Bio-rad Laboratories, Inc.

California Institute of Technology

Xin Heng

Changhuei Yang

Paul J Patt

Xiquan Cui

Axel Scherer

Demetri Psaltis

Daniel Y Chu

Guoan Zheng

Eli Hefner

Tom McCollum

Frank Shen

Don Flory

Mike Griffin

Lap Man Lee

Eugene Breniman

Tom Mccollum

Biological cells in a liquid suspension are counted in an automated cell counter that focuses an image of the suspension on a digital imaging sensor that contains at least 4,000,000 pixels each having an area of 2&#xd7;2 &#x3bc;m or less and that images a field of view of at least 3 mm. The sensor enables the counter to compress the optical components into an optical path of less than 20 cm in height when arranged vertically with no changes in direction of the optical path as a whole, and the entire instrument has a footprint of less than 300 cm. Activation of the light source, automated focusing of the sensor image, and digital cell counting are all initiated by the simple insertion of the sample holder into the instrument. The suspension is placed in a sample chamber in the form of a slide that is shaped to ensure proper orientation of the slide in the cell counter.

Compact automated cell counter

A system for performing high-speed, high-resolution imaging cytometry includes a scanning region that is illuminated by light including at least first and second wavelength bands. The system also includes a cell transport mechanism that transports a cell through the scanning region such that the cell is illuminated. The system further includes a set of at least one linear light sensor, and an optical system that selectively directs light emitted from the cell to two portions of the linear light sensor set such that emitted light in a third wavelength band is primarily directed to a first portion of the linear light sensor set, and emitted light in a fourth wavelength band is primarily directed to a second portion of the linear light sensor set. The system repeatedly takes readings of light falling on the linear light sensor set while the cell is transported through the scanning region.

Serial-line-scan-encoded multi-color fluorescence microscopy and imaging flow cytometry

A microassembled imaging cytometer includes a sensing location that undergoes relative motion with a cell. Light from a light source is focused by a focusing element to a plurality of focused illumination spots or lines at the sensing location, illuminating the cell as the cell traverses the sensing location. A collection lens collects light emanating from the cell and refocuses the collected light onto an array light sensor. The focusing element may include an array of microlenses having spherical or aspheric surfaces. The system may include a processing unit that constructs a digital image of the cell based at least in part on signals produced by the array light sensor indicating the intensity and distribution of light falling on the array light sensor. The system may characterize cells using light emanating from the cells by fluorescence.

Microassembled imaging flow cytometer

A surface wave assisted system having an aperture layer with a surface and an aperture, and a plurality of grooves around the aperture. The plurality of grooves is configured to generate an optical transfer function at the aperture by inducing a surface wave for interfering with transmission of light of a range of spatial frequency.

Surface wave assisted structures and systems

A flow cytometry system includes a flow element through which a cell is transported in a flowing fluid. The flow element includes a bore bounded by a wall. A light source is configured to illuminate the cell. An optical system receives light emanating from the cell and directs at least some of the received light to a light sensor. The optical system includes a numerical-aperture-increasing lens at a wall of the flow element. At least some of the received light passes through the numerical-aperture-increasing lens. The flow cytometry system may also include a beam splitter that directs two wavelength bands of the emanating light such that light in two wavelength band preferentially reach different sensing locations via different paths. The system may also include an optical element placed in one of the paths, shifting a focal location of the affected path to compensate for chromatic aberration of the numerical-aperture-increasing lens.

Cytometry system with solid numerical-aperture-increasing lens

Systems and methods for performing cytometry using a linear light sensor. An illumination field, a line scanned by the linear light sensor, or both are swept across a cell to be imaged. Relative motion between the cell and the swept illumination may be created using a movable optical component or components, by adhering cells to a plate and transporting the plate or by other techniques.

