Question

what is linear and angular aperture???

Answer 1

Linear aperture is the diameter of the part of the optical system that is exposed to light. Depending upon the optical system the size of the aperture may be fixed or variable. The angular aperture of a lens is defined as the apparent angle of the lens aperture as seen from the focal point.

Answer 2

Answer:

Linear aperture- the effective diameter of the surface of spherical mirror or lens is called linear aperture.

Angular aperture- the angle subtended by the reflecting surface of the spherical mirror or lens at the principal focus is called angular aperture.

See the image below for better understanding

Explanation:

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