Entry for April 23, 2006

The above illustration comes from University of Arizona.  Dr.  Guoqiang Li and Dr. Nasser Peyghambarian of The College of Optical Sciences have invented switchable focus optical lenses, just reported in the April 18 edition of the Proceedings of the National Academy of Sciences.  

The lenses will be manufactured right her in Roanoke, Virginia by Pixel Optics which bought the patent from Johnson and Johnson,  original funder pf the research.  Senior management includes optometrist Ronald Blum, originally with Blum, Newman and Blackstock (now just Newman-Blackstock in Radford and Lexington.  Another senior manager at Pixel Optics  is Dwight Duston, Ph.D., former head of R&D for the U.S Strategic Defense Initiative, i.e. “Star Wars.”  

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Blum founded Innotech in 1990, took it public on the NASDAQ in 1996 and sold it to Johnson and Johnson in 1997 for $115 million.  There he led the team within J&J known, first known as the Innotech Division and later  as the Spectacle Lens Group, which invented the Definity Lens acquired by Essilor, which proceeded to close the Roanoke plant.

Earlier,  nine eye care ompanies had sued Johnson and Johnson, according to a September 12 story by Roanoke Times reporter Tad Dickens.  alleging Johnson & Johnson Vision Care Inc. had abandoned its commitment to the Excalibur System a lens-making technology, first manufactured in 1993 by Innotech.  Since the early 1990s, Innotech  had promised customers

 it would help market and maintain the machines…and also promised to sell Excalibur customers the machine parts needed to make the lenses [and that]  in about seven to 10 years, the $15,000 to $20,000 machines would pay for themselves…Company officials had told its Excalibur customers that Johnson & Johnson would sink millions into the machines after it bought Innotech

The promises turned out to be so much snake oil. 

Johnson & Johnson told its Excalibur customers in February 1999 that another company would sell some of the parts to eye care businesses through the end of that year. On March 31, 1999, Johnson & Johnson “ceased all support” and “stopped the manufacture and supply” of the machines, according to the suits. .. Johnson & Johnson had set up a reimbursement system for Excalibur owners. That system was pro-rated….Those who had owned it for three years or more would get $2,000.

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While the glasses are pretty clunky, what interested me are the future plans for contact lenses, if the promises are more factual than those for Excalibur or Star Wars.

In the future it may be possible to fit pixelated contact lenses that focus dynamically and will allow a wearer to focus far, near or in between. This would solve the current visual problems associated with contact lens bifocals or multifocals. It should be noted that significant additional research and development is needed before this can become a reality. (One patent has issued and another is pending.)

As someone who suffers from early onset cataracts,  probably due to radiation treatment, I was even more interested in the possibility of a better intra-ocular lens.  Current replacement  lenses  a deal with the devil.  Keep your own lenses which adjust but are flawed, or get  onces that allow you to see perfectly, but at only one fixed point. 

It may also be possible to replace a dysfunctional human crystalline lens with a fully dynamic pixelated intra-ocular lens. This would allow for dynamic focusing of far, near and in between. In addition, it could allow for post-surgical remote tuning of the prescription. Also, there are very promising indications that this technology may allow to remotely focus / steer an image from a diseased or damaged retinal location to a healthy portion of the retina, thus helping individuals with Macular Degeneration see better. (Several patent applications are pending.)

Wow! 

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 How do these things work?  According to an April 3 article  by UA’s senior science writer Lori Stiles,

They are basically two pieces of flat glass spaced five microns apart. Five microns is an incredibly small space — roughly one-twentieth the diameter of a human hair. The space is filled with liquid crystal — the same kind of stuff in your laptop’s liquid crystal display.

The flat glass is coated with an even thinner layer (one-tenth micron) of indium tin oxide, or ITO, which is a transparent electrode. Unlike electrodes made of aluminum or gold, ITO transmits most of the light that hits it.

The transparent electrodes are patterned in a circular array over the area of the lens. The circular pattern is created through photolithography, an extremely precise technique that processes with light and chemicals.

Applying less than two volts to the circuit changes the orientation of the liquid crystal molecules, and that changes the optical path length through the lens. It takes only about 1.8 volts to change the index of refraction so that light refocuses, Peyghambarian and Li explained. The result is a flat piece of glass that acts like a lens.

 

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