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 and philosopher, Ibn Al-Haytham.
He is the most outstanding physicist of the
Middle Ages and wrote over two
hundred 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 any 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. 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.
In1855, Roger Fenton
used glass plate negatives to take pictures of the British soldiers during the
Crimean War. He developed the plates in his travelling 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 birth place, 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.
P/S: Do change the video quality for a better view.
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