Lecture 3: Visual Processes

Question 1

Luminance

Answer 1

amount of visible light emitted from a surface/source

Question 2

Illuminance

Answer 2

amount of light incident occurring on a surface

Question 3

Reflectance

Answer 3

proportion of incident light that is reflected from a surface

Question 4

2 properties of Cornea

Answer 4

1) transparent window

2) gathers and concentrates light

Question 5

Objective of lens and cornea

Answer 5

to focus the image of the outside world on the retina in the back of the eye

Question 6

3 properties of the retina

Answer 6

1) light sensitive tissue
2) light triggers chemical and electrical events which are converted into neural information
3) transmits neural impulses to various areas of the visual cortex via the optic nerve

Question 7

2 Types of photoreceptors

Answer 7

1) rods

2) cones

Question 8

4 properties of rods

Answer 8

1) black and white vision
2) respond well to dim light
3) increased light = increased responsiveness, but they reach their maximum when light is dim
4) useless in full daylight

Question 9

3 properties of cones

Answer 9

1) colour vision
2) not so sensitive to light
3) used for daylight

Question 10

Photoreceptors in fovea

Answer 10

cones heavily focused in fovea, rods are absent

Question 11

Transduction

Answer 11

when the retina absorbs photon and turns light into nerve impulses