Paraxial lens design of anamorphic lenses with a fixed anamorphic ratio

Abstract

If the stop lies on the right of the anamorphic lenses, the entrance pupils in the tangential plane and the sagittal plane might not coincide with each other. In this condition, the anamorphic ratio will change according to the position of the object, which is not preferred in filming and machine vision. In view of this, a systematic approach for the paraxial design of anamorphic lenses with common entrance pupils is provided. Two basic types of anamorphic attachment are presented: basic anamorphic attachment and basic anamorphic zoom attachment. The anamorphic ratio can be changed by changing the interval distances between lens components if anamorphic zoom attachments are adopted. Formulas defining the interval distances between lens elements, the object position, the stop position, and the anamorphic ratio are derived. Illustrating figures and examples are also provided for each lens type.