The disclosure herein relates to the technical field of optical imaging and computer, and in particular to quantitative phase imaging.
Light microscopes are important tools for research in biology, medicine, material science, and so on. Among them, fluorescence microscopy has been a standard imaging modality for modern cell biology investigations, where targeted cell compartments are labelled with fluorescence tags. Phase-contrast microscopy, as another widely used method, is suitable for observing live cells with improved contrast compared with bright-field microscopy. In recent years, quantitative phase microscopy (QPM), offering precise mapping of sample's refractive index (RI) and thickness distributions, has emerged as an important label-free imaging tool for biological and material structures, e.g., mapping cell morphology, quantification of cell dynamics, digital histopathology, surface profiling of fabricated material structures, detecting defects in patterned silicon wafers, etc.
To make QPM system compact and cost effective to broaden its use, various efforts have been made, such as implementing twin-beam optical design, t interferometer, self-interference with a Wollaston prism, common-path design with pinhole diffraction, on-chip computational imaging, etc. To extend the depth measurement range in off-axis QPM, dual wavelength or three wavelength methods have been invented. To simultaneous offer morphological and molecular information, QPM and fluorescence imaging has been integrated into the imaging platform. On the other hand, obtaining molecular information in a label-free way can simplify sample preparation and minimize perturbations, especially for live biological samples. Spectroscopy methods, such as those based on Raman spectroscopy, absorption spectroscopy, and sample dispersion, can be used to probe molecular compositions in specimen in a label-free manner.
researchers have retrieved dispersion and absorbance properties of proteins and DNA solutions, measured absorption coefficients and refractive index spectra in dispersive samples, quantified hemoglobin concentrations in red blood cells, etc. However, for a comprehensive study of biological and material structures, multiple information dimensions are re-quired (e.g., sample morphology, molecular information, quantification of molecular concentrations, etc.), and specific measurement conditions (e.g., high-speed mapping of sample properties, samples with large thickness, etc.) need to be satisfied. Despite of the various efforts in developing hybrid imaging modalities, there has not been a compact and ease-of-use system that embodies versatile measurement functions for more comprehensive studies in biology and material studies.
The disclosure herein provides a device, method, and computer-readable storage medium for quantitative phase imaging.
According to an aspect of the disclosure herein, there is provided advice for quantitative phase imaging, comprising:
According to another aspect of the disclosure herein, there is provided a method for quantitative phase imaging, comprising:
According to another aspect of the disclosure herein, there is provided a non-transitory computer-readable storage medium storing computer instructions, which are used to make a computer execute the method in any embodiment of the disclosure herein.
According to another aspect of the disclosure herein, there is provided a computer program product, including a computer program, which, when executed by a processor, implements the method in any embodiment of the disclosure herein.
According to the technology of the disclosure herein, a sample can be illuminated with a sample beam synthesized of two or more beams with different wavelengths, and after illumination the sample beam combines with reference beams that synthesizes the sample beam to form a multiplexed interferogram on a camera, thus the disclosure herein can capture an interference pattern of multiple light beams with different wavelengths in one acquisition. And the phase map of each wavelength channel can be reconstructed as the sample information corresponding to these two or more wavelengths in the interference pattern does not overlap in the spatial frequency space. Therefore, in the case of one acquisition and one phase retrieval, the phase maps of the sample in multiple wavelength channels can be obtained, which greatly improves the work efficiency of phase imaging.
It should be understood that the content described in this section is not intended to identify key or important features of the embodiments of the disclosure herein, nor is it intended to limit the scope of the disclosure herein. Other features of the disclosure herein will be easily understood through the following description.
The drawings are used to better understand the solution of the disclosure, and do not constitute a limitation to the disclosure herein.
The following describes exemplary embodiments of the disclosure herein with reference to the accompanying drawings, which include various details of the embodiments of the disclosure herein to facilitate understanding, and should be regarded as merely exemplary. Therefore, those of ordinary skill in the art should recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the disclosure herein. Likewise, for clarity and conciseness, descriptions of well-known functions and structures are omitted in the following description.
