Sumitomo Metal Mining Company, Ltd.

Akira Terashima

Junji Iida

Kazuo Maeda

Masahiro Ito

Shintaro Ishikawa

Toshiki Kishimoto

Takeo Ide

Shuji Suzuki

Hiroshi Mori

Yoshiyuki Abe

Takumi Fujiwara

Hiroshi Mork

Takeshi Yokoyama

Shinji Yamauchi

A waveguide type optical control element which has an optical waveguide made of an insulating material having an electro-optic effect or a thermo-optic effect, and a control electrode provided in contact with or proximity to the optical waveguide; the optical waveguide having a propagation loss which is 1 dB/cm or less at wavelengths of from 1.3 &#x3bc;m to 1.6 &#x3bc;m. The control electrode is constituted of a conductive oxide film having a carrier electron concentration of 5.5&#xd7;10/cmor less and a resistivity of 9.5&#xd7;10&#x3a9;cm or less, and the conductive oxide film has a coefficient of extinction of light waves, of 0.240 or less at a wavelength of 1.55 &#x3bc;m.

Waveguide type optical control element and process for its fabrication

A non-destructive sugar content measuring apparatus having a plurality of trays on which vegetables and fruits are to be placed, a transport device for successively delivering the trays at appropriate intervals, and first, second and third measuring sections provided in the course of a transport path and at which laser beams having wavelengths &lgr;1, &lgr;2 and &lgr;3 are respectively made incident on each vegetable or fruit and the amount of light of each laser beam emergent from the vegetable or fruit is measured with a detector provided at each measuring section and the absorbance of each laser beam is determined from the amount of incident light made incident on the vegetable or fruit and the amount of detected light which has been measured with the detector, to measure the sugar content of the vegetables and fruits on the basis of each absorbance.

Non-destructive sugar content measuring apparatus

In a calibrator used for a non-destructive transmission optical measuring apparatus for quantitatively determining a specific component contained in a measuring object by making light incident on the measuring object at its light-incident area, detecting the light having entered, and having been transmitted through, the interior of the measuring object, at its light-emergent area set at a position different from the light-incident area, and measuring absorption of the light to quantitatively determine the specific component contained in the measuring object, the calibrator comprises a closed body having a light inlet and a light outlet, the interior of which is provided with a substrate having light absorption characteristics identical or similar to those of the specific component, and in which a light path length from the light inlet to the light outlet is so set as to be equal or substantially equal to an effective light path length of the light transmitted through the interior of the measuring object. This calibrator can make calibration on the non-destructive transmission optical measuring apparatus without destroying measuring objects and in a high precision and a good reproducibility and also in a simple way and short time.

Calibrator for non-destructive transmission optical measuring apparatus

A non-destructive taste characteristics measuring apparatus comprising trays and a measuring section provided in the course of a transport path and at which light is made incident on a vegetable or fruit to measure its taste characteristics, wherein the trays are each provided with at least two tray-side light passages one opening ends of which are so made as to come in contact with the vegetable or fruit and the other ends of which stand open outward at the bottom of the tray, and the measuring section has at least two measurement-side light passages one opening ends of which are positionally adjustable to the opening ends of the tray-side light passages at its part facing the bottom of said tray, and is provided with i) a means for making light incident on the vegetable or fruit through one of the measurement-side light passages and one of the tray-side light passages and ii) a detector which the light emergent from the vegetable or fruit enters through the other tray-side light passage and the other measurement-side light passage. The apparatus enables continuous measurement of taste characteristics such as sugar content and ripeness of vegetables and fruits at a high speed and a high precision without complicating the structure.

Non-destructive taste characteristics measuring apparatus and tray used

A non-destructive sugar content measuring apparatus for determining the sugar content of a vegetable or fruit by measuring absorption of light in sugar when near infrared light is made incident on the vegetable or fruit; comprising at least one light source that emits light rays having three kinds of wavelengths within a wavelength range of from 860 nm to 960 nm, and a detector that detects the absorption of light. The detector is disposed at a position except the position on an extended line of a straight line that connects i) the center of a light-incident area formed on the surface of the vegetable or fruit by the light emitted from the light source and incident on the vegetable or fruit and ii) the center of the vegetable or fruit, and at the same time at a position where the light-incident area formed on the surface of the vegetable or fruit by the incident light and the detection area formed on the surface of the vegetable or fruit by the light emergent from the vegetable or fruit and to be received by the detector do not overlap each other. This apparatus effectively enables non-destructive measurement of sugar content of vegetables and fruits in an accuracy of about plus-minus 1.0.degree.Brix, which is a resolving limit of sugar content that can be perceived by humans.

An optical waveguide produced from a lithium niobate single crystal substrate diffused thereon titanium is claimed, wherein, as the substrate is used a single crystal of lithium niobate having an optical absorbance coefficient of 0.03 cm.sup.-1 or less for a light 420 nm in wavelength. The optical waveguide according to the present invention shows improved resistance against optical damage as compared with prior art waveguides, and is therefore suitable for devices subjected to incidence beam of higher intensity.

Growing community of inventors

Chiba, Japan

Akira Terashima