Period: August 4 - 11, 1996 (8 days)
Places (attended conferences) :
1)
National Institute of Standards and Technology (NIST)
2) University of
Colorado, Optoelectronic Computing System Center (UC-OCSC)
3) IEEE/LEOS The
3rd Summer Topical Meeting on Smart Pixels
In general, a smart pixel is a device used for optical interconnection and optical information processing with many pixels arranged on a two-dimensional array, composed of detectors, electronic circuits, and light emitting or light modulating elements. There may be no light emitting or light modulating elements. Some speaker commented that "Smart Pixel" will evolve to become "Intelligent Pixel."
There are five laboratories of NIST in Boulder, about an hour's drive from Denver, the capital of Colorado State, and I visited mainly the Optoelectronics Division of the Electronics and Electrical Engineering Laboratory. They seemed to be focusing on research on the standard, and in particular, on high-precision detector and measurement technology which allows measurement of light over a wide range of wavelengths and intensities. They seem to be loyal to their position as a standards institute, hence I did not see their pioneering work in new fields. I am not in a position to evaluate the entire NIST from just one visit to a small part of it, but it showed a typical example of the National Institute.
In the Optoelectronic Computing System Center of Colorado University, also in Boulder, I visited its laboratories and had a chance to discuss their research activities. UC-OCSC has accomplished many results in the optical computing field with many researchers, and plays a central role in the world. In recent years, they have been working on systems research, mainly on silicon-based Smart Pixels. In particular, they are concentrating on building an optical system to implement parallel optical interconnection based on spatial propagation by taking advantage of the spatial parallelism of light and the characteristics of Smart Pixels. Silicon circuits for Smart Pixels are supplied by Bell Laboratory and MOSIS.
I felt strongly, through discussion with some researchers there, the importance of the cooperation of many researchers and the management of them after the direction of the research has been defined to build a working system, even on a small scale. We also agreed on the need for close communication among research institutes to promote systems research.
The IEEE/LEOS Topical Meeting on Smart Pixels was held in Keystone, a ski resort three hour's drive from Denver. Its altitude at 3,000 m, drastic changes of temperature that may cause snowfall in summer, dry atmosphere, and low air pressure made some participants sick.
I gave a presentation entitled "Neuron Devices Based on Point Contact Phototransistors." I proposed a device which can be integrated in two dimensions composed of compound semiconductors with a brand new structure, and discussed its feasibility of integration. However, the main stream of the meeting was silicon IC-based Smart Pixel, and therefore the direction of fabricating circuits with compound semiconductors constituted only a minor group. I felt from this meeting that studies on the implementation of optical interconnection were centered around the Bell Laboratory. It was also clear that the development of a high-performance detector was a key to build larger-scale systems with more advanced functions as a future challenge.
In America, Smart Pixels are provided to universities by Bell Laboratory and MOSIS for which research is in progress. Without such assistance, it is difficult for individual universities and research institutes to conduct systems research. This partly accounted for the reason why Japan gave only few presentations. In a total of 52 presentations, only 4 were made by groups from Japan, and only 1 addressed for the application to a system. Since it is clear that future research on optical computing and optical interconnection will be focused on Smart Pixels, I think it is a major problem that in Japan only a part of NTT is engaged in such research.