Nidek Co., Ltd.

Yasuhisa Murakami

Kazuhiro Yoshimura

Toshiaki Mizuno

Akihiro Hayashi

Noriji Kawai

Mikio Kurachi

Masakazu Endo

Noritsugu Nozawa

Yasumi Hikosaka

Yutaka Shirao

Kazuo Kawasaki

An eye distance measurement apparatus according to one aspect of the invention includes an interfering optical system that projects at least one piece of split light toward an examinee's eye, combines the split light, guides the combined light to a light receiving device and moves an optical member in order to adjust an optical path difference between the two pieces of split light, a mode switching unit that issues a mode switching signal for switching between a first measurement mode for moving the optical member at a first scanning rate and a second measurement mode for moving the optical member at a second scanning rate slower than the first scanning rate, and a calculation and control unit that measures an eye distance, based on an output signal of the light receiving device, obtained in the measurement mode corresponding to the mode switching signal.

Apparatus for measuring distance between eye tissues

A slit-lamp biomicroscope which illuminates an eye to be examined with slit illumination light, the biomicroscope comprises an illumination optical system provided with an illumination light source and a slit plate of which slit width is adjustable, a plurality of types of filters each having a different optical characteristic which are inserted into, and removed from an optical path of the illumination optical system, a filter detection device for detecting a type of the filter being inserted in the optical path of the illumination optical system, a light amount change device for changing an amount of illumination light on a side of the illumination light source with respect to the slit plate and a control device for controlling the light amount change device such that the amount of illumination light is adjusted to an amount corresponding to the detected filter based on a detection result obtained by the filter detection device.

Slit-lamp biomicroscope

An apparatus for visual acuity test of an examinee's eye comprises test chart presenting device for changing and presenting test chart to the examinee's eye, a switch for designating test chart to be presented by the test chart presenting means, a light delivery optical system for delivering luminous flux of test chart from the test chart presenting means to the examinee's eye, the light delivery optical system comprising a concave mirror for making the luminous flux of test chart optically from 4 m ahead of the examinee to infinit and a first reflection mirror for reflecting the luminous flux reflected the concave mirror to the examinee's eye, and reflecting angle adjusting device for adjusting reflection angle of the reflection mirror so as to fit to a height of the examinee's eye, a housing for internally mounting the test chart presenting means and the light delivery optical system, the housing having an aperture to allow the luminous flux of test chart pass therethrough and the aperture being provided with a filter on which reflection reducing coating is coated.

Apparatus for visual acuity test having an adjustable mirror

A lens meter including an illumination light source for illuminating a measurement target, a target projection optical system for projecting the measurement target onto an inspected lens, an observation optical system for observing a focused state of the projected target image and target moving device for moving the measurement target in an optical axis direction or the like to thereby measure a refracting power of the inspected lens on the basis of an amount in which the measurement target is moved in the optical axis direction. This lens meter includes a lens holder for holding the inspected lens substantially parallel to a plane on which the lens meter is installed, and a reflection system optical element for reflecting a measurement light passed through the inspected lens even times so that the measurement light is introduced into the observation optical system.

Lens meter for measuring a refractive power of a lens

The inventive method and apparatus are based on the display of a striped target with constantly accurate contrast to the patient for finding a visual function disturbance associated with such eye diseases as glaucoma or diabetic repinopathy at their earlier stage. A sight target of striped pattern is formed on the screen having a uniform brightness, the striped target is oscillated in the direction orthogonal to the striped pattern while varying the contrast of striped target and showing it to the patient, and the threshold of the pattern contrast which can be recognized visually by the patient is measured.

Growing community of inventors

Anjo, Japan

Yasuhisa Murakami