Risner is also the author of the name variant"Alhazen";
Alhazen's contributions to number theory include his work on perfect numbers.
Alhazen solved problems involving congruences using what
is now called Wilson's theorem.
Alhazen eventually solved the problem using conic sections
and a geometric proof.
In general, Alhazen built on and expanded the optics of Ptolemy.
Alhazen's problem can also be extended to multiple refractions from
a spherical ball.
Alhazen wrote as many as 200 books, although only 55 have survived.
In his work, Alhazen discussed theories on the motion of a body.
Toomer does concede that“Schramm sums up[Alhazen's] achievement in the development of scientific method.”.
Alhazen also discussed space perception
and its epistemological implications in his Book of Optics.
Alhazen was a Muslim;
it is not certain to which school of Islam he belonged.
Alhazen believed there was a"true configuration" of the planets
that Ptolemy had failed to grasp.
Alhazen's The Model of the Motions of Each of the Seven Planets was written c.
Legend has it that Alhazen feigned madness
and was kept under house arrest during this period.
Smith(2010) has noted that Alhazen's treatment of refraction describes an experimental setup without publication of data.
Alhazen corrected a significant error of Ptolemy regarding binocular vision,
but otherwise his account is very similar;
In the 10th century, Ibn al-Haytham(Alhazen) performed several physical experiments,
mainly in optics, achievements still celebrated today.
Alhazen argued against Ptolemy's refraction theory, and defined
the problem in terms of perceived, rather than real, enlargement.
Alhazen's most famous work is his seven-volume treatise
on optics Kitab al-Manazir(Book of Optics), written from 1011 to 1021.
Although Alhazen is often credited with the perceived distance explanation,
he was not the first author to offer it.
In his Opuscula, Alhazen considers the solution of a system of congruences,
and gives two general methods of solution.
Alhazen studied the process of sight,
the structure of the eye, image formation in the eye, and the visual system.
Ibn Al-Haytham,
in Europe more commonly called by his Latinized name“Alhazen”, was born in the city of Busra in 965.
Khaleefa has also argued that Alhazen should also be considered the"founder of psychophysics", a
sub-discipline and precursor to modern psychology.
Over forty years previously, Jacob Bronowski presented Alhazen's work in a similar television documentary(and the corresponding book),
The Ascent of Man.
In his On the Configuration of the World Alhazen presented a detailed description of the physical structure of the earth:.
Alhazen showed through experiment that light travels in straight lines,
and carried out various experiments with lenses, mirrors, refraction, and reflection.
In honour of Alhazen, the Aga Khan University(Pakistan)
named its Ophthalmology endowed chair as"The Ibn-e-Haitham Associate Professor and Chief of Ophthalmology.
Alhazen's synthesis of light and vision adhered to the Aristotelian scheme,
exhaustively describing the process of vision in a logical, complete fashion.
Alhazen offered an explanation of the Moon illusion,
an illusion that played an important role in the scientific tradition of medieval Europe.