Telescope

• Telescope: device enables one to see distant objects. Has basic types; refracting and reflecting.
• Refracting Telescope: 1st type. Inverted. Has lenses as its objective and eyepiece
• Refracting: Accidentally invented by German-Dutch lens maker Hans Lippershey IN 1608.
• When Lippershey looked at a distant church using 2 converging lenses. He called this looker.
• Lippershey applied for a patent but he was denied because his invention was too simple that everyone knew it.
• Galileo made his own version, he called it Far Looker, using converging lens for the objective and diverging lens for the eyepiece
• Galileo Galilei: first one to use telescope to study celestial objects
• A refracting telescope works in the same way as the compound microscope.
• The first image formed is very near to the principal focus of the objective. It is real, inverted, and smaller than the object
• The eyepiece acts like a magnifying glass to produce the final virtual image at infinity.
• The distance between the two lenses is the length of telescope and is equal to the sum of focal lengths of the to lenses.
• Isaac Newton invented reflecting telescopes in 1668. A concave mirror is used as objectives instead of converge