Abstract
A luminous marker or a reflection marker is used in motion capture and the two or three-dimensional image measurement as a target. When a luminescent marker is composed with LED, it is made with several LEDs because a luminous point of the LED is small. In this research, the influence of the size of the LED marker and the state of the lens focus on the measurement precision was investigated. It was found that the displacement of the luminescent marker could be measured by the resolving power of the subpixel even if in condition of some unfocused state.
