Abstract: A method for performing differential interference contrast microscopy on a specimen includes collecting at least two images with illumination respectively having first and second beam-shear directions relative to a rotational orientation of the specimen, determining data associated with an intensity distribution of each of the collected images, and calculating values having a spatial distribution that is substantially independent of the rotational orientation of the specimen. A differential interference contrast microscope includes a beam-shearing assembly that includes a beam-shearing component. The beam-shearing assembly is configured to provide a variable shear vector without a movement of the beam-shearing component. A microscopy system can include the microscope and an imaging-control unit.

Abstract: In an apparatus and method for measuring parameters related to retardance and slow axis azimuth in sample specimens, a sample is illuminated by circularly polarized monochromatic light which is then analyzed by an elliptical analyzer at different settings. In another embodiment, light conditioned by an elliptical polarizer at various settings illuminates a specimen and the beam exiting the sample is analyzed by a circular analyzer. Background images obtained with selected settings of the elliptical analyzer/polarizer, but without the sample present. Algorithms are described which employ two specimen images with elliptical settings and three or two background images; or which employ three specimen images with elliptical settings; or which employ four specimen images with elliptical settings without an extinction setting; or which employ five specimen images with four elliptical settings and one extinction setting.

Abstract: A method for performing differential interference contrast microscopy on a specimen includes collecting at least two images with illumination respectively having first and second beam-shear directions relative to a rotational orientation of the specimen, determining data associated with an intensity distribution of each of the collected images, and calculating values having a spatial distribution that is substantially independent of the rotational orientation of the specimen. A differential interference contrast microscope includes a beam-shearing assembly that includes a beam-shearing component. The beam-shearing assembly is configured to provide a variable shear vector without a movement of the beam-shearing component. A microscopy system can include the microscope and an imaging-control unit.

Abstract: Apparatus and methods for measuring parameters related to retardance and slow axis azimuth in sample specimens. The invention can be used in imaging systems that obtain retardance and slow axis azimuth orientation at all points in a two-dimensional image simultaneously. A sample is illuminated by circularly polarized monochromatic light which is then analyzed by an elliptical analyzer at different settings. In another embodiment, light conditioned by an elliptical polarizer at various settings illuminates a specimen and the beam exiting the sample is analyzed by a circular analyzer. The elliptical analyzer/polarizer may have selectable ellipticity and azimuth angle, including in some cases a setting of circular polarization. Background images obtained with selected settings of the elliptical analyzer/polarizer, but without the sample present, are used in some embodiments to improve the measurement.

Abstract: In an apparatus and method for measuring retardance and slow axis azimuth in sample specimens, a sample is illuminated by circularly polarized monochromatic light which is then analyzed by an elliptical analyzer at different settings. In another embodiment, light conditioned by an elliptical polarizer at various settings illuminates a specimen and the beam exiting the sample is analyzed by a circular analyzer. The elliptical analyzer/polarizer may have selectable ellipticity and azimuth angle, including in some cases a setting of circular polarization. Background images obtained with selected settings of the elliptical analyzer/polarizer, but without the sample present, are used in some embodiments to improve the measurement.

Abstract: A method for performing differential interference contrast microscopy on a specimen includes collecting at least two images with illumination respectively having first and second beam-shear directions relative to a rotational orientation of the specimen, determining data associated with an intensity distribution of each of the collected images, and calculating values having a spatial distribution that is substantially independent of the rotational orientation of the specimen. A differential interference contrast microscope includes a beam-shearing assembly that includes a beam-shearing component. The beam-shearing assembly is configured to provide a variable shear vector without a movement of the beam-shearing component. A microscopy system can include the microscope and an imaging-control unit.

Abstract: In an apparatus and method for measuring retardance and slow axis azimuth in sample specimens, a sample is illuminated by circularly polarized monochromatic light which is then analyzed by an elliptical analyzer at different settings. In another embodiment, light conditioned by an elliptical polarizer at various settings illuminates a specimen and the beam exiting the sample is analyzed by a circular analyzer. The elliptical analyzer/polarizer may have selectable ellipticity and azimuth angle, including in some cases a setting of circular polarization. Background images obtained with selected settings of the elliptical analyzer/polarizer, but without the sample present, are used in some embodiments to improve the measurement.

