Patent ID: 11940710
Assignee: JAPAN DISPLAY INC.
Field: Optics (Instruments)
Classification: CPC G  F | IPC G

Claim 2:
3. An illumination device comprising:
a first liquid crystal cell comprising a first substrate, a second substrate opposed to the first substrate, and a first liquid crystal layer held between the first substrate and the second substrate, the first substrate comprising a first annular shaped electrode and a second annular shaped electrode surrounding the first annular shaped electrode;
a second liquid crystal cell comprising a third substrate, a fourth substrate opposed to the third substrate, and a second liquid crystal layer held between the third substrate and the fourth substrate, the third substrate comprising a third annular shaped electrode and a fourth annular shaped electrode surrounding the third annular shaped electrode;
a polarization conversion element disposed between the first liquid crystal cell and the second liquid crystal cell; and
a light source emitting light into the first liquid crystal cell, wherein
a center of the first annular shaped electrode and a center of the third annular shaped electrode overlap in planar view,
the polarization conversion element comprises a fifth substrate comprising a fifth alignment film, a sixth substrate comprising a sixth alignment film, and a third liquid crystal layer held between the fifth substrate and the sixth substrate,
the fifth alignment film and the sixth alignment film are horizontal alignment films,
an alignment treatment directions of the fifth alignment film and an alignment treatment directions of the sixth alignment film intersect each other, and
the third liquid crystal layer contains twist-aligned liquid crystal molecules.