Embodiments herein describe a focal polarization displacer with a birefringent crystal disposed within the focal region of a lens. The birefringent crystal separates optical signals into at least two separate signals based on having different polarization states and an optical axis of the birefringent crystal is set so that focal points of the two separate signals are at an output surface of the polarization displacer where the two separate signals are output from the polarization displacer. This output surface can be a surface of the birefringent crystal or a surface of additional layer coupled to the crystal such as a polarization rotator or dielectric layer.

A stereoscopic image apparatus that is capable of minimizing loss of optical energy and improving quality of a stereoscopic image is disclosed. The stereoscopic image apparatus includes a polarizing beam splitter to reflect or transmit incident light based on polarization components of the light to split the light in at least three different directions, a reflective member to reflect the light reflected by the polarizing beam splitter to a screen, at least one modulator to modulate the light reflected by the reflective member and the light transmitted through the polarizing beam splitter, and a refractive member disposed in an advancing direction of light to be incident upon the polarizing beam splitter to refract the light to be incident upon the polarizing beam splitter.

The present invention describes a liquid crystal composite tunable device for fast polarisation-independent modulation of an incident light beam comprising: (a) two supporting and functional panels, at least one of them coated with a transparent conductive electrode layer and with optionally at least one additional layer selected from an alignment layer, antireflective coating layer, thermochromic or electrochromic layer, photoconductive or photosensitive layer, and (b) a composite structure sandwiched between said two panels and made of a liquid crystal and porous microparticles infiltrated with said liquid crystal. The porous microparticles have an average refractive index approximately equals to one of the liquid crystal principal refractive indices, matching that of the liquid crystal at one orientational state (for example, parallel n.sub.∥), and exhibiting large mismatch at another orientational state (for example, perpendicular n.sub.⊥). This refractive index mismatch between said microparticles and said liquid crystal is tuned by applying an external electric or magnetic field, thermally or optically.

A patterned optical retarder including non-overlapping first (21) and second (27) regions with respective first and second major surfaces having different RMS surface roughnesses. For substantially normally incident light over a wavelength range from about 400 nm to about 1000 nm, the optical retarder has different retardances in the respective first and second regions.

A head-up display apparatus includes: a display unit, which includes a display cell and a first polarizing plate with a retardation layer arranged on an output side of the display cell, the first polarizing plate with a retardation layer including a polarizer and a first retardation layer in the stated order from the display cell side, and which is configured to output projection light; at least one reflector configured to reflect the projection light; a housing, which has an opening portion, and which is configured to store the display unit and the reflector therein; a cover member configured to cover the opening portion; and a second polarizing plate with a retardation layer, which is arranged on a housing inner side of the cover member, and which includes a polarizer and a second retardation layer in the stated order from the cover member side.

A pancake lens assembly includes a partially reflective mirror, a reflective polarizer, a quarter waveplate, a polarization-dependent optical device, and at least one polarization controller. When a light beam is introduced into the pancake lens assembly along an optical axis in a Z direction to pass through the polarization controller in a first state, a polarization direction of the light beam is converted by the polarization controller. When the light beam is introduced into the pancake lens assembly along the optical axis to pass through the polarization controller in a second state, the polarization direction of the light beam is prevented from being converted by the polarization controller.

A film stack comprises an oriented first layer comprising polyvinyl alcohol disposed on an oriented second layer comprising naphthalene dicarboxylate containing copolyester resin. The oriented second layer has in-plane birefringence Δnxy<0.02.

Liquid crystal (LC) beam control devices using a dispersion shaped (DS) half wave plate (HWP), with specific physical characteristics, allows the broadened beam to maintain significantly better the color cohesion. Beneficial aspects of using a HWP with an appropriate thickness and birefringence index which makes it inefficient in the blue wavelength spectrum, therefore reducing the blue photon depletion in the center of the broadened beam is described herein. Combinations of an homeotropic LC cell and DS HWP structures for reduced color separation, faster relaxation time and reduced ground state scattering is further described herein.

Provided are a liquid crystal diffraction element having a high diffraction efficiency irrespective of diffraction angles, an optical element including the liquid crystal diffraction element, and an image display unit, a head-mounted display, a beam steering, and a sensor including the liquid crystal diffraction element or the optical element. The liquid crystal diffraction element includes: an optically-anisotropic layer that is formed of a liquid crystal composition including a liquid crystal compound, in which the optically-anisotropic layer has a liquid crystal alignment pattern in which a direction of an optical axis derived from the liquid crystal compound changes while continuously rotating in at least one in-plane direction, in a case where a length over which the direction of the optical axis derived from the liquid crystal compound rotates by 180° in a plane is set as a single period, a length of the single period in the liquid crystal alignment pattern gradually changes in the one in-plane direction, in a cross-sectional image of the optically-anisotropic layer obtained by observing a cross-section taken in a thickness direction parallel to the one in-plane direction with a scanning electron microscope, the optically-anisotropic layer has bright portions and dark portions extending from one surface to another surface and each of the dark portions has two or more inflection points of angle, the optically-anisotropic layer has regions where tilt directions of the dark portions are different from each other in the thickness direction, and an average tilt angle of the dark portion gradually changes in the one in-plane direction.

A polymerizable liquid crystal compound represented by the following general formula (1): ##STR00001##
(the symbols in the general formula (1) are as described in the DESCRIPTION.)