Ḥasan Ibn al-Haytham: The Father of Modern Optics

In this article we're excited to explore the life of the medieval genius who inspired our new lens, the Nour Triplet V 2.0/64 Bokeh Control Art Lens, Hasan Ibn al-Haytham.

Born in c. 965 to a family of Arabs in Basra, present day Iraq, Ḥasan Ibn al-Haytham grew up in a time of harmony and prosperity where the quest for knowledge was at its height; when schools and libraries flourished and society enjoyed great expansion in all subjects.

At the beginning of his career, Ḥasan Ibn al-Haytham held a position with the title vizier, acting as a minister in his city, where his notoriety to be knowledgeable in applied mathematics where known.

Religion being woven into society, he grew conflicted, frustrated he could see that theology wasn't going to be proved in any way. He then decided to dedicate his life to science completely.

Such an insightful and interrogative man, while focusing his studies on the principles of vision, he concluded that the beliefs held at that time were not convincing. Back then, through Euclid and Ptolemy, people believed that light travelled from our eyes to the objects, and this left Ibn al-Haytham unsatisfied. How could that be true when the stars in the sky were so far? Thanks to his inquisitiveness, he started decoding how our vision works.

Therefore, the seeker after the truth is not one who studies the writings of the ancients and, following his natural disposition, puts his trust in them, but rather the one who suspects his faith in them and questions what he gathers from them, the one who submits to argument and demonstration, and not to the sayings of a human being whose nature is fraught with all kinds of imperfection and deficiency. The duty of the man who investigates the writings of scientists, if learning the truth is his goal, is to make himself an enemy of all that he reads, and [...]attack it from every side. He should also suspect himself as he performs his critical examination of it, so that he may avoid falling into either prejudice or leniency." – Hasan Ibn al-Haytham

Life During The 10th Century

From the 8th century to the 13th century, the Fatimid Dynasty established a major caliphate that spanned much of the Middle East and North Africa. The Fatimids founded the city of al-Qāhirah (Cairo) "the Victorious" in 969 CE. as the new capital of their caliphate in Egypt.

As is often the case in cities' history, it was no more than a military base, and the family decided to establish their court outside the main settlement. It quickly evolved into a lavish palace with gardens, mosques, bath fountains, and madrassas (places of education.)

The vibrancy and richness of the time were palpable in Cairo, a cosmopolitan city with a progressive ruling, which provided a favorable thriving commercial hub located at the center of the trade road.

The city was a strategic port where anything could be found in its bazaars or on the streets. Lively souks offered a variety of goods from across the empire that expanded from China to India. Textiles, pottery, rugs, steel, soaps, pearls, and rubies – the alleys of the ancient city offered many rarities to its people.

The government heavily patronized scholars, and the best scholars had salaries estimated to be the equivalent of those of professional athletes today. It was during the rule of Al-Ḥākim bi-Amr, the sixth Fatimid caliph, known by his critics as the "Mad Caliph" – an eccentric ruler who issued several arbitrary edicts and laws, that Ibn al-Haytham moved to Cairo and claimed he could control the flow of the river Nile.

If I would be given the chance, I would implement a solution to regulate the Nile flooding. – Ibn al-Haytham

However, when he reached the banks of the great river he was aghast by the scale of the task and realized that it was impossible.

To avoid the potential deadly wrath of his temperamental and mentally unstable patron, he faked insanity. Stripped of his possessions he was kept under house arrest for about 10 years until Al-Hakim’s assassination in 1021.

Nevertheless, it was in these confined circumstances that Ibn al-Haytham produced some of the most pivotal work of his career. He went on to live a long and free life where he published 95 books, of which 50 still survive.

The Book Of Optics

The Book of Optics contained a diagram of the eye and its connection to the central nervous system, an observation never previously made. It is to Ibn al-Haytham that we owe the names for each part of the eye, and their English translations are still used today: retina, cornea, vitreous humor, and aqueous humor.

In his volumes he began to articulate and comprehend the principles of color theory by concluding that light is all the same whatever its source, and that it moves at variable speeds, what we nowadays know to be wavelengths.

His work on light behavior brought him to study mirror theory, light refraction, and how light passing through lenses breaks down into the color spectrum. It is of imperative importance in the field of optics to understand the Law of Refraction, which states that an incident ray of light traveling through a surface bends to an angle. The angle at the entrance is not the same as it is when it bends. When this law is understood it plays a crucial role in building optical lenses to guide the aberrations.

Such studies allowed for advancements in refining the shape of telescopes for astronomical studies. European scholars expanded on them and used his studies as a solid foundation for the development of lenses for telescopes, magnifying lenses, and eyeglasses.

It is difficult when we analyze his discoveries to determine which one is the most important, since they all changed human history. In a dark room within the palace walls, by chance a ray of light crossed the room and Ibn al-Haytham discovered the principles of the Camera Obscura. And we cannot underestimate the importance of the discovery that light travels in a straight line.

Modern photography is based on the revolutionary discoveries of light, optics, astronomy, mathematics, geometry and natural philosophy by Ibn al-Haytham. Without him our world would not be the same.

Discover more about our new Nour Triplet V 2.0/64 Bokeh Control Art Lens. Did you know the story of Ibn al-Haytham's life and work?

You can now find our Nour Triplet V 2.0/64 Bokeh Control Art Lens on Kickstarter.

written by eparrino on 2023-10-04 #culture #in-depth #light #geometry #optics #inventor #astronomy #mathematics #nour-triplet #ibn-al-haytham #the-book-of-optics #the-scientific-method #natural-philosophy