CN116840162A - 3D spectrum confocal sensor and detection equipment thereof - Google Patents
3D spectrum confocal sensor and detection equipment thereof Download PDFInfo
- Publication number
- CN116840162A CN116840162A CN202310663231.XA CN202310663231A CN116840162A CN 116840162 A CN116840162 A CN 116840162A CN 202310663231 A CN202310663231 A CN 202310663231A CN 116840162 A CN116840162 A CN 116840162A
- Authority
- CN
- China
- Prior art keywords
- lens group
- scanning
- light beam
- lens
- galvanometer
- 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
- 238000001228 spectrum Methods 0.000 title claims abstract description 53
- 238000001514 detection method Methods 0.000 title claims abstract description 26
- 238000003384 imaging method Methods 0.000 claims abstract description 48
- 239000013307 optical fiber Substances 0.000 claims abstract description 37
- 239000006185 dispersion Substances 0.000 claims abstract description 15
- 230000005540 biological transmission Effects 0.000 claims abstract description 9
- 230000003595 spectral effect Effects 0.000 claims description 45
- 230000003287 optical effect Effects 0.000 claims description 10
- 230000001678 irradiating effect Effects 0.000 claims description 5
- 230000004075 alteration Effects 0.000 claims description 3
- 229910052736 halogen Inorganic materials 0.000 claims description 3
- 150000002367 halogens Chemical class 0.000 claims description 3
- 239000000463 material Substances 0.000 claims description 3
- 229910052724 xenon Inorganic materials 0.000 claims description 3
- FHNFHKCVQCLJFQ-UHFFFAOYSA-N xenon atom Chemical compound [Xe] FHNFHKCVQCLJFQ-UHFFFAOYSA-N 0.000 claims description 3
- 230000007704 transition Effects 0.000 abstract description 3
- 239000000523 sample Substances 0.000 description 44
- 230000008859 change Effects 0.000 description 5
- 230000007547 defect Effects 0.000 description 5
- 239000000835 fiber Substances 0.000 description 5
- 230000001360 synchronised effect Effects 0.000 description 4
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 3
- 238000013461 design Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 229910052744 lithium Inorganic materials 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000004611 spectroscopical analysis Methods 0.000 description 2
- 238000005253 cladding Methods 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000011038 discontinuous diafiltration by volume reduction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/255—Details, e.g. use of specially adapted sources, lighting or optical systems
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/01—Arrangements or apparatus for facilitating the optical investigation
Abstract
The invention discloses a 3D spectrum confocal sensor and detection equipment, wherein the sensor comprises: the device comprises a wide-spectrum light source, an optical fiber coupler, a first lens group, a scanning galvanometer, a second lens group, a third lens group, a dispersion element, a fourth lens group, a fifth lens group, a scanning lens, a sixth lens group and an area array camera, wherein the third lens group, the dispersion element, the fourth lens group, the fifth lens group, the scanning lens, the sixth lens group and the area array camera are sequentially arranged along the transmission path of an imaging light beam; the area array camera is positioned on the image space focal plane of the sixth lens group; the controller is used for controlling the scanning galvanometer and the scanning frequency of the scanning galvanometer to be the same as the exposure frequency of the area array camera; the scanning mirror changes a scanning angle, and the scanning beam of the area array camera is converted into the scanning beam of the next adjacent column of pixels. The transition from point scanning to line scanning is realized, the imaging speed is high, and the imaging quality is high.
Description
Technical Field
The invention relates to the technical field of optics, in particular to a 3D spectrum confocal sensor and detection equipment thereof.
Background
Currently, spectral confocal sensors are widely used in optical detection in various industries, wherein the spectral confocal sensors are generally classified into point spectral confocal sensors and line spectral confocal sensors. The point spectrum confocal sensor has the defects that the point spectrum confocal sensor collects spectrum data by using a linear array camera, and each line of data of the linear array camera can collect one line of spectrum data; because the current linear array camera is limited by the technology of a linear array image sensing chip, in addition, the linear array camera uses fewer digital-to-analog conversion (ADC) channels, the data acquisition rate of the current linear array camera is lower, and the line frequency is limited to hundreds of thousands of lines/second, so that the imaging speed of the current point-spectrum confocal sensor is also limited to hundreds of thousands of lines/second. The conventional line spectrum confocal sensor has the defects that the line spectrum confocal sensor illuminates one line of a sample to be detected, reflected light of the line is led into a spectrometer in parallel through free space, and parallel spectrum acquisition is carried out on the reflected light of the line. Because the optical and mechanical structures in free space are needed, the optical fiber transmission mode cannot be adopted, and the spectrometer and the probe are required to be fixedly installed together, so that the optical fiber probe is large in size and weight, and is not suitable for detecting scenes in compact space and scenes needing mobile measurement.
