Abstract: An optical element includes: a glass substrate; an optical function portion made of a resin; and a bonding portion that bonds the glass substrate and the optical function portion to each other. The bonding portion has a glass transition point of 85° C. or lower. The glass transition point of the bonding portion may be 50° C. or lower.

Abstract: An optical member includes a reflection-scattering unit that reflects and scatters light having a wavelength band which corresponds to at least a portion of a visible wavelength range, and transmits light having a wavelength band which corresponds to at least a portion of an infrared region, wherein rectilinear transmittance for the light having the wavelength band which corresponds to at least the portion of the infrared region is equal to or greater than 75%.

Abstract: An optical element includes: an optical function part; a flange disposed outside the optical function part; and a direction indication part in a part of the flange. A difference in level between the direction indication part and a flat surface of the flange is 2 ?m or less. The optical function part and a part of the flange may be covered with an antireflection film.

Abstract: The present invention relates to an optical element including an optical surface, a tapered part located on an outer peripheral side of the optical surface and having a normal line of which a direction heading to an outside of the optical element from an inside thereof, faces an optical axis side, and a side surface part located on an outer peripheral side of the tapered part, in which when a distance in a straight line vertical to an optical axis of from an end point on the optical axis side of the tapered part to the side surface part is denoted by A and a height of the tapered part based on the straight line is defined by B, in a cross section including the optical axis and passing through the tapered part, B/A is larger than 0.2.

Abstract: To provide a diffractive optical element having a high light utilization efficiency, whereby light spots having a predetermined pattern can be stably formed, a projection device and a measuring device.

Abstract: The present invention relates to a laminate in which a plurality of members including at least a glass are bonded via a bonding agent. The glass bonded has a chamfered portion in an end portion of a lamination surface of the glass, and the bonding agent adheres to the chamfered portion.

Abstract: An optical device includes a base material including a surface on which multiple concaves are formed. The concaves include respective curved surfaces. The concaves are formed so that the bottoms of the concaves are at two or more different positions in a depth direction. In the optical device, 2/7?|(n1?n2)×?d|/??10 holds, where n1 is the refractive index of the base material, n2 is the refractive index of a medium around the concaves, ? is the wavelength of a beam flux that enters the base material, and ?d is a range of the positions of the bottoms in the depth direction.

Abstract: A light guide element includes a light-guiding substrate and a diffraction part formed on a surface of the light-guiding substrate. The diffraction part includes an optical layer capable of exerting a diffractive action. The distance from the light-guiding substrate to a surface of the optical layer is equal to or less than 10% of a thickness of the light-guiding substrate. The light guide element satisfies |?D|?0.15 mm, where ?D is an amount of a change in D with the temperature change ?T, D [mm] is a distance, at the temperature T (° C.), between the center of the diffraction part and a position predetermined as a position where the ray of light comes out of the light-guiding substrate in a direction horizontal with respect to the light-guiding substrate, and ?T is a temperature change.

Abstract: To make it possible to emit a light pattern with a uniform light quantity within a detection surface in spite of 0th-order diffracted light included therein or to emit a light pattern for overall irradiation with a uniform light quantity distribution, without limiting a degree of freedom for design of the emitted light pattern. In a diffraction optical element according to the invention, a divergence angle converting function that is a function of converting the divergence angle of incident light due to diffraction effect and a light beam splitting function that is a function of splitting an incident light beam into a plurality of light beams due to diffraction effect are combined so that incident light as divergent light is split into a plurality of diffracted lights with different divergence angles from the divergence angle of the incident light and the diffracted lights is emitted.

Abstract: An image light projection screen has a plurality of aperiodic lens array units on a main surface. The aperiodic lens array units are arrayed two-dimensionally regularly and without any gap at least in an image display region. Each aperiodic lens array unit includes at least four apexes of micro-lenses each having a curved surface shape and arranged without any gap and non-periodically, and has symmetry keeping continuity of the curved surface shapes of the micro-lenses located in a boundary portion.

Abstract: An optical member includes a reflection-scattering unit that reflects and scatters light having a wavelength band which corresponds to at least a portion of a visible wavelength range, and transmits light having a wavelength band which corresponds to at least a portion of an infrared region, wherein rectilinear transmittance for the light having the wavelength band which corresponds to at least the portion of the infrared region is equal to or greater than 75%.

