To provide a lens barrel having an optical filter at a low cost, a lens
barrel is provided and has: an aperture between two lenses held in the
lens barrel; and at least one optical filter disposed to rearward of one
of the two lenses, wherein the one of the two lenses is situated closer
to the camera body than the other of the two lenses, and the at least one
optical filter blocks or passes light depending on a wavelength of the
light.