Disclosure of Invention
The invention provides a 3D spectrum confocal sensor and detection equipment thereof, which are convenient to install and use on the basis of improving imaging speed and imaging quality because an imaging light path in the detection probe and the 3D spectrum confocal sensor is connected by an optical fiber.
To achieve the above object, an embodiment of an aspect of the present invention provides a 3D spectral confocal sensor, including:
the device comprises a wide-spectrum light source, an optical fiber coupler, a first lens group, a scanning galvanometer, a second lens group, a third lens group, a dispersion element, a fourth lens group, a fifth lens group, a scanning lens, a sixth lens group and an area array camera, wherein the third lens group, the dispersion element, the fourth lens group, the fifth lens group, the scanning lens, the sixth lens group and the area array camera are sequentially arranged along the transmission path of an imaging light beam;
the wide spectrum light source emits a wide spectrum light beam to a light source input end of the optical fiber coupler, the wide spectrum light beam is output to the first lens group through the optical fiber coupler, the first lens group collimates the wide spectrum light beam to form a first collimated light beam to the scanning vibrating mirror, the scanning vibrating mirror scans the first collimated light beam to the second lens group, the second lens group is used for separating the first collimated light beam into focused light beams with different wavelengths along an axis and irradiating the focused light beams onto a sample to be detected, and the focused light beams with corresponding wavelengths reflected at different depth positions of the sample to be detected sequentially pass through the second lens group, the scanning vibrating mirror, the first lens group and the optical fiber coupler and then are incident to the third lens group to form imaging light beams;
the third lens group is used for receiving an imaging light beam and collimating the imaging light beam to form a second collimated light beam, the dispersive element is used for expanding the second collimated light beam to form a dispersed light beam, the fourth lens group is used for focusing the dispersed light beam to form a second focusing light beam, the fifth lens group is used for collimating the second focusing light beam to form a third collimated light beam, the scanning mirror is used for scanning the third collimated light beam to form a scanning light beam, the sixth lens group is used for focusing the scanning light beam to the area array camera, and the area array camera is positioned on an image side focal plane of the sixth lens group;
the controller is respectively and electrically connected with the scanning galvanometer, the scanning mirror and the area array camera and is used for controlling the scanning frequency of the scanning galvanometer and the scanning mirror to be the same as the exposure frequency of the area array camera; the scanning mirror changes a scanning angle, and the scanning light beam sampled by the last column of pixels of the area array camera is converted into the scanning light beam sampled by the next column of pixels adjacent to the last column of pixels.
Optionally, the second lens group is a lens group that enlarges chromatic aberration in an axial direction.
Optionally, the dispersive element is located at an object-side focal plane of the fourth lens group, the image-side focal plane of the fourth lens group is located at the same position as the object-side focal plane of the fifth lens group, and the scanning mirror is located at the image-side focal plane of the fifth lens group, or the scanning mirror is located at the image-side focal plane of the fifth lens group and is also located at the object-side focal plane of the sixth lens group.
Optionally, the third lens group comprises at least one lens; the fourth lens group includes at least one lens; the fifth lens group comprises at least one lens; the sixth lens group includes at least one lens.
Optionally, the third lens group is a reflective lens group or a transmissive lens group, the fourth lens group is a reflective lens group or a transmissive lens group, the fifth lens group is a reflective lens group or a transmissive lens group, and the sixth lens group is a reflective lens group or a transmissive lens group.
Optionally, the scanning mirror is one of a galvanometer scanning galvanometer, a resonance galvanometer, a MEMS galvanometer, a polygon turning mirror, an electro-optic deflector or an acousto-optic deflector.
Optionally, the scanning galvanometer is one of a galvanometer scanning galvanometer, a resonance galvanometer and an MEMS galvanometer.
Optionally, the dispersion element is one of a grating, a prism, a diffraction beam splitter or a super surface material optical beam splitter, and the dispersion element is a reflective dispersion element or a transmissive dispersion element.
Optionally, the broad spectrum light source is one of a white light LED, a halogen lamp, a xenon lamp, or a laser driven white light source.
To achieve the above object, another embodiment of the present invention provides a detection device, including a 3D spectral confocal sensor according to any embodiment of the present invention.
