CN113946116A - Three-dimensional displacement compact measuring device, method and medium for scattered light field holographic range - Google Patents
Three-dimensional displacement compact measuring device, method and medium for scattered light field holographic range Download PDFInfo
- Publication number
- CN113946116A CN113946116A CN202111276683.XA CN202111276683A CN113946116A CN 113946116 A CN113946116 A CN 113946116A CN 202111276683 A CN202111276683 A CN 202111276683A CN 113946116 A CN113946116 A CN 113946116A
- Authority
- CN
- China
- Prior art keywords
- displacement
- laser
- spectroscope
- light field
- light
- 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.)
- Pending
Links
- 238000006073 displacement reaction Methods 0.000 title claims abstract description 130
- 238000000034 method Methods 0.000 title claims abstract description 55
- 238000005259 measurement Methods 0.000 claims abstract description 53
- 230000003287 optical effect Effects 0.000 claims abstract description 34
- 238000003384 imaging method Methods 0.000 claims description 24
- 230000007935 neutral effect Effects 0.000 claims description 14
- 238000010586 diagram Methods 0.000 claims description 9
- 238000000691 measurement method Methods 0.000 claims description 9
- 238000010587 phase diagram Methods 0.000 claims description 5
- 238000012545 processing Methods 0.000 claims description 5
- 230000015572 biosynthetic process Effects 0.000 claims description 4
- 230000001678 irradiating effect Effects 0.000 claims description 4
- 238000003786 synthesis reaction Methods 0.000 claims description 4
- 238000004364 calculation method Methods 0.000 claims description 3
- 238000004590 computer program Methods 0.000 claims description 3
- 238000003860 storage Methods 0.000 claims description 3
- 238000005516 engineering process Methods 0.000 abstract description 19
- 230000001360 synchronised effect Effects 0.000 abstract description 6
- 230000010354 integration Effects 0.000 abstract description 3
- 230000009977 dual effect Effects 0.000 abstract description 2
- 230000010287 polarization Effects 0.000 description 19
- 238000001093 holography Methods 0.000 description 10
- 230000010363 phase shift Effects 0.000 description 6
- 238000012876 topography Methods 0.000 description 6
- 230000008569 process Effects 0.000 description 4
- 230000005540 biological transmission Effects 0.000 description 3
- 238000013461 design Methods 0.000 description 3
- 238000001514 detection method Methods 0.000 description 3
- 238000009826 distribution Methods 0.000 description 3
- 238000001914 filtration Methods 0.000 description 3
- 230000003321 amplification Effects 0.000 description 2
- 230000002238 attenuated effect Effects 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 230000004927 fusion Effects 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000003199 nucleic acid amplification method Methods 0.000 description 2
- 238000012634 optical imaging Methods 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 238000005299 abrasion Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000001427 coherent effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 230000002452 interceptive effect Effects 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03H—HOLOGRAPHIC PROCESSES OR APPARATUS
- G03H1/00—Holographic processes or apparatus using light, infrared or ultraviolet waves for obtaining holograms or for obtaining an image from them; Details peculiar thereto
- G03H1/0005—Adaptation of holography to specific applications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/02—Measuring arrangements characterised by the use of optical techniques for measuring length, width or thickness
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
- G01B7/02—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring length, width or thickness
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03H—HOLOGRAPHIC PROCESSES OR APPARATUS
- G03H1/00—Holographic processes or apparatus using light, infrared or ultraviolet waves for obtaining holograms or for obtaining an image from them; Details peculiar thereto
- G03H1/02—Details of features involved during the holographic process; Replication of holograms without interference recording
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03H—HOLOGRAPHIC PROCESSES OR APPARATUS
- G03H1/00—Holographic processes or apparatus using light, infrared or ultraviolet waves for obtaining holograms or for obtaining an image from them; Details peculiar thereto
- G03H1/04—Processes or apparatus for producing holograms
- G03H1/0402—Recording geometries or arrangements
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03H—HOLOGRAPHIC PROCESSES OR APPARATUS
- G03H1/00—Holographic processes or apparatus using light, infrared or ultraviolet waves for obtaining holograms or for obtaining an image from them; Details peculiar thereto
- G03H1/0005—Adaptation of holography to specific applications
- G03H2001/0033—Adaptation of holography to specific applications in hologrammetry for measuring or analysing
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03H—HOLOGRAPHIC PROCESSES OR APPARATUS
- G03H1/00—Holographic processes or apparatus using light, infrared or ultraviolet waves for obtaining holograms or for obtaining an image from them; Details peculiar thereto
- G03H1/04—Processes or apparatus for producing holograms
- G03H1/0402—Recording geometries or arrangements
- G03H2001/0428—Image holography, i.e. an image of the object or holobject is recorded
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03H—HOLOGRAPHIC PROCESSES OR APPARATUS
- G03H1/00—Holographic processes or apparatus using light, infrared or ultraviolet waves for obtaining holograms or for obtaining an image from them; Details peculiar thereto
- G03H1/04—Processes or apparatus for producing holograms
- G03H1/0402—Recording geometries or arrangements
- G03H2001/0436—Holographic camera
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Length Measuring Devices By Optical Means (AREA)
Abstract
The invention provides a device, a method and a medium for compact measurement of three-dimensional displacement in a holographic range of a scattered light field, which comprise a first laser, a second laser, a first spectroscope, a second spectroscope, a convergent lens, a pinhole, a first plane mirror, a second plane mirror, a third spectroscope and a camera, and realize dynamic measurement of three-dimensional vector displacement of a high-scattering object by combining the technologies of holographic measurement of the scattered light field, digital image correlation and the like. The measuring device of the invention adopts dual wavelengths, realizes optical path multiplexing, has compact structure, is suitable for integration, is simple and practical, and has larger displacement measuring range compared with single wavelength. The invention integrates the digital image correlation technology and the scattered light field holographic measurement technology, has the advantages of non-contact property, high measurement precision, high measurement speed, large measurement range, synchronous measurement of three-dimensional vector displacement, compact device and the like, and has wide application prospect in high-precision measurement occasions such as aerospace, miniature medical robots and the like.
