Kowa Company Limited

Waseda University

Itaru Yoshizawa

Akihiko Uchiyama

Akihiro Fujita

Sunao Takeda

Taisuke Hirono

Chikashi Koike

Kouji Kobayashi

Mamoru Ueda

Kenji Yanashima

Makoto Nakai

Kohji Ohbayashi

A tonometry device includes a contact device for contacting the object, means for vibrating the contact device and the object, means for applying a voltage to the vibration means, means for measuring a current flowing through the vibration means, and an information processing means. The information processing means determines two resonance points of the device and the measured object by measuring current through the system at a plurality of vibrational frequencies. The information processing means then determines the internal pressure of the object by determining that a first pressure is higher than a second pressure by determining that the first pressure has a lower measured current than the second pressure at frequencies outside of the range of frequencies between the resonance points, and that the first pressure has a higher measured current than the second pressure at frequencies within the range of frequencies between the resonance points.

Pressure measuring method, pressure measuring device, and tonometer

An optical measuring instrument which enables measurement of necessary data in a short period of time and uses a light with a short coherence length. In this instrument, such a light emitted from a light source is divided into a measurement light and a plurality of reference lights. The plurality of reference lights are processed by different frequency modulations, and then multiplexed with a light reflected from a measurement object irradiated by the measurement light. On the basis of an output of a photoelectric converter for detecting the level of the multiplexed light and the frequency of each reference light, optical characteristic data related to a plurality of measurement points are calculated.

Optical coherence tomography have plural reference beams of differing modulations

An ophthalmic light irradiation apparatus includes a deflection member and an operating section for driving the deflection member to deflect a laser beam to the interior of a patient's eye. The operating member includes an operating lever, a fixed ball member affixed to the operating lever, and a movable ball member integrally mounted on one end of the operating lever and movably engaged with the fixed ball member. The movable ball member is offset along the axial direction of the operating lever, which is supported so that it can be tilted in a desired direction within a plane substantially orthogonal to the axis of the lever. Movement of the movable ball member produced by tilting the operating lever is divided into first and second orthogonal directions for transmission to the deflection member. The apparatus is structurally simple in construction and has good operability enabling the laser beam to be precisely controlled.

Ophthalmic light irradiation apparatus

A fundus examining device is provided in which laser light from a laser light source is deflected for scanning in two dimensions over an eye fundus of an eye being examined and light reflected from the eye fundus is photoelectrically detected with a photodetector to obtain fundus information. The fundus examining device includes an optical system for observing an anterior portion of the eye which is illuminated by illuminating light to determine how the pupil of the eye is dilated. To this end, an objective mirror is provided which reflects light of the wavelength of the laser beam but is transparent to the illuminating light. The objective mirror reflects the deflected laser beam to illuminate the fundus of the eye, while guiding light from the illuminated anterior portion of the eye to the observing optical system.

Fundus examination device

Growing community of inventors

Tokyo, Japan

Itaru Yoshizawa