GRADIENT-INDEX LENS WITH APLANATIC AND TELESCOPIC PROPERTIES Russian patent published in 2014 - IPC G02B3/02 

FIELD: physics.

SUBSTANCE: gradient-index lens is bounded by a first and a second refracting surface and is made of material with radial distribution of the refraction index n(y), defined by the equation $$n(y)=n_0\sec hay=\frac{2n_0}{e^{ay}+e^{-ay}},$$ where n₀ is the refraction index on the axis and a is a constant. Lens thickness d on the optical axis z is a multiple of double the nominal focal distance F, equal to $$F=\frac{\pi }{a}.$$ The lens has equal front sF and back s'F' sections. For thickness which is a multiple of F, the projection of the lens thickness on the optical axis in any plane containing the optical axis for any two points on the first and second surfaces, having the same absolute value of height relative to the optical axis, but lying on different sides of the optical axis, is equal to F. For lens thickness which is a multiple of 2F, the projection of the lens thickness on the optical axis in any plane containing the optical axis for any two points on the first and second surfaces, having the same absolute value of height relative to the optical axis and lying on the same side of the optical axis, is equal to 2F.

EFFECT: enabling selection of different forms of refracting surfaces, simple lens design, providing aplanatic and telescopic properties at the same time.

5 cl, 65 dwg, 128 tbl