Types of microscopes

Question 1

Stereoscopic microscope

Answer 1

10-125x range, large working distance
good depth of focus

Question 2

compound microscope

Answer 2

40-450x range
precision controls for focus and light intensity

Question 3

comparison microscope

Answer 3

allows side by side comparison

Question 4

fluorescence microscope

Answer 4

the illumination light is UV
allows samples to fluoresce so tagging can be used

Question 5

polarised light microscope

Answer 5

normal light can become polarised when passed through certain materials
good for anisotropic substances (same property = different values in different directions)

Question 6

bright field

Answer 6

light from lamp source illuminates sample but rays must be changed to achieve contrast to visualise
can be destructive if have to stain to visualise

Question 7

dark field

Answer 7

only collects reflected light, if no sample then no image. sample added = collects scattered light
provides contrast without staining

Question 8

snell’s law

Answer 8

determined by the RI difference between mounting medium and particle
for isotropic substances, can only determine refractive index

Question 9

Becke line test

Answer 9

measuring the RI between particle and mounting medium
small particles behave like lenses and refract light