平面図形の立体視に関する研究 (I)

Y構造及びT構造

抄録

It seems to the present writer that bi-dimensional figures seen as solid have the forms Y and ↑, generally, and those which appear as plane have the forms T, + and×. Now he has designed 44 new figures of three types ; the first type contains the structural factors Y and ↑, the second type has the structural factors T, + and × and the third type contains both of these structural factors. These figures, drawn on 7 pictorial papers, were shown to the subject, who was asked to report whether he saw the figures as solid or plane after observing for a moment.
The subjects were 20 children of elementary school, 10 children of kindergarten and 14 university students. The results of the experiment were as follows : 87% of Ss saw the figures of the first type as solid and 89% of them observed the figures of the second type as plane (See Table 2). There were no essential differences among the children of elementary school and kindergarten, and the university students in these results. Thus we may conclude that each of the structural factors has its own power for making the figures appear eirher as three- or two-dimensional.
Koffka, Kopfermann and Metzger have explained the depth perception of two-dimensional drawings by the law of Gestalt, i. e. the organization theory. However, one may explain this phenomenon by the structural factors of the figures, Y, ↑ and T, +, × as described above. All usual ambiguous figures and the greater part of the figures which Koffka and others have used in their experimental studies, may be interpreted simply in this way. Moreover, according to the above point of view one can clearly understand such a tendency of a figure to appear as three-dimensional in spite of its regular and good shape, the tendency that was pointed out by Wood-worth.
Wallach and others have refered to the strong solid character of the form Y. They have ascribed its source to memory and experience. However, the author can not agree with this empiricistic explanation, because there are some perspective figures which reverse a familiar solid appearance, as in the case of the street figure with vertical parallels used in this study. After all, it would be true that the structural factors have the independent force, apart from the empirical factors, to make a drawing appear in three- or two-dimensions. The above explanation is not complete as Yet, because there are a number of figures which contain no structural factors of the type Y and the like, and yet appear as three-dimensional.
The author intends to study these figures farther in order to get the complete understanding of the depth perception of two-dimensional drawings.