Abstract: A light guide element includes a light guide substrate that is a single-layer light guide substrate; and a diffraction layer formed on the light guide substrate. The diffraction layer includes a first diffraction grating configured to in-couple light into the light guide substrate; and a second diffraction grating configured to outcouple totally internally reflected light having propagated in the light guide substrate out of the light guide substrate. The first diffraction grating in-couples the incident light in a range of 60 degrees or more including a direction normal to substrate, for at least one of first wavelength of 450 nm±20 nm, second wavelength of 530 nm±20 nm, and third wavelength of 630 nm±20 nm. The second diffraction grating outcouples the totally internally reflected light in a range of 60 degrees or more including the direction normal to substrate, for at least one of the first, second, and third wavelengths.

Abstract: The present invention relates to an optical filter, a solid-state imaging element and an imaging device lens which contain a near infrared ray absorbing layer having a specific near infrared ray absorbing dye dispersed in a transparent resin having a refractive index of 1.54 or more, and also relates to an imaging device containing the solid-state imaging element or the imaging device lens. The near infrared ray absorbing layer has a transmittance of visible light of from 450 to 600 nm of 70% or more, a transmittance of light in a wavelength region of from 695 to 720 nm of not more than 10%, and an amount of change of transmittance of not more than ?0.8.

Abstract: The present invention relates to a microlens array comprising a transparent substrate, a resin layer provided on/above at least one surface of the transparent substrate, containing a photosensitive resin and forming a plurality of microlenses, and a functional layer reflecting at least light for reacting the photosensitive resin, the functional layer is formed on a surface of the transparent substrate at a side on which the resin layer is not formed, or on the surface of the transparent substrate at the side on which the resin layer is formed and at a position nearer the transparent substrate than the resin layer.

Abstract: The present invention relates to an optical filter, a solid-state imaging element and an imaging device lens which contain a near infrared ray absorbing layer having a specific near infrared ray absorbing dye dispersed in a transparent resin having a refractive index of 1.54 or more, and also relates to an imaging device containing the solid-state imaging element or the imaging device lens. The near infrared ray absorbing layer has a transmittance of visible light of from 450 to 600 nm of 70% or more, a transmittance of light in a wavelength region of from 695 to 720 nm of not more than 10%, and an amount of change of transmittance of not more than ?0.8.

Abstract: An optical member has: a transparent substrate; and a dielectric multilayer on the transparent substrate formed by stacking a plurality of unit refractive index layers each formed of a high-refractive index layer having a refractive index of 2 or more and a low-refractive index layer having a refractive index of 1.6 or less. In the optical member, a total number of the unit refractive index layers is 15 or more, and a number of the unit refractive index layers satisfying a condition of nHdH/nLdL?3 is 10 or more, nHdH represents an optical thickness of the high-refractive index layer, and nLdL represents an optical thickness of the low-refractive index layer.

Abstract: Disclosed is an optical member in the form of a film or a thin plate. The optical member contains near infrared absorbing particles comprising crystallites of an oxide containing at least Cu and P and having a number average aggregated particle size of at least 20 nm and at most 200 nm. Further, a near infrared cut filter, a solid-state imaging element, a lens for an imaging device and an imaging/display device are disclosed. They comprise a near infrared absorbing layer containing near infrared absorbing particles comprising crystallites of an oxide containing at least Cu and P and having a number average aggregated particle size of at least 20 nm and at most 200 nm.

Abstract: The present invention relates to an optical filter, a solid-state imaging element and an imaging device lens which contain a near infrared ray absorbing layer having a specific near infrared ray absorbing dye dispersed in a transparent resin having a refractive index of 1.54 or more, and also relates to an imaging device containing the solid-state imaging element or the imaging device lens. The near infrared ray absorbing layer has a transmittance of visible light of from 450 to 600 nm of 70% or more, a transmittance of light in a wavelength region of from 695 to 720 nm of not more than 10%, and an amount of change of transmittance of not more than ?0.8.

