Re: tube lens and spherical aberration

Posted by Andreas Bruckbauer on
URL: http://confocal-microscopy-list.275.s1.nabble.com/Southeastern-Microscopy-Society-meeting-tp4640594p4642196.html

Just go the other way, from a perfect spot in the image plane to the diffuse spot in the object plane, then you are back to the standard situation. You can always reverse the light path in linear optics.

best wishes

Andreas

-----Original Message-----
From: MODEL, MICHAEL <[hidden email]>
To: [hidden email]
Sent: Fri, 26 Feb 2010 20:54
Subject: tube lens and spherical aberration

(I apologize if this is a second post, I got some strange errors from the first 

one)



Dear List



It's not a confocal question, it's strictly a wide-field question... When people 

talk about spherical aberration they typically start with a parallel beam 

falling on an objective, and then, for whatever reason, the objective fails to 

bring all the rays into a common focus. In wide-field, one has a luminous spot 

in the object space, and the effect of spherical aberration would be a failure 

of the objective to collect all the rays into a single parallel beam. Some rays 

will form a converging (or diverging) cone instead. Then, this cone will be 

received (I suspect that in the case of a diverging cone, some light may even 

get lost on its way) by a tube lens and form a blurry spot on the image plane. 

My question is, Is this situation really equivalent to the standard one 

considered in all books? (I suspect, it's not because even the distance to the 

tube lens should make a difference). But I would be very interested in the 

opinion of those who understand optics better than I do. Thanks!



Mike Model



Michael Model, Ph.D.

Confocal Microscopy,

Dpt Biological Sciences,

1275 University Esplanade,

Kent State University, Kent, OH 44242

tel. [phone]