CN103791853A - Microstructure measuring device and measuring method based on color strip information processing - Google Patents
Microstructure measuring device and measuring method based on color strip information processing Download PDFInfo
- Publication number
- CN103791853A CN103791853A CN201410027013.8A CN201410027013A CN103791853A CN 103791853 A CN103791853 A CN 103791853A CN 201410027013 A CN201410027013 A CN 201410027013A CN 103791853 A CN103791853 A CN 103791853A
- Authority
- CN
- China
- Prior art keywords
- path difference
- optical path
- optical microscope
- color camera
- information
- 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
- 238000000034 method Methods 0.000 title claims abstract description 28
- 230000010365 information processing Effects 0.000 title claims abstract description 14
- 230000003287 optical effect Effects 0.000 claims abstract description 58
- 230000009466 transformation Effects 0.000 claims abstract description 12
- 229910052736 halogen Inorganic materials 0.000 claims abstract description 8
- 150000002367 halogens Chemical class 0.000 claims abstract description 8
- 230000007246 mechanism Effects 0.000 claims abstract description 7
- 238000012876 topography Methods 0.000 claims abstract description 5
- 238000012545 processing Methods 0.000 claims description 7
- 238000011156 evaluation Methods 0.000 claims description 6
- 230000001427 coherent effect Effects 0.000 claims description 5
- 238000005070 sampling Methods 0.000 claims description 5
- 238000002474 experimental method Methods 0.000 claims description 3
- 230000005540 biological transmission Effects 0.000 claims 1
- 238000005259 measurement Methods 0.000 abstract description 17
- 238000000691 measurement method Methods 0.000 abstract description 7
- 230000007613 environmental effect Effects 0.000 abstract description 3
- 238000010586 diagram Methods 0.000 description 8
- 230000008569 process Effects 0.000 description 6
- 238000013519 translation Methods 0.000 description 6
- 230000008859 change Effects 0.000 description 5
- 238000012360 testing method Methods 0.000 description 4
- 239000003990 capacitor Substances 0.000 description 3
- 230000003595 spectral effect Effects 0.000 description 3
- 238000002834 transmittance Methods 0.000 description 3
- 238000004458 analytical method Methods 0.000 description 2
- 238000006073 displacement reaction Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000001228 spectrum Methods 0.000 description 2
- 230000002238 attenuated effect Effects 0.000 description 1
- 239000001110 calcium chloride Substances 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 238000005286 illumination Methods 0.000 description 1
- 238000005305 interferometry Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
Images
Landscapes
- Length Measuring Devices By Optical Means (AREA)
Abstract
一种基于彩色条纹信息处理的微结构测量系统及测量方法,系统有Zeiss光学显微镜,输入光源卤素灯,Zeiss光学显微镜的样品扫描端设置有与计算机相连的扫描机构,Zeiss光学显微镜的信号采集端依次设置有CCD彩色相机和与CCD彩色相机相连的图像采集卡,所述的图像采集卡还连接计算机。方法:对CCD彩色相机采集的一组原始图像进行拜尔反变换;得到不同扫描位置处R、G、B的光强值;计算R、G、B通道的相位信息;确定零光程差的位置;得到像素点对应的高度信息;得到不同像素点对应的高度信息,最终得到物体的表面形貌。本发明使用CCD彩色相机采集白光干涉条纹图像,可以有效的减小环境噪声的影响,提高测量精度。
A microstructure measurement system and measurement method based on color fringe information processing. The system includes a Zeiss optical microscope, an input light source halogen lamp, a scanning mechanism connected to a computer at the sample scanning end of the Zeiss optical microscope, and a signal acquisition end of the Zeiss optical microscope. A CCD color camera and an image acquisition card connected with the CCD color camera are arranged in sequence, and the image acquisition card is also connected with a computer. Methods: Perform inverse Bayer transformation on a group of original images collected by a CCD color camera; obtain the light intensity values of R, G, and B at different scanning positions; calculate the phase information of the R, G, and B channels; determine the zero optical path difference position; obtain the height information corresponding to the pixel point; obtain the height information corresponding to different pixel points, and finally obtain the surface topography of the object. The invention uses a CCD color camera to collect white light interference fringe images, which can effectively reduce the influence of environmental noise and improve measurement accuracy.
Description
技术领域technical field
本发明涉及一种微结构测量系统。特别是涉及一种使用CCD彩色相机采集白光干涉条纹图像的基于彩色条纹信息处理的微结构测量系统及测量方法。The invention relates to a microstructure measurement system. In particular, it relates to a microstructure measurement system and measurement method based on color fringe information processing using a CCD color camera to collect white light interference fringe images.
背景技术Background technique
在微纳制造领域,微纳器件的表面形貌对系统的可靠性和质量影响显著。例如,MEMS电容器两平行极板的表面形貌会显著影响电容器的电容值、电压值、电场分布等机电特性,进而影响到MEMS电容器件的性能和成品率。此外,微纳器件的表面形貌可以反映出加工过程中的工艺参数,是对加工过程进行监控、诊断的重要依据。因而,微结构表面形貌的精密测量具有重要意义。In the field of micro-nano manufacturing, the surface morphology of micro-nano devices has a significant impact on the reliability and quality of the system. For example, the surface morphology of the two parallel plates of a MEMS capacitor will significantly affect the electromechanical properties of the capacitor, such as capacitance, voltage, and electric field distribution, which in turn will affect the performance and yield of MEMS capacitors. In addition, the surface morphology of micro-nano devices can reflect the process parameters in the processing process, which is an important basis for monitoring and diagnosing the processing process. Therefore, the precise measurement of microstructure surface topography is of great significance.
