An optical detector device for a counter, comprising a consumption indicator, formed from a rotating disc (4) with a section called active (4A) and optical elements of the receiver and emitter types opposite the disc. The received signal from which is used to infer the number of rotations of the disc and which comprises at least two of the optical elements (6A, 6B) of one type and at least one of the optical elements (7) of the other type. The section (4A) is a reflecting section with a center angle of 45 to 225 DEG and the two optical elements of one type (6A, 6B) are emitting elements, emitting a beam of light, where the lines connecting each trace (S(6A), S(6B)) of the beams on the disc (4) to the center of the disc form an angle at the center which is not zero.