The structure effect on the secondary spectrum of long focal refractive optical system

The secondary spectrum is an important factor which constrain the improvement of image quality in long focal refractive optical system.Under the condition of using common glass,the quantity of the secondary spectrum varies as the structure form varies from one to another.In this paper,the secondary spectrum of several typical structure form is analyzed and compared.At last,some practical optical design examples are given to support the conclusion of comparison result mentioned above.