Abstract: A single-shot differential phase contrast quantitative phase imaging method based on color multiplexing illumination. A color multiplexing illumination solution is used to realize single-shot differential phase contrast quantitative phase imaging. In the single-shot color multiplexing illumination solution, three illumination wavelengths of red, green, and blue are used to simultaneously illuminate a sample, and the information of the sample in multiple directions is converted into intensity information on different channels of a color image. By performing channel separation on this color image, the information about the sample at different spatial frequencies can be obtained.

Abstract: The invention discloses a three-dimensional (3D) measurement method based on end-to-end deep learning for speckle projection. First, the speckle pattern was projected by the projector and collected simultaneously by the stereo camera. The speckle images after stereo rectification are fed into the stereo matching network. A feature extraction sub-network based on shared weights processes the speckle images to obtain a series of low-resolution 3D feature tensors, The feature tensor is fed into the saliency object detection sub-network to detect foreground information in the speckle images, producing a full-resolution valid mask map. A 4D matching cost volume is generated using the feature tensor of both views based on the candidate disparity range, filtered by a series of 3D convolutional layers to achieve cost aggregation, so that the initial disparity map is obtained by disparity regression.

Abstract: The invention discloses a miniaturized, low-cost, multi-contrast label-free microscopic imaging system. The imaging system is based on an inverted microscopic structure, a highly integrated optical system is designed by adopting a micro lens having a fixed focal length, and a complex optical system of a traditional microscope system is replaced, such that the whole microscope is highly integrated. The system uses a programmable LED array as an illumination light source the LED array is controlled by a computer to display different illumination modes, six imaging functions of a bright field, a dark field a rainbow dark field, Rheinberg optical dyeing, differential phase contrast, and quantitative phase imaging are achieved; and diversified unmarked imaging methods are provided for biological applications.

Abstract: A calibration method for fringe projection systems based on plane mirrors. Firstly, two mirrors are placed behind the tested object. Through the reflection of mirrors, the camera can image the measured object from the front and other two perspectives, so as to obtain 360-degree two-dimensional information of the measured object. The projector projects three sets of phase-shifting fringe patterns with frequencies of 1, 8, and 64. The camera captures the fringe image to obtain an absolute phase map with a frequency of 64 by using the phase-shifting method and the temporal phase unwrapping algorithm. By using the calibration parameters between the projector and the camera, the absolute phase map can be converted into three-dimensional information of the measured object. Then, the mirror calibration is realized by capturing a set of 3D feature point pairs, so that the 3D information from different perspectives is transformed into a unified world coordinate system.

Abstract: The present invention discloses a three-dimensional diffraction tomography microscopy imaging method based on LED array coded illumination. Firstly, acquiring the raw intensity images, three sets of intensity image stacks are acquired at different out-of-focus positions by moving the stage or using electrically tunable lens. And then, after acquiring the intensity image stacks of the object to be measured at different out-of-focus positions, the three-dimensional phase transfer function of the microscopy imaging system with arbitrary shape illumination is derived. Further, the three-dimensional phase transfer function of the microscopic system under circular and annular illumination with different coherence coefficients is obtained as well, and the three-dimensional quantitative refractive index is reconstructed by inverse Fourier transform of the three-dimensional scattering potential function. The scattering potential function is converted into the refractive index distribution.

Abstract: A microscopic imaging method of phase contrast (PC) and differential interference contrast (DIC) based on the transport of intensity equation (TIE) includes capturing three intensity images along the optical axis; solving the TIE by deconvolution to obtain the quantitative phase; obtaining the intensity image under the DIC imaging mode according to the DIC imaging principle; and obtaining the corresponding phase image of PC imaging mode according to the PC imaging principle. The method can endow the bright-field microscope with the ability to realize PC and DIC imaging without complex modification of the traditional bright-field microscope. In addition, it has the same imaging performance as the phase contrast microscope and differential interference contrast microscope, which are expensive, complex-structure, and has strict environmental conditions.

