PENTAX HD D FA 28-105mm f/3.5-5.6 ED DC WR

US 2017/0068075 A1 — Tatsuyuki Onozaki

15 ELEMENTS / 11 GROUPS
PATENT f = 28.70–102.38 mm
PATENT f/3.6–5.7
FULL FIELD = 76.2°–23.4°
2 ASPHERICAL ELEMENTS / 3 ASPHERICAL SURFACES

Focus Mechanism

NO_INTERNAL_RECONSTRUCTION: the patent publishes infinity-focus zoom states only. All modeled infinity/close pairs are identical; the manufacturer 0.5 m minimum-focus specification is metadata only.

Optical Elements (15 physical; 16 modeled media)

ElementTypeGlass
L11Negative Meniscus847238 — optical-glass class (vendor unresolved)
L12Biconvex Positive816466 — optical-glass class (vendor unresolved)
L13Positive Meniscus816466 — optical-glass class (vendor unresolved)
L21RNegative Meniscus (1× Asph)Unmatched (synthetic resin aspherical layer; nd=1.52972, νd=42.7)
L21GNegative Meniscus883408 — optical-glass class (vendor unresolved)
L22Biconcave Negative729547 — optical-glass class (vendor unresolved)
L23Biconvex Positive728285 — optical-glass class (vendor unresolved)
L24Negative Meniscus788474 — optical-glass class (vendor unresolved)
L31Biconvex Positive697555 — optical-glass class (vendor unresolved)
L32Negative Meniscus800299 — optical-glass class (OHARA S-NBH55 candidate; vendor unresolved)
L33Biconvex Positive497816 — ED crown class (S-FPL51/FCD1/N-PK52A/J-FK01A equivalents; vendor unresolved)
L41Biconcave Negative603607 — optical-glass class (vendor unresolved)
L42Positive Meniscus847238 — optical-glass class (vendor unresolved)
L51Biconvex Positive (2× Asph)589612 — optical-glass class (vendor unresolved)
L52Biconcave Negative720347 — optical-glass class (S-NBH8/N-KZFS8 equivalents; vendor unresolved)
L53Positive Meniscus618634 — optical-glass class (vendor unresolved)