在微纳测试领域,白光干涉测量技术是一种重要的非接触式测量方法。在测试过程中,该技术不构成对被测物体表面的损伤,还具有测量范围大、测试精度高的优点。针对白光干涉信号处理的算法主要分为两种:一种是通过分析白光干涉信号的光强分布,获得被测物体的形貌,主要算法有重心法、多项式拟合法等;另一种是通过白光干涉信号的相位信息获取物体的形貌,主要算法有傅立叶变换法、小波变换法等。In the field of micro-nano testing, white light interferometry technology is an important non-contact measurement method. During the test process, this technology does not constitute damage to the surface of the measured object, and also has the advantages of large measurement range and high test accuracy. The algorithm for white light interference signal processing is mainly divided into two types: one is to obtain the shape of the measured object by analyzing the light intensity distribution of the white light interference signal, and the main algorithms include center of gravity method, polynomial fitting method, etc.; The phase information of the white light interference signal obtains the shape of the object, and the main algorithms include Fourier transform method, wavelet transform method, etc.
在采集白光干涉条纹的过程中,通常使用的是CCD黑白相机,而利用CCD彩色相机可使获取的图像信息由二维扩展为三维,即R、G、B三个通道的信息。E.等人利用3-CCD彩色相机获取白光干涉图像,但由于采集的干涉信号蓝色波段光谱能量较弱,所以只使用了R、G两个通道的信息分析得到被测物体的形貌;Suodong Ma等人基于加窗傅里叶变换的方法,通过对3-CCD彩色相机采集的R、G、B三个通道的图像进行分析,获得了被测物体的形貌;相较于通过棱镜分光实现彩色图像获取的3-CCD彩色相机,单CCD彩色相机通过拜尔(Bayer)滤波获取彩色图像的方法成本更为低廉,Zdeněk Buchta等人基于实验验证了使用单CCD彩色相机采集白光干涉图像,进而分析获得物体三维形貌的可行性。In the process of collecting white light interference fringes, CCD black-and-white cameras are usually used, and the use of CCD color cameras can expand the acquired image information from two-dimensional to three-dimensional, that is, the information of the three channels of R, G, and B. e. et al. used a 3-CCD color camera to obtain white light interference images, but because the collected interference signals have weak spectral energy in the blue band, they only used the information analysis of the R and G channels to obtain the shape of the measured object; Suodong Ma et al. based on the windowed Fourier transform method, by analyzing the images of the R, G, and B channels collected by the 3-CCD color camera, the morphology of the measured object was obtained; The 3-CCD color camera for color image acquisition, the method of acquiring color images with a single CCD color camera through Bayer (Bayer) filtering is cheaper, and Zdeněk Buchta et al. have verified based on experiments that a single CCD color camera is used to collect white light interference images, and then Analyze the feasibility of obtaining the three-dimensional shape of the object.
发明内容Contents of the invention
本发明所要解决的技术问题是,提供一种可以有效的减小环境噪声影响、提高测量精度的基于彩色条纹信息处理的微结构测量系统及测量方法。The technical problem to be solved by the present invention is to provide a microstructure measurement system and measurement method based on color fringe information processing that can effectively reduce the impact of environmental noise and improve measurement accuracy.
本发明所采用的技术方案是:一种基于彩色条纹信息处理的微结构测量系统,包括有Zeiss光学显微镜,Zeiss光学显微镜的光源输入端设置有卤素灯,Zeiss光学显微镜的样品扫描端设置有用于对样品进行垂直扫描,并与计算机相连的扫描机构,Zeiss光学显微镜的信号采集端依次设置有CCD彩色相机和与CCD彩色相机相连的图像采集卡,所述的图像采集卡还连接计算机。The technical solution adopted in the present invention is: a microstructure measurement system based on color fringe information processing, including a Zeiss optical microscope, the light source input end of the Zeiss optical microscope is provided with a halogen lamp, and the sample scanning end of the Zeiss optical microscope is provided with a The sample is scanned vertically, and the scanning mechanism connected to the computer, the signal acquisition end of the Zeiss optical microscope is sequentially provided with a CCD color camera and an image acquisition card connected to the CCD color camera, and the image acquisition card is also connected to the computer.
在所述的Zeiss光学显微镜与所述的卤素灯之间设置有用于降低蓝色波段以外波段的光透射率的白平衡滤光片。A white balance filter for reducing light transmittance in bands other than the blue band is arranged between the Zeiss optical microscope and the halogen lamp.
在所述的扫描机构包括有与所述的Zeiss光学显微镜的样品扫描端对应设置的物镜纳米定位器和与所述的物镜纳米定位器相连的压电控制器,所述的压电控制器通过RS232连接计算机,所述的物镜纳米定位器连接在Mirau型干涉物镜上,所述的Mirau型干涉物镜与设置在实验台上的样品相对应设置。The scanning mechanism includes an objective nanopositioner corresponding to the sample scanning end of the Zeiss optical microscope and a piezoelectric controller connected to the objective nanopositioner, and the piezoelectric controller passes through The RS232 is connected to the computer, and the objective lens nanopositioner is connected to the Mirau type interference objective lens, and the Mirau type interference objective lens is set correspondingly to the samples arranged on the experimental table.
