microscopy detection device and detection method based on orthogonal double-grating
CN102914257A (en) * 2012-09-29 2013-02-06 哈尔滨工程大学 Light-splitting synchronous phase shifting interference microscopy device and detection method
CN204854620U (en) * 2015-04-25 2015-12-09 林燕彬 With relevant measurement system that wades of shifting in steps
CN105404129B (en) * 2015-12-18 2017-12-05 南开大学 The method that any phase shift of three steps based on inner product algorithm eliminates digital hologram zero-order image
CN107462149B (en) * 2017-07-03 2020-08-11 华南师范大学 Phase-shift interferometry system and wave plate phase-shift method thereof
CN108267082B (en) * 2017-12-26 2020-07-14 华南师范大学 Method and system for simultaneous spatial domain and time domain polarization phase shift interference of two channels

Also Published As

Publication number Publication date
CN109470173A (en) 2019-03-15

Similar Documents

Publication Publication Date Title
CN109470173B (en) Double-channel simultaneous phase shift interference microscope system
US7230717B2 (en) Pixelated phase-mask interferometer
CA2805443C (en) Method and apparatus for imaging
US20070211256A1 (en) Linear-carrier phase-mask interferometer
CN107942523B (en) Phase recovery system based on light intensity transmission measurement calculation
CN110873957A (en) EPI illumination Fourier ptychographic imaging for thick samples
EP3118571B1 (en) Instantaneous phase-shift interferometer and measurement method
KR20100134609A (en) Apparatus and method for measuring surface topography of an object
JP2930406B2 (en) Method and apparatus for observing a moiré pattern on a surface to be tested by applying a moiré method utilizing phase shift
JP7233536B2 (en) Method, interferometer and signal processor for measuring input phase and/or input amplitude, respectively, of an input optical field
CN108957910B (en) Device and method for inspecting the surface of an object
KR102604960B1 (en) Method and system of holographic interferometry
CN105300273B (en) Dynamic Point Diffraction Interferometer with Adjustable Fringe Contrast
JPWO2003074967A1 (en) Polarization direction detection type two-dimensional light reception timing detection device and surface shape measurement device using the same
JPH0272336A (en) Optical correlation processor
KR100916593B1 (en) A 3D Shape Measuring System in Real Time
CN107144351B (en) A kind of broadband full polarization imaging method based on Mach Zehnder interferometer
CN114459620A (en) Device and method for generating pi phase shift between double interference channels through single wave plate
KR102007004B1 (en) Apparatus for measuring three dimensional shape
CN107421641B (en) A kind of broadband full polarization imaging device based on Mach Zehnder interferometer
CN108827176A (en) A kind of polarization four-step phase-shifting method for digital speckle interference technology
CA2955391A1 (en) Method and apparatus for measuring optical systems and surfaces with optical ray metrology
CN107923735A (en) Method and apparatus for the pattern for deriving body surface
JP2020153992A (en) Shape measurement device by white interferometer
JP2017026494A (en) Device for measuring shape using white interferometer

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant