A camera frame assembly has an extendable lens module having a lens base, a traveler,
a front lens element, and a barrel cap. The lens base defines an optical axis.
The traveler moves along the optical axis between first and second positions, relative
to the lens base. The traveler has a front lens seat. A front lens element is disposed
in the front lens seat. A barrel cap is snapped on the traveler. The barrel cap
retains the front lens element in the traveler in alignment with the optical axis.
The barrel cap can be snapped off for replacement by a new or renewed barrel cap.
When the barrel cap is off, the front lens element is released and can be replaced
or can be held in place for reuse.
