Abstract
An experiment of anisotropy on perception of length in peripheral vision was carried out for the purpose of further investigation with the results of the author's previous experiment (2nd report). It was suggested, in the 2nd report, that either some charactor of constancy in problem of parallelness is in existence or anisotropy of⊿coordinate system itself is in existence, from the experimental fact of subjectively adjusted parallel lines were not expressed geometricaly parallel but concaved against point of fixation in⊿coordinate system. Accordingly, requiring experimentally PSE of perceived length with the direction of the upper, lower, right and the left side against the point of fixation in peripheral vision, and then set up the regression equation between the PSE of the two arbitrary direction. On the bases of the equation, the well known visual anisotropy phenomena were investigated. Continuously interposing the⊿_0 transformation, the coefficient of principal directional anisotropy were required, and under some assumption with the anisotropy for arbitrary direction, an anisotropic cooridnate system for perspective vision was construted, which represents the subjective localization against objective stimulus. The author named the anisotropic coordinate system as⊿_1 coordinate system, and consider the meaning of it, further, reexamined the result of experiment II with it.
