Share Email Print

Proceedings Paper

What do you see in a digital color dot picture such as the Ishihara pseudo-isochromatic plates? Web Accessibility Palette (WAP)
Author(s): Yasuyo G. Ichihara
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Internet imaging is used as interactive visual communication. It is different form other electronic imaging fields because the imaging is transported from one client to many others. If you and I each had different color vision, we may see Internet Imaging differently. So what do you see in a digital color dot picture such as the Ishihara pseudoisochromatic plates? The ishihara pseudoisochromatic test is the most widely used screening test for red-green color deficiency. The full verison contains 38 plates. Plates 18-21 are hidden digit designs. For example, plate 20 has 45 hidden digit designs that cannot be seen by normal trichromats but can be distinguished by most color deficient observers. In this study, we present a new digital color pallette. This is the web accessibility palette where the same information on Internet imaging can be seen correctly by any color vision person. For this study, we have measured the Ishihara pseudoisochromatic test. We used the new Minolta 2D- colorimeter system, CL1040i that can define all pixels in a 4cm x 4cm square to take measurements. From the results, color groups of 8 to 10 colors in the Ishihara plates can be seen on isochromatic lines of CIE-xy color spaces. On each plate, the form of a number is composed of 4 colors and the background colors are composed of the remaining 5 colors. Normal trichromats, it is difficult to find the difference between the 4 color group which makes up the form of the number and the 5 color group of the background colors. We also found that for normal trichromats, colors like orange and red that are highly salient are included in the warm color group and are distinguished form the cool color group of blue, green and gray. Form the results of our analysis of the Ishihara pseudoisochromatic test we suggest the web accessibility palette consists of 4 colors.

Paper Details

Date Published: 27 December 2000
PDF: 8 pages
Proc. SPIE 4311, Internet Imaging II, (27 December 2000); doi: 10.1117/12.411916
Show Author Affiliations
Yasuyo G. Ichihara, Hosen Gakuen College (Japan)

Published in SPIE Proceedings Vol. 4311:
Internet Imaging II
Giordano B. Beretta; Raimondo Schettini, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?