ipRGCs (melanopsin)

Category

Vision

Function

Pupil, circadian photoentrainment

Quantity

~20,000–40,000

Density

Very sparse across the retina

Distribution

Scattered throughout both retinas; not for high-acuity sight

Relative Deployment

Notes

Intrinsically photosensitive retinal ganglion cells. Melanopsin peak ~480 nm. Also receive rod/cone input.

Interacting Systems & Components

• Photoreceptor (broader category)
• OPN4 (melanopsin) (photopigment gene)
• Nervous System (circadian signaling)