In order to facilitate the understanding of the technical solutions of the embodiments of the disclosure herein, the related technologies of the embodiments of the disclosure herein are described below. The following related technologies can be combined with the technical solutions of the disclosure embodiments as optional solutions, and they all belong to the scope of the disclosure herein.
In order to satisfy various imaging applications under different experimental conditions, the disclosure embodiments propose a device for quantitative phase imaging, which can be referred to as a portable multi-modal and multi-wavelength fiber-based quantitative phase microscope (M2QPM). In the proposed device, two or more lights of different wavelengths are multiplexed into an interferogram, from which the quantitative phase maps of the lights of two different wavelengths can be retrieved for profiling samples with extended depth. Moreover, the device uses fiber optic components to propagate sample beams and reference beams, and it is carefully adjusted the length of the optical path in the fiber to achieve off-axis interference measurement, which also improves the stability and compactness of the device for quantitative phase imaging. Based on the hardware structure of the quantitative phase imaging device itself and the multiplexed interferogram obtained by imaging, the disclosure embodiments can open up a variety of applications, such as various parameters of the sample can be measured in real time, including thickness, refractive index, morphological information, fluorescence information, absorption characteristics, etc.
In one application, according to phase mapsat two or more different wavelengths of light used in imaging, a physical model can be derived to map dispersion parameters of samples, which can be used to characterize dispersive samples in real time, such as hemoglobin concentration of red blood cells.
In one application, the phase maps of light of two or more different wavelengths is used to phase unwrap the synthesized phase map of the light synthesized by these lights, and then based on the unwrapped synthesized phase map and the synthetic wavelength synthesized of wavelengths of these lights. calculate the height map of the sample, which can truly reflect sample profiles.
In one application, based on the device for quantitative phase imaging, an appropriate fluorescence filter can be arranged in front of the camera plane to realize fluorescence imaging, and with quantitative phase imaging applied to cell imaging. Fluorescence imaging and phase imaging can pass through the same optical system and use the same camera. It is only necessary to add an appropriate fluorescence filter in front of the camera plane during fluorescence imaging, without using dichroic mirrors for separation.
Hereinafter, the imaging device and various imaging applications proposed by the disclosure embodiments will be exemplified.
Refer to
The number of light sources, fiber couplers and cubic beam splitters can be the same or different. The number of fiber couplers and cubic beam splitters can be the same.
Exemplarily, as shown in
Illustratively, in the M2QPM system, three or more light sources, three fiber couplers and three cubic beam splitters are provided. During the imaging process, three of the light sources can be selected from more than three light sources to be connected to the three fiber couplers respectively, that is, one light source is connected to one fiber coupler. Each fiber coupler divides the input light into two beams, one beam is input to the fiber combiner through an optical fiber, and the other beam is connected to a cubic beam splitter through an optical fiber as the reference beam. This example can realize the multiplexed interference of three-wavelength light.
For the multiplexed interference of light of four or more wavelengths, it can be referred to these two examples for setting.
The disclosure embodiments take
As shown in
The cubic beam splitter is equipped with a second collimator lens to expand and collimate the reference beam, which would enter the cube beam splitter with appropriate beam sizes. A kinematic mount is installed at the input end of the second collimator lens, which can adjust the angle of the input reference beam.
The sample beam is amplified by the 4f system and combined with the two reference beams incident on the two cube beam splitters through two cube beam splitters to form a multiplexed interference pattern on the camera. Exemplarily, the wavelengths of the two light sources in
The disclosure embodiments can illuminate a sample with a sample beam synthesized by two or more beams with different wavelengths, and use the beams participating in the synthesis of the sample beam as the reference beams, which are combined with the sample beam after irradiating the sample, so that the camera can capture their interference pattern in a single acquisition. Moreover, since the sample information corresponding to these two or more wavelengths in the interference pattern does not overlap in the spatial frequency space, the phase map of each wavelength channel can be reconstructed. Therefore, in the case of one acquisition and one phase retrieval, the phase maps of the sample in multiple wavelength channels can be obtained, which greatly improves the work efficiency.
