A hologram recording device for producing a hologram that diffracts incident light includes: a laser light source; a first half-wave plate that controls a polarization direction of a light beam emitted from the laser light source; a polarizing beam splitter that reflects S-polarized light to emit the S-polarized light as an A light ray and transmits P-polarized light to emit the P-polarized light as a B light ray with respect to the light beam passing through the first half-wave plate, and splits the light beam in two directions; a first wedge prism mirror that reflects the A light ray; a second half-wave plate that polarizes the B light ray into S-polarized light; a second wedge prism mirror that reflects the S-polarized light polarized by the second half-wave plate; and a recording medium irradiated with light rays reflected by the first wedge prism mirror and the second wedge prism mirror.

A beam steering method and device are provided. The beam steering method includes outputting, from a hologram recording medium on which a plurality of signal light beams having different steering information are recorded, signal light beam having specific steering information, by making reference light having a specific characteristic incident on the hologram recording medium. The method further includes o obtaining information about an object existing in the external environment based on the output signal light.

A method for producing a hologram (1), (1) for security elements (1a) and/or security documents (1b). One or more virtual hologram planes (10) are arranged in front of and/or behind one or more virtual models (20) and/or one or more virtual hologram planes (10) are arranged such that they intersect one or more virtual models (20). One or more virtual light sources (30) are arranged on one or more partial regions of the surface (21) of one or more of the virtual models (20). One or more virtual electromagnetic fields (40) are calculated starting from at least one of the virtual light sources (30) in one or more zones (11) of the one or more virtual hologram planes (10). In the one or more zones (11), in each case, a virtual total electromagnetic field (41) is calculated on the basis of the sum of two or more, of the virtual electromagnetic fields (40) in the respective zone (11). One or more phase images (50) are calculated from the virtual total electromagnetic fields (41) in the one or more zones (11). A height profile (60) of the hologram (1) is calculated from the one or more phase images (50) and the height profile (60) of the hologram (1) is incorporated into a substrate (2) to provide the hologram (1).

A device in holographic imaging comprises: at least two light sources, wherein each of the at least two light sources is arranged to output light of a unique wavelength; and at least one holographic optical element, wherein the at least two light sources and the at least one holographic optical element are arranged in relation to each other such that light from the at least two light sources incident on the at least one holographic optical element interacts with the at least one holographic optical element to form wavefronts of similar shape for light from the different light sources.

An optical device including a first rigid substrate, a flexible holographic optical element, a transparent flexible material having a variable shear transmission property across an in-plane direction of the flexible holographic optical element, and a second rigid substrate, where the flexible holographic optical element and the transparent flexible material are located between the first and second rigid substrates, where the variable shear transmission property of the transparent flexible material transmits variable amounts of a shear force applied to the first or second rigid substrates across the in-plane direction of the flexible holographic optical element.

Techniques disclosed herein relate to optical devices. Resins with different optical properties can be deposited in different areas to provide increased optical functionality. It can be difficult to design a single photopolymer material that meets several technical requirements. Different resins can be deposited on the same substrate to make a single film with spatially varying properties. Different resins can also be applied to different substrates in a stack. By using different resins, an optical component can be made that meets several technical requirements.

A display including a plurality of pixels each including a plurality of first subpixels and a plurality of second subpixels. In pixel, when illumination light is applied to the first subpixels from a normal direction, no diffracted light emerges from the plurality of first subpixels, or first diffracted light emerges from the plurality of first subpixels in a first angular range. When illumination light is applied to the second subpixels from the normal direction, no diffracted light emerges from the plurality of second subpixels, or second diffracted light having a wavelength equal to that of the first diffracted light emerges from the plurality of second subpixels in a second angular range wider than the first angular range, at an intensity lower than that of the first diffracted light; with the pixels configured to display a continuously changing image using the first diffracted light and the second diffracted light.

Techniques disclosed herein relate to optical devices. Resins with different optical properties can be deposited in different areas to provide increased optical functionality. It can be difficult to design a single photopolymer material that meets several technical requirements. Different resins can be deposited on the same substrate to make a single film with spatially varying properties. Different resins can also be applied to different substrates in a stack. By using different resins, an optical component can be made that meets several technical requirements.

A label-free bio-aerosol sensing platform and method uses a field-portable and cost-effective device based on holographic microscopy and deep-learning, which screens bio-aerosols at a high throughput level. Two different deep neural networks are utilized to rapidly reconstruct the amplitude and phase images of the captured bio-aerosols, and to output particle information for each bio-aerosol that is imaged. This includes, a classification of the type or species of the particle, particle size, particle shape, particle thickness, or spatial feature(s) of the particle. The platform was validated using the label-free sensing of common bio-aerosol types, e.g., Bermuda grass pollen, oak tree pollen, ragweed pollen, Aspergillus spore, and Alternaria spore and achieved >94% classification accuracy. The label-free bio-aerosol platform, with its mobility and cost-effectiveness, will find several applications in indoor and outdoor air quality monitoring.

There are provided volume holograms and combinations of lenticular lenses and holograms in particular for security applications. In embodiments, a volume hologram comprises a holographic medium (102) including a first optical interference structure which, upon illumination, replays a first image (110); wherein the first image includes a lenticular lens layer (111) including an array of lenticules and a lenticular image layer (113) including first (114) and second (115) interlaced images corresponding with the array of lenticules.