An Alvarez lens, comprising: a first lens having a first low-contrast metasurface; and a second lens; wherein the first lens and the second lens are arranged along an optical axis and configured such that displacement between the first lens and the second lens along a transverse axis in relation to the optical axis will produce a non-linear change in focus; wherein the first low-contrast metasurface has optical activity at a first wavelength and comprises: a plurality of cylindrical posts formed from a first material and arranged on a substrate in a square pattern, wherein the plurality of cylindrical post are formed from a material having a first refractive index of 2.1 or less; interstices between individual posts of the plurality of cylindrical post comprising an interstitial substance with a second refractive index that is 0.6 to 1.1 less than the first refractive index; wherein the individual posts of the plurality of cylindrical posts have a diameter in a range of 1/8 of the first wavelength to 2/3 of the first wavelength; wherein the plurality of cylindrical posts have a periodicity in a range of 0.4 times the first wavelength to 1.0 times the first wavelength; and wherein the plurality of cylindrical posts have a thickness in a range of 0.5 times the first wavelength to 1.0 times the first wavelength. a first lens having a first low-contrast metasurface; and a second lens; wherein the first lens and the second lens are arranged along an optical axis and configured such that displacement between the first lens and the second lens along a transverse axis in relation to the optical axis will produce a non-linear change in focus; wherein the first low-contrast metasurface has optical activity at a first wavelength and comprises: a plurality of cylindrical posts formed from a first material and arranged on a substrate in a square pattern, wherein the plurality of cylindrical post are formed from a material having a first refractive index of 2.1 or less; interstices between individual posts of the plurality of cylindrical post comprising an interstitial substance with a second refractive index that is 0.6 to 1.1 less than the first refractive index; wherein the individual posts of the plurality of cylindrical posts have a diameter in a range of 1/8 of the first wavelength to 2/3 of the first wavelength; wherein the plurality of cylindrical posts have a periodicity in a range of 0.4 times the first wavelength to 1.0 times the first wavelength; and wherein the plurality of cylindrical posts have a thickness in a range of 0.5 times the first wavelength to 1.0 times the first wavelength. a plurality of cylindrical posts formed from a first material and arranged on a substrate in a square pattern, wherein the plurality of cylindrical post are formed from a material having a first refractive index of 2.1 or less; interstices between individual posts of the plurality of cylindrical post comprising an interstitial substance with a second refractive index that is 0.6 to 1.1 less than the first refractive index; wherein the individual posts of the plurality of cylindrical posts have a diameter in a range of 1/8 of the first wavelength to 2/3 of the first wavelength; wherein the plurality of cylindrical posts have a periodicity in a range of 0.4 times the first wavelength to 1.0 times the first wavelength; and wherein the plurality of cylindrical posts have a thickness in a range of 0.5 times the first wavelength to 1.0 times the first wavelength. <EOS>