In addition, in the M2QPM system, the use of fiber optic components such as fiber couplers, fiber combiners and cubic beam splitters helps to reduce the space of the system. In order to further take the advantages of optical fiber and ensure interference with a minimized system dimension, a piece of optical fiber can be spliced in each output of each fiber coupler to connect to the fiber combiner and cube beam splitter. The length of the spliced fiber is determined by matching the total optical path length of the two output beams from the fiber coupler. Since the optical fiber can be folded and coiled, and most of the optical path of the light beam is in the coiled fiber during propagation, the light beam can be folded to minimize the extension of the imaging device.
The imaging device provided by the disclosure embodiments may also include a processor for data processing and analysis of the imaging map of the device to open up new applications, such as real-time measurement of various parameters of the sample, including phase, thickness, refractive index, morphological information, fluorescence information and absorption characteristics, etc.
The disclosure embodiments can obtain the interference pattern of a sample illuminated by multiple wavelength-combined beams in one collection. As the sample information corresponding to multiple wavelengths does not overlap in the spatial frequency space, the phase retrieval algorithm based on the Fourier transform can reconstruct the phase map of the sample in each wavelength channel.
In the M2QPM system, the same optical system and the same camera can be used for fluorescence imaging and phase imaging, and there is no need to use dichroic mirrors for separation. In fluorescence imaging, the sample is coated with fluorescent dyes in advance, and a band-pass filter is placed in front of the camera plane. The fluorescent dye has a maximum excitation wavelength and a maximum emission wavelength. Since the imaging device of the disclosure herein is provided with multiple light sources of different wavelengths, a appropriate excitation light source can be selected from them to perform fluorescence imaging. At the same time, the cut-off wavelength of the band-pass filter should also meet the wavelength requirements of the excitation light source and the fluorescent dye. That is, the wavelength of the excitation light source needs to be greater than the maximum excitation wavelength of the fluorescent dye. The cut-off wavelength of the pass filter is between the wavelength of the excitation light source and the maximum emission wavelength of the fluorescent dye. The process of fluorescence imaging is as follows: the excitation light source emits a light beam and illuminates the sample on the sample platform through the first collimator lens to make the sample emit fluorescence, and the fluorescence sequentially passes through the 4f system and the at least two cubic beam splitter, thus the camera captures the fluorescence image of the sample.
After obtaining the fluorescence image of the sample, one of the light sources can be selected from multiple light sources for quantitative phase imaging, which is single-wavelength phase imaging.
Exemplarily, before imaging, fiber cells are stained with 0.1 mg/ml Nile Blue Sulfate. Then, the dyed fiber cells are placed on the sample platform of the imaging device for fluorescence imaging. The maximum excitation wavelength of Nile blue sulfate is 620 nm, and the maximum emission wavelength is 680 nm. Taking
Generally speaking, in quantitative phase imaging, for objects (samples) whose optical depth is greater than the wavelength of illumination, the phase image contains 2π discontinuities. However, most of the existing phase unwrapping algorithms used to eliminate discontinuities require subjective intervention, such as the Goldstein phase unwrapping algorithm. In order to solve the problem of discontinuity in the phase map obtained when the height step of the sample is greater than the wavelength of the light irradiating the sample, an embodiment of the disclosure herein proposes a phase unwrapping method that uses the phase maps of the sample at two wavelengths to create a synthesized phase map corresponding to the synthetic wavelength, and unwrap the synthesized phase map of the synthetic wavelength.
Taking
Exemplarily, the first wavelength λ1 is 633 nm, and the second wavelength λ2 is 532 nm. According to the following equation (1), the synthetic wavelength A is calculated to be 3334.2 nm.
The phase map of the sample at the first wavelength λ1 isφ1 (x,y), and the phase map of the sample at the second wavelength λ2 isφ2 (x,y). Subtract the two phase maps to obtain the phase map corresponding to the synthetic wavelength, as shown in the following formula:
Due to the mismatch between the two wrapping phase maps at these two wavelengths, there may be some phase jumps. When there is a negative phase in the synthesized phase map, add a period of 2π to the negative phase to solve the above-mentioned mismatch problem, thereby performing phase unwrapping.
