Card Set Information
Heme Lab Parts of the Microscope
Eyepiece (ocular lens)
Carries filtered light from objective lens to ocular lens.
Coarse adjustment knob
Generally focuses specimen.
Fine adjustment knob
Preisely focuses specimen.
Holds objective lenses, adjustable.
Variable magnifying lenses.
*not on test*
Holds slides in place, adjusts location.
Connects magnifying lenses to base of microscope.
Location of specimen.
Holds slide/specimen in place, allows for slight rearragement of location.
Allow increase or decrease of light through condenser.
Concentrates light rays on specimen. (the cone)
*not on test*
Point of arm adjustment (bends).
Connects base to stage.
Foot of microscope.
Substage adjustment lever
Adjusts height of condenser.
Reflects light through condenser.
Low power objective lense
High power objective lense
Oil immersion objective lense
Storage of Microscope
1. Condenser down.
2. Clean off objectives with lens tissue.
3. Place 10x objective over stage opening.
4. Lower body tube with coarse adjustment knob (all the way down). Place cover over microscope.
Microscopes are constructed so that changing from a lower to higher magnification requires only an adjustment with the fine adjustment knob.
Always focus on 10x first before going on to 45x or 97x. Locate the area of the slide you wish to examine under low power.
Focusing a parfocal microscope
1. Place microscope 8-14 inches away from light source.
2. Raise condenser all the way up.
3. Adjust the iris diaphragm all the way open and adjust the mirror so the brightest possible light comes through the glass top of the condenser.
4. Lower condeser half a turn.
5. Place slide on stage.
6. Looking from the side, lower the 10x objective as close to the slide as possible without touching.
7. To focus, look into the eyepiece and turn coarse adjustment knob toward yourself slowly.
8. Bring into clear focus with the fine adjustment knob.
Measured in mm the distance between the slide and the objective lens when slide is in focus.
Low 10x = 16mm
High 45x = 4mm
Oil 97x = 1.8mm
*As NA increases, resolving power increases, depth of focus decreases.*
Low 10x = .25
High 45x = .66
Oil 97x = 1.25