A Lyot
stop (also called a glare stop) is an optical
stop, invented by French astronomer
Bernard Lyot, that reduces the amount of
flare
A flare, also sometimes called a fusée, fusee, or bengala, bengalo in several European countries, is a type of pyrotechnic that produces a bright light or intense heat without an explosion. Flares are used for distress signaling, illuminatio ...
caused by
diffraction
Diffraction is the deviation of waves from straight-line propagation without any change in their energy due to an obstacle or through an aperture. The diffracting object or aperture effectively becomes a secondary source of the Wave propagation ...
of other stops and baffles in
optical systems.
Lyot stops are located at images of the system's
entrance pupil
In an optical system, the entrance pupil is the optical image of the physical aperture stop, as 'seen' through the optical elements in front of the stop. The corresponding image of the aperture stop as seen through the optical elements behin ...
and have a diameter slightly smaller than the pupil's image. Examples of applications can be found in Ref.
See also
*
Lyot filter
*
Lyot depolarizer
*
Coronagraph
A coronagraph is a telescopic attachment designed to block out the direct light from a star or other bright object so that nearby objects – which otherwise would be hidden in the object's bright glare – can be resolved. Most coronagr ...
References
External links
NASA Coronagraphs''Handbook of Optics''
by Bass et al.
Optical devices
Photography equipment
{{Optics-stub