A quantity-of-light adjusting device comprises a first quantity-of-light adjusting
blade and a second quantity-of-light adjusting blade which move to adjust quantity
of light, and a detecting member which detects that the first quality-of-light
adjusting blade is at a predetermined location while also detecting that the second
quantity-of-light adjusting member has moved to the predetermined location following
the first quantity-of-light adjusting blade moving from the predetermined location,
so that the state of adjusting of the aperture with the quantity-of-light adjusting
means can be detected by a single detecting member.
