41. Roger Bacon Et Kepler Lecteurs D'Alhazen http://www.univ-lille3.fr/www/Recherche/set/sem/SimonResume.html

Optique Perspectiva et la Multiplicatio specierum species Il faudra attendre 1604 pour que Kepler renouvelle l'optique ( Paralipomena ad Vitellionem ), en relisant Descartes et le Moyen Age , Paris, Vrin, 1997. -Jeremiah Hackett (ed.), Roger Bacon and the Sciences. Commemorative Essays , Leyden- New-York, Brill, 1997. - David C. Lindberg, Theories of vision from al-Kindi to Kepler , The University of Chicago Press, 1976. - Roshdi Rashed, , Paris, Les belles Lettres, 1993. Edition et traduction d'oeuvres optiques d'Ibn Sahl, d'al-Quhi, d'Ibn al-Haytham (extraits du livre VII du Kitab al-Manazir ), d'al-Farisi., avec intr. et notes. , Paris, Seuil, 1988. , Lille, Septentrion, 1996. -Katherine H. Tachau, Vision and Perspective in the Age of Okham , Brill, Leyde, 1988.

42. Alhazen | 965-1039 | Ibn Al-Haytham, Arab Mathematician And Physicist alhazen 9651039 Ibn al-Haytham, Arab mathematician and physicist.Problema alhazeni (1685-1695); Slusius de Probl alhazeni (1685-1695). http://www.nahste.ac.uk/pers/a/GB_0237_NAHSTE_P2171/

the project the collections biographies multimedia the project the collections biographies multimedia ... Slusius de Probl: Alhazeni

43. Natur Des Lichts Translate this page alhazen. alhazen (965 bis ca. 1040), arabischer Gesichtssinn. Die bedeutendstenBeiträge leistete alhazen auf dem Gebiet der Optik. Er http://members.aol.com/mblicht1/alhazen.htm

Alhazen Alhazen (965 bis ca. 1040), arabischer Wissenschaftler und Naturforscher, mit vollem Namen Abu Ali Al-Hasan Ibn Al-Haitham, der über 200 Werke zur Optik, Astronomie und Mathematik schrieb. Sein Hauptwerk Große Optik enthält Beschreibungen und Erklärungen zum Licht und zum Gesichtssinn. Die bedeutendsten Beiträge leistete Alhazen auf dem Gebiet der Optik. Er entwickelte eine umfassende Theorie, die das Sehvermögen mittels Geometrie und Anatomie erklärte. Nach dieser Theorie strahlt jeder Punkt auf einer beleuchteten Fläche Licht in alle Richtungen aus; aber nur ein Strahl von jedem Punkt, und zwar derjenige, der senkrecht auf das Auge trifft, kann gesehen werden. Licht beschrieb er als Form der Bewegung, die in verschiedenen Substanzen verschiedene Geschwindigkeiten hat. Von ihm stammt auch die sogenannte "Alhazensche Aufgabe" : Zwei Punkten liegt eine spiegelnde Oberfläche gegenüber; gesucht ist der Punkt auf der Oberfläche des Spiegels, der einen Lichtstrahl, welcher aus einem der gegebenen Punkte austritt, auf den anderen reflektiert. Auf dem Gebiet der Astronomie ergänzte Alhazen die Theorien des Astronomen Ptolemäus aus dem 2. Jahrhundert n. Chr. Er faßte außerdem einige mathematische Lehrsätze des griechischen Mathematikers Euklid zusammen.

44. Natur Des Lichts Translate this page Besondere Bedeutung in der Optik hatte Ibn Al Haitam (alhazen). alhazenstellte sich das Sehen als Empfang von Lichtstrahlen vor http://members.aol.com/mblicht1/mittelal.htm

Mittelalter und Renaissance Während das Christentum zu Beginn seiner Ausbreitung wenig wissenschaftsfreundlich war, sammelten und übersetzten Araber die antiken Schriften und leisteten eigene wissenschaftliche Beiträge. Besondere Bedeutung in der Optik hatte Ibn Al Haitam (Alhazen). Alhazen stellte sich das Sehen als Empfang von Lichtstrahlen vor, die von jedem Punkt eines leuchtenden oder beleuchteten Gegenstands ausgehen - er widersprch damit der bis dahin verbreiteten Sehstrahltheorie. Mit dieser Vorstellung erklärte er die Bildentstehung bei der Camera obscura und wieß in Versuchen nach, dass sich das Licht geradlinig ausbreitet und sich kreuzende Lichtstrahlen nicht gegenseitig beeinflussen. Die Lichtausbreitung verstand Alhazen als "Bewegung" mit sehr hoher, aber endlicher Geschwindigkeit. Diese sei in einem dichteren Medium geringer, da die Lichtausbreitung durch das Medium behindert werde. Reflexion und Brechung versuchte er schon mit einem mechanischen Modell zu erklären, nämlich dem Aufprall einer Kugel auf eine Wand bzw. ihrem Eindringen. Ab etwa dem 12. Jahrhundert verlagert sich der wissenschaftliche Schwerpunkt wieder aus dem Osten in den Westen. Zunächst wurden aber im Wesentlichen die Schriften von Alhazen, Ptolemäus und Euklid übersetzt und zusammengefasst.

