Patent ID: 8169624

Claim:
A transmissive dimension measuring device comprising: a projector which projects light; and an optical receiver which is arranged with a predetermined interval to the projector, and receives light from the projector, the transmissive dimension measuring device measuring dimensions of an object to be measured passing between the projector and the optical receiver based on a change in amount of received light received by the optical receiver, the projector including: a substantially rectangular solid shaped projector housing provided therein with a light emitting element which emits light and a light projecting lens which converts light emitted by the light emitting element to parallel light; and a light projecting slit which has a shape with a predetermined width in a dimension measuring direction as a direction substantially horizontal to a bottom surface of the projector housing, from which the parallel light is emitted, the optical receiver including: a substantially rectangular solid shaped optical receiver housing provided therein with a light receiving element which receives light; and a light receiving slit which has a shape with a predetermined width in a dimension measuring direction as a direction substantially horizontal to a bottom surface of the optical receiver housing, on which the parallel light is incident, the transmissive dimension measuring device comprising: an incident light position display unit which is arranged on at least one side of the projector and the optical receiver in the dimension measuring direction, includes a plurality of indicating lamps each displaying a light receiving state in each area that divides a predetermined width in the dimension measuring direction of the light receiving slit, and displays a position on which the parallel light is incident to the optical receiver.