Straun, thanks for posting the link. I love weird and wonderful systems. Wonder if Harvard actually ended up using it for the specified project. What often happens with things like this is that a grad student or post-doc puts something together as a feasibility study, publishes it (and uses it for an academic requirement) and then the results of that experience are used to work with a commercial supplier who can provide something that will do the job with minimum fuss. They have a lot of plates to truck through. Do you know the outcome here?
Couple of comments. Telecentricity at the field lens is not required for film. However, it is useful at the detector plane because tele lenses can have some strange color aberrations. We built a singly telecentric lens that worked great in monochrome (what it was designed for) but multiwavelength imaging took some careful calibration and was never really aberration-free.
Yes, the optics tend to be huge. One reason is that the greater the reduction factor the more aberration and deviation from true telecentricity - so the lens becomes more like a pipe. Sill has done well with its lenses and they are used in a lot of deep imaging applications (e.g. microwell plates, machine parts).
Note that telecentric lenses are not immune to vignetting. They collect rays in parallel at the field lens, but the efficiency of collection varies from point to point. Also, any lens design is a compromise. Telecentric lenses are designed for measurement (low distortion), not optimal modulation transfer. You can get reasonable MTF out of one of these but the tolerances become difficult (= even more expensive).
Wow, that is quite a sample movement system. Fun to build if you have the budget.
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