1. MICROSCOPES Light (visible) Fluorescent U-V Electron Monocular
4/17/2017
MICROSCOPES
“illumination”
Light (visible)
Fluorescent
U-V
Electron
eyepieces
Monocular
Binocular
Resolving Power
N.A. affects
Wavelength affects
specimen background
Bright field
Dark field
MICROSCOPES
Microscopes

2. PARTS & TERMS Lenses (ocular, objective) Total Magnification Condenser
4/17/2017
PARTS & TERMS
Lenses (ocular, objective)
Total Magnification
ocular mag. X objective mag.
Condenser
Diaphram
MICROSCOPES
Microscopes

3. PARTS & TERMS Numerical Aperture (N.A.)
4/17/2017
PARTS & TERMS
Numerical Aperture (N.A.)
optical characteristic of a lens
N.A. = i sinq
N.A. increases with magnification
MICROSCOPES
Microscopes

4. [ RP of human eye ~ 0.2mm = ______m ]
4/17/2017
PARTS & TERMS
Resolving Power (R.P.)
size of the smallest discernable detail
minimum distance between objects so that they are able to be distinguished as separate
(l in nm)
R.P. = wavelength of illumination
(2)N.A.
MICROSCOPES
[ RP of human eye ~ 0.2mm = ______m ]
Microscopes

5. Resolving Power (R.P.) l = 650nm, NA = 0.25
4/17/2017
Resolving Power (R.P.)
l = 650nm, NA = 0.25
R.P. = l/2NA = _____nm = _____ m
l = 650nm, NA = 1.25
R.P. = l/2NA = _____nm = _____ m
l = 450nm, NA = 1.25
R.P. = l/2NA = _____nm = _____ m
MICROSCOPES
Microscopes

6. Larger or Smaller R.P. = BETTER ?
4/17/2017
Resolving Power (R.P.)
R.P. = l/2NA
Larger or Smaller R.P. = BETTER ?
R.P. improves as N.A. increases or decreases?
R.P. improves as l increases or decreases?
MICROSCOPES
Microscopes

7. 4/17/2017
Types of Scopes
MICROSCOPES
Microscopes

8. 4/17/2017
Types of Scopes
MICROSCOPES
Microscopes

9. Types of Scopes Compound Light Bright or Dark field
4/17/2017
Types of Scopes
Compound Light
Bright or Dark field
Use blue light or blue filter for shorter l
R.P. ~ 0.2m
MICROSCOPES
Microscopes

10. 4/17/2017
Microscopes

11. Types of Scopes Fluorescent Dark field compound light microscope
4/17/2017
Types of Scopes
Fluorescent
Dark field compound light microscope
Uses U-V for side illumination of specimen, fluorescent parts or dyes give off visible light that is viewed
R.P. ~ 0.2m
MICROSCOPES
Microscopes

12. Types of Scopes UltraViolet (U-V) Uses U-V as illumination (shorter l)
4/17/2017
Types of Scopes
UltraViolet (U-V)
Uses U-V as illumination (shorter l)
Image recorded then viewed… still or video camera image (should NOT look directly at U-V!)
Special lens material (quartz), glass absorbs U-V
R.P. ~ 0.15m
MICROSCOPES
Microscopes

13. Types of Scopes Electron Microscopes
4/17/2017
Types of Scopes
Electron Microscopes
Use electron beam for illumination, magnets for “lenses”, video to view
Transmission Electron Microscope (TEM)
beam passes thru, view internal structure
Scanning Electron Microscope (SEM)
beam reflects, see external structure, texture
MICROSCOPES
Microscopes

14. 4/17/2017
Microscopes

15. Types of Scopes Transmission Electron Microscope (TEM) MICROSCOPES
4/17/2017
Types of Scopes
Transmission Electron Microscope (TEM)
MICROSCOPES
Microscopes

16. Types of Scopes Transmission Electron Microscope (TEM)
4/17/2017
Types of Scopes
Transmission Electron Microscope (TEM)
Special specimen preparation (vacuum)
Working magnification:
whole bacteria….. 8,000x - 10,000x
thin section, viruses…. 30,000x - 40,000x
Maximum magnification ~100,000x
R.P. ~0.001m = ______nm
MICROSCOPES
Microscopes

17. 4/17/2017
rickettsia
herpes simplex
Microscopes

18. Types of Scopes Scanning Electron Microscope (SEM) MICROSCOPES
4/17/2017
Types of Scopes
Scanning Electron Microscope (SEM)
MICROSCOPES
Microscopes

19. Types of Scopes Scanning Electron Microscope (SEM)
4/17/2017
Types of Scopes
Scanning Electron Microscope (SEM)
Special specimen preparation (vacuum & conductor)
Working magnification:
14,000x - 50,000x
Maximum magnification ~130,000x
R.P. ~0.01m = ______nm
MICROSCOPES
Microscopes

20. 4/17/2017
Q fever
(rickettsia)
Image
enhancement
Microscopes