LAB 1- MICROSCOPY Flashcards
4 major types of microscope
dissecting light ()
compound light (contains both concave ocular lens and convex objective lens)
scanning electron
transmission electron
Concave lens
impart real image
Convex lens
imparts inverted virtual image; image upside down and backwards
microscope parts
look at image
dissecting microscope
- concave ocular lens, concave objective lens
- fixed ocular objective (10x)
- specimens can be observed in three dimensions, advanatge of large working distance
compound microscope
- fixed 10X ocular lens
- 4 objective lens (scanning (4x), low-power (10x), high-power (40x), oil immersion(100x)
- always start on scanning power*
total magnification
magnification of objective lens x ocular lens
mag vs resolution
mag increases, reoslution decreases
resolution
ability to distinguish between two points clearly
improving resolution
use of light
high quality glass of slides
immersion oil
blue light filter ( blue has shorter wavelength so filter makes more photons hit specimen which offers better visual acuity
electron microscopy
specimen flooded with concentrated beam of electrons
tranmission vs scanning electron images
look at images
SEM: electrons beam scan over surface of samples, view external details
TEM: electron beams pass through thin sample, producing internal details
depth of focus
vertical distance that remians in focus at one time
shallow under highest powers
mag vs depth of focus
mag increases, depth of focus decreases
field of view
entire area you can see at one time
