PANASONIC LUMIX G VARIO 7-14mm f/4 ASPH.

US 2010/0194930 A1 — Kyoichi Miyazaki, Keiichi Zaitsu

16 elements / 12 groups
7.2006-13.6229 mm patent EFL
f/4 constant-aperture Micro Four Thirds zoom
2 aspherical surfaces
4 ED-class elements
0.25 m close focus

Focus Mechanism

Internal rear focus by G4/L14 moving image-side. Close-focus spacings are paraxially solved for 0.25 m because the patent publishes infinity zoom spacings only.

Optical Elements (16 physical)

ElementTypeGlass
L1Negative MeniscusLanthanum flint class (804/465, catalog match uncertain)
L2Negative MeniscusLanthanum flint class (804/465, catalog match uncertain)
L3Negative Meniscus (1x Asph)High-index lanthanum flint class (808/409, catalog match uncertain)
L4Biconcave NegativeS-FPL51 / FCD1 class (ED fluorophosphate crown)
L5Positive MeniscusDense lanthanum flint class (806/333, NBFD15/H-ZLaF56 class)
L6Negative MeniscusLanthanum flint class (743/492, S-LAM60/H-LaF53/NBF1 class)
L7Positive MeniscusDense flint class (673/322, E-FD5/SF5 class)
L8Negative MeniscusS-TIH53 (OHARA)
L9Biconvex PositiveN-BK7 / S-BSL7 class (borosilicate crown)
L10Biconcave NegativeN-BK7 / S-BSL7 class (borosilicate crown)
L11Biconvex PositiveS-FPL51 / FCD1 class (ED fluorophosphate crown)
L12Positive MeniscusS-FPL51 / FCD1 class (ED fluorophosphate crown)
L13Biconvex PositiveS-FPL51 / FCD1 class (ED fluorophosphate crown)
L14Negative MeniscusS-NSL3 (OHARA)
L15Negative MeniscusS-TIH6 / N-SF6 class (OHARA/Schott dense flint)
L16Biconvex Positive (1x Asph)Unmatched crown class (523/701, likely phosphate/fluorophosphate)