Ibn Al-Haytham, a Muslim polymath and scientist, was born in 965 AD. He was born in the city of Basra in Iraq. At that time it was ruled by the Buyid Dynasty. He lived most of his life in Cairo, Egypt. Egypt was ruled by The Fatimid Caliphate. Ibn Al-Haytham thought he could control the Nile River every year. He proposed this idea to the Calipha at the time. Unfortunately he discovered that trying to control the Nile would not work. Fearing that he would be killed, he convinced everyone that he had gone mad. He was then put under house arrest.During this time, he continued to write texts and make discoveries until his death.
He was called by the Latin Al-Hazen or Al-Hacen. He was a polymath and studied many things. He made huge contributions to optics, physics, astronomy, mathematics, ophthalmology, philosophy, and visual perception.
He learned and explored many things throughout his studies. He studied much about light and how it moves. He also studied how it goes into the human eye. He was the one to build the first Camera Obscura (or the pinhole camera). He also wrote a long book called the Book of Optics. It was translated into Latin by a medieval scholar. He made many other contributions that help us nowadays make modern technology. This great man passed away in the year of 1040 AD in Cairo, Egypt. –By Abdul Rahman
Ibn Al-Haytham improved and still contributes to today’s technology. He invented the Camera Obscura and found a way to project light through the hole. His optics experiments have made many contributions to modern technology.
The Camera Obscura was a useful tool to learn with and see with. Ibn Al-Haytham said, “Light from an external scene passes through the hole and strikes a surface inside where it is reproduced, upside-down, but with color and perspective preserved. The image can be projected onto paper and can then be traced to produce a highly accurate representation.” He invented the first camera that lead to even more advanced versions.
Book of Optics
The Book of Optics is a book all about eyes and light. The Book of Optics is also called Kitab-al-Manzer. Ibn Al-Haytham’s book showed different lenses and how the lenses worked. He showed the way our eyes see. He talked about what is in our eye and what the eye is for. In his book he showed how to see a spectrum of light. His ideas were taken by many European scientists and said to be their ideas.
Astrophysics is the branch of astronomy that deals with the physics of the universe, including the physical properties of the celestial objects. Ibn Al-Haytham, in his Epitome of Astronomy, said that the heavenly bodies “Were accountable to the laws of physics.” Today there are different kinds of observational astrophysics such as:
Radio Astronomy: studies radiation with a wavelength more than a few millimeters i.e.: radio waves
Infrared Astronomy: studies with the wave length that is really long and invisible to the naked eye
Optical Astronomy: oldest kind of astronomy that is still used nowadays and uses the telescope
Ultraviolet, x-ray, and gamma ray Astronomy: study very energetic process- such as binary, pulsars, black holes, magentars etc. These different types of radiation do not penetrate the Earth’s atmosphere.
The Human Eye
One of Ibn Al-Haytham’s first “less important” studies was the way the eye moves. He found that movements of the eye are important to building up visuals of the world. He realized that perception is a big process and that reception of light by the eye is only the beginning.
Many scientists tried to do what Ibn Al-Haytham did, but unfortunately, all of them died trying to prove their knowledge and points of view. Other people similar to Ibn Al-Haytham played important roles in society also. For example, Helmholtz’s theory still impacts modern research in vision.
Another one of Ibn Al-Haytham’s studies states the importance of visual contrast. He realized that the colors of an object are impacted by the color of its surroundings. Which means that the contrasted brightness provides reasons to why we cannot see the stars during the day.
“This remarkable man deserves much further study,” said Charles Gross. In agreement with this statement, Ibn Al-Haytham needs a lot more attention and investigation of his work. Ibn Al-Haytham studies’ of vision led to many things such as the invention of the camera which is used every day.
The Digital Camera
Many of Ibn Al-Haytham’s discoveries influence modern technology like the digital camera. Legend has it that while under house arrest he stayed up all night making holes in the walls, and spent his days starring at shafts of light. These experiments under house arrest led him to an extraordinary discovery, the Camera Obscura. He also correctly explained the atmospheric refraction and the augmentation of the apparent diameter of the sun and moon when they are near the horizon. He established that rays of light start from the object to travel towards the eye, and not the reverse.
Ibn Al-Haytham’s work with Khalifa
The sixth Khalifa, Al-Hakim bi-amr Allah, gained power from his father who was also a Khalifa. He ruled for about 20 years. He is sometimes referred to as the mad caliph because of his weird and cruel acts.He used his power to rage against Christians in particular. He abused his power by doing harsh deeds. These acts are rare in during that era. His death was a mystery because one night he went to journey to the al-Muqattam hills outside of Cairo and never returned, when a search party was sent all they found was his donkey and his blood stained garments.
Once Al-Hakim the Khalifa called in ibn Al-Haytham to control the flooding of the Nile. Every year in the late summer, the Nile River would flood. When the river flooded, it would make the soil very fertile. This made the Nile Valley a very good place to farm but the flood level often changed. If the flood level were low it would cause drought and famine. If it were high it would wipe out all the crops. Since the flood level changed a lot, a lot of people wanted to control the flooding.
Al-Haytham assumed he could build a dam, but after some fieldwork he was convinced it was impossible because he was planning to build it with with mud and rocks. Fearing the Khalifas anger he faked his insanity and was put under house arrest until the Khalifa died, which was about 10 years later. During the house arrest he wrote the very influential Book of Optics.
The place where he was going to build the dam is the location of where the present-day Aswan Dam is. The Aswan Dam was built in 1902. It was designed by Sir William Willcocks. It can generate hydroelectricity. It is also used for water irrigation and to control floods.