According to the 3D spectrum confocal sensor and the detection device provided by the embodiment of the invention, the 3D spectrum confocal sensor comprises: the device comprises a wide-spectrum light source, an optical fiber coupler, a first lens group, a scanning galvanometer, a second lens group, a third lens group, a dispersion element, a fourth lens group, a fifth lens group, a scanning lens, a sixth lens group and an area array camera, wherein the third lens group, the dispersion element, the fourth lens group, the fifth lens group, the scanning lens, the sixth lens group and the area array camera are sequentially arranged along the transmission path of an imaging light beam; the wide spectrum light source emits a wide spectrum light beam to a light source input end of the optical fiber coupler, the wide spectrum light beam is output to the first lens group through the optical fiber coupler, the first lens group collimates the wide spectrum light beam to form a first collimated light beam to the scanning vibrating mirror, the scanning vibrating mirror scans the first collimated light beam to the second lens group, the second lens group is used for separating the first collimated light beam into focused light beams with different wavelengths along an axis and irradiating the focused light beams onto a sample to be detected, and the focused light beams with corresponding wavelengths reflected at different depth positions of the sample to be detected sequentially pass through the second lens group, the scanning vibrating mirror, the first lens group and the optical fiber coupler and then are incident to the third lens group to form imaging light beams; the third lens group is used for receiving the imaging light beam and collimating the imaging light beam to form a second collimated light beam, the dispersive element is used for expanding the second collimated light beam to form a dispersed light beam, the fourth lens group is used for focusing the dispersed light beam to form a second focusing light beam, the fifth lens group is used for collimating the second focusing light beam to form a third collimated light beam, the scanning mirror is used for scanning the third collimated light beam to form a scanning light beam, the sixth lens group is used for focusing the scanning light beam to the area camera, and the area camera is positioned on the focal plane of the image side of the sixth lens group; the controller is respectively and electrically connected with the scanning galvanometer, the scanning mirror and the area array camera and is used for controlling the scanning frequency of the scanning galvanometer and the scanning mirror to be the same as the exposure frequency of the area array camera; the scanning mirror changes a scanning angle, and the scanning beam of the area array camera is converted into the scanning beam of the next adjacent column of pixels. Therefore, through the arrangement, the transition from point scanning to line scanning is realized through the arrangement of the scanning galvanometer, the imaging speed and the imaging quality are improved through the use of the area array camera, and the 3D spectrum confocal sensor is movably connected between an imaging light path and a detection light path through the use of the optical fiber coupler, so that the imaging light path is convenient to detach, assemble and carry.
It should be understood that the description in this section is not intended to identify key or critical features of the embodiments of the invention or to delineate the scope of the invention. Other features of the present invention will become apparent from the description that follows.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic diagram of an optical path of a 3D spectral confocal sensor according to an embodiment of the present invention;
fig. 2 is a schematic diagram of a process of capturing an imaging beam by an area camera in a 3D spectral confocal sensor according to an embodiment of the invention.
Detailed Description
In order that those skilled in the art will better understand the present invention, a technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in which it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present invention without making any inventive effort, shall fall within the scope of the present invention.
It should be noted that the terms "first," "second," and the like in the description and the claims of the present invention and the above figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that the embodiments of the invention described herein may be implemented in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprise" and "have," as well as any variations thereof, are intended to cover a non-exclusive inclusion.
Fig. 1 is a schematic diagram of an optical path of a 3D spectral confocal sensor according to an embodiment of the present invention. As shown in fig. 1, the 3D spectral confocal sensor 100 includes:
a wide-spectrum light source 101, an optical fiber coupler 102, a first lens group 103, a scanning galvanometer 104, a second lens group 105, a third lens group 106, a dispersive element 107, a fourth lens group 108, a fifth lens group 109, a scanning mirror 110, a sixth lens group 111 and an area camera 112, which are sequentially arranged along the imaging beam transmission path, a controller 113;
the wide-spectrum light source 101 emits a wide-spectrum light beam to a light source input end of the optical fiber coupler 102, the wide-spectrum light beam is output to the first lens group 103 through the optical fiber coupler 102, the first lens group 103 collimates the wide-spectrum light beam to form a first collimated light beam to the scanning galvanometer 104, the scanning galvanometer 104 scans the first collimated light beam to the second lens group 105, the second lens group 105 is used for separating the first collimated light beam into focused light beams with different wavelengths along an axis and irradiating the focused light beams onto the sample 200 to be detected, and the focused light beams with corresponding wavelengths reflected at different depth positions of the sample 200 to be detected sequentially pass through the second lens group 105, the scanning galvanometer 104, the first lens group 103 and the optical fiber coupler 102 and then are incident to the third lens group 106 to form imaging light beams;
the third lens group 106 is used for receiving the imaging light beam and collimating the imaging light beam to form a second collimated light beam, the dispersive element 107 is used for expanding the second collimated light beam to form a dispersed light beam, the fourth lens group 108 is used for focusing the dispersed light beam to form a second focusing light beam, the fifth lens group 109 is used for collimating the second focusing light beam to form a third collimated light beam, the scanning mirror 110 is used for scanning the third collimated light beam to form a scanning light beam, the sixth lens group 111 is used for focusing the scanning light beam to the area array camera 112, and the area array camera 112 is positioned on the image side focal plane of the sixth lens group 111;
the controller 113 is electrically connected to the scanning galvanometer 104, the scanning mirror 110, and the area camera 112, and is used for controlling the scanning frequency of the scanning galvanometer 104 and the scanning mirror 110 to be the same as the exposure frequency of the area camera 112; the scanning mirror 110 changes a scanning angle and the scanning beam of the area camera 112 is converted from the last column of pixel sample scanning beams to the next adjacent column of pixel sample scanning beams.
