1988 Volume 30 Issue 5 Pages 936-941_1
We developed RESOLUTION TEST CHART of the image evaluation for electronic endoscopes. The specification of this chart is shown in Figure 1. The degree of resolution was expressed as the ability of line separation, namely, the number of lines/mm. For example, the resolution of 1 line/mm, means discrimination for 0.5 mm width black line with 0.5 mm width white line on its both side (reflection rate, black :2.0%, white :83.0%). The resolution of electronic endoscopes were not superior to that of optical fiber scope with this RESOLUTION TEST CHART (Figure 4). In comparison of the resolution among three new electronic endoscopes, TGI-50 D (Toshiba-Machida) was superior to GIF-V10 (Olympus) and VE-81205 (Welch-Allyn) (Figure 3). There was no difference in the ability of line separation between optical fiber scope and electronic endoscopes. However, the image with electronic endoscopes is more distinct than with optical fiberscope (Figure 5). Because of this characteristic point, we feel the electronic endoscopes show better resolution than that of optical fiber scope.
