Abstract: A laser condensing optical system of the present invention includes a laser beam source which emits a laser beam, a condensing optical system which is arranged between the laser beam source and a medium and condenses the laser beam in the medium, and a laser divergence point moving unit which can move the position of a laser divergence point of the laser beam along an optical axis of the laser beam in accordance with the refractive index of the medium in which the laser beam is desired to be condensed and the distance from a surface of the medium to a position where the beam is desired to be condensed.

Abstract: A laser condensing optical system of the present invention includes a laser beam source which emits a laser beam, a condensing optical system arranged between the laser beam source and a medium, the condensing optical system condensing the laser beam in the medium and recondensing light from a condensing point, a photodetector which detects the light recondensed by the condensing optical system, and a laser divergence point moving unit which moves the position of a laser divergence point of the laser beam along an optical axis of the laser beam in accordance with the refractive index of the medium in which the laser beam is condensed and the distance from a surface of the medium to a condensing position.

Abstract: A laser condensing optical system of the present invention includes a laser beam source which emits a laser beam, a condensing optical system which is arranged between the laser beam source and a medium and condenses the laser beam in the medium, and a laser divergence point moving unit which can move the position of a laser divergence point of the laser beam along an optical axis of the laser beam in accordance with the refractive index of the medium in which the laser beam is desired to be condensed and the distance from a surface of the medium to a position where the beam is desired to be condensed.

Abstract: A laser condensing optical system of the present invention includes a laser beam source which emits a laser beam, a condensing optical system which is arranged between the laser beam source and a medium and condenses the laser beam in the medium, and a laser divergence point moving unit which can move the position of a laser divergence point of the laser beam along an optical axis of the laser beam in accordance with the refractive index of the medium in which the laser beam is desired to be condensed and the distance from a surface of the medium to a position where the beam is desired to be condensed.

Abstract: A laser condensing optical system of the present invention includes a laser beam source which emits a laser beam, a condensing optical system arranged between the laser beam source and a medium, the condensing optical system condensing the laser beam in the medium and recondensing light from a condensing point, a photodetector which detects the light recondensed by the condensing optical system, and a laser divergence point moving unit which moves the position of a laser divergence point of the laser beam along an optical axis of the laser beam in accordance with the refractive index of the medium in which the laser beam is condensed and the distance from a surface of the medium to a condensing position.

Abstract: A laser condensing optical system of the present invention includes a laser beam source which emits a laser beam, a condensing optical system which is arranged between the laser beam source and a medium and condenses the laser beam in the medium, and a laser divergence point moving unit which can move the position of a laser divergence point of the laser beam along an optical axis of the laser beam in accordance with the refractive index of the medium in which the laser beam is desired to be condensed and the distance from a surface of the medium to a position where the beam is desired to be condensed.

Abstract: Microscope apparatus and a method are disclosed for avoiding a reduction in intensity at the periphery of a microscope image that is detected by an electronic image-detector and then displayed. The method includes inserting one or more stops along the optical axis of the microscope, said stop(s) having a central transmissive region and a blocking region outside the central transmissive region; and positioning at least one stop so as to simultaneously block peripheral portions of axial and abaxial light fluxes from a sample under observation from being incident onto the electronic image detector, thereby making the axial and abaxial light fluxes that are incident onto the electronic image detector substantially equal in detected brightness.

Abstract: An optical microscope has a revolver for selectively inserting a plurality of objective lenses including a low-magnification (very-low-magnification) objective lens on an optical axis for observation light. In fluorescence observation using the low-magnification objective lens, the effective diameter of an observation optical system is set larger than that of an illumination optical system. With this arrangement, fluorescence observation using the low-magnification objective lens can be stably performed. A cube unit having a plurality of cubes corresponding to the respective microscopic methods is arranged in the optical microscope. An auxiliary lens serving as a very-low-magnification objective lens is mounted in this cube unit. The auxiliary lens can be automatically used in observation using the very-low-magnification objective lens. With this arrangement, a compact optical microscope excellent in operability can be realized.

Abstract: Microscope apparatus and a method are disclosed for avoiding a reduction in intensity at the periphery of a microscope image that is detected by an electronic image-detector and then displayed. The method includes inserting one or more stops along the optical axis of the microscope, said stop(s) having a central transmissive region and a blocking region outside the central transmissive region; and positioning at least one stop so as to simultaneously block peripheral portions of axial and abaxial light fluxes from a sample under observation from being incident onto the electronic image detector, thereby making the axial and abaxial light fluxes that are incident onto the electronic image detector substantially equal in detected brightness.

Abstract: An optical element switching device is provided wherein a plurality of optical elements are held by a guide mechanism for guiding them to move straight or rotate and arranged on a turret, and positioned by a positioning part comprising a spring for pushing a ball into V grooves formed at a rotarys shaft of the turret rotated by a first motor wherein, a selected one of the optical elements is stopped in an optical path (i.e. an optical axis of objectives), and wherein the optical element is moved by a second motor along a direction in which it is guided by the guide mechanism, so that corrections such as adjustment of the contrast and the like are automatically executed at switching operations.

Abstract: An optical microscope has a revolver for selectively inserting a plurality of objective lenses including a low-magnification (very-low-magnification) objective lens on an optical axis for observation light. In fluorescence observation using the low-magnification objective lens, the effective diameter of an observation optical system is set larger than that of an illumination optical system. With this arrangement, fluorescence observation using the low-magnification objective lens can be stably performed. A cube unit having a plurality of cubes corresponding to the respective microscopic methods is arranged in the optical microscope. An auxiliary lens serving as a very-low-magnification objective lens is mounted in this cube unit. The auxiliary lens can be automatically used in observation using the very-low-magnification objective lens. With this arrangement, a compact optical microscope excellent in operability can be realized.

Abstract: An optical microscope has a revolver for selectively inserting a plurality of objective lenses including a low-magnification (very-low-magnification) objective lens on an optical axis for observation light. In fluorescence observation using the low-magnification objective lens, the effective diameter of an observation optical system is set larger than that of an illumination optical system. With this arrangement, fluorescence observation using the low-magnification objective lens can be stably performed. A cube unit having a plurality of cubes corresponding to the respective microscopic methods is arranged in the optical microscope. An auxiliary lens serving as a very-low-magnification objective lens is mounted in this cube unit. The auxiliary lens can be automatically used in observation using the very-low-magnification objective lens. With this arrangement, a compact optical microscope excellent in operability can be realized.

Abstract: The invention provides a microscope objective having a working distance longer than achieved so far in the prior art even at more than 100 magnifications. The objective comprises a lens group A that comprises a positive meniscus lens concave toward an object side thereof and a plurality of cemented lenses, has positive refractive power and converts light rays from an object to a converging light beam, and a lens group B having negative refractive power, and satisfies condition (1):5<.vertline.f.sub.A /f.sub.B .vertline.<20 (1)where f.sub.A is a focal length of said lens group A and f.sub.B is a focal length of said lens group B.

Abstract: The invention provides an anticarcinogenic drug composition which effectively inhibits the recurrence of hepatocellular carcinoma (the occurrence of second primary tumor), the occurrence of hepatocellular carcinoma in high risk groups with chronic hepatitis and liver cirrhosis, the occurrence of cervical carcinoma intraepitheliale, lung adenocarcinoma, lung squamous cell carcinoma, mammary tumor, and the like and is highly safe. The anticarcinogenic drug composition contains 3,7,11,15-tetramethyl-2,4,6,10,14-hexadecapentaenoic acid or a salt thereof.