It can be understood that the broad spectrum light beam emitted by the broad spectrum light source 101 is led into the optical fiber coupler 102, and is emitted from the end face of one optical fiber of the optical fiber coupler 102 to form a sample light beam, and is incident on the first lens group 103, and the first lens group 103 collimates the light beam into a parallel light beam (i.e. forms a first collimated light beam); the parallel beam (first collimated beam) enters a scanning galvanometer mirror 104 (alternatively, the scanning galvanometer mirror may be a resonant mirror, or MEMS mirror, etc.), and is then focused by a second lens set 105 onto the sample 200 to be measured; the second lens group 105 (may be a dispersive lens) is capable of focusing light of different wavelengths at different depth positions, and as shown in fig. 1, the focal points of the light of different wavelengths are distributed at different depth positions. Because of the conjugate relationship between the focal point of each wavelength of light and the end face of the optical fiber before the first lens group 103, the confocal detection effect can be achieved because the core diameter of the optical fiber is small. The surface of the sample 200 to be measured can only reflect light of a wavelength whose focal point is located exactly at the depth of the surface of the sample 200 to be measured back to the optical fiber. The light with other wavelengths is in an out-of-focus state because the depth position of the focal point is higher or lower than the surface of the sample 200 to be measured, and the light spot returned to the end face of the optical fiber is very large and can be shielded by the cladding structure of the optical fiber, so that the light cannot effectively enter the fiber core of the optical fiber coupler 102. If the sample 200 to be measured is a transparent multilayer structure, such as a multiple layer glass, due to the multiple layer surface, light of multiple wavelengths can be reflected by multiple surfaces of the sample to be measured and returned into the fiber coupler 102.
The scanning galvanometer 104 may be an x-y scanning galvanometer, i.e., a focused sample beam scans the sample in the x and y directions as it is deflected in the x and y directions, allowing for lateral scanning of the sample.
Therefore, by setting the scanning galvanometer 104, a point light source formed by a wide spectrum light beam is focused on the sample 200 to be detected, and is scanned on the sample 200 to be detected, and on the basis of realizing the function of the line spectrum confocal sensor 100, the light beam can be transmitted through an optical fiber.
The sample beam reflected by the sample 200 to be measured is returned to the fiber coupler, guided out from the other fiber in the fiber coupler, formed into an imaging beam, collimated into a parallel beam (second collimated beam) by the third lens group 106, and then irradiated onto the dispersive element 107. The dispersive element 107 spreads the beam dispersions of the different wavelengths in the parallel beams into different directions.
The light beams of different wavelengths dispersed and spread by the dispersive element 107 are incident on the fourth lens group 108, and the dispersive element 107 is located at the object focal plane of the fourth lens group 108. The fourth lens group 108 focuses parallel light beams with different wavelengths at the focal plane of the image side of the fourth lens group 108, each wavelength of light is focused by the fourth lens group 108 into a point, and a plurality of wavelengths of light are focused by the fourth lens group 108 into an intermediate spectral line. The fourth lens group 108 may be transmissive or reflective, and the fourth lens group 108 includes at least one lens.
The intermediate spectral lines then diverge and are incident on the fifth lens group 109. The object-side focal plane of the fifth lens group 109 and the image-side focal plane of the fourth lens group 108 coincide. Thus, the fifth lens group 109 collimates light of each wavelength into a parallel beam (third collimated beam); however, these parallel light beams with different wavelengths are converged and overlapped at the focal plane of the image side of the fifth lens group 109. The fifth lens group 109 can be transmissive or reflective, and the fifth lens group 109 can include at least one lens.
At the image side focal plane of the fifth lens group 109, a scanning mirror 110 is disposed, and the scanning mirror 110 may be a galvanometer scanning mirror (for example, a galvanometer scanning mirror, a resonant mirror, or a MEMS mirror, etc.), a rotating polygon mirror, an electro-optical deflector, or an acousto-optical deflector, etc. The parallel light beams with different wavelengths are converged and overlapped with each other, and then dispersed after being reflected by the scanning mirror 110 (i.e. at the image focal plane of the fifth lens group 109). Continuing to enter the sixth lens group 111, the sixth lens group 111 focuses the parallel light beams with different wavelengths at the focal plane of the image side of the sixth lens group 111 to form a spectral line. The sixth lens group 111 may be transmissive or reflective, and the sixth lens group 111 includes at least one lens.
