Abstract: An image pickup module comprises a lens assembly including a lens having a flange part, and a frame component for shading a circumferential surface excluding a neighborhood of a top portion of the flange part in the lens; an image pickup element which the top portion of the flange part touches; and an illumination element arranged around the lens assembly and the image pickup element. The image pickup module is constituted so that exit light from a luminescent surface of the illumination element does not reach directly to an exposed portion that is not shaded by the frame component of the flange part.

Abstract: A laser scanning microscope is disclosed that combines light from first and second scanning optical systems onto a common optical path using a beam combiner. A first plane-parallel transparent plate and a beam combiner are positioned on a support that may be moved relative to the common optical path. The first plane-parallel transparent plate has an optical thickness equal to the optical thickness of the beam combiner and is oriented with its surface normal lying substantially parallel with the surface normal of the beam combiner. An astigmatism-correcting optical element is provided on the common optical path, with the astigmatism-correcting optical element generating astigmatism that is equal in magnitude, but different in direction by 90 degrees, to the astigmatism generated by non-collimated light that is transmitted through the beam combiner. When the support is repositioned, spherical aberration in various light paths is maintained constant so that it may be easily corrected.

Abstract: An endoscope system is disclosed for detecting fluorescent light emitted in the near-infrared region by a plurality of fluorescent labeling materials introduced into a living tissue. An illumination system generates illumination light in the wavelength range 600 nm-2000 nm which serves as excitation light for the plurality of fluorescent labeling materials, and a detection system that can separately detect different ones of the plurality of fluorescent light emissions that are emitted at different wavelengths from among the plurality of fluorescent labeling materials is provided. The endoscope system may include a conventional-type endoscope having an insertion section, or a capsule endoscope that wirelessly transmits image data. By superimposing the image data obtained using reflected light in the visible region and fluorescent light emitted by the fluorescent labeling materials, improved diagnostic capabilities are provided.

Abstract: The invention provides a stereoscopic imaging optical system that has a total optical length short enough to be suitable for use in electron image microscopes. The stereoscopic imaging optical system comprises, in order from its object side, one objective lens DB and a plurality of zoom imaging optical systems ZI. Each zoom imaging optical system ZI comprises, in order from its object side, a positive first group G1, a negative second group G2, an aperture stop AS, a positive third group G3 and a positive fourth group G4. The second group moves for zooming on an optical axis, and the fourth group moves on the optical axis in association with the second group for correcting an image position fluctuation incidental to zooming. Various conditions are satisfied.

Abstract: The invention relates to an reimaging optical system that has a sufficiently enhanced magnification and better performance, and an endoscope using the same. The reimaging optical system 3 is adapted to re-form an image by an image guide 6 on a solid-state imaging device 4 having a diagonal length of 6.5 mm or longer, and satisfies the following condition. 0.6<(D×|?|)/V??(1). Here D is the diameter of the image guide 6, ? is the optical transverse magnification of the reimaging optical system 3, and V in mm is the minor axis direction length of an imaging area of the solid-state imaging device 4.

Abstract: A method for increasing the efficiency of additive drag reduction by establishing a drag-reducing viscoelastic coating on a surface. The method includes mixing a polymer into a concentrated solution that has approximately the same density as a fluid flowing over the surface, ejecting the mixture/solution into the flowing fluid in a manner such that a coating of polymer, which initially grows thicker with time, is adsorbed onto the surface, and reducing the ejection rate of the first fluid such that the coating of polymer then grows thinner with time. These steps may be repeated so that a desired minimum coating thickness is maintained over an extended period of time. The method reduces the polymer expenditure rate for a given drag reduction. Moreover, the produced viscoelastic coating impedes the attachment and growth of drag-producing natural organisms and may be applied without “down-time” (e.g., while underway).

Abstract: The invention relates to a high-performance imaging optical system that achieves a magnification high enough to be capable of microscopic viewing under an endoscope, and is compatible with high-definition imaging devices. The objective optical system comprises, at least in order from the object side, a positive, first group G1, a second group G2 and a third group G3. In association with an object point change, at least the second group G2 is moved along an optical axis. The objective optical system satisfies a condition with respect to an optical magnification ? upon focusing on the closest range.

