Theory of Telescopes
- All telescopes work on the same principles. They
gather more light than a human can on their own and they
then focus the light and form a image. So the bigger the
gathering device whether it be a lens or mirror the more
light it gathers but the amount of useable light is
affected by the quality of the instrument.
Invention
- The first telescopes were refracting telescopes. Refractors use two lenses to magnify objects and as the name implies they bend the light that they gather. There is some debate about who first invented the refracting telescope as it seems to have been used in several places and because there were several designs that came out at almost the same time. However, credit is generally given to two opticians in the Netherlands who came up with the initial design in 1608.
Versions
- In 1609, Galileo Galilei invented an improved version
of the refracting telescope and was the first to use it
for astronomical purposes. Galileo's primary lens was
convex and his eyepiece was concave, thus producing a
image that was right side up. His version is commonly
called a Galilean telescope.
- In 1611, Johannes Kepler improved the telescope by changing the eyepiece to a convex lens which made the field of view wider and was easier on the eyes though the image was inverted. His version is known as the Keplerian telescope.
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Concept
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