Additional list of symbols and definitions pertaining to the second biophysical function
| Symbol | Definition |
| Φa, Φaz | Absorbed flux in one layer at the base and at depth z |
| Jn | Surface density of pigment (molecules μm−2); Jn = n/At |
| δ | In situ path length in visual cells corresponding to a single pigment-laden lipid bilayer (lamella); δ = 15 nm is taken as its equivalent thickness |
| At | Total lamellar surface area of an outer segment |
| c | Concentration of visual pigment; c = n/Atδ = Jn/δ |
| n | Total number of visual pigment molecules contained in an outer segment |
| no, nz | Number of visual pigment molecules in a lamella at the base and at z |
| pz | Probability of absorption of a quantum by a single layer at z |
| γ | Quantum efficiency of bleaching; number of photons absorbed per number of photoactivations that result in bleaching |
| Sz | Signal from light activation (ionic current) at level z |
| Nz | Noise produced in the dark at level z (ionic current) |
| Symbol | Definition |
| Φa, Φaz | Absorbed flux in one layer at the base and at depth z |
| Jn | Surface density of pigment (molecules μm−2); Jn = n/At |
| δ | In situ path length in visual cells corresponding to a single pigment-laden lipid bilayer (lamella); δ = 15 nm is taken as its equivalent thickness |
| At | Total lamellar surface area of an outer segment |
| c | Concentration of visual pigment; c = n/Atδ = Jn/δ |
| n | Total number of visual pigment molecules contained in an outer segment |
| no, nz | Number of visual pigment molecules in a lamella at the base and at z |
| pz | Probability of absorption of a quantum by a single layer at z |
| γ | Quantum efficiency of bleaching; number of photons absorbed per number of photoactivations that result in bleaching |
| Sz | Signal from light activation (ionic current) at level z |
| Nz | Noise produced in the dark at level z (ionic current) |