An optical element and a projection image display apparatus capable of obtaining excellent tolerance to light of high luminance and high output. The optical element includes a substrate transparent to light in a used wavelength band, and a birefringent layer including an obliquely deposited film containing hafnium oxide as a main component. The projection image display apparatus includes a liquid crystal display device having the optical element, a light source for emitting light, and a projection optical system for projecting modulated light, and the liquid crystal display device is disposed in an optical path between the light source and the projection optical system.

A projector includes a light source device, a homogenization optical element, a polarization conversion element, a liquid crystal panel, an incident side polarization plate, an exit side polarization plate, a projection optical system, a first housing, a second housing, a first heat-transfer section, a second heat-transfer section, a first fan configured to feed an air current toward the first heat-transfer section and the second heat-transfer section, and a first duct in which the first heat-transfer section and the second heat-transfer section are disposed.

A liquid crystal device includes a common electrode as a first electrode, a pixel electrode as a second electrode, a liquid crystal layer to which a drive voltage is applied for one refresh period as a first refresh period, and a measurement circuit that applies an inspection voltage to the liquid crystal layer between the common electrode and the pixel electrode, sets a period that is longer than one refresh period after the application of the inspection voltage is stopped, and measures a voltage between the common electrode and the pixel electrode.

A transmissive liquid crystal panel includes a pixel region where a plurality of pixels are arrayed, a liquid crystal layer configured to modulate light for each of the pixels, an incident section configured to make the light incident on the liquid crystal layer, an emission section configured to emit, as image light, the light modulated by the liquid crystal layer, and a vapor chamber including an opening section corresponding to the pixel region, a heat receiving section around the opening section, and a heat radiating section configured to radiate heat received by heat receiving section, the vapor chamber vaporizing, with the heat received, a coolant in a liquid phase encapsulated on an inside of the vapor chamber and radiating, with the heat radiating section, heat of the coolant in a gas phase to thereby condense the coolant in the gas phase into the coolant in the liquid phase.

A liquid crystal device includes a reflection-type liquid crystal panel in which a first substrate provided with a reflective layer and a second substrate having light-transmissivity face each other via a liquid crystal layer. In the liquid crystal device, a λ/4 phase difference plate is arranged in an optical path in which light incident from the second substrate side is reflected by the reflective layer and emitted from the second substrate side, and a phase difference compensation layer such as a C plate and O plate provided integrally with the liquid crystal panel is provided in the optical path. The λ/4 phase difference plate is an inorganic material film provided on a second end surface facing the second substrate in the polarized light separating element. The phase difference compensation layer is an inorganic material film provided on a surface of the second substrate opposite to the liquid crystal layer.

An electro-optical device includes a first substrate, a second substrate bonded to the first substrate, a liquid crystal layer provided between the first substrate and the second substrate, a third substrate provided on an opposite side of the first substrate from the liquid crystal layer, and a frame configured to house the first substrate, the second substrate, and the third substrate. The frame includes a facing surface facing, via an adhesive layer, a first surface on an opposite side of the third substrate from the liquid crystal layer. The third substrate is larger than the first substrate. The frame and only the third substrate among the first substrate, the second substrate, and the third substrate are bonded to each other.

A liquid crystal apparatus includes a liquid crystal layer, a pixel electrode provided in a display region and configured to be supplied with an image signal at a first frequency, and a first electrode provided in a region outside the display region and configured to be alternately supplied with a positive polarity potential with a potential higher than a predetermined potential and a negative polarity potential with a potential lower than the predetermined potential at a second frequency lower than the first frequency such that a positive polarity period in which the positive polarity potential is supplied and a negative polarity period in which the negative polarity potential is supplied have a same length.

A light-emitting device includes a substrate, a laminated structure provided at the substrate, and a conductive layer provided at the laminated structure and configured to apply an electric current to the laminated structure. The laminated structure is provided between the substrate and the conductive layer, and includes a first semiconductor layer of a first conductive type, a second semiconductor layer of a second conductive type different from the first conductive type, and a light-emitting layer provided between the first semiconductor layer and the second semiconductor layer. The conductive layer includes a plurality of wire portions extending in a direction orthogonal to a lamination direction of the laminated structure, and is configured to polarize light generated at the light-emitting layer, and an electric current is applied to the light-emitting layer via the plurality of wire portions.

A transparent display panel and a control method and apparatus therefor, a display system, and a computer-readable storage medium. The transparent display panel includes: a liquid crystal panel (11), and a transflective optical film layer (12) disposed on one side of the liquid crystal panel (11), wherein a plurality of microstructures (31) for scattering incident light rays are provided in the transflective optical film layer (12), in order to present a projected image. The transparency level of the transparent display panel is determined by acquiring the ambient light intensity of the transparent display panel or a grayscale average of a projected image at each first region, and the light transmittance level of the liquid crystal panel is adjusted according to the transparency level, thereby improving the projection display effect.

A light source apparatus includes a plurality of light emitting apparatuses. Each of the light emitting apparatuses includes a plurality of light emitting devices each of which has a light emitting area and a non-light emitting area on an emission surface thereof that emits light. At least two light emitting apparatuses of the light emitting apparatuses constitute a light emitting apparatus group disposed such that the emission surfaces of the respective light emitting apparatuses are parallel to each other with a predetermined distance, and that a distance between light emitting areas of the respective light emitting apparatuses when viewed along a direction perpendicular to the emission surfaces of the at least two of the light emitting apparatuses is shorter than a distance between the light emitting areas of the respective light emitting apparatuses when the emission surfaces of the respective light emitting apparatuses are on the same plane.