Optical Tests on a Curve Fresnel Lens as Secondary Optics for Solar Troughs

Table 4

Mean values of the concentration factor C.

Lens	mm	mm	mm	mm	mm
Lens_A	1.44	1.54	1.62	1.70	1.73
Lens_B	2.00	2.09	2.13	2.12	2.10
Lens_C	1.95	2.04	2.08	2.09	2.04