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LightConnect Comes Into Bloom

Another instance of two startups basing developments on the same fundamental innovation emerged today when LightConnect Inc. announced its first products (see LightConnect Launches First Products).

LightConnect is making telecom components using MEMS (micro-electro-mechanical systems) technology developed by David Bloom and Asif A. Godil of Stanford University. And guess what? So is Silicon Light Machines, a startup acquired by Cypress Semiconductor Corp. (NYSE: CY) last year (see Cypress Flexes MEMS Muscles).

Bloom and Godil were founders of both startups. Their original idea was to pursue display applications with Silicon Light Machines and telecom applications with LightConnect, according to Bloom.

Cypress, however, now appears to be on a collision course with LightConnect. Having sewn up a deal with Sony Corp. covering its original display components, it's shifted tack and is busy developing telecom components similar to the ones announced by LightConnect today.

This sort of thing has happened before. Kestrel Solutions Inc. and Centerpoint Broadband Technologies Inc. both based their frequency-division multiplexing developments on technology invented at Lockheed Martin Corp. (see Battle Begins Between FDM Twins). Last year, Lockheed Martin also spawned a couple of competing startups developing parallel optics -- TeraConnect Inc. (see Lockheed Spins Off Transmitter Startup) and Xanoptix Inc. (see Xanoptix's Strange Story).

So now LightConnect and Cypress are going head to head, and for the moment, at least, it looks as though LightConnect is out in front on a couple of counts -- having actual products and actual customers.

Both LightConnect and Cypress are basing their developments on MEMS structures that resemble miniature xylophones.

In Cypress's case, a bunch of ribbons are stretched side by side over a shallow trench. When no voltage is applied, the ribbons form a flat mirror, simply reflecting whatever light is shone on them. When voltages are applied, alternate ribbons are pulled down by tiny amounts and the reflections from the different surfaces intersect to form interference patterns or Bragg gratings -- a fundamental building block for all sorts of optical components.

LightConnect's developments work in a similar way, except that there's no regular array of ribbons and the alternate surfaces are kept one wavelength apart before voltages are applied. This creates "constructive interference," according to Peter O. Clark, LightConnect's president and CEO. When a voltage is applied, the top surface is pulled down by a maximum one quarter of a wavelength -- a matter of a few microns -- creating "destructive interference" or the Bragg gratings mentioned previously.

"It's a much more complicated structure," says Clark. The upshot, he contends, is that LightConnect's components are wavelength and polarization independent, while Cypress's aren't. "We've developed significant IP [intellectual property] of our own," says Bloom, noting that his links with Silicon Light Machines ended with its acquisition by Cypress.

Cypress wasn't able to find anybody to comment on this at press time.

In other respects, both companies share the advantages of the xylophone approach. Very small movements are needed to make these devices work, which means that they can switch from one state to the other very quickly. LightConnect cites response times of 50 to 60 microseconds for the products it announced today.

The small movement also means the MEMS structure isn't subjected to much stress. “We’re very confident about the long-term reliability," says Clark.

Another big plus for both companies is that the MEMS structure is made using existing equipment in CMOS (complementary metal oxide semiconductor) foundries. This explains why Supertex Inc. (Nasdaq: SUPX) is an investor in LightConnect: LightConnect is using Supertex's CMOS foundry to make its products.

As noted, LightConnect appears to be further ahead in developing its telecom components. The products it announced today -- a variable optical attenuator (VOA), a multiple channel VOA, and a dynamic gain equalizer -- are already being shipped to four customers, three of which are publicly quoted system vendors, says Clark: "It's more than samples. These things are being built into their systems."

The VOAs are much smaller and faster than others currently on the market, according to Clark. They're “the optical analog of transistors," he says. They’ll be “sprinkled” throughout DWDM (dense wavelength-division multiplexing) networks to control the optical power in adjacent channels in a variety of equipment.

LightConnect’s dynamic gain equalizer will do a similar job in EDFAs (erbium-doped fiber amplifiers) and Raman amplifiers. It differs from other products in being dynamic. It’ll form part of a feedback loop that’ll continuously adjust the power in different channels to optimize overall network performance.

Testing of these products to make sure they comply with Bellcore standards will be complete in August, Clark adds.

In comparison, Cypress has yet to announce telecom product details, and analysts aren't expecting it to start shipping until mid 2002.

LightConnect raised $8.4 million of Series A funding in June 2000 from Sevin Rosen Funds, U.S. Venture Partners, Morgenthaler Ventures, Intel Capital, Optical Capital Group, Supertex, and Milton Chang and his incubator company, Incubic LLC (see Chang's Investment Shop).

LightConnect hopes to be able to announce closure of a second round of financing at the NFOEC next week. The amount hasn't been disclosed.

— Peter Heywood, Founding Editor, Light Reading
http://www.lightreading.com
redface 12/4/2012 | 8:08:45 PM
re: LightConnect Comes Into Bloom Thanks for the tip.
spin1 12/4/2012 | 8:08:46 PM
re: LightConnect Comes Into Bloom OMM is wrong. most surface micromachined devices with electrostatic actuation *require* hermetic packages for reliabiltiy; bulk micromachined devices with electromagnetic actuation do not unless the environment conditions are really severe such as sub freezing or condensing humidity.
heydinger 12/4/2012 | 8:08:54 PM
re: LightConnect Comes Into Bloom All of LIGHTCONNECT's Diffractive-MEMS chips are hermetically packaged. During manufacturing, 100% of the packages are tested for hermeticity.

LIGHTCONNECT's Diffractive-MEMS chips are based on standard CMOS manufacturing processes. They have already passed billions of attenuation cycles without any degradation in performance.
redface 12/4/2012 | 8:08:55 PM
re: LightConnect Comes Into Bloom LightConnect's products are based on MEMS. According to OMM, all MEMS structures require hermetic packaging. So are LightConnect's products hermetically packaged?

These MEMS seem to be based on polycrystal silicon. Anyone has any idea about the reliability of polycrystal silicon MEMS structure?
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