Abstract: A method of performing phase retrieval and holographic image reconstruction of an imaged sample includes obtaining a single hologram intensity image of the sample using an imaging device. The single hologram intensity image is back-propagated to generate a real input image and an imaginary input image of the sample with image processing software, wherein the real input image and the imaginary input image contain twin-image and/or interference-related artifacts. A trained deep neural network is provided that is executed by the image processing software using one or more processors and configured to receive the real input image and the imaginary input image of the sample and generate an output real image and an output imaginary image in which the twin-image and/or interference-related artifacts are substantially suppressed or eliminated.

Abstract: A method of generating a color image of a sample includes obtaining a plurality of low resolution holographic images of the sample using a color image sensor, the sample illuminated simultaneously by light from three or more distinct colors, wherein the illuminated sample casts sample holograms on the image sensor and wherein the plurality of low resolution holographic images are obtained by relative x, y, and z directional shifts between sample holograms and the image sensor. Pixel super-resolved holograms of the sample are generated at each of the three or more distinct colors. De-multiplexed holograms are generated from the pixel super-resolved holograms. Phase information is retrieved from the de-multiplexed holograms using a phase retrieval algorithm to obtain complex holograms. The complex hologram for the three or more distinct colors is digitally combined and back-propagated to a sample plane to generate the color image.

Abstract: The concentration of mercury in a sample is measured by a reader secured to a camera-containing mobile electronic device. The reader has holders for sample and control solutions. First and second light sources emitting light at different colors illuminate the sample and control holders. Each holder contains gold nanoparticles, thymine-rich aptamers, and sodium chloride. The light sources illuminate the sample and control holders. An image is captured of the transmitted light through the sample and control holders, wherein the image comprises two control regions of interest and two sample regions of interest. The device calculates the intensity of the two control regions of interest and the two sample regions of interest and generates intensity ratios for the sample and control, respectively, at each color. The device calculates a normalized color ratio based on the intensity ratios and outputs a concentration of mercury based on the normalized color ratio.

Abstract: A method of imaging a sample having birefringent crystals (or other materials) using a lens-free polarized microscopy device includes illuminating the sample contained on a sample holder with circularly polarized partially coherent or coherent light and capturing lower resolution holographic images of the birefringent crystals with an image sensor. A polarization analyzer unit made from a ?/4 retarder and a linear polarizer is positioned between the sample holder and the image sensor. The lower resolution holographic images are obtained with the polarization analyzer unit in two different orientations (e.g. ˜90° orientations). Phase-retrieved, higher resolution images of the birefringent crystals at the different orientations are obtained using the lower resolution holographic images. A differential image is generated from the respective phase-retrieved, higher resolution images. An object support mask is applied to identify the birefringent crystals which can then be pseudo-colored.

Abstract: A fluorescent dye and quencher mixture for reporting on nucleic acid amplification from a sample includes a fluorescent intercalating dye, a dye sequestering or quenching agent such as hydroxynapthol blue (HNB) or caffeine, and primers, dNTPs, and a nucleic acid polymerizing enzyme or fragment thereof. The presence of the dye in combination with the dye sequestering or quenching agent improves the overall dynamic range of the fluorescent signal as well as shortens the time needed for visualization or image capture of amplified nucleic acid. The fluorescent dye and quencher mixture also enables the detection of nucleic acids in samples having low copy numbers.

Abstract: A device and method for imaging fluorescently labeled molecules (e.g., nucleic acids) includes securing a modular attachment device to the mobile phone with a sample containing stretched, fluorescently labeled nucleic acid molecules and illuminating the sample with excitation light to cause the fluorescently labeled nucleic acid molecules to emit fluorescent light. Images of the nucleic acids are captured using a camera of the mobile phone. The images from the mobile phone are transferred to a remote computer for image processing and analysis. The images are processed by the remote computer to generate analysis data of sample, wherein the analysis data includes the length of nucleic acid molecules contained in the sample or the length of molecular sub-region(s). The mobile phone or another computing device receives from the remote computer the analysis data and displays at least some of the analysis data thereon.