45. Alhazen, Ibn Al-Haytham alhazen, Ibn alHaytham (c. 965-1038). (Abu al-Hassan ibn al-Haytham Eastand West. alhazen was born in Basra (now in Iraq). He made many http://www.cartage.org.lb/en/themes/Biographies/MainBiographies/A/Alhazen/1.html

Alhazen, Ibn al-Haytham (c. 965-1038) (Abu al-Hassan ibn al-Haytham) Arab scientist, author of the Kitab al-Manazir/Book of Optics, translated into Latin as Opticae thesaurus (1572). For centuries it remained the most comprehensive and authoritative treatment of optics in both East and West. Alhazen was born in Basra (now in Iraq). He made many contributions to optics, contesting the Greek view of Hero and Ptolemy that vision involves rays that emerge from the eye and are reflected by objects viewed. Alhazen postulated that light rays originate in a flame or in the Sun, strike objects, and are reflected by them into the eye. He studied lenses and mirrors, working out that the curvature of a lens accounts for its ability to focus light. He measured the refraction of light by lenses and its reflection by mirrors, and formulated the geometric optics of image formation by spherical and parabolic mirrors. He constructed a camera obscura. He also tried to account for the occurrence of rainbows, appreciating that they are formed in the atmosphere, which he estimated extended for about 15 km/9 mi above the ground.

46. IDENTIKIT Name Size Coordinates Image. alhazen crater, 35 km diameter 2000 mt heightwalls. 18°N 70°E Eastern side of Crisium sea. Return to identikit A . http://www.rccr.cremona.it/monografie/luna/idkt11.htm

IDENTIKIT Name: Size: Coordinates: Image ALHAZEN crater 35 km diameter 2000 mt height walls 18°N - 70°E Eastern side of Crisium sea >> Return to identikit "A" <<

47. Alhazen Translate this page Bürgerforum Rosenheim alhazen. http://www.rosenheim.de/forum/messages/2626.html

alhazen Hilfe Gesendet von emma am 08. Dezember 2002 um 16:06:15 hallo Name: E-Mail: Betreff: Nachricht: Optionale Link URL: Titel des Links: Optionale Grafik URL:

48. Alhazen Wynalazcy. alhazen Ibn alHaitham. arabski matematyk, fizyk i astronom dzialajacyw Egipcie (ok. 965-1039). Pionier optyki, wg. tradycji wynalazca soczewki. http://zso.slomniki.ids.pl/wynalazki/twor/alhazen.html

Wynalazcy Alhazen Ibn al-Haitham. arabski matematyk, fizyk i astronom dzia³aj±cy w Egipcie (ok. 965-1039). Pionier optyki, wg. tradycji wynalazca soczewki By³ pierwszym, który opisywa³ " ciemniê optyczn± " - pierwowzór aparatu fotograficznego i proponowa³ jej u¿ycie do obserwacji zaæmieñ s³oñca. Interesowa³ siê zjawiskami optycznymi - za³amanie ¶wiat³a. Do strony g³ównej

49. Al-Haitham (Alhazen), 965-1040 CE ABU ALI HASAN IBN ALHAITHAM (alhazen) (965 - 1040 CE), by Dr. A. Zahoor. Al-Haitham,known in the West as alhazen, is considered as the father of modern Optics. http://www.uaepages.com/leo/ibnalhaytham.htm

50. Leben Und Verdienst Ibn Al-Haithams Translate this page Verständnis im Mittelalter. Ibn al-Haitham, im Mittelalter auch alhazengenannt, teilte sein optisches Meisterwerk in sieben Bücher http://www.optiker.at/archiv/museum/alhazen/alhazen.htm