An area camera 112 is used to receive the spectral line, and an area image sensor chip in the area camera 112 is located at the focal plane of the image side of the sixth lens group 111, so that a clear spectral line can be obtained, and a spectral line can be received by an in-line pixel of the area camera 112. The area camera 112 includes an area image sensor (which may be a CCD, CMOS, NMOS, or other type of area image sensor).
The scanning period of the scanning mirror 110 and the exposure period of the area camera 112 are synchronized using an electric signal. When the scanning mirror 110 scans the light beam, the spectral lines are scanned and moved on the area array image sensor, so that the spectral lines sequentially irradiate pixels of different lines of the area array image sensor at different times in one scanning period of the scanning mirror 110. Thus, the planar array image sensor is scanned line by line during one scanning period of the scanning mirror 110, and a spectrum of a plurality of lines at different times can be obtained.
It should be noted that the imaging light beams change according to the different points to be measured of the sample 200 to be measured, and for example, if there are two points to be measured, the imaging light beams correspondingly include a first imaging light beam and a second imaging light beam. As shown in fig. 2, the area camera 112 includes photosensitive elements 1121 arranged along rows and columns, and the first imaging beam sequentially passes through the third lens group 106, the dispersive element 107, the fourth lens group 108 and the fifth lens group 109, then strikes the scanning mirror 110, is scanned by the scanning mirror 110, and is focused onto a row of pixels on the area camera 112 by passing through the sixth lens group 111 (as in fig. 2, the first scanning beam 0061 is focused onto the photosensitive element 1121 corresponding to the row of pixels). After the imaging light beam sampled in the current period changes, the second imaging light beam sequentially passes through the third lens group 106, the dispersive element 107, the fourth lens group 108 and the fifth lens group 109, and then strikes the scanning mirror 110, is scanned by the scanning mirror 110, and is focused onto one row of pixels on the area camera 112 through the sixth lens group 111 (as in fig. 2, the second scanning light beam 0062 is focused onto the photosensitive element 1121 corresponding to the other row of pixels), and the moving direction is shown in the x' direction in fig. 2. Further, as the point to be measured of the sample 200 is expected to change before the spectral confocal sensor, the scanning beam for each sample may be on the photosensitive element 1121 corresponding to one row of pixels of the area camera 112 by scanning the scanning mirror 110 in the imaging optical path. Thus, the imaging speed is greatly improved relative to a linear camera. In this embodiment, the size of the photosensitive elements 1121 in the x 'direction is larger than the width of the spectral line itself, and the size of the plurality of photosensitive elements 1121 in the direction perpendicular to the x' direction (i.e., the column direction in fig. 2) is larger than the length of the spectral line itself. The scan mirror 112 changes an angle such that the reflected spectral line moves from the last column of pixels to the next column of pixels. Wherein the scanning period of the scanning mirror 110 is synchronized with the exposure period of the area camera 112.
That is, when the third collimated beam reaches the scan mirror 110, the single wavelength beam is collimated, but the different wavelengths are converging. Upon exiting the scan mirror 110, the single wavelength beam is collimated, but is dispersed between different wavelengths. And then focused by the sixth lens group 111 into a thin spectral line (focused on a column of pixels of the area camera 112).
Spectral data acquired by the area camera 112 is transferred to a processor or computer (controller 113). Since each line of spectral data corresponds to a particular depth, for opaque samples, there is only one wavelength peak per line of spectral data, which corresponds to the depth at that point of the sample 200 to be measured. If the sample 200 to be measured is a transparent multilayer structure (such as a multiple layer glass, etc.), the spectrum data will have a plurality of wavelength peaks, each wavelength corresponding to the depth of the surface of each layer. The depth coordinate of the z direction of the sample 200 to be measured can be obtained by corresponding the wavelength of the wavelength peak of the spectrum data to the depth coordinate of the sample 200 to be measured (the relationship between the wavelength and the depth can be determined by calibration). If the scanning period of the xy scanning mirror for scanning the sample 200 in the x direction is synchronized with the scanning period of the scanning mirror 110 for scanning the spectrum, the exposure period of the area camera 112 is synchronized, and then the contour line of the sample 200 in the xz direction can be obtained after the above data processing is performed on each frame of spectrum data obtained by the area camera 112. If the scanning in the y direction of the sample 200 to be tested in the xy scanning galvanometer 104 is added; or the sample 200 to be measured is moved in the y direction to realize the scanning in the y direction, and the two methods can reconstruct and obtain the 3D contour map of the sample in three dimensions of x, z and y.
Alternatively, the second lens group 105 may be a lens group that expands chromatic aberration in an axial direction. I.e. the multispectral light source passes through the second lens group 105 (which may be a chromatic lens), and then light with different wavelengths is separated from the multispectral light source along different depths in the axial direction.
