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2. Insert microscope plug into matched voltage outlet. On Models 131, 131-CLED & 132, flip on/off power switch located
on base to “ON” position. On Model 132-CLED, rotate on/off power switch located on base to “ON” position.
3. Rotate coarse focus knobs to move stage down (away) from objective lens as far as possible.
4. Place specimen slide, cover slip facing up, on stage with specimen centered over condenser lens in middle of stage.
5. Rotate disc diaphragm until largest aperture is positioned beneath condenser in center of stage.
6. Turn the objective turret until the 4x (smallest) objective lens “clicks” into position in the optical path. Note that each
time you change from one objective lens to another you should turn the turret until you hear the “click”, which
indicates that the lens is properly indexed in the optical path.
7. While looking through the eyepiece, rotate coarse focusing knobs until specimen comes into focus. If image does not
appear in field of view, move specimen slide slightly until image appears in field of view.
8. Adjust fine focus controls until specimen is in sharp focus.
9. Turn the disc diaphragm, observing that different apertures affect the sharpness of the image. Turn diaphragm until
sharpest possible image is obtained. Note that when turning the disc diaphragm, you should hear a “click” as each
aperture comes into proper position under the condenser lens. If aperture is not properly positioned, you will observe
shadows in the field of view when looking through the microscope.
10. Changing magnification
a. Magnification is changed by rotating objective turret until different objective lens is moved into optical path.
Always turn turret until you hear the “click”, indicating that lens is properly indexed. Otherwise, you will not be
able to see anything when looking through the microscope.
b. Standard lenses provided with your microscope are a widefield 10x eyepiece (two eyepieces supplied with
models 132 and 132-CLED). 4x. 10x, and 40x objectives. The 40x objective lens has a special spring retractable
mechanism which retracts slightly if front of lens comes in contact with the specimen slide. See chart below for
specifications on objectives.
Objective Specification Chart
Objective
N.A.
Color Code
Ring
Field of
View
Working
Distance
Magnification with
WF10X eyepiece
Din 4X
0.10
Red
4.5mm
18.5mm
40X
Din 10X
0.25
Yellow
1.8mm
6.4mm
100X
Din 40X retractable
0.65
Blue
0.45mm
0.5mm
400X
c. Also note that each objective has a color ring, which permits you to instruct changes in magnification by referring
to an easily observed color rather than to a number.
d. The microscope has been parfocalled at the factory, which allows easy change from one magnification to another,
requiring little or no adjustment of the fine focus knobs.
e. As magnification is increased, the field of view (area of specimen seen through the microscope) will decrease.
That is why it is easier to find the specific area of interest on the specimen by starting with the lowest 4x objective
lens, before increasing magnification with the 10x or 40x objective lens.
f.
NOTE: Care must be taken when rotating the 40x objective into place. This lens has a spring retractable
mechanism which retracts slightly into its housing if the front of the lens strikes the specimen slide. With fine
focus adjustment at mid-range, the rack stop has been adjusted at the factory to assure the 40x lens will clear the
thickness of a normal specimen slide and cover slip. However, if the rack stop has been improperly adjusted, or if
using a thicker than normal slide or cover slip, moving the 40x lens too quickly or carelessly could cause damage
to the front lens element or to the slide.