(1) The Visual System & Light

Question 1

the branch of physics that relates to the properties of light and the function of vision; it involves a study of the human visual system and how it interacts with light

Answer 1

optics

Question 2

the inability to distinguish colors

Answer 2

color blindness

Question 3

energy radiated in the form of a wave caused by an electric field interacting with a magnetic field

Answer 3

electromagnetic radiation

Question 4

measured as the distance from one peak of one wave to the next wave

Answer 4

wavelength (λ)

Question 5

the number of wave cycles per second; it is expressed in units of hertz (Hz)

Answer 5

frequency

Question 6

part of electromagnetic radiation spectrum capable of exciting the retina and ultimately producing a visual sensation; it is the wavelengths of electromagnetic radiation to which the human eye is sensitive

Answer 6

visible light

Question 7

the amount of light incident on (striking) a surface

Answer 7

illuminance

Question 8

the amount of light leaving an object

Answer 8

luminance

Question 9

the ratio of reflected light versus the light striking the surface (illuminance)

Answer 9

reflectance (ρ)

Question 10

the ratio of light transmitted through the body versus the light illuminating the surface

Answer 10

transmittance (т)

Question 11

the ratio of the light absorbed versus the light striking the surface

Answer 11

absorptance (α)