Optical and Reflective Characteristics Measurement and Focal Length Calculation of a Hollow Tetrahedral Corner and a Solid Highly Retroreflective Cubes

Table 2

The number of Newton ring and focal length for each case individually.

N	= = [m]	N	D[mm]	δ [μ]	R[m^2/str]	[m^−1]	f [m]
6.5	250	2.2	50	1.25	60.3	-0.01194	-83.75
5.5	312	2.0	50	1	135.19	-0.00557	-179.2
4	500	1.8	50	0.75	300.14	-0.00511	-195.6
3	625	1.5	50	0.5	600.55	-0.00410	-243.9
2	1250	1.14	50	0.25	2500.21	-0.00300	-300.0
1	2000	1.0	50	0.5	3200	-0.00203	-492.6
0.5	2500	0.5	50	0.125	5120	-0.00112	-892.8
0.3	4500	0.2	50	0.075	6212	-0.00081	-1234
0.196	5400	0.2	50	0.05	6852	-0.00051	-1960