Line scan cytometry systems and methods

A system for performing high-speed, high-resolution imaging cytometry utilizes a line-scan sensor. A cell to be characterized is transported past a scan region. An optical system focuses an image of a portion of the scan region onto at least one linear light sensor, and repeated readings of light falling on the sensor are taken while a cell is transported though the scan region. The system may image cells directly, or may excite fluorescence in the cells and image the resulting light emitted from the cell by fluorescence. The system may provide a narrow band of illumination at the scan region. The system may include various filters and imaging optics that enable simultaneous multicolor fluorescence imaging cytometry. Multiple linear sensors may be provided, and images gathered by the individual sensors may be combined to construct an image having improved signal-to-noise characteristics.

Cell counts that distinguish between live and dead cells while providing an accurate count of the total of live and dead cells are obtained by the use of a vital stain in conjunction with illumination of the cell population and the taking of light images at different wavelengths, one which is not absorbed by the stain and one that is absorbed by the stain. Masking and inaccuracies in the counting of dead cells is thereby avoided.

Viability cell counting by differential light absorption

An optical system and associated method enable near real time optical phase conjugation. In the method, a translucent medium is illuminated by a sample illumination beam. Light scattered by the medium is directed to an electronic image sensor while a reference beam is also directed to the electronic image sensor. The scattered light and the reference beam form an interference pattern at the electronic image sensor. A digital representation of the interference pattern is recorded using the electronic image sensor, and the characteristics of a conjugate of the sample beam are computed from the numerical representation. A conjugate beam having the computed characteristics is generated using a configurable optical element and directed back to the translucent medium. The generation of the conjugate beam may be accomplished using a spatial light modulator.

Near real time optical phase conjugation

A differential interference contrast (DIC) determination device and method utilizes an illumination source, a layer having a pair of two apertures that receive illumination from the illumination source, and a photodetector to receive Young's interference from the illumination passing through the pair of two apertures. In addition, a surface wave assisted optofluidic microscope and method utilize an illumination source, a fluid channel having a layer with at least one aperture as a surface, and a photodetector that receives a signal based on the illumination passing through the aperture. The layer is corrugated (e.g., via fabrication) and parameters of the corrugation optimize the signal received on the photodetector.

On-chip phase microscope/beam profiler based on differential interference contrast and/or surface plasmon assisted interference

Embodiments of the present invention relate to techniques for improving optofluidic microscope (OFM) devices. One technique which may be used eliminates the aperture layer covering the light detector layer. Other techniques retain the aperture layer, reversing the relative position of the light source and light detector such that light passes through the aperture layer before passing through the fluid channel to the light detector. Another technique adds an optical tweezer for controlling the movement of objects moving through the fluid channel. Another technique adds an optical fiber bundle to relay light from light transmissive regions to a remote light detector. Another technique adds two electrodes at ends of the fluid channel to generate an electrical field capable of moving objects through the fluid channel while suppressing rotation. These techniques can be employed separately or in combination to improve the capabilities of OFM devices.

Optofluidic microscope device with photosensor array

Embodiments of the present invention relate to a surface wave enabled darkfield aperture structure comprising an aperture layer, a aperture in the aperture layer and a plurality of grooves around the aperture. The aperture layer has a first and second surface. The plurality of grooves is in the first surface. A surface wave propagates along at least the first surface. The plurality of grooves is configured to generate a darkfield at the aperture by modifying the surface wave to cancel out direct transmission of a uniform incident light field received by the aperture.

Surface wave enabled darkfield aperture

A differential interference contrast (DIC) determination device and method utilizes an illumination source, a layer having a pair of two apertures that receive illumination from the illumination source, and a photodetector to receive Young's interference from the illumination passing through the pair of two apertures. In addition, a surface plasmon assisted optofluidic microscope and method utilize an illumination source, a fluid channel having a layer with at least one aperture as a surface, and a photodetector that receives a signal based on the illumination passing through the aperture. The layer is corrugated (e.g., via fabrication) and parameters of the corrugation optimize the signal received on the photodetector.

Growing community of inventors

Emeryville, CA, United States of America

Xin Heng