Description
Technical Field
The invention relates to the technical field of optical measurement, in particular to a device and a method for compact measurement of three-dimensional displacement in a holographic range of a scattered light field and a medium, and particularly relates to a device and a method for compact measurement of holographic large-range three-dimensional displacement of the scattered light field.
Background
With the rapid development of precision machining technology in the industries of mechanical manufacturing, semiconductor industry and the like, the corresponding technological requirements for various ultra-precision devices or optical elements are increasing day by day. For many occasions requiring precise matching of parts, such as aerospace, miniature medical robots and the like, how to obtain displacement or deformation of precise elements is a very critical problem.
In the existing measurement method, the traditional contact type displacement measurement method has low measurement speed, introduces artificial stress interference, and may cause abrasion to the surface of an object due to contact force, so that the traditional contact type displacement measurement method is not suitable for measurement of precise elements. In the non-contact measurement method, the digital holographic technology has the advantages of non-contact measurement, high precision of full-field measurement, and the like, and is a very ideal high-precision displacement detection means. Digital holography is generally used for the measurement of objects with specular surfaces and fails for objects with scattering surfaces. Meanwhile, a single digital holographic device is not suitable for measuring three-dimensional vector displacement. If synchronous three-dimensional vector displacement measurement is to be realized, three sets of digital holographic devices are often needed, and each set is responsible for measuring displacement of one dimension. However, the installation of three sets of digital holographic devices is complicated. Meanwhile, the utilization efficiency of information is not high, only the phase diagram is utilized, and the intensity diagrams of the three devices are totally discarded. Meanwhile, the measurement range of single-wavelength holography is limited, usually in the order of hundreds of nanometers, and the single-wavelength holography method fails in the occasions with higher requirements for the measurement range.
Patent document No. CN102967261A discloses a novel laser displacement measurement method based on a digital speckle correlation method, which specifically includes: laser is focused to vertically enter the surface of a moving measured object; receiving scattered light at an incident light point on the surface of a measured object, and imaging the scattered light on a sensitive surface of the CCD through an imaging lens to obtain a scattering light spot; when the signal bandwidth of the scattering light spot is less than or equal to the bandwidth threshold value, the surface of the measured object is a weak scattering interface, and the displacement of the scattering light spot on the CCD is measured by adopting an average weighted gravity center method; when the signal bandwidth of the scattering light spot is larger than a bandwidth threshold value, the surface of the measured object is indicated to be a strong scattering cross section, and the displacement of the scattering light spot on the CCD is measured by adopting a correlation method; and calculating the displacement of the measured object according to the displacement of the scattering light spots on the CCD.
In addition, among the existing optical measurement methods, digital image correlation methods have been widely studied and applied due to their comprehensive advantages of simple installation, abundant measurement indexes and information content, numerous types of measurable materials, suitability for measurement in various scales and under various conditions, high accuracy, and the like. In the field of experimental mechanics, two-dimensional digital image correlation is a widely used method for quantitatively measuring the displacement of a planar object in the x and y directions. The displacement and strain information in the image plane of the object region of interest is obtained by analyzing the digital images of the surface of the measured object before and after deformation, and the sub-pixel precision is achieved. However, the two-dimensional digital image correlation is limited to the measurement of displacement in the in-plane x and y directions, and displacement in the optical axis z direction cannot be obtained.
Therefore, how to obtain the three-dimensional vector displacement of the object in a larger measurement range quickly and easily by a simple device is an urgent problem to be solved, and a technical solution needs to be provided to improve the technical problem.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide a three-dimensional displacement compact measuring device, a three-dimensional displacement compact measuring method and a three-dimensional displacement compact measuring medium for a scattered light field holographic range.
The invention provides a three-dimensional displacement compact measuring device for a scattered light field holographic range, which comprises a first laser, a second laser, a first spectroscope, a second spectroscope, a convergent lens, a pinhole, a first plane mirror, a second plane mirror, a third spectroscope and a camera;
the first spectroscope is over against the laser emitting ports of the first laser and the second laser to combine two beams of laser, the second spectroscope is positioned on the combined beam light path of the first spectroscope, the convergent lens, the pinhole and the first plane mirror are sequentially arranged in a row and positioned on the reflected light path of the second spectroscope, the second plane mirror is positioned on the reflected light path of the first plane mirror, the third spectroscope is positioned at the intersection position of the transmission light path of the second spectroscope and the reflected light path of the second plane mirror, the object to be detected is positioned on the transmission light path of the third spectroscope, and the camera is positioned on the combined beam light path of the reflected light of the object to be detected and the reflected light of the second plane mirror.
Preferably, a neutral attenuation sheet is arranged between the second spectroscope and the converging lens.
Preferably, an imaging lens is arranged between the third spectroscope and the object to be measured.
Preferably, a phase shift device is arranged between the second plane mirror and the third beam splitter.
Preferably, the second beam splitter is replaced by a polarization beam splitting unit, the polarization beam splitting unit comprises a polarization beam splitter, a first half-wave plate and a second half-wave plate, the polarization beam splitter is located at the position of the second beam splitter, the first half-wave plate is arranged between the first beam splitter and the polarization beam splitter, and the second half-wave plate is arranged between the polarization beam splitter and the converging lens.
