Abstract: An image acquisition apparatus includes a light source configured to emit light, a dividing unit configured to divide the light from the light source into reference light and measurement light, an image forming unit configured to form a tomographic image of a subject based on interfered light in which return light from the subject irradiated with the measurement light and the reference light are interfered, a focus adjusting unit configured to adjust a focus of the measurement light, an optical-path-length adjusting unit configured to adjust an optical path length of the reference light, and a control unit configured to adjust the optical path length of the reference light by controlling the optical-path-length adjusting unit according a change in an optical path length of the measurement light caused by adjustment of the focus using the focus adjusting unit.

Abstract: Provided is an imaging apparatus including: a first scanning unit; a second scanning unit; an optical system joining an optical path extending to the second scanning unit to an optical path extending from the second scanning unit without the second scanning unit; a common optical system illuminating the fundus via the first scanning unit and the optical system with first measuring light based on a first light source, and illuminating the fundus via the first and second scanning units with second measuring light from a second light source; a first generating unit generating a tomographic image of the fundus based on interference light of the first measuring light, and reference light based on the first light source; and a second generating unit generating a fundus image based on the second measuring light, wherein the first generating unit generates the tomographic image at a predetermined position in the fundus image.

Abstract: An image acquisition apparatus includes a light source configured to emit light, a dividing unit configured to divide the light from the light source into reference light and measurement light, an image forming unit configured to form a tomographic image of a subject based on interfered light in which return light from the subject irradiated with the measurement light and the reference light are interfered, a focus adjusting unit configured to adjust a focus of the measurement light, an optical-path-length adjusting unit configured to adjust an optical path length of the reference light, and a control unit configured to adjust the optical path length of the reference light by controlling the optical-path-length adjusting unit according a change in an optical path length of the measurement light caused by adjustment of the focus using the focus adjusting unit.

Abstract: Provided is an optical coherence tomographic apparatus, including: a light source configured to generate light; a light splitting unit configured to split the light from the light source into reference light and measuring light; a detection unit configured to detect intensity of combined light obtained by combining the reference light with return light from an object to be inspected, which is irradiated with the measuring light; an image forming unit configured to form a tomographic image of the object to be inspected based on the detected intensity; and a locating unit configured to locate one of a plurality of objective lenses having different focal lengths and having the same dispersion amount on an optical axis at a position on an optical path of the measuring light opposed to the object to be inspected.

Abstract: Provided is an optical coherence tomographic apparatus, including: a light source configured to generate light; a light splitting unit configured to split the light from the light source into reference light and measuring light; a detection unit configured to detect intensity of combined light obtained by combining the reference light with return light from an object to be inspected, which is irradiated with the measuring light; an image forming unit configured to form a tomographic image of the object to be inspected based on the detected intensity; and a locating unit configured to locate one of a plurality of objective lenses having different focal lengths and having the same dispersion amount on an optical axis at a position on an optical path of the measuring light opposed to the object to be inspected.

Abstract: An ophthalmologic apparatus includes a reflective member that reflects light from a first scanning unit that scans an object to be examined with first light and light from a second scanning unit that scans the object with second light having a wavelength different from a wavelength of the first light so as to be applied to the object. The ophthalmologic apparatus includes an optical path synthesis and separation unit that is arranged on two optical paths from the scanning units to the reflective member, and synthesizes two optical paths from the scanning units to the object and separates an optical path of return light from the object into two optical paths on which the scanning units are arranged. A reflection optical path of the optical path synthesis and separation unit is arranged opposite to the object with respect to the optical path synthesis and separation unit.

Abstract: An ophthalmologic apparatus includes a reflective member that reflects light from a first scanning unit that scans an object to be examined with first light and light from a second scanning unit that scans the object with second light having a wavelength different from a wavelength of the first light so as to be applied to the object. The ophthalmologic apparatus includes an optical path synthesis and separation unit that is arranged on two optical paths from the scanning units to the reflective member, and synthesizes two optical paths from the scanning units to the object and separates an optical path of return light from the object into two optical paths on which the scanning units are arranged. A reflection optical path of the optical path synthesis and separation unit is arranged opposite to the object with respect to the optical path synthesis and separation unit.