Abstract: A system for measuring chlorophyll concentration in a leaf sample includes a leaf-holding illuminator device with a main body containing a power source, a plurality of switchable light sources emitting light at different spectra (e.g., red and white light from a broadband light source), and a cap detachably secured to the main body using one or more fastening means. The leaf sample is interposed between the main body and the cap and held in place during imaging. The system includes a mobile electronic device having a camera configured to capture an image of the leaf illuminated by the plurality of switchable light sources, the mobile electronic device having wireless connectivity to a network and an application contained therein configured to transfer the images to a remote sever or computer via the network for data processing. A final chlorophyll index value is calculated based on the transferred images.

Abstract: An optical readout method for detecting a precipitate (e.g., a precipitate generated from the LAMP reaction) contained within a droplet includes generating a plurality of droplets, at least some which have a precipitate contained therein. The droplets are imaged using a brightfield imaging device. The image is subject to image processing using image processing software executed on a computing device. Image processing isolates individual droplets in the image and performs feature detection within the isolated droplets. Keypoints and information related thereto are extracted from the detected features within the isolated droplets. The keypoints are subject to a clustering operation to generate a plurality of visual “words.” The word frequency obtained for each droplet is input into a trained machine learning droplet classifier, wherein the trained machine learning droplet classifier classifies each droplet as positive for the precipitate or negative for the precipitate.

Abstract: A method of forming nanolenses for imaging includes providing an optically transparent substrate having a plurality of particles disposed on one side thereof. The optically transparent substrate is located within a chamber containing therein a reservoir holding a liquid solution. The liquid solution is heated to form a vapor within the chamber, wherein the vapor condenses on the substrate to form nanolenses around the plurality of particles. The particles are then imaged using an imaging device. The imaging device may be located in the same device that contains the reservoir or a separate imaging device.

Abstract: A micro-plate reader for use with a portable electronic device having a camera includes an opto-mechanical attachment configured to attach/detach to the portable electronic device and includes an array of illumination sources. A slot in the opto-mechanical attachment is dimensioned to receive an optically transparent plate containing an array of wells. Optical fibers are located in the opto-mechanical attachment and transmit light from each well to a reduced size header having, wherein the fiber array in the header has a cross-sectional area that is ?10× the cross-sectional area of the wells in the plate. A lens located in the opto-mechanical attachment transmits light from the header fibers to the camera. Software executed on the portable electronic device or other computer is used to process the images to generate qualitative clinical determinations and/or quantitative index values for the separate wells.

Abstract: A method for the label-free sizing of small, nanometer-sized objects such as particles includes a hand-held, portable holographic microscope that incorporates vapor condensation of nanolenses and time-resolved lens-free imaging. The portable device is used to generate reconstructed, time-resolved, and automatically-focused phase images of the sample field-of-view. The peak phase value for each object a function of working distance (z2) and condensation time (t) is used to measure object size. The sizing accuracy has been quantified in both monodisperse and heterogeneous particle solutions, achieving an accuracy of +/?11 nm for particles that range from 40 nm up to 500 nm. For larger particles, the technique still works while the accuracy roughly scales with particle size.

Abstract: A system for measuring chlorophyll concentration in a leaf sample includes a leaf-holding illuminator device with a main body containing a power source, a plurality of switchable light sources emitting light at different spectra (e.g., red and white light from a broadband light source), and a cap detachably secured to the main body using one or more fastening means. The leaf sample is interposed between the main body and the cap and held in place during imaging. The system includes a mobile electronic device having a camera configured to capture an image of the leaf illuminated by the plurality of switchable light sources, the mobile electronic device having wireless connectivity to a network and an application contained therein configured to transfer the images to a remote sever or computer via the network for data processing. A final chlorophyll index value is calculated based on the transferred images.

Abstract: A method of imaging includes illuminating a sample spaced apart from an image sensor at a multiple distances. Image frames of the sample obtained at each distance are registered to one another and lost phase information from the registered higher resolution image frames is iteratively recovered. Amplitude and/or phase images of the sample are reconstructed based at least in part on the recovered lost phase information.

