An improvement in contrast is achieved by suitably offsetting a phase difference produced by oblique light in a liquid-crystal panel.

An optical compensation apparatus includes a negative C-plate and two O-plates, an amount of a composite phase difference between the two O-plates and the negative C-plate in a tilt-direction cross section is substantially same as an amount of a phase difference produced by light having each of incident angles in a predetermined incident-angle range in the liquid-crystal panel, and a sign of the composite phase difference is opposite to a sign of the phase difference, the tilt-direction cross section being a cross section parallel to a tilt direction of the liquid crystal in a vertical-alignment-type liquid-crystal panel.

An optical film includes a first pattern layer including a base part and a plurality of protruding parts disposed on the base part, and having a first refractive index, and a second pattern layer disposed on the first pattern layer and having a second refractive index greater than the first refractive index. Each of the protruding parts includes a bottom surface adjacent to the base part, an upper surface opposite to the bottom surface and parallel to the bottom surface, and a side surface disposed between the bottom surface and the upper surface. The side surface includes three or more sub-inclined surfaces, inclination angles of which are different from each other, or includes a curved surface which is convex in a direction of the second pattern layer.

The invention provides a display device in which the tint is difficult to observe in a case where white display is visually confirmed from a front direction, and the tint is also difficult to observe at any azimuthal angle in a case where white display is visually confirmed from an oblique direction. A display device of the invention includes, from a viewing side, an anisotropic light absorbing layer and a self light emitting display element which emits at least red light, green light, and blue light, the self light emitting display element has a microcavity structure, the anisotropic light absorbing layer is formed of a composition containing a dichroic substance and a liquid crystal compound, the dichroic substance has a maximum absorption wavelength of 400 to 500 nm, and the anisotropic light absorbing layer satisfies a requirement represented by Expression (1) and a requirement represented by Expression (2).

1.50<Amax(60)/A(0)Expression (1)

1.00Amax(60)/Amin(60)1.20Expression (2)

An optical waveplate is provided. The optical waveplate includes a positive-C film including a first liquid crystal (LC) layer. Tilt angles of LC molecules vary along a thickness direction of the first LC layer. The optical wave also includes an LC cell disposed at a first side of the positive-C film and including a second LC layer aligned in an optically compensated bend (OCB) mode. The optical waveplate also includes a positive-A film disposed at a second side of the positive-C film. The optical waveplate further includes a negative biaxial retardation film disposed between the positive-A film and the positive-C film. The LC cell is switchable between at least two predetermined states.

An optical compensation device used in a liquid crystal display unit of the present invention includes: a first underlayer (332A) including a plurality of structures (332A1) that each includes at least two surfaces having inclination angles different from each other; a first multilayered film (332B) provided on the first underlayer (332A), and including at least two refractive index films (332b1 and, 332b2) that are alternately stacked and have refractive indices different from each other: a second underlayer (332C) including a plurality of structures (332C1) that each includes at least two surfaces having inclination angles different from each other, and being opposed to the first underlayer (332A) with the first multilayered film (332B) interposed therebetween; and a second multilayered film (332D) provided on the second underlayer (332C), and including at least two refractive index films (332d1 and 332d2) that are alternately stacked and have refractive indices different from each other, and an array pitch of the plurality of the structures (332A1 or 332C1) in each of the first underlayer (332A) and the second underlayer (332C) is smaller than a wavelength of visible light.

An optical compensation device used in a liquid crystal display unit of the present invention includes: a first underlayer (332A) including a plurality of structures (332A1) that each includes at least two surfaces having inclination angles different from each other; a first multilayered film (332B) provided on the first underlayer (332A), and including at least two refractive index films (332b1 and, 332b2) that are alternately stacked and have refractive indices different from each other: a second underlayer (332C) including a plurality of structures (332C1) that each includes at least two surfaces having inclination angles different from each other, and being opposed to the first underlayer (332A) with the first multilayered film (332B) interposed therebetween; and a second multilayered film (332D) provided on the second underlayer (332C), and including at least two refractive index films (332d1 and 332d2) that are alternately stacked and have refractive indices different from each other, and an array pitch of the plurality of the structures (332A1 or 332C1) in each of the first underlayer (332A) and the second underlayer (332C) is smaller than a wavelength of visible light.

An optical waveplate is provided. The optical waveplate includes a positive-C film including a first liquid crystal (LC) layer. Tilt angles of LC molecules vary along a thickness direction of the first LC layer. The optical wave also includes an LC cell disposed at a first side of the positive-C film and including a second LC layer aligned in an optically compensated bend (OCB) mode. The optical waveplate also includes a positive-A film disposed at a second side of the positive-C film. The optical waveplate further includes a negative biaxial retardation film disposed between the positive-A film and the positive-C film. The LC cell is switchable between at least two predetermined states.

A viewing angle switchable device including an absorptive polarizer, a reflective polarizer and an electrically controlled viewing angle switching element is provided. A transmission axis of the reflective polarizer is parallel to a transmission axis of the absorptive polarizer. The electrically controlled viewing angle switching element is disposed between the absorptive polarizer and the reflective polarizer and includes two transparent substrates, two transparent conductive layers and a liquid crystal layer including a plurality of liquid crystal molecules. When there is a potential difference between the two transparent conductive layers, an orthogonal projection of an optical axis of each of the plurality of liquid crystal molecules on the absorptive polarizer is parallel to or perpendicular to the transmission axis of the absorptive polarizer and the transmission axis of the reflective polarizer. A viewing angle switchable display module including the viewing angle switchable device is also provided.

An optical waveplate is provided. The optical waveplate includes a plurality of liquid crystal (LC) layers stacked together. At least one of the plurality of LC layers includes LC molecules that are in-plane switchable by an external field to switch the optical waveplate between states of different phase retardances.

A beam deflector includes a first wavelength selective polarizer configured to convert a polarization state of light in a first wavelength band into a first polarization state, a first liquid crystal deflector including liquid crystal molecules and an optical path change surface to deflect light incident from the first wavelength selective polarizer, and a controller configured to control the first liquid crystal deflector to adjust an angle of the first optical path change surface.