The document discusses various aspects of sight and vision. It begins by labeling the parts of the eye and describing their functions, including the aqueous humour, vitreous humour, optic nerve, fovea, retina, lens, pupil, cornea, and iris. It then explains how the ciliary muscles shape the lens to focus light for near and far vision. The document also discusses depth of vision, rods and cones in the retina, photopic and scotopic vision, color blindness, additive and subtractive color mixing, and how lighting can affect color perception.

1. presents
a production
Sight and Wave
Phenomena
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2. Inside the eye
Learn the labellingVitreous humour
of the eye Aqueous humour
Optic nerve
Fovea
Retina
Blind spot
Lens
Pupil
Cornea
Iris
2 Ciliary muscle

3. Inside the eye
Learn the functions of the eye parts
Aqueous humour Retina Fovea
Lens Optic nerve
Pupil
Cornea
Iris
Blind spot
Ciliary muscle Vitreous humour
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4. Accommodation
How the ciliary muscles shape the lens to focus light
Near point The closest
distance that an eye can
focus. Conventionally, this is
25 cm.
Far point The furthest
distance that an eye can
focus (ciliary muscles
relaxed). Conventionally,
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this is at infinity.

5. Depth of vision
Depth of vision refers to
the ability to see things in
three dimensions and thus
to judge distance.
The different cues
we use to see 3D
are:
Relative sizes of objects;
perspective; parallax; binocular
vision (using two eyes)
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6. Rods and cones
Two types of receptor cell in the retina
Cones: detect colour and
visual acuity (sharpness).
There are three types of
cone which are sensitive
to different wavelengths
of light.
Red (long λ, 560 nm)
Rods: detect movement and low
Green (medium, 530 nm)
light intensity. Very sensitive to
Blue (short, 430 nm)
light but not colour.
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7. Retina
The graph shows that cones
are concentrated at the fovea
where there are no rods. The
rods are spread more evenly.
Photopic vision = Scotopic vision = no
colour under normal colour, dim light ie the
lighting ie the cones 7
rods

8. Colour blindness
The commonest form is red-green, which
is caused by problems in the cones. It is
genetically inerited, usually by males.
The Ishihara test is
used to identify colour-
blindness. This is a
simulation of how
people see the top left
image. Deuteranomaly
is the most common
due to a mutation in
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the green pigment.

9. RedGreenBlue
The continuous spectrum of visible light can be
reduced for sense perception purposes to three
Primary colours: Red, Green and Blue (R, B, G).
Red light contains only R and no B or G
Red objects reflect only R and absorb B and G
Red filters transmit only R and absorb B and G
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10. Colour mixing
Additive mixing eg Primary Colours:
light bulbs Cyan, Magenta,Yellow
Primary Colours: Secondary Colours:
Red, Blue, Green Red, Blue, Green
Secondary Colours: Subtractive mixing
Cyan, Magenta,Yellow eg filters

11. Perception
Lighting effects can affect the way we see things.
Shadow = solidity
Blue = cold The warmer tones are
nearer to the red end
Orange = warm of the visible spectrum.
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12. Image of mouse retina: Thomas Deerinck
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