Kowa Company Limited

Ryusyo Industrial Co., Ltd.

Shigeru Takimoto

Satoshi Shimada

Tadashi Ichihashi

Toshiaki Nakagawa

Kazunori Matsumura

Atsushi Kakuuchi

Masayoshi Oouchi

Naoki Maeda

In a perimeter having means for measuring a visual field of an eye to be examined, means for monitoring fixation state and means for lighting the eye to be examined with a brightness necessary for monitoring the fixation state of the eye to be examined and means for correcting visibility, means for correcting visibility is provided so as to be freely moved between a set position corresponding to a measurement position of the eye to be examined and a stored position retracted to an outer periphery of a projection member. Such a perimeter further has means for detecting whether means for correcting visibility is at the set position or the stored position and an illustration controller for changing brightness of the illumination onto the eye to be examined through the means for lighting according to the detected position of means for correcting visibility.

Perimeter

An ocular fundus image is captured by a fundus camera. Blood vessel regions are erased from the ocular fundus image, and a luminance region greater than a prescribed luminance threshold value and having an area equivalent to a predetermined standard disc area is extracted as a region having a standard disc area. The region having the standard disc area is divided into a plurality of regions by a plurality of dividing lines extending radially from the center of gravity thereof, and divided regions are scanned radially from the center of gravity while angles are shifted to detect in each individual region a point at which luminance variation reaches a maximum. The contour line of the disc region is derived from these points.

Image processing method and image processing device

An ophthalmic photographic apparatus comprises a photographic mask for defining a fundus photography range, a photographic stop for eliminating light reflected from an anterior portion of the eye, and a focusing lens for bringing the fundus into focus. The photographic mask and the photographic stop are interlocked and move as one unit relative to the movement of the focusing lens in such a way that with respect to a photographic optical system, the photographic mask is maintained at a position substantially conjugate with an imaging plane of a CCD and the photographic stop is maintained at a position substantially conjugate with an anterior portion of the eye. The CCD is located at the image-side focal plane of the image-formation lens, the mask is located on the object-side focal plane of the focusing lens, and the photographic stop is located on the image-side focal plane of the focusing lens.

Ophthalmic photographic apparatus

An ophthalmic apparatus has an illumination optical system for illuminating a preselected point of a patient's eye with slit-light. Objective lenses are each disposed in an observation optical path for forming an image of the preselected point of the patient's eye. Eyepiece systems are disposed in respective ones of the observation optical paths for observing the image of the preselected point of the patient's eye. An imaging device captures the image of the preselected point of the patient's eye. An optical element guides the image of the preselected point of the patient's eye to the imaging device. The optical element is disposed between the objective lenses at a position that does not lie in any of the observation optical paths.

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Hamamatsu, Japan

Shigeru Takimoto