Abstract: A cell culture container has a bottom face and a surface having a dent-formed region having a plurality of dents with an average depth of 200 ?m or more, the formula ?1<90??2+sin?1{sin(?2)×1.38/n} is satisfied wherein ?1 (deg) is the angle formed by a first tangent line which passes a connecting point of a first curved line corresponding to a first dent and a second curved line corresponding to a second dent and which is in contact with the first curved line, and a base line which passes the connecting point and which is in parallel with the bottom face, and n is the refractive index of the substrate, and the formula ?2<90??1+sin?1 {sin(?1)×1.38/n} is satisfied wherein ?2 (deg) is the angle formed by a second tangent line which passes the connecting point and which is in contact with the second curved line, and the base line.

Abstract: A diffusion plate includes: a glass substrate having a first main surface and a second main surface opposite to the first main surface; and a lens array formed on the first main surface of the glass substrate, wherein, when the first main surface of the glass substrate is viewed in a plan view, the glass substrate and the lens array each have a donut shape, the lens array includes a plurality of lenses, and the first main surface of the glass substrate has an annular first flat surface having a width equal to or more than 1.0 mm between an inner periphery of the glass substrate and an inner periphery of the lens array, or has an annular second flat surface having a width equal to or more than 1.0 mm between an outer periphery of the glass substrate and an outer periphery of the lens array.

Abstract: A balloon catheter has excellent pressure resistance and operability by being thinned while suppressing a decrease in pressure resistance strength accompanying an increase in diameter of the balloon. The balloon of the balloon catheter includes at least an inner layer and an outer layer, has an area draw-down ratio (ADDR) of 2.91 or more and 2.97 or less, the area draw-down ratio (ADDR) being determined by a ratio of the cross-sectional area of a tubular parison disposed in a mold and blow-molded in a balloon shape to a cross-sectional area of the balloon after blow molding, and has a layer provided outside the inner layer and having an elongation rate at a breaking point lower than the elongation rate at a breaking point of the inner layer.

Abstract: A diffractive optical element includes a unit structure periodically arranged in a first direction and configured to diffract incident light in the first direction. The diffractive optical element has a phase pattern designed such that an angular separation between an outermost diffracted light beam and a second-outermost diffracted light beam along the first direction is smaller than the divergence angle of the incident light.

Abstract: A diffractive optical element includes: a diffraction unit; and a lens unit disposed on a light incident side of the diffraction unit. The lens unit includes: a substrate; and a protrusion and recess portion disposed on a side opposite to a light incident side of the substrate. The protrusion and recess portion includes: a periodic structure of a relief-protrusion portion disposed in a central part, a periodic structure of a stepwise grating disposed in a central part simulating the relief-protrusion portion, or a combination thereof; and a grating disposed in a portion other than the central part. The number of steps of the stepwise grating disposed in the central part is larger than the number of steps of the grating disposed in the portion other than the central part.

Abstract: A method for processing into an aspheric lens, includes: a preprocessing step of performing preprocessing on a glass substrate; and an etching step of performing wet etching on the glass substrate subjected to the preprocessing. The preprocessing step includes a step of irradiating a certain position of the glass substrate with a pulsed laser beam such that a partial region inside the glass substrate is modified, thereby generating a density distribution in a thickness direction at the position irradiated with the pulsed laser beam, or a step of forming a predetermined wedge-shaped concave portion in a surface of the glass substrate by use of a chemical or physical processing method.

Abstract: To provide a substrate of a cell culture container in which cells are appropriately maintained in dents and the cells in the dents are appropriately observed, and a cell culture container. The substrate of a cell culture container of the present invention has a bottom face and a surface having a dent-formed region having a plurality of dents formed, wherein the average depth of the plurality of dents is 200 µm or more, the formula ?1<90-?2+sin-1{sin(?2)×1.38/n} is satisfied wherein ?1 (deg) is the angle formed by a first tangent line which passes a connecting point of a first curved line corresponding to a first dent and a second curved line corresponding to a second dent and which is in contact with the first curved line, and a base line which passes the connecting point and which is in parallel with the bottom face, and n is the refractive index of the substrate, and the formula ?2<90-?1+sin-1{sin(?1)×1.

Abstract: A homogenizer includes a convex-lens array pair including a first convex-lens array disposed on a light entrance side and a second convex-lens array disposed on a light emission side. The first convex-lens array and the second convex-lens array are disposed so as to face each other such that each of the convex-lens arrays has a lens surface opposed to each other outward or inward. The first convex-lens array includes a plurality of first convex lenses in an array arrangement. The second convex-lens array includes a plurality of second convex lenses in an array arrangement. The first convex lens has an average internal transmission angle for incident light entering a lens-surface center region in the lens cross-section and being in parallel with the symmetry axis being equal to or more than 1.3 times an average internal transmission angle of a spherical convex lens.

Abstract: A diffractive optical element includes a unit structure periodically arranged in a first direction and configured to diffract incident light in the first direction. The diffractive optical element has a phase pattern designed such that an angular separation between an outermost diffracted light beam and a second-outermost diffracted light beam along the first direction is smaller than the divergence angle of the incident light.