Abstract: An image pickup apparatus includes an objective optical system, an image pickup element having a surface at an image formed by the objective optical system, and an etalon positioned between the objective optical system and the surface of the image pickup element. The etalon includes a gap, an optical path length of which is controllable for scanning the wavelengths transmitted by the etalon to thereby select the wavelengths that reach the surface. An optical filter is positioned between the objective optical system and the surface and has a first wavelength range over which incident light is reflected, a second wavelength range over which incident light is transmitted, and a boundary wavelength range that is bounded by the first and second wavelength ranges. The boundary wavelength range lies entirely within the wavelength range the peak transmission of the etalon can be scanned. A method of calibrating the etalon is also disclosed.

Abstract: A capsule endoscope is disclosed that includes a capsule and a transparent cover having a central axis and that is located in front of an objective optical system within the capsule. The objective optical system has a depth of field, a field of view, and an image surface that has curvature of field, and is arranged on the central axis of the transparent cover and the capsule. The field of view of the objective optical system includes a spherical surface that is tangent to the transparent cover at a periphery of the field of view, and the near point of the depth of field on the optical axis of the objective optical system is positioned farther from the objective optical system than is the transparent cover. Various conditions are satisfied so as to provide high quality imaging.

Abstract: An endoscope includes an illuminator that includes a light emitting surface for illuminating the inside of a living body, an objective optical system for forming an image of a specified object on one side of the objective optical system and illuminated by the illuminator, and a transparent cover that encompasses the illuminator and the one side of the objective optical system. The transparent cover includes an outer surface, and light emitted from the light emitting surface that is reflected by the outer surface satisfies a certain condition that helps prevent rearward dispersed light caused by scratches on, or substances adhering to, the external surface of the transparent cover from entering the entrance pupil of the objective optical system. The endoscope may also include a member for partially shielding the light emitted from the light emitting surface so as to limit the direction in which light is directed from said light emitting surface to the transparent cover.

Abstract: An endoscope image pickup unit is disclosed that captures magnified images of an object. An objective optical system of the image pickup unit includes, in order from the object side, a front lens group having positive refractive power and an aperture stop. Various conditions are satisfied so as to provide an observation scale factor in the range of about 200 to 2000 so that cellular details can be observed, as in a microscope, while keeping the objective optical system sufficiently compact for insertion within a patient. Also disclosed is a focus adjustment apparatus and method for the endoscope image pickup unit, and a focus range check apparatus and method for the endoscope image pickup unit.

Abstract: An imaging optical system includes a spherical or nearly spherical viewing port, an objective lens that includes an aspheric surface and is formed as a single lens element, and a solid-state image sensor that receives an image formed by the imaging optical system. Specified conditions are satisfied by the imaging optical system and the objective lens so that an in-focus image having low distortion, sufficient contrast, and formed by light rays of restricted angles of incidence is formed even for an object in contact with the viewing port. The specified conditions relate to features of the imaging optical system such as focal length and f-number of the imaging optical system, astigmatism and distortion of the imaging optical system, and pixel pitch of the solid-state image sensor. An endoscope that includes the imaging optical system is also disclosed.

Abstract: An immersion microscope objective formed of thirteen or fewer lens elements includes, in order from the object side, first and second lens groups of positive refractive power, a third lens group, a fourth lens group having negative refractive power with its image-side surface being concave, and a fifth lens group having positive refractive power with its object-side surface being concave. The first lens group includes, in order from the object side, a lens component that consists of a lens element of positive refractive power (when computed as being in air) and a meniscus lens element having its concave surface on the object side. Various conditions are satisfied to ensure that images of fluorescence, obtained when the immersion microscope objective is used in a laser scanning microscope that employs multiphoton excitation to observe a specimen, are bright and of high resolution. Various laser scanning microscopes are also disclosed.

