Nikon Eclipse LV100POL Instructions Manual page 43

P-CQ quartz wedge
The P-CQ quartz wedge is used by inserting it into the slot of the intermediate tube in place of the
P-CL 1/4 λ & tint plate.
The quartz wedge is engraved with a scale and can be used for rough measurement of retardation in
the range of 1 λ to 6 λ.
1 Determination of extinction position
Rotate the stage with the specimen under the crossed Nicols to find the direction where the
part of the specimen to be measured appears darkest.
2 Determination of subtraction position
Rotate the stage 45 degree from the extinction position to the diagonal position (direction
where the specimen appears brightest). Insert the P-CQ quartz wedge into the slot of the
intermediate tube and confirm that the interference color of the section of the specimen to be
measured changes toward the lower order side. If the interference color changes toward the
higher order side, rotate the stage another 90 degree.
3 Measurement
Move the section of the specimen to be
measured to the center of the crosshairs of the
eyepiece. Next, slide the P-CQ quartz wedge
along the slot and observe that the interference
color sequentially changes. Stop sliding the
quartz wedge where the dark stripe covers the
section of the specimen to be measured.
Reading the value from the quartz wedge scale
at that time can make a rough measurement of
retardation.
Retardation can be measured even more
accurately by using the P-CS Senarmont
compensator in combination with the P-CQ
quartz wedge.
III. Operation of Each Part
Read the scale.
41