Table 1. Results of area measurement and error rate from the experimental model of color patch method (d: distance (cm), θ: angle (degree)).

	d: 30 θ: 90	d: 30 θ: 60	d: 30 θ: 30	d: 40 θ: 90	d: 40 θ: 60	d: 40 θ: 30	d: 50 θ: 90	d: 50 θ: 60	d: 50 θ: 30
measured area (cm2)	12.56	12.84	12.83	12.81	12.23	12.82	12.81	13.10	12.95
error rate (%)	-0.05	2.18	2.10	1.94	-2.68	2.02	1.94	-3.39	3.05