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Fujitsu Introduces World's First DP-QPSK LN Modulator for 100Gbps Optical Networks

September 14, 2009

- Compact-sized modulator with low drive voltage for use in commercial systems -

Kawasaki, Japan, September 14, 2009- Fujitsu Optical Components Limited today announced the development of the compact DP-QPSK (*1) LN modulator (*2) with low drive voltage for next-generation 100Gbps optical networks. The product makes it possible to construct commercial systems with high reliability, low power consumption, and superior transmission quality. It will be available starting December 1st, 2009.


In recent years, the expansion of new services such as cloud computing and on-line streaming has brought about a dramatic increase in data communications. As the data transmission volume of communications networks rises, R&D activities related to the commercialization of next-generation 100Gbps optical networks have gained significant momentum. While many optical transmission signal encoding methods are under consideration, DP-QPSK transmission technology is becoming essential due to its high tolerance against signal distortions resulting from transmission fibers and relay nodes, its superior bandwidth efficiency, and its increasing transmission capacity achieved without increasing symbol rate. Moreover, this transmission technology is being standardized by OIF (*3).

There has been growing demand for compact, low drive voltage, and wide bandwidth optical modulators required for the construction of commercial optical network systems. However, achieving these capabilities has been a major challenge for DP-QPSK compatible modulators, due in part to their complicated structures.

Fujitsu Optical Components has developed the technology to overcome this challenge, and has succeeded in producing a compact DP-QPSK LN modulator with low drive voltage for use in commercial optical network systems.

Key Features

1. Compact LN modulator with DP-QPSK circuits integrated inside a single package
The DP-QPSK modulation optical circuit and polarization beam combiner were integrated inside a single package, making the compact LN modulator suitable for 7" x 5" transponder.

2. Wide bandwidth and low drive voltage (maximum 3.5V)
In order to generate high-quality DP-QPSK signals, it is necessary to expand the optical bandwidth of a modulator. To transmit DP-QPSK signal with data rate of 100Gbps, modulation rate of 25Gbps is required. By using technology similar to that employed in previously commercialized 40Gbps LN moderators, a wide bandwidth of 25 GHz was achieved.

In addition, this LN modulator has low drive voltage of maximum 3.5V, making it a practical optical modulator for use in commercial systems.

3. User-friendly interface
By positioning multiple RF signal input terminals close to each other at one side of the modulator, DP-QPSK signals can be generated without the need to adjust for the time delay between electrical signals on the drive circuit.

Additionally, by employing separate input terminals for the RF signals mentioned above and the DC bias signals for modulator control, the need for an external electrical circuit to combine the two types of signals was eliminated.

Pricing & Availability

Product Name Pricing Shipment
100G DP-QPSK LN Modulator Quoted per order December 1st, 2009

Sales Target

  • 500 million yen in fiscal 2010
  • 1 billion yen in fiscal 2011

Additional Information

Glossary & Notes

(*1) DP-QPSK
Acronym for Dual-Polarization Quadrature Phase Shift Keying. It is a method of phase modulation for digital signals, in which 2 bits of data are allocated to each of 4 modulated optical phases (0°, 90°, 180° and 270°) for both P-polarized light and S-polarized light.

(*2) LN Modulator
A device that converts an electrical data signal into an optical data stream via the electro-optic effect of a LiNbO3 crystal. Intensity modulators convert input electrical signals to optical intensity signals, while phase modulators convert them to optical phase signals. One of the LN modulator's features is modulation with minimal wavelength chirping. This is a desirable characteristics for ultra high-speed, long haul, and DWDM (Dense Wavelength Division Multiplexing) transmission.

(*3) OIF
Acronym for Optical Internetworking Forum. The OIF is an organization that promotes the standardization for interface between IP router in data networks and WDM (Wavelength Division Multiplexing) equipment in optical networks.

Press Contacts

Fujitsu Limited
Public and Investor Relations Division

Customer Contacts

Fujitsu Optical Components Limited
Sales & Business Development Division
Marketing & Business Development Dept.
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About Fujitsu

Fujitsu is a leading provider of IT-based business solutions for the global marketplace. With approximately 175,000 employees supporting customers in 70 countries, Fujitsu combines a worldwide corps of systems and services experts with highly reliable computing and communications products and advanced microelectronics to deliver added value to customers. Headquartered in Tokyo, Fujitsu Limited (TSE : 6702) reported consolidated revenues of 4.6 trillion yen (US$47 billion) for the fiscal year ended March 31, 2009. For more information, please see:

About Fujitsu Optical Components

Aiming to strengthen Fujitsu's optical module business, Fujitsu Optical Components was established on April 1st, 2009 as a wholly owned subsidiary of Fujitsu Limited. With the establishment of the new company, the sales, research and development, and manufacturing functions of Fujitsu's optical module business are integrated under a unified management structure. Headquartered in Kawasaki, Japan, Fujitsu Optical Components is a leading supplier of the most advanced, high-reliable and customer-focused optical components for datacom and telecommunications applications in the global market. Its broad products line-up includes DWDM pluggable transceivers, full-band tunable 300pin transponders, G-PON transceivers and 40G/100G LN modulators. The company also plans to provide the most advanced 40G/100G integrated receivers in the near future. For additional information, visit

All other company or product names mentioned herein are trademarks or registered trademarks of their respective owners. Information provided in this press release is accurate at time of publication and is subject to change without advance notice.

日付: 14 September, 2009