Leben und Verdienst Ibn al-Haithams in Zusammenhang mit der Entwicklungsgeschichte des Lesesteins und der Brille Erfindung der Brille Archimedes , Apollonius, Ptolemaeus, Euklid, Porphyrius und Diophantus. Lesestein Lesestein Frescos von Tommaso di Modena aus dem Jahre 1439. Optiker Online webmaster@optiker.at Literatur: [1.] Die Sehhilfe im Wandel der Jahrhunderte, Emil Heinz Schmitz, 1961 [3.] Naturwissenschaft und Technik: Schall, Bild, Optik, Zweiburgen, 1991 [4.] Die Brille, Frank Rossi, 1989 Die Visby-Linsen , Olaf Schmidt, Karl-Heinz Wilms und Bernd Lingelbach, DOZ 11/98 [7.] Die Optik und die optischen Instrumente, Karl Gentil, 1927 [8.] Geschichte der Optik, Edmund Hoppe, 1926 [9.] Handbuch zur Geschichte der Optik, E.-H. Schmitz, Die Brille, J.P. Wayenborgh, 1995

51. Index Of /archiv/museum/alhazen Index of /archiv/museum/alhazen. Parent Directory 21Feb-2000 0212 -alhazen.htm 25-Feb-1999 1757 13k ibnauge.gif 25-Feb-1999 1733 7k http://www.optiker.at/archiv/museum/alhazen/

Index of /archiv/museum/alhazen Name Last modified Size Description ... Parent Directory 21-Feb-2000 02:12 - alhazen.htm 25-Feb-1999 17:57 13k ibnauge.gif 25-Feb-1999 17:33 7k

52. Alhazen alhazen's Billiard Problem. It was first formulated by Ptolemy in 150 AD, and wasnamed after the Arab scholar alhazen who discussed it in his work on optics. http://poncelet.math.nthu.edu.tw/chuan/html/Alhazen.html

Alhazen's Billiard Problem In a given Circle, find an Isosceles Triangle whose Legs pass through two given Points inside the Circle. This can be restated as: from two Points in the Plane of a Circle, draw Lines meeting at the Point of the Circumference and making equal Angles with the Normal at that Point. This is called the billiard problem because it corresponds to finding the Point on the Edge of a circular ``Billiard'' table at which a cue ball at a given Point must be aimed in order to carom once off the Edge of the table and strike another ball at a second given Point. The solution leads to a Biquadratic Equation of the form The problem is equivalent to the determination of the point on a spherical mirror where a ray of light will reflect in order to pass from a given source to an observer. It was first formulated by Ptolemy in 150 AD, and was named after the Arab scholar Alhazen who discussed it in his work on optics. It was not until 1997 that Neumann proved the problem to be insoluble using a Compass and Ruler construction because the solution requires extraction of a Cube Root. This is the same reason that the

53. Physics Alhazen Alhazen (c. 965 AD - C. 1039; Iraq) Alhazen Is Physics alhazen. alhazen (c. 965 AD c. 1039; Iraq). alhazen is regardedas being one of the greatest Islamic scientists during the http://www.upei.ca/~xliu/multi-culture/alha.htm

Physics Alhazen Alhazen (c. 965 A.D. - c. 1039; Iraq) Alhazen is regarded as being one of the greatest Islamic scientists during the medieval period and has been credited as being the first person to give an accurate description of how humans see. Although he was born in Iraq, Alhazen moved to Egypt between 996 and 1021and remained there until his death in 1039. Alhazen's greatest contribution to the field of physics was his work entitled, Optics, in which Alhazen took Euclid's and Ptolemy's doctrines on visual rays and replaced them with his own belief that vision was the result of light coming from an object and moving into the eye. Alhazen thought that rays reached the surface of the eye perpendicularly and the combined effects from the perpendicular rays formed the image of the object.This hypothesis was based on Alhazen's theory that all objects reflected light in every direction. All of the observations and experiments used in his work related to the camera obscura, perception, visual illusions, reflection and refraction and were heavily based upon mathematics. In regard to his work on refraction, Alhazen wrote in his book that refraction explained twilight. Alhazen stated that twilight was due to the refraction of the sun's rays in the earth's atmosphere. During his work on Optics, which was translated into Latin in 1270, Alhazen developed a problem which involved curved mirrors and reflected light. Alhazen was able to solve this problem, which bears his name, for spherical mirrors through the method of intersecting a circle and hyperbola.

