A compound lens made of two or more lenses of different materials. The materials are chosen such that the effect of chromatic aberration is cancelled in the compound lens.
The physical opening of an optical system. When there is no actual border blocking the light entering the system, the lens boundary is the aperture.
Aberration of a polychromatic image due to different wavelengths following different optical paths. This is due to the dispersion of the refractive indices of the optical components in the system.
A mathematical function that has a value of zero everywhere except a distinct, well-defined point.
Destructive Interference
Interference pattern where the resultant irradiance is smaller than any of the components.
A principle proposed by Fermat that light travels along the path of shortest time.
A transformation of a function from a space domain into a frequency domain. Exposes the underlying frequencies of the signal. Very useful for signal processing, as the mathematics of signals become less complicated in the frequency space.
The expansion of a periodic function as an infinite series of sinusoidal terms.
The diffraction that occurs when the distance between the light source and aperture as well as the distance between the aperture and the screen are both very large compared to the size of the aperture. Because the light source is so far away one can approximate its origin to be at infinity in which case the light rays coming from the source would be parallel and the wavefronts would be planar as opposed to spherical.
Every point on a propagating wavefront serves as the source of spherical secondary wavelets, such that the wavefront at some later time is the envelope of these wavelets
In phase
When the maximums and minimums of a wave coincide
A material property that describes the interaction of propagating light with the medium it travels through.
The amount of light that reaches the screen. This is a measure of irradiance which is the time average of the resultant electric field squared. This depends on whether the two waves (and thus their electric fields) interfere constructively or destructively at the screen.
Lateral chromatic aberration
Major axis (ellipse)
Marginal ray
Meridional plane
Minor axis (ellipse)
Monochromatic
Off-axis
Optical axis
Optical sine theorem (Abbe sine condition)
Out of phase
When the maximums and minimums of a wave do not coincide
Paraxial approximation
Paraxial focus
Paraxial region
Particle-wave dualityA model for
matter and energy propagation that states that any moving particle can be
represented by a propagating matter-wave
and any wave can be represented by a particle localized in space.
Petzval condition
Petzval surface
Phase velocity
Velocity at which the transmitted wave moves, (not the velocity of the individual
photons)
Plasma
The fourth state of matter. Plasma is a highly ionized gas; the high
temperatures have stripped the atoms of the electrons.
Principle plane
Primary aberrations
Primary image
Primary monochromatic aberration (Seidel aberration)
Quasimonochromatic light
Ray tracing equation
Refracted
Relative permeability
Relative phase shift
The phase difference between adjacent secondary wavelets of a light source
The first set of deviations of a ray from the ideal paraxial propagation through a refracting surface. Also called primary monochromatic or third-order aberrations.
Unobstructed waves propagate in straight lines perpendicular to the wavefronts.
Totally constructive interferenceA type of constructive interference where the resulting irradiance is a linear sum of the component irradiances.
Totally destructive interferenceInterference pattern with a net irradiance of zero
Wavefront A surface joining all points of equal phase of a wave. Wavefronts are always perpendicular to the propagation rays of the wave.
Young's Double Slit ExperimentAn experimental setup where coherent monochromatic light is incident on two silts. The output is an interference pattern. Young's Experiment proved the wave - like nature of light, making the corpuscular theory of light obsolete. Later was repeated with incident electrons instead of photons, bearing the same results, thus giving rise to the particle - wave duality theory and hence, Quantum Mechanics.