A microscope (from the Greek: , mikrs, "small" and , skopen, "to look" or "see") is an instrument to see objects too small for the naked eye. The science of investigating small objects using such an instrument is called microscopy. Microscopic means invisible to the eye unless aided by a microscope. Microscopes are mechanical devices used for viewing objects and materials so minute in size that they are undetectable by the naked eye. The process conducted with such an instrument, called Microscopy, uses the combined schools of optical science and light reflection, controlled and manipulated through lenses, to study small objects at close range.

Parts of Microscope

Eyepiece Lens: the lens at the top that you look through. They are usually 10X or 15X power.Tube: Connects the eyepiece to the objective lensesArm: Supports the tube and connects it to the baseBase: The bottom of the microscope, used for supportIlluminator: A steady light source (110 volts) used in place of a mirror. If your microscope has a mirror, it is used to reflect light from an external light source up through the bottom of the stage.Stage: The flat platform where you place your slides. Stage clips hold the slides in place. If your microscope has a mechanical stage, you will be able to move the slide around by turning two knobs. One moves it left and right, the other moves it up and down.Revolving Nosepiece or Turret: This is the part that holds two or more objective lenses and can be rotated to easily change power.Objective Lenses: Usually you will find 3 or 4 objective lenses on a microscope. They almost always consist of 4X, 10X, 40X and 100X powers. When coupled with a 10X (most common) eyepiece lens, we get total magnifications of 40X (4X times 10X), 100X , 400X and 1000X. To have good resolution at 1000X, you will need a relatively sophisticated microscope with an Abbe condenser. The shortest lens is the lowest power, the longest one is the lens with the greatest power. Lenses are color coded and if built to DIN standards are interchangeable between microscopes. Rack Stop: This is an adjustment that determines how close the objective lens can get to the slide. It is set at the factory and keeps students from cranking the high power objective lens down into the slide and breaking things. You would only need to adjust this if you were using very thin slides and you weren't able to focus on the specimen at high power. Condenser Lens: The purpose of the condenser lens is to focus the light onto the specimen. Condenser lenses are most useful at the highest powers (400X and above). Microscopes with in stage condenser lenses render a sharper image than those with no lens (at 400X). Diaphragm or Iris: Many microscopes have a rotating disk under the stage. This diaphragm has different sized holes and is used to vary the intensity and size of the cone of light that is projected upward into the slide. There is no set rule regarding which setting to use for a particular power. Rather, the setting is a function of the transparency of the specimen, the degree of contrast you desire and the particular objective lens in use.

Different Kinds of Microscopes & Their UsesI want to do this! What's This? The microscope is an instrument used to magnify small objects. It has led to important biological discoveries and has undergone many innovations and improvements. There are a variety of microscopes including the compound microscope, dissecting microscope, Scanning Election Microscope and Transmission Electron Microscope.Compound Microscope1. Compound microscopes can be found in most biology and science classrooms. They are electrically operated and use light to enhance the image of a cell. They will have multiple lenses for viewing. Dissecting Microscope2. Dissecting microscopes are also known as stereo microscopes. They have low magnification and are also light powered. These microscopes can view objects larger than what a compound microscope is able to handle, in three dimensions. SEM3. A Scanning Electron Microscope uses electrons instead of light to create an image. These microscopes produce three-dimensional images with high resolution and magnification. They also have a larger depth of focus. TEM4. Transmission Electron Microscopes use electrons instead of light to create an image. The material prepared must be very thin. The beams of electrons that pass through it give the viewer high magnification and resolution. These give two-dimensional images.

Optical Microscope5. .Also a common type of microscope, the optical microscope uses light to illuminate the specimen for the observer by way of refractive lenses and glass eyepieces. Fluorescent microscopes work by the same principle but use a different wavelength of light. Simple Optical Microscope6. Uses one lens, the convex lens, in the magnifying process. This kind of microscope was used by Anton Van Leeuwenhoek during the late-sixteen and early-seventeenth centuries, around the time that the microscope was invented. Compound Optical Microscope7. Has two lenses, one for the eyepiece to serve the ocular perspective and one of short focal length for objective perspective. Multiple lenses work to minimize both chromatic and spherical aberrations so that the view is unobstructed and uncorruptedDigital Microscope 8. A digital microscope is composed of a microscope, a video camera and a screen for viewing. Eyepieces don't come into play as the image can be put on a video screen. Electron Microscope 9. Instead of light, electron microscopes use electrons to make the specimen visible by way of electrostatic and electromagnetic lenses. The electron microscope is among the most powerful types of microscopes, with scanning electron microscopes producing 3-D images and transmission electron microscopes producing 2-D images. Stereo Microscope 10. Also known as a dissection microscope, the stereo microscope has two objectives to capture light and create a three-dimensional effect for the observer.

Inverted Microscope 11. This kind of microscope views objects from an inverted position than that of regular microscopes. The inverted microscope specializes in the study of cell cultures in liquid.

Petro graphic Microscope 12. This kind of microscope features a polarizing filter, a rotating stage, and gypsum plate. Petro graphic Microscopes specialize in the study of inorganic substances whose properties tend to alter through shifting perspective.

Pocket Microscope 13. This kind of microscope consists of a single shaft with an eye piece at one end and an adjustable objective lens at the other. This old-style microscope has a case for easy carry.

Scanning Probe Microscope 14. This kind of microscope measures interaction between a physical probe and a sample to form a micrograph. Only surface data can be collected and analyzed from the sample. Types of Scanning Probe Microscopes include the Atomic Force Microscope, the Scanning Tunneling Microscope, the Electric Force Microscope, and the Magnetic Force Microscope.

Project In Science

Sub. by: Sub. to:Jayvee Leo Cabello Ms. Gladyann Castaneda

Microscope