本发明的用于基于彩色条纹信息处理的微结构测量系统的测量方法,包括如下步骤:The measuring method for the microstructure measuring system based on color fringe information processing of the present invention comprises the following steps:
1)对CCD彩色相机采集的一组原始图像进行拜尔反变换,得到真实的彩色图像信息;1) Perform inverse Bayer transformation on a group of original images collected by a CCD color camera to obtain real color image information;
2)分别提取由步骤1)变换得到的彩色图像任一像素点的R、G和B通道光强信息,进而得到不同扫描位置处R、G、B的光强值;2) Extract the R, G, and B channel light intensity information of any pixel of the color image transformed by step 1), and then obtain the light intensity values of R, G, and B at different scanning positions;
3)选择Morlet小波作为小波变换的母小波,对步骤2)得到的R、G、B通道的光强值做一维连续小波变换,利用变换结果计算R、G、B通道的相位信息;3) Select the Morlet wavelet as the mother wavelet of the wavelet transform, perform one-dimensional continuous wavelet transform on the light intensity values of the R, G, and B channels obtained in step 2), and use the transformation results to calculate the phase information of the R, G, and B channels;
4)对步骤3)得到的R、G、B通道的相位信息,基于构造的评价函数初步确定零光程差的位置;4) For the phase information of the R, G, and B channels obtained in step 3), based on the constructed evaluation function Preliminary determination of the position of zero optical path difference;
5)选取零光程差附近R、G、B通道的相位信息,对所述R、G、B通道的相位信息做最小二乘拟合得到零光程差位置最优估计值,即精确确定零光程差的位置;5) Select the phase information of the R, G, and B channels near zero optical path difference, and perform least squares fitting on the phase information of the R, G, and B channels to obtain the optimal estimated value of the zero optical path difference position, that is, accurately determine The position of zero optical path difference;
6)利用步骤5)得到的零光程差位置最优估计值,得到步骤2)所述像素点对应的高度信息;6) Using the optimal estimated value of the zero optical path difference position obtained in step 5), obtain the height information corresponding to the pixel in step 2);
7)对步骤1)变换得到的彩色图像的其它像素点分别作与步骤2)至步骤6)相同的处理,从而得到不同像素点对应的高度信息,最终得到物体的表面形貌。7) Perform the same processing as steps 2) to 6) on the other pixels of the color image transformed in step 1), so as to obtain the height information corresponding to different pixels, and finally obtain the surface topography of the object.
步骤2)所述的任一像素点的R、G和B的光强值是由下式得到:Step 2) The light intensity values of R, G and B at any pixel point are obtained by the following formula:
其中,m分别表示为R、G、B,代表CCD彩色相机的R、G、B通道;I0m表示背景光强;γm表示条纹可见度;λcm表示光源在对应通道的中心波长;z表示物镜纳米定位器垂直扫描的位置,当发生干涉的两光束光程差为零时,物镜纳米定位器所在的位置表示为z0,简称为零光程差位置;g(zm-z0)是相干包络项。Among them, m represents R, G, B respectively, representing the R, G, B channels of the CCD color camera; I 0m represents the background light intensity; γ m represents the visibility of stripes; λ cm represents the central wavelength of the light source in the corresponding channel; The vertical scanning position of the nanopositioner of the objective lens, when the optical path difference between the two beams that interfere is zero, the position of the nanopositioner of the objective lens is expressed as z 0 , referred to as the zero optical path difference position; g(z m -z 0 ) is the coherent envelope term.
所述的相干包络项表示为The coherent envelope term is expressed as
其中,lcm表示光源在对应通道的相干长度。Among them, l cm represents the coherence length of the light source in the corresponding channel.
步骤3)所述的R、G、B通道相位信息,是通过下述三步得到:The R, G, B channel phase information described in step 3) is obtained through the following three steps:
第一步,选择Morlet小波作为小波变换的母小波,即 In the first step, Morlet wavelet is selected as the mother wavelet of wavelet transform, namely
第二步,对Im(z)进行一维连续小波变换得到:In the second step, one-dimensional continuous wavelet transform is performed on I m (z) to obtain:
其中,ψ(z)为小波变换的母小波,a,b分别表示小波变换的尺度因子和平移因子,
第三步,R、G、B通道相位信息通过Wm(a,b)的辐角即The third step, R, G, B channel phase information Through the argument of W m (a,b) that is
得到,其中,a0,b0为Wm(a,b)的模值最大时对应的尺度因子和平移因子,Re[Wm(a0,b0)]和Im[Wm(a0,b0)]分别表示Wm(a0,b0)的实部和虚部。Obtained, where a 0 , b 0 is the scale factor and translation factor corresponding to the maximum modulus value of W m (a,b), Re[W m (a 0 ,b 0 )] and Im[W m (a 0 ,b 0 )] represent the real and imaginary parts of W m (a 0 ,b 0 ), respectively.
步骤6)所述的利用零光程差位置最优估计值,得到步骤2)所述像素点对应的高度信息H,是通过下式得到:The height information H corresponding to the pixel points in step 2) obtained by using the optimal estimated value of the zero optical path difference position in step 6) is obtained by the following formula:
H=H′+z0 (5)H=H′+z 0 (5)
其中,H′=NΔ,Δ表示扫描间距,N为采样光强最大值位置对应的扫描步数,z0为零光程差位置的最优估计值。Among them, H′=NΔ, Δ represents the scanning distance, N is the number of scanning steps corresponding to the position of the maximum sampling light intensity, and z 0 is the optimal estimated value of the position of zero optical path difference.