Abstract: A catadioptric optical system of the present invention includes a catadioptric unit configured to condense light fluxes from an object and to form an intermediate image of the object, a field lens disposed at a position where the intermediate image are formed, and a dioptric unit configured to form the intermediate image on an image surface, and when ?cat denotes a smallest Abbe number in Abbe numbers of materials of the first and second optical elements configuring the catadioptric unit and ?dio denotes a smallest Abbe number in Abbe numbers of materials of a plurality of dioptric optical elements configuring the dioptric unit, ?dio<?cat is satisfied.

Abstract: The catadioptric system includes a first imaging optical system collecting light from an object and a second imaging optical system causing the light from the first imaging optical system to form an intermediate image and to cause the light from the intermediate image to form an optical image. The first imaging optical system includes a first optical element including a first light transmissive portion and a first back reflective portion, and a second optical element including a second light transmissive portion and a second back reflective portion. The first light transmissive portion, the second back reflective portion, the first back reflective portion and the second light transmissive portion introduce the light from the object to the second imaging optical system. The second imaging optical system includes an aspheric lens having a negative refractive power on and around the optical axis and a positive refractive index in its peripheral portion.

Abstract: The image acquisition apparatus includes an imaging optical system configured to form an image of an object, multiple image sensors each configured to capture an image of the object through the imaging optical system, multiple variable angle prisms disposed between the imaging optical system and the image sensors, and the variable angle prisms each being paired with one of the image sensors. A controller is configured to control each variable angle prism to correct defocus of the imaging optical system on the image sensor paired with that variable angle prism.

Abstract: The catadioptric system includes a first optical imaging system (catadioptric part) causing a light flux from an object to form an intermediate image and a second optical imaging system (dioptric part) causing the light flux from the intermediate image to form an image. In the first optical imaging system, the light flux sequentially passes a first transmissive portion, a second reflective portion, a first reflective portion and a second transmissive portion. In the second optical imaging system, consecutive four lens surfaces among plural lens surfaces placed between an aperture stop and an image surface have a negative combined refractive power, and a condition of ?0.52<?4n—max·Ymax<?0.14 is satisfied, ?4n—max represents a maximum value of the negative combined refractive power, and Ymax represents a maximum object height in a field-of-view of the catadioptric system at the object.

Abstract: A reflective optical system includes: a telescope section which includes a concave primary mirror and a concave secondary mirror; and a collimator section which includes at least one concave mirror disposed in a tilted manner with respect to an optical axis of the telescope section and at least one convex mirror disposed in a tilted manner with respect to the optical axis of the telescope section and on which converged light flux is incident, the collimator section receiving light flux from the telescope section.

Abstract: A microscope includes an objective optical system including an imaging optical system configured to form an image of an object, a re-imaging optical system configured to re-form an image of the object image formed by the imaging optical system, and a reflection unit arranged on an optical path between the imaging optical system and the re-imaging optical system and configured to be locally changeable in at least one of a position thereof in an optical axis direction and an inclination thereof relative to an optical axis, and an image sensor configured to capture the image re-formed by the objective optical system.

Abstract: An image acquisition apparatus includes: an imaging optical system configured to capture an image of an object; a plurality of re-imaging optical systems configured to re-image the object imaged by the imaging optical system; a reflecting optical system arranged on an optical path between the imaging optical system and the plurality of re-imaging optical systems; and a plurality of image-pickup elements configured to capture an image of the object re-imaged by the plurality of re-imaging optical systems. At least one of the plurality of image pickup elements is arranged in a plane different from a plane in which other image pickup elements are arranged; and the plurality of image-pickup elements are respectively capable of changing at least one of the positions in the direction of an optical axes of the corresponding re-imaging optical systems and the inclinations with respect to the optical axes on the basis of shape information of the object.

