Microscope
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A 1915 Bausch and Lomb microscope
A microscope (Greek: μικρόν (micron) = small + σκοπεῖν (skopein) = to look at) is an instrument for viewing objects that are too small to be seen by the naked or unaided eye. Microscopes give us a larger (magnified) image of a tiny object. The microscopes we use in school and at home trace their history back almost four hundred years.
The most common type of microscope-and the first to be invented-is the optical microscope. This is an optical instrument containing one or more lenses that produce an enlarged image of an object placed in the focal plane of the lens(es). However, human creativity, employed in exploring nature, manifested in numerous improvements and new microscope designs, including the electron microscope, scanning probe microscope, field ion microscope, acoustic microscope, and so forth.
The science of investigating small objects using such an instrument is called microscopy, and the term microscopic means minute or very small, not easily visible with the unaided eye; in other words, requiring a microscope to examine. Microbiology is the scientific study of microorganisms, which are forms of life that are microscopic, such as bacteria, fungi, archaea, and protists.
Microscopes extending the range of human visual sensing reveal a world much grander than the world visible to the unaided eye and remind us of how much we cannot know by History
Robert Hooke's microscope (1665)-an engineered device used to study living systems
The first useful microscope is considered to have been developed in the Netherlands in the late sixteenth and early seventeenth century. There is almost as much confusion about the inventor as about the dates. Three different eyeglass makers have been given credit for the invention: Hans Lippershey (who also developed the first real telescope); Hans Janssen; and his son, Zacharias Janssen. Hans Janssen and Zacharias are often said to have invented the first compound microscope in 1590, but this was a declaration by Zacharias Janssen himself halfway through the seventeenth century. The date is certainly not likely, as it has been shown that Zacharias Janssen actually was born around 1590.
By 1609 Galileo Galilei is also credited with inventing a compound microscope with a convex and a concave lens, which he presented to Polish king Sigismund III in 1612.
In 1625 Giovanni Faber of Bamberg (1574-1629) coined the word microscope by analogy with telescope.
Lens quality in early microscopes was often poor so the images were not very clear. But even these rather crude microscopes were a great help in learning more about animals and plants. For example, in 1665, Robert Hooke (1635-1703) published Micrographia, a collection of biological micrographs developed using the compound microscope. Hooked coined the word cell for the structures he discovered in cork bark.
Thonius Philips van Leeuwenhoek, better known as Anton van Leeuwenhoek (1632-1723), was a Dutch tradesman who is well known for his contribution to the improvement of the microscope, as well as his contributions toward the establishment of microbiology. Known as "the father of microbiology," Leeuwenhoek, using his handcrafted microscopes, was the first to observe and describe single celled organisms that he first referred to as animalcules, and which we now refer to as microorganisms.
