Patent ID: 7705869

Claim:
A line head, comprising: a head substrate that includes a plurality of light emitting element groups as groups of light emitting elements; a lens array that includes a plurality of lenses each of which faces the corresponding light emitting element group in a first direction; and a light shielding member that is disposed between the head substrate and the lens array and includes a plurality of light shielding plates which are arranged side by side in the first direction while defining a space layer therebetween, wherein each of the plurality of light shielding plates is provided with a plurality of light guide holes penetrating in the first direction and facing the plurality of light emitting element groups in the first direction respectively, the plurality of light guide holes facing each of the light emitting element groups are arranged in the first direction respectively to form a plurality of light guide portions, lights from the plurality of light emitting element groups are incident on the plurality of lenses through the plurality of light guide portions respectively, a gap is defined between the head substrate and the light shielding plate closest to the head substrate in the first direction out of the plurality of light shielding plates, thicknesses of the gap and the space layers become smaller with distance from the head substrate, among the gap and the space layers, the space layer between the light shielding plate closest to the lens array and the light shielding plate second-closest to the lens array has the smallest thickness, and among the gap and the space layers, the gap has the largest thickness.