Euclid's Optics: geometry of the visual cone
Óptica de Euclides: geometría del cono visual
- Date
- c. 300 BCE · confidence medium
- Place
- Alexandria, Egypt
- Credited to
- Euclid
- Field
- Communication
⚠️ Disputed: the sources disagree.
What was discovered
An axiomatic treatise that assumes straight visual rays forming a cone from the eye and geometrically deduces the apparent size and position of objects. It is the earliest surviving geometrical optics and a basis of perspective.
Euclid's authorship of the Optics is accepted, but the transmitted form (Theon of Alexandria's recension) is debated, and the Catoptrics is probably by another author. The visual-ray (extramission) approach is not the modern theory.
What it led to
- the geometrical optics of Ptolemy, Alhazen and Kepler
- the mathematical theory of Renaissance perspective
- study of apparent size and vision in astronomy