Fig. 5.

Sample images from on-axis resolution testing. The left most image is a digital camera image of the 1951 USAF test target used. The following three images from left to right are images of the test target acquired using the endoscope at working distances of 3, 5, and 10 mm. Minimum resolvable features were determined to be group 3 element 1, group 2 element 3, and group 1 element 5, respectively.