Physical Optics Flashcards
L
distance from slit to screen
d
slit spacing
Diffraction
bending of a wave due to a barrier or opening
What affects the bending?
size of opening/obstacle compared with wavelengths of the wave
Opening > wavelength
Waves move with little diffraction, creates a large shadow region
Opening similar to wavelength
very pronounced diffraction, wavefronts form a circular pattern with no shadow regions
The smaller the opening
the more significant the diffraction
Shadow region
regions with no wave activity
Huygen’s principle
- Every oscillator in a wave creates spherical wavelets that propagate outwards.
- The wavefront created by these oscillators is due to the combined interference of the wavelets
Constructive interference
identical wave crests is added together to create a single larger wave
Effects of constructive interference
- water waves increase in height
- sound becomes louder
- light becomes brighter
Destructive interference
When a wave crest meets a wave through, these waves will be canceled entirely
Effects of destructive interference
- absence of wave activity
- water becomes flat
- sound becomes quiet
- darkness instead of brightness
Monochromatic light
light composed of only one wavelength
When lines of constructive interference hit the screen
bright bands of light can be seen