Optionally, the dispersive element 107 is located at the object focal plane of the fourth lens group 106, the image Fang Jiaomian of the fourth lens group 108 is co-located with the object focal plane of the fifth lens group 109, the scanning mirror 110 is located at the image focal plane of the fifth lens group 109, or the scanning mirror is located at the image focal plane of the fifth lens group and also at the object focal plane of the sixth lens group.
The dispersive element 107 is located at the object focal plane of the fourth lens group 108, and the image Fang Jiaomian of the fourth lens group 108 and the object focal plane of the fifth lens group 109 are located at the same position, so that the dispersed light beam is focused into a spectral line after the fourth lens group 108. The scanning mirror 110 is located at the focal plane of the image side of the fifth lens group 109, so that when the third collimated light beam reaches the scanning mirror 110, the light beams with different wavelengths are in a converging state, and after being scanned by the scanning mirror 110, the scanning light beam can be collimated to reach the sixth lens group 111 and finally focused on the area array camera 112, so that in the light beam transmission process, imaging definition is improved, and spectra with different wavelengths can be resolved clearly. If the scanning mirror 110 is located at the object focal plane of the sixth lens group 109, an effect similar to that of an image telecentric lens is achieved, and the scanning beam is focused by the sixth lens group 109 and then vertically enters the pixel plane, so that the brightness of the image is improved.
Optionally, the third lens group 106 includes at least one lens; the fourth lens group 108 includes at least one lens; the fifth lens group 109 includes at least one lens; the sixth lens group 111 includes at least one lens. The lens may be a convex lens. The lens can also be a cemented lens cemented by different lenses, and can meet focusing and collimation functions, and the invention is not particularly limited to the above. The third lens group 106 is a collimating lens group, the fourth lens group 108 is a focusing lens group, the fifth lens group 109 is a collimating lens group, and the sixth lens group 111 is a focusing lens group.
Optionally, the third lens group 106 is a reflective lens group or a transmissive lens group, the fourth lens group 108 is a reflective lens group or a transmissive lens group, the fifth lens group 109 is a reflective lens group or a transmissive lens group, and the sixth lens group 111 is a reflective lens group or a transmissive lens group.
Wherein, by reasonably configuring the reflected or transmitted light beams of the third lens group 106, the fourth lens group 108, the fifth lens group 109 and the sixth lens group 111, the design of the light path change is facilitated, such as the reduction of the volume of the whole light path is facilitated.
With continued reference to fig. 1, in fig. 1, the third lens group 106, the fourth lens group 108, the fifth lens group 109, and the sixth lens group 111 are all transmissive lenses. If the optical path is required to be folded back, one or more of the lens groups can be arranged as a reflective lens, and the reflective surface of the lens group can be coated with a reflective coating to realize reflection. Alternatively, a mirror is provided in the optical path to change the path direction.
Alternatively, the scanning mirror 110 is one of a galvanometer scanning galvanometer, a resonant galvanometer, a MEMS galvanometer, a polygon mirror, an electro-optic deflector, or an acousto-optic deflector.
Optionally, the dispersive element 107 is one of a grating, a prism, a diffraction spectroscopy device, or a super surface material optical spectroscopy device, and the dispersive element 107 is a reflective dispersive element or a transmissive dispersive element. The design of the light path change is facilitated, for example, the volume reduction of the whole light path is facilitated.
Alternatively, the broad spectrum light source 101 is one of a white LED, a halogen lamp, a xenon lamp, or a laser-driven white light source.
The embodiment of the invention also provides a detection device, which comprises the 3D spectrum confocal sensor 100 according to any embodiment of the invention.
The 3D spectral confocal sensor 100 for collecting spectral data uses the scanning mirror 110 to scan the spectral line on the area array camera 112, and has higher data acquisition rate due to the greater digital-to-analog conversion (ADC) channel number of the area array camera 112 than the linear array camera, so that the imaging speed of the spectral confocal sensor can be significantly improved. In addition, compared with a linear spectrum confocal sensor, the embodiment can adopt an optical fiber flexible connection probe (a detection part) and a spectrometer (an imaging part), and the probe is convenient to move and measure a sample due to the small volume and the small weight, and only the probe needs to be moved without moving together with the imaging part.
The 3D spectral confocal sensor can be applied in the field of industrial detection, including but not limited to: and 3C electronic product defect detection and precision measurement, such as shell detection of a mobile phone, curved surface screen detection, detection of a mobile phone lens, detection of a printed circuit board and the like. And (3) detection of a lithium battery: such as the detection of burrs on the pole pieces of a lithium battery and the detection of weld defects on the lithium battery casing. And (3) detection of a semiconductor: such as defect detection of chip packages, etc. And (3) detecting automobile parts: such as inspection of polished metal parts, etc.
