Patent ID: 7583452

Claim:
A barrel for automatically aligning respective axes of a plurality of lenses, comprising: a main body configured for receiving the plurality of lenses therein, the main body having a main body axis; and a pair of protruding ribs formed on an internal surface of the main body, each protruding rib extending along the internal surface of the main body and parallel to the main body axis, each protruding rib thereby being configured for supporting the plurality of lenses thereon and for automatically aligning respective the optical axes of the plurality of lenses, wherein a first imaginary line is formed by perpendicularly connecting one of the protruding ribs and the main body axis of the barrel, a second imaginary line is formed by linearly connecting the other protruding rib and the main body axis of the barrel, and an included angle between the first imaginary line and the second imaginary line is about between 60 degrees and 150 degrees.