An interactive image processing system based on the minicomputer, INTERDATA 7/32, has been developed. This system is adaptable for developing a variety of image processing algorithms efficiently. Features of the system are that (1) it is composed by centering on the main memory of the minicomputer and no buffer memory is equipped, (2) it has hardwares for displaying coded and/or continuous-tone images efficiently, (3) it is equipped with a hardware to be able to execute two-dimensional convolution at high speed, and (4) data acquisition, data display and data processing can be made at high speed for a high resolution image. In order to transfer high resolution image data at high speed between the main memory and the developed hardwares or peripherals, direct memory access facilities are adopted together with time sharing technique. Applicability of the developed system is demonstrated through experiments for simple pattern analysis and for iterative image restoration for a linearly degraded image.

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The competition effect between the 0.63μm and 1.15μm lines in He-Ne laser is studied experimentally. The result is that the 1.15μm line is much influenced by the 0.63μm line but the 0.63μm line is little by the 1.15μm line.
The output coupling of simultaneously operated laser at 0.63μm and 1.15μm is obtained analytically from the above result. This experimental analysis agreed well with the measurement of the power coupled out of exit mirror. The powers of 3.3mW at 0.63μm and 0.5mW at 1.15μm were obtained under longitudinal multi-mode operations.

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The present experiments were intended to examine spatial interaction in the yisual system, by measuring detection threshold of a center grating in the presence of flanking gratings with various contrast and spatial frequency. Two kinds of phase relation between a center grating and flanking gratings were manipulated. The results showed that: (1) Under the condition of in-phase configuration, the sensitivity for a center grating has a upward peak as a function of the contrast of flanking gratings. (2) Whereas, under the condition of out-of-phase configuration, the sensitivity for a center grating decreases monotonically. (3) The effects of flanking gratings on the sensitivity of a center grating is specific to spatial frequency. These results were interpreted in terms of spatial summation in the spatial frequency tuning mechanism below threshold, and lateral inhibitory interaction between the mechanisms above threshold.

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Detectability of a center grating with flanking gratings was measured for different spatial frequency, separation and phase relation between a center grating and flanking gratings. For in-phase configuration, the detectability is facilitated, whereas, for out-of-phase configuration, the detectability is inhibited. The effect of flanking gratings decreases repeating facilitation and inhibition alternately, as separation between a center grating and flanking gratings increases. The spatial periods of facilitation and inhibition depend on the spatial frequency of a center grating. These characteristics, which are the same as predicted by Fourier transformation of the contrast sensitivity functions of spatial frequency channels, seem to reflect the space domain properties of spatial frequency channels.

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The contribution of luminance contrast of adapting gratings to the strength of the McCollough effect was examined. Using color-cancellation matching technique, the strength was measured as a function of luminance contrast of adapting gratings. Chromatic combinations of adjacent stripes (chromatic bars interspersed with achromatic or complementary chromatic bars) and spatial frequencies of adapting gratings were changed.
The ratio of the measured strength under various luminance contrast conditions to the strength under 1.0 luminance contrast condition showed a similar slope as a function of luminance contrast, regardless of the differences in chromatic combinations and spatial frequencies. It was concluded that the strength of the McCollough effect is linked closely with luminance contrast of adapting gratings and the information of luminance contrast is detected in the induction of the McCollough effect, even if the edges of stripes of adapting gratings are formed with complementary colors.

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