本发明的基于彩色条纹信息处理的微结构测量系统及测量方法,使用CCD彩色相机采集白光干涉条纹图像,与传统地使用灰度图像测量物体形貌相比,可以有效的减小环境噪声的影响,提高测量精度。The microstructure measurement system and measurement method based on color fringe information processing of the present invention uses a CCD color camera to collect white light interference fringe images, which can effectively reduce the impact of environmental noise compared with the traditional use of grayscale images to measure the shape of objects , improve measurement accuracy.
附图说明Description of drawings
图1是本发明微结构测量系统的整体结构示意图;Fig. 1 is the overall structure schematic diagram of microstructure measurement system of the present invention;
图2a是不使用白平衡滤光片,R、G、B光强的相对强度示意图;Figure 2a is a schematic diagram of the relative intensities of R, G, and B light intensities without using a white balance filter;
图2b是使用白平衡滤光片,R、G、B光强的相对强度示意图;Figure 2b is a schematic diagram of the relative intensity of R, G, and B light intensities using a white balance filter;
图3是本发明方法的流程图;Fig. 3 is the flowchart of the inventive method;
图4a是某像素点的R通道光强分布图;Figure 4a is an R channel light intensity distribution diagram of a certain pixel point;
图4b是某像素点的G通道光强分布图;Figure 4b is a light intensity distribution diagram of the G channel of a certain pixel point;
图4c是某像素点的B通道光强分布图;Figure 4c is a B-channel light intensity distribution diagram of a certain pixel point;
图5是零光程位置附近某像素点的R、G、B通道相位分布图;Fig. 5 is the R, G, B channel phase distribution diagram of a pixel near the zero optical path position;
图6是评价函数示意图。Fig. 6 is a schematic diagram of the evaluation function.
图中in the picture
具体实施方式Detailed ways
下面结合实施例和附图对本发明的基于彩色条纹信息处理的微结构测量系统及测量方法做出详细说明。The microstructure measurement system and measurement method based on the color fringe information processing of the present invention will be described in detail below in conjunction with the embodiments and the accompanying drawings.
如图1所示,基于彩色条纹信息处理的微结构测量系统,包括有Zeiss光学显微镜2,Zeiss光学显微镜2的光源输入端设置有具有宽光谱特性的卤素灯1,Zeiss光学显微镜2的样品扫描端设置有用于对样品9进行垂直扫描,并与计算机8相连的扫描机构,Zeiss光学显微镜2的信号采集端依次设置有Basler公司的型号为avA1600-65kc的CCD彩色相机6,与CCD彩色相机6相连的NI公司的PCI-1428图像采集卡7,实现图像的采集,所述的图像采集卡7还连接计算机8,可在计算机中观察图像。计算机包含了系统的软件部分,主要包括使用LabVIEW实现图像的采集和使用MATLAB实现数据的处理。在所述的Zeiss光学显微镜2与所述的卤素灯1之间设置有用于降低蓝色波段以外波段光透射率的白平衡滤光片11。As shown in Figure 1, the microstructure measurement system based on color fringe information processing includes a Zeiss
如图2a、图2b所示,在照明光源处加入一个白平衡滤光片,可以起到降低其他波段(除蓝色波段外)光的透射率的作用。图2a中不使用白平衡滤光片时,蓝色波段的光信号信噪比很低;图2b中使用滤光片后反映了通过增大光源的输出光强,绿色和蓝色波段的光强得到增强,红色波段的光强被衰减,使得绿色和蓝色波段光谱的信噪比得到提高,同时,CCD相机并没有因为光源输出光强的增大而处于饱和工作状态,提高了信号的利用率。As shown in Figure 2a and Figure 2b, adding a white balance filter at the illumination source can reduce the transmittance of light in other bands (except the blue band). When the white balance filter is not used in Figure 2a, the signal-to-noise ratio of the blue band is very low; after using the filter in Figure 2b, it reflects that by increasing the output light intensity of the light source, the light in the green and blue bands The intensity of the red band is enhanced, and the light intensity of the red band is attenuated, so that the signal-to-noise ratio of the green and blue band spectra is improved. utilization rate.
