* 1629 – Christiaan Huygens, Dutch mathematician ( d. 1695 )

Diffraction arises because of the way in which waves propagate ; this is described by the Huygens – Fresnel principle and the principle of superposition of waves.

The Huygens – Fresnel principle is one such model ; it states that each point on a wavefront generates a secondary spherical wavelet, and that the disturbance at any subsequent point can be found by summing the contributions of the individual wavelets at that point.

* Christiaan Huygens 1629 – 1695 ( Netherlands )

The Huygens – Fresnel principle provides a good basis for understanding and predicting the wave propagation of light.

The arbitrary assumptions made by Fresnel to arrive at the Huygens – Fresnel equation emerge automatically from the mathematics in this derivation.

The various assumptions made by Fresnel emerge automatically in Kirchhoff's diffraction formula, to which the Huygens – Fresnel principle can be considered to be an approximation.

ro: Principiul Huygens – Fresnel

* Ion and Neutral Camera ( INCA ), an instrument aboard the Cassini – Huygens spacecraft

* 2005 – Landing of the Huygens probe on Saturn's moon Titan.

Among the Laboratory's current major active projects are the Mars Science Laboratory mission ( which includes the Curiosity rover ), the Cassini – Huygens mission orbiting Saturn, the Mars Exploration Rovers ( Spirit and Opportunity ), the Mars Reconnaissance Orbiter, the Dawn mission to the dwarf planet Ceres and asteroid Vesta, the Juno spacecraft en route to Jupiter, the Gravity Recovery and Interior Laboratory ( GRAIL ) mission to the Moon, the Nuclear Spectroscopic Telescope Array ( NuSTAR ) X-ray telescope, and the Spitzer Space Telescope.

* Cassini – Huygens

* 1655 – Saturn's largest moon, Titan, is discovered by Christiaan Huygens.

A second-generation Mariner spacecraft, called the Mariner Mark II series, eventually evolved into the Cassini – Huygens probe, now in orbit around Saturn.

The Huygens – Fresnel equation is one such model.

Examples of the application of Huygens – Fresnel principle can be found in the sections on diffraction and Fraunhofer diffraction.

File: Christiaan Huygens-painting. jpeg | Christiaan Huygens ( 1629-1695 ): studied the rings of Saturn and discovered its moon Titan, invented the pendulum clock, studied optics and centrifugal force, theorized that light consists of waves ( Huygens – Fresnel principle ) which became instrumental in the understanding of wave-particle duality.

* Huygens – Fresnel principle

In the Axioms Scholium of his Principia Newton said its axiomatic three laws of motion were already accepted by mathematicians such as Huygens ( 1629 – 1695 ), Wallace, Wren and others, and also in memos in his draft preparations of the second edition of the Principia he attributed its first law of motion and its law of gravity to a range of historical figures.

The resulting Huygens – Fresnel principle was extremely successful at reproducing light's behavior and, subsequently supported by Thomas Young's discovery of double-slit interference, was the beginning of the end for the particle light camp.

The Cassini – Huygens mission to Titan discovered clouds formed from methane or ethane which deposit rain composed of liquid methane and other organic compounds.

** NASA launches the Cassini – Huygens probe to Saturn.

Augustin-Jean Fresnel did more definitive studies and calculations of diffraction, made public in 1815 and 1818, and thereby gave great support to the wave theory of light that had been advanced by Christiaan Huygens and reinvigorated by Young, against Newton's particle theory.

Wave diffraction in the manner of Huygens and Fresnel

In 1816, Fresnel showed that Huygens ' principle, together with his own principle of interference could explain both the rectilinear propagation of light and also diffraction effects.

Around the same time, Newton's contemporaries Robert Hooke and Christian Huygens — and later Augustin-Jean Fresnel — mathematically refined the wave viewpoint, showing that if light traveled at different speeds in different media ( such as water and air ), refraction could be easily explained as the medium-dependent propagation of light waves.

In the early 19th century, the double-slit experiments by Young and Fresnel provided evidence for Huygens ' wave theories.

According to the Huygens – Fresnel principle, each point on the wavefront of a propagating wave can be considered to act as a point source, and the wavefront at any subsequent point can be found by adding together the contributions from each of these individual point sources.

Huygens achieved note for his argument that light consists of waves, now known as the Huygens – Fresnel principle, which two centuries later became instrumental in the understanding of wave-particle duality.

Huygens ' principle when applied to an aperture simply says that the far-field diffraction pattern is the spatial Fourier transform of the aperture shape, and this is a direct by-product of using the parallel-rays approximation, which is identical to doing a plane wave decomposition of the aperture plane fields ( see Fourier optics ).

However, this article provides an interesting discussion of the limitations of the principle and also of different scientists ' views as to whether it is an accurate representation of reality or whether " Huygens ' principle actually does give the right answer but for the wrong reasons ".

Using Huygens ' theory and the principle of superposition of waves, the complex amplitude at a further point P is found by summing the contributions from each point on the sphere of radius r < sub > 0 </ sub >.

Huygens ' principle can be seen as a consequence of the isotropy of space-all directions in space are equal.

This phenomenon is called Huygens ' principle.

It follows mathematically from Huygens ' principle ( at the limit of small wavelength ), and can be used to derive Snell's law of refraction and the law of reflection.

Classically, Fermat's principle can be considered as a mathematical consequence of Huygens ' principle.

Indeed Fermat's principle does not hold standing alone, we now know it can be derived from earlier principles such as Huygens ' principle.

The probe was supplied by the European Space Agency ( ESA ) and named after the Dutch 17th century astronomer Christiaan Huygens.

Horologium was created in the 18th century by Abbé Nicolas Louis de Lacaille, who originally named it Horologium Oscillitorium after the pendulum clock to honour its inventor, Christiaan Huygens.

* 2801 Huygens, an asteroid named after the astronomer

It is named after Christiaan Huygens, the Dutch astronomer, mathematician and physicist.

The choice of names is often determined by a satellite's discoverer ; however, historically some satellites were not given names for many years after their discovery ; for instance, Titan was discovered by Huygens in 1655, but was not named until 1847, almost two centuries later.

Huygens software is named after the Dutch physicist Christiaan Huygens who is perhaps best known for his argument that light behaves like waves.

wave diffraction plays a key role in the Huygens Software, it was named after him.

Serpentine curves were studied by L ' Hôpital and Huygens, and named and classified by Newton.