Microscope

A Microscope

A microscope greatly increases the angular separation of nearby point sources. It uses two lenses, the objective and
the eyepiece. When the microscope is "focused", the rays exiting the eyepiece are parallel and the observing eye is relaxed.
Higher magnification is obtained by switching to an objective of shorter focal length. In this animation:
1.  The lens of the eye is exaggerated to catch the exiting rays.
2.  The object (source) is allowed to move but not the microscope. In reality, the microscope moves to focus.
3.  The "Lock" button locks the horizontal position of the object allowing vertical but not sideways motion. "Release" releases.
4.  The vertical displacement of the object is displayed continuously. The "locked" distance from the objective is also displayed.
Activities

Select Lo Mag. Focus by dragging the source horizontally. Lock the source. Drag it vertically and watch the angular displacement.

Select Hi Mag. Focus by dragging the source horizontally. Lock the source. Drag it vertically and watch the angular displacement.
Verify the following:
1. For the same vertical displacement of the source, higher magnification means greater angular displacement.
2. As the magnification increases, the source must move closer to the objective to stay in focus.

Credits
Authored by Kevork Spartalian, University of Vermont, based on Davidson College physlets.