An object of the present invention is to provide an optical laminate in which optically anisotropic layers exhibiting reverse wavelength dispersibility have excellent moisture-heat resistance, and the adhesiveness between a first optically anisotropic layer and a second optically anisotropic layer is excellent; and a polarizing plate and an image display device, each using the optical laminate. The optical laminate according to an embodiment of the present invention is an optical laminate having a first optically anisotropic layer and a second optically anisotropic layer, in which both of the first optically anisotropic layer and the second optically anisotropic layer are directly laminated and consist of a liquid crystal layer, at least one of the first optically anisotropic layer or the second optically anisotropic layer exhibits reverse wavelength dispersibility, a photo-alignment polymer having a photo-alignment group and a fluorine atom or a silicon atom is present on a surface of the second optically anisotropic layer on a side in contact with the first optically anisotropic layer, and an element ratio of fluorine or silicon on the surface of the second optically anisotropic layer on the side in contact with the first optically anisotropic layer is 0.05% to 15.00% by atom.

Provided is a viewing angle control polarizing plate that has asymmetric transmission characteristics, does not cause moire even in a case of being used in combination with a high-definition image display device, and is capable of easily following a curved surface and a viewing angle control system with high productivity. The viewing angle control system includes at least a first polarizer and an optically anisotropic layer, in which an absorption axis of the first polarizer forms an angle of 45° or greater with respect to an in-plane direction, and a main axis of a refractive index of the optically anisotropic layer is tilted in the in-plane direction.

According to the present invention, provided are an optical laminate which has excellent adhesiveness between two optically anisotropic layers, and in which an A plate or a layer obtained by fixing a twist-aligned liquid crystal phase, which is as an optically anisotropic layer, has excellent liquid crystal alignment properties, a polarizing plate, and an image display device. An optical laminate of the present invention has: a first optically anisotropic layer formed of a first liquid crystal compound; a second optically anisotropic layer formed of a second liquid crystal compound; and a mixed layer which is disposed between the first optically anisotropic layer and the second optically anisotropic layer and contains a component derived from the first liquid crystal compound and a component derived from the second liquid crystal compound, the first optically anisotropic layer is a C plate, the second optically anisotropic layer is an A plate or a layer obtained by fixing a twist-aligned liquid crystal phase, the mixed layer further contains a photo-alignment compound, and in an analysis of components of the optical laminate in a depth direction by time-of-flight secondary ion mass spectrometry with ion beam irradiation from a surface of the optical laminate on a first optically anisotropic layer side toward a second optically anisotropic layer side, predetermined requirements are satisfied.

Provided are a phase difference film that has a small change in tint in a case where the phase difference film is combined with a polarizer and then applied as a circularly polarizing plate to a display device, and the display device is observed from an oblique direction at all azimuthal angles; as well as a circularly polarizing plate and a display device. The phase difference film includes a first optically anisotropic layer, a second optically anisotropic layer, a third optically anisotropic layer, and a fourth optically anisotropic layer in this order, in which the first optically anisotropic layer is a C-plate, the second optically anisotropic layer is an A-plate, the third optically anisotropic layer is a layer formed by fixing a liquid crystal compound twist-aligned along a helical axis extending in a thickness direction, and the first, second third, and fourth optically anisotropic layers have a predetermined configuration.

The disclosed electronic shutter may include (1) an optical structure including a medium through which light from an environment passes to a lens of a camera for capturing an image of the environment; and (2) a controlling circuit that (a) detects a first condition of a signal, where the first condition indicates an activation of the camera, (b) controls, in response, to the first condition, the optical structure such that the medium attains a transparent optical state, (c) detects a second condition of the signal, where the second condition indicates a deactivation of the camera, and (d) controls, in response to the second condition, the optical structure such that the medium attains a non-transparent optical state in a manner that prevents visual detection of the lens from the environment. Various other methods and systems are also disclosed.

Optical film stacks are described. More particularly, optical film stacks including a half-wave retardation layer are described. Achromatic half-wave retardation layers, including achromatic half-wave layers formed from a quarter-wave and a three-quarters-wave retardation layer, are described. Film stacks including reflective polarizers tuned to reduce wavelength dispersion of the half-wave retardation layer are also described.

A curved display device includes a first substrate, a second substrate facing the first substrate, a liquid crystal layer disposed between the first and second substrates, the liquid crystal layer including liquid crystal molecules, a first alignment layer including reactive mesogens which are polymerized with each other, the first alignment layer being disposed between the first substrate and the liquid crystal layer, and a second alignment layer disposed between the liquid crystal layer and the second substrate, where the reactive mesogens have a functional group having charges.

Optical film stacks are described. More particularly, optical film stacks including a half-wave retardation layer are described. Achromatic half-wave retardation layers, including achromatic half-wave layers formed from a quarter-wave and a three-quarters-wave retardation layer, are described. Film stacks including reflective polarizers tuned to reduce wavelength dispersion of the half-wave retardation layer are also described.

A phase delay device, its preparation method and a display equipment are provided. The phase delay device includes linear polarization layer, alignment layer and liquid crystal layer. The linear polarization layer is configured to convert received light into a linear polarization light; the alignment layer is configured to align liquid crystals of a first subpart of the liquid crystal layer based on a preset alignment angle; the liquid crystal layer is located at a side of the alignment layer away from the linear polarization layer, and includes a first subpart adjacent to the alignment layer, a second subpart having a spiral structure with a preset spiral angle and a third subpart; a liquid crystal alignment angle of the third subpart is determined based on the preset alignment angle and the preset spiral angle; birefringence of the liquid crystal layer does not decrease with an increase of visible light wavelength.

In polarization-based optical systems, preserving a state-of-polarization (SOP) over a prescribed range of incidence angles and wavelengths may be necessary. Optical materials with local normal tilted with respect to an incident ray can introduce an undesirable polarization nonuniformity that can be substantially corrected using a compensator as disclosed herein. The compensator may include a uniaxial retarder and a z-partial polarizer (ZPP). The ZPP may include a uniaxial material with an absorption axis normal to the substrate.