Budget Amount *help |
¥3,700,000 (Direct Cost: ¥3,700,000)
Fiscal Year 1996: ¥1,500,000 (Direct Cost: ¥1,500,000)
Fiscal Year 1995: ¥2,200,000 (Direct Cost: ¥2,200,000)
|
Research Abstract |
A new method to study the color vision is presented. The critical areas for spatial integration at threshold were obtained for lights of various wavelengths, presented against the achromatic or four chromatic background fields of the same retinal illuminance. The test and background fields were provided by a graphic display and a two-channel Maxwellian-view optical system. All apparatus were controlled by a microcomputer. The subjects' responses were obtained using the four buttons connected to the microcomputer. The critical area was defined by a procedure which fitted three lines to the data. The transition from the area of complete to partial spatial integration is defined by the critical area (xc) at which two straight lines with slopes of 0 and 0.5 intersect in a logI・A vs logA plot (where I=threshold intensity, A=test area), and the transition from the areas of partial spatial integration to complete absence of spatial integration is defined by the critical area (xp) at which two straight lines with slopes of 0.5 and 1 intersect respectively. Now, total integration (A) can be defined by thefollowing equation ; A_i=xc+xp-xc. On the 3 log Td white background, A_i was short for the lights of middle wavelengths, longer for the lights at the ends of the spectrum. However, there were some inter-subject differences. A_i also depended on the background wavelength. Generally, A_i obtained for the chromatic background was reduced with test lights of similar color, but is expanded with test lights of color opponent to the background, as compared with A_i obtained for the achromatic background of the same retinal illuminance. It was suggested that the integration area at threshold closely depended on the level of chromatic adaptation, as well as luminance adaptation.
|