Field of view calculation

[ashlyjohnes]

Hi all

I've been checking light field microscope, to see if they answer my needs.
*my needs are wide field of view 5mm x 5mm (after magnification) at magnification of 40x.

I think the following examples will answer my needs,
But, I'm trying to understand what will be my final field of view in mm^2. And I'm not sure how to do it.

example 1 (I'm not sure I need an arc)
image
https://www.ncbi.nlm.nih.gov/pmc/articl ... gure/g001/
article - image origin
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4574646/

example 2
https://www.google.com/patents/US20140183334

example 3 - technology example
https://www.cnet.com/products/lytro-lig ... era/specs/

How can I calc the FOV?

[apochronaut]

Since these are non-scanning systems, the potential f.o.v., will be strictly determined by the f.o.v. of the objective employed. You will note that , in the first example given , the Olympus 10X .40 N.A. objective is providing a f.o.v. of 2.65mm. This represents a 2,650 μm f.o.v. capability of that Olympus objective. The objective probably has a greater f.o.v. available, maybe up to 3000 μm or more but at some point the diameter of the lens itself, imposes limitations on what it can see and register with adequate planarity.

Under the same conditions, a similarly configured 40X objective will be capable of seeing, 662.5 μm, and somewhat more, if the light condensing system and optical pathways in the instrument allow it. You might get 1mm out of it.

It is theoretically possible to mfg. a 40X objective with a 5mm f.o.v. but the necessary size of the glass elements would make such an objective, very expensive.....especially since there would be a limited market for it.

In a scanning system or some form of stitching system the objective f.o.v. could be additive in the x and y planes.

I hope I understand what I am seeing in your links correctly. They look to be plural sensing systems for the purpose of gaining information in the z plane and therefore creating a 3-D image, not specifically increasing the f.o.v.

[ashlyjohnes]

Hi apochronaut, thanks for your help again.

someone told me that if I use cmos 35mm sensor with microlenses, as in the following example or how Lytro company uses,
It could increase my FOV dramatically (not necessarily 5mm x 5mm)
Is that true?
How can I calc that?

https://www.google.com/patents/US20140183334

*the 3d isn't an actual need

[Hobbyst46]

I notice that the field of view shown in Fig3 of the article is ~3.2 mm, as I calculate from the 400um scale bar and the image width;
Further, there are two relay lenses here, not just the objective.

[apochronaut]

I don't see that as possible, beyond the possibility of capturing whatever extra f.o.v. that the objective sees, which in the original design is being vignetted by the eyepiece field stop. Objective lenses, typically have a larger f.o.v. than that used in the optical path as viewed but the extra field very quickly deteriorates into a poorly corrected peripheral part of the image. In other words , manufacturers, usually take as full advantage of their optical designs as possible, otherwise they are engineering into a marketless void.

With respect to microlenses : in theory an array of peripheral microlenses could be designed to correct for peripheral aberrations of a given objective and therefore increase the f.o.v. by allowing that portion of the objective's image to be useful but the extra percentage would be fairly small and the cost of the microlens array would not be justifiable.

It is important not to confuse the actual field with the apparent field. The apparent field can be increased wantonly on any microscope but the actual field is fixed by the capability of the objective.