A device is provided. The device includes a first polarization hologram element configured to operate as a half-wave plate for a first light having a first wavelength, and as a full-wave plate for a second light having a second wavelength. The device also includes a second polarization hologram element stacked with the first polarization hologram, and configured to operate as the half-wave plate for the second light and as the full-wave plate for the first light. The first polarization hologram element is configured to forwardly diffract or transmit the first light depending on a handedness of the first light. The second polarization hologram element is configured to forwardly diffract or transmit the second light depending on a handedness of the second light.

A display system comprising a first plurality of pixels, a second plurality of pixels, a first Fourier transform lens and a second Fourier transform lens. The first plurality of pixels is arranged ranged to display first holographic data corresponding to a first holographic reconstruction and receive light of a first wavelength. The a second plurality of pixels is arranged to display second holographic data corresponding to a second holographic reconstruction and receive light of a second wavelength. The first Fourier transform lens is arranged to receive spatially modulated light having a first wavelength from the first plurality of pixels and perform an optical Fourier transform of the received light to form the first holographic reconstruction at a replay plane, wherein the first holographic reconstruction is formed of light at the first wavelength. The second Fourier transform lens is arranged to receive spatially modulated light having a second wavelength from the second plurality of pixels and perform an optical Fourier transform of the received light to form the second holographic reconstruction at the replay plane, wherein the second holographic reconstruction is formed of light at the second wavelength. The optical path length from the first Fourier transform lens to the replay plane is not equal to the optical path length from the second Fourier transform lens to the replay plane.

A display system comprising a first plurality of pixels, a second plurality of pixels, a first Fourier transform lens and a second Fourier transform lens. The first plurality of pixels is arranged ranged to display first holographic data corresponding to a first holographic reconstruction and receive light of a first wavelength. The a second plurality of pixels is arranged to display second holographic data corresponding to a second holographic reconstruction and receive light of a second wavelength. The first Fourier transform lens is arranged to receive spatially modulated light having a first wavelength from the first plurality of pixels and perform an optical Fourier transform of the received light to form the first holographic reconstruction at a replay plane, wherein the first holographic reconstruction is formed of light at the first wavelength. The second Fourier transform lens is arranged to receive spatially modulated light having a second wavelength from the second plurality of pixels and perform an optical Fourier transform of the received light to form the second holographic reconstruction at the replay plane, wherein the second holographic reconstruction is formed of light at the second wavelength. The optical path length from the first Fourier transform lens to the replay plane is not equal to the optical path length from the second Fourier transform lens to the replay plane.

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.

Disclosed are systems and methods for manufacturing energy directing systems for directing energy of multiple energy domains. Energy relays and energy waveguides are disclosed for directing energy of multiple energy domains, including electromagnetic energy, acoustic energy, and haptic energy. Systems are disclosed for projecting and sensing 4D energy-fields comprising multiple energy domains.

Disclosed are systems and methods for manufacturing energy directing systems for directing energy of multiple energy domains. Energy relays and energy waveguides are disclosed for directing energy of multiple energy domains, including electromagnetic energy, acoustic energy, and haptic energy. Systems are disclosed for projecting and sensing 4D energy-fields comprising multiple energy domains.

A method of fabricating a component (1) comprises the steps of providing precursor material in a working medium, creating acoustic forces and positioning the precursor material in the working medium under the effect of the acoustic forces, so that a material distribution is formed, which has a shape of the component to be fabricated, and subjecting at least one of the material distribution and the working medium to a fixation, so that the precursor material of the material distribution or the working medium surrounding the material distribution is bound, wherein the step of creating the acoustic forces includes generating an acoustic interference pattern (5), and the material distribution (4) is formed by moving the precursor material (2) towards energy extrema of the acoustic interference pattern (5). Furthermore, an apparatus (100) for fabricating a component (1) is described.

A holographic projector having an optical path is described. The holographic projector comprises a first spatial light modulator arranged to display a first hologram, and a first light source. The first light source is arranged to illuminate the first spatial light modulator with light of a first wavelength such that a first holographic reconstruction corresponding to the first hologram is formed on a replay plane. The holographic projector further comprises a continuous block of transparent material. At least part of the optical path is formed through the continuous block of transparent material. The transparent material has a refractive index greater than air.

A holographic recording medium composition comprising component (e): a compound having an isocyanate group or an isocyanate-reactive functional group and further having a nitroxyl radical group, wherein component (e) contains component (e-1) below: component (e-1): a compound having a heterobicyclic ring structure or a heterotricyclic ring structure, the heterobicyclic ring structure or the heterotricyclic ring structure being obtained by replacing a carbon atom in a bicyclic ring structure or a tricyclic ring structure by the nitroxyl radical group.

A holographic recording medium composition comprising component (e): a compound having an isocyanate group or an isocyanate-reactive functional group and further having a nitroxyl radical group, wherein component (e) contains component (e-1) below: component (e-1): a compound having a heterobicyclic ring structure or a heterotricyclic ring structure, the heterobicyclic ring structure or the heterotricyclic ring structure being obtained by replacing a carbon atom in a bicyclic ring structure or a tricyclic ring structure by the nitroxyl radical group.