Notes

A microscope is an instrument that makes an enlarged image of a small object, thus revealing details too small to be seen by the unaided eye. The most familiar kind of microscope is the optical microscope, which uses visible light focused through lenses.

What does “microscope” mean?
The word “microscope” comes from the Latin “microscopium,” which is derived from the Greek words “mikros,” meaning “small,” and “skopein,” meaning “to look at.

Who invented the microscope?
It is not definitively known who invented the microscope. However, the earliest microscopes seem to have been made by Dutch opticians Hans Janssen and his son Zacharias Janssen and by Dutch instrument maker Hans Lippershey (who also invented the telescope) about 1590.

There were different versions of microscopes invented by different scientists like the Hooke’s microscope invented by Robert Hooke, Leeuwenhoek microscope invented by Anton von Leeuwenhoek, Janssen compound microscope invented by Janssen brother. Each of them has tried to reduce the limitations of previous versions of microscopes.

What are microscope slides?
Microscope slides are small rectangles of transparent glass or plastic, on which a specimen can rest so it can be examined under a microscope.

1. Simple Microscope
A simple microscope is a type of microscope that uses a single lens for magnification. It uses a single convex lens of a small focal length for magnification. In general, its magnification is about 10X.
2. Compound Microscope
Compound Microscope is a type of microscope that used visible light for illumination and multiple lenses system for magnification of specimen. Generally, it consists of two lenses; objective lens and ocular lens. It can magnify images up to 1000X. 6. Dark Field Microscope
Dark Field Microscope is a type of light microscope that uses only the light scattered by the specimen for producing a bright image with a darkfield around the specimen.
3. Phase Contrast Microscope
Phase Contrast Microscope is an optical microscope that converts small phase shifts in light into differences in light intensity developing more contrast in images that can be easily detected by human eyes
4. Fluorescence Microscope
Fluorescence Microscope is an optical microscope that uses fluorescence or phosphorescence to generate an enlarged image of a specimen.
. Electron Microscope
Electron Microscope is a microscope that uses accelerated electron, beams instead of light rays, to illuminate the specimen and get the highly magnified image.
6. Dark Field Microscope
Dark Field Microscope is a type of light microscope that uses only the light scattered by the specimen for producing a bright image with a darkfield around the specimen.
7. Dissecting Microscope (Stereo Microscope)
Dissecting Microscope or Stereo Microscope is a type of light microscope that uses lights reflected from the surface of a specimen to produce an image of low magnification.
8. Digital Microscope
Digital Microscope is a type of microscope that lack an ocular lens and instead contains a digital camera and screen to display image digitally.
9. Scanning Probe Microscope (SPM)
Scanning Probe Microscope (SPM) is a type of microscope that uses a scanning probe to scan the surface of the specimen and record the interaction to develop an image.
10. Inverted Microscope
Inverted Microscope is a type of light microscope whose objective lenses and turret are below the stage, and the illuminator and condenser are above the stage.
11. Acoustic Microscope
Acoustic Microscope is a type of microscope that uses a very high-frequency ultrasound wave instead of light or electrons to develop an enlarged image of an object
2. X-Ray Microscope
X-Ray Microscope is a type of optical microscope that uses an X-rays beam to illuminate samples and produce their enlarged image.
3. Polarizing Microscope
Polarizing Microscope is a special type of light microscope that uses polarized light to illuminate a specimen and develop its magnified image
14. Metallurgical Microscope
Metallurgical Microscope is a type of microscope that uses reflected light for observing metals to study their structure and organization
15. Pocket Microscope
Pocket Microscope is a small portable microscope designed to carry easily. It is a simple microscope containing an eyepiece, LED as light source and battery for LED operation, a mirror, and a stage for sample holding
16. USB Microscope
USB Microscope is a type of low-power digital microscope that is connected to the computer USB port. This type of microscope is used for observing insects, coins, gems, jewelry, small letters, scripts, crystals, etc. It is used in medical examination, endoscopy, and ENT examinations.
They are cheap and portable but have low magnification.

What is the resolution of a microscope?
Resolution is expressed in linear units, usually micrometres (μm)