In summary, according to the 3D spectral confocal sensor and the detection device provided by the embodiments of the present invention, the 3D spectral confocal sensor includes: the device comprises a wide-spectrum light source, an optical fiber coupler, a first lens group, a scanning galvanometer, a second lens group, a third lens group, a dispersion element, a fourth lens group, a fifth lens group, a scanning lens, a sixth lens group and an area array camera, wherein the third lens group, the dispersion element, the fourth lens group, the fifth lens group, the scanning lens, the sixth lens group and the area array camera are sequentially arranged along the transmission path of an imaging light beam; the wide spectrum light source emits a wide spectrum light beam to a light source input end of the optical fiber coupler, the wide spectrum light beam is output to the first lens group through the optical fiber coupler, the first lens group collimates the wide spectrum light beam to form a first collimated light beam to the scanning vibrating mirror, the scanning vibrating mirror scans the first collimated light beam to the second lens group, the second lens group is used for separating the first collimated light beam into focused light beams with different wavelengths along an axis and irradiating the focused light beams onto a sample to be detected, and the focused light beams with corresponding wavelengths reflected at different depth positions of the sample to be detected sequentially pass through the second lens group, the scanning vibrating mirror, the first lens group and the optical fiber coupler and then are incident to the third lens group to form imaging light beams; the third lens group is used for receiving the imaging light beam and collimating the imaging light beam to form a second collimated light beam, the dispersive element is used for expanding the second collimated light beam to form a dispersed light beam, the fourth lens group is used for focusing the dispersed light beam to form a second focusing light beam, the fifth lens group is used for collimating the second focusing light beam to form a third collimated light beam, the scanning mirror is used for scanning the third collimated light beam to form a scanning light beam, the sixth lens group is used for focusing the scanning light beam to the area camera, and the area camera is positioned on the focal plane of the image side of the sixth lens group; the controller is respectively and electrically connected with the scanning galvanometer, the scanning mirror and the area array camera and is used for controlling the scanning frequency of the scanning galvanometer and the scanning mirror to be the same as the exposure frequency of the area array camera; the scanning mirror changes a scanning angle, and the scanning beam of the area array camera is converted into the scanning beam of the next adjacent column of pixels. Therefore, through the arrangement, the transition from point scanning to line scanning is realized through the arrangement of the scanning galvanometer, the imaging speed and the imaging quality are improved through the use of the area array camera, and the spectral confocal sensor adopts optical fiber transmission light sources.
The above embodiments do not limit the scope of the present invention. It will be apparent to those skilled in the art that various modifications, combinations, sub-combinations and alternatives are possible, depending on design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of the present invention.
Claims (10)
1. A 3D spectral confocal sensor, comprising:
the device comprises a wide-spectrum light source, an optical fiber coupler, a first lens group, a scanning galvanometer, a second lens group, a third lens group, a dispersion element, a fourth lens group, a fifth lens group, a scanning lens, a sixth lens group and an area array camera, wherein the third lens group, the dispersion element, the fourth lens group, the fifth lens group, the scanning lens, the sixth lens group and the area array camera are sequentially arranged along the transmission path of an imaging light beam;
the wide spectrum light source emits a wide spectrum light beam to a light source input end of the optical fiber coupler, the wide spectrum light beam is output to the first lens group through the optical fiber coupler, the first lens group collimates the wide spectrum light beam to form a first collimated light beam to the scanning vibrating mirror, the scanning vibrating mirror scans the first collimated light beam to the second lens group, the second lens group is used for separating the first collimated light beam into focused light beams with different wavelengths along an axis and irradiating the focused light beams onto a sample to be detected, and the focused light beams with corresponding wavelengths reflected at different depth positions of the sample to be detected sequentially pass through the second lens group, the scanning vibrating mirror, the first lens group and the optical fiber coupler and then are incident to the third lens group to form imaging light beams;
the third lens group is used for receiving an imaging light beam and collimating the imaging light beam to form a second collimated light beam, the dispersive element is used for expanding the second collimated light beam to form a dispersed light beam, the fourth lens group is used for focusing the dispersed light beam to form a second focusing light beam, the fifth lens group is used for collimating the second focusing light beam to form a third collimated light beam, the scanning mirror is used for scanning the third collimated light beam to form a scanning light beam, the sixth lens group is used for focusing the scanning light beam to the area array camera, and the area array camera is positioned on an image side focal plane of the sixth lens group;
the controller is respectively and electrically connected with the scanning galvanometer, the scanning mirror and the area array camera and is used for controlling the scanning frequency of the scanning galvanometer and the scanning mirror to be the same as the exposure frequency of the area array camera; the scanning mirror changes a scanning angle, and the scanning light beam sampled by the last column of pixels of the area array camera is converted into the scanning light beam sampled by the next column of pixels adjacent to the last column of pixels.