所述的扫描机构包括有与Zeiss光学显微镜2样品扫描端对应设置的物镜纳米定位器4和与所述的物镜纳米定位器4相连的压电控制器5,所述的物镜纳米定位器4选用PI公司生产的型号为PIP-721.CL的产品,压电控制器5选用PI公司生产的型号为E-509.C1A的产品,所述的压电控制器5通过RS232连接计算机8,所述的物镜纳米定位器4连接在Mirau型干涉物镜3上,所述的Mirau型干涉物镜3采用由Nikon公司生产的Mirau型干涉物镜(放大倍率为10X,数值孔径N.A.为0.30),所述的干涉物镜3与设置在实验台10上的样品9相对应设置。Described scanning mechanism comprises the
如图3所示,本发明的基于彩色条纹信息处理的微结构测量系统及测量方法,包括如下步骤:As shown in Figure 3, the microstructure measurement system and measurement method based on color fringe information processing of the present invention include the following steps:
1)对CCD彩色相机采集的一组原始图像进行拜尔反变换,得到真实的彩色图像信息;1) Perform inverse Bayer transformation on a group of original images collected by a CCD color camera to obtain real color image information;
2)分别提取由步骤1)变换得到的彩色图像任一像素点的R(红)、G(绿)和B(蓝)通道光强信息,进而得到不同扫描位置处R、G、B的光强值;2) Extract the R (red), G (green) and B (blue) channel light intensity information of any pixel of the color image transformed by step 1), and then obtain the light intensity information of R, G, and B at different scanning positions. Strong value;
所述的任一像素点的R、G和B的光强值是由下式得到:The light intensity values of R, G and B of any pixel point are obtained by the following formula:
其中,m分别表示为R、G、B,代表CCD彩色相机的R、G、B通道;I0m表示背景光强,反映光强的直流分量;γm表示条纹可见度;λcm表示光源在对应通道的中心波长;z表示物镜纳米定位器垂直扫描的位置,当发生干涉的两光束光程差为零时,物镜纳米定位器所在的位置表示为z0,这个位置简称为零光程差位置;g(zm-z0)是相干包络项,由光源在相应通道的光谱特征决定。Among them, m are represented as R, G, and B respectively, representing the R, G, and B channels of the CCD color camera; I 0m represents the background light intensity, reflecting the DC component of light intensity; γ m represents the visibility of stripes; λ cm represents the light source in the corresponding The central wavelength of the channel; z represents the vertical scanning position of the objective lens nanopositioner, when the optical path difference between the two beams that interfere is zero, the position of the objective lens nanopositioner is expressed as z 0 , and this position is referred to as the zero optical path difference position ; g(z m -z 0 ) is the coherent envelope item, which is determined by the spectral characteristics of the light source in the corresponding channel.
实验中使用的光源卤素灯在R、G、B通道的光谱均呈现高斯(Gauss)分布的特点,因而,所述的相干包络项表示为The light source halogen lamp used in the experiment has the characteristics of Gauss distribution in the spectra of R, G, and B channels. Therefore, the coherent envelope term is expressed as
其中,lcm表示光源在对应通道的相干长度,在R、G、B通道中,只有在零光程差位置z0附近才会有干涉条纹的分布。Among them, l cm represents the coherence length of the light source in the corresponding channel. In the R, G, and B channels, there will be interference fringes only near the zero optical path difference position z 0 .
3)选择Morlet小波作为小波变换的母小波,对步骤2)得到的R、G、B通道的光强值做一维连续小波变换,利用变换结果计算R、G、B通道的相位信息;3) Select the Morlet wavelet as the mother wavelet of the wavelet transform, perform one-dimensional continuous wavelet transform on the light intensity values of the R, G, and B channels obtained in step 2), and use the transformation results to calculate the phase information of the R, G, and B channels;
所述的R、G、B通道相位信息,是通过下述三步得到:The phase information of the R, G, and B channels is obtained through the following three steps:
第一步,选择Morlet小波作为小波变换的母小波,即由于信号Im呈现出高斯分布的特征,而Morlet小波事实上是由高斯函数调制而成的,所以选择Morlet小波作为小波变换的母小波。In the first step, Morlet wavelet is selected as the mother wavelet of wavelet transform, namely Since the signal Im presents the characteristics of Gaussian distribution, and Morlet wavelet is actually modulated by Gaussian function, Morlet wavelet is chosen as the mother wavelet of wavelet transformation.
第二步,对Im(z)进行一维连续小波变换得到:In the second step, one-dimensional continuous wavelet transform is performed on I m (z) to obtain:
其中,ψ(z)为小波变换的母小波,a,b分别表示小波变换的尺度因子和平移因子,
第三步,R、G、B通道相位信息通过Wm(a,b)的辐角即The third step, R, G, B channel phase information Through the argument of W m (a,b) that is
得到,其中,a0,b0为Wm(a,b)的模值最大时对应的尺度因子和平移因子,Re[Wm(a0,b0)]和Im[Wm(a0,b0)]分别表示Wm(a0,b0)的实部和虚部,如图5所示。通过对Im(z)进行一维连续小波变换得到的Wm(a,b)反映了ψab与Im的相关程度。尺度因子a的变化反映了信号Im频率的变化,平移因子b的变化反映了信号Im位移的变化,通过尺度因子a和平移因子b的连续变化,可求得在不同频率和位移处ψab与Im相关程度的大小。在某一扫描位置处,当ψab(z)与Im(z)相关程度最高,即Wm(a,b)的模值最大时,Wm(a,b)的辐角即为该扫描位置处Im(z)的相位值。Obtained, where a 0 , b 0 is the scale factor and translation factor corresponding to the maximum modulus value of W m (a,b), Re[W m (a 0 ,b 0 )] and Im[W m (a 0 ,b 0 )] represent the real part and imaginary part of W m (a 0 ,b 0 ), respectively, as shown in Figure 5. W m (a,b) obtained by performing one-dimensional continuous wavelet transform on Im (z) reflects the degree of correlation between ψ ab and Im . The change of the scale factor a reflects the frequency change of the signal Im , and the change of the translation factor b reflects the change of the displacement of the signal Im . Through the continuous change of the scale factor a and the translation factor b, the ψ at different frequencies and displacements can be obtained The degree of correlation between ab and Im . At a certain scanning position, when ψ ab (z) has the highest correlation with I m (z), that is, when the modulus of W m (a, b) is the largest, the argument of W m (a, b) is the Phase value of Im (z) at the scan position.
