US 11,835,879 B2
Exposure head and image forming apparatus
Yusuke Kamata, Tokyo (JP)
Assigned to CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed by CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed on Feb. 17, 2022, as Appl. No. 17/674,114.
Application 17/674,114 is a continuation of application No. PCT/JP2020/031195, filed on Aug. 19, 2020.
Claims priority of application No. 2019-152947 (JP), filed on Aug. 23, 2019.
Prior Publication US 2022/0171307 A1, Jun. 2, 2022
Int. Cl. G03G 15/04 (2006.01); H01L 25/075 (2006.01); H01L 33/62 (2010.01)
CPC G03G 15/04036 (2013.01) [G03G 15/04063 (2013.01); H01L 25/0753 (2013.01); G03G 15/04054 (2013.01); H01L 33/62 (2013.01)] 11 Claims
OG exemplary drawing
 
1. An exposure head, comprising:
a printed-circuit board;
a plurality of light emitting element array chips; and
an adhesive for fixing the plurality of light emitting element array chips to the printed-circuit board,
wherein each of the plurality of light emitting element array chips includes a plurality of light emitting portions and a wire bonding pad,
wherein the plurality of light emitting element array chips are arranged in a staggered manner in a longitudinal direction of the printed-circuit board,
wherein one end portion of a first light emitting element array chip among the plurality of light emitting element array chips overlaps one end portion of a second light emitting element array chip adjacent to the first light emitting element array chip when viewed in a width direction orthogonal to the longitudinal direction, and another end portion of the second light emitting element array chip overlaps one end portion of a third light emitting element array chip adjacent to the second light emitting element array chip when viewed in the width direction,
wherein the adhesive for fixing the second light emitting element array chip to the printed-circuit board is applied in an area between the one end portion of the first light emitting element array chip and the one end portion of the third light emitting element array chip,
wherein the first light emitting element array chip and the second light emitting element array chip are arranged with a gap of a first length in the width direction,
wherein, in the width direction, the adhesive for fixing the second light emitting element array chip protrudes, by a second length longer than the first length, out of the second light emitting element array chip beyond an edge of the second light emitting element array chip, and
wherein a protrusion part of the adhesive for fixing the second light emitting element array chip is provided away from the first light emitting element array chip.