THE camera is one of the most powerful instruments ever invented. Still photographs and moving pictures have provided man the ability to record and display images of every kind - from the first few cells of a human embryo to galaxies, billions of light years away. But did you know that the principles, on which all cameras are based, were laid down around one thousand years ago by the Muslim scientist, Ibn Al-Haytham? Ibn Al-Haytham was born in Basra (in modern-day Iraq) in 965 CE and died in Cairo in 1039 CE. He is the most outstanding physicist of the Middle Ages and wrote over 200 scientific works. Although he made important contributions to mathematics, astronomy, medicine and chemistry, his most outstanding achievements were in physics and optics. He was the founder of modern physics in the true sense of the word. He anticipated by six centuries the fertile ideas that were to mark the outset of this branch of science. It was Ibn Al-Haytham who first discovered that light travels in straight lines. In refraction his outstanding contribution was the application of the rectangle of velocities at the surface of refraction, six centuries before Isaac Newton (1642 - 1727). Al-Bayt Al-Muzlim or camera obscura, the Arabic and Latin words, respectively, for a darkroom, was the prototype of the modern photographic camera. It worked on the principle that rays of light, reflected from an illuminated object will pass through a tiny hole in a dark room and project the image of the object upside down on a wall inside the room. It was a revolutionary invention in the field of optics. The term camera obscura was first used in Western scientific literature by Joseph Kepler (1571 - 1630). In the third chapter of the first volume of Kitab Al-Manazir (The Book of Optics), Ibn Al-Haytham examines the moon's capacity to emit light without itself being a polished mirror. This led to the discovery that all coloured bodies emit light, and that light and colour are virtually identical. In his experiments to prove these theories he constructed the Al-Bayt Al-Muzlim which consisted of a darkened room with a small aperture in one wall, through which an inverted image was projected onto the opposite wall. The viewer was inside the room. This type of device was also used by Ibn Al-Haytham and his students for their astronomical studies on sunspots and other solar and lunar phenomena. About 500 years later, Geronimo Cardano (1501 -1576), who was influenced by Ibn Al-Haytham, suggested replacing the small aperture with a lens. Credit for the introduction of a lens to the camera obscura goes to Giovanni Batista della Porta (1535 - 1615). Kepler improved it with a negative lens behind the positive lens which enlarged the projected image (the principle used in the modern telephoto lens). Robert Boyle (1627 - 1691) was the first to construct a small, portable, box-type camera obscura in 1665. Artists and architects used the device to give a realistic perspective to their work. Two scientific principles had to be combined to make photography possible - one optical, the other chemical. It was 900 years after Ibn Al-Haytham's invention that photographic plates were first used to permanently capture the image produced by the camera obscura. The first permanent photograph was taken by Joseph Nicephore Niepce in France in 1827. In 1888, George Eastman developed a convenient, light-sensitive film and introduced the Kodak camera which made possible modern-day photography. In 1855, Roger Fenton used glass plate negatives to take pictures of the British soldiers during the Crimean War. He developed the plates in his traveling dark room – a converted wagon. A version of the camera obscura was used in the First World War for aircraft spotting and performance measurement, and in the Second World War for checking the accuracy of radio navigation devices. What an irony it is that a thousand years after Ibn Al-Haytham, his own birthplace, Basra, was destroyed using Tomahawk missiles which are camera-guided. Satellites mapped the Iraqi terrain using cameras and then transmitted the information to missiles, fired from the USS Wisconsin, guiding them to their targets.