4)对步骤3)得到的R、G、B通道的相位信息,基于如图6所示的构造的评价函数初步确定零光程差的位置,此时评价函数在零光程差位置处有最小值;4) For the phase information of the R, G, and B channels obtained in step 3), based on the evaluation function constructed as shown in Figure 6 Preliminarily determine the position of zero optical path difference, at this time, the evaluation function has a minimum value at the position of zero optical path difference;
5)选取零光程差附近R、G、B通道的相位信息,对所述R、G、B通道的相位信息做最小二乘拟合得到零光程差位置最优估计值,即精确确定零光程差的位置。5) Select the phase information of the R, G, and B channels near zero optical path difference, and perform least squares fitting on the phase information of the R, G, and B channels to obtain the optimal estimated value of the zero optical path difference position, that is, accurately determine The position of zero optical path difference.
实际测量过程中,测量误差使得R、G、B的零光程差位置并不在同一位置处,为获得零光程差位置的最优估计值,运用最小二乘法确定。In the actual measurement process, measurement errors make the zero optical path difference positions of R, G, and B not at the same position. In order to obtain the optimal estimated value of the zero optical path difference position, the least square method is used to determine it.
R、G、B通道的相位信息可表示为其中,Am=4π/λcm,Bm=-4πz0/λcm。根据最小二乘法原理,零光程差位置z0的最优估计值可在有最小值时求得,此时需满足条件The phase information of R, G, and B channels can be expressed as Among them, A m =4π/λ cm , B m =-4πz 0 /λ cm . According to the principle of the least square method, the optimal estimated value of the zero optical path difference position z 0 can be found in It is obtained when there is a minimum value, and the condition needs to be met at this time
可得零光程差位置z0的最优估计值为It can be obtained that the optimal estimated value of the zero optical path difference position z 0 is
确定Am,Bm的方法如下:首先通过评价函数EF初步确定零光程差的位置,进而对零级条纹内的采样点做分析。采样点满足函数关系The method of determining A m and B m is as follows: firstly, the position of zero optical path difference is preliminarily determined through the evaluation function EF, and then the sampling point in the zero-order fringe Do analysis. Sampling point Satisfy the functional relationship
根据最小二乘法原理,公式(7)中的Am,Bm满足以下条件关系式:According to the principle of the least square method, A m and B m in formula (7) satisfy the following conditional relationship:
可得Available
即可求得Am,Bm的数值,进而求得零光程差位置z0的最优估计值。最优估计值z0局限于零级条纹内,其实质是采样光强最大值位置与零光程差位置的偏差值。The values of A m and B m can be obtained, and then the optimal estimated value of the zero optical path difference position z 0 can be obtained. The optimal estimated value z 0 is limited to the zero-order fringe, which is essentially the deviation between the position of the maximum value of the sampled light intensity and the position of zero optical path difference.
6)利用步骤5)得到的零光程差位置最优估计值,得到步骤2)所述像素点对应的高度信息,所述的高度信息H是通过下式得到:6) Using the optimal estimated value of the zero optical path difference position obtained in step 5), the height information corresponding to the pixel point in step 2) is obtained, and the height information H is obtained by the following formula:
H=H′+z0 (10)H=H′+z 0 (10)
其中,H′=NΔ,Δ表示扫描间距,N为采样光强最大值位置对应的扫描步数,z0为零光程差位置的最优估计值。Among them, H′=NΔ, Δ represents the scanning distance, N is the number of scanning steps corresponding to the position of the maximum sampling light intensity, and z 0 is the optimal estimated value of the position of zero optical path difference.
7)对步骤1)变换得到的彩色图像的其它像素点分别做与步骤2)至步骤6)相同的处理,从而得到不同像素点对应的高度信息,最终得到物体的表面形貌。7) Perform the same processing as steps 2) to 6) on the other pixels of the color image transformed in step 1), so as to obtain the height information corresponding to different pixels, and finally obtain the surface topography of the object.
本发明利用单CCD彩色相机采集白光干涉彩色条纹的图像。此外,不同于加窗傅立叶变换的方法,由于小波变换的理论日臻成熟,应用日益广泛,本发明选用了连续小波变换法对R、G、B三个通道的图像信息进行分析,从而获得被测物体的几何尺寸及表面形貌。The invention utilizes a single CCD color camera to collect images of white light interference color fringes. In addition, different from the method of windowed Fourier transform, since the theory of wavelet transform is becoming more and more mature and its application is becoming more and more extensive, the present invention uses the continuous wavelet transform method to analyze the image information of the three channels of R, G, and B, so as to obtain the measured The geometric size and surface shape of the object.
