2006-10-01 12:40:25 · 3 answers · asked by nushnush 1 in Education & Reference ➔ Higher Education (University +)
-Bacteria are extremely small and you need a 100x objective to see them properly. The 100 X objective is an oil immersion objective. If you use just air then the refraction of the light will be too great and the image will be distorted considerably. On a microscope, objectives up to 40x are usually non-oil., 63X and above are oil. The reason is stated below, I quote from a website:
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"The most powerful lens of the light microscope is the 100x oil immersion objective. Because light is refracted every time it passes through a medium with a different refractive index, (air to glass or vice versa) the quality of the image is reduced with each passage. Thus, by reducing the number of such passages to a minimum, the clarity, brilliance and resolving power is preserved.
Immersion oil has been formulated so that it has a refractive index identical to that of glass.Thus there is no refraction of light when it passes from glass to oil and vice versa. "
2006-10-01 12:49:59 · answer #1 · answered by ♪ ♫ ☮ NYbron ☮ ♪ ♫ 6 · 0⤊ 0⤋
putting a drop of oil with a similar refractive index as glass between the conceal slip and purpose lens removes 2 refractive surfaces, so as that magnifications of 1000x or better could be executed on a similar time as nonetheless conserving sturdy determination.
2016-12-15 18:01:57 · answer #2 · answered by vanderlinden 3 · 0⤊ 0⤋
As far as i know it it is with 40x and higher you need to use oil and I believe it is to protect the lens and make searching under mag easier
2006-10-01 12:44:32 · answer #3 · answered by twist 2 · 0⤊ 0⤋