Others include explosion proof enclosures, venting, oil immersion, powder and sand filling, and hermetic sealing.
12.
All specimens, regardless of consistency, are permanently stained prior to microscopic examination with an oil immersion lens.
13.
An "'oil immersion objective "'is an objective lens specially designed to be used in this way.
14.
This discovery remained controversial until the development of the oil immersion lens in 1884 and of superior staining methods in 1890 1891.
15.
Use of an oil immersion lens with the incorrect immersion oil, or without immersion oil altogether, will suffer from spherical aberration.
16.
Until the development of synthetic immersion oil in the 1940s, cedarwood oil was widely used for the oil immersion objective in light microscopy.
17.
With an optical microscope having a high numerical aperture and using oil immersion, the best possible resolution is 200 nm corresponding to a magnification of around 1200?
18.
Oil immersion can generally only be used on rigidly mounted specimens otherwise the surface tension of the oil can move the coverslip and so move the sample underneath.
19.
Dual dry / immersion condensers are basically oil immersion condensers that can nonetheless focus light with the same degree of precision even without oil between the top lens and the slide.
20.
Oil immersion objectives can have practical difficulties due to their shallow depth of field and extremely short working distance, which calls for the use of very thin ( 0.17mm ) cover slips, or, in an inverted microscope, thin glass-bottomed Petri dishes.