54. Off Topic (non Total War Disscussions) 97, 2/6/03 23344 pm by PolskaPower, alhazen AlRashid. US military tired of USmade rifles. 10, 2/6/03 121431 pm by alhazen AlRashid, Boondock the Saint. http://pub24.ezboard.com/fshoguntotalwarfrm3

"); else document.write(""); // > Total War > Off topic (non Total War disscussions) Invite Friends! Moderated by: Shadelord Tarrak The Critter Speaks Wart ... Need help logging in? 19 visitors in the last 15 minutes: 4 Members - 15 Guests - Anonymous Coachbdw hZ Sanity SHADOW PRAETORIAN Page Topic Replies Last Comment Started By Forum Rules and Guidelines 3/3/03 5:45:12 pm The Critter Speaks An elephant on steroids in a chinashop 3/29/03 4:58:51 am by: Efrem Da King Guddy ODS Militant Order Hagiographers St Jusofabulous + sheep relics 3/29/03 4:47:46 am by: navy75 Why did Shakespeare... 3/29/03 3:37:29 am xenocidemesomeone Favorite Quotes 3/29/03 3:33:17 am by: xenocidemesomeone LeoKrause Poll: Military vs. Bush 3/29/03 3:25:46 am by: xenocidemesomeone xenocidemesomeone TO:Protesters 3/29/03 3:13:18 am by: Person41 Yearning... 3/29/03 2:59:55 am by: navy75 Jurand Hey all you Anti-War Boys 3/29/03 2:45:04 am by: Alhazen AlRashid HattoriGladiator Our American John Keegan 3/29/03 2:09:36 am by: PolskaPower Wencelas Bashing the US over the International Court? 3/29/03 1:53:54 am by: Mellow Horde Alhazen AlRashid To kill or not to kill...

55. Off Topic (non Total War Disscussions) 8, 1/28/03 30807 pm by Papa Bear, alhazen AlRashid. US Planning to DeclassifyIntelligence on IRAQ, 0, 1/28/03 63602 am, alhazen AlRashid. Ode Tae a Fert! http://pub24.ezboard.com/fshoguntotalwarfrm3?page=6

56. Islam Online- News Section alhazen Master of Optics. Charged with the nearimpossible task, alhazenled an army of worker south of Aswan to the place called al-Janadil. http://www.islamonline.net/english/Science/2001/08/article11.shtml

Home About Us Media Kit Contact Us ... Your Mail Search Advanced Search News Iraq Special Special Pages Islam Ask about Islam Contemporary Issues My Journey to Islam Qur'an Fatwa Fatwa Bank Ask the Scholar Live Fatwa Counseling Cyber Counselor Directories Site Directory Islamic Society Islamic Banks TV Channels ... Telephone Code Services Matrimonial Date Converter Calendar Discussion Forum ... E-Cards Newsletter Enter your E-mail Alhazen: Master of Optics By David W. Tschanz The brightest name in Egyptian Islamic science is that of mathematician and scholar Abu 'Ali al-Hasan bin al-Hasan bin al-Haytham, known as "Alhazen" to the Western world. Born in Basra, Iraq in 965, he won repute there as a mathematician and engineer. He was invited to move to Cairo, Egypt by the Fatimid Caliph, al-Hakim. According to one story al-Hakim had invited Alhazen because it was believed that the mathematician had a plan for regulating the waters of the Nile. Charged with the near-impossible task, Alhazen led an army of worker south of Aswan to the place called al-Janadil. Here he expected to see the Nile's waters descending from higher ground and was disappointed when he discovered they did not. According to a 13th century account, Alhazen feared that the eccentric and unpredictable al-Hakim would punish him for his failure. To avoid punishment, he pretended to be insane until al-Hakim's death. He then left the house in which he had been confined and moved to a qubbah (a small domed structure) at the gate of Cairo's Azhar Mosque. There he resumed his work as an author and teacher of mathematics. He earned his living by copying a number of basic mathematical works, which included Euclid's

57. Islam Online- News Section alhazen's most important work is the comprehensive Kitab alManazir (The Book ofOptics), probably the most thoroughly scientific, in method and thought, of http://www.islamonline.net/english/Science/2001/03/article7.shtml

Home About Us Media Kit Contact Us ... Your Mail Search Advanced Search News Iraq Special Special Pages Islam Ask about Islam Contemporary Issues My Journey to Islam Qur'an Fatwa Fatwa Bank Ask the Scholar Live Fatwa Counseling Cyber Counselor Directories Site Directory Islamic Society Islamic Banks TV Channels ... Telephone Code Services Matrimonial Date Converter Calendar Discussion Forum ... E-Cards Newsletter Enter your E-mail Unlocking The Secrets Of Sight By David Tschanz Edited by Karima Burns The hot and dusty plains of the Middle East have always created an environment in which endemic diseases of the eye such as trachoma and ophthalmia are unusually prevalent. During the Middle Ages, blindness was the leading cause of disability throughout the Islamic world, and an extensive specialist literature developed in medieval Islamic medical art. Nearly every medical compendium had chapters on eye diseases, but the most comprehensive coverage was provided in a large number of monographs devoted solely to the subject. Thus, through their daily practices and gradually improved techniques, Arab physicians and oculists attained a level of proficiency in understanding and treating the diseases of the eye that would not be matched by anyone else in the world for seven centuries. Hunayn bin Ishaq's 9th Century Ten Treatises on the Eye was one of the earliest and most influential of these, and correctly described the process by which light enters the eye and allows vision to occur. Every aspect of his theory of sight was correct except that Hunayn did not realize that the eye receives an inverted image that the brain turns 180 degrees.

