Nikon CFI Plan Fluor 20x MI Multi-Immersion Objective (NA 0.75, Oil/Water/Glycerin/Silicone, Infinity)

The Nikon CFI Plan Fluor 20× MI is one of the most versatile objectives available for biological microscopy — supporting oil (n=1.515), water (n=1.333), glycerin (n≈1.45), and silicone (n=1.40) immersion in a single objective with a correction collar for refractive index adjustment. This multi-immersion capability eliminates the need to swap objectives when changing between specimen types or imaging conditions: oil immersion for maximum NA on fixed specimens, water immersion for live-cell imaging in aqueous media, glycerin for refractive index matching to biological tissue, and silicone for deep tissue imaging where silicone’s refractive index (n=1.40) closely matches biological cytoplasm (~1.38). The correction collar allows fine adjustment of spherical aberration correction for each immersion medium, ensuring optimal image quality regardless of the immersion type used. The Plan Fluor fluorite design provides excellent chromatic correction and high UV-visible transmission for multi-channel fluorescence imaging. At 20× with NA 0.75, this objective provides a wide field of view for imaging large specimens, organoids, tissue sections, and multi-cell preparations across all immersion conditions. This unit is offered in excellent condition with flawless optics at a significant discount to the new list price of $5,275. Compatible with Nikon CFI series microscopes. Catalog number MRH07241.