CN220289403U - Multispectral space frequency domain imaging device based on white light LED - Google Patents
Multispectral space frequency domain imaging device based on white light LED Download PDFInfo
- Publication number
- CN220289403U CN220289403U CN202223228587.0U CN202223228587U CN220289403U CN 220289403 U CN220289403 U CN 220289403U CN 202223228587 U CN202223228587 U CN 202223228587U CN 220289403 U CN220289403 U CN 220289403U
- Authority
- CN
- China
- Prior art keywords
- liquid crystal
- polaroid
- tunable filter
- white light
- crystal tunable
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000003384 imaging method Methods 0.000 title claims abstract description 40
- 239000004973 liquid crystal related substance Substances 0.000 claims abstract description 29
- 230000005540 biological transmission Effects 0.000 claims description 3
- 230000010287 polarization Effects 0.000 claims 1
- 230000003287 optical effect Effects 0.000 abstract description 10
- 238000001228 spectrum Methods 0.000 abstract description 7
- 238000003745 diagnosis Methods 0.000 abstract description 4
- 230000010354 integration Effects 0.000 abstract description 4
- 238000000034 method Methods 0.000 description 11
- INGWEZCOABYORO-UHFFFAOYSA-N 2-(furan-2-yl)-7-methyl-1h-1,8-naphthyridin-4-one Chemical compound N=1C2=NC(C)=CC=C2C(O)=CC=1C1=CC=CO1 INGWEZCOABYORO-UHFFFAOYSA-N 0.000 description 5
- 108010064719 Oxyhemoglobins Proteins 0.000 description 5
- 108010002255 deoxyhemoglobin Proteins 0.000 description 5
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 4
- 239000008280 blood Substances 0.000 description 4
- 210000004369 blood Anatomy 0.000 description 4
- 229910052760 oxygen Inorganic materials 0.000 description 4
- 239000001301 oxygen Substances 0.000 description 4
- 238000000342 Monte Carlo simulation Methods 0.000 description 3
- 238000010521 absorption reaction Methods 0.000 description 3
- 230000008033 biological extinction Effects 0.000 description 2
- 238000004422 calculation algorithm Methods 0.000 description 2
- 238000004364 calculation method Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- KXRMREPJUITWDU-UHFFFAOYSA-N 2-amino-4,6-dimethyl-3-oxophenoxazine-1,9-dicarboxylic acid Chemical compound N1=C2C(C(O)=O)=C(N)C(=O)C(C)=C2OC2=C1C(C(O)=O)=CC=C2C KXRMREPJUITWDU-UHFFFAOYSA-N 0.000 description 1
- 208000008960 Diabetic foot Diseases 0.000 description 1
- 108010061951 Methemoglobin Proteins 0.000 description 1
- 206010052428 Wound Diseases 0.000 description 1
- 208000027418 Wounds and injury Diseases 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000017531 blood circulation Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 201000010099 disease Diseases 0.000 description 1
- 208000037265 diseases, disorders, signs and symptoms Diseases 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 238000005286 illumination Methods 0.000 description 1
- 238000012634 optical imaging Methods 0.000 description 1
- 230000010363 phase shift Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000002310 reflectometry Methods 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
The utility model discloses a multispectral space frequency domain imaging device based on a white light LED, which comprises a white light LED, a digital micromirror device, a projection lens, a first polaroid, a sample to be tested, a second polaroid, a liquid crystal tunable filter, an imaging lens, a CMOS camera and a computer; the white light emitted by the white light LED passes through the digital micromirror device to generate a stripe image with specific spatial frequency, the stripe image is projected to a sample to be detected through the projection lens and the first polaroid to generate a diffuse reflection light signal, the diffuse reflection light signal sequentially passes through the second polaroid and the liquid crystal tunable filter, and the diffuse reflection light signal passing through the liquid crystal tunable filter is incident on the target surface of the CMOS camera after passing through the imaging lens and then is transmitted into the computer to complete the acquisition of image information. The system can realize diffuse reflection light image acquisition of biological tissue bodies in different wave bands, has the advantages of more spectrum information, small volume, convenient integration and the like, and has wide application prospect in personalized optical diagnosis and treatment.
Description
Technical Field
The utility model relates to the technical field of space frequency domain imaging, in particular to a multispectral space frequency domain imaging device based on a white light LED.
