Image exposure head and image forming apparatus

An exposure head comprising:

• a plurality of light-emitting devices configured to expose a rotationally driven photosensitive member with light, wherein each of the plurality of light-emitting devices includes:
• a first substrate,
• a first electrode layer including a plurality of electrodes that are (i) two-dimensionally arranged in a rotational direction of the photosensitive member and in the a direction of a rotational axis of the photosensitive member, and which (ii) are separately formed on the first substrate,
• a light-emitting layer laminated on the first electrode layer and configured to emit light when a voltage is applied,
• a light-emitting region including a second electrode layer capable of transmitting light, the light-emitting region being provided on a side of the light-emitting layer that is opposite to a side on which the first substrate and the first electrode layer are provided, the light-emitting region corresponding to the plurality of electrodes of the first electrode layer;
• and
• a second substrate on which the first substrates of the plurality of light-emitting devices are arranged at positions different from each other in an intersecting direction intersecting the rotational direction of the photosensitive member, with odd-numbered first substrates and even-numbered first substrates being at different positions in the rotational direction of the photosensitive member, and with the first substrates of the plurality of light-emitting devices being arranged so as to have overlapping portions in which respective end portions of the first substrates adjacent to each other overlap each other in the intersecting direction,
• wherein a driving portion including a converting portion is provided on each of the first substrates together with the light-emitting region, the converting portion being configured to convert received image data into the image data corresponding to a resolution.