Abstract: An image acquisition apparatus includes an imaging optical system configured to image an object, a reimaging optical system configured to reimage the object imaged by the imaging optical system, a reflecting member disposed in an optical path between the imaging optical system and the reimaging optical system, an image sensor configured to capture an image of the object reimaged by the reimaging optical system, and to output the image, a first driving unit configured to change a tilt of the reflecting member relative to an optical axis of the imaging optical system, and a correction unit configured to correct a positional deviation of the image in a rotational direction, wherein the positional deviation of the image is generated according to a change in the tilt of the reflecting member.

Abstract: A catadioptric unit includes, in order from an object side to an image side, a first optical element including a first transmissive unit having positive refractive power disposed in the vicinity of an optical axis and, on the object side thereof, a first reflective unit disposed at an outer circumference relative to the first transmissive unit and having a reflective surface; and a second optical element including a second transmissive unit having negative refractive power in the vicinity of the optical axis and, on the image side thereof, a second reflective unit disposed at an outer circumference relative to the second transmissive unit and having a reflective surface. Radii of curvature of object-side and image-side surfaces of the second optical element, a thickness along the optical axis and a refractive index of a material of the second optical element are set to satisfy predetermined conditions.

Abstract: The catadioptric system includes a first imaging optical system collecting light from an object and a second imaging optical system causing the light from the first imaging optical system to form an intermediate image and to cause the light from the intermediate image to form an optical image. The first imaging optical system includes a first optical element including a first light transmissive portion and a first back reflective portion, and a second optical element including a second light transmissive portion and a second back reflective portion. The first light transmissive portion, the second back reflective portion, the first back reflective portion and the second light transmissive portion introduce the light from the object to the second imaging optical system. The second imaging optical system includes an aspheric lens having a negative refractive power on and around the optical axis and a positive refractive index in its peripheral portion.

Abstract: The catadioptric system includes a first optical imaging system (catadioptric part) causing a light flux from an object to form an intermediate image and a second optical imaging system (dioptric part) causing the light flux from the intermediate image to form an image. In the first optical imaging system, the light flux sequentially passes a first transmissive portion, a second reflective portion, a first reflective portion and a second transmissive portion. In the second optical imaging system, consecutive four lens surfaces among plural lens surfaces placed between an aperture stop and an image surface have a negative combined refractive power, and a condition of ?0.52<?4n—max·Ymax<?0.14 is satisfied, ?4n—max represents a maximum value of the negative combined refractive power, and Ymax represents a maximum object height in a field-of-view of the catadioptric system at the object.

Abstract: A catadioptric optical system of the present invention includes a catadioptric unit configured to condense light fluxes from an object and to form an intermediate image of the object, a field lens disposed at a position where the intermediate image are formed, and a dioptric unit configured to form the intermediate image on an image surface, and when ?cat denotes a smallest Abbe number in Abbe numbers of materials of the first and second optical elements configuring the catadioptric unit and ?dio denotes a smallest Abbe number in Abbe numbers of materials of a plurality of dioptric optical elements configuring the dioptric unit, ?dio<?cat is satisfied.

Abstract: A catadioptric optical system comprising a first imaging optical system including a concave mirror and forming an intermediate image of a first object, said first imaging optical system forming a reciprocating optical system that an incidence light and reflected light pass, a second imaging optical system for forming an image of the intermediate image onto a second object, and a first optical path deflective member, provided between the concave mirror and the intermediate image, for introducing a light from the first imaging optical system to the second imaging optical system, wherein said first optical path deflective member deflects a light in such a direction that a forward path of the first imaging optical system intersects a return path of the first imaging optical system, and wherein said intermediate image is formed without an optical element after a deflection.