Abstract: A method and system of imaging a moving object within a microfluidic environment includes illuminating a first side of a flow cell configured to carry the moving object within a flow of carrier fluid with an illumination source emitting at least partially coherent light, the at least partially coherent light passing through an aperture prior to illuminating the flow cell. A plurality of lower resolution frame images of the moving object are acquired with an image sensor disposed on an opposing side of the flow cell, wherein the image sensor is angled relative to a direction of flow of the moving object within the carrier fluid. A higher resolution image is reconstructed of the moving object based at least in part on the plurality of lower resolution frame images.

Abstract: A method for lens-free imaging of a sample or objects within the sample uses multi-height iterative phase retrieval and rotational field transformations to perform wide FOV imaging of pathology samples with clinically comparable image quality to a benchtop lens-based microscope. The solution of the transport-of-intensity (TIE) equation is used as an initial guess in the phase recovery process to speed the image recovery process. The holographically reconstructed image can be digitally focused at any depth within the object FOV (after image capture) without the need for any focus adjustment, and is also digitally corrected for artifacts arising from uncontrolled tilting and height variations between the sample and sensor planes. In an alternative embodiment, a synthetic aperture approach is used with multi-angle iterative phase retrieval to perform wide FOV imaging of pathology samples and increase the effective numerical aperture of the image.

Abstract: A method of imaging includes illuminating a sample spaced apart from an image sensor at a multiple distances. Image frames of the sample obtained at each distance are registered to one another and lost phase information from the registered higher resolution image frames is iteratively recovered. Amplitude and/or phase images of the sample are reconstructed based at least in part on the recovered lost phase information.

Abstract: A scanning system for fluorescent imaging includes a sample holder configured to hold a sample therein, the sample holder defining a sample holding region. A scanner head spans the sample holding region and is movable relative to the sample holder. An array of light sources is disposed on an opposing side of the sample holder and is angled relative thereto. Respective controller are operably coupled to the scanner head and the array of light sources, wherein one controller selectively actuates a one or more rows of the array of light sources and another controller controls movement of the scanner head to capture fluorescent light emitted from within the sample holder in response to illumination from the actuated light sources. A filter designed to filter out scattered light from the sample may be interposed between the sample holder and the scanner head.

Abstract: A method for obtaining a high resolution image of objects contained within a sample is disclosed that combines pixel super-resolution and phase retrieval techniques into a unified algorithmic framework that enables new holographic image reconstruction methods with significantly improved data efficiency, i.e., using much less number of raw measurements to obtain high-resolution and wide-field reconstructions of the sample. Using the unified algorithmic framework, twin image noise and spatial aliasing signals, along with other digital holographic artifacts, can be interpreted as noise terms modulated by digital phasors, which are all analytical functions of the imaging parameters including e.g., the lateral displacement between the hologram and the sensor array planes (x, y shifts), sample-to-image sensor distance (z), illumination wavelength (?), and the angle of incidence (?,?).

Abstract: A device and method for imaging fluorescently labeled molecules (e.g., nucleic acids) includes securing a modular attachment device to the mobile phone with a sample containing stretched, fluorescently labeled nucleic acid molecules and illuminating the sample with excitation light to cause the fluorescently labeled nucleic acid molecules to emit fluorescent light. Images of the nucleic acids are captured using a camera of the mobile phone. The images from the mobile phone are transferred to a remote computer for image processing and analysis. The images are processed by the remote computer to generate analysis data of sample, wherein the analysis data includes the length of nucleic acid molecules contained in the sample or the length of molecular sub-region(s). The mobile phone or another computing device receives from the remote computer the analysis data and displays at least some of the analysis data thereon.

Abstract: A system for three dimensional imaging of an object contained within a sample includes an image sensor, a sample holder configured to hold the sample, the sample holder disposed adjacent to the image sensor, and an illumination source comprising partially coherent light. The illumination source is configured to illuminate the sample through at least one of an aperture, fiber-optic cable, or optical waveguide interposed between the illumination source and the sample holder, wherein the illumination source is configured to illuminate the sample through a plurality of different angles.