Abstract: A capsule-type endoscope includes a capsule, an objective optical system, an image pickup element, and at least one illumination light source having a light-emitting surface, and a transparent cover. In several embodiments of the capsule-type endoscope according to the present invention, an inner surface of the transparent cover is spherical within a field of view of the objective optical system so as to have a center of curvature, the center of curvature is offset from the optical axis of the objective optical system, and a specified condition is satisfied so as to avoid flare in the objective optical system caused when light from the one (or more) illumination light source(s) enters the entrance pupil of the objective optical system. In another embodiment, the inner surface of the transparent cover has the shape of an ellipsoid. Observation methods using the capsule-type endoscope are also disclosed.

Abstract: An objective optical system includes, a first group having positive refractive power, a second group having positive refractive power, the first group having a first parallel flat plate, a diaphragm, a second parallel flat plate and a first plano-convex lens with its convex surface facing the image side in the above mentioned order as viewed from the object side, the first parallel flat plate, the second flat parallel plate and the first plano-convex lens forming a cemented lens, the second parallel flat plate being formed by an infrared absorption filter, the second group having a second plano-convex lens with its convex surface facing the object side.

Abstract: An improved laser scanning microscope and method of use are disclosed that enable polarization anisotropy measurements to be made with greater sensitivity and accuracy. A controllable optical element is provided in a light path between a laser source and a sample, and is controlled so that the sample is alternately irradiated with light beams that are orthogonally polarized. This enables the signal strength to be higher than with previous laser scanning microscopes. Moreover, because the orthogonally polarized light beams that are alternately incident onto a sample may be switched at a high rate, a reduction may be achieved in the influence of molecular motion within a sample in which high speed biological reactions are observed.

Abstract: An inexpensive fluorescent object is provided which may be used, for example, as a test object for color adjustment of a fluorescent endoscope system. The fluorescent object generates fluorescence while minimizing the generation of ‘noise’ at undesired wavelengths, and is made using a plastic that substantially does not deteriorate upon exposure to U.V. and visible radiation. A method of producing the fluorescent object is disclosed, namely, a plastic powder (such as PTFE) and an inorganic fluorescent powder (such as Mn-doped ZnS) are blended so as to form a mixture of these components, and the mixture is then molded by applying pressure to the mixture. An important feature of the invention is that heat is not added during any phase in the production of the fluorescent object, thereby preventing the inorganic fluorescent powder from being denatured when producing the fluorescent object.

Abstract: An objective optical system for endoscopes is characterized by comprising, in order from its object side, a stop, a first lens and a second lens. The first lens comprises a positive meniscus lens concave on its object side and the second lens comprises a positive lens convex on its object side. The following conditions (1), (2), (3) and (4) are satisfied: ?1.2<r1/f<?0.8??(1) ?1.0<r2/f<?0.6??(2) 2.1<f2/f<4.2??(3) nd1>1.65??(4) where r1 is the radius of curvature of the object-side surface of the first lens, r2 is the radius of curvature of the image-side surface of the first lens, f is the focal length of the whole optical system, f2 is the focal length of the second lens, and nd1 is the d-line refractive index of the first lens.

Abstract: An endoscope device includes a light source unit that creates multiple excitation lights having different peak wavelengths, an illumination unit, and an imaging unit that includes an objective optical system and an image pickup device. The imaging unit is capable of acquiring images of fluorescent lights having different peak wavelengths that are emitted by multiple fluorescent substances contained in a living organism. The illumination unit transmits the excitation lights to a tip of the endoscope device, and the multiple excitation lights are then directed so as to illuminate a living organism that contains multiple fluorescent substances. A variable transmittance optical element or an array of different type of filters may be placed before the image pickup device to separately detect the multiple fluorescent substances.

Abstract: A capsule endoscope is disclosed that includes means for illuminating an object, means for imaging the object, and a transparent cover having a center of curvature. The transparent cover covers the illumination means and the imaging means, and the imaging means includes an objective optical system and an image detecting element. The illumination means is positioned relative to the image detecting element, as viewed axially from the object side of the capsule endoscope, so that an area that is symmetrically positioned about the optical axis of the objective optical system from a light emitting area of the illumination means overlaps an area of the image detecting element, but does not overlap any areas of the image detecting element that are used for image detection.