Abstract: A slit illuminating apparatus in which slit illuminating light beams can be simply applied to an eye to be examined from different directions of application at a time or with lapse of time.

Abstract: A color-corrected vision testing apparatus and method are provided, such having a blue filtered incandescent illuminating source in a light-occluding housing for high contrast translumination of test patterns also in said housing to obtain improved testing of acuity levels.

Abstract: A retinal camera of the present invention has an illumination optical system for projecting an illumination light to a retina of an eye to be tested and a photographing optical system for photographing a retinal image of the eye to be tested. The illumination optical system is provided in a position substantially conjugate to the retina with a filter member. The filter member is formed as such that transmittance is relatively increased as it goes toward the peripheral portion from the central portion. When the retina of the eye to be tested is illuminated by this illumination optical system, an illumination light quantity per unit area at the peripheral portion side becomes larger than a illumination light quantity per unit area of the central portion side of an illumination light to be formed on the retina.

Abstract: An opthalmic apparatus in which the corneal reflection image of an illuminating light source for observing the front eye part of an eye to be examined is substantially prevented from mixing with the corneal reflection image of a light source for measurement, when the corneal reflection image is measured, to measure the shape of the cornea of the eye to be examined, whereby the accuracy with which the measurement of the shape of the cornea is measured is enhanced.

Abstract: An apparatus and method for measuring the anterior chamber diameter of the eye is disclosed in which a device illuminates the opposite end points of the annular groove. A gauging device cooperates with the illuminating device so as to provide to the viewer through a goneal assembly, a recognizable signal corresponding to a measure of the distance between the end points for gauging the distance.

Abstract: An eyeball microscope used for observing cornea endothelcells and the like, having an objective lens structure including an optical tip member which is formed of a material with lower refractive index than glass in order to avoid the undesired effect of reflection of illuminating light from the front surface of the optical tip member, and an adaptor for stably holding an impregnating liquid between the optical tip member and the cornea; the use of which will result in substantial reduction of reflection from the cornea surface and a corresponding increase in the field of view and resolution.