HUMAN VISION

The Eye

Light

WAVE

PARTICLE

Physics of the Eye’s lens

Parallax Lab

• Although each eye alone gives focus, together, they provide you with depth perception.

How?

Parallax

Light

WAVE

PARTICLE

Rods and Cones

Color Spectrum and Photopsin

Cone type Name Range Peak wavelength[1][2]

S (OPN1SW) - "tritan", "cyanolabe" β 400–500 nm 420–440 nm

M (OPN1MW) - "deutan", "chlorolabe" γ 450–630 nm 534–545 nm

L (OPN1LW) - "protan", "erythrolabe" ρ 500–700 nm 564–580 nm

Different opsins differ in a few amino acids and absorb light at different wavelengths as retinal-bound pigments.

Primary Colors Lab

The definition of a “primary color” is that no combination of other colors can be used to make it.

Why is this a bad definition?Given markers and top materials,

experimentally verify all types of primary colors and explain how your results reflect the known properties of photopsin.

Primary Colors of Light and Pigment

Colorblindness

Normal protanopia deuteranopia tritanopia

All three cone types Absence of red receptor

Absence of green receptor

Absence of blue receptor

Humans vs. Animals

Honeybees, bumblebees, and many butterflies

Illusions Lab (Discussion)• Why do you think we

experience the following as optical illusions?

optical illusions

• http://www.michaelbach.de/ot/• http://www.michaelbach.de/ot/ang_fraser/in

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