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Why are the axons of ganglion cells part of the optic nerve?

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details of the mammalian eye — Photoreception The mammalian eye has a cornea and a lens and functions as a dioptric system, in which light rays are refracted to focus on the retina.

In the biology of photoreception, the retina functions as a complex nervous structure that converts light into chemical and electrical signals. These signals are processed through layers of neurons, including bipolar cells, before reaching the innermost layer of ganglion cells.12

The axons of these ganglion cells are part of the optic nerve because they serve as the primary output pathway for visual information. After the retina processes visual stimuli, the resulting messages are transmitted to the ganglion cells, which then send these impulses out of the eye along their axons. These axons converge at the optic disk to form the optic nerve, which acts as a central tract connecting the retina to visual relay stations in the brain, such as the lateral geniculate body.134