Abstract:
A tray or holder for tissue specimens, especially of excised tissue, such as biopsied specimens, is used with a confocal imaging system, especially a laser scanning confocal microscope system. The tray may be disposable after imaging of the specimen carried therein or may archive the specimen. A window supports the specimen. Clamps mounted inside the tray restrain the tissue. A compliant bag is mounted outside the tray on one side of a window of the tray on which the specimen is disposed. During imaging the specimen is immersed in a liquid contained in the tray having an index of refraction which closely matches the index of refraction of the tissue. The bag also contains an index matching liquid preferably having the same index as the liquid in the tray. A stabilizing plate is attached to a surface of the bag which faces the window. Selecting an immersion liquid, which equals the refractive index of the near surface tissues, minimizes wavefront distortion which may result from an effectively corrugated surface of the specimen.
Abstract:
A handheld imaging microscope for imaging tissue samples substantially beneath the surface of the tissue sample. The microscope includes an objective lens and a window defining a tissue contacting surface in pressure contacting relationship with the surface of the tissue sample when the tissue sample is imaged by the objective lens to view tissue structures for pathological applications. The objective lens focuses an illumination beam through the window to the tissue sample and receives returned reflected light of the beam representative of one or more sections of the tissue sample.
Abstract:
The quality of images produced by confocal microscopy, and especially scanning laser confocal microscopy, is enhanced especially for images obtained in turbid mediums such as many biological tissue specimens, by reducing speckle from scatterers that exist outside (above and below) the section which is being imaged by utilizing sheared beams, both of which are focused to laterally or vertically offset spots and polarizing the beams to have opposite senses of circular polarization (right and left handed circular polarization). The return light from the section of certain polarization is detected after passing through the confocal aperture of the confocal microscope. Images can be formed using optical coherence detection of the return light. Light from scatterers outside the section of interest, which are illuminated by both of the sheared beams, interfere thereby reducing speckle due to such scatterers, and particularly scatters which are adjacent to the section being imaged. Sheared beams having orthogonal linear polarization, as may be obtained from a Wollaston or Nomarski prism are converted into circularly polarized beams of opposite polarization sense by a quarter wave plate and focused into laterally displaced spot. A Dyson type lens is used to obtain sheared beams which when focused form vertically displaced spots. The optical signals representing reflections from the section are derived by polarizing optics which may either be a polarizing beamsplitter in the incident beam path or a retarder and analyzer. The retarder may be selected to provide different polarization phase shifts of the return light, and with the analyzer, detects the degree of elliptical polarization representing the optical activity and circular dichroism producing the optical signal representing the image.
Abstract:
The quality of images produced by confocal microscopy, and especially scanning laser confocal microscopy, is enhanced especially for images obtained in turbid mediums such as many biological tissue specimens, by reducing speckle from scatterers that exist outside (above and below) the focal plane region which is being imaged by utilizing sheared beams, both of which are focused to spots in the focal or image plane (region of interest) and polarizing the beams to have opposite senses of circular polarization (right and left handed circular polarization). The return light from the image plane of certain polarization is detected after passing through the confocal aperture of the confocal microscope. Light from scatterers outside the region of interest, which are illuminated by both of the sheared beams, interfere thereby reducing speckle due to such scatterers, and particularly scatters which are adjacent to the image plane. Sheared beams having orthogonal linear polarization, as may be obtained from a Wollaston or Nomarski prism are converted into circularly polarized beams of opposite polarization sense by a quarter wave plate. The optical signals representing reflections from the focal plane are derived by polarizing optics which may either, be a polarizing beamsplitter in the incident beam path or with a retarder and analyzer. The retarder may be selected to provide different polarization phase shift of the return light, and with the analyzer, detects the degree of elliptical polarization representing the optical activity and circular dichroism producing the optical signal representing the image.
Abstract:
A robust spectrophotometer (also known as a color spectrometer or colorimeter) is self contained in a housing which is adapted to be held-held and has all of the electrical, optical and electro optic elements mounted on a board captured within the housing at one end of which light from a sample is restricted to an object area and projected after being dispersed spectrally, as with a reflection grating, to an image area at a photodetector via a lens which has an optical axis and converges the dispersed light at the image area. The dispersive element is mounted on an arm having a pivot laterally offset from the dispersive element's surface where a diverging beam of light from the object area is incident and is deflected to the image area. The geometry is such that the dispersive element may be rotated to a position where the beam is specularly deflected (zeroth order diffraction), and the spectrometer calibrated when the dispersive element is in the specular reflection/deflection position. The path from the object area is approximately perpendicular to the optical axis, and then is folded by mirrors to direct the beam to incidence on the dispersive element, from which the beam is deflected and focused by the lens, the focal length of which is such that the image and object areas are in conjugate relationship. A pivotal foot on the housing having an aperture may be used to facilitate alignment of the sample with the entrance opening to the housing of the spectrophotometer.
Abstract:
A hand held microsurgical instrument for applying laser energy to selected locations (sites) in an area under the skin (or other exposed translucent tissue) to provide localized photothermolysis of underlying tissue at these sites, is described. The laser energy is focused into a spot within the tissue. This spot is of sufficiently small size so that the energy density is sufficient to provide surgical or treatment effects within the tissue without damaging the surface tissue. In dermatology, for example, the technique can be used to destroy endothelial cells in blood vessels which are desired to be removed, such spider veins (nevi) in the skin, hair follicles to prevent hair growth therefrom, or other microsurgical procedures. The area is visualized while the laser beam is steered, using a deflection system, in X and Y coordinates. A telecentric optical system, in which a mirror of the deflection system is located, directs the laser light essentially perpendicular to the area to be treated as the beam is scanned over the area. The optical system also focuses illumination light reflected from the area to a sensor matrix of a CCD video camera. The reflected illumination light is imaged essentially parallel to the optical axis in the object space thereby providing a precise, high resolution image corresponding to the area. The laser beam may be tracked as it is deflected over the area to the selected locations by visualization thereof on a display or monitor associated with the video camera. The locations are then apparent to the treating physician who can then effect an increase of the beam power or turn the beam on so as to treat the tissue in the selected locations.
Abstract:
A spectrophotometer which is highly manufacturable at minimum cost nevertheless provides precision of measurement of spectra components of light which is projected therein by maintaining precise optical alignment of optical and electrical components thereof. These components are mounted in a module which is contained in a housing having an entrance aperture which defines an object area for light the spectrum of which is measured by a photodetector in the module at an image area. The module has a base plate provided by a printed circuit board on which a closed wall encompasses an area (a corral) on one side of the circuit board. The wall is a one piece structure which extends to the vicinity of the edge of the board. It is assembled with the board as a unitary structure so that the assembly is made torsionally rigid and resists bending in the plane of the board. The module may be of sufficiently small size so as to be located in a housing which is hand held, thereby providing a hand-held spectrophotometer.
Abstract:
An optical data storage system comprises a multiple data surface medium and optical head. The medium comprises a plurality of substrates separated by a light transmissive medium. Data surfaces are located on the substrate surfaces which lie adjacent a light transmissive medium. The data surfaces are substantially light transmissive. The optical head includes an aberration compensator to allow the head to focus onto the different data surfaces and a filter to screen out unwanted reflected light.
Abstract:
A substrate has a pair of overlapping optical couplers for separately coupling a first and a second polarization component of a light beam into a first and a second waveguide channel. The channels are oriented with their longitudinal axis approximately perpendicular to each other. A first and a second optical detector are located in the first and second waveguide channels, respectively, for measuring the light intensity of the first and second polarization components.