Optics Science Olympiad Exam Questions And
Answers
Refractive index or index of refraction - ANSWER -of a material is a
dimensionless number that describes how light propagates through that medium. It
is defined as n = c v , {\displaystyle n={\frac {c}{v}},} where c is the speed of
light in vacuum and v is the phase velocity of light in the medium.
Snell's Law - ANSWER -a formula used to describe the relationship between the
angles of incidence and refraction, when referring to light or other waves passing
through a boundary between two different isotropic media, such as water, glass, or
air.
Critical angle - ANSWER -the angle of incidence for which angle of refraction is
90°. The angle of incidence is measured with respect to the normal at the refractive
boundary (see diagram illustrating Snell's law). Consider a light ray passing from
glass into air.
Prisms - ANSWER -are solid glass optics that are ground and polished into
geometrical and optically significant shapes. The angle, position, and number of
surfaces help define the type and function.
Dispersion - ANSWER -dependent upon the geometry of the prism and its index
dispersion curve, based on the wavelength and index of refraction of the prism
substrate. The angle of minimum deviation dictates the smallest angle between the
incident ray and the transmitted rays (Figure 8). The green wavelength of light is
deviated more than red, and blue more than both red and green; red is commonly
defined as 656.3nm, green as 587.6nm, and blue as 486.1nm.
Deviation - ANSWER -Prisms that deviate the ray path, rotate the image, or
simply displace the image from its original axis are helpful in many imaging
systems. Ray deviations are usually done at angles of 45°, 60°, 90°, and 180°. This
helps to condense system size or adjust the ray path without affecting the rest of
the system setup
, Convex - ANSWER -having an outline or surface curved like the exterior of a
circle or sphere.
Convex lens - ANSWER -Convex lenses are thicker at the middle. Rays of light
that pass through the lens are brought closer together (they converge). A convex
lens is a converging lens. When parallel rays of light pass through a convex lens
the refracted rays converge at one point called the principal focus. A concave lens
is thinner at the centre than at the edges.
Concave - ANSWER -having an outline or surface that curves inward like the
interior of a circle or sphere.
Concave lens - ANSWER -Concave lenses are thinner at the middle. Rays of light
that pass through the lens are spread out (they diverge). A concave lens is a
diverging lens. When parallel rays of light pass through a concave lens the
refracted rays diverge so that they appear to come from one point called the
principal focus. A concave lens is thinner at the centre than at the edges.
Plain mirrors - ANSWER -a mirror with a flat (planar) reflective surface. For light
rays striking a plane mirror, the angle of reflection equals the angle of incidence.
The angle of incidence is the angle between the incident ray and the surface normal
(an imaginary line perpendicular to the surface).
Ray tracing - ANSWER -a technique for generating an image by tracing the path
of light through pixels in an image plane and simulating the effects of its
encounters with virtual objects.
Focal length - ANSWER -the distance between the center of a lens or curved
mirror and its focus.Long is nearsighted, short is farsighted
Real Object - ANSWER -a real image is an image which is located in the plane of
convergence for the light rays that originate from a given object. If a screen is
placed in the plane of a real image the image will generally become visible on the
screen.
Answers
Refractive index or index of refraction - ANSWER -of a material is a
dimensionless number that describes how light propagates through that medium. It
is defined as n = c v , {\displaystyle n={\frac {c}{v}},} where c is the speed of
light in vacuum and v is the phase velocity of light in the medium.
Snell's Law - ANSWER -a formula used to describe the relationship between the
angles of incidence and refraction, when referring to light or other waves passing
through a boundary between two different isotropic media, such as water, glass, or
air.
Critical angle - ANSWER -the angle of incidence for which angle of refraction is
90°. The angle of incidence is measured with respect to the normal at the refractive
boundary (see diagram illustrating Snell's law). Consider a light ray passing from
glass into air.
Prisms - ANSWER -are solid glass optics that are ground and polished into
geometrical and optically significant shapes. The angle, position, and number of
surfaces help define the type and function.
Dispersion - ANSWER -dependent upon the geometry of the prism and its index
dispersion curve, based on the wavelength and index of refraction of the prism
substrate. The angle of minimum deviation dictates the smallest angle between the
incident ray and the transmitted rays (Figure 8). The green wavelength of light is
deviated more than red, and blue more than both red and green; red is commonly
defined as 656.3nm, green as 587.6nm, and blue as 486.1nm.
Deviation - ANSWER -Prisms that deviate the ray path, rotate the image, or
simply displace the image from its original axis are helpful in many imaging
systems. Ray deviations are usually done at angles of 45°, 60°, 90°, and 180°. This
helps to condense system size or adjust the ray path without affecting the rest of
the system setup
, Convex - ANSWER -having an outline or surface curved like the exterior of a
circle or sphere.
Convex lens - ANSWER -Convex lenses are thicker at the middle. Rays of light
that pass through the lens are brought closer together (they converge). A convex
lens is a converging lens. When parallel rays of light pass through a convex lens
the refracted rays converge at one point called the principal focus. A concave lens
is thinner at the centre than at the edges.
Concave - ANSWER -having an outline or surface that curves inward like the
interior of a circle or sphere.
Concave lens - ANSWER -Concave lenses are thinner at the middle. Rays of light
that pass through the lens are spread out (they diverge). A concave lens is a
diverging lens. When parallel rays of light pass through a concave lens the
refracted rays diverge so that they appear to come from one point called the
principal focus. A concave lens is thinner at the centre than at the edges.
Plain mirrors - ANSWER -a mirror with a flat (planar) reflective surface. For light
rays striking a plane mirror, the angle of reflection equals the angle of incidence.
The angle of incidence is the angle between the incident ray and the surface normal
(an imaginary line perpendicular to the surface).
Ray tracing - ANSWER -a technique for generating an image by tracing the path
of light through pixels in an image plane and simulating the effects of its
encounters with virtual objects.
Focal length - ANSWER -the distance between the center of a lens or curved
mirror and its focus.Long is nearsighted, short is farsighted
Real Object - ANSWER -a real image is an image which is located in the plane of
convergence for the light rays that originate from a given object. If a screen is
placed in the plane of a real image the image will generally become visible on the
screen.
