AS101 Lecture Notes - Lecture 1: Diffraction-Limited System, Light Pollution, Diffraction
Document Summary
When the surfaces are closer then use a thin lens. Focal plane where light from multiple directions come towards the focus. Image behind a convex lens actually upside down but our brain will flip the image. Refracting telescope will focus its light with the lens (galileo: will need to be long to optimize the distance between lenses, large lenses for light collection. Reflecting telescope focus on light with mirrors (newton: have a larger diameter, stuff built after 1900 are reflector telescopes. These lenses are chromatic aberrations and must always be corrected. Objective lenses are described to be heavy and are difficult to stabilize. Small telescopes use other focals which are tougher to use for larger telescopes. The lens shape and surface are extremely important. Light collecting area: larger area the more light it can collect in a small period of time. Angular resolution: larger can capture images with greater detail. Also known to some as resolving power.