Abstract: An image light projection screen has a plurality of aperiodic lens array units on a main surface. The aperiodic lens array units are arrayed two-dimensionally regularly and without any gap at least in an image display region. Each aperiodic lens array unit includes at least four apexes of micro-lenses each having a curved surface shape and arranged without any gap and non-periodically, and has symmetry keeping continuity of the curved surface shapes of the micro-lenses located in a boundary portion.

Abstract: A light guide element includes a light-guiding substrate and a diffraction part formed on a surface of the light-guiding substrate. The diffraction part includes an optical layer capable of exerting a diffractive action. The distance from the light-guiding substrate to a surface of the optical layer is equal to or less than 10% of a thickness of the light-guiding substrate. The light guide element satisfies |?D|?0.15 mm, where ?D is an amount of a change in D with the temperature change ?T, D [mm] is a distance, at the temperature T (° C.), between the center of the diffraction part and a position predetermined as a position where the ray of light comes out of the light-guiding substrate in a direction horizontal with respect to the light-guiding substrate, and ?T is a temperature change.

Abstract: Disclosed are a diffractive optical element and a measurement device that are capable of reliably suppressing occurrence of a zero-order diffracted light beam and generating light spots in a wide range. The diffractive optical element has concave and convex portions and diffracts incident light in two dimensions to generate diffracted light. When a maximum diffraction angle with reference to an optical axis of the incident light is an angle range ?, the angle range ? is 7.5° or greater, and diffraction efficiency in a zero-order diffracted light beam is 5% or less.

Abstract: To make it possible to emit a light pattern with a uniform light quantity within a detection surface in spite of 0th-order diffracted light included therein or to emit a light pattern for overall irradiation with a uniform light quantity distribution, without limiting a degree of freedom for design of the emitted light pattern. In a diffraction optical element according to the invention, a divergence angle converting function that is a function of converting the divergence angle of incident light due to diffraction effect and a light beam splitting function that is a function of splitting an incident light beam into a plurality of light beams due to diffraction effect are combined so that incident light as divergent light is split into a plurality of diffracted lights with different divergence angles from the divergence angle of the incident light and the diffracted lights is emitted.

Abstract: An optical device includes a base material including a surface on which multiple concaves are formed. The concaves include respective curved surfaces. The concaves are formed so that the bottoms of the concaves are at two or more different positions in a depth direction. In the optical device, 2/7?|(n1?n2)×?d|/??10 holds, where n1 is the refractive index of the base material, n2 is the refractive index of a medium around the concaves, ? is the wavelength of a beam flux that enters the base material, and ?d is a range of the positions of the bottoms in the depth direction.

Abstract: A diffractive optical element includes first and second diffractive optical parts to generate diffracted lights two-dimensionally with respect to incident light. The diffracted lights generated by inputting the incident light to the first diffractive optical part are input to the second diffractive optical part in order to generate the diffracted lights from the second diffractive optical part, wherein ?1??2 and k1?k2 stand or, ?1??2 and k1?k2 stand among ?1 and ?2 denote diffraction angles of the first and second diffractive optical parts, and k1 and k2 denote numbers of light spots of the diffracted lights generated by the first and second diffractive optical parts.

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 diffractive optical element includes: a first diffractive element in which a plurality of basic units are two-dimensionally arranged; and a second diffractive element in which a plurality of basic units are two-dimensionally arranged, wherein when a direction in which the basic units are arranged in the first diffractive element is a first direction, a direction in which the basic units are arranged in the second diffractive element is a second direction, an angle ? between the first direction and the second direction is such that ?|?1|<?<|?1|, and ??0, sin ?1=??/?x where a closest distance of zero-order light generated when the diffracted light generated by the first diffractive element is further incident on the second diffractive element is ?x and a closest distance of the diffracted light and stray light generated by the second diffractive element is ?.

Abstract: To provide a diffractive optical element and a measuring device capable of generating light spots of dispersive type. The problem is resolved by providing a diffractive optical element having concaves and convexes and diffracting incident light in two dimensions so as to generate diffracted light, wherein when the number of a part of light spots formed by the diffracted light is denoted by n, an average distance W to the nearest neighbor in the light spots normalized by an area of a region onto which the light spots are projected falls within a range of 1/(2×n1/2)<W<1/(n1/2).