The invention also provides a measuring method of the scattered light field holographic range three-dimensional displacement compact measuring device, the method applies the scattered light field holographic range three-dimensional displacement compact measuring device, and the method comprises the following steps:
step S1: light emitted by the first laser and light emitted by the second laser are incident to the second spectroscope after being combined by the first spectroscope and are divided into two paths: the light beam transmitted by the second spectroscope penetrates through the third spectroscope and then irradiates the surface of the object to be measured, and the light beam is reflected by the surface of the object to be measured to form a measuring light beam; the light beam reflected by the second spectroscope is filtered by a convergent lens and a pinhole and then reflected by a first plane mirror and a second plane mirror to form a reference light beam; the measuring beam and the reference beam are interfered after being combined by the third beam splitter, and a hologram is formed on a photosensitive surface of the camera;
step S2: before the displacement of the object to be detected changes, a first laser and a second laser are used for respectively irradiating the object to be detected, the two holograms H1 and H2 are obtained through recording by a camera, light field reconstruction is carried out by utilizing the recorded two holograms, two single-wavelength phase diagrams of the surface reflected light field of the object to be detected before the displacement is further obtained, the appearance of the object to be detected before the displacement is calculated according to a double-wavelength phase synthesis formula, and the intensity diagram of the surface reflected light field of the object to be detected before the displacement is calculated by using a hologram H1 or a hologram H2;
step S3: after the displacement of the object to be detected changes, a first laser and a second laser are used for respectively irradiating the object to be detected, the two holograms H3 and H4 are obtained through recording by a camera, light field reconstruction is carried out by utilizing the two recorded holograms, two single-wavelength phase diagrams of the surface reflection light field of the object to be detected after the object to be detected displaces are further obtained, and then the shape of the object to be detected after the displacement is calculated according to a double-wavelength phase synthesis formula; using the hologram H3 or H4 obtained by the irradiation of the laser with the same wavelength in the step S2 to calculate the intensity graph of the surface reflected light field of the object after the object is displaced;
step S4: subtracting the appearances of the object to be measured before and after the displacement to obtain the displacement along the direction z of the optical axis; processing intensity graphs of light fields reflected by the surface of the object to be measured before and after the object to be measured displaces, and calculating the displacement of the object to be measured in the x direction and the y direction perpendicular to the optical axis direction;
step S5: and combining the displacement of the object to be measured along the direction z of the optical axis with the displacement of the object to be measured along the directions x and y perpendicular to the optical axis to obtain the three-dimensional vector displacement of the object to be measured.
Preferably, the step S2 includes the steps of:
step S2.1: selecting a coordinate point P1 to be measured on the intensity graph before displacement;
step S2.2: with a selected coordinate point P1 to be detected as a center, defining a region R1 with the size of (2M +1) × (2M +1) pixels, wherein M is a positive integer and is determined by the size of the interested sub-region;
step S2.3: arbitrarily defining a region R2 of size (2M +1) × (2M +1) centered on the coordinate point Pi on the shifted intensity map;
step S2.4: calculating the similarity of the regions R1 and R2;
step S2.5: changing the coordinate value of the coordinate point Pi in the step S2.3, and repeating the steps S2.3-S2.4 until i traverses all pixels in the intensity map after displacement to find out an area R2 with the highest similarity to the area R1;
step S2.6: calculating center coordinates P2 of the region R2;
step S2.7: subtracting the coordinates of P2 and P1 to obtain the displacement of the P1 point in the x direction and the y direction perpendicular to the optical axis;
step S2.8: and (5) repeatedly executing the step (S2.1) to the step (S2.7) until all pixel points in the intensity graph before the whole displacement are traversed, namely obtaining the displacement in the x direction and the y direction of the vertical optical axis corresponding to all the pixel points.
Preferably, the inclination angles of the first plane mirror and the second plane mirror are adjusted, an included angle is formed between the reflected reference beam and the measurement beam, and the scattered light field is extracted from the hologram by a fourier transform method.
Preferably, a phase shifting device is added in an optical path of the light beam reflected by the first plane mirror and incident to the third beam splitter, the reference light beam is subjected to phase shifting, and a scattered light field is extracted from the hologram through a multi-step phase shifting calculation method.
The invention also provides a computer-readable storage medium having stored thereon a computer program which, when being executed by a processor, carries out the steps of the method as set forth above.
Compared with the prior art, the invention has the following beneficial effects:
1. the measuring device solves the problems of complex system optical path structure and high cost caused by using a plurality of sets of measuring devices to measure displacements with different dimensions respectively in the existing three-dimensional vector displacement measuring technology, provides a measuring method only using one path of measuring light beam in a multiplexing way, combines the measuring method with a two-dimensional digital image related technology, efficiently utilizes all information of one set of measuring system, effectively reduces the cost and greatly simplifies the complexity of the measuring system and the operation process;
2. the invention adopts a dual-wavelength light path structure to realize light path multiplexing, and can effectively enlarge the measurement range of the displacement in the out-of-plane direction;
3. compared with the existing measuring device, the measuring device of the invention has more scientific and reasonable structural design, simpler and more convenient use, more compact designed light path and more suitability for integration;
4. the measuring device adopts the single lens, thereby not only realizing the light spot amplification, but also realizing the imaging function. The light spot can be amplified according to actual requirements, and the measurement range of the larger light spot is realized;
5. the measuring method has the characteristics of full-field and non-contact measurement, and can realize the nondestructive detection of the to-be-measured piece;
6. the measuring method combines a nanometer-level high-precision scattered light field measuring technology with a sub-pixel-level high-precision digital image correlation technology, and has the advantages of high efficiency, high speed, high measuring precision and dynamic measurement; first, the present invention integrates two independent technologies into one hardware system, and the two technologies have their own hardware systems, including independent cameras and optical imaging systems, respectively. The invention is based on only one set of holographic hardware system, and does not adopt an independent hardware system of digital image correlation technique, but utilizes the digital image correlation technique to process speckle intensity images which are not utilized by digital holography before, thus organically combining two independent techniques on one hardware system. Second, digital image correlation techniques deal with laser speckle images in the present invention. Whereas previous digital image correlation techniques processed intensity images in natural light or white light, the key content of the processing was texture of objects in the intensity images or artificially painted speckle. Laser speckle is different from the previously processed features of these digital image correlation techniques.
7. The measuring method can realize synchronous measurement of the three-dimensional vector displacement of the scattering surface object, and solves the limitation that the traditional optical measuring method can only measure the object on the surface of the mirror surface. Three-dimensional displacement measurement of curved objects requires three-dimensional topography information of the object. Three-dimensional topography measurements of scattering surface objects are more difficult than specular objects. The particle height change of the scattering surface object exceeds the laser wavelength, so that the scattering surface object is difficult to measure by a simple digital holographic system, an additional three-dimensional shape measuring system is often needed, the complexity of a measuring scheme is caused, and the difficulty and the further complexity of the scheme are caused by data fusion of multiple sets of systems. However, the three-dimensional topography of specular objects at heights in and below micrometers can be measured using a laser holographic system. Thus making measurement of the three-dimensional vector displacement of the scattering surface object difficult. The present invention solves this problem by multiplexing the same set of optical paths, using a holographic system of two lasers.
