the second course of light

aberration aether air film amplitude aperture astigmatism blue bright Calculate camera centre chromatic colour concave mirror converging lens convex cross-wires crystal curve dark deviation diameter diffraction pattern direction equal equation exit pupil Explain eye lens eyepiece field of view film final image focal length focus Fraunhofer Fraunhofer diffraction Fraunhofer lines Fresnel Fresnel diffraction grating green hence Huygens illumination image formed infra-red interference fringes lamp lens of focal lenses lumens luminous flux luminous intensity magnifying power measured Michelson microscope Newton's rings normal observed optic axis path difference perpendicular photographic photometer polarised light polaroid position prism produced radiation radius of curvature rays real image reflected refractive index retina right angles rotation S₁ screen simple harmonic motions slit spectral lines spectrum spherical spherical aberration surface telescope thickness thin transmitted ultra-violet velocity of light vibrations violet wave-front white light width yellow zones