Then
His optics corrected the old idea that the eye emits rays, and his books carried experimental thinking across the Islamic world to Europe.
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Ibn al-Haytham
c. 965 - 1040 · Islamic Golden Age (Basra / Cairo)
Ibn al-Haytham, known as Alhazen in Europe, transformed the study of light and sight and is often called one of the earliest scientists to rely on controlled experimentation.
- Physics
- Astronomy
- Islamic Golden Age
Lived
c. 965 - 1040
Era
Islamic Golden Age
Primary field
Physics
Signature idea
Pioneer of experimental optics and the scientific method
Their place in history
c. 965 - 1040
The question they asked
How does light travel, and how do we actually see objects?
The Contribution
What this scientist actually did — precisely and plainly.
In his “Book of Optics” he argued that vision happens when light reflected from objects enters the eye, and he described pinhole imaging and the camera obscura.
How the Work Advanced Knowledge
The tools, experiments and reasoning behind the discovery.
He combined geometry with repeatable experiments — controlling light sources, apertures and screens — to test his claims, a method far ahead of his time.
Why It Mattered Then / Today
From their own moment in history to the world we live in now.
Today
The camera obscura led to photography and cameras; his approach of hypothesis plus experiment became the backbone of the modern scientific method.
Important Works or Discoveries
Landmarks that carried the idea into the world.
- Kitab al-Manazir (Book of Optics)
- On the Configuration of the World
- Doubts Concerning Ptolemy
Sources
Where this profile was verified.
Last reviewed: 2026-09-22
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