Abstract: The invention discloses a single-frame fringe pattern analysis method based on multi-scale generative adversarial network. A multi-scale generative adversarial neural network model is constructed and a comprehensive loss function is applied. Next, training data are collected to train the multi-scale generative adversarial network. During the prediction, a fringe pattern is fed into the trained multi-scale network where the generator outputs the sine term, cosine term, and the modulation image of the input pattern. Finally, the arctangent function is applied to compute the phase. When the network is trained, the parameters of the network do not need to manually tune during the calculation. Since the input of the neural network is only a single fringe pattern, the invention provides an efficient and high-precision phase calculation method for moving objects.

Abstract: The invention discloses a programmable annular LED illumination-based high efficiency quantitative phase microscopy imaging method, the proposed method comprising the following steps: the derivation of system optical transfer function in a partially coherent illumination imaging system; the derivation of phase transfer function with the weak object approximation under the illumination of tilted axially symmetric coherent point illumination source; the extension of illumination from an axially symmetric coherence point source to a discrete annular point source, and the optical transfer function can be treated as an incoherent superposition of each pair of tilted axially symmetric coherent point sources. The acquisition of raw intensity dataset; the implementation of deconvolution for quantitative phase reconstruction.

Abstract: A single-shot differential phase contrast quantitative phase imaging method based on color multiplexing illumination. A color multiplexing illumination solution is used to realize single-shot differential phase contrast quantitative phase imaging. In the single-shot color multiplexing illumination solution, three illumination wavelengths of red, green, and blue are used to simultaneously illuminate a sample, and the information of the sample in multiple directions is converted into intensity information on different channels of a color image. By performing channel separation on this color image, the information about the sample at different spatial frequencies can be obtained.

Abstract: The patent discloses a differential phase contrast (DPC) quantitative phase microscopy method based on the optimal illumination pattern design. Firstly, the optimal illumination pattern corresponding to the isotropic phase transfer function of DPC quantitative phase imaging is derived, which is determined as a semi-annular illumination pattern with the illumination numerical aperture NAill equal to the numerical aperture NAobj of the objective lens. The illumination intensity distribution varies with the cosine of the illumination angle, and it can be expressed as S(?)=cos(?). This patent effectively compensates for the frequency loss of phase transfer, not only the high-frequency responses of PTF are enhanced, but also the transfer responses of low-frequency phase information is significantly improved.

Abstract: A calibration method for fringe projection systems based on plane mirrors. Firstly, two mirrors are placed behind the tested object. Through the reflection of mirrors, the camera can image the measured object from the front and other two perspectives, so as to obtain 360-degree two-dimensional information of the measured object. The projector projects three sets of phase-shifting fringe patterns with frequencies of 1, 8, and 64. The camera captures the fringe image to obtain an absolute phase map with a frequency of 64 by using the phase-shifting method and the temporal phase unwrapping algorithm. By using the calibration parameters between the projector and the camera, the absolute phase map can be converted into three-dimensional information of the measured object. Then, the mirror calibration is realized by capturing a set of 3D feature point pairs, so that the 3D information from different perspectives is transformed into a unified world coordinate system.

Abstract: The invention claims a microscopic imaging method of phase contrast (PC) and differential interference contrast (DIC) based on the transport of intensity equation (TIE). Firstly, three intensity images are captured along the optical axis; secondly, TIE is solved by deconvolution to obtain the quantitative phase; then, the intensity image under the DIC imaging mode is obtained according to the DIC imaging principle; finally, the corresponding phase image of PC imaging mode is obtained according to the PC imaging principle. The proposed approach can endow the bright-field microscope with the ability to realize PC and DIC imaging without complex modification of the traditional bright-field microscope. In other words, this method only needs to use the traditional bright-field microscope without adding any complex hardware. Through the PC and DIC algorithms, this method has the advantages of quantitative, high-speed, low-cost, simple structure, and less external interference.

