College Physics

axis of a polarizing filter:

Brewster’s angle:

Brewster’s law:

birefringent:

coherent:

confocal microscopes:

constructive interference for a diffraction grating:

constructive interference for a double slit:

contrast:

destructive interference for a double slit:

destructive interference for a single slit:

diffraction grating:

diffraction:

direction of polarization:

Huygens’s principle:

horizontally polarized:

incoherent:

interference microscopes:

optically active:

order:

Figure 27.54A confocal microscope provides three-dimensional images using pinholes and the extended depth of focus as described by wave optics. The right pinhole

illuminates a tiny region of the sample in the focal plane. In-focus light rays from this tiny region pass through the dichroic mirror and the second pinhole to a detector and a

computer. Out-of-focus light rays are blocked. The pinhole is scanned sideways to form an image of the entire focal plane. The pinhole can then be scanned up and down to

gather images from different focal planes. The result is a three-dimensional image of the specimen.

Glossary

the direction along which the filter passes the electric field of an EM wave

θb= tan−1

⎛

⎝

n 2

n 1

⎞

⎠,wheren^2 is the index of refraction of the medium from which the light is reflected andn^1 is the index of

refraction of the medium in which the reflected light travels

tanθb=

n 2

n 1 , wheren 1 is the medium in which the incident and reflected light travel andn 2 is the index of refraction of the

medium that forms the interface that reflects the light

crystals that split an unpolarized beam of light into two beams

waves are in phase or have a definite phase relationship

microscopes that use the extended focal region to obtain three-dimensional images rather than two-dimensional images

occurs when the condition d sinθ=mλ(form= 0, 1, –1, 2, –2, ...)is satisfied,

wheredis the distance between slits in the grating,λis the wavelength of light, andmis the order of the maximum

the path length difference must be an integral multiple of the wavelength

the difference in intensity between objects and the background on which they are observed

the path length difference must be a half-integral multiple of the wavelength

occurs when D sinθ=mλ,(form= 1, –1, 2, –2, 3, ...), whereDis the slit width,λis the

light’s wavelength,θis the angle relative to the original direction of the light, andmis the order of the minimum

a large number of evenly spaced parallel slits

the bending of a wave around the edges of an opening or an obstacle

the direction parallel to the electric field for EM waves

every point on a wavefront is a source of wavelets that spread out in the forward direction at the same speed as the wave

itself. The new wavefront is a line tangent to all of the wavelets

the oscillations are in a horizontal plane

waves have random phase relationships

microscopes that enhance contrast between objects and background by superimposing a reference beam of light

upon the light emerging from the sample

substances that rotate the plane of polarization of light passing through them

the integermused in the equations for constructive and destructive interference for a double slit

988 CHAPTER 27 | WAVE OPTICS

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