Home > R & D > R & D Review

R & D Review

No.109 September 2012

Development of Multi-core Fiber and Fan-in/Fan-out Device

We report the development of the multi-core fiber and fan-in/fan-out device that support the next generation optical communication in this report.
3 kinds of multi-core fiber (step structure, barrier layer structure, trench structure) were fabricated, and the relation between the crosstalk and optical fiber structure were shown.
We fabricated the multi-core fiber with polygon clad for the connection by the connector.
The fan-in/ fan-out device with the hexagonal close-packed structure was fabricated by using the small diameter fiber and the high precision ferule.
We confirmed that these devices had the alignment position of core of ± 1mm within accuracy.
〔Key words〕 Multi-core Fiber , Crosstalk, Fan-in, Fan-out

Development of Yb Doped Double Cladding Fiber with High Reliable Polymer Cladding

We developed Yb doped polymer double cladding fiber that has the large numerical aperture( NA) of pump guide over 0 .5 and the excellent endurance for high temperature and high humidity. There was no change of the NA of pump guide even under the condition
of the high temperature (>120 deg.) / the high temperature and high humidity (80 deg. × 85%). We confirmed that NA of pump guide is kept constant at the length over 50 m by optimization of the production condition. We improved the damage resistance to photo darkening by optimization of the core composition. And 74 W output was obtained at the pump power of 118 W with conversion efficiency of 63 % by using the double cladding fiber with 60 m length.
〔Key words〕 Ytterbium, Double Cladding Fiber, Polymer Cladding, Endurance, Photo Darkening

Development of High Power Laser Delivery Fiber
- Development of High reliable connector technology -

In the present report, we introduce about the high reliability connector technology to support the high-power laser transmission technology which can be looked for in the laser machining field. The End Cap technology and the cladding mode rejection technologies are the key technology to improve the reliability of the connector for the laser transmission substantially. We developed the connector for the high-power laser transmission which loaded with these technologies and evaluated the resistance for the cladding mode power.
As a result, we confirmed the temperature of the connector can be suppressed to 60℃ or less even at over spot input power of 250W or more.
〔Key words〕 Laser Delivery Fiber, High Power Laser, EndCap, Mode Stripper, Cladding Mode

Development of A New Type of All-in-one Partial Discharge Detector B010

Conventionally, a partial discharge measurement has been carried out for high voltage devices such as electric devices or power cables to evaluate the insulation performance.
In addition, recently, high insulation performance is required also for low voltage products
such as power module ICs, printed-circuit boards, low-voltage motors, and insulated films of back sheets of the solar battery, and there is a growing need for the partial discharge measurement. To test these low voltage products, a compact partial discharge detector which can flexibly control the voltage is best suited.
We have developed and will introduce a new type of all-in-one partial discharge detector using a low-frequency method, which controls the test voltage pattern by electronic control which enables more flexible test voltage control instead of control by a motor, and we can evaluate the insulation performance by simple operations with a PC.
〔Key words〕 Partial Discharge, Insulato

Back to Top