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v Muslim Inventions that shaped Modern Day World #1 Camera
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The ancient Greeks thought our eyes emitted rays, like a laser, which enabled us to see. The first person to realise that light enters the eye, rather than leaving it, was the 10th-century Muslim mathematician, astronomer and physicist Ibn al-Haitham. He invented the first pin-hole camera after noticing the way light came through a hole in window shutters. The smaller the hole, the better the picture, he worked out, and set up the first Camera Obscura (from the Arab word qamara for a dark or private room). This idea laid the foundation of the present day Camera.
IBN AL-HAYTHAM
(965 in Basra - c. 1039 in
Cairo )
Known in the West as Alhazen, Alhacen, or Alhazeni,
Ibn al-Haytham was
the first person to test hypotheses with verifiable experiments,
developing the scientific method more than 200 years
before European scholars learned of
it—by reading his books.
He was also nicknamed Ptolemaeus Secundus ("Ptolemy the Second").
Ibn al-Haytham is regarded as the “father of modern optics” for his
influential Book of Optics (Kitâb
al-Manâzir ).
Like many eminent philosophers and mathematicians, Ibn
Al-Haytham was a keen observer. While in a room one day he noticed light coming
through a small hole made in the window shutters. It fell onto the wall
opposite and it was the half-moon shape of the sun’s image during eclipses. He
said: ‘The image of the sun at the time of the eclipse, unless it is total,
demonstrates that when its light passes through a narrow, round hole and is
cast on a place opposite to the hole it takes on the form of a moon-sickle.’
From his experiments, he explained that light travelled in a
straight line and when the rays were reflected off a bright subject they passed
through the small hole and did not scatter but crossed and reformed as an
upside-down image on a flat white surface parallel to the hole. He then established
that the smaller the hole, the clearer the picture.
His experimental conclusions were that when the sunlight reached
and penetrated the hole, it made a conic shape at the meeting point with the
pinhole, and later formed another conic shape in reverse to the first one on
the opposite wall in the dark room.
‘Light issues in all directions opposite any body that is
illuminated with any light [and of course, also opposite any self-luminous
body]. Therefore when the eye is opposite a visible object and the object is
illuminated with light of any sort, light comes to the surface of the eye from
the light of the visible object.’ (10th-century Ibn al-Haytham from his ‘Book
of Optics)
Ibn al-Haytham (Alhazen) wrote about
naturally-occurring rudimentary pinhole cameras.
For example, light may travel through the
slits of wicker baskets or the crossing of tree leaves.[1] (The circular
dapples on a forest floor, actually pinhole images of the sun, can be seen to
have a bite taken out of them during partial solar eclipses opposite to the
position of the moon's actual occultation of the sun because of the inverting
effect of pinhole lenses.)
Alhaitham published this idea in the
"Book of Optics" in 1021 AD. He improved on the camera after
realizing that the smaller the pinhole, the sharper the image (though the less
light).
He provides the first clear description for
construction of a camera obscura (Lat. dark chamber).
A pinhole camera is a camera without a lens
and with a single small aperture – effectively a light-proof box with a small
hole in one side. Light from a scene passes through this single point and
projects an inverted image on the opposite side of the box.
The human eye in bright light acts
similarly, as do cameras using small apertures.
Up to a certain point, the smaller the
hole, the sharper the image, but the dimmer the projected image. Optimally, the
size of the aperture should be 1/100 or less of the distance between it and the
projected image.
In Later stages, these discoveries led to the invention of the
camera obscura, and Ibn Al-Haytham built the first camera, a camera obscura or
pinhole camera, in history. He went on to explain that we see objects upright
and not upside-down, as the camera does, because of the connection of the optic
nerve with the brain, which analyses and defines the image.
During his practical experiments, Ibn
Al-Haytham often used the term al-Bayt al-Muthim, which was translated into
Latin as camera obscura, or dark, private or closed room or enclosed space.
Camera is still used today, as is qamara in Arabic which still means a private
or dark room.
Many of Ibn Al-Haytham’s works, especially
his huge Book of Optics, were translated into Latin by the medieval scholar
Gerard of Cremona. This has a profound impact on the 13th-century big thinkers
like Roger Bacon and Witelo, and even on the 15th-century works of Leonardo da
Vinci.
Today, the camera has gone from the humble
beginnings of Ibn-Al-Haytham’s dark front room, the qamara, to become a
sophisticated digital process, while the study of optics has blossomed into a
whole science covering lasers, optical sectioning of the human retina and
researching red bioluminescence in jelly fish.