Background
The space frequency domain imaging (Spatial Frequency Domain Imaging, SFDI) is a non-contact wide-field optical imaging technology, which adopts structural light with a certain space frequency to irradiate a biological tissue body, collects diffuse reflection light generated by the biological tissue body, demodulates the diffuse reflection light through algorithms such as three phase shifts and the like, adopts a table look-up method and the like, and obtains the two-dimensional distribution of optical characteristic parameters of the surface of the biological tissue in an inversion way. If the illumination is performed by using the structured light with a plurality of wavelengths, multispectral space frequency domain imaging can be realized. The multispectral space frequency domain imaging can quantitatively obtain information of oxyhemoglobin, deoxyhemoglobin, methemoglobin, water, fat and other components from a biological tissue sample in a space resolution mode on the basis of quantitatively obtaining optical characteristic parameters of the biological tissue body tissue, and can be used for clinically evaluating diseases such as burn wounds, diabetic foot ulcers and the like.
The prior spatial frequency domain imaging system adopts a DLP light engine as a light source, can only realize spatial frequency domain imaging with three wavelengths, and is insufficient for obtaining rich biological tissue related information. In order to increase the spectrum content, a scheme of combining a plurality of discrete light sources is often adopted, for example, a plurality of LEDs with different wavelengths are combined with an external digital micromirror device or other modulation devices to generate structural light with a plurality of wavelengths, the method tends to increase the volume and the construction complexity of a system, the collection speed is limited by the wavelength switching speed, and the number of the collected spectrums is very limited. In addition, researchers obtain wavelength tuning by combining a supercontinuum laser with slit scanning, and can acquire images with up to one thousand wavelengths, but because an input light beam needs to pass through a plurality of lenses, the luminous flux is greatly reduced, and the light source has high cost and large volume and is inconvenient to integrate. Aiming at the problems, the utility model provides a multispectral space frequency domain imaging system which takes a white light LED as a light source and adopts a liquid crystal tunable filter to realize spectrum selection, and the system has the advantages of small volume, simple structure, convenient integration and the like, can quantitatively obtain the information of tissue components, optical characteristic parameters, blood flow dynamics, microvascular functions and the like in biological tissue samples, and has wide application prospect in personalized optical diagnosis and treatment.
Disclosure of Invention
The utility model aims to provide a multispectral space frequency domain imaging device based on a white light LED.
The technical scheme adopted by the utility model is as follows:
a multispectral space frequency domain imaging device based on a white light LED comprises the white light LED, a digital micromirror device, a projection lens, a first polaroid, a sample to be tested, a second polaroid, a liquid crystal tunable filter, an imaging lens, a CMOS camera and a computer; white light emitted by a white light LED passes through a digital micromirror device to generate a sine gray image with specific spatial frequency, the sine gray image is projected to a sample to be detected through a projection lens and a first polaroid to generate a diffuse reflection light signal, the diffuse reflection light signal passes through a second polaroid and then enters a liquid crystal tunable filter, the liquid crystal tunable filter only allows the diffuse reflection light signal with specific wavelength to pass through under a computer control instruction, the diffuse reflection light signal passing through the liquid crystal tunable filter passes through an imaging lens and then enters a CMOS camera target surface, and the CMOS camera transmits acquired image information into a computer to complete acquisition of the image information; the wavelength of the light passing through the liquid crystal tunable filter is controlled to be changed through computer instructions, and the operation is repeated to obtain a multispectral diffuse reflection light image.
Further, the wavelength of the white light LED is 400nm-720nm.
Furthermore, the micro-mirror on the digital micro-mirror device can be loaded with the image with specific spatial frequency generated by computer processing under the action of an electronic switch.
Furthermore, the white light LED, the digital micro-mirror device and the projection lens are fixedly arranged right above the sample to be tested by using the mounting bracket.
Further, the first polaroid is arranged at the front end of the projection lens through a bracket; the second polaroid is arranged at the front end of the liquid crystal tunable filter in a threaded manner. The transmission directions of the first polaroid and the second polaroid are mutually perpendicular.
Furthermore, the wavelength range of the light passing through of the liquid crystal tunable filter is 400nm-720nm, and the wavelength of the light passing through can be rapidly switched under the control of a computer.
Furthermore, the liquid crystal tunable filter, the imaging lens and the CMOS camera are connected through threads of all the components and are fixed right above a sample to be detected by using a mounting bracket.
Furthermore, the white light LED, the digital micro-mirror device and the projection lens are packaged by mechanical parts, are fixed right above a sample to be tested by using a mounting bracket, are parallel to the imaging lens, and have a distance smaller than 5mm with the liquid crystal tunable filter.
