Compact digital camera objective with interdigitated element alignment, stray light suppression, and anti-aliasing features

A lens system comprising:

• a housing having an opening, the housing including,
• (a) a first lens element including a first mechanical flange;
• (b) a second lens element including a second mechanical flange;
• (c) an opaque spacer that interdigitates with the first and second mechanical flanges of the first and second lens elements;
• (d) a third lens element including a third mechanical flange that interdigitates with the second mechanical flange of the second lens element;
• and
• (e) a fourth lens element including a fourth mechanical flange that interdigitates with the third mechanical flange of the third lens element.

A camera system having an optical axis, comprising:

• a lens system including,
• a first lens element on the optical axis, the first lens element including a diffractive surface disposed on one surface and made of crown-like material,
• an aperture stop,
• a second lens element on the optical axis, the second lens element made of a flint-like material,
• a third lens element on the optical axis, and made of crown-like material, and
• a fourth lens element on the optical axis, and made of crown-like material;
• and
• a detector array on the optical axis behind the first through fourth lens elements.