Ibn Al-Haytham Muslim scientist who initiated optical cameras

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Ibn Al-Haytham Muslim scientist who initiated optical cameras.

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>Born about a thousand years ago in Iraq today, Al-Hasan Ibn al-Haytham (known in the West in the Latinised form of his first name, originally "Alhacen" and later "Alhazen") was a pioneering scientific thinker who made important contributions to understanding vision, optics and light. His investigative methodology, specifically using experiments to verify theory, shows certain similarities to what became known as modern scientific methods.

History records that a Muslim scientist named Ibn Al-Haytham was the first person to conceptualize an image capture device. This concept was discovered by Ibn Al-Haytham when he was under house arrest by the Fatimid Shah Dynasty which came to power at that time. He also focused on researching the workings of light to capture an image, he also carried out a study that when a small hole was placed in a part of a light-tight box, the light would be projected into the box through the hole.

Ibn Al-Haytham was the first to explain that sight occurs when light bounces on an object and is then directed to one's eyes. He is also an early supporter of the concept that hypotheses must be proven by experiments based on procedures that can be confirmed or mathematical proof, thus understanding the scientific method five centuries before Renaissance scientists.

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Through his book Book of Optics (Kitab al-Manazir) and its Latin translation (De Aspectibus), his ideas influenced European scholars including the European Renaissance. To this day, many consider him an important figure in the history of optics and the "Father of modern optics". Ibn al-Haytham was born during a creative period known as the golden age of Muslim civilization which saw many interesting advances in science, technology and medicine. In an area that spreads from Spain to China, inspiring men and women, from various religions and cultures, are built on knowledge of ancient civilizations, making discoveries that have a great impact and are often underappreciated in our world.

Alhazen's most famous work is his seven-volume treatise on the optics of Kitab al-Manazir (Optical Book), written from 1011 to 1021. Optics were translated into Latin by an unidentified learned man in the late 12th century or early -13. The book was later printed by Friedrich Risner in 1572, with the title Opticae thesaurus: Alhazeni Arabis libri septem, editi nuncprimum; Eiusdem liber De Crepusculis et nubium ascensionibus (in English entitled: Thesaurus of Optical: seven Arabic books of Alhazeni, the first edition: about dusk and progress of the clouds).

Risner is also the author of the name variant "Alhazen", before Risner he was known in the west as Alhacen. This work enjoyed a great reputation during the Middle Ages. The work by Alhazen on geometric subjects was found in the Bibliothèque nationale in Paris in 1834 by E. A. Sedillot. Overall, A. Mark Smith has accounted for 18 complete or near-complete manuscripts, and five fragments, which were kept in 14 locations, including one in the Bodleian Library in Oxford, and one in the Bruges library.

Ibn Al-Haytham discovered the fact that the smaller the hole, the quality of the resulting image can be sharper, this experiment encourages him to create the first camera capable of capturing images sharply and accurately.

Two main theories about vision were expressed in classical antiquity. The first theory, emission theory, was supported by thinkers such as Euclid and Ptolemy, who believed that vision worked with the eyes emitting light rays. The second theory, the intromission theory supported by Aristotle and his followers, has a physical form that enters the eye from objects. Previous Islamic writers (like al-Kindi) basically debated the Euclidean, Galenist, or Aristotle lines. The strongest influence on the Optical Book comes from Ptolemaic Optics, while the description of the anatomy and physiology of the eye is based on calculations from Galen.

Alhazen's achievements were to produce a theory that successfully combined parts of the mathematical arguments of Euclid, Galen's medical tradition, and the intromission theories of Aristotle. Alhazen's intromission theory followed al-Kindi (and broke up with Aristotle's theory) in asserting that "from every point of each colored body, illuminated by any light, emits light and color along each straight line that can be drawn from that point".

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But this leaves it with the problem of explaining how coherent images are formed from many independent radiation sources, in particular, each point of the object sends light to each point in the eye. What Alhazen needed was for each point on an object to fit one point only in the eye. Alhazen tries to solve this by asserting that the eye will only see perpendicular rays from the object - because one point in the eye only sees light reaching directly, without being biased by other parts of the eye, will be felt.

Alhazen argues for using a physical analogy that perpendicular rays are stronger than oblique rays, in the same way that a ball thrown directly on a board can damage the board, whereas a ball thrown on the board glances, the perpendicular beam is stronger than the refractive ray , and that is only the light that is perpendicular to the eye. Because there is only one perpendicular beam that will enter the eye at one point, and all these rays will gather in the center of the eye in a cone, this allows him to solve the problem of every point on the object that sends a lot of light into the eye, if only the beam is upright straight meaningful, then he has one-to-one correspondence and the confusion can be resolved. Alhazen then asserted (in book seven Optics) that other rays will be refracted through the eyes and felt as if they are perpendicular.

His argument about perpendicular rays does not clearly explain why only perpendicular rays are felt; why weaker oblique rays are not considered weaker. His opinion later that the refractive rays will be felt as if perpendicular does not seem persuasive. However, despite its weaknesses, there was no other theory at that time that was so comprehensive, and it was very influential, especially in Western Europe: Directly or indirectly, De Aspectibus (Book of Optics) inspired many activities in optics between the 13th and 17th centuries . Then Kepler's theory (a mathematician, astronomer and an astrologer) argues that the image of the retina (which resolves the problem of correspondence points on objects and points in the eye) is built directly on the conceptual framework of Alhazen.

Alhazen shows through experiments that light moves in a straight line, and performs various experiments with lenses, mirrors, refraction, and reflection. Analysis of its reflection and refraction consider the horizontal and vertical light components separately.

Alhazen studied the process of vision, the structure of the eye, the formation of shadows in the eye, and the visual system. Ian P. Howard argues in a 1996 Perception article that Alhazen must be rewarded with many discoveries and theories previously associated with writing in Western Europe a few centuries later. For example, he described what became the same law of salvation in the 19th century from Hering. He wrote a description of vertical horopters 600 years before Aguilonius which was actually closer to the modern definition than Aguilonius's and his work on binocular disparity was repeated by Panum in 1858. Craig Aaen-Stockdale, while agreeing that Alhazen should be rewarded with much progress, had made several warnings , especially when considering Alhazen in isolation from Ptolemy, which Alhazen was very familiar with.