A microscope unit comprises: a main lens barrel of an imaging optical system; and an illumination lens barrel of an illumination optical system connected to the main lens barrel, the illumination optical system having: a collector lens that collects light that has been irradiated from a light source; a fly-eye lens allowing to be transmitted therethrough light from the collector lens; a first relay lens having lenses that relay light from the fly-eye lens; a field stop that stops down a range of light from the first relay lens; a second relay lens that relays to a beam splitter light from the first relay lens; and the beam splitter guiding at least a part of light incident thereon to the objective lens and allowing to be transmitted therethrough to a side of an imaging sensor at least a part of light incident thereon from the objective lens.

A microscope unit comprises: a main lens barrel of an imaging optical system, the main lens barrel being configured capable of being fitted with an imaging sensor and an objective lens; and an illumination lens barrel of an illumination optical system, the illumination lens barrel being connected to the main lens barrel and configured capable of being fitted with a light source, the illumination lens barrel having: a first lens barrel configured capable of being fitted with the light source; and an intermediate lens barrel connecting the main lens barrel and the first lens barrel, and a field stop of light irradiated from the light source being disposed more inwardly than an outer peripheral surface of the intermediate lens barrel is.

An observation device includes: a macro observation system; and a micro observation system. The macro observation system and the micro observation system are arranged so as to satisfy a first condition. The first condition is that a distance from a macro optical axis to a micro optical axis is equal to or less than a square root of a sum of squares of a first distance and a second distance. The first distance is a distance between the macro optical axis and a central axis of an outer diameter of the nosepiece. The second distance is a distance in a first direction between the central axis of the outer diameter and a side surface of the nosepiece. The first direction is a direction orthogonal to the macro optical axis and orthogonal to a line segment connecting the macro optical axis and the central axis of the outer diameter.

Provided is a microscope apparatus including: a microscope section configured to perform magnified observation of a subject's eye while obtaining a red reflex caused by irradiating a fundus of the subject's eye with illuminating light; a holding section configured to hold the microscope section; and a tilting section configured to tilt an illumination optical axis which is an optical axis of an illumination optical system, and an observation optical axis which is an optical axis of an observation optical system in the microscope section, around a tilt reference point in an interior of the subject's eye as a base point, while maintaining a substantially coaxial state between the illumination optical axis and the observation optical axis.

Disclosed is a technology for illuminating a specimen in a desired uniform illumination pattern and capturing an image of a wide field of view in a low background illumination environment. Provided, for example, is a fluorescence microscope apparatus including a first illumination optics, a second illumination optics, and an imaging optics. The first illumination optics includes a first light source for exciting fluorescence in a specimen, a spatial light modulation element, and a first illumination optical member for uniformly illuminating the spatial light modulation element. The second illumination optics includes a second illumination optical member for forming an image of a light beam from the spatial light modulation element on a specimen surface. The imaging optics includes an imaging optical member and an imaging element. The imaging optical member captures an image of the specimen surface.

Disclosed is a technology for illuminating a specimen in a desired uniform illumination pattern and capturing an image of a wide field of view in a low background illumination environment. Provided, for example, is a fluorescence microscope apparatus including a first illumination optics, a second illumination optics, and an imaging optics. The first illumination optics includes a first light source for exciting fluorescence in a specimen, a spatial light modulation element, and a first illumination optical member for uniformly illuminating the spatial light modulation element. The second illumination optics includes a second illumination optical member for forming an image of a light beam from the spatial light modulation element on a specimen surface. The imaging optics includes an imaging optical member and an imaging element. The imaging optical member captures an image of the specimen surface.

A illumination arrangement for a microscope for illuminating a sample with a light sheet includes an illumination input configured to feed an illumination beam along an optical axis of the illumination arrangement and an illumination output which faces a sample side and is configured to output the illumination beam to the sample side. A focusing optical system is provided with a set depth of focus. At least one optical modification element is configured to geometrically modify the illumination beam. Different rays of the illumination beam intersect the optical axis within an axis intersection region at the illumination output. The axis intersection region extends over at least the depth of focus of the focusing optical system along the optical axis.

An optical illumination device (10) includes: a laser light source (1); microlens arrays (2, 3) through which light emitted from the laser light source (1) passes; a moving mechanism (5) that moves the microlens arrays (2, 3) without changing an optical length from the laser light source (1); and a Fourier lens (4) through which light passing through the microlens arrays (2, 3) passes.

An optical illumination device (10) includes: a laser light source (1); microlens arrays (2, 3) through which light emitted from the laser light source (1) passes; a moving mechanism (5) that moves the microlens arrays (2, 3) without changing an optical length from the laser light source (1); and a Fourier lens (4) through which light passing through the microlens arrays (2, 3) passes.

An optical apparatus having an illumination module with a carrier, which has at least one light-transmissive region, for example. The illumination module has a plurality of light sources, which are arranged on the carrier.