Site: Furukawa Electric Co.
Optotechnology Laboratory
6 Yawata-Kaigandori, Ichihara
Chiba 290, Japan

Date Visited: December 12, 1994

Report Author: G. Day



G. Day
P. Shumate


Dr. Naoya Uchida
Director, General Manager, Optotechnology Lab.
Shintaro Sentsui
General Manager, Development and Engineering Dept.
Haruki Ohgoshi
Manager, Optical Transmission System Research
Dr. Shoichi Ozawa
Manager, Optical Integrated Circuits, Development and Engineering Department


Furukawa Electric Company was founded in 1884. It employs about 10,000 people and has sales of about $5 billion/year. Cable is the main product, at 56% of sales. Aluminum (20%) and copper and related products (10%) are the next largest categories. Other significant product areas include plastics, superconductors, information equipment, and GaAs wafers.

Furukawa operates 7 laboratories, with a staff of 850 and budget of $150 million (3% of sales). The JTEC team's hosts described activities at six of these: Optotechnology Laboratory, Information and Electronics Laboratory, Yokohama R&D Laboratory, Chiba Research Laboratory, Hiratsuka Research Laboratory, and Nikko Research Laboratory. The main items of R&D interest are materials, power and energy, optoelectronics, telecommunications, and electronics. In addition to the Optotechnology Laboratory, two other laboratories are concerned with optoelectronics. The Information and Electronics Laboratory conducts research on optical links and optical transmission systems. The Yokohama R&D Laboratory conducts research on laser diodes, LEDs, and photodiodes.


The Optotechnology Laboratory has a staff of 150 out of a total of 2,000 Furukawa employees in Chiba. It conducts research on optical fiber, optical cables, optical devices (connectors, fiber devices, and SiO2:Si waveguide devices), optical equipment and systems (fiber amplifiers, equipment for construction and maintenance, equipment for link operation and inspection), and other topics (metallic cables and materials for cables).

Two paths for new product development were described. One results from a direct Business Department order based on the interest of a specific customers. The other arises as an R&D proposal that first goes to the business department for agreement, then funding. The lab depends primarily on customers' market studies rather than conduct any of its own.


Ten product areas were discussed in detail:

High-Count Optical Cable

One thousand fiber cable with a diameter of 30 mm and 4,000 fiber cable with a diameter of 40 mm represented the state of the art at the time of the JTEC visit.

Dispersion Compensation Fiber

Dispersion of -85 ps/nm km, mode field diameter of 5 microns, and attenuation of 0.4 dB/km are values consistent with those of other manufacturers. However, the use of such fiber for dispersion compensation requires a compensating fiber to be about 20% as long as the transmission fiber, so that there is a need for alternative compensation fibers or devices.

Carbon-Coated Fibers

Fibers are coated with carbon for improved strength and water resistance.

Sensor Fiber

The laboratory demonstrated offset core designs for evanescent field sensing. The targeted application is methane sensing. Present sensitivity is 1 dB/ 20 mm in 50% methane environment and 2 dB/20 mm in 100% methane (atmospheric pressure).


Laboratory representatives discussed various connector designs.

Inline Filters

Another product consists of dielectric coatings on thin glass, inserted between fibers lying in Si v-grooves.

Planar Waveguide Devices

This is an area of growing interest for Furukawa; the technology is based on NTT work, but pursued independently, without collaboration. Couplers are SiO2 on Si, produced by flame hydrolysis. 1 x 8 couplers have been transferred to Fitel Products Division in Urayasu and are commercially available; excess loss is 1 dB. 1 x 16 couplers are under development. Both active and passive alignment technologies are presently being used, though passive techniques are desired for low-cost manufacturing. Present manufacturing capacity is 100 devices/month. At present, the cost of a 1 x 4 waveguide coupler is comparable to that of a fiber coupler. Waveguide couplers become more competitive as the splitting ratios increase; they are also smaller than fiber devices for equivalent ratios. The company also has a Mach-Zehnder wavelength-insensitive directional coupler under development that operates from -40 to +85 deg. C with only 0.2 dB change in coupling.

Pump Lasers For EDFAs

Yokohama Laboratories produces 980 nm chips and supplies on carriers for assembly in Chiba. The package includes two molded glass lenses: an asymmetric spherical collimating lens before the isolator, and an aspheric lens to focus light into the fiber. They achieve lifetimes of 1 Mh at 25 deg. C, maintained with a thermoelectric cooler.


EDFAs are commercially available through Fitel Products Division.

Video/ISDN Distribution System

The video/ISDN distribution system supplies ISDN at 1310 nm and video at 1550 nm. There are 11 channels of AM video and 50 channels of FM video. A series of 1 x 16 splitters and amplifiers yields 5,488 channels for a single laser source. The key technologies making this possible are the optical fiber amplifier, the optical waveguide splitter, and dispersion compensating fiber. A prototype system is now being tested in a field trial in Keihanna.


Technology is usually transferred, along with the technology, to a production division (e.g., Fitel) by transferring staff. Furukawa maintains a Plant and Facilities Department, consisting of about 100 people, which specializes in the development of manufacturing systems and automation. It has capabilities in mechatronics (micromechatronics, micromachining, and robotics), manufacturing line construction (line automation, new manufacturing processes), and sensing systems. This division collaborates with research lab personnel in establishing manufacturing capabilities.


Furukawa brochures on the Optotechnology Laboratory and the Chiba Works; technical descriptions and specifications on the PLC (planar lightwave circuit) Technology and the EDFA; and a description of Keihanna field trial.

Published: February 1996; WTEC Hyper-Librarian