Revolving Nosepiece

Revolving nosepiece and objective lenses.

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To Measure Specimens (approx.)
Total Magnification
Field of View (Diameter)
40 x
4500 micrometers
100 x
1800 micrometers
400 x
450 micrometers
450 x
400 micrometers
1000 x
180 micrometers
40 X Objective Lens
4 X Objective Lens
Parfocal: the microscope will stay in approximate focus for every objective lens once the specimen is brought into focus under the low power lens.
Troubleshooting Focusing Problems
When the image can't be focused at higher powers, the most common problem is oil on the 40 x lens.
Prevention: Never back through the lenses without first cleaning the oil from the oil immersion lens.
The Cure: Using appropriate cleaning solution, clean the 40 x lens with a swab and/or lens paper. It will take a lot of scrubbing! Remember to clean the oil off the specimen slide, as well.
When the Image can't be focused at any power (except, sometimes, the 10X), the most common problem -- the slide is upside down. This happens most often when the slide doesn't have a cover slip, especially when trying to view bacteria.
Simple Columnar Epithelium 400 X
Simple Columnar Epithelium 40 X
100 X Objective Lens (Oil Immersion)
1000 X Lens; used with immersion oil filling the gap between the lens and the image. Immersion oil has the same refractive index as air but transmits a sharper image than air. Care must be taken to ALWAYS clean the lens after use. Dried oil is extremely difficult to remove and may even ruin the lens.