By adopting the technical scheme, the diffuse reflection light image acquisition of biological tissue bodies with different wave bands can be realized, and the method has the advantages of multiple spectrum information, small volume, convenience in integration and the like, and has wide application prospects in personalized optical diagnosis and treatment.
Drawings
The utility model is described in further detail below with reference to the drawings and detailed description;
FIG. 1 is a schematic diagram of a multi-spectral spatial frequency domain imaging system based on white light LEDs according to the present utility model;
fig. 2 is a flow chart of a method for implementing a white light LED-based multispectral spatial frequency domain imaging system of the present utility model.
In the figure: 1-white light LED, 2-digital micro-mirror device, 3-projection lens, 4-first polarizer, 5-sample to be tested, 6-second polarizer, 7-liquid crystal tunable filter, 8-imaging lens, 9-CMOS camera, 10-computer.
Detailed Description
For the purposes, technical solutions and advantages of the embodiments of the present application, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application.
As shown in fig. 1, the present utility model provides a white light LED-based multispectral space frequency domain imaging system, which comprises a white light LED1, a digital micromirror device 2, a projection lens 3, a first polarizer 4, a sample 5 to be tested, a second polarizer 6, a liquid crystal tunable filter 7, an imaging lens 8, a CMOS camera 9 and an imaging computer 10. The white light LED1 emits light to the digital micro-mirror device 2, the computer 10 controls the digital micro-mirror device 2 to generate a three-phase sine gray level image with specific spatial frequency through instructions, the generated sine fringe image with specific spatial frequency is projected onto a sample 5 to be detected through the projection lens 3, diffuse reflection light generated by the sample 5 to be detected enters the liquid crystal tunable filter 7 through the second polarizer 6, the imaging lens 8 and the CMOS camera 9 complete collection of diffuse reflection light images of biological tissue, the light wavelength of the liquid crystal tunable filter 7 is changed, diffuse reflection light image collection is repeatedly performed to obtain a plurality of spectrum image information, the collected image information is transmitted into the computer 10, the three-phase shift method is adopted for image demodulation, and the optical characteristic parameters, the oxyhemoglobin concentration, the deoxyhemoglobin concentration and the blood oxygen saturation of the biological tissue are obtained through a table look-up method or a reverse Monte Carlo simulation method.
Referring to fig. 1 and fig. 2, after the multispectral space frequency domain imaging system based on the white light LED is built, the specific implementation manner of the embodiment is as follows:
step 1: placing the system in a darkroom, opening a CMOS camera (MV-CA 013-AOUM, haikang Wei, china), and collecting darkfield image information;
step 2: turning on white light LEDs (MCWHL 8-C1, thorlabs, USA), taking a checkerboard (0.5 mm multiplied by 0.5 mm) as a sample to be tested, projecting a uniform white light image on the checkerboard through a digital micromirror device (LC 4500-NIR-EKT, keynote Photonics, USA), acquiring the checkerboard image by a CMOS camera, and obtaining the number of pixels corresponding to a pair of black and white squares from the checkerboard image;
step 3: taking down the checkerboard, taking the diffuse reflectance board as a sample to be measured, adjusting the height of the diffuse reflectance board to enable the surface of the diffuse reflectance board to be the same as the surface of the checkerboard in the step 2, and generating a square wave fringe image by adopting MATLAB programming software, wherein the space period of the square wave image is consistent with the linear degree corresponding to a pair of black and white squares of the checkerboard. The digital micro-mirror device is controlled by a computer instruction to generate square wave structured light and project the square wave structured light to the diffuse reflection plate, the CMOS camera collects stripe images reflected by the diffuse reflection plate, the number of pixels corresponding to one stripe period is obtained from the stripe images, the ratio calculation is carried out on the number of pixels corresponding to one square of the checkerboard image obtained in the step 2, the correction coefficient of the space frequency is obtained, and three-phase sine images with different space frequencies are generated through MATLAB programming software according to the correction coefficient;
step 4: the standard sample with known optical characteristic parameters is adopted, and the standard sample is obtained at each wavelength lambda through calculation of a Monte Carlo simulation algorithm 1 、λ 2 、…λ i Zero frequency (f) x =0) diffuse reflectance R DC，ref And high frequency (f x ＝0.1mm -1 ) Diffuse reflectance R AC，ref ；
