Kabushiki Kaisha Toshiba

Topcon Corporation

Hideo Nagai

Kenji Sano

Taeko I Urano

Tomokazu Domon

Hironori Fukuda

Masashi Sahashi

Shinya Sakurada

Toru Tojo

Takahiro Hirai

Hisakazu Yoshino

Kyoji Yamashita

Mitsuo Tabata

Akihiko Tsutai

Yasushi Sanada

Makoto Taya

Akemi Miwa

Noboru Kobayashi

Tsutomu Yamashita

An article including a substrate and an invisible symbol on the substrate is disclosed. The invisible symbol is formed by a compound which includes a cyano group and has an infrared absorption wavelength apart from that of the substrate when heated.

Method and apparatus for reading invisible symbol

An invisible symbol reading apparatus includes a heating unit for heating an invisible symbol formed on a sample and containing a material which emits infrared light when heated, a detecting unit for detecting infrared light emitted from the invisible symbol, and an arithmetic operation unit for binarizing a detection signal from the detecting unit. The arithmetic operation unit calculates a differential coefficient of the detection signal, that corresponds to a position on the sample. On the basis of upper and lower threshold values set for the differential coefficient, the arithmetic operation unit determines a maximum value of the differential coefficient in a region exceeding the upper threshold value and a minimum value of the differential coefficient in a region smaller than the lower threshold value. The arithmetic operation unit binarizes the detection signal by using the maximum or minimum value as a leading or trailing edge of a binary function.

A single light emitted from a laser source is split into multiple beams. The multiple beams are illuminated by a multi-beam scanner to scan a substrate of interest. An optical system is provided for focusing the multiple beams independently on the substrate and directing a reflected light or a transmitted light of the multiple beams on the substrate. Aperture regulating members are disposed at equal intervals corresponding to the interval between the multiple beams for controlling the multiple beams directed from the substrate by the optical system. The multiple beams passed through their respective aperture regulating members are received by an optical detector assembly which detect a change in the amount of the multiple beams. The substrate is continuously moved by a movable table on a plane substantially vertical to the multiple beams and in a direction arranged at substantially a right angle to the scanning direction of the multiple beams. Then, a scanned image is produced by an image processor from a signal output of the detector assembly and data of the coordinate location of the movable table and compared by a comparator with a corresponding reference image.

Optical substrate inspection apparatus

A magnetic material with an improved maximum energy product useful for high performance permanent magnet, bond magnet and other applications is disclosed. The magnetic material is expressed in a general formula R1.sub.x R2.sub.y M.sub.100-x-y where R1 is at least one element selected from the rare earth elements, R2 is at least one element selected from elements having an atomic radius in a range of 0.156 to 0.174 nm, M is at least one element selected from Fe and Co and x and y are atomic percent individually defined as x.gtoreq.2, y.gtoreq.0.01 and 4.ltoreq.x+y.ltoreq.20, and M occupying 90 atomic percent or more in the principal phase of the compound.

Magnetic material

Growing community of inventors

Nagareyama, Japan

Hideo Nagai