What are the major challenges in Fresnel lens design and fabrication?

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Chao Shen

maybe how to improve the diffraction effiency. Fresnel lens' poor collecting effiency of light limits its applications. that is why the optical sieve so inspiring。 personal idea

Morteza A. Sharif

Anti reflection coating, I think is a solution to obviate Fresnel reflection effect which prevents the light to be collected.

Baohua Jia

Is there any high efficiency design idea? How about increase the numerical aperture?

Does anyone know how to calculate the focus resolution of a Fresnel lens?

Azmi Kadkly

People use the same Abbe formula to calculate the resolution of Fresnel lenses.

Do you mean using an effective numerical aperture to calculate the resolution?