Why was the refracting telescope invented

Some reports claim that he heard of similar devices that were made by other people, while some believe that he simply came to idea to it when he saw children playing with his lenses.

In any case, in he managed to create first crude telescope that had either two convex lenses that produced inverted image or a convex objective and concave eyepiece lens that would produce upright image.

This design was brought to the States General of the Netherlands so that it could be patented, but there Lippershey encountered problems. Even though the managed to be quicker than one another lens maker Jacob Metius , Dutch government recognized that several other people have managed to create devices of very similar design that other spectacle makers wanted to take credit for. Lippershey was not awarded a patent, but he received generous reward by Dutch government. Keplerian telescope A Keplerian type refracting telescope.

A variation on the Galilean telescope was suggested by Johannes Kepler in his book Dioptrice. He noted that a telescopic device could be built using two convex lenses, but the image it produced would be upside down. T he advantage of this design, according to Kepler, was its larger field of view and high magnification. His recommendation was not immediately taken up by astronomers, however.

The Keplerian telescope was not accepted until Christoph Scheiner, a German Jesuit mathematician interested in instruments, published his book Rosa Ursina. Sunspot plate from Schneiner's Tres Epistolae. For his study of sunspots, Scheiner experimented with telescopes having only convex lenses. He found that when he viewed an object directly through such an instrument the image was flipped upside down.

But it was much brighter and the field of view much larger than in a Galilean telescope, as Kepler had predicted. Since for astronomical observations an inverted image is no problem, the advantages of what became known as the "astronomical telescope" led to its general acceptance in the science community by the middle of the 17 th century.

Hevelius and foot telescope. One disadvantage of the astronomical telescope suggested by Kepler and advocated by Scheiner was that its higher magnification was accompanied by more spherical and chromatic aberration - geometric distortion and false colors.

Over the next several decades, lens-grinding and polishing techniques improved gradually. A specialized craft community of telescope makers slowly developed. These craftsmen worked to produce better spherical lenses with decreased curvature and a longer focal length which improved the quality of telescopes but made them longer. In the sword of Orion are three stars quite close together.

In I chanced to be viewing the middle of one of these with a telescope, instead of a single star twelve showed themselves a not uncommon occurrence. Three of these almost touched each other, and with four others shone through the nebula, so that the space around them seemed far brighter than the rest of the heavens, which was entirely clear and appeared quite black, the effect being that of an opening in the sky through which a brighter region was visible.

An even larger "long-focus" telescope was described by the German astronomer Johannes Hevelius in his book Machinae Coelestis. He made telescopes with focal lengths as long as feet and lenses up to 8 inches in diameter. Their value as research tools was questionable, however, since the telescope's frame flexed and vibrated in the slightest breeze. Hevelius's rooftop observatory from book Machina Coelestis.

The Huygens brothers also developed "aerial telescopes. The astronomer raised and lowered this and found the image by trial and error. A compound eyepiece on a little stand was then positioned to receive the image cast by the objective. Although astronomers made some discoveries with these telescopes, their usefulness was limited - alignment on windy nights, for example, was difficult - and their design cumbersome.

By the beginning of the 18th century, very long refracting telescopes were rarely used any more. Others claimed at the time that he stole the design from another eyeglass maker, Zacharias Jansen.

Related: Best telescopes Top picks for viewing planets, stars, and more. Jansen and Lippershey lived in the same town and both worked on making optical instruments. Scholars generally argue, however, that there is no real evidence that Lippershey did not develop his telescope independently. Lippershey, therefore, gets the credit for the telescope, because of the patent application, while Jansen is credited with inventing the compound microscope.

Both appear to have contributed to the development of both instruments. Adding to the confusion, yet another Dutchman, Jacob Metius, applied for a patent for a telescope a few weeks after Lippershey. The government of the Netherlands turned down both applications because of the counterclaims.

Also, officials said the device was easy to reproduce, making it difficult to patent. In the end, Metius got a small reward, but the government paid Lippershey a handsome fee to make copies of his telescope. In , Galileo Galilei heard about the "Dutch perspective glasses" and within days had designed one of his own — without ever seeing one. He made some improvements — his creation could magnify objects 20 times — and presented his device to the Venetian Senate.

Galileo was the first to point a telescope skyward. He was able to make out mountains and craters on the moon, as well as a ribbon of diffuse light arching across the sky — the Milky Way. He also discovered the rings of Saturn , sunspots and four of Jupiter's moons.

Thomas Harriot, a British ethnographer and mathematician, also used a spyglass to observe the moon. Harriot became famous for his travels to the early settlements in Virginia to detail resources there.

His August drawings of the moon predate Galileo's, but were never published. The more Galileo looked, the more he was convinced of the sun-centered Copernican model of the planets.

But his ideas were considered heretical, and Galileo was called to appear before the inquisition in Rome in He struck a plea bargain and was sentenced to house arrest, where he continued to work and write until his death in Elsewhere in Europe, scientists began improving the telescope. Johannes Kepler studied the optics and designed a telescope with two convex lenses, which made the images appear upside down.