The first order diffraction efficiency n1 of a Moiré lens depends on the chosen twisting angle θ, resulting in the corresponding optical power:

n1 = (sinc (θ2))2 (1)

The total efficiency is a product of the diffraction efficiency and the transmission efficiency  nt, which is approximately 96%. For a twisting angle of 45º, the diffraction efficiency is around 65%, therefore the total efficiency is approximately 62%.