Major Components of the Light Microscope

Light Microscopes are essential tools in biomedical research. The optical components allow much greater image resolution than viewing with the naked eye. By combining microscopy with digital image processing, researchers can enhance the visibility of the image and make precise quantitative measurements.

This video will guide you through the microscope's, main components, And their functions. Hello, I'm Victoria Sanon Frolic from the Core Optical Imaging Facility at the University of Texas Health Science Center in San Antonio. Today I will show you the major components of your life microscope and their basic functions.

So let's take a tour of your microscope. Before using a microscope, it is best to become familiar with its components and their functions. This is a Nikon eclipse TI inverted compound light microscope equipped for both transmitted light and epi fluorescent microscopy.

The direction along the axis of the microscope will be referred to as the Z axis and the perpendicular directions as the X and the Y axi. First, we will examine the eyepiece body tube, the nose piece containing the objectives and the stage. These are the main image forming components of the microscope.

The pieces are the interface between observer and microscope. By grasping the basis of the binocular eyepiece tubes, you can adjust the inter pupilary distance by moving them closer together or farther apart. This allows you to view comfortably with both eyes.

Simultaneously, the eyepiece focus may also now be adjusted for each eye independently. The magnification of the eyepiece is marked on the barrel. Cameras are routinely mounted onto microscopes for image acquisition.

This particular scope uses a C mount adapter to attach a CCD camera to the side port of the microscope body. A knob on the microscope is turned to position a prism in order to direct the image forming light rays away from the eye pieces and towards the camera, which is mounted on the camera port. The different objectives, which dictate most of the magnification and resolution are mounted on a rotating nose piece.

Each objective is marked with specifications such as the magnification, numerical aperture, the immersion medium required such as oil glycerin or air cover slip thickness, and other special features such as the illumination mode, the light leaving the eyepiece and nose pieces unfocused or projected to infinity. The body tube contains a positive focusing lens that brings the imaging light into focus for the eyepiece or camera. Now that I've shown you the image forming components of the scope, let's have a look at the components that will help us focus on an image and make adjustments to the Transmitted light.

Next, We will examine the specimen stage, which is the mechanical carrier that holds the specimen slide. By turning the knobs, you can adjust the specimens in the x and y directions. In the inverted microscope configuration, the stage is fixed and the specimen is focused by moving the objectives up and down along the Z AEs using course and fine focus knobs on the microscope body.

Now we will examine the transillumination components of the light microscope, which provide the light for visualizing your specimens. First, we have the lamp and housing, which provides the light for illuminating the specimen For light microscopy, the lamp is typically a low voltage halogen bulb with a tungsten filament with can be adjusted to control light intensity. A shutter may be placed after the light source to control the duration of illumination.

Just after the light source is a field diaphragm adjustment of the field, diaphragm controls the area or field of the specimen to be illuminated. Next is the component known as the condenser, whose main function is to focus bright uniform illumination to the specimen. The condenser or iris diaphragm located on the bottom of the condenser controls the angle of the condenser cone of illumination of the specimen.

Adjustment of this diaphragm controls the size and numerical aperture of the light cone directed towards the specimen, resulting in correct illumination, contrast, and depth of field optical adjustment of the condenser diaphragm results in proper filling of the front lens element of the objective lens. Ideally, this adjustment should be made for each objective in order to realize the full potential of the lens. For epi fluorescent illumination, the light source is typically a xenon or mercury arc lamp.

On our scope, we have a mercury based light source arc lamp should be handled with care as they may blow up. If mishandled. Be sure to wear gloves when installing the bulb because fingerprints and debris may create hot points and cause the lamp to crack, it is highly recommended not to run an arc lamp longer than the number of hours for which it is rated.

The fluorescent light path includes a field diaphragm and an aperture diaphragm. Similar to the transmission light pathway. Beyond these diaphragms, the light will encounter a set of filters which select light bandwidth and direct the illumination into the objective to reach the specimen in the epi illumination pathway, the objective acts As both the condenser and the objective.

We've just shown you the major components of your light microscope. I started off by showing you the image forming components of the microscope, namely the eye pieces, the objective, and the CCD camera. Then we reviewed the stage manipulation, the focus adjustment knobs, and the condenser.

So that's it. Thanks for watching and good luck With your microscopy.