Microscope Lab

Zacharias Janssen was the first to invent the microscope in 1595 in Middleburg, Holland. Zacharias was a child at the time, so it is believed that his father may have made the first microscope rather than he. The Jansen's first microscope was a tube with lenses at each end. The magnification of these early scopes ranged from 3X to 9X, depending on the size of the diaphragm openings.

In 1670 Antonio Van Leevwenhoek discovered the single cell organisms which he called the "animalcules." His microscopes had a simple convex lens with 1/4'' focus magnification ranges from 50x -275x.

In 1750 the real beginnings of the scientific microscope began with F. Watkins cuff design microscope. The course focus was achieved by moving the body up and down and the fine focus was achieved with a micrometer. Today microscopes are much more advanced but these pioneers made all of it possible.

The stage of the microscope is the flat platform piece where you place slides by use the the stage clips. This is best adjusted by looking through the microscope.

The Focus Knobs on the microscope are used for fine and course focusing. Both focus knobs are located on the arm of the microscope. The course knob uses a low power to make images sharp, while the fine focus knob is used to make minor adjustments. These knobs are adjusted looking through the microscope.

Iris or Diaphragm is a rotating disk under the stage. It has different sized holes to adjust the intensity of the light. This is adjusted looking through the microscope.

Oculars are the eye piece lens you look through. They are usually 10x - 15x power.

Objective Lenses -There are usually 3 - 4 objective lenses on a microscope, each ranging from 4x, 10x, 40x, and 100x powers. They are color coded and usually interchangeable. These are best adjusted looking at them and not through them.