Patent ID: 11874577
Assignee: SHARP KABUSHIKI KAISHA
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 0:
1. A see-through window display comprising:
a display panel having a plurality of pixels; and
a drive circuit configured to apply a voltage according to input gray scale data to the plurality of pixels,
wherein the display panel includes:
a first substrate having a pixel electrode,
a second substrate,
a liquid crystal layer interposed between the first substrate and the second substrate,
a first polarizer provided on the first substrate, the first polarizer having a first polarization axis, and
a second polarizer provided on the second substrate, the second polarizer having a second polarization axis,

when a transmittance of each of the plurality of pixels, when the drive circuit applies a minimum voltage to the plurality of pixels, is set to TW, and when a transmittance of each of the plurality of pixels, when the drive circuit applies a maximum voltage to the plurality of pixels, is set to TB, the display panel has a normally white characteristic satisfying a relationship of TW>TB, and
the normally white characteristic of the display panel has a structure in which, when:
a first axis that is parallel to an axis created by rotating the first polarization axis 45 degrees clockwise is set to an a-axis,
a second axis that is parallel to an axis created by rotating the first polarization axis 45 degrees counterclockwise is set to a b-axis,
an a-axis component of a refractive index of the liquid crystal layer is set to ‘na’ and a b-axis component of a refractive index of the liquid crystal layer is set to ‘nb’, and
a value indicating anisotropy of the refractive index of the liquid crystal layer being a difference between a refractive index of the a-axis component and a refractive index of the b-axis component is set to Δn=|na−nb|,
a first value of Δn when the voltage applied to the plurality of pixels by the drive circuit is lower than or equal to a threshold voltage indicating a boundary of alignment change of liquid crystal molecules of the liquid crystal layer is smaller than a second value of Δn when the voltage applied by the drive circuit is higher than the threshold voltage.