Claims (8)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201410027013.8A CN103791853A (en) | 2014-01-20 | 2014-01-20 | Microstructure measuring device and measuring method based on color strip information processing |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201410027013.8A CN103791853A (en) | 2014-01-20 | 2014-01-20 | Microstructure measuring device and measuring method based on color strip information processing |
Publications (1)
Publication Number | Publication Date |
---|---|
CN103791853A true CN103791853A (en) | 2014-05-14 |
Family
ID=50667742
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201410027013.8A Pending CN103791853A (en) | 2014-01-20 | 2014-01-20 | Microstructure measuring device and measuring method based on color strip information processing |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN103791853A (en) |
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105865370A (en) * | 2016-05-23 | 2016-08-17 | 华南师范大学 | White-light scanning interferometry measurement method and system |
CN106017349A (en) * | 2016-06-08 | 2016-10-12 | 中国计量大学 | White light interferometry-based test system and test method therefor |
CN106017303A (en) * | 2015-03-26 | 2016-10-12 | Snu精密股份有限公司 | Method for compensating error of fringe order in white-light phase-shifting interferometry |
CN106123805A (en) * | 2016-08-15 | 2016-11-16 | 华南师范大学 | The plated film device three-dimensional topography measurement method interfered based on white light scanning |
CN106197310A (en) * | 2016-06-29 | 2016-12-07 | 中国科学院光电技术研究所 | Modulation degree-based wide-spectrum micro-nano structure three-dimensional morphology detection method |
CN106247980A (en) * | 2016-08-22 | 2016-12-21 | 天津大学 | The multi-wavelength phase shift interference measuring method processed based on white light interference color fringe |
CN108759709A (en) * | 2018-03-15 | 2018-11-06 | 北京航空航天大学 | A kind of white light interference three-dimensional rebuilding method suitable for surface profile measurement |
CN110095081A (en) * | 2019-03-25 | 2019-08-06 | 华中农业大学 | A kind of method and measuring device based on spatial frequency domain imaging measurement organizer's pattern and optical parameter |
WO2020042190A1 (en) * | 2018-08-31 | 2020-03-05 | 苏州大学张家港工业技术研究院 | Method and device for measuring microstructure topography based on dispersion spectrum coding |
CN113847883A (en) * | 2021-09-09 | 2021-12-28 | 南京理工大学 | Interferometric method suitable for detecting three-dimensional shape of high aspect ratio structure |
Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4641971A (en) * | 1983-12-27 | 1987-02-10 | International Business Machines Corporation | White light interferometer |
US6292277B1 (en) * | 1998-10-16 | 2001-09-18 | Lextron Systems, Inc. | Method and apparatus for creating a white-light interference hologram from PC input photographic data |
US20050185192A1 (en) * | 2004-02-20 | 2005-08-25 | Kim Myung K. | Method of full-color optical coherence tomography |
JP2008020318A (en) * | 2006-07-12 | 2008-01-31 | Tokyo Univ Of Agriculture & Technology | Film thickness measuring apparatus and film thickness measuring method |
CN201666783U (en) * | 2010-04-23 | 2010-12-08 | 浙江大学 | A white light interferometer with fast zeroing system |
CN101949692A (en) * | 2010-09-07 | 2011-01-19 | 天津大学 | Microstructure topography test system and method based on white light phase shift interferometry |
WO2011014282A2 (en) * | 2009-05-01 | 2011-02-03 | Trustees Of Boston University | High magnification spectral reflectance biosensing with discrete light sources |
US20120156636A1 (en) * | 2009-05-15 | 2012-06-21 | Degudent Gmbh | Method and measuring arrangement for the three-dimensional measurement of an object |
CN102944187A (en) * | 2012-10-18 | 2013-02-27 | 北京航空航天大学 | Method for acquiring phase position of fast bright reflection surface on basis of color stripe permutation projection |
-
2014
- 2014-01-20 CN CN201410027013.8A patent/CN103791853A/en active Pending
Patent Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4641971A (en) * | 1983-12-27 | 1987-02-10 | International Business Machines Corporation | White light interferometer |
US6292277B1 (en) * | 1998-10-16 | 2001-09-18 | Lextron Systems, Inc. | Method and apparatus for creating a white-light interference hologram from PC input photographic data |
US20050185192A1 (en) * | 2004-02-20 | 2005-08-25 | Kim Myung K. | Method of full-color optical coherence tomography |
JP2008020318A (en) * | 2006-07-12 | 2008-01-31 | Tokyo Univ Of Agriculture & Technology | Film thickness measuring apparatus and film thickness measuring method |
WO2011014282A2 (en) * | 2009-05-01 | 2011-02-03 | Trustees Of Boston University | High magnification spectral reflectance biosensing with discrete light sources |
WO2011014282A3 (en) * | 2009-05-01 | 2011-03-31 | Trustees Of Boston University | High magnification spectral reflectance biosensing with discrete light sources |
US20120156636A1 (en) * | 2009-05-15 | 2012-06-21 | Degudent Gmbh | Method and measuring arrangement for the three-dimensional measurement of an object |
CN201666783U (en) * | 2010-04-23 | 2010-12-08 | 浙江大学 | A white light interferometer with fast zeroing system |
CN101949692A (en) * | 2010-09-07 | 2011-01-19 | 天津大学 | Microstructure topography test system and method based on white light phase shift interferometry |
CN102944187A (en) * | 2012-10-18 | 2013-02-27 | 北京航空航天大学 | Method for acquiring phase position of fast bright reflection surface on basis of color stripe permutation projection |
Non-Patent Citations (8)
Title |
---|
GUO TONG等: "Micro-structure characterization based on white light interferometry", 《PROC. OF SPIE》 * |
GUO TONG等: "Scanning White-light Interferometry for Microstructures Geometrical Characterization", 《PROC. OF SPIE》 * |