Drawings
Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments with reference to the following drawings:
FIG. 1 is a schematic diagram of a large-range three-dimensional displacement compact measuring device for scattered light field holography according to the invention;
FIG. 2 is a block diagram of a compact measuring apparatus for holographic large-range three-dimensional displacement of scattered light field in embodiment 1 of the present invention;
fig. 3A is a hologram recorded by the CCD before the object to be measured is displaced and irradiated by the first laser in embodiment 1 of the present invention;
fig. 3B is a hologram recorded by the CCD and respectively irradiated by the second laser before the object to be measured is displaced in embodiment 1 of the present invention;
fig. 4A is a hologram which is recorded by the CCD and irradiated by the first laser after the object to be measured is displaced in embodiment 1 of the present invention;
fig. 4B is a hologram which is recorded by the CCD and irradiated by the second laser after the object to be measured is displaced in embodiment 1 of the present invention;
FIG. 5 is a diagram of a dual wavelength synthetic wrapped phase before displacement of an object to be measured in embodiment 1 of the present invention;
fig. 6 is a graph of a measurement result of the object to be measured along the optical axis z direction in embodiment 1 of the present invention;
fig. 7A is an intensity chart of the CCD recorded before the object to be measured is displaced, which is irradiated by the first laser in embodiment 1 of the present invention;
fig. 7B is an intensity chart of the CCD recorded before the object to be measured is displaced, which is irradiated by the second laser in embodiment 1 of the present invention;
fig. 8A is a graph showing a measurement result of in-plane displacement of the object to be measured along the x direction perpendicular to the optical axis in embodiment 1 of the present invention;
fig. 8B is a graph showing a measurement result of in-plane displacement of the object to be measured along the y direction perpendicular to the optical axis in embodiment 1 of the present invention;
FIG. 9 is a structural diagram of a compact measuring device for large-range three-dimensional displacement of scattered light field holography in embodiment 2 of the present invention;
FIG. 10 is a view showing an internal structure of a polarization splitting unit according to the present invention;
FIG. 11 is a structural diagram of a large-scale three-dimensional displacement compact measuring device for scattered light field holography in embodiment 3 of the present invention;
fig. 12 is a structural diagram of a large-range three-dimensional displacement compact measuring device for scattered light field holography in embodiment 4 of the invention.
Wherein:
First half-wave plate 141 of condenser lens 5
Object to be measured 10
Detailed Description
The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that it would be obvious to those skilled in the art that various changes and modifications can be made without departing from the spirit of the invention. All falling within the scope of the present invention.
The invention provides a three-dimensional displacement compact measuring device, a three-dimensional displacement compact measuring method and a three-dimensional displacement compact measuring medium for a scattered light field holographic range. The invention is based on the scattered light field measurement technology and combines the two-dimensional digital image correlation technology to dynamically and synchronously measure the three-dimensional vector displacement of an object. The invention can be applied to displacement measurement of objects with mirror surfaces or rough surfaces, and realizes synchronous measurement of three-dimensional vector displacement or deformation of the objects.
Example 1
As shown in fig. 2, the large-scale three-dimensional displacement compact measuring device for scattered light field holography used in the present embodiment comprises: the device comprises a first laser 1, a second laser 2, a first spectroscope 3, a second spectroscope 4, a convergent lens 5, a pinhole 6, a first plane mirror 7, a second plane mirror 8, a third spectroscope 9, an object to be measured 10, a camera 11, a neutral attenuation sheet 12 and an imaging lens 13.
The first laser 1 generates laser light 1a, the second laser 2 generates laser light 2a, and the laser light 1a and the laser light 2a are input to the first beam splitter 3 and then combined.
The first laser 1 and the second laser 2 are coherent light sources, and in the specific design of the invention, the first laser 1 provides space light with the central wavelength of 532nm, and the second laser 2 provides space light with the central wavelength of 526.5 nm.
The first beam splitter 3, the second beam splitter 4 and the third beam splitter 9 are optical devices that can split a light beam into two, achieving 50% transmission and 50% reflection. The first spectroscope 3, the second spectroscope 4, and the third spectroscope 9 are the same in structure and function, and the second spectroscope 4 will be described as an example. The second beam splitter 4 is configured to receive the spatial light 3a combined by the first beam splitter 3, and split the spatial light into spatial light 4a and spatial light 4b for output. Wherein the transmitted light 4b enters the measurement light path and the reflected light 4a enters the reference light path.
The neutral attenuation sheet 12 is used for adjusting the intensity of the reference light path, and further adjusting the light intensity ratio of the measuring light to the reference light to obtain a high-quality hologram.
The converging lens 5 and the pinhole 6 together constitute a spatial filtering unit. The condenser lens 5 condenses the spatial light 5a attenuated by the neutral attenuation plate 12 to a point where a pinhole is provided to eliminate stray light so that the point is closer to an ideal point light source, wherein the front focal point of the condenser lens coincides with the point.
The first plane mirror 7 and the second plane mirror 8 are used for reflecting the light beams and deflecting the light propagation direction. The first flat mirror 7 and the second flat mirror 8 in this embodiment have the same structure, and the first flat mirror 7 is used to deflect the reference light 7a coming out of the spatial filtering unit by about 90 ° in space, so that the reference light is reflected after passing through the second flat mirror 8. The second plane mirror 8 is used to adjust the angle between the reference light and the measuring beam by using an off-axis digital holographic structure.
The imaging lens 13 functions to enlarge and image. Firstly, the space light 11a transmitted through the third beam splitter 9 can enlarge the light spot after passing through the imaging lens 13, so that the range of the light spot covering the object to be measured 10 is improved, then the measurement light 12b carrying the target information is imaged behind the imaging lens 13 and is reflected by the third beam splitter 9 and recorded by the camera 11.
The camera 11 is used for recording holograms. The camera 11 includes, but is not limited to, a CCD, a CMOS, and the like.
In this embodiment, the spatial light 4b transmitted by the second beam splitter 4 passes through the third beam splitter 9, the imaging lens 13, and the object to be measured 10, and then is reflected by the imaging lens 13 and the third beam splitter 9. This portion may be referred to as the measuring beam.
