What is the Length of a Compound Microscope?

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songoku
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TL;DR
Compound microscope uses two convex lenses, one as objective lens and one as eye piece lens. What is the length of compound microscope?
If we say "length of microscope", which distance does it refer to? Is it:

a) the tube length (L), which is the distance between the focal point of objective and focal point of eye piece lens
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OR

b) the distance (d) between objective and eye piece lens

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Thanks
 
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songoku said:
Summary:: Compound microscope uses two convex lenses, one as objective lens and one as eye piece lens. What is the length of compound microscope?

If we say "length of microscope", which distance does it refer to?
I think there is no accepted answer. The dimension that's marked on the ray diagram would be the length to consider if there is some discussion that refers to it(?). One important 'length' would be the length of the cutout in the carrying case, which would be longer than the distance between the centres of the lenses and shorter than the distance between object and eye.
Not something to worry about too much, perhaps and not part of the theory.
 
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sophiecentaur said:
I think there is no accepted answer. The dimension that's marked on the ray diagram would be the length to consider if there is some discussion that refers to it(?).
There is no specific discussion that refers to it. My teacher said length of microscope is distance between two lenses and I came across the term tube length while googling about microscope so I am confused which one is the length of microscope

One important 'length' would be the length of the cutout in the carrying case, which would be longer than the distance between the centres of the lenses and shorter than the distance between object and eye.
Not something to worry about too much, perhaps and not part of the theory.
What do you mean by length of cutout?

Thanks
 
Most optical stuff lays in a cutout hole in the carry case to stop it moving about. The width and depth of the hole are also relevant but not to the optics.
I do not think there’s an official term “length”. That can change as the focusing is adjusted .
Edit: You have already said that your teacher gave you a definition for the purpose of the lesson. Tube length will depend on all sorts of things and is of no 'optical' significance. You should stop worrying about using the correct word and concentrate on using and demanding precise descriptions to suit the context. Classifying can be a real waste of time.
 
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sophiecentaur said:
Most optical stuff lays in a cutout hole in the carry case to stop it moving about. The width and depth of the hole are also relevant but not to the optics.
I do not think there’s an official term “length”. That can change as the focusing is adjusted .
Edit: You have already said that your teacher gave you a definition for the purpose of the lesson. Tube length will depend on all sorts of things and is of no 'optical' significance. You should stop worrying about using the correct word and concentrate on using and demanding precise descriptions to suit the context. Classifying can be a real waste of time.
Thank you very much sophiecentaur
 
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