SUODONG MA等: "Surface profile measurement in white-light scanning interferometry using a three-chip color CCD", 《APPLIED OPTICS》 * |
ZDENĚK BUCHTA等: "White-light interference fringe detection using color CCD camera", 《IEEE AFRICON》 * |
刘宝琛等: "白光信息处理干涉条纹倍增技术", 《清华大学学报》 * |
郭彤等: "垂直扫描白光干涉术用于微机电系统的尺寸表征", 《光学学报》 * |
马锁冬: "基于相位恢复的三维形貌复合通道测量技术研究及应用", 《中国博士学位论文全文数据库 信息科技辑》 * |
马龙等: "基于白光相移干涉技术的微结构几何尺寸表征", 《纳米技术与精密工程》 * |
Cited By (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN106017303B (en) * | 2015-03-26 | 2019-04-19 | Snu精密股份有限公司 | The method for correcting the error of the fringe order in white light phase shifting interferometer |
CN106017303A (en) * | 2015-03-26 | 2016-10-12 | Snu精密股份有限公司 | Method for compensating error of fringe order in white-light phase-shifting interferometry |
CN105865370A (en) * | 2016-05-23 | 2016-08-17 | 华南师范大学 | White-light scanning interferometry measurement method and system |
CN105865370B (en) * | 2016-05-23 | 2019-04-19 | 华南师范大学 | A white light scanning interferometry method and system |
CN106017349A (en) * | 2016-06-08 | 2016-10-12 | 中国计量大学 | White light interferometry-based test system and test method therefor |
CN106197310A (en) * | 2016-06-29 | 2016-12-07 | 中国科学院光电技术研究所 | Modulation degree-based wide-spectrum micro-nano structure three-dimensional morphology detection method |
CN106123805B (en) * | 2016-08-15 | 2019-04-30 | 华南师范大学 | Three-dimensional topography measurement method of coated devices based on white light scanning interference |
CN106123805A (en) * | 2016-08-15 | 2016-11-16 | 华南师范大学 | The plated film device three-dimensional topography measurement method interfered based on white light scanning |
CN106247980A (en) * | 2016-08-22 | 2016-12-21 | 天津大学 | The multi-wavelength phase shift interference measuring method processed based on white light interference color fringe |
CN108759709A (en) * | 2018-03-15 | 2018-11-06 | 北京航空航天大学 | A kind of white light interference three-dimensional rebuilding method suitable for surface profile measurement |
CN108759709B (en) * | 2018-03-15 | 2020-03-27 | 北京航空航天大学 | A white light interference 3D reconstruction method suitable for surface topography detection |
WO2020042190A1 (en) * | 2018-08-31 | 2020-03-05 | 苏州大学张家港工业技术研究院 | Method and device for measuring microstructure topography based on dispersion spectrum coding |
CN110095081A (en) * | 2019-03-25 | 2019-08-06 | 华中农业大学 | A kind of method and measuring device based on spatial frequency domain imaging measurement organizer's pattern and optical parameter |
CN113847883A (en) * | 2021-09-09 | 2021-12-28 | 南京理工大学 | Interferometric method suitable for detecting three-dimensional shape of high aspect ratio structure |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN103791853A (en) | Microstructure measuring device and measuring method based on color strip information processing | |
CN109141224B (en) | An Interferometric Reflection Optical Thin Film Microscopic Measurement Method Based on Structured Light | |
CN108319009B (en) | Fast super-resolution imaging method based on structured light modulation | |
CN106643559B (en) | White light microscopic interference morphology reconstruction method based on mixed interference fringes | |
CN109916331B (en) | Three-dimensional detection method for structured light micro-nano structure based on composite grating | |
CN109341574B (en) | Micro-nano structure three-dimensional morphology high-speed detection method based on structured light | |
KR101486271B1 (en) | Measuring Method For Three-dimensional Thickness Profile | |
KR101005179B1 (en) | Method and apparatus for measuring OCD using optical interference | |
CN103630086A (en) | Dual-wavelength simultaneous phase-shift interferometry method based on monochromatic CCD (couple charged device) | |
CN105865370B (en) | A white light scanning interferometry method and system | |
CN101655360A (en) | 16-step dual-frequency grating phase shift profilometry capable of absolute phase unwrapping | |
CN113091634A (en) | Rapid micro-morphology measuring method suitable for white light scanning interference | |
TW200930995A (en) | Method and apparatus for identifying dynamic characteristics of a vibratory object | |
US20160266057A1 (en) | System and method for phase retrieval in lensless imaging | |
CN106813596A (en) | A kind of self-calibration shadow Moire measuring three-dimensional profile method | |
CN106197310A (en) | Modulation degree-based wide-spectrum micro-nano structure three-dimensional morphology detection method | |
CN106643558A (en) | Wide spectrum interference morphology detection method based on phase longitudinal splicing | |
CN209085560U (en) | A color confocal three-dimensional topography optical measurement mechanism | |
CN106247980A (en) | The multi-wavelength phase shift interference measuring method processed based on white light interference color fringe | |
CN105277136B (en) | Transmission microscope imaging device and method based on dual-wavelength digital holography technology | |
CN113175894A (en) | Object surface three-dimensional shape white light interferometry device and method | |
CN106556340A (en) | Method for searching zero-order fringe of wide-spectrum interference based on modulation degree | |
CN103217096B (en) | A kind of three window synchronization phase-shifting interferometers | |
CN109297595B (en) | Optical coherence tomography phase unwrapping method and device | |
Xin et al. | A white-light interferometry method for 3D measurement of compactly spaced micro-nano structural units |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
C06 | Publication | ||
PB01 | Publication | ||
C10 | Entry into substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20140514 |