Abstract: A diffractive optical element includes: a diffraction unit; and a lens unit disposed on a light incident side of the diffraction unit. The lens unit includes: a substrate; and a protrusion and recess portion disposed on a side opposite to a light incident side of the substrate. The protrusion and recess portion includes: a periodic structure of a relief-protrusion portion disposed in a central part, a periodic structure of a stepwise grating disposed in a central part simulating the relief-protrusion portion, or a combination thereof; and a grating disposed in a portion other than the central part. The number of steps of the stepwise grating disposed in the central part is larger than the number of steps of the grating disposed in the portion other than the central part.

Abstract: A homogenizer includes a convex-lens array pair including a first convex-lens array disposed on a light entrance side and a second convex-lens array disposed on a light emission side. The first convex-lens array and the second convex-lens array are disposed so as to face each other such that each of the convex-lens arrays has a lens surface opposed to each other outward or inward. The first convex-lens array includes a plurality of first convex lenses in an array arrangement. The second convex-lens array includes a plurality of second convex lenses in an array arrangement. The first convex lens has an average internal transmission angle for incident light entering a lens-surface center region in the lens cross-section and being in parallel with the symmetry axis being equal to or more than 1.3 times an average internal transmission angle of a spherical convex lens.

Abstract: A method for processing into an aspheric lens, includes: a preprocessing step of performing preprocessing on a glass substrate; and an etching step of performing wet etching on the glass substrate subjected to the preprocessing. The preprocessing step includes a step of irradiating a certain position of the glass substrate with a pulsed laser beam such that a partial region inside the glass substrate is modified, thereby generating a density distribution in a thickness direction at the position irradiated with the pulsed laser beam, or a step of forming a predetermined wedge-shaped concave portion in a surface of the glass substrate by use of a chemical or physical processing method.

Abstract: To provide a diffractive optical element which is thin and is capable of emitting light in a wide range while further reducing zeroth order light. The diffractive optical element of the present invention comprises a substrate, a convexo-concave portion formed on one surface of the substrate and having a predetermined diffraction function to incident light, and an antireflection layer formed between the substrate and the convexo-concave portion, wherein the difference in the refractive index in a wavelength band of the incident light between a first medium constituting convex portions of the convexo-concave portion and a second medium constituting concave portions of the convexo-concave portion is at least 0.70, and when the incident light enters from a normal direction of the substrate, an emergent angle range which is an angle range representing spread of a light pattern formed by the diffracted light emerging from the convexo-concave portion, is at least 60°.

Abstract: An optical element in which transmittance of light monotonically decreases from a center portion toward a peripheral portion, the optical element includes an absorbing material portion made of a material that absorbs a part of light and formed such that its thickness monotonically increases from the center portion toward the peripheral portion; and a transparent material portion made of a material that transmits light and is stacked on the absorbing material portion, a total thickness of the absorbing material portion and the transparent material portion being substantially constant.

Abstract: An optical element in which transmittance of light monotonically decreases from a center portion toward a peripheral portion, includes a light absorbing portion, made of a material that absorbs a part of or all of visible light, formed at one surface of a transparent substrate such that its thickness monotonically increases from the center portion toward the peripheral portion; a light transmitting portion, made of a material that transmits visible light, formed on the light absorbing portion; and a transparent resin layer, made of a material that transmits visible light, formed at another surface of the transparent substrate, wherein each of the light absorbing portion, the light transmitting portion and the transparent resin layer is made of a resin material.

Abstract: An optical element in which transmittance of light monotonically decreases from a center portion toward a peripheral portion, includes a light absorbing portion, made of a material that absorbs a part of or all of visible light, formed at one surface of a transparent substrate such that its thickness monotonically increases from the center portion toward the peripheral portion; a light transmitting portion, made of a material that transmits visible light, formed on the light absorbing portion; and a transparent resin layer, made of a material that transmits visible light, formed at another surface of the transparent substrate, wherein each of the light absorbing portion, the light transmitting portion and the transparent resin layer is made of a resin material.

Abstract: An optical element in which transmittance of light monotonically decreases from a center portion toward a peripheral portion, the optical element includes an absorbing material portion made of a material that absorbs a part of light and formed such that its thickness monotonically increases from the center portion toward the peripheral portion; and a transparent material portion made of a material that transmits light and is stacked on the absorbing material portion, a total thickness of the absorbing material portion and the transparent material portion being substantially constant.

Abstract: An optical device for monotonously reducing light transmittance from a center portion thereof to a peripheral portion thereof. The optical device includes an absorbing material part formed of a material that can absorb light and having a thickness monotonously increasing from the center portion to the peripheral portion, and a transparent material part formed of a material that can transmit light and stacked on the absorbing material part. A value of a refractive index of the absorbing material part and a value of a refractive index of the transparent material part are different.

Abstract: A composite optical element includes: a single lens; a first resin layer formed on a surface of the single lens; a second resin layer formed on the first resin layer, wherein: the first resin layer has a diffraction grating of a Fresnel lens configuration; and a refractive index of the first resin layer and that of the second layer are substantially the same value for at least a light beam of one of a light beam of a wavelength ?1, a light beam of a wavelength ?2 and a light beam of a wavelength ?3 (?1<?2<?3), and the refractive index of the first resin layer and that of the second resin layer are different values for at least a light beam of another one of the light beam of the wavelength ?1, the light beam of the wavelength ?2 and the light beam of the wavelength ?3.