Polarization-based optical angle-filters disclosed herein can be engineered to transmit a prescribed amount of light as a function of incidence angle and azimuth. Such filters can transmit light without introducing artifacts, making them suitable for the image-path of an optical system. One example may include an angle-filter having an input circular polarizer, an analyzing circular polarizer, and a retarder positioned between the circular polarizers, the retarder having a thickness-direction retardation. The thickness-direction retardation of the retarder (R.sub.th) is selected to produce a prescribed angle-of-incidence dependent transmission function, and the circular polarizers reduce the amount of azimuth-dependence in the transmission function.

A transmittance-variable device is provided in the present application. The present application provides a transmittance-variable device, which can be applied to various applications without causing problems such as a crosstalk phenomenon, a rainbow phenomenon or a mirroring phenomenon, while having excellent transmittance-variable characteristics.

The application provides an augmented reality display device comprising a projection source module (10) and an optical path module, wherein the projection source module (10) comprises a projection source (12), the projection source (12) has a curved light outgoing surface (12a), virtual image light (VL) is projected out of the projection source (12) via the curved light outgoing surface (12a), and the optical path module comprises a beamsplitter (20) and a reflector (60), wherein the virtual image light (VL) projected out of the projection source module (10) is incident on the beamsplitter (20), reflected by the beamsplitter (20) onto the reflector (60), reflected by the reflector (60), and then transmitted through the beamsplitter (20), entering a human eye (E) eventually. The application also provides a wearable augmented reality system comprising the augmented reality display device and a projection source module for the augmented reality display device.

A wearable display system includes an eyepiece stack having a world side and a user side opposite the world side, wherein during use a user positioned on the user side views displayed images delivered by the system via the eyepiece stack which augment the user's view of the user's environment. The wearable display system also includes an angularly selective film arranged on the world side of the of the eyepiece stack. The angularly selective film includes a polarization adjusting film arranged between pair of linear polarizers. The linear polarizers and polarization adjusting film significantly reduces transmission of visible light incident on the angularly selective film at large angles of incidence without significantly reducing transmission of light incident on the angularly selective film at small angles of incidence.

A three (or more) polarizer arrangement is used to demonstrate a wide-angle variable-neutral-density (VND) filter that has both contrast uniformity and color uniformity. According to one embodiment, the outer polarizers effectively counter-rotate with respect to a fixed center polarizer as a means of compensating for transmission non-uniformity associated with geometrical polarization distortions experienced by off-normal rays. In particular, the achromatic compensation arrangement enables angle uniformity relative to normal-incidence transmission when the number of stops of attenuation grows large (e.g. 10-stops, or OD3). The filters are useful for cameras or instrumentation allowing mechanical or electromechanical tuning.

A light shielding member of the present invention includes a first polarizing plate, a second polarizing plate facing the first polarizing plate, and a thermosensitive sheet interposed between the first polarizing plate and the second polarizing plate, in which the first polarizing plate and the second polarizing plate are positioned so that their respective transmission axes are different from each other, and the thermosensitive sheet contains a side chain crystal polymer that crystallizes at a temperature lower than the melting point and exhibits fluidity at a temperature of the melting point or higher. The light shielding member may transmit light at a temperature lower than the melting point and may not transmit light at a temperature of the melting point or higher, when light travels from one of the first polarizing plate and the second polarizing plate toward the other.

An imaging apparatus includes a first optical system, a first separation optical system that separates the light transmitted through the first optical system into the first wavelength range light and the second wavelength range light, a second optical system that transmits the first wavelength range light obtained by the first separation optical system, a third optical system that transmits the second wavelength range light obtained by the first separation optical system, a first image sensor that receives the first wavelength range light, a second image sensor that receives the second wavelength range light, and a first light source that emits the first wavelength range light, in which the first optical system emits the first wavelength range light emitted from the first light source to a subject, and transmits subject light including first wavelength range reflected light obtained by reflecting the first wavelength range light by the subject.

The present disclosure provides a polarization attenuator and a polarization attenuation method to solve the problem of polarization dependent loss of optical devices, or to be used in optical devices or systems as a polarizer structure. The polarization attenuator comprises a first main waveguide, an offset waveguide and a second main waveguide which are arranged in sequence, wherein an output surface of the first main waveguide partially overlaps an input surface of the offset waveguide; an output surface of the offset waveguide partially overlaps an input surface of the second main waveguide; the first main waveguide or the second main waveguide supports fundamental modes and supports at least one high order mode. Meanwhile, the present disclosure further provides the polarization attenuation method comprising following steps: 1) optical signals enter the first main waveguide; 2) the optical signals excite high order modes at a joint of the first main waveguide and the offset waveguide; and 3) the signals are mixed again at a joint of the second main waveguide and the offset waveguide, and power between a fundamental mode and high order modes of the offset waveguide is redistributed between the fundamental mode and the high order mode of the second main waveguide.

The present disclosure relates to an assembly for an electronic device comprising: a display screen; an optical light emitter adapted to emit an Infrared or near Infrared light beam through the display screen; the optical light emitter and the display screen being of the type that, when an unpolarized light beam from the optical light emitter passes through a region of the display screen, a white spot of a first intensity is formed in the region; a light polarizer positioned between the optical light emitter and the display screen, the light polarizer being orientated such that a white spot of a second intensity, lower than the first intensity, is formed when the light beam, from the optical light emitter and polarized by the light polarizer, passes through the region of the display screen.

A method and system for reducing the effects of glare in a system comprising a picture generating unit, such as a holographic projector. The system may be a head-up display (HUD), which is configured to display a picture to a viewer, without requiring the user to look away from their usual viewpoint. The HUD system may be comprised within a vehicle. The glare in the system may be caused by light being incident on a surface comprising a screen or a window, through which the user looks at their usual viewpoint. The surface may comprise a windshield in a vehicle. The light that causes the glare may be ambient light. The method and system are provided for reducing the effects of glare in a system that comprises a waveguide in conjunction with the picture generating unit. The waveguide may be operable to act as an exit pupil expander.