58. Alhazen - Wikipedia Similar pages alhazen http://www.wikipedia.org/wiki/Alhazen

Main Page Recent changes Edit this page Older versions Special pages Set my user preferences My watchlist Recently updated pages Upload image files Image list Registered users Site statistics Random article Orphaned articles Orphaned images Popular articles Most wanted articles Short articles Long articles Newly created articles Interlanguage links All pages by title Blocked IP addresses Maintenance page External book sources Printable version Talk Log in Help Alhazen From Wikipedia, the free encyclopedia. Alhazen (Abu Ali al-Hasan Ibn Alhasan) ) was an Arabian mathematician of the 11th century. He was born at Basra and died at Cairo . He is to be distinguished from another Alhazen who translated Ptolemy 's Almagest in the 10th century. Having boasted that he could construct a machine for regulating the inundations of the Nile , he was summoned to Egypt by the caliph Hakim; but, aware of the impracticability of his scheme, and fearing the caliph's anger, he feigned madness until Hakim's death in 1021. Alhazen was nevertheless a diligent and successful student, being the first great discoverer in optics after the time of Ptolemy. According to Giovanni Battista della Porta, he first explained the apparent increase of heavenly bodies near the horizon, although Bacon gives the credit of this discovery to Ptolemy. He taught, previous to the Polish physicist Witelo, that vision does not result from the emission of rays from the eye, and wrote also on the refraction of light, especially on atmospheric refraction, showing, e.g. the cause of morning and evening twilight. He solved the problem of finding the point in a convex mirror at which a ray coming from one given point shall be reflected to another given point. His treatise on optics was translated into Latin by Witelo (1270), and afterwards published by F. Risner in 1572, with the title

59. Editorial Perception 1996, volume 25 Guest editorial. The deeper lesson of alhazen Iwill take alhazen and Wallach to represent these two time frames. (1). http://www.perceptionweb.com/perc1096/editorial.html

Perception 1996, volume 25 Guest editorial The deeper lesson of Alhazen This special historical issue of Perception concerns the neglect of vision work in other times and other places. The contents fall into two groups: the writings of Ptolemy and Alhazen in Egypt many centuries ago, and the more recent writings of nineteenth and early twentieth century German scholars. I will take Alhazen and Wallach to represent these two time frames. As regards the former, we are indebted to Ian Howard for his provocative reminder of the groundbreaking work of Alhazen. In Alhazen we find an astonishing range of insights that we have been in the habit of crediting to far more recent Westerners. Some six hundred years before Galileo he was conducting experiments, even psychophysical experiments. His work provided the basis for Kepler's correct explanation of the formation of retinal images as the first stage of vision, surely a cornerstone of the entire modern discipline of visual perception. It was the apparent discrepancy between the properties of retinal images and the properties of the visual world that demanded explanation, animating the field of visual perception then and now. How could so important a figure have been so badly neglected? If Alhazen is obscure in our field, the same cannot be said of Hans Wallach, who is known for many elegant experiments. In his study of the kinetic depth effect Wallach established a new depth cue-motion-in such a characteristically convincing way that his claim has never even been challenged. First, he showed that the display appeared to have depth only when in motion, while any stationary view appeared flat. Second, because the stimulus was in fact a flat silhouette, most depth cues were ruled out as causal factors even though they were not excluded from the laboratory conditions.

60. Perception: ECVP 2001 Abstracts Perception ECVP 2001 abstracts ECVP 2001 abstract. alhazen. Almost 1000 yearsago alhazen presented the first truly modern theory of perception. http://www.perceptionweb.com/ecvp01/0049.html

Perception : ECVP 2001 abstracts ECVP 2001 abstract Alhazen. The roots of unconscious inference P Cavanagh (Department of Psychology, Harvard University, 33 Kirkland Street, Cambridge, MA 02138, USA; e-mail: patrick@wjh.harvard.edu

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