SONY FE 20mm f/1.8 G

WO 2020/213337 A1 — Kota Omiya, Tetsuichiro Okumura

14 ELEMENTS / 12 GROUPS
20 mm (scaled from 19.5069 mm paraxial)
f/1.8 marketed / f/1.85 patent
94° FULL-FRAME FIELD
4 ASPHERICAL SURFACES / 2 ELEMENTS
3 ED-CLASS ELEMENTS

Focus Mechanism

Inner focus: GR2 translates 5.536 mm objectward from the patent infinity to close-focus state.

Optical Elements (14 physical)

ElementTypeGlass
L11Negative MeniscusS-LAL18 (OHARA)
L12Negative Meniscus (ED)FCD705 (HOYA)
L13Neg. Meniscus (2× Asph)M-BACD12 (HOYA)
L14Positive MeniscusS-NPH5 (OHARA)
L15Negative MeniscusS-TIH13 (OHARA)
L16Biconvex PositiveS-LAH58 (OHARA)
L21Biconvex Positive (ED)ED fluorophosphate 497/816 class (FCD1 / S-FPL51 / J-FK01A; vendor undetermined)
L22Negative MeniscusS-TIH4 (OHARA)
L23Biconvex Positive (ED)ED fluorophosphate 497/816 class (FCD1 / S-FPL51 / J-FK01A; vendor undetermined)
L24Biconcave NegativeS-NBH56 (OHARA)
L25Biconvex PositiveFDS18 (HOYA)
L26Biconcave NegativeS-NBH56 (OHARA)
L27Biconcave Negative (2× Asph)M-TAFD305 (HOYA)
L31Biconvex PositiveBSC7 (HOYA)