Thanks for pointing them out Frank. I found this other bit of press--which is actually quite old--where their description of their devices seems to fit pretty well with the lambda classes model (Ahhaha, I haven't forgotten; I still owe you a reply about said model).
Now I just need to fill in the gaps between 7/97 and today and see whether they're still on the same course.
here's the article:
STREAMLINING THE SHORT-HAUL Multichannel News, July 21, 1997 p85
Technology Promises Cheaper Multiwave Carriage
FRED DAWSON
A new firm making use of specially made graded-index glass is preparing to introduce optoelectronic components that it hopes will help to drive down the costs for implementing short-haul multiple-wave-length technology.
LightPath Technologies Inc., supplier of Gradium glass, and Invention Machine Corp., a network-design and software-engineering concern, have teamed up to form LightChip Inc. The intent is to deliver devices mapped to a universal design that can be customized to support a variety of dense-wave-division multiplexing applications, including cable TV, fiber-to-the-home and all-fiber local-area networks.
'Our first units, which will be for a LAN-type application, will be available for beta trial sometime in the first quarter,' said Paul Dempenwolf, director of optoelectronics-product development at LightPath, which is based in Albuquerque, N.M.
Dempenwolf said the new integrated components would allow LANs to feed dedicated wavelengths to different categories of end-users, and to convert those wavelengths to electronic signals, at a cost of about $200 per connection.
Today, the costs of doing this would be in the thousands of dollars, which is why DWDM applications in the LAN environment are limited to experimental networks operating at the Massachusetts Institute of Technology and other high-tech centers.
'We intend to deliver products for cable and telephone-loop applications with the same costs per [wavelength] switch port,' Dempenwolf said. 'This applies to the loop ports, as well' - which are the points at which public networks interface with private or other public networks.
The creation of LightChip follows by a few weeks an agreement between LightPath and Eagle Optoelectronics Inc. of Boulder, Colo. That deal called for the development of low-cost, high-performance transmitter/receivers. These would be integrated with the wavelength multiplexer/demultiplexers developed by LightChip to support the optical-to-end-user wavelength selection and conversion within a single component.
'The technology supports the use of very cheap lasers by canceling out all cross-talk and detecting only the primary signal,' Dempenwolf said, contrasting this approach with long-haul DWDM applications, where lasers tightly specced to specific wavelengths add significant costs to the system.
The use of Gradium, which precisely disperses or concentrates wavelengths through gradations in the index of refraction across the diameter of the glass component, allows for low-cost integration of the receiver into a circuit board, he said.
The initial, four-wavelength LAN components will be followed by components for short-haul applications in cable and telephone networks, using the same basic design principles, Dempenwolf said. 'We want to go to cable engineers and other customers with a working product, rather than trying to get them to support a concept, so we're investing a lot upfront to get real, working devices into production,' he added.
The move by LightPath and Invention Machines reflects growing demand in short-haul telecommunications markets for DWDM solutions that avoid the high costs of long-haul applications while achieving the same types of gains in capacity and all-optical functionality.
A proprietary study issued by a consulting firm that works closely with major telcos sees the DWDM short-haul market growing to $200 million in 1998, $450 million in 1999 and into the billions of dollars from there, according to one recipient of the research, who asked not to be named.
The sudden interest among telcos and cable companies in DWDM networks has prompted another start-up, Light-wave Microsystems (LMC), to shift gears in its preparations to bring new, polymer-based DWDM-component products to market.
Earlier this year, the company said it would bring a wavelength multiplexer/demultiplexer targeted to long-haul applications to market sometime in the second half. But a need for very fast changes in network routing in short-haul applications to protect against outages has prompted the firm to focus on the development of a two-by-two optical switch that operates at speeds over 40 gigahertz, said George Ballog, senior vice president of LMC.
Along with low-cost demultiplexer/receivers such as what LightPath and its partners are developing, the optical-switching segment of DWDM networking is vital to the shift of the technology into the short-haul market. Together, the two companies' approaches tend to vindicate projections such as the one that telecommunications consultant Earl Langenburg recently made that FTTH will become cost-effective for new-builds within the next year or so.
'We initially were focused on optical switches and then, when DWDM got hot in the long-distance market, we shifted to putting the priority on the multiplexer,' Ballog said.
'Now, with the interest that we see in the short-haul market, we think that there's a bigger opportunity for an integrated optoelectronic switch.'
The first generation of product will be devoted to the rerouting challenge, where local-traffic capacity and budget requirements won't tolerate the buffering techniques that are used in long-distance DWDM networks to compensate for the effects of slow switching. But the way in which the switches are fabricated will lead quickly to switches that are true add/drop multiplexers capable of routing multiple wavelengths.
LMC uses a class of polymers known as 'polyimedes,' developed in conjunction with Hitachi Chemical Co., to overcome the thermal and loss problems that have limited the use of polymers in light-wave communications. Fabrication entails etching of 3-micron 'trenches' in silicon - a much lower-cost process than today's 0.35-micron, state-of-the-art circuit fabrication and then adding the polymer at high temperature, forming a core matching single-mode-fiber dimensions.
In order to facilitate development of integrated optical switches, LMC has come up with a way to make the wave guide reactive to electronic impulses generated from circuits in the silicon substrate below the polymer trenches. This is done by doping the polymer with materials known as 'chromophores.'
'There's a deep polarity sensitivity in the dopant so that when you apply voltage, you cause the index of refraction in the polymer core to shift, creating a switching mechanism,' Ballog said. |