Plastic components subjected to vibration and bending can crack beyond repair, creating difficulties in applications where components are largely inaccessible after final assembly. But researchers at the University of Illinois may have found a solution for plastic fatigue. Their self-healing polymer automatically repairs cracks in the plastic as they occur. According to findings reported in Nature magazine, the polymer material regains up to 75% of its original ruggedness after self-healing occurs. Its material structure contains tiny capsules of polymer building blocks known as monomers. A catalyst causes these monomers to link together and form polymeric chains and networks. Cracks in the polymer cause the embedded capsules to break and release the monomers. Once in the catalyst's presence, these monomers form bonds between the fracture faces. This polymer bodes well for the electronics industry, which aims to lower component cost by moving from ceramic and other high-performance packaging materials into lower-cost plastic versions.
A research grant awarded by the National Science Foundation will support NanoSciences Corp. in its efforts to develop a new class of low-threshold, high-efficiency microlaser arrays. The work will center around the company's nanomaterial fabrication technology. In Phase I of the program, NanoSciences will explore the fabrication and characterization of nanochannel materials while seeking to incorporate the photonic crystal into them. The second phase will attempt to design the laser's structure and measure its efficiency. The microlaser arrays promise easy integration into silicon-based photonic devices, making them candidates for use in telecommunications equipment, displays, laser printers, and optical integrated circuits.
Physicists at IBM-Almaden have demonstrated a specially patterned magnetic medium that achieves data storage densities up to 100 Gbits/in2. For this, scientists used a focused ion beam to cut into the magnetic material and create isolated magnetic islands. By making these islands smaller than 130 nm, researchers ensured that each would have only one magnetic domain, corresponding to one bit of information. The domains were large enough to be thermally stable even when areal bit density was very high. The issue of thermal stability is one of the challenges facing existing disk-drive technology. Currently, steady increases in data storage density have been obtained by shrinking the size and number of magnetic grains needed to store a single bit of data. So far, that has extended disk-drive technology to about 20 Gbits/in2. Further gains are expected. IBM's findings were reported by the American Institute of Physics in its online publication, Physics News Update.
The wavelet group in the department of applied science at the Lawrence Livermore National Laboratory (LLNL) is studying signal processing using the wavelet transform. A relatively new mathematical tool, the wavelet transform has proven useful in the analysis of various types of signals, from 1D speech, biomedical, and seismic signals to 2D images. A key property is its ability to locate short-time, high-frequency features of a signal and at the same time resolve low-frequency behavior. This constant-Q type of analysis suits "real-world" phenomena very well. LLNL's research is targeting electrocardiogram compression, seismic signal feature extraction, and feature-based wavelet design.
Sharp's improved TFT LCD technology, ASV (advanced super view), has a 170° viewing angle horizontally and vertically, with response time confined to 25 ms or less. Competitive TFT LCD technologies offer response times between 80 and 150 ms. With such a short response time, ASV becomes a strong candidate for full-motion video. Other benefits include the total elimination of bright pixel defects that can be annoying artifacts when a TFT LCD is used in the black mode. Sharp plans to convert much of its TFT LCD production to ASV over the balance of this year. Products incorporating this technology will come along shortly.