Step 5: taking down the diffuse reflectance plate, placing a standard sample, adjusting the position of the standard sample to ensure that the surface of the standard sample is consistent with the height of the surface of the checkerboard in the step 2, and generating zero frequency (f) through a digital micromirror device x ＝0mm -1 ) Three-phase (0, 2 pi/3, 4 pi/3) images are sequentially projected onto the surface of a standard sample, and a computer-controlled liquid crystal tunable filter (VariSpec VIS, perkinElmer, USA) selects the wavelength lambda of light passing through 1 Synchronous acquisition lambda of CMOS camera 1 Three-phase sinogram I with wavelength at zero frequency 10 ，I 20 And I 30 Calculating according to formula (1) to obtain the standard sample at wavelength lambda 1 Lower DC amplitude M DC，ref ：
Step 6: maintaining control of the wavelength lambda of the light passing through the liquid crystal tunable filter 1 High frequency (f x ＝0.1mm -1 ) Three-phase (0, 2 pi/3, 4 pi/3) sinusoidal images of the standard sample are projected to the surface of the standard sample in sequence, and the CMOS camera is the same as the CMOS cameraStep acquisition lambda 1 Three-phase sinogram I at high wavelength frequency 1 ，I 2 And I 3 Calculating according to formula (2) to obtain the standard sample at wavelength lambda 1 Ac amplitude M AC，ref ：
Step 7: taking down the standard sample, placing the biological tissue body to be detected on the standard sample, repeating the step 5 and the step 6 to obtain the biological tissue body at lambda 1 M at wavelength DC，sample And M AC，sample ；
Step 8: obtaining the real reflectivity R of the biological tissue body to be detected after calibration according to the formula (3) and the formula (4) DC，sample And R is AC，sample Inversion of optical characteristic parameters is carried out through a reverse Monte Carlo simulation method or a table look-up method, and the biological tissue body at lambda is obtained 1 Absorption coefficient at wavelength:
step 9: control the liquid crystal tunable filter to sequentially switch its light wavelength to lambda 2 、…λ i Then, repeating the steps 5, 6, 7 and 8 to obtain the biological tissue body at lambda 2 、…λ i Absorption coefficient at wavelength;
step 10: based on the molar extinction coefficient epsilon of chromophores such as oxyhemoglobin and deoxyhemoglobin i (λ i ) Performing least squares fitting on the formula (5) to obtain the concentration C of the chromophores such as oxyhemoglobin and deoxyhemoglobin i ：
Wherein mu a (λ i ) Is of wavelength lambda i When the biological tissue to be measured is in the process, the absorption coefficient epsilon i (λ i ) At wavelength lambda for the ith chromophore i Molar extinction coefficient at time, C i Concentration of the ith chromophore;
and then calculating according to a formula (6) to obtain the blood oxygen saturation of the biological tissue body:
wherein StO is 2 Is the blood oxygen saturation, C (HbO) 2 ) Represents the concentration of oxyhemoglobin, and C (Hb) represents the concentration of deoxyhemoglobin.
Through the steps, the multispectral space frequency domain imaging technology based on the white light LED can be applied to complete the acquisition of the blood oxygen saturation of the biological tissue.
By adopting the technical scheme, the diffuse reflection light image acquisition of biological tissue bodies with different wave bands can be realized, and the method has the advantages of multiple spectrum information, small volume, convenience in integration and the like, and has wide application prospects in personalized optical diagnosis and treatment.
It will be apparent that the embodiments described are some, but not all, of the embodiments of the present application. Embodiments and features of embodiments in this application may be combined with each other without conflict. The components of the embodiments of the present application, which are generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations. Thus, the detailed description of the embodiments of the present application is not intended to limit the scope of the application, as claimed, but is merely representative of selected embodiments of the application. All other embodiments, which can be made by one of ordinary skill in the art based on the embodiments herein without making any inventive effort, are intended to be within the scope of the present application.
Claims (7)
1. A multispectral space frequency domain imaging device based on white light LED is characterized in that: the device comprises a white light LED, a digital micromirror device, a projection lens, a first polaroid, a sample to be tested, a second polaroid, a liquid crystal tunable filter, an imaging lens, a CMOS camera and a computer; the white light LED emits white light to irradiate the digital micro-mirror device, the digital micro-mirror device is controlled by a computer to generate a stripe image with specific spatial frequency, the stripe image is projected to a sample to be detected through a projection lens and a first polaroid to generate a diffuse reflection light signal, the diffuse reflection light signal enters a liquid crystal tunable filter after passing through a second polaroid, the computer sends a control command to control the wavelength of light passing through the liquid crystal tunable filter, and then the imaging lens and the CMOS camera are used for completing acquisition of a plurality of frequency three-phase image under the wavelength; the wavelength of the light passing through the liquid crystal tunable filter is controlled to be changed through computer instructions, and the operation is repeated to obtain a multispectral diffuse reflection light image.