For the height map of the sample, it can be calculated according to the following formula:
Where Δn is the refractive index contrast between the main substance in the sample and the medium in the sample.
Based on formula (3), using the synthesized phase map to convert the phase to the height, the height map of the sample can still be calculated. Therefore, the sample height map calculated based on the synthesized phase map after unwrapping can truly reflect the height profile of the sample without subsequent interference processing. That is, for samples with an optical depth greater than the wavelength of illumination, the embodiments of the disclosure herein can still accurately measure the height, maintaining high phase sensitivity and stability.
The imaging device proposed in the disclosure embodiments can not only accurately measure the phase and height of the sample, but also can calculate the refractive index change of the sample in a single image through a multi-wavelength design, so as to further observe the dispersion and absorption characteristics of the sample in different wavelength ranges.
Taking
where H(x,y) is the height map, λ1 is the first wavelength, λ2 is the second wavelength, φ1(x,y) is the phase map of the sample at the first wavelength, and φ2(x,y) is the sample at the first wavelength. The phase map at the second wavelength, and Δn1 is the refractive index contrast between the sample and the medium at the first wavelength, and Δn2 is the refractive index contrast between the sample and the medium at the second wavelength.
Therefore, in combination with formula (4), the processor of the imaging device can determine a ratio of the refractive index of the sample at the first wavelength and at the second wavelength, according to the phase maps of the sample at the first wavelength and that at the second wavelength. Specifically, the ratio of refractive index at two wavelengths can be calculated based on the following formula:
Therefore, through the ratio of the refractive index of the sample at any two wavelengths, the dispersion and absorption characteristics of the sample at different wavelengths can be observed and analyzed.
Different types of molecules in the sample can be distinguished by their dispersion. For example, hemoglobin has obvious dispersion at the wavelength of visible light, so the distribution and concentration of hemoglobin in red blood cells can be calculated by measuring the dispersion characteristics of hemoglobin.
The process of calculating the hemoglobin concentration in red blood cells by the processor of the disclosure embodiments may be as follows:
Exemplarily, taking
where cHb is the hemoglobin concentration in red blood cells, nx is the relative average refractive index of other molecules in red blood cells except hemoglobin, which is an independent constant of wavelength, α(λ1) is the refractive index increment of hemoglobin at the first wavelength λ1, α(λ2) is the refractive index increment of hemoglobin at the second wavelength λ2,φ1 is the phase map of hemoglobin at the first wavelength λ1, and φ2 is the phase map of hemoglobin at the first wavelength λ2.
The imaging device of the embodiment of the disclosure herein may further include a display, which is used to display the image of the sample captured by the camera and the data and images or maps obtained after the processor processes the captured image.
Refer to
S100. Obtaining a multiplexed interferogram of a sample, where the multiplexed interferogram is an imaging map captured by a camera when a sample beam synthesized of at least two beams with different wavelengths to illuminate the sample and then penetrate into the cube beam splitter to combine with the at least two beams of different wavelengths as reference beams, and finally the combined beam is sampled by the camera.
S200. Performing a phase retrieval on the multiplexed interferogram to obtain a phase map of the sample at the wavelength of each beam that synthesizes the sample beam.
Exemplarily, here are at least two light beams with wavelengths of a first wavelength and a second wavelength that synthesizes the sample beam and as shown in
S300. Determining a synthesized phase map of the sample at the wavelength synthesized by the first wavelength and the second wavelength, according to the phase map of the sample at the first wavelength and that at the second wavelength.
S400. Adding a period of 2π on each negative phase in the synthesized phase map to obtain an unwrapping phase map.
Exemplarily, as shown in
S500. Performing a height conversion on the unwrapping phase map to obtain a height map of the sample.
