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Schottky diodes were fabricated using aluminum/neutralized-sulfonated-polyaniline (SPAN) junctions. I–V and C–V measurements were made, and the barrier height (ΦB) and the background concentration (NB) were determined to be 0.8 V and 4×1017/cm3, respectively. Using these diodes as gate control, depletion-mode thin-film transistors were fabricated with a source and drain made of gold Ohmic contacts. The transistors were characterized by I–V measurements, and the carrier mobility determined from devices operating in the |VG|>|VDS| “linear” regime was about 0.01 cm2/V s. This high value of mobility could be attributed to the spherulitic (partially ordered) structures observed in the SPAN thin films. Field-effect transistors were also fabricated on SPAN films deposited on an n-doped silicon substrate acting as the gate electrode with a thermally grown oxide layer. A reasonably high on/off ratio (∼4×103) was measured in these devices.

A new holographic implementation of a sampling technique permits, in principle, a straightforward representation of 2-D space-variant optical systems. The set of sample transfer functions required for the representation is recorded on a single holographic plate by utilizing phase coded reference beams. Because this approach does not depend on volume effects in the recording medium in an essential way, the holograms can be produced digitally, as well as optically. Basic concepts and preliminary experimental investigations related to this approach are presented and discussed.

A technique is described for recording representations of space-variant optical systems as volume holograms. The transfer-function holographic representations obtained are then placed in the Fourier plane of a coherent optical processor for playback. Due to the space-variant nature of the systems represented, the input plane of the system to be represented holographically is spatially sampled. As a result, the volume hologram medium actually contains a number of holograms that have been angle multiplexed to avoid interference problems. Limitations associated with the thickness of the recording medium are calculated for imaging systems, and experimental results are presented for one lens and two lens magnifiers.

Some principles that have guided the development of engineering courses in the past are identified and applied to the development of strategies for contemporary circumstances. Implications of current changes in constraints are explored for class meetings and for student work outside of class. The realization that two‐thirds of a typical university academic course, and most of the learning, occurs outside the class meeting times compels careful focus by faculty on the design of interactive learning experiences to help students learn proficiently outside the class room. Designing courses of study in which the learning activities outside, as well as inside, the class room form a coherent and effective whole can improve courses dramatically.