The Furukawa Electric Co., Ltd.

Yusei Shirasaka

Kenichi Fuse

Toshio Kimura

Masayuki Iwase

Takeshi Aikiyo

Haruo Umezu

A semiconductor laser module comprising a lens system having first and second lenses for coupling a beam emitted from a semiconductor laser with a core expanded fiber having a single-mode fiber end whose core diameter is expanded. The core expanded fiber is set so as to have a core expansion coefficient of 1.3 or more and an absolute value of change rate of mode field diameter smaller than 6.0.times.10.sup.-4 .mu.m.sup.-1.

Semiconductor laser module

A laser diode array device (1, 11) according to a first aspect of the invention comprises a plurality of laser diode elements, some of which are formed as monitor laser diode elements for controlling the optical output of the remaining laser diode elements so that the device can operate at a power consumption rate by far lower than that of a conventional laser diode array device where the component laser diode elements needs to be individually controlled, while it can be assembled to an enhanced density. A laser diode array device (21) according to a second aspect of the invention comprises laser diode elements for signal transmission and monitor laser diode elements realized in the form of resonant cavities having a same length and sharing a common reflecting surface of a high-reflection film disposed at an end thereof so that the laser diode elements for signal transmission and the monitor laser diode elements show substantially identical light emitting characteristics.

Laser diode array device

Coated optical fiber cable structure which prevents longitudinal cracks

A method of exfoliating the coating of a coated optical fiber is described. A crack in the coating layer of the optical fiber is produced by bending means, cleaving the coating into a plurality of cleaved strip pieces while longitudinally enlarging the crack, and then cutting the strip pieces with an advantageous exfoliating tool. The exfoliating tool thus used is constructed to conveniently cleave the coating layer of the optical fiber and to cut the cleaved strip pieces. It does not damage the optical fiber upon exfoliating of the coating layer from the coated optical fiber, and can efficiently exfoliate the coating of the optical fiber.

Growing community of inventors

Ichihara, Japan

Yusei Shirasaka