which has many lenses are called as compound microscope . The microscope transmits visible light from sources to eye or camera through sample. . .
Bright field Microscope Bright field microscope is the routinely used microscope in studying various aspects of cells. It allows light to pass directly through specimen and shows a well distinguished image from different portions of the specimen. The contrast can be increased by staining the specimen with reagent that reacts with cells and tissue components of the object. The light rays are focused by condenser on to the specimen on a microslide placed upon the adjustable platform called stage .
Light comes from the Compact Flourescent Lamp (CFL) or Light Emitting Diode (LED). Then it passes through two lens systems namely objective lens (closer to the object) and the eye piece (closer to eye). There are four objective lenses (5X, 10X, 45X and 100X) which can be rotated and fixed at certain point to get required magnification. It works on the principle of numerical aperture value and its own resolving power.
The first magnification of the microscope is done by the objective lens which is called primary magnification and it is real, inverted image. The second Resolution: The term resolving power or resolution refers to the ability of lenses to show the details of object lying between two points. It is the finest detail available from an object. It can be calculated using the following formula.
Resolution = .61λ NA Where, λ= wavelength of the light and NA is the numerical aperture. Numerical Aperture: It is an important optical constant associated with the optical lens denoting the ability to resolve. Higher the NA value greater will be the resolving power of the microscope. Magnification: The optical increase in size of an image is called magnification.
It is calculated by the following formula Magnification = size of image seen with the microscope size of the image seen with normal eye mycoplasma, cellular organelles, etc (Figure . a and b). . Scanning Electron Microscope: This is used to obtain three dimensional image