In this embodiment, the spatial light 4a reflected by the second beam splitter 4 passes through the neutral attenuator 12, the condenser lens 5, the pinhole 6, the first plane mirror 7, the second plane mirror 8, and the third beam splitter 9. This portion may be referred to as the reference beam.
The reference beam interferes with the measuring beam and the resulting hologram is recorded by the photosensitive surface of the camera 11 to obtain a digital hologram.
The light path working principle of the scattering light field holographic large-range three-dimensional displacement compact measuring device used in the embodiment is as follows: the laser 1 generates laser 1a, the laser 2 generates laser 2a, the laser 2a passes through the first beam splitter 3, the laser 2a is combined into laser 3a, the laser 3a enters the second beam splitter 4 and is divided into two beams: one beam of light 4b is transmitted through the third beam splitter 9 to become 11a, the light spot is amplified by the imaging lens 13 and then irradiates the object to be measured 10, and the light 12b reflected by the surface of the object to be measured 10 is focused by the imaging lens 13, reflected to the photosensitive surface of the digital camera 11 by the third beam splitter 9 and recorded by the camera 11; the other beam of reflected light 4a is attenuated by the neutral filter 12, and then is converged by the converging lens 5, the pinhole 6 is arranged at the light converging point, so that the beam quality can be effectively improved to obtain 7a, then the 7a is reflected by the first plane mirror 7 and the second plane mirror 8 to form 9a to reach the third beam splitter 9, and the 9a is transmitted by the third beam splitter 9 to reach the light sensing surface of the camera 11, is interfered with the measuring beam and is recorded by the camera 11.
The holographic large-range three-dimensional displacement compact measuring device for the scattered light field provided by the embodiment can dynamically measure synchronous three-dimensional deformation or displacement of an object, and the specific measuring method comprises the following steps:
step 1: the object 10 to be measured is placed in the measuring beam path.
Step 2: before the displacement of the object 10 to be measured, the holograms of the object 10 to be measured when two lasers with different wavelengths are irradiated are respectively recorded by the CCD, as shown in fig. 3.
And step 3: and applying displacement to the object to be measured 10, in this embodiment, applying 5 micrometers of loading to the object to be measured 10 along the optical axis direction by using PZT.
And 4, step 4: fig. 4 shows a hologram obtained by using a CCD to record the displacement of the object 10 under test when two lasers with different wavelengths are irradiated.
And 5: calculating the scattered light field of the object to be measured 10 under the dual-wavelength respective irradiation: and performing Fourier transform on the hologram before displacement, intercepting a primary frequency spectrum by a spatial filtering method, shifting the frequency to the center, multiplying the frequency by a transfer function determined by the corresponding wavelength and the reconstruction distance, and performing inverse Fourier transform to obtain the complex amplitude of the scattered light field of the object to be measured under different wavelengths before displacement.
Step 6: and (5) repeating the step (5) to obtain the complex amplitude of the scattered light field of the object to be measured under different wavelengths after displacement.
And 7: extracting phase distribution of scattered light field of object to be measured 10 under irradiation of different wavelengths from complex amplitude before displacement
And
and 8: repeating the step 7, extracting the phase distribution of the scattered light field after the displacement of the object 10 to be measured when the object is irradiated by different wavelengths from the complex amplitude
And
and step 9: obtaining a dual-wavelength synthetic wrapping phase delta phi 1 of the object to be measured 10 before displacement through a relational expression, as shown in fig. 5:
step 10: and 9, repeating the step 9, and obtaining the dual-wavelength synthetic wrapping phase delta phi 2 of the object to be detected 10 after displacement according to the following relational expression:
step 11: using the relational expression:
the phase information is converted into height information, so that the appearances of the object 10 to be measured before and after the displacement are obtained respectively.
Step 12: the out-of-plane displacement of the object 10 along the z-axis can be obtained by subtracting the shape before the displacement from the shape after the displacement of the object 10, as shown in fig. 6.
Step 13: extracting intensity distribution I of scattered light field before and after displacement of object to be detected 10 under irradiation of any wavelength from complex amplitude1And I2As shown in fig. 7.
Step 14: using 2D-DIC technique to I1And I2The processing is performed to obtain the in-plane displacement x, y in the normal direction of the entire image area, as shown in fig. 8.
Step 15: and combining the out-of-plane displacement z along the normal direction and the in-plane displacement x and y vertical to the optical axis direction to obtain a three-dimensional displacement measurement result of the object.
Example 2
Unlike embodiment 1, the second beam splitter 4 in embodiment 1 is replaced with a polarization splitting unit 14 in this embodiment.
As shown in fig. 9, the scattered light field holographic large-scale three-dimensional displacement compact measuring device used in the present embodiment includes: the device comprises a first laser 1, a second laser 2, a first spectroscope 3, a polarization beam splitting unit 14, a neutral attenuation sheet 12, a convergent lens 5, a pinhole 6, a first plane mirror 7, a second plane mirror 8, a third spectroscope 9, an object to be measured 10, a camera 11 and an imaging lens 13.
The internal structure of the polarization beam splitting unit 14 is shown in fig. 10, and includes a first half-wave plate 141, a polarization beam splitter 142, and a second half-wave plate 143.
The polarization beam splitting unit 14 is configured to receive the light source 3a emitted from the first beam splitter 3 after being combined, split the light source into spatial light 4a and spatial light 4b, and output the spatial light, and is responsible for adjusting the light intensity ratio of the two paths of light, which is generally 1:5 to 5: 1.
The laser beam 3a combined by the first beam splitter is incident on the polarization beam splitter 14 and is split into two beams orthogonal in polarization direction: reflected light and transmitted light; wherein, the reflected light becomes 4a after passing through the second half-wave plate 143 and enters the reference light path, and the transmitted light 4b enters the measuring light path.
In this embodiment, the light intensity ratio between the spatial light beams 4a and 4b can be changed to be generally 1:5 to 5:1 by rotating and adjusting the first half-wave plate 141 in the polarization splitting unit 14, so as to perform the function of adjusting the light intensity ratio between the measuring beam and the reference beam, and obtain a high-quality hologram. By rotating the second half-wave plate 143, the polarization directions of the measuring beam 4a and the reference beam 4b are made coincident in order to enable the two to interfere.