Exemplarily, there are at least two light beams with wavelengths of a first wavelength and a second wavelength that synthesizes the sample beam and the method further comprises:
Determining a ratio of the refractive index of the sample at the first wavelength and at the second wavelength, according to the phase map of the sample at the first wavelength and that at the second wavelength.
Exemplarily, the sample is red blood cells, and the above method further includes:
Refer to
Exemplarily, there are at least two light beams with wavelengths of a first wavelength and a second wavelength that synthesizes the sample beam. As shown in
Exemplarily, as shown in
Exemplarily, there are at least two light beams with wavelengths of a first wavelength and a second wavelength that synthesizes the sample beam. As shown in
Illustratively, the sample is red blood cells. As shown in
Referring to
The system of this application example can be shown in
To further take the advantages of optical fibers and ensure interference with a minimized system dimension, this application example splices a section of optical fiber in each reference fiber arm of each fiber coupler. For this task, this application example uses a fiber cleaver, a fiber fusion splicer, and an extra piece single-mode fiber that matches the fiber type of fiber couplers. Lengths of the spliced fiber are determined by matching the total optical path length of the sample beam and the total optical path length of the reference beam. As the beam is mostly propagated in the coiled fiber, the beam is folded to minimize the extension of the system. The reference beams, namely reference 1 and reference 2, are expanded and collimated by lenses CL2 and CL3. Kinematic mounts installed at the inputs of the lenses CL2 and CL3 are used to adjust the angle of the reference beams. The sample beam is combined with the reference beam through two cube beam splitters BS1 and BS2 to form a multiplexed interferogram on a camera (FL3-U3-32S2M-CS, PointGrey). The multiplexed interferogram contains two sets of interference fringes at wavelengths of 633 nm and 532 nm.
On the camera sensor, this application example obtains two sets of almost vertical interference fringes, as shown in
The system of this application example is characterized to have a lateral resolution is 0.87 μm and a path-length measurement sensitivity of 0.9 nm for 633 nm wavelength, while 0.78 μm lateral resolution and a path-length measurement sensitivity of 0.7 nm for 532 nm wavelength illumination.
For the sensitivity analysis and calibration of the interference system, environmental factors such as mechanical vibration, air density fluctuations and instrument parameters such as camera dark noise, quantum efficiency and dynamic range of the cameras may all affect it. Phase noise is usually characterized by Optical Path-length Difference (OPD), which is an important factor affecting system performance and can be used to characterize the spatial and temporal sensitivity of a QPM system. The phase noise can be determined using the following formula:
As shown in formula (7), it refers to the highest theoretical shot noise limit sensitivity that can be achieved, where N is the maximum electron well depth of the camera. For the PointGrey camera which model number is FL3-U3-32S2M-CS used in this application example, the electron well depth is 10066.31. Therefore, the highest phase sensitivity of this system herein corresponds to 0.00997 rad. If the OPD is used to characterize noise, it should be 0.84 nm.
In the experimental setup of this application example, by using our design of an optical fiber-based portable interferometer, the phase noise caused by mechanical vibration is expected to be minimized as the travel distance of the beam in the air is significantly reduced. In this application example, the system phase noise characteristics in the absence of a sample are measured, and 300 interferograms are obtained at 60 fps and their corresponding OPDs are retrieved. The result shows that the spatial phase noise histogram which exhibits a Gaussian-like profile and has a standard deviation of 0.76 nm as the spatial noise and the temporal phase noise histogram with a 0.99 nm median value as the temporal phase noise under 532 nm illumination. In summary, the result of 0.99 nm is very close to the minimum noise value, and this system achieves comparable nanoscale phase sensitivity to previously reported in laser-based QPM systems.
According to the Abbe criterion, the lateral resolution of the imaging system of this application example with green light is λ/NA≈0.82 μm (or full-pitch resolution). To further validate the resolution of the system, we have measured the phase resolution target (Quantitative Phase Microscope Target (QPT), Benchmark Technologies Corporation, U.S.).
