Phoenicians cooking on sand first discovered glass around 3500 BCE, but it took another 5,000 years or so before glass was shaped into a lens to create the first telescope. Hans Lippershey of Holland is often credited with the invention sometime in the 16th century. He almost certainly wasn't the first to make one, but he was the first to make the new device widely known.
The telescope was introduced to astronomy in 1609 by the great Italian scientist Galileo Galilei -- the first man to see the craters on the moon. He went on to discover sunspots, the four large moons of Jupiter and the rings of Saturn. His telescope was similar to opera glasses. It used an arrangement of glass lenses to magnify objects. This provided up to 30 times magnification and a narrow field of view, so Galileo could see no more than a quarter of the moon's face without repositioning his telescope.
Sir Isaac Newton's Design
Sir Isaac Newton introduced a new concept in telescope design in 1704. Instead of glass lenses, he used a curved mirror to gather light and reflect it back to a point of focus. This reflecting mirror acted like a light-collecting bucket -- the bigger the bucket, the more light it could collect.
Improvements to the First Designs
The Short telescope was created by Scottish optician and astronomer James Short in 1740. It was the first perfect parabolic, elliptic, distortionless mirror ideal for reflecting telescopes. James Short built over 1,360 telescopes.
The reflector telescope that Newton designed opened the door to magnifying objects millions of times, far beyond what could ever be achieved with a lens, but others tinkered with his invention over the years, trying to improve it.
Newton's fundamental principle of using a single curved mirror to gather in light remained the same, but ultimately, the size of the reflecting mirror was increased from the six-inch mirror used by Newton to a 6-meter mirror -- 236 inches in diameter. The mirror was provided by the Special Astrophysical Observatory in Russia, which opened in 1974.
The idea of using a segmented mirror dates back to the 19th century, but experiments with it were few and small. Many astronomers doubted its viability. The Keck Telescope finally pushed technology forward and brought this innovate design into reality.
The Introduction of Binoculars
The binocular is an optical instrument consisting of two similar telescopes, one for each eye, mounted on a single frame. When Hans Lippershey first applied for a patent on his instrument in 1608, he was actually asked to build a binocular version. He reportedly did so late that year.
Box-shaped binocular terrestrial telescopes were produced in the second half of the 17th century and the first half of the 18th century by Cherubin d'Orleans in Paris, Pietro Patroni in Milan and I.M. Dobler in Berlin. These were not successful because of their clumsy handling and poor quality.
Credit for the first real binocular telescope goes to J. P. Lemiere who devised one in 1825. The modern prism binocular began with Ignazio Porro's 1854 Italian patent for a prism erecting system.