Technology Bulletin 484

Nanotubes come to flat-screen TV

A Swiss research team is using tiny carbon cylinders, called "nanotubes," for flat screens for TVs or computers. A team headed by physicist Walter De Heer at the Lausanne Polytechnic Federal Institute of Technology discovered that millions of nanotubes coated on film perform better, at less expense, than a cathode ray tube in a TV. A report in Science said the nanotubes might provide the first good substitute for the large electron guns that create a CRT's color picture by firing a beam of electrons at a display screen coated with color phosphors. De Heer's team has produced 0.5-inch-thick screens as large as several hundred square centimeters. The screens require no warm-up and have the advantage of providing their own illumination, say researchers. "Upscaling is immediately possible because the nanotube films can be made arbitrarily large," reports De Heer. For details, e-mail him at [email protected] .

Enter your design now for the R&D 100 Awards

R&D Magazine is accepting entries for its 1996 R&D 100 Awards program through March 18. The program honors the most technologically significant products, processes, and software introduced to the market during 1995. Winners will be honored at a banquet on October 14 in Philadelphia. Entries can be ordered by fax at (708) 390-2618, via email at [email protected] or by calling (708) 390-2734. The magazine is also looking for judges. If you are an acknowledged expert in your field and can devote 10-20 hours to this interesting task, please forward your resume to Tim Studt, R&D 100 Awards, 1350 E. Touhy Ave., Des Plaines, IL 60018.

Optical data-storage system uses a hologram medium

An electro-optical device developed at US FAX Inc., Philadelphia, could influence the way large stores of data are processed. The technology may be applied to the transmission of virtual reality and image data, as well as database storage and retrieval. US FAX engineers recently filed for patents of the holographic data optical storage system. One patent would cover a read-only "holo" multi-CD which could be used to store several full-length motion pictures on a product the size of a conventional CD. Another patent would cover "mega-memory" crystals for data-storage devices able to access digital information at the speed of light. The electro-optical device, called a Read-Right(TM) Light Array, includes multiple laser emitters and optical sensors and eliminates the need for ultra-precision positioning via mechanical devices, claim engineers. The arrays are positioned on each side of the hologram medium and the multiple data sites are accessed using an optical switching network that can operate far faster than any rotating disc. The hologram stores millions of bits of binary data as black or white squares that resemble crossword-puzzle pages. Unlike conventional magnetic storage products that process bits of data one at a time, the new device enables pages to be read simultaneously. For more information, call US FAX at (800) 329-1517.

Process tempers ceramics to prevent cracking

Materials scientists at Cornell University, Ithaca, NY, have developed a process that they hope will temper high-temperature ceramics and prevent cracking. The process shows potential for a new generation of materials for application in jet turbines, where components are subjected to high temperatures and loads for long periods. The method mimics glass tempering by imposing a compressive stress on the outer surfaces of the ceramic to prevent cracks from propagating. To do this, the researchers bonded alumina (a ceramic compound of aluminum and oxygen) to nickel aluminate, another ceramic compound. They then reduced the nickel aluminate by removing oxygen, which decreases its volume and imposes compressive stresses in the outer surfaces. Cornell has applied for a patent on the process, but materials science and engineering professor Stephen Sass cautions that it is not yet ready for commercial application. For details, FAX Sass at (607) 255-2365.

Optical probe to speed cervical-cancer tests

Women often wait weeks and must undergo additional tests to confirm the results of an abnormal Pap smear, a test used to screen for cervical cancer. Now, a fiber-optic device being developed at the University of Texas Anderson Cancer Center, Houston, provides immediate and non-invasive results for the detection of precancerous cervical tissues. The prototype is the result of a cooperative effort between Sandia National Laboratories and LifeSpex Inc., Houston. It takes advantage of differences in the way normal and abnormal cervical tissues absorb and emit light. Optical fibers at the end of a small probe illuminate the tissue of the cervix and collect the fluorescent light that is generated. Precancerous cells will fluoresce differently than healthy tissue. The new test would allow doctors to conduct further examination and treatment in the same visit if abnormalities are detected. The technique, called "tissue spectroscopy," could be used as a non-invasive test for cancer in other tissues, and also shows potential for battlefield hospitals to detect chemical or biological agents. For details, e-mail LifeSpex at [email protected] or project leader David Sandison at [email protected] .