LAOWA 12mm f/2.8 Zero-D

CN205720849U Example 2 — Anhui Changgeng Optical Technology / Zhang Xiaohua

16 elements / 10 groups
Design f = 12.4999 mm
Design Fno = 2.87
2ω = 120.2°
4 aspherical surfaces / 2 aspherical elements
3 ED-class elements

Focus Mechanism

Floating focus: G1 fixed; G2 and G3 move. The patent variable-gaps encode infinity and a beta=0.02x finite-focus check, not the production 0.2x minimum-focus endpoint.

Optical Elements (16)

ElementTypeGlass
L1Negative Meniscus749547 - high-index crown class (patent nd=1.74916, vd=54.67; unresolved)
L2Neg. Meniscus (2× Asph)BACD12 / S-BAL42 class (583/595)
L3Negative MeniscusFCD1 / H-FK61 / S-FPL51 class (497/816 ED)
L4Plano-Convex PositiveE-F1 class (HOYA, 626/357)
L5Biconcave Negative835447 - high-index lanthanum class (patent nd=1.83481, vd=44.72; unresolved)
L6Biconvex PositiveFD140 class (HOYA, 762/266)
L7Negative MeniscusN-SF66 (SCHOTT) / E-FDS1 class (923/209)
L8Biconvex PositiveE-F3 class (HOYA, 613/370)
L9Biconcave NegativeTAFD35L / TAFD35 class (HOYA, 911/353)
L10Biconvex PositiveE-F2 class (HOYA, 620/363)
L11Positive MeniscusFD110 class (HOYA, 785/257)
L12Negative Meniscus904293 - dense flint class (patent nd=1.90366, vd=29.31; unresolved)
L13Biconvex PositiveFCD1 / H-FK61 / S-FPL51 class (497/816 ED)
L14Negative MeniscusTAFD35L / TAFD35 class (HOYA, 911/353)
L15Biconvex PositiveFCD1 / H-FK61 / S-FPL51 class (497/816 ED)
L16Neg. Meniscus (2× Asph)D-ZLAF81-25 (CDGM)

Analysis

Detailed analysis available in the interactive viewer above.