A method of calibrating a hyperspectral imaging device includes illuminating a hyperspectral imaging sensor with a light source having known spectral properties, sampling the light from the light source with the hyperspectral imaging sensor to obtain sampled spectral properties, and calibrating a performance characteristic of the hyperspectral imaging sensor based upon comparing the sampled spectral properties of the light source to the known spectral properties.

A liquid-crystal variable retarder has first and second liquid-crystal cells with respective first and second thicknesses, the second thickness being less than the first thickness. A feedback sensor provides a feedback signal indicative of a retardance of the liquid-crystal variable retarder. A controller is coupled to the feedback sensor and the first and second liquid-crystal cells. The controller is operable to apply a first signal to the first liquid-crystal cell based on a target retardance trajectory and a feedforward control model. The controller applies a second signal to the second liquid-crystal cell based on the feedback signal and the target retardance trajectory.

The present invention discloses a display device and a method of controlling the same, dedicated spectacles and a display system, thereby enabling switching between secrecy display and normal display. The display device comprises a display panel, in which two adjacent sub-pixels located in the same row are configured to display different image information, and which only displays one image of information when in a first display state displays at least two images of information when in a second display state; the display device further comprises a control panel located at a light exit side of the display panel and comprises first regions and second regions which are alternately arranged and is configured so that when the display panel is in the second display state, a polarization direction of light emitted from the display panel after passing through the first regions is different from that of light emitted from the display panel after the light passes through the second regions. The dedicated spectacles used with the display device are configured to only allow one of light passing through the first regions and light passing through the second regions to pass therethrough.

A method of operating a hyperspectral imaging device includes receiving a light beam at a liquid crystal retarding device, and driving the liquid crystal retarding device with a pre-computed voltage waveform, wherein the voltage waveform is selected to reach a target optical retardance over time for the liquid crystal retarding device.

Techniques are disclosed relating to the transmission of data based on a polarization of a light signal. In some embodiments, data may include 3D video data for viewing by a user. Systems for transmitting data may include a display device and a device for switching the polarization of a video source. Systems for receiving data may include eyewear configured to present images with orthogonal polarization to each eye. In some embodiments, the rate of switching of the polarization switcher may introduce a distortion to the optical data. A Pi-cell device may be used in some embodiments to reduce distortion based on switching speed. In some embodiments, polarization switchers may introduce a distortion based on the frequency of transmitted light. In some embodiments, optical elements including in the transmitting or receiving devices may be configured to reduce distortions based on frequency.

Techniques are disclosed relating to the transmission of data based on a polarization of a light signal. In some embodiments, data may include 3D video data for viewing by a user. Systems for transmitting data may include a display device and a device for switching the polarization of a video source. Systems for receiving data may include eyewear configured to present images with orthogonal polarization to each eye. In some embodiments, the rate of switching of the polarization switcher may introduce a distortion to the optical data. A Pi-cell device may be used in some embodiments to reduce distortion based on switching speed. In some embodiments, polarization switchers may introduce a distortion based on the frequency of transmitted light. In some embodiments, optical elements including in the transmitting or receiving devices may be configured to reduce distortions based on frequency.

Dynamic, color-changing surfaces have many applications including but not limited to displays, wearables, and active camouflage. Plasmonic nanostructures can fill this role with the advantages of ultra-small pixels, high reflectivity, and post-fabrication tuning through control of the surrounding media. However, while post-fabrication tuning have yet to cover a full red-green-blue (RGB) color basis set with a single nanostructure of singular dimensions, the present invention contemplates a novel LC-based apparatus and methods that enable such tuning and demonstrates a liquid crystal-plasmonic system that covers the full red/green/blue (RGB) color basis set, as a function only of voltage. This is accomplished through a surface morphology-induced, polarization dependent, plasmonic resonance and a combination of bulk and surface liquid crystal effects that manifest at different voltages. The resulting LC-plasmonic system provides an unprecedented color range for a single plasmonic nanostructure, eliminating the need for the three spatially static sub-pixels of current displays. The system's compatibility with existing LCD technology is possible by integrating it with a commercially available thin-film-transistor (TFT) array. The imprinted surface readily interfaces with computers to display images as well as video.

The embodiments of the invention disclose a display substrate, a method for fabricating the same and a liquid crystal display panel. The display panel is used for constructing a transflective liquid crystal display panel comprising a transmissive region and a reflective region. The display substrate comprises an alignment layer which comprises a first alignment structure in the transmissive region and a second alignment structure in the reflective region. The first alignment structure is an oblique alignment structure and the second alignment structure is a vertical alignment structure.

The present invention discloses a stereoscopic 3d projection system that is based on elliptical polarization, and more specifically a time-multiplexed stereoscopic 3d projection system that enables the viewer to observe stereoscopic 3d images on the surface of a polarization-preserving projection-screen via utilization of passive elliptically-polarized viewing-glasses. The disclosed invention provides a stereoscopic 3d projection system that is capable of operating at higher frame-rates and/or with higher optical light efficiency as compared to other prior-art technologies that are instead based on circular polarization.

An optical element comprising a stacked liquid crystal (LC) structure for rotating polarization (e.g., handedness) of an incident circularly polarized light over a broad wavelength and incident angle for head-mounted displays (HMD)s display application is proposed. The stacked LC structure has a dual cell structures, which includes at least a first LC cell and a second LC cell, and the stacked LC structure rotates the polarized light for a broad band of light (e.g., visible spectrum) over a given field a view. The performance of designed dual LC cells structures may be optimized for narrow band wavelength and a narrow incident angle for different application cases.