For the objective lens, use the oil immersion objective lens marked “Oil.”
Additionally, the black line at the tip of the lens indicates oil immersion objective lens.
Items to prepare
Prepare an immersion oil specifically for immersion objective lens, lens paper, and benzene or anhydrous ethanol for cleaning after use.
Dripping immersion oil
Slowly turn the objective used to find the part you want to observe, remove it from the optical path, and drop a immersion oil on the specimen (above the condenser lens).
Slowly enter the 100X objective into the beam path, taking care not to come in any bubbles.
Checking for air bubbles
Remove either the left or right eyepiece, and open the aperture diaphragm fully. Look into the eyepiece tube and check the objective lens pupil (a bright round part). If air bubbles are visible as shown in figure, remove them.
Eliminating air bubbles
Try ① and ② to eliminate air bubbles.
①Rotate the nosepiece to move the objective with immersed oil back and forth.
②If there is not enough oil, add more oil.
If the air bubbles have not been eliminated even after completing steps ① and ②, wipe off the oil and reapply the oil immersion.
* To avoid getting air bubbles in the oil bottle, turn the nozzle up vertically after dripping the oil and relax the pinched finger.