c. 750 BCE The Nimrud lens shows early polished optics A rock-crystal object from Assyria is often cited as evidence of early lens-like manufacture. c. 500 BCE Greek thinkers theorize vision Classical philosophers begin systematic debates over how sight works, laying foundations for optics. c. 500 BCE Ptolemy studies reflection and refraction Hellenistic and Roman science develops geometric accounts of light behavior. 1021 Ibn al-Haytham completes the Book of Optics A major synthesis of experimental and mathematical optics transforms the study of vision and lenses. c. 500 BCE Reading stones help magnify text Simple convex lenses aid readers before framed spectacles become common. c. 1286 Spectacles emerge in Italy The first wearable eyeglasses appear in late medieval Italy, changing literacy and work. 1451 Nicholas of Cusa describes lenses for myopia Optical correction becomes more specialized as lens use expands. 1608 The telescope is patented in the Dutch Republic Refracting telescope designs reach practical form and spread quickly across Europe. 1609 Galileo turns the telescope to the sky Astronomical observation with improved telescopes reshapes Europe's understanding of the heavens. 1625 Compound microscope enters scientific use Magnifying lenses at very short focal lengths open new microscopic worlds. 1668 Newton builds a reflecting telescope Mirror-based design reduces chromatic aberration and expands optical instrument design. 1733 Achromatic lens concept reduces color fringing Combining different kinds of glass becomes a major advance in practical optics. 1826 Photography fixes optical images chemically Lenses become central not only to seeing but to recording and reproducing reality. 1840 Mass-produced spectacles broaden access Industrial manufacture lowers the cost of corrective lenses for everyday use. 1887 Zeiss systematizes modern optical production Precision industrial optics help standardize microscopes, cameras, and scientific instruments. 1929 Television makes optical-electronic imaging common Lens systems now serve mass media as well as science and vision correction. 1959 Fiber optics are proposed for communications Optics begins shifting from image-forming lenses toward guided light in telecommunications. 1960 The laser opens a new optical era Coherent light sources revolutionize measurement, medicine, storage, and communications. 1970 Low-loss optical fiber makes long-distance networks practical Breakthrough fiber improves the feasibility of using light to carry information over great distances. c. 2000 Phone cameras turn lenses into everyday infrastructure Billions of mobile devices make miniature optics a routine part of daily communication.