A light adjusting apparatus for use with a small-size image pickup equipment. The light adjusting apparatus includes two substrates, out of which, one has an aperture, a spacing portion which regulates a distance between the two substrates, at least one incident-light adjusting unit which has a shaft member which becomes a center of rotation, and which is turned in a plane perpendicular to an optical axial direction, between the substrates, and at least one driving unit which drives the incident-light adjusting unit. Incident light which passes through the aperture is adjusted by turning the incident-light adjusting unit alternately, to the aperture and to a retracted position which is retracted from the aperture, by the driving unit. The light adjusting apparatus includes a notch which receives the shaft member, formed in the substrate, and a retaining portion which prevents the incident-light adjusting unit from dropping.