SESSION 1-MICROSCOPES.pptx

SESSION 1-MICROSCOPES WHAT IS A MICROSCOPE Microscope is a tool that produces enlarged images of small objects, allowing the observer to have an exceedingly close view of minute structures in a slide. It is primarily used for examination and analysis.  FUNCTIONS OF A MICROSCOPE The primary func...

SESSION 1-MICROSCOPES WHAT IS A MICROSCOPE Microscope is a tool that produces enlarged images of small objects, allowing the observer to have an exceedingly close view of minute structures in a slide. It is primarily used for examination and analysis.  FUNCTIONS OF A MICROSCOPE The primary function of a microscope is to study biological specimens. A microscope solely functions on two concepts – magnification and resolution. Magnification is simply the ability of the microscope to enlarge the image. Whereas the ability to analyze minute details depends on the resolution.  TYPES OF MICROSCOPE Light Microscopes These are basic microscopes that use light to magnify objects. The lenses in these microscopes refract the light for the objects beneath them to appear closer. The different types of light or optical microscopes are: Compound microscope Simple microscope Dissection or stereo microscope  TYPES OF MICROSCOPE Electron Microscopes Instead of light, these microscopes use beams of electrons to generate images. The two well- known electron microscopes are: TEM (Transmission Electron Microscope) – the electrons transmit or pass through a very thin specimen. SEM (Scanning Electron Microscope) – It scans through the surface of the specimen by focusing the electron beam.  COMPOUND MICROSCOPE Functions of compound microscope It simplifies the study of viruses and bacteria. They are used in pathology labs to make an easy diagnosis of diseases. They are also used in forensic laboratories to identify human fingerprints. Both simple and compound microscopes can be used for microbiological studies. Specimens like fungi and algae can be viewed under these microscopes. Microscopes can also be used to study soil particles.  DISSECTION MICROSCOPE Functions of dissection microscope Help to study the topography of solid samples. It is used for dissections and microsurgical procedures It is also used in forensic engineering  ELECTRON MICROSCOPE Functions of electron microscope Electron microscopes are expensive devices that are mostly used in industrial and medical research. They are used for micro characterization of a sample Helps in tissue imaging Device testing Mineral liberation analysis PARTS OF A COMPOUND OR SIMPLE MICROSCOPE  The ocular or eyepiece is what an observer looks through and is present in the upper portion of the microscope.  The eyepiece tube clasps the eyepieces which are positioned above the objective lens.  The objective lenses are the main optical lenses. They range in various magnifications from 4x to 100x and generally include 3 to 5 lenses on a single microscope.  Nosepiece houses the objective lenses. PARTS OF A COMPOUND OR SIMPLE MICROSCOPE  The fine and coarse focus knobs are the adjustment knobs that are often used to focus the microscope. They are coaxial knobs. This means the focusing system of both fine and coarse focus are mounted on the same axis. There is also a condenser focus knob which moves the condenser up or down to control the lighting  The stage is where the specimen to be viewed is placed. A mechanical stage is often used when working on a specimen at a higher magnification. This is when delicate movement of the specimen is required.  Stage clips are operated to hold the slide in place. To see different areas of the specimen, the observer must physically move the slide. A separate knob is present to move the slide in the mechanical stage. PARTS OF A COMPOUND OR SIMPLE MICROSCOPE  The aperture is a tiny hole in the stage via which the transmitted light enters the stage.  An illuminator acts as the light source and is typically located at the microscope’s base. Most light microscopes operate on halogen bulbs with low voltage and also have variable and continuous lighting control within the base.  Condenser is typically used to gather and focus the illuminator’s light onto the specimen. It is found beneath the stage and is often observed in conjunction with a diaphragm or iris.  Iris or Diaphragm regulates the amount of light that reaches the specimen. It is situated above the condenser but beneath the stage.