BINOCULAR MICROSCOPE: 

ITS FEATURES AND CARE 

©David B. Fankhauser, Ph.D.,
Professor of Biology and Chemistry
University of Cincinnati Clermont College,
Batavia OH 45103
 Left side view of a
binocular microscope
This page has been accessed Counter times since 11 October 2001. 
24 June 1987, latest rvsn 2 Jan 96, 23 Sept 96, 16 Dec 96, 7 July 97, 17 Sept 97, 30 June 98, 7 July 00, 25 June 01
Right side view of a 
binocular microscope

CARDINAL RULES FOR MICROSCOPE USE:

  1. To carry a microscope: grasp the arm firmly, lift and support under the base with other hand, set on a cleared desk. Remove and store its dust cover in cabinet under desk. Unwrap power cord, loop around gas outlet at rear of desk, plug into electrical outlet in front of desk.
  2. Clean the lenses: use ONLY lens paper. Polish the objectives and oculars: breathe on them lightly for moisture. (Polish slides with Kimwipes.) If the view is still foggy, ask for help.
  3. Always begin slide set-up with the stage lowered and the lowest power objective (4x) in place.
  4. Focus initially only by LOWERING the stage to the focal point using the coarse focus. NEVER raise the stage using the coarse focus during focusing.  (The objective may ram the slide which can damage both.)
  5. Use only the fine focus with higher power objectives. Make only minor changes in focus when necessary with the fine focus knob. If you totally lose focus, return to a lower objective to find the focal point. Do not use the 100x objective unless you have received specific instructions on its use. (See a separate handout for oil immersion procedure.)
  6. Carefully follow microscope use instructions. (See Using and Evaluating the Microscope.)
LEARN AND ILLUSTRATE THE FEATURES OF THE MICROSCOPE:
  1. Using proper carrying technique (see rule 1 above), place microscope on a cleared desk.
  2. See how the cord is neatly wrapped around the base (we hope): not twisted or bent back, and the plug is securely tucked in under the cord. Always rewind the cord in this configuration.
  3. Draw a right side view of the microscope (oculars point to L), label or explain all of the following. Briefly note various functions. (You may be tested on any of these...):
light path
base
power switch
lamp and housing
lamp rheostat
arm
stage
iris diaphragm & lever
condenser
condenser positioning knob
mechanical stage, retaining screws
mech stage positioning knobs		 slide retainer and thumb knob
coarse focus (show dir to lower)
fine focus
objectives
parfocal objective lenses
achromatic coating
nosepiece or turret
optical head
optical head retaining screw
oculars
binocular focus (L adjustable ocular)
interpupillary distance

Here is a view of the left side view of the microscope.

NOTE ESPECIALLY:
 

lamp rheostat use at as low a setting which produces adequate lighting (around 6-7). Too high a setting generates excessive heat and reduces the life of the $50 bulb.
 iris diaphragm lever move side to side while viewing through the ocular. What happens?
Coarse and Fine focus Which direction do you rotate the coarse focus knob to lower the stage? Memorize this direction. Note: the fine focus moves the stage almost imperceptibly
Nosepiece (turret) With the stage lowered, rotate the nose piece so that each of the objectives is successively pointing down, clicking when the objective is in proper position
Ocular What is the magnifying power of the ocular? What would the power of magnification be if you were using the 4x objective with this ocular?