This part will prove the dispersion characterization capability proposed in the system using this application example. First, this application example tests the phase and height imaging performance and refractive index contrast by measuring calibration samples. In this application example, the sample for testing is 50 μm microbeads and fluorescent particles, and the microbead samples for measurement are Thermo 4205A microbeads with a diameter of 50 μm. These polystyrene beads (with a refractive index of 1.59) are suspended in a index matching liquid (with a refractive index of 1.57). From the system, the two phase maps retrieved from two different wavelengths, containing one bead, can be shown in
Monodisperse fluorescent microspheres are prepared by combining fluorescent molecules on the matrix or surface of polystyrene microspheres. Fluorescent microspheres have the characteristics of high fluorescence intensity and strong dispersion properties. Its maximum excitation wavelength is 620 nm, and its maximum emission wavelength is 680 nm. It can be proved that in the system of this application example, there is a significant difference in the absorption of the two wavelengths of 633 nm and 532 nm by the fluorescent particles. This also demonstrates the same theory as reported in our experimental results. From the phase maps obtained in
Many types of molecules can be distinguished by their dispersion. For example, hemoglobin (Hb) has obvious dispersion at the wavelength of visible light, so the distribution and concentration of hemoglobin in red blood cells (RBC) can be calculated by measuring its dispersion characteristics. The system based on this application example can demonstrate the simultaneous extraction of cell membrane fluctuations and the dispersion characteristics of a single complete RBC via the wavelength-dependent refractive index measurements.
Then, we further calculate the refractive index of the selected cells and calculate the hemoglobin concentration. The model provided in this application example reveals the relationship between hemoglobin concentration and phase measurement as follows:
The system in this application example provides two light sources with different wavelengths, which can also be used for fluorescence imaging and phase imaging with the same camera. To illustrate the combined phase-fluorescence imaging capability, this application example conducts both phase measurements and fluorescence imaging experiments on commercially available standard fluorescent particles and Mouse Embryonic Fibroblast Cells (NIH 3T3). The results are shown in
The standard fluorescent particles made of polystyrene have been coated with Nile Blue dye on the surface. Its maximum excitation wavelength is 620 nm, and its maximum emission wavelength is 680 nm. In this application example, a 633 nm light source is selected for excitation, and a long-wavelength band-pass filter with a cut-off wavelength of 650 nm is placed in front of the camera lens. On the other hand, the 532 nm light source is used for quantitative phase imaging, and the topography information can be analyzed as the experimental results shown in FIGS. 7A to 7C, which agree with the manufacturer's size. Researches have shown that this fluorescent dye can bind to lipid molecules and is usually used to reveal cell membranes and other biological membranes. Further this fluorescent dye can also be used to stain biological cells. Before imaging, the NIH 3T3 cells were processed by staining treatment with 0.1 mg/ml Nile Blue Sulfate for 8 minutes. Then the cells were imaged directly in culture dish, surrounded by the culture medium. The quantitative phase image of dye-stained cells is shown in
In quantitative phase imaging, for an object or sample with an optical depth greater than the wavelength of the illumination, the phase image contains 2π discontinuities. However, most of the existing phase unwrapping algorithms used to eliminate discontinuities require subjective intervention, such as the Goldstein phase unwrapping algorithm. Here, this application example proposes a measurement method to physically solve the problem of discontinuous phase measurement results obtained when there are height steps on the object that are greater than the wavelength of the illumination. In the M2QPM system, the dual-wavelength phase retrieval method simplifies the image processing process and expands the clear phase range by processing two phase profiles and creating a phase profile corresponding to the synthetic wavelength, which is much longer than any wavelength of light used in the experiment. This method has the ability to maintain high phase sensitivity and stability while measuring 3D contours of samples up to tens of microns that cannot be measured by single-wavelength illumination. In the experiment, the accuracy of the phase unwrapping method based on multi-wavelength testing and synthetic wavelength guidance was verified by measuring 50 μm standard beads, and further compared with the classic phase unwrapping algorithm. Specifically, imaging applications are performed on steep and optically thick structures such as channel structures on microfluidic chips.
