Joseph von Fraunhofer, German optician, physicist, and astronomer (born 1787)

Joseph Ritter von Fraunhofer was a German physicist and optical lens manufacturer. He made optical glass, an achromatic telescope, and objective lenses. He developed diffraction grating and also invented the spectroscope. In 1814, he discovered and studied the dark absorption lines in the spectrum of the sun now known as Fraunhofer lines.