Microscope Flashcards
What is a microscope?
An instrument that uses lenses and light to magnify objects too small to be seen by the naked eye.
What is a compound microscope?
A compound microscope uses a combination of lenses to help increase the magnification.
What is a bright-field microscope?
- Contains two magnifying pieces: eyepiece and the objective.
- Produces a dark object on an illuminated background or “bright field”.
How do you determine the total magnification of a compound/bright-field microscope?
Ocular magnification x Objective magnification.
E.g. If Ocular = 10x and Objective = 100x
Total Magnification = 10 x 100 = 1000X.
How should a microscope be carried?
Using the arm structure or if manufacture has provided a specific handle and then use 2nd hand to support at the base. Follow manufacturers instructions, I am sure this is just general. Note: Nikon video differed from class notes. I assume the reasons are the manufacturers design differences.
What does the microscope site on?
Base that is a firm horseshoe-foot shaped.
What is the stage?
Stage: A horizontal platform or shelf that the object being observed is placed.
What are the different illumination techniques (6)?
- Bright-field
- Phase contrast
- Polarizing
- Fluorescence
- Dark field
- Electron microscopy
Where is the light source directed through?
Light source is directed up through the condenser system.
Does the light bulb need to be positioned correctly and why?
Yes. It is important that the bulb be positioned correctly for proper alignment of the microscope.
What is the condenser and what does it do?
- Directs and focuses the beam of light from the bulb onto the material under examination.
- Conical lens system that is adjustable raised and lowered beneath the stage with an adjustable knob.
- It must be appropriately positioned to focus the light correctly on the slide and that the image field is evenly lighted.
Activity: Draw and label diagram on slide 5 of notes.
What is the field diaphragm and where is it located?
- The field diaphragm controls the area of the circle of light in the field of view when specimen and condenser have been properly focused.
- It is located in the light port in the base of the microscope which light passes up to the condenser.
What is an iris diaphragm? Where is it located?
Moveable aperture (opening) which adjusts the cone of light passing through the condenser into the objective in order to reduce glare. Uses a series of horizontally arranged interlocking plates with a central aperture.
Located at the bottom of the condenser but within the condenser body.
When would someone move the iris diaphragm out of the way?
Good question.
What is a one eyepiece and a two eyepiece microscope called?
- One eyepiece: Monocular microscope.
2. Two eyepieces: Binocular microscope.
