In the late 19th century, physicists began to understand that light is an electromagnetic wave. This understanding led to the development of optics—the study of how light behaves. Optical physics is the branch of physics that studies the behavior of light and its interactions with matter.
Optical physics encompasses a wide range of topics, from the behavior of lasers and other optical devices to the nature of astronomical objects such as black holes. Researchers in optical physics use a variety of tools, including telescopes, microscopes, and computers. In addition to studying light itself, they also use light to probe other areas of physics, such as quantum mechanics and nuclear physics.
The history of optical physics is closely intertwined with the history of optics—the study of how light behaves. The word “optics” comes from the Greek word optikos, which means “related to vision.” The early Greeks believed that vision was caused by rays emanating from the eyes. This belief was supported by experiments conducted by Arabic scientists in the Middle Ages who used concave mirrors to focus sunlight into a beam that could set fire to distant objects.
The first scientific treatise on optics was written by Ibn al-Haytham, an Arab scientist who lived in present-day Iraq during the 11th century. His book Kitab al-Manazir (Book of Optics) described how lenses work and proposed that vision occurs when light reflects off an object and enters the eye. He also conducted experiments with mirrors and lenses, demonstrating that curved surfaces can cause light to bend (refract).
Ibn al-Haytham’s work laid the foundation for later advances in optics, including those made by Italian scientist Leonardo da Vinci (1452–1519). Da Vinci was fascinated by Ibn al-Haytham’s work and built on it to develop his own theories about vision and Light reflection off curved surfaces.. In 1543, German astronomer Johannes Kepler (1571–1630) published his seminal work Astronomia nova (New Astronomy), which included his laws of planetary motion—three mathematical relationships describing how planets move around stars