Abstract: The invention provides a highly sensitive measurement of retardance and slow axis orientation, accurately and instantaneously, across a full two-dimensional image. There are no moving parts and there need not be any electro-optic tuning as part of the measurement. It is ideally adapted to real-time imaging and is well-suited to use with biological and medical samples, including visualizing structures in oocytes. The invention splits a light beam into several beams, which are analyzed using elliptical polarizers and the resultant intensity is measured. It can be constructed using a single pixilated detector, or several detectors, to achieve high spatial resolution when this is desired.

Abstract: Apparatus and methods for measuring retardance and slow axis azimuth in sample specimens. The invention can be used in imaging systems that obtain retardance and slow axis azimuth orientation at all points in a two-dimensional image simultaneously. A sample is illuminated by circularly polarized monochromatic light which is then analyzed by an elliptical analyzer at different settings. In another embodiment, light conditioned by an elliptical polarizer at various settings illuminates a specimen and the beam exiting the sample is analyzed by a circular analyzer. The elliptical analyzer/polarizer may have selectable ellipticity and azimuth angle, including in some cases a setting of circular polarization. Background images obtained with selected settings of the elliptical analyzer/polarizer, but without the sample present, are used in some embodiments to improve the measurement.

Abstract: A microscope system for determining optical properties of a specimen includes a source of polarized light, a detector for detecting the intensity of light incident thereon, an optical path extending from the source to the detector, a condenser for providing light from the source to the specimen, an objective for receiving light from the specimen, a support for mounting the specimen, a sectored variable retarder mounted in the optical path, and a polarized light analyzer mounted in the path between the sectored variable retarder and the detector. The variable retarder has a multiple sectors. Each sector is individually addressable by a control signal that affects the light retardation characteristics of the sector.

Abstract: A method for performing differential interference contrast microscopy on a specimen includes collecting at least two images with illumination respectively having first and second beam-shear directions relative to a rotational orientation of the specimen, determining data associated with an intensity distribution of each of the collected images, and calculating values having a spatial distribution that is substantially independent of the rotational orientation of the specimen. A differential interference contrast microscope includes a beam-shearing assembly that includes a beam-shearing component. The beam-shearing assembly is configured to provide a variable shear vector without a movement of the beam-shearing component. A microscopy system can include the microscope and an imaging-control unit.

Abstract: Apparatus and methods for measuring retardance and slow axis azimuth in sample specimens. The invention can be used in imaging systems that obtain retardance and slow axis azimuth orientation at all points in a two-dimensional image simultaneously. A sample is illuminated by circularly polarized monochromatic light which is then analyzed by an elliptical analyzer at different settings. In another embodiment, light conditioned by an elliptical polarizer at various settings illuminates a specimen and the beam exiting the sample is analyzed by a circular analyzer. The elliptical analyzer/polarizer may have selectable ellipticity and azimuth angle, including in some cases a setting of circular polarization. Background images obtained with selected settings of the elliptical analyzer/polarizer, but without the sample present, are used in some embodiments to improve the measurement.

Abstract: The invention provides a highly sensitive measurement of retardance and slow axis orientation, accurately and instantaneously, across a full two-dimensional image. There are no moving parts and there need not be any electro-optic tuning as part of the measurement. It is ideally adapted to real-time imaging and is well-suited to use with biological and medical samples, including visualizing structures in oocytes. The invention splits a light beam into several beams, which are analyzed using elliptical polarizers and the resultant intensity is measured. It can be constructed using a single pixilated detector, or several detectors, to achieve high spatial resolution when this is desired.

Abstract: A microscope system for determining optical properties of a specimen includes a source of polarized light, a detector for detecting the intensity of light incident thereon, an optical path extending from the source to the detector, a condenser for providing light from the source to the specimen, an objective for receiving light from the specimen, a support for mounting the specimen, a sectored variable retarder mounted in the optical path, and a polarized light analyzer mounted in the path between the sectored variable retarder and the detector. The variable retarder has a multiple sectors. Each sector is individually addressable by a control signal that affects the light retardation characteristics of the sector.