Advanced Ellis Concept for a Fiber-Optic Fluorescent Microscope.

Klepukov, A.

doi:10.64898/2026.04.10.717647

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bioRxiv · 10.64898/2026.04.10.717647

Advanced Ellis Concept for a Fiber-Optic Fluorescent Microscope.

Klepukov, A.

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Abstract

The design of the classical fluorescence microscope has undergone few changes since the 1970s-1980s, when Ploemopak modules with filter cubes became widespread. Most of these changes have been in the replacement of mercury and xenon lamps with LED illuminators in the 2010s. However, this does not mean that this stable design cannot be improved upon. New method: The implementation of a vibrating optical fiber, positioned using a micromanipulator and connected to any suitable type of laser, enables a full spectrum of fluorescence research. This work presents an advanced version of the Ellis concept, in which light is delivered directly onto the sample, rather than into the filter cube (technical novelty).To confirm the functionality of the microscope, vibrational slices of mouse brain stained with three fluorescent markers (B3-PPC, DiI and DiD) covering most of the visible spectrum were examined. The fiber-optic illumination system eliminates the need for bulky and obsolete high-voltage plasma arc lamp units without compromising image quality (confirmed by the USAF 1951 test and SDNR assessment on fluorescent beads). Furthermore, the optical fiber mounted on manipulators is convenient and easy to integrate, for example, into stereomicroscopes for scanning large brain tissue samples.

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Klepukov, A.. 2026-04-14. Advanced Ellis Concept for a Fiber-Optic Fluorescent Microscope.. https://doi.org/10.64898/2026.04.10.717647

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