Abstract: A display device for displaying a floating aerial image using retroreflection includes a light source, a beam splitter, at least first and second retroreflection members disposed along different planes, and at least first and second phase plates disposed on respective surfaces of the first retroreflection member and the second retroreflection member, wherein the beam splitter is configured to reflect light from the light source to the first and second retroreflection members, and to transmit light reflected by the first and second retroreflection members so as to form the floating aerial image, and a slow axis of the first phase plate has an angle difference with respect to a slow axis of the second phase plate such that a difference between a phase difference of the light transmitted through the first phase plate and a phase difference of the light transmitted through the second phase plate becomes small.

Abstract: A display apparatus is configured to display an aerial image by using retroreflection. The display apparatus includes a light source; a beam splitter configured to reflect light output from the light source; and a plurality of retroreflective materials configured to reflect light from the beam splitter in a same direction as incident light. The plurality of retroreflective materials include at least three retroreflective materials that are arranged in a range where the aerial image can be observed, and the plurality of retroreflective materials are in a positional relationship such that at least one side of each of the retroreflective materