The telescope was introduced to astronomy in 1609 by the great Italian scientist Galileo Galilei, who became the first man to see the craters of the moon, and who went on to discover sunspots, the four large moons of Jupiter, and the rings of Saturn. Galileo's telescope was similar to a pair of opera glasses in that it used an arrangement of glass lenses to magnify objects. This arrangement provided limited magnification--up to 30 times for Galileo--and a narrow field of view; Galileo could see no more than a quarter of the moon's face without repositioning his telescope.

In 1704, Sir Issac Newton announced a new concept in telescope design whereby instead of glass lenses, a curved mirror was used to gather in light and reflect it back to a point of focus. This reflecting mirror acts like a light-collecting bucket: the bigger the bucket, the more light it can collect. The reflector telescope that Newton designed opened the door to magnifying objects millions of times--far beyond what could ever be obtained with a lens.

Newton's fundamental principle of using a single curved mirror to gather in light remained the same. The major change that took place was the growth in the size of the reflecting mirror, from the 6-inch mirror used by Newton to the 6-meter (236 inches in diameter) mirror of the Special Astrophysical Observatory in Russia, which opened in 1974.

The idea of a segmented mirror dated back to the 19th century, but experiments with it had been few and small, and many astronomers doubted its viability. It remained for the Keck Telescope to push the technology forward and bring into reality this innovative design.

A binocular is a optical instrument for providing a magnified view of distant objects, consisting of two similar telescopes, one for each eye, mounted on a single frame. The first binocular telescope was invented by J. P. Lemiere in 1825.

The Early History of the Binocular
The modern prism binocular began with Ignatio Porro's 1854 Italian patent for a prism erecting system.

The First 300 Years of Binocular Telescopes
"What we call a binocular is a binocular telescope, two small prismatic telescopes joined together. When Hans Lippershey applied for a patent on his instrument in 1608, the bureaucracy in charge, who had never before seen a telescope, asked him to build a binocular version of it, with quartz optics, which he is reported to have completed in December 1608."

Telescopes and their Makers
"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, by Pattroni in Milan, and by I.M. Dobler in Berlin; but were not successful because of their clumsy handling and poor quality."

Telescope Facts - James Short
The Short Telescope, was made by the Scottish Instrument maker James Short in 1740. An optician and astronomer, James Short invented the first perfect parabolic and elliptic, distortionless mirror ideal for reflecting telescopes. James Short built over 1,360 telescopes.
James Short - Biography

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