The light path working principle of the scattering light field holographic large-range three-dimensional displacement compact measuring device used in the embodiment is as follows: the first laser 1 generates laser 1a, the second laser 2 generates laser 2a, the laser 2a passes through the first beam splitter 3 and then is combined into laser 3a, and the laser 3a is incident on the polarization beam splitter unit 14 and then is divided into two paths of light with adjustable light intensity ratio: one beam of light 4b is transmitted through the third beam splitter 9 to become 11a, the light spot is amplified by the imaging lens 13 and then irradiates the object to be measured 10, and the light 12b reflected by the surface of the object to be measured 10 is focused by the imaging lens 13, reflected to the photosensitive surface of the camera 11 by the third beam splitter 9 and recorded by the camera 11. The other beam of reflected light 4a is subjected to light intensity attenuation by a neutral attenuation sheet 12, and then is converged by a converging lens 5, a pinhole 6 is arranged at the light convergence point, so that the light beam quality can be effectively improved to obtain 7a, then the 7a is reflected by a first plane mirror 7 and a second plane mirror 8 to form 9a to reach a third beam splitter 9, and the 9a reaches the light sensing surface of the camera after being transmitted by the third beam splitter 9, is interfered with the measuring light beam, and is recorded by a camera 11.
Example 3
Unlike embodiment 1, the present embodiment employs the spectroscopic plate 15 instead of the third spectroscope in embodiment 1.
As shown in fig. 11, the scattered light field holographic large-range three-dimensional displacement compact measuring device used in the present embodiment includes: the device comprises a first laser 1, a second laser 2, a first spectroscope 3, a polarization beam splitting unit 14, a neutral attenuation sheet 12, a convergent lens 5, a pinhole 6, a first plane mirror 7, a second plane mirror 8, a beam splitting flat plate 15, an object to be measured 10, a camera 11 and an imaging lens 13.
The beam splitting plate 15 is used for interfering and combining the measuring beam 13a reflected by the object to be measured 10 and the reference beam 9 a.
The light path working principle of the scattering light field holographic large-range three-dimensional displacement compact measuring device used in the embodiment is as follows: the laser 1 generates laser 1a, the laser 2 generates laser 2a, the laser 2a passes through the first beam splitter 3, the laser 2a is combined into laser 3a, the laser 3a enters the second beam splitter 4 and is divided into two beams: one beam of light 4b becomes 11a after transmitting through the light splitting plate 15, irradiates the object to be measured 10 after the light spot is amplified by the imaging lens 13, and is reflected to the photosensitive surface of the digital camera 11 by the light splitting plate 15 after the light 12b reflected by the surface of the object to be measured 10 is focused by the imaging lens 13 and is recorded by the camera 11; the other beam of reflected light 4a is subjected to light intensity attenuation through a neutral attenuation sheet 12, then is converged through a converging lens 5, a pinhole 6 is placed at the light convergence point, the light beam quality can be effectively improved to obtain 7a, then the 7a is reflected through a first flat mirror 7 and a second flat mirror 8 to form 9a, the 9a reaches a light splitting flat plate 15, the 9a penetrates through the light splitting flat plate 15 and then reaches a light sensing surface of a camera 11, interference is carried out on the 9a and the measuring light beam, and the measuring light beam is recorded by the camera.
Example 4
Unlike embodiment 1, in this embodiment, a phase shift device 16 is added between the first plane mirror 8 and the third beam splitter 9 of the reference optical path.
As shown in fig. 12, the scattered light field holographic large-range three-dimensional displacement compact measuring device used in the present embodiment includes: the device comprises a first laser 1, a second laser 2, a first spectroscope 3, a second spectroscope 4, a convergent lens 5, a pinhole 6, a first plane mirror 7, a second plane mirror 8, a third spectroscope 9, an object to be measured 10, a camera 11, a neutral attenuation sheet 12, an imaging lens 13 and a phase shift device 16.
The phase shifting device 16 is used to shift the phase of the reference light and then extract the scattered light field from the hologram by a multi-step phase shift calculation method.
The light path working principle of the scattering light field holographic large-range three-dimensional displacement compact measuring device used in the embodiment is as follows: the laser 1 generates laser 1a, the laser 2 generates laser 2a, the laser 2a passes through the first beam splitter 3, the laser 2a is combined into laser 3a, the laser 3a enters the second beam splitter 4 and is divided into two beams: one beam of light 4b is transmitted through the third beam splitter 9 to become 11a, the light spot is amplified by the imaging lens 13 and then irradiates the object to be measured 10, and the light 12b reflected by the surface of the object to be measured 10 is focused by the imaging lens 13, reflected to the photosensitive surface of the camera 11 by the third beam splitter 9 and recorded by the camera 11; the other beam of reflected light 4a is subjected to light intensity attenuation through a neutral attenuation sheet 12, then is converged through a converging lens 5, a pinhole 6 is arranged at the light converging point, the light beam quality can be effectively improved to obtain 7a, then the 7a is reflected through a first plane mirror 7 and a second plane mirror 8 to form 9a, the 9a is subjected to phase shift through a phase shift device 16, reaches a light sensing surface of a camera 11 after being transmitted through a third beam splitter 9, is interfered with the measuring light beam, and is recorded by the camera.
The invention also provides a computer-readable storage medium having stored thereon a computer program which, when being executed by a processor, carries out the steps of the method as set forth above.
The measuring device solves the problems of complex system optical path structure and high cost caused by using a plurality of sets of measuring devices to measure displacements with different dimensions respectively in the existing three-dimensional vector displacement measuring technology, provides a measuring method only using one path of measuring light beam in a multiplexing way, combines the measuring method with a two-dimensional digital image related technology, efficiently utilizes all information of one set of measuring system, effectively reduces the cost and greatly simplifies the complexity of the measuring system and the operation process; and the optical path structure with double wavelengths is adopted, so that optical path multiplexing is realized, and the measuring range of the displacement in the out-of-plane direction can be effectively enlarged.
