PENTAX HD D FA* 70-200mm f/2.8 ED DC AW

US 2016/0103303 A1 — Masakazu Saori

19 ELEMENTS / 15 GROUPS (PATENT)
19 ELEMENTS / 16 GROUPS (MARKETED)
70-200mm f/2.8 (MARKETED)
72.06-194.00mm f/2.9 (PATENT)
43.28mm IMAGE CIRCLE
ALL-SPHERICAL INTERNAL ZOOM

Focus Mechanism

CONSTRAINED_RECONSTRUCTION: G3 alone translates toward the image at closer focus. At 1.2 m from the fixed image plane, the solved G3 shifts are 3.287999 mm (72.06 mm), 5.615212 mm (100 mm), and 15.514881 mm (194 mm); d15+d20 is conserved at each zoom station. The patent publishes the direction and mechanism but no finite-focus spacing table.

Optical Elements (19 physical)

ElementTypeGlass
L1Negative Meniscus, concave to imageS-LAH60 (OHARA)
L2Positive Meniscus, convex to objectS-FPL51 (OHARA)
L3Biconvex PositiveS-FPL53 (OHARA)
L4Positive Meniscus, convex to objectS-FPM2 (OHARA)
L5Positive Meniscus, convex to imageS-LAH95 (OHARA)
L6Biconcave NegativeS-LAH59 (OHARA)
L7Biconcave NegativeS-FPM2 (OHARA)
L8Biconvex PositiveS-TIH6 (OHARA)
L9Biconcave NegativeS-LAH55V (OHARA)
L10Biconvex PositiveS-LAH65V (OHARA)
L11Positive Meniscus, convex to imageS-FPL51 (OHARA)
L12Negative Meniscus, convex to imageS-TIH53W (OHARA)
L13Negative Meniscus, convex to imageS-NBM51 (OHARA)
L14Biconvex PositiveS-FPM2 (OHARA)
L15Positive Meniscus, convex to objectS-FPL53 (OHARA)
L16Biconcave NegativeS-LAH51 (OHARA)
L17Biconvex PositiveS-FPM2 (OHARA)
L18Negative Meniscus, convex to imageS-LAH59 (OHARA)
L19Positive Meniscus, convex to imageS-LAH95 (OHARA)