Online lab microscope simulator

This is an onion cell at 40x magnification

History of the microscope

Zacharias Janssen is said to have the first to invent the microscope. Around 1595, Janssen amde the first compound microscope that was a simple tupe with lenses on both ends and it ranged from 3x to 9x.

Robert Hooke played an important role in the improvment of the compound microscope. This said " micrographia" was the study of the cell describing the features of the plant tissue seen under the microscope.

Leeuwenhoek made the best one lens microscope of his time. He was the first to describe bacteria from the teeth, protazoans from pond water, and helped proved the theory of blood circulation. He was a very talented man.

There are several types of microscopes:

Compound

Dissection

Scanning electron microscope SEM

Transmission electron microscope TEM

The compound microscope has a two dimensional image and is light illuminated. Having a high magnification and a low resolution it is still the most common used microscope.

The dissection microscope is also a light illuminated microscope. It has a low magnification which makes it good fordissection because you can see the big picture but it is n ot good for looking at cells.

SEM or scanning electron microscope, is one of the two electron illunmiating microscopes. The picture is in black and white and is seen in 3-D because of its high resolution and its high magnification. The specimen is covered in gold.

TEM or transmission electron microscope, is also electron illuminated. It has a high magnification and high resolution so it has a 2-D view.

Some of the parts of the microscope are the stage, focus knobs, iris, oculars, and objectives.

The stage is the flat platform that you place the slide on. It is easiest to adjust the stage by looking at the microscope.

Focus knobs are how you focus what you are looking at. These are best to use while you are looking at the microscope. They are located on the side of the microscope.

Iris is a rotating disc under the stage of the microscope. This has different size holes that adjust the size of the cone of the light that is projected upwards. This is easier to adjust while looking in the oculars.

Oculars are the lenses at the top that you look through.

Objectives usually consists of 3-4 lenses. They are what changes the power of the magnification. You can adjust by looking in the oculars or looking at the microscope

Looking at the stage from the outside and adjust the course adjustment knob until the body tube almost touches the slide. Look through the eyepeice and adjust the course adjustment knob very slowly until the specimen comes into focus. To change to the high power objective lense look at the microscope from the side and revolve the nosepiece carefully until high power objective lens clicks into place. Focus on the specimen by turning the fine adjustment knob.