Compared with the existing measuring device, the measuring device of the invention has more scientific and reasonable structural design, simpler and more convenient use, more compact designed light path and more suitability for integration; the measuring device adopts the single lens, thereby not only realizing the light spot amplification, but also realizing the imaging function. The light spot can be amplified according to actual requirements, and the measurement range of the larger light spot is realized; the measuring method has the characteristics of full-field and non-contact measurement, and can realize the nondestructive detection of the to-be-measured piece.
The measuring method combines a nanometer-level high-precision scattered light field measuring technology with a sub-pixel-level high-precision digital image correlation technology, and has the advantages of high efficiency, high speed, high measuring precision and dynamic measurement; first, the present invention integrates two independent technologies into one hardware system, and the two technologies have their own hardware systems, including independent cameras and optical imaging systems, respectively. The invention is based on only one set of holographic hardware system, and does not adopt an independent hardware system of digital image correlation technique, but utilizes the digital image correlation technique to process speckle intensity images which are not utilized by digital holography before, thus organically combining two independent techniques on one hardware system. Second, digital image correlation techniques deal with laser speckle images in the present invention. Whereas previous digital image correlation techniques processed intensity images in natural light or white light, the key content of the processing was texture of objects in the intensity images or artificially painted speckle. Laser speckle is different from the previously processed features of these digital image correlation techniques.
The measuring method can realize synchronous measurement of the three-dimensional vector displacement of the scattering surface object, and solves the limitation that the traditional optical measuring method can only measure the object on the surface of the mirror surface. Three-dimensional displacement measurement of curved objects requires three-dimensional topography information of the object. Three-dimensional topography measurements of scattering surface objects are more difficult than specular objects. The particle height change of the scattering surface object exceeds the laser wavelength, so that the scattering surface object is difficult to measure by a simple digital holographic system, an additional three-dimensional shape measuring system is often needed, the complexity of a measuring scheme is caused, and the difficulty and the further complexity of the scheme are caused by data fusion of multiple sets of systems. However, the three-dimensional topography of specular objects at heights in and below micrometers can be measured using a laser holographic system. Thus making measurement of the three-dimensional vector displacement of the scattering surface object difficult. The present invention solves this problem by multiplexing the same set of optical paths, using a holographic system of two lasers.
In the description of the present application, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the present application and simplifying the description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present application.
The foregoing description of specific embodiments of the present invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes or modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention. The embodiments and features of the embodiments of the present application may be combined with each other arbitrarily without conflict.
Claims (10)
1. A three-dimensional displacement compact measuring device for a holographic range of a scattered light field is characterized by comprising a first laser (1), a second laser (2), a first spectroscope (3), a second spectroscope (4), a convergent lens (5), a pinhole (6), a first plane mirror (7), a second plane mirror (8), a third spectroscope (9) and a camera (11);
the laser beam combining device comprises a first spectroscope (3), a second spectroscope (4), a converging lens (5), a pinhole (6) and a first plane mirror (7), wherein the first spectroscope (3) is over against laser emitting ports of a first laser (1) and a second laser (2) to combine two laser beams, the second spectroscope (4) is positioned on a beam combining light path of the first spectroscope (3), the converging lens (5), the pinhole (6) and the first plane mirror (7) are sequentially arranged in a row and positioned on a reflecting light path of the second spectroscope (4), the second plane mirror (8) is positioned on the reflecting light path of the first plane mirror (7), a third spectroscope (9) is positioned at the intersection position of a transmitting light path of the second spectroscope (4) and a reflecting light path of the second plane mirror (8), an object to be measured (10) is positioned on a transmitting light path of the third spectroscope (9), and a camera (11) is positioned on the beam combining light path of the reflecting light of the object to be measured (10) and the reflecting light of the first plane mirror (8).
2. The scattered light field holographic range three-dimensional displacement compact measuring device according to claim 1, characterized in that a neutral attenuation sheet is arranged between the second beam splitter (4) and the converging lens (5).
3. The scattered light field holographic range three-dimensional displacement compact measuring device according to claim 1, characterized in that an imaging lens is arranged between the third beam splitter (9) and the object (10) to be measured.
4. The scattered light field holographic range three-dimensional displacement compact measuring device according to claim 1, characterized in that a phase shifting device is arranged between the second plane mirror (4) and the third beam splitter (9).
5. The scattered light field holographic range three-dimensional displacement compact measuring device according to claim 1, characterized in that the second beam splitter (4) is replaced by a polarizing beam splitter unit comprising a polarizing beam splitter, a first half wave plate and a second half wave plate, the polarizing beam splitter being located at the position of the second beam splitter (4), the first half wave plate being arranged between the first beam splitter (3) and the polarizing beam splitter, the second half wave plate being arranged between the polarizing beam splitter and the converging lens (5).
6. A measuring method of a scattered light field holographic range three-dimensional displacement compact measuring device, which is characterized in that the method applies the scattered light field holographic range three-dimensional displacement compact measuring device as claimed in any one of claims 1 to 5, and the method comprises the following steps:
step S1: light emitted by the first laser and light emitted by the second laser are incident to the second spectroscope after being combined by the first spectroscope and are divided into two paths: the light beam transmitted by the second spectroscope penetrates through the third spectroscope and then irradiates the surface of the object to be measured, and the light beam is reflected by the surface of the object to be measured to form a measuring light beam; the light beam reflected by the second spectroscope is filtered by a convergent lens and a pinhole and then reflected by a first plane mirror and a second plane mirror to form a reference light beam; the measuring beam and the reference beam are interfered after being combined by the third beam splitter, and a hologram is formed on a photosensitive surface of the camera;
step S2: before the displacement of the object to be detected changes, a first laser and a second laser are used for respectively irradiating the object to be detected, the two holograms H1 and H2 are obtained through recording by a camera, light field reconstruction is carried out by utilizing the recorded two holograms, two single-wavelength phase diagrams of the surface reflected light field of the object to be detected before the displacement is further obtained, the appearance of the object to be detected before the displacement is calculated according to a double-wavelength phase synthesis formula, and the intensity diagram of the surface reflected light field of the object to be detected before the displacement is calculated by using a hologram H1 or a hologram H2;
step S3: after the displacement of the object to be detected changes, a first laser and a second laser are used for respectively irradiating the object to be detected, the two holograms H3 and H4 are obtained through recording by a camera, light field reconstruction is carried out by utilizing the two recorded holograms, two single-wavelength phase diagrams of the surface reflection light field of the object to be detected after the object to be detected displaces are further obtained, and then the shape of the object to be detected after the displacement is calculated according to a double-wavelength phase synthesis formula; using the hologram H3 or H4 obtained by the irradiation of the laser with the same wavelength in the step S2 to calculate the intensity graph of the surface reflected light field of the object after the object is displaced;
step S4: subtracting the appearances of the object to be measured before and after the displacement to obtain the displacement along the direction z of the optical axis; processing intensity graphs of light fields reflected by the surface of the object to be measured before and after the object to be measured displaces, and calculating the displacement of the object to be measured in the x direction and the y direction perpendicular to the optical axis direction;
step S5: and combining the displacement of the object to be measured along the direction z of the optical axis with the displacement of the object to be measured along the directions x and y perpendicular to the optical axis to obtain the three-dimensional vector displacement of the object to be measured.