2. The 3D spectral confocal sensor of claim 1 wherein said second lens group is an axially enlarged chromatic aberration lens group.
3. The 3D spectral confocal sensor of claim 1 wherein the dispersive element is located at an object-side focal plane of the fourth lens group, the image-side focal plane of the fourth lens group is co-located with the object-side focal plane of the fifth lens group, the scanning mirror is located at an image-side focal plane of the fifth lens group, or the scanning mirror is located at an image-side focal plane of the fifth lens group, and is also located at an object-side focal plane of the sixth lens group.
4. The 3D spectral confocal sensor of claim 1 wherein said third lens group comprises at least one lens; the fourth lens group includes at least one lens; the fifth lens group comprises at least one lens; the sixth lens group includes at least one lens.
5. The 3D spectral confocal sensor of claim 1 wherein the third lens group is a reflective or transmissive lens group, the fourth lens group is a reflective or transmissive lens group, the fifth lens group is a reflective or transmissive lens group, and the sixth lens group is a reflective or transmissive lens group.
6. The 3D spectral confocal sensor of claim 1 wherein the scanning mirror is one of a galvanometer scanning galvanometer, a resonant galvanometer, a MEMS galvanometer, a polygonal turning mirror, an electro-optic deflector, or an acousto-optic deflector.
7. The 3D spectral confocal sensor of claim 1 wherein said scanning galvanometer, resonant galvanometer, MEMS galvanometer.
8. The 3D spectral confocal sensor of claim 1 wherein the dispersive element is one of a grating, a prism, a diffractive beam splitter, or a super-surface material optical beam splitter, and the dispersive element is a reflective dispersive element or a transmissive dispersive element.
9. The 3D spectral confocal sensor of claim 1 wherein said broad spectrum light source is one of a white LED, a halogen lamp, a xenon lamp, or a laser-driven white light source.
10. A detection apparatus comprising a 3D spectral confocal sensor according to any of claims 1-9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310663231.XA CN116840162A (en) | 2023-06-06 | 2023-06-06 | 3D spectrum confocal sensor and detection equipment thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310663231.XA CN116840162A (en) | 2023-06-06 | 2023-06-06 | 3D spectrum confocal sensor and detection equipment thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116840162A true CN116840162A (en) | 2023-10-03 |
Family
ID=88158484
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310663231.XA Pending CN116840162A (en) | 2023-06-06 | 2023-06-06 | 3D spectrum confocal sensor and detection equipment thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116840162A (en) |
-
2023
- 2023-06-06 CN CN202310663231.XA patent/CN116840162A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| TWI414817B (en) | Linear chromatic confocal microscope system | |
| US9546962B2 (en) | Multi-spot scanning collection optics | |
| CN109073369B (en) | Confocal chromatic aberration apparatus and method for 2D/3D detection of objects such as wafers with variable spatial resolution | |
| US7369225B2 (en) | Device and method for inspecting surfaces in the interior of holes | |
| US7053395B2 (en) | Wafer defect detection system with traveling lens multi-beam scanner | |
| US8081309B2 (en) | Optical microscope and spectrum measuring method | |
| US8310669B2 (en) | Spectroscopic imaging method and system for exploring the surface of a sample | |
| US8928892B2 (en) | Wavefront analysis inspection apparatus and method | |
| WO2017162456A1 (en) | Method for 2d/3d inspection of an object such as a wafer | |
| US8614415B2 (en) | Defect inspection method of fine structure object and defect inspection apparatus | |
| WO2012029286A1 (en) | Spectrometry device and spectrometry method | |
| JP7232895B2 (en) | Chromatic confocal area sensor | |
| CN114047203B (en) | Spectrum confocal-based internal coaxial type automatic focusing device, method and system | |
| CN113137931B (en) | Spectrum confocal device and method capable of measuring surface shape or thickness | |
| US11782088B2 (en) | Devices, methods and sample holder for testing photonic integrated circuits and photonic integrated circuits | |
| EP2828700A1 (en) | Multi-color confocal microscope and imaging methods | |
| CN216898783U (en) | Confocal micro-measuring apparatu of line scanning spectrum | |
| CN116840162A (en) | 3D spectrum confocal sensor and detection equipment thereof | |
| US6172785B1 (en) | Light-scanning device | |
| CN116678310A (en) | Light-splitting interferometer and imaging light path thereof | |
| CN113959363A (en) | Line scanning type spectrum confocal device based on high-dispersion cylindrical lens and cylindrical concave grating | |
| CN115979165A (en) | Color confocal measurement system based on multi-point spectrum detection | |
| CN114720393A (en) | Lattice push-broom spectrum confocal device | |
| JP2000136982A (en) | Method and device for inspecting array element | |
| CN109596063A (en) | Multi-wavelength high resolution stereo vision measuring apparatus and method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination |