An electrically switchable optical modulator for modulating an optical wavefront transmitted therethrough, comprising a birefringent first optical element and a birefringent second optical element each having respective ordinary and extraordinary refractive indices. A birefringent liquid crystal material is sandwiched between the first and second optical elements. The extraordinary refractive index of the liquid crystal material is electrically switchable between: a first state in which it has a first value; and, a second state in which it has a second value different from the first value. One or both of the first value and the second value is un-matched to the extraordinary refractive index of the first optical element in respect of light polarised in a first direction of linear polarisation, and is un-matched to the extraordinary refractive index of the second optical element in respect of light polarised in a second direction of linear polarisation orthogonal to the first direction. This switchably renders a relative contrast in extraordinary refractive index as between the liquid crystal material and the first and second optical elements for modulating said wavefront.

Provided is an augmented reality device including a display element configured to generate a first image, an optical coupler including a first surface through which the first image is input and a second surface opposite the first surface and configured to output light that is input through the first surface to the second surface and output light that is input through the second surface to the first surface, a reflective polarizer provided on the side of the second surface of the optical coupler and configured to reflect light with a first polarization and transmit light with a second polarization different from the first polarization, and a polarization selective variable focus lens provided in a traveling path of the light with the first polarization reflected by the reflective polarizer and having variable refractive power with respect to the light with the first polarization.

According to one embodiment, a display device includes an illumination device, a display panel modulating light from the illumination device and emitting image light, a polarized light modulation element transmitting the image light from the display panel and diffusing external light, and a magnification mirror magnifying an image by the image light transmitted through the polarized light modulation element. The polarized light modulation element is a liquid crystal lens including a first substrate, a second substrate, a liquid crystal layer held between the first substrate and the second substrate, and a first control electrode and a second control electrode applying voltage to the liquid crystal layer.

An imaging apparatus including: an image sensor having a photo-sensitive surface; an optical device arranged on an optical path of light incidenting on the photo-sensitive surface, the optical device being electrically controllable to have a spatially variable focal length; and a processor configured to: generate and send a drive signal to the optical device to compensate for field curvature of optical device by adjusting focal lengths of different portions of the optical device to different extents, wherein a focal length of a first portion of the optical device is higher than a focal length of a second portion of the optical device surrounding the first portion; and control the image sensor to capture a distorted image of a real-world environment.

A liquid crystal lens includes a first substrate and a second substrate opposite to each other, and a liquid crystal layer disposed between the first substrate and the second substrate. The first substrate includes a first base substrate, a plurality of first electrodes, and a first alignment layer, wherein two adjacent first electrodes of the plurality of first electrodes are insulated from each other, an orthographic projection of each of the plurality of first electrodes on a first surface is an axisymmetric pattern and a centrosymmetric pattern, and center points of the orthographic projections of the plurality of first electrodes on the first surface are in coincidence with each other. The second substrate includes a second base substrate, a plurality of second electrodes, and a second alignment layer, wherein an orientation of the first alignment layer and an orientation of the second alignment layer are perpendicular to each other.

An embodiment provides a liquid lens including a first plate comprising a cavity formed therein to accommodate a first liquid, which is non-conductive, and a second liquid, which is conductive, therein, the first plate being conductive, an electrode disposed on the first plate, a second plate disposed on the electrode, the second plate being non-conductive, a third plate disposed under the first plate, and an insulation layer disposed between the first plate and the electrode and between the second liquid and the first plate.

A variable focal length lens apparatus is provided with a variable focal length lens in which a focusing position periodically changes in response to a drive signal that is input; a light source that emits detection light at an object via the variable focal length lens; an photodetector that receives the detection light that is reflected by the object, and outputs a light detection signal; a signal processor that, based on the light detection signal that is input, outputs a light emission signal that is synchronized to a focusing time point where the detection light is focused on a surface of the object; an illuminator that provides pulse illumination to the object with illuminating light, based on the light emission signal that is input; and an image capturer that captures an image of the object through the variable focal length lens.

A flexible optical element adopting liquid crystals (LCs) as the materials for realizing electrically tunable optics is foldable. A method for manufacturing the flexible element includes patterned photo-polymerization. The LC optics can include a pair of LC layers with orthogonally aligned LC directors for polarizer-free properties, flexible polymeric alignment layers, flexible substrates, and a module for controlling the electric field. The lens power of the LC optics can be changed by controlling the distribution of electric field across the optical zone. Lens power control can be provided using combinations of electrode configurations, drive signals and anchoring strengths in the alignment layers.

An image detection device includes a liquid resonant lens system whose focal point is cyclically changeable; an image detector configured to detect a detection image in a to-be-imaged region through the lens system; a pulsed illuminator configured to emit pulsed light on the to-be-imaged region in synchronization with the focal point; and an illumination controller configured to increase or decrease an illumination duration of the pulsed illuminator depending on a required light volume of the to-be-imaged region at the focal point where the pulsed illuminator emits pulsed light.

A display device with adjustable viewing angle is provided, which includes a display unit with a plurality of pixels arranged in a pixel array and emitting light for displaying image information to a user, a plurality of electro-optical lenses with adjustable optical power arranged in a lens array at the display unit, wherein each electro-optical lens is adjustable between a public mode, in which the electro-optical lens is configured to project light from the display unit towards the user within a first viewing angle, and a privacy mode, in which the electro-optical lens is configured to project the light towards the user within a second viewing angle, smaller than the first viewing angle.