Re: micropscop objective and telecentricity



Brett Patterson wrote:
> Hi Helpful person,
>
> OK, so if the aperture stop is at the "back aperture" (back focal
> plane),
> and therefore the "front end" of the objective does not provide a stop,
> then the NA does not change with field position. Is that correct?

Yes

>
> And does that also mean that any scanning pivot should be at the back
> aperture?

No. In general you need to scan at the aperture stop and in collimated
space. Use an eyepiece lens to collimate the light from the objective
and scan at the exit pupil (the image of the aperture stop).
(Theoretically you could scan at the aperture stop of an infinity
objective except it is not accessable.)

.

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