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The History Of The Microscope Essay Research

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The word microscope comes from two Greek words, micro meaning small and scope meaning to see. Microscope are instruments used to enhance our vision to see things that are to small to see with the naked eye. The first forms of microscopes were lenses used by an English scientist named Roger Bacon who wrote about using them to magnify things.

The first actual microscope was made and used by a Dutch naturalist named Anton van Leeuwenhoek that magnified about 200 times. In about 1674 he said that he had seen little animals. This invention of the microscope was also the invention of microbiology.

The microscope has come a long way since Bacon and Leeuwenhoek. There are many different types of microscopes the ones Bacon and Leewunwenhoek had were light microscopes that use lenses and light to see whatever they are trying to see. The first compound light microscope was made by Hans and Zacharias Janssen in 1590 this microscope had two separate lenses, but it was not very powerful. Since then many people have made improvements on the microscope, even our old friend from integrated science H the astronomer Johannes Kepler had a few thoughts on a better design. The light microscope is mainly used in the fields of biology and medicine.

Also since then new ideas for different microscopes have come along. In 1932 the phase-contrast microscope was invented by Frits Zernike to help biologist examine living material without having to stain which sometimes killed the material. In the 1800 s the first polarizing microscopes were developed to study crystals. Another microscope that is very useful, not that the others aren t, is the stereomicroscope that show things in three dimensions. These microscopes are used to study things like fleas that are too small for the eye but too large for medical microscopes.

The electron microscope is an amazing and exciting instrument that has helped further the science of physics as well as chemistry and biology, these microscopes are used in almost every field of science. Optical microscopes can magnify up to about 1,400 times, but the electron microscope can magnify at least to 1,000,000 times. The first electron microscopes were built in Germany by Max Knoll, Ernst Ruska, Ernst Bruche and H. Johnson in 1932.

The electron microscope has a few different variations. One of them is the transmission electron microscope that shoots beams of electrons through the specimen. the beams are focused by magnetic or electric lenses. The image appears on a fluorescent screen something like a television screen, and it can also be photographed. Those photographs can then be enlarged for a closer study.

The scanning electron microscope was developed in the 1970 s and built by Albert Crewe. The scanning electron microscope sweeps a beam of electrons back and forth over the specimen. Then it forms a picture of the surface that is very clear and appears three dimensional. This electron microscope can show single atoms of uranium and other heavy elements so that they can be identified and recognized.

The third, and last, electron microscope that I will mention is the ion emission microscope. This one was invented by Erwin Mueller in the 1950 s. It is used to study the arrangement of atoms in metals. The ion emission microscope does this by heating up a very fine tipped needle of the metal being studied. The needle is heated in a chamber of helium gas the helium atoms bounce off the tip of the needle onto a screen kind of like a television.

Beside the light and electron microscopes there are others like the X-ray and the acoustic microscopes. The X-ray microscope was first built by a pair of American scientist whose names are Paul Kirkpatrick and Albert Vinicio around 1948. This microscope allows details to be see that weren t imaginable before its creation. It passes x-rays through the object and produces a picture on a special type of film.

Acoustic microscopes, in the same fashion as the x-ray microscope, send sound waves through the object and are then made visible by a device that is called a transducer. This type of microscope was developed in the 1970 s.

The microscope has come a long way since the lenses of Roger Bacon or even the simple microscope of Leeuwenhoek. All microscopes have the same purpose, and that is to make the object of study more easy to see and study. From the light microscope to the acoustic there have been many improvements to fit the needs of the scientist using it and that, I believe, is the key to its success in the science world. I believe that as long as science progress and the human imagination survives the years to come there will always be room for improvement for the microscope. This is why the microscope has truly been a useful instrument. The microscope is definitely one of the most important tools of the science world ever.




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