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Preliminary plans for 3rd multi-immersion objective lens

We are going public with tentative plans for our third multi-immersion objective lens. By end-2019 we plan to finalize the design based on feedback, plus decide how large of an order to place for them (the larger the order the smaller the cost, but we have to be assured they will sell). So please get in touch if you are interested, and please give your feedback!  The current plan is to have them available late spring 2020.

This objective lens design was inspired by three use cases:

  1. Lattice light sheet or similar high-NA live cell light sheet imaging. It can replace the Nikon 25x/1.1 W objective which is commonly used but far from ideal for this application.
  2. Imaging cleared tissue with higher NA than any existing cleared tissue or glycerin objective. Working distance and field of view are relatively modest for this application but sufficient to be useful for some samples.
  3. Single-objective light sheet with a relatively long working distance.

Here is a brief overview of the preliminary specifications:

  • NA 1.05 in water, NA 1.22 in ECi or BABB
  • 48x in water, 56x in ECi or BABB (with 200 mm tube lens)
  • 0.5 mm diameter FOV
  • 3.05 mm working distance
  • designed for 1P light sheet (plan-corrected, optimized for visible)
  • 75 mm parfocal distance, M25x0.75 threads, 57° mechanical half-angle (fits in place of Nikon 25x/1.1w)
  • price $25k-$30k depending on production run size

Like our other multi-immersion objectives it features a curved first surface which allows it to be used in any dipping medium without a correction collar. Tentatively the chromatic correction is optimized for water and degrades somewhat in organic media, but we could change this before finalizing.  We hope to make it resistant to dipping in harsh organic chemicals like DBE and BABB like our other multi-immersion objectives but we aren’t 100% sure whether that will be possible yet (if that’s crucial to you please let me know); for sure in will work with water, glycerin, FocusClear, etc.

I’d love to talk in person about this lens if you happen to be attending SfN Oct 21-23, LSFM Dec 4-6, or ASCB/EMBO Dec 8-10. Otherwise please contact me by email for further details and to give your feedback. My “survey questions” include the following:

  • How would you use this objective lens? (e.g. lattice, cleared tissue, and/or SOLS)
  • Any specification you would like changed? How?
  • How certain would you purchase it within 2 years?

Our second objective lens is here

Our popular multi-immersion objective lens now has a much-anticipated sibling, another multi-immersion lens with increased NA of 0.7.  It is available for immediate sale.

Here are some glamour shots:

 

Like the original NA 0.4 lens, this objective lens is targeted at light sheet imaging of cleared tissue but is useful for a myriad of other applications.  With NA of 0.7, the new lens offers a 3x improvement in both photon-gathering ability and axial resolution, with a 1.75x improvement in lateral resolution.  The trade-offs for increased NA are a modest reduction in working distance  (10 vs. 12 mm), a modest reduction in field of view (1.0 vs. 1.2 mm), more bulk (same OD, parfocal 83 vs. 61 mm, 70% more mass), and higher price (by 60%).

Both objective lenses work in any medium, from water to oil and even in air, with no need for a correction collar.  This is possible because of a curved first surface which minimizes refraction as light enters the lens.  Both are dipping lenses; i.e. they assume uniform refractive index from objective surface to image plane.  Both are robust to dipping in harsh media including BABB and DBE.

The nominal magnification of the new objective is ~24x with a 200 mm f.l. tube lens, which is a compromise choice.  The field of view permits demagnifying with a 160mm tube lens.  On the other hand, achieving NA-limited resolution with GFP-labeled samples requires a 250 mm tube lens.  (These assume today’s typical sCMOS sensors with 6.5 µm dexel pitch in a 2k square array.)  Note that the exact magnification and NA are proportional to the immersion medium’s refractive index; the stated values are for RI 1.45.

These objective lenses are the fruits of a collaboration between ASI and Special Optics.  ASI identifies needs and chooses specifications, Special Optics does the detailed design work and manufacturing, and ASI is the sole distributor but sells them freely.  Custom optics are cost-prohibitive in small quantities, but by designing an optic that is useful to many people (and companies) then economies of scale provide a reasonable price for everyone.  We plan to create more objective lenses in the future; if you have ideas or unmet needs please talk with me.

You can find more about these objective lens on our website (overview or details).  We have two lenses dedicated for short demo/evaluations; please email me if you want to get on the demo list or if you have any questions.