A camera system includes an image sensor assembly and a tunable optical element. The tunable optical element is a polymer dispersed liquid crystal lens doublet using a PDLC layer. The doublet is tunable by applying an electric field to the optical element via a control element. The control element applies a voltage differential to the optical element inducing an electric field which changes the polarization of the PDLC within the optical element. The refractive index of the lens doublet is dependent on the polarization of the liquid crystals within the optical element. Applying the electric field to the tunable element changes the optical properties of the lens doublet.

A camera system includes an image sensor assembly and a tunable optical element. The tunable optical element is a holographic polymer dispersed liquid crystal diffraction grating of alternating PDLC layers. The diffraction grating is tunable by applying an electric field to the optical element via a control element. The control element applies a voltage differential to the optical element inducing an electric field which changes the polarization of the PDLC within the optical element. The refractive index of the holographic grating is dependent on the polarization of the liquid crystals within the optical element. Applying the electric field to the tunable element changes the optical properties of the grating.

A camera system includes an image sensor assembly and a tunable optical element. The tunable optical element is a polymer dispersed liquid crystal lens doublet using a PDLC layer. The doublet is tunable by applying an electric field to the optical element via a control element. The control element applies a voltage differential to the optical element inducing an electric field which changes the polarization of the PDLC within the optical element. The refractive index of the lens doublet is dependent on the polarization of the liquid crystals within the optical element. Applying the electric field to the tunable element changes the optical properties of the lens doublet.

A camera system includes an image sensor assembly and a tunable optical element. The tunable optical element is a gradient index (GRIN) lens created from a polymer dispersed liquid crystal and a coupled control element. The GRIN lens is tunable by applying an electric field to the optical element via a control element. The control element applies a voltage differential to the optical element inducing an electric field which changes the polarization of the PDLC within the optical element. The electrodes of the control element can include sheet resistors with a radially dependent voltage drop. The refractive index of the GRIN lens is dependent on the polarization of the liquid crystals within the optical element. Applying the electric field to the tunable element changes the optical properties of the grating.

A camera system includes an image sensor assembly and a tunable optical element. The tunable optical element is a doublet prism including one polymer dispersed liquid crystal layer. The doublet prism is tunable by applying an electric field to the optical element via a control element. The control element applies a voltage differential to the optical element inducing an electric field which changes the polarization of the PDLC within the optical element. The refractive index of the doublet prism is dependent on the polarization of the liquid crystals within the optical element. Applying the electric field to the tunable element changes the optical properties of the doublet prism.

A camera system includes an image sensor assembly and a tunable optical element. The tunable optical element is a polymer dispersed liquid crystal gradient index (GRIN) prism. The GRIN prism is tunable by applying an electric field to the optical element via a control element. The control element applies a voltage differential to the optical element inducing an electric field which changes the polarization of the PDLC within the optical element. The control element can include a sheet resistor that has a linearly dependent voltage drop. The refractive index of the GRIN prism is dependent on the polarization of the liquid crystals within the optical element. Applying the electric field to the tunable element changes the optical properties of the GRIN prism.

A hologram recording composition includes at least: a photopolymerizable compound containing at least a first photopolymerizable monomer; binder resin that is inactive to photopolymerization; and a photopolymerization initiator. A change in polarity of the first photopolymerizable monomer by photopolymerization reduces compatibility with the binder resin of the photopolymerizable compound than that before polymerization, the compatibility of the photopolymerizable compound before the polymerization being high.

Gratings may be used in waveguides. Deep surface relief gratings (SRGs) may offer many advantages over conventional SRGs, an important one being a higher S-diffraction efficiency. Deep SRGs can be implemented as polymer surface relief gratings or evacuated periodic structures (EPSs). EPSs can be formed by first recording a holographic polymer dispersed liquid crystal (HPDLC) periodic structure. Removing the liquid crystal from the cured periodic structure provides a polymer surface relief grating. Polymer surface relief gratings have many applications including for use in waveguide-based displays.

Techniques disclosed herein relate to photo-patternable latent-chemistry inorganic materials. An example of the photo-patternable latent-chemistry inorganic materials includes a sol-gel material comprising a solution containing a tin dichloride salt, at least one alcohol containing solvent, and optionally a photo-acid generator or photo-acid. The sol-gel material, upon selective photo-excitation (which forms a latent pattern with latent chemistry in the sol-gel material) and blanket thermal annealing, can form a coating having a formula SnO(n)X(m), where the n:m ratio and/or n-m values of the coating vary across regions of the coating, such that a refractive index of the coating varies across regions of the coating, without affecting the coating's transparency for visible light.

The present invention is to provide: a photosensitive composition for volume hologram recording and a photosensitive substrate for volume hologram recording, which provide increased sensitivity during hologram recording and a high refractive index modulation amount, and which do not inhibit the decolorization of the sensitizing dye; and a volume hologram recorded medium which provides high-luminance hologram images with increased productivity. Disclosed is a photosensitive composition for volume hologram recording, comprising: a photopolymerizable monomer, a photopolymerization initiator, a sensitizing dye for sensitizing the photopolymerization initiator, a binder resin, and a thiol group-containing compound, wherein the photopolymerizable monomer contains a photoradically polymerizable monomer and a photocationically polymerizable monomer; wherein the thiol group-containing compound is a chain transfer agent for the photoradically polymerizable monomer and is a polyfunctional secondary thiol compound having two or more secondary thiol groups per molecule; and wherein the content of the thiol group-containing compound is 1.5 to 30 parts by mass with respect to 100 parts by mass of the photoradically polymerizable monomer.