7. The measurement method of the scattered light field holographic range three-dimensional displacement compact measurement device according to claim 6, characterized in that: the step S2 includes the following steps:
step S2.1: selecting a coordinate point P1 to be measured on the intensity graph before displacement;
step S2.2: with a selected coordinate point P1 to be detected as a center, defining a region R1 with the size of (2M +1) × (2M +1) pixels, wherein M is a positive integer and is determined by the size of the interested sub-region;
step S2.3: arbitrarily defining a region R2 of size (2M +1) × (2M +1) centered on the coordinate point Pi on the shifted intensity map;
step S2.4: calculating the similarity of the regions R1 and R2;
step S2.5: changing the coordinate value of the coordinate point Pi in the step S2.3, and repeating the steps S2.3-S2.4 until i traverses all pixels in the intensity map after displacement to find out an area R2 with the highest similarity to the area R1;
step S2.6: calculating center coordinates P2 of the region R2;
step S2.7: subtracting the coordinates of P2 and P1 to obtain the displacement of the P1 point in the x direction and the y direction perpendicular to the optical axis;
step S2.8: and (5) repeatedly executing the step (S2.1) to the step (S2.7) until all pixel points in the intensity graph before the whole displacement are traversed, namely obtaining the displacement in the x direction and the y direction of the vertical optical axis corresponding to all the pixel points.
8. The measurement method of the scattered light field holographic range three-dimensional displacement compact measurement device according to claim 6, characterized in that: and adjusting the inclination angles of the first plane mirror and the second plane mirror, forming an included angle between the reflected reference beam and the measurement beam, and extracting a scattered light field from the hologram by a Fourier transform method.
9. The measurement method of the scattered light field holographic range three-dimensional displacement compact measurement device according to claim 6, characterized in that: and adding a phase shifting device in an optical path of the light beam reflected by the first plane mirror and incident to the third beam splitter, shifting the phase of the reference light beam, and extracting a scattered light field from the hologram by a multi-step phase shifting calculation method.
10. A computer-readable storage medium, in which a computer program is stored which, when being executed by a processor, carries out the steps of the method of any one of claims 5 to 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111276683.XA CN113946116A (en) | 2021-10-29 | 2021-10-29 | Three-dimensional displacement compact measuring device, method and medium for scattered light field holographic range |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111276683.XA CN113946116A (en) | 2021-10-29 | 2021-10-29 | Three-dimensional displacement compact measuring device, method and medium for scattered light field holographic range |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113946116A true CN113946116A (en) | 2022-01-18 |
Family
ID=79337160
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111276683.XA Pending CN113946116A (en) | 2021-10-29 | 2021-10-29 | Three-dimensional displacement compact measuring device, method and medium for scattered light field holographic range |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113946116A (en) |
-
2021
- 2021-10-29 CN CN202111276683.XA patent/CN113946116A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US11644791B2 (en) | Holographic imaging device and data processing method therefor | |
| CN100485312C (en) | Methods and apparatus for wavefront manipulations and improved three-dimension measurements | |
| US6885460B2 (en) | Apparatus for and method of measuring surface shape of an object | |
| TWI797377B (en) | Surface shape measuring device and surface shape measuring method | |
| CN106768280A (en) | A kind of vibration detection device based on multi-wavelength lensless fourier transform digital hologram | |
| CN106568395A (en) | Digital grating and physical grating combined tiny object surface three-dimensional measurement system | |
| CN108895986A (en) | Microscopic three-dimensional topography measurement device based on striped projection | |
| CN108562241B (en) | Digital holographic flexible measurement device and method based on optical fiber bundle | |
| CN112525104A (en) | Digital holographic three-dimensional shape measuring device and method | |
| CN112525097B (en) | Method for measuring three-dimensional deformation of object based on multiple sensors | |
| CN113805454A (en) | Scattered light field holographic three-dimensional displacement measuring device, method and medium | |
| KR20170023363A (en) | System and method for measuring high height by digital holography microscope | |
| CN108088368A (en) | Reflective off-axis digital holography apparatus and method based on light splitting pupil | |
| CN116625269A (en) | Absolute detection method for plane surface shape of large-caliber optical element | |
| CN113946116A (en) | Three-dimensional displacement compact measuring device, method and medium for scattered light field holographic range | |
| CN104634253A (en) | Three-dimensional displacement measuring method based on morphology correlation calculation | |
| CN216792690U (en) | Three-dimensional displacement compact measuring device for scattered light field holographic range | |
| Picart et al. | Basic fundamentals of digital holography | |
| CN113946117A (en) | Three-dimensional displacement measuring device, method and medium for scattered light field holographic range | |
| CN216792689U (en) | Scattered light field holographic three-dimensional displacement measuring device | |
| CN216118401U (en) | Scattered light field holographic three-dimensional displacement compact measuring device | |
| CN113946115A (en) | Scattered light field holographic three-dimensional displacement measuring device, method and medium | |
| CN216792691U (en) | Three-dimensional displacement measuring device for holographic range of scattered light field | |
| TW201835549A (en) | Method and apparatus for digital holographic microtomography | |
| JP2022162306A (en) | Surface shape measurement device and surface shape measurement method |
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 |