Corpuscular Theory of Light
In optics, corpuscular theory of light, originally set forward by Pierre Gassendi, states that light is made up of small discrete particles called "corpuscles" (little particles) which travel in a straight line with a finite velocity and possess kinetic energy.
It was largely developed by Sir Isaac Newton. Newton's theory remained in force for more than 100 years and took precedence overHuygens' wave front theory, partly because of Newton’s great prestige. However when the corpuscular theory failed to adequately explain the diffraction, interference and polarization of light it was abandoned in favour of Huygen's wave theory.[1]
Newton's corpuscular theory was an elaboration of his view of reality as interactions of material points through forces. Note Albert Einstein's description of Newton's conception of physical reality:
[Newton's] physical reality is characterised by concepts of space, time, the material point and force (interaction betweenmaterial points). Physical events are to be thought of as movements according to law of material points in space. Thematerial point is the only representative of reality in so far as it is subject to change. The concept of the material point is obviously due to observable bodies; one conceived of the material point on the analogy of movable bodies by omitting characteristics of extension, form, spatial locality, and all their 'inner' qualities, retaining only inertia, translation, and the additional concept of force.[2][3]
The Huygens–Fresnel principle (named after Dutch physicist Christiaan Huygens and French physicist Augustin-Jean Fresnel) is a method of analysis applied to problems of wave propagation both in the far-field limit and in near-field diffraction.
In 1678, Huygens[1] proposed that every point to which a luminous disturbance reaches becomes a source of a spherical wave; the sum of these secondary waves determines the form of the wave at any subsequent time. He assumed that the secondary waves
It was largely developed by Sir Isaac Newton. Newton's theory remained in force for more than 100 years and took precedence overHuygens' wave front theory, partly because of Newton’s great prestige. However when the corpuscular theory failed to adequately explain the diffraction, interference and polarization of light it was abandoned in favour of Huygen's wave theory.[1]
Newton's corpuscular theory was an elaboration of his view of reality as interactions of material points through forces. Note Albert Einstein's description of Newton's conception of physical reality:
[Newton's] physical reality is characterised by concepts of space, time, the material point and force (interaction betweenmaterial points). Physical events are to be thought of as movements according to law of material points in space. Thematerial point is the only representative of reality in so far as it is subject to change. The concept of the material point is obviously due to observable bodies; one conceived of the material point on the analogy of movable bodies by omitting characteristics of extension, form, spatial locality, and all their 'inner' qualities, retaining only inertia, translation, and the additional concept of force.[2][3]
The Huygens–Fresnel principle (named after Dutch physicist Christiaan Huygens and French physicist Augustin-Jean Fresnel) is a method of analysis applied to problems of wave propagation both in the far-field limit and in near-field diffraction.
In 1678, Huygens[1] proposed that every point to which a luminous disturbance reaches becomes a source of a spherical wave; the sum of these secondary waves determines the form of the wave at any subsequent time. He assumed that the secondary waves