Microscope objective lenses (particularly those made for biological microscopes) often have abbreviations inscribed on them that can at times be confusing. The list below may help you decipher exactly what the inscription on your microscope objective lens stands for.
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ABBREVIATION & Explanation:
- ACHRO = Achromatic aberration correction
- EF = Extended field (The field of view is less than plan)
- PL, PLAN, PLANO = Flat field optical correction
- N, NPL = Normal field of view plan
- UPLAN = Universal plan (Brightfield, darkfield, polarized light)
- LU = Luminous universal (brightfield, darkfield, DIC, polarized light)
- PLAN APO = Apochromatic and flat field correction
- FL, FLUOR, FLUAR = Fluorite aberration correction
- L, LL, LD, LWD = Long working distance
- ELWD = Extra long working distance
- SLWD = Super long working distance
- CORR, CR = Correction collar
- I, IRIS = Adjustable numerical aperture with iris diaphragm
- OIL, OEL = Oil Immersion
- WATER, WI, WASSER = Water Immersion
- HI = Homogeneous Immersion
- GLY = Glycerin Immersion
- DIC, NIC = Differential or Nomarski interference contrast
- CF, CFI = Chrome-Free or Chrome-Free infinity corrected
- ICS = Infinity color-corrected system
- RMS = Royal Microscopical Society objective thread size
- M25, M32 = Metric 25mm or 32mm objective thread
- PHASE, PH, PC = Phase contrast
- PH 1, 2, 3 = Phase condenser annulus 1, 2, 3
- DL, DLL, DM, BM = For phase contrast: dark low, dark low low, dark medium, dark bright
- PL, PLL = For phase contrast: positive low, positive low low
- PM = For phase contrast: positive medium
- NL, NM, NH = For phase contrast: negative low, negative medium, negative high contrast
- P, PO, POL, SF = Strain-free, made for polarized light
- U, UV, Universal = UV transmitting for UV-excited epifluorescence
- M = Metallographic (no cover slip is used)
- NC, NCG = No cover slip
- EPI = Epi illumination
- TL = Transmitted light
- BBD, HD, B/D = Bright or dark field (Hell, Dunkel)
- D, DF = Darkfield
- H = For use with a heated stage
- U, UT = For use with a universal stage
- DI, MI, TI = Interferometry, Noncontact, Multiple Beam (Tolanski)