Lens alignment apparatus

1. A lens alignment apparatus comprising:

a main lens holding frame having a main lens secured thereto;

an adjusting lens holding frame to which an adjusting lens to be aligned with the main lens is secured;

at least one radial groove formed in one of adjacent end surfaces of the main lens holding frame and the adjusting lens holding frame;

a centering hole, corresponding to said radial groove, formed in the other of said adjacent end surfaces of the main lens holding frame and the adjusting lens holding frame; and

an alignment member including a centering pillar portion inserted in said centering hole and an aligning portion engaged in said radial groove, said aligning portion being provided with a plurality of pairs of parallel alignment surfaces having an identical width and different distances from the axis of the centering pillar portion.

2. The lens alignment apparatus according to claim 1 , comprising a pair of said radial grooves provided at angular intervals of 90 degrees.

3. The lens alignment apparatus according to claim 1 , wherein the centering hole of the main lens holding frame and the centering pillar portion of the alignment member have interengageable polygonal shapes.