2. A white LED-based multispectral spatial frequency domain imaging device according to claim 1, wherein: the wavelength of the white light LED is 400nm-720nm.
3. A white LED-based multispectral spatial frequency domain imaging device according to claim 1, wherein: the white light LED, the digital micro-mirror device and the projection lens are fixedly arranged right above a sample to be tested by using the mounting bracket.
4. A white LED-based multispectral spatial frequency domain imaging device according to claim 1, wherein: the first polaroid is arranged at the front end of the emergent light of the projection lens through a bracket; the second polaroid is arranged at the front end of the liquid crystal tunable filter through threads on the liquid crystal tunable filter, and the polarization directions of the first polaroid and the second polaroid are mutually perpendicular.
5. A white LED-based multispectral spatial frequency domain imaging device according to claim 1, wherein: the white light LED, the digital micro-mirror device and the projection lens are packaged by mechanical parts, are fixed right above a sample to be tested by using a mounting bracket, are parallel to the imaging lens, and have a distance of less than 5mm with the liquid crystal tunable filter.
6. A white LED-based multispectral spatial frequency domain imaging device according to claim 1, wherein: the liquid crystal tunable filter, the imaging lens and the CMOS camera are connected through threads of all the components and are fixedly arranged right above a sample to be tested by using the mounting bracket.
7. A white LED-based multispectral spatial frequency domain imaging device according to claim 1, wherein: the light transmission range of the liquid crystal tunable filter is 400-720nm, and the wavelength of the light transmission is rapidly switched by computer control.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202223228587.0U CN220289403U (en) | 2022-12-02 | 2022-12-02 | Multispectral space frequency domain imaging device based on white light LED |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202223228587.0U CN220289403U (en) | 2022-12-02 | 2022-12-02 | Multispectral space frequency domain imaging device based on white light LED |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN220289403U true CN220289403U (en) | 2024-01-02 |
Family
ID=89336998
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202223228587.0U Active CN220289403U (en) | 2022-12-02 | 2022-12-02 | Multispectral space frequency domain imaging device based on white light LED |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN220289403U (en) |
-
2022
- 2022-12-02 CN CN202223228587.0U patent/CN220289403U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR102251749B1 (en) | Efficient modulated imaging | |
| Gioux et al. | Three-dimensional surface profile intensity correction for spatially modulated imaging | |
| JP4891261B2 (en) | Optical image measuring device | |
| Applegate et al. | OpenSFDI: an open-source guide for constructing a spatial frequency domain imaging system | |
| US20160270665A1 (en) | Method and apparatus for imaging tissue topography | |
| JP6353145B2 (en) | Tissue oxygenation measurement system and method | |
| JPWO2012011246A1 (en) | Image processing device | |
| GB2429385A (en) | Image processing method and apparatus | |
| US10470694B2 (en) | Systems and methods for measuring tissue oxygenation | |
| WO2015143417A1 (en) | Systems and methods for measuring tissue oxygenation | |
| US20160091707A1 (en) | Microscope system for surgery | |
| WO2018229834A1 (en) | Endoscope system | |
| WO2018229832A1 (en) | Endoscope system | |
| JP2021536274A (en) | Hyperspectral device and method | |
| Rogelj et al. | Effect of curvature correction on parameters extracted from hyperspectral images | |
| CN220289403U (en) | Multispectral space frequency domain imaging device based on white light LED | |
| CN112203572A (en) | Endoscope system | |
| Ipus et al. | Single-pixel imaging through non-homogeneous turbid media with adaptive illumination | |
| Federici et al. | Noninvasive light-reflection technique for measuring soft-tissue stretch | |
| Feng et al. | Motion-resistant three-wavelength spatial frequency domain imaging system with ambient light suppression using an 8-tap CMOS image sensor | |
| CN218572188U (en) | Laser speckle blood flow imaging system | |
| CN118490201A (en) | Structured light projection device, imaging device, detection method and detection equipment for biological tissue physiological parameter measurement | |
| JP2013052182A (en) | Method for measuring cutaneous pigment concentration | |
| CN115931780A (en) | Quantitative detection device and method for blood oxygen saturation spatial distribution in photodynamic therapy | |
| JP2018054450A (en) | Reflection spectrum measurement method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |