first lens 10 is engaged with the second lens 20 a third included angle u03b8 equal to a difference between the first included angle u03b1 and the second included angle u03b2 is defined between the inner circumferential engagement surface 18 s and the outer circumferential engagement surface 28 s the following explains in detail how the error is overcome using the lens arrangement 100 the smallest diameter of the inner circumferential engagement surface 18 s is equal to or less than the largest diameter of the outer circumferential engagement surface 28 s to ensure the first lens 10 can engage with the second lens 20 the inner circumferential engagement surface 18 s defines a number of grooves 181 equidistantly arranged along a circumferential direction thereof a number of elastic elements 30 are fixed in the respective grooves 181 and each elastic element 30 can be flexibly deformed along a direction perpendicular to the bottom of the corresponding groove 181 in detail each of the elastic elements 30 includes a spring 31 and a shim 33 fixed on a distal end of the spring 31 in the present disclosure the spring 31 is adhered to the bottom of the corresponding groove 181 and the shim 33 is adhered to the spring 31 a free length of the spring 31 is longer than a distance between the inner circumferential engagement surface 18 s and the bottom of the corresponding groove 181 in order to avoid scratching the second lens 20 each of the elastic elements 30 is made either of a soft material a very flexible material or both furthermore an aperture stop 40 is disposed between the first engagement portion 18 and the second engagement portion 28.