Take the 2-minute tour ×
Biology Stack Exchange is a question and answer site for biology researchers, academics, and students. It's 100% free, no registration required.

I am using a microscope with an LED derived light through the epi-fluorescent port of a microscope. I know that the "field of view" for a given objective is equal to the field number/magnification but I don't know that this is the actual area of illumination on the sample. In my case, I am using a 40x objective with field number 26.5.

Secondly, if I were to use a pinhole filter between the light source and the back of the objective would this limit the area of illumination so long as the pinhole was smaller than the f.o.v. dimension?

I would be grateful for any answers, most of the information I can find on beam size at sample is related to spot size calculations of resolution.

share|improve this question
add comment

1 Answer 1

Well you can always use a piece of white circular paper and draw the outline of the light onto it since it should be visible. This is a quick and dirty method that can be improved by taking a photo of the light with a camera if you have one and then comparing the distance of the edge of the paper measured with a ruler to that of the circle of light.

share|improve this answer
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.