In the experiment, the center wavelengths of the two lasers are λ1=633 nm and λ2=532 nm, respectively. For testing with samples, the phase maps extracted for each wavelength channel are φ1(x,y) and φ2(x,y). According to the following equation (1), the synthetic wavelength can be obtained:
The resulting synthetic wavelength Λ=3334.2 nm. Subtract the phases of these two wavelength channels to obtain the phase map corresponding to the combined wavelength:
After subtraction, there may be some phase jumps due to the wrapping mismatch between these two wrapped phase maps corresponding to the two wavelengths. When the difference is negative, the mismatching problem can be solved by adding a period of 2π. In this case, the sample height can be calculated by the following formula:
The two-wavelength phase retrieval and unwrapping process is shown in
In single-wavelength phase images, the phase unwrapping process usually uses conventional algorithms, which may cause problems. A typical software unwrapping algorithm starts at a specific point in the image and moves along a one-dimensional path (for example, a straight line, a spiral). If it encounters something that looks like a phase wrap, the phase is shifted down or up by 2π. When the phase change caused by the real sample structure is greater than 2×, the phase change is discontinuous at this time, and the traditional unwrapping algorithm based on step iteration will obviously cause errors. Exemplarily, in order to test this type of structure, this application example provides a 5 μm high PDMS microchannel, and the physical image is shown in
This application example proposes and demonstrates a new type of portable multi-modal and multi-wavelength fiber-based quantitative phase microscope (M2QPM), in which the interferometric measurement is realized by tuning the optical path length of the reference beam through a single-mode optical fiber. In this setup, the light mainly propagates in the coiled optical fibers instead of free space, which can achieve a compact size and high sensitivity. With fiber couplers and fiber combiners, the system are able to simultaneously illuminate the sample with two different wavelengths of light and obtain their interferograms in a single acquisition. Since the sample information corresponding to the light of two different wavelengths does not overlap in the spatial frequency space, the phase map of each wavelength channel can be fully reconstructed based on the interferogram obtained by the system. Based on the retrieved phase map, this application example can explore various applications, such as detecting the dispersion properties of dispersive samples, showing multi-modal quantitative phase and fluorescence images, and characterizing optically thick structures.
According to the embodiments of the disclosure herein, the disclosure herein also provides a readable storage medium and a computer program product.
Various implementations of the systems and technologies described in this article can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGA), application specific integrated circuits (ASIC), application-specific standard products (ASSP), system-on-chip SOC, load programmable logic device (CPLD), computer hardware, firmware, software, and/or their combination. These various embodiments may include: being implemented in one or more computer programs, the one or more computer programs may be executed and/or interpreted on a programmable system including at least one programmable processor, the programmable processor It can be a dedicated or general-purpose programmable processor that can receive data and instructions from the storage system, at least one input device, and at least one output device, and transmit the data and instructions to the storage system, the at least one input device, and the at least one output device. An output device.
The program code used to implement the method of the disclosure herein can be written in any combination of one or more programming languages. These program codes can be provided to the processors or controllers of general-purpose computers, special-purpose computers, or other programmable data processing devices, so that when the program codes are executed by the processors or controllers, the functions specified in the flowcharts and/or block diagrams/The operation is implemented. The program code can be executed entirely on the machine, partly executed on the machine, partly executed on the machine and partly executed on the remote machine as an independent software package, or entirely executed on the remote machine or server.
It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the disclosure herein can be executed in parallel, sequentially, or in a different order, as long as the desired result of the technical solution disclosed in the disclosure herein can be achieved, this is not limited herein.
The foregoing specific implementations do not constitute a limitation on the protection scope of the disclosure herein. Those skilled in the art should understand that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent replacement and improvement made within the spirit and principle of the disclosure herein shall be included in the protection scope of the disclosure herein.
This application is a continuation of the U.S. application Ser. No. 17/454,461 filed on 10 Nov. 2021, and entitled “Device, Method and Computer Readable Storage Medium for Quantitative Phase Imaging”.
Number | Date | Country | |
---|---|---|---|
Parent | 17454461 | Nov 2021 | US |
Child | 18801596 | US |