Lens element

A lens element comprising a lens structure, and a replica structure

• wherein either the lens structure or the replica structure comprises a blue phase LC material comprising one or more compounds of formula I
• wherein
• L11 to L16 are independently of each other H or F,
• R 11 is alkyl, which is straight chain or branched, is unsubstituted, mono- or poly-substituted by F, Cl or CN, and in which one or more CH2 groups are optionally replaced, in each case independently from one another, by —O—, —S—, —NR01—, —SiR01R02—, —CO—, —COO—, —OCO—, —OCO—O—, —S—CO—, —CO—S—, —CY 01═CY02- or —C≡C— in such a manner that O and/or S atoms are not linked directly to one another,
• Y01 and Y02 are, independently of each other, F, Cl, or CN, and alternatively one of them may be H,
• R01 and R02 are, independently of each other, H, or alkyl with 1 to 12 C-atoms,
• Z 11 is —COO— or —CF2O—and
• X11 denotes halogen, a mono- or polyhalogenated alkyl-, or alkoxy having 1 to 6 C-atoms or a mono-, di- or polyhalogenated alkenyl having 2 to 6 C-atoms.