Abstract: The present invention relates to a microlens array comprising a transparent substrate, a resin layer provided on/above at least one surface of the transparent substrate, containing a photosensitive resin and forming a plurality of microlenses, and a functional layer reflecting at least light for reacting the photosensitive resin, the functional layer is formed on a surface of the transparent substrate at a side on which the resin layer is not formed, or on the surface of the transparent substrate at the side on which the resin layer is formed and at a position nearer the transparent substrate than the resin layer.

Abstract: An optical element includes an optical member made of a material that transmits light; a high refractive index layer and a low refractive index layer that are stacked on a front surface of the optical member; and a surface protection layer that is formed on an upper most layer among the high refractive index layer and the low refractive index layer, the surface protection layer being made of a material including one of a mixed oxide of Si and Sn, a mixed oxide of Si and Zr, and a mixed oxide of Si and Al, and the refraction index of the surface protection layer being less than or equal to the refraction index of the high refractive index layer and greater than or equal to the refraction index of the low refractive index layer.

Abstract: A microlens array to be used in combination with a pixel array of an imaging element. The microlens includes a glass substrate; and a plurality of microlenses provided on at least one surface of the glass substrate and arranged in an array shape. Each of the plurality of the microlenses is constituted such that light to be entered into the microlens is received by a plurality of pixels of the imaging element. A difference between a coefficient of linear expansion of the glass substrate and a coefficient of linear expansion of an imaging element substrate having the pixel array formed thereon or member of a package to be bonded to the imaging element substrate is within 8×10?6 (/K).

Abstract: An optical member has: a transparent substrate; and a dielectric multilayer on the transparent substrate formed by stacking a plurality of unit refractive index layers each formed of a high-refractive index layer having a refractive index of 2 or more and a low-refractive index layer having a refractive index of 1.6 or less. In the optical member, a total number of the unit refractive index layers is 15 or more, and a number of the unit refractive index layers satisfying a condition of nHdH/nLdL?3 is 10 or more, nHdH represents an optical thickness of the high-refractive index layer, and nLdL represents an optical thickness of the low-refractive index layer.

Abstract: The present invention relates to an optical filter, a solid-state imaging element and an imaging device lens which contain a near infrared ray absorbing layer having a specific near infrared ray absorbing dye dispersed in a transparent resin having a refractive index of 1.54 or more, and also relates to an imaging device containing the solid-state imaging element or the imaging device lens. The near infrared ray absorbing layer has a transmittance of visible light of from 450 to 600 nm of 70% or more, a transmittance of light in a wavelength region of from 695 to 720 nm of not more than 10%, and an amount of change of transmittance of not more than ?0.

Abstract: To provide near-infrared-absorbing particles which have a high transmittance in the visible light region and a low transmittance in the near infrared region and which, when incorporated, can give a near-infrared-absorbing coating film wherein the transmittance sharply changes in the wavelength range of from 630 to 700 nm; a process for their production; and their dispersion. Near-infrared-absorbing particles consisting essentially of crystallites of A1/nCuPO4 and having a number average aggregated particle size is from 20 to 200 nm, wherein A is at least one member selected from the group consisting of alkali metals (Li, Na, K, Rb and Cs), alkaline earth metals (Mg, Ca, Sr and Ba) and NH4, and n is 1 when A is an alkali metal or NH4, or 2 when A is an alkaline earth metal.

Abstract: Disclosed is an optical member in the form of a film or a thin plate. The optical member contains near infrared absorbing particles comprising crystallites of an oxide containing at least Cu and P and having a number average aggregated particle size of at least 20 nm and at most 200 nm. Further, a near infrared cut filter, a solid-state imaging element, a lens for an imaging device and an imaging/display device are disclosed. They comprise a near infrared absorbing layer containing near infrared absorbing particles comprising crystallites of an oxide containing at least Cu and P and having a number average aggregated particle size of at least 20 nm and at most 200 nm.

