Patent ID: 7564474

Claim:
A line head module comprising: a line head in which a plurality of organic EL elements is arranged; a lens array made by arranging lens elements which focus light from the line head; and a head case supporting the line head and the lens array, the head case including a side wall with an inner peripheral surface, the inner peripheral surface being formed with a stepped seat along the entire periphery thereof and a slit-shaped opening portion at a lower end portion thereof, the line head being provided with an element substrate, a first electrode formed on the element substrate, a second electrode formed so as to face the first electrode, a functional layer formed between the first and second electrodes and including at least a light-emitting layer, and a seal substrate attached to the element substrate via an adhesive arranged on the second electrode, the lens array being arranged in the slit-shaped opening portion of the head case, a first seal member being arranged in a corner between the lens array and the entire inner periphery of the lower end portion of the head case so as to airtightly join the lens array to the head case, the line head being arranged on the stepped seat of the head case, a second seal member being arranged in a space between the entire inner periphery surface of the head case and an entire outer periphery of the side surface of the line head, so as to airtightly join the line head to the head case, and to form an airtight seal in a first chamber formed between the line head and the lens array, and the second seal member covering the entire peripheral side surface of the seal substrate, the adhesive, and the element substrate, and covering a part of the upper surface of the seal substrate.