Abstract: The present invention discloses a three-dimensional diffraction tomography microscopy imaging method based on LED array coded illumination. Firstly, acquiring the raw intensity images, three sets of intensity image stacks are acquired at different out-of-focus positions by moving the stage or using electrically tunable lens. And then, after acquiring the intensity image stacks of the object to be measured at different out-of-focus positions, the three-dimensional phase transfer function of the microscopy imaging system with arbitrary shape illumination is derived. Further, the three-dimensional phase transfer function of the microscopic system under circular and annular illumination with different coherence coefficients is obtained as well, and the three-dimensional quantitative refractive index is reconstructed by inverse Fourier transform of the three-dimensional scattering potential function. The scattering potential function is converted into the refractive index distribution.

Abstract: A high-illumination numerical aperture-based large field-of-view high-resolution microimaging device, and a method for iterative reconstruction, the device comprising an LED array (1), a stage (2), a condenser (3), a microscopic objective (5), a tube lens (6), and a camera (7), the LED array (1) being arranged on the forward focal plane of the condenser (3). Light emitted by the i-th lit LED unit (8) of the LED array (1) passes through the condenser (3) and converges to become parallel light illuminating a specimen (4) to be examined, which is placed on the stage (2); part of the diffracted light passing through the specimen (4) is collected by the microscopic objective (5), converged by the tube lens (6), and reaches the imaging plane of the camera (7), forming an intensity image recorded by the camera (1). The present device and method ensure controllable programming of the illumination direction, while also ensuring an illumination-numerical-aperture up to 1.

Abstract: The patent discloses a differential phase contrast (DPC) quantitative phase microscopy method based on the optimal illumination pattern design. Firstly, the optimal illumination pattern corresponding to the isotropic phase transfer function of DPC quantitative phase imaging is derived, which is determined as a semi-annular illumination pattern with the illumination numerical aperture NAill equal to the numerical aperture NAobj of the objective lens. The illumination intensity distribution varies with the cosine of the illumination angle, and it can be expressed as S(?)=cos(?). This patent effectively compensates for the frequency loss of phase transfer, not only the high-frequency responses of PTF are enhanced, but also the transfer responses of low-frequency phase information is significantly improved.

Abstract: An annular-irradiation high-resolution quantitative phase microimaging based on light intensity transfer equation is proposed here includes designing an annular aperture for the imaging system illumination; invoking the weak object approximation by using the parameters of annular illumination aperture and bright field microscopy to calculate a weak object optical transfer function (WOTF) on the basis of a partially coherent imaging theory; and collecting three intensity images by a camera and obtaining the quantitative phase image of object by resolving the light intensity transfer equation with a deconvolution algorithm.

Abstract: A super-rapid three-dimensional measurement method and system based on an improved Fourier transform contour technique is disclosed.

Abstract: A high-illumination numerical aperture-based large field-of-view high-resolution microimaging device, and a method for iterative reconstruction, the device comprising an LED array (1), a stage (2), a condenser (3), a microscopic objective (5), a tube lens (6), and a camera (7), the LED array (1) being arranged on the forward focal plane of the condenser (3). Light emitted by the i-th lit LED unit (8) of the LED array (1) passes through the condenser (3) and converges to become parallel light illuminating a specimen (4) to be examined, which is placed on the stage (2); part of the diffracted light passing through the specimen (4) is collected by the microscopic objective (5), converged by the tube lens (6), and reaches the imaging plane of the camera (7), forming an intensity image recorded by the camera (1). The present device and method ensure controllable programming of the illumination direction, while also ensuring an illumination-numerical-aperture up to 1.

Abstract: A super-rapid three-dimensional measurement method and system based on an improved Fourier transform contour technique is disclosed.

Abstract: Annular-irradiation high-resolution quantitative phase microimaging based on light intensity transfer equation is proposed here. First, an annular aperture is designed for the imaging system illumination. And then, by invoking the weak object approximation, the parameters of annular illumination aperture and bright field microscopy are used to calculate a weak object optical transfer function (WOTF) on the basis of a partially coherent imaging theory. Finally, three intensity images are collected by a camera and the quantitative phase image of object is obtained by resolving the light intensity transfer equation with a deconvolution algorithm. The present method effectively resolves the tradeoff between the cloudy low-frequency noise and high-frequency fuzziness in the light intensity transfer equation, and the spatial imaging resolution of phase reconstruction is greatly increased.