Abstract: To provide near-infrared-absorbing particles which have a high transmittance in the visible light region and a low transmittance in the near infrared region and which, when incorporated, can give a near-infrared-absorbing coating film wherein the transmittance sharply changes in the wavelength range of from 630 to 700 nm; a process for their production; and their dispersion. Near-infrared-absorbing particles consisting essentially of crystallites of A1/nCuPO4 and having a number average aggregated particle size is from 20 to 200 nm, wherein A is at least one member selected from the group consisting of alkali metals (Li, Na, K, Rb and Cs), alkaline earth metals (Mg, Ca, Sr and Ba) and NH4, and n is 1 when A is an alkali metal or NH4, or 2 when A is an alkaline earth metal.

Abstract: A projection type display device includes: a light emitting unit that includes at least one light source for emitting a coherent light. An image light generating unit modulates the light emitted by the light emitting unit to generate an image light. A projecting unit projects the image light. A phase modulating unit is arranged either between the light emitting unit and the image light generating unit or between the image light generating unit and the projecting unit and has an area where at least one of a retardation value and an azimuth direction of a slow axis is distributed respectively in different directions or values in a plane orthogonal to an optical axis.

Abstract: A liquid crystal diffraction lens element and an optical head device, which can switch focal lengths of both of outgoing light and returning light by a single element, are provided. The liquid crystal lens element comprises transparent substrates 1a, 1b, a liquid crystal 4 sandwiched between the transparent substrates 1a, 1b, transparent electrodes 2a, 2b, birefringent Fresnel lens members 3a, 3b each having a Fresnel lens shape and made of a birefringent material, and a seal 5, wherein the extraordinary refractive index direction A of the birefringent Fresnel lens member 3a and the extraordinary refractive index direction B of the birefringent Fresnel lens member 3b are perpendicular to each other, and the alignment direction of the liquid crystal 4 at the interface between the liquid crystal 4 and the transparent substrate 1a is perpendicular to the alignment direction of the liquid crystal 4 at the interface between the liquid crystal 4 and the transparent substrate 1b.

Abstract: A projection type display device includes: a light emitting unit that includes at least one light source for emitting a coherent light. An image light generating unit modulates the light emitted by the light emitting unit to generate an image light. A projecting unit projects the image light. A phase modulating unit is arranged either between the light emitting unit and the image light generating unit or between the image light generating unit and the projecting unit and has an area where at least one of a retardation value and an azimuth direction of a slow axis is distributed respectively in different directions or values in a plane orthogonal to an optical axis.

Abstract: A liquid crystal diffraction lens element and an optical head device, which can switch focal lengths of both of outgoing light and returning light by a single element, are provided. The liquid crystal lens element comprises transparent substrates 1a, 1b, a liquid crystal 4 sandwiched between the transparent substrates 1a, 1b, transparent electrodes 2a, 2b, birefringent Fresnel lens members 3a, 3b each having a Fresnel lens shape and made of a birefringent material, and a seal 5, wherein the extraordinary refractive index direction A of the birefringent Fresnel lens member 3a and the extraordinary refractive index direction B of the birefringent Fresnel lens member 3b are perpendicular to each other, and the alignment direction of the liquid crystal 4 at the interface between the liquid crystal 4 and the transparent substrate 1a is perpendicular to the alignment direction of the liquid crystal 4 at the interface between the liquid crystal 4 and the transparent substrate 1b.

Abstract: The present invention provides an optical attenuator reducing variations in optical attenuation amount in response to temperature change, and an optical head device having properties excellent in recording and reproducing an information. An optical attenuator comprising a liquid crystal element having spirally arranged molecules in which a liquid crystal layer 107 is sandwiched between transparent electrodes 103 and 104, and a polarizing beam splitter 110 whose transmittance is changed depending on a polarization state, wherein the ordinary refractive index (no) and the extraordinary refractive index (ne) of liquid crystal, the angle (?pt) of liquid crystal molecules against the transparent substrate surfaces, the thickness (d) of the liquid crystal layer 107 and the wavelength (?) of incident light, constituent elements are configured so that the value A satisfies the range of from 0.5 to 1.