18 Questions
What is the primary function of the eyepieces or oculars in a stereomicroscope?
Magnifying the image captured by the objective lenses
What is the function of the focus block in a stereomicroscope?
Focusing the microscope for clear observation
What is the purpose of the luminous stand in a stereomicroscope setup?
Supporting the microscope and providing illumination
Which part of a stereomicroscope holds the eyepieces in place above the objective lens?
Eyepiece tube
What are the two primary optical systems found in a stereomicroscope?
Eyepiece Lenses and Objective Lenses
In a stereomicroscope, what do objective lenses primarily provide?
Fixed magnification
What is the primary purpose of the condenser lens in a transmission electron microscope (TEM)?
To illuminate the specimen with a uniform electron beam
What is the key difference between a thermionic gun and a field emission gun (FEG) in a TEM?
Thermionic guns use a tungsten or lanthanum hexaboride filament, while FEGs employ a thermally assisted cold field emitter or Schottky emitter
What is the role of the objective lens in a TEM?
To provide the formation of either the image or diffraction pattern of the specimen
How can the condenser lens in a TEM be used to control the electron beam?
The condenser lens can be used to defocus the electron beam above or below the specimen
What is the purpose of the aperture in a TEM?
To control the beam current and size of the illuminated area on the specimen
What is the purpose of the fluorescent screen in a TEM?
To allow the image to be viewed or recorded, either by an image plate or a CCD camera
In a transmission electron microscope (TEM), which component is responsible for generating the electron beam?
Electron gun
What is the primary function of the fluorescent screen in a TEM?
To convert the electron beam into a visible image
Which component in a TEM is responsible for focusing the electron beam onto the specimen?
Condenser lens
What is the primary advantage of using a TEM over a light microscope?
Higher resolution due to shorter wavelength of electrons
Which component in a TEM is responsible for magnifying the image?
Objective lens
What is the primary advantage of using a TEM over a scanning electron microscope (SEM)?
Ability to view thicker specimens
Test your knowledge on the basics of transmission electron microscopy, including specimen irradiation, electron beam, condenser lens system, and imaging techniques.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
