Ch.2 Microscopy Flashcards
Microscope
instrument that magnifies an image, enabling very small objects to be observed
Resolution
- visual clarity
- the ability to distinguish between two objects
- the greater the resolution, the smaller the distance between two objects
Rheostat
adjusts light intensity
Base
- supportive bottom piece
- includes substage light
Substage light
provides light source
Head
- upper part which contains lenses and rotating nosepiece
- ocular lenses, nosepiece, objective lens
Ocular lenses
lenses used to observe microscope specimen
Nosepiece
rotates to change from one objective lens to another
Objective lens
- 4X (scanning)
- 10X (low power)
- 40X (high power)
- 100X (oil immersion)
Arm
- connects the head and base
- stage, coarse adjustment knobs, fine adjustment knobs, condenser, iris diaphragm
Stage
flat platform where the microscope slide is placed
Coarse adjustment knob
raises and lowers the stage in large increments moving it farther or closer from objective lens, controlling focus
Fine adjustment knob
used for precision focusing raising or lowering the stage in very small increments
Condensor
below the stage, control light intensity
Iris diaphragm
beneath condenser, regulates the amount of light passing through the condenser
Total magnification (TM)
determined by multiplying the ocular lens power and the objective lens power
Working distance
distance between the lens and slide
High power
- 40X
- 400X (TM)
- closest lens to slide
- smallest field of view
- largest image
Low power
- 10X
- 100X (TM)
- lens medium distance from slide
- intermediate size field of view
- intermediate size image
Scanning power
- 4X
- 40X (TM)
- lens farthest from slide
- largest field of view
- smallest image
Parfocal
once objectives are switched there is little to no refocusing required
Field of view
area of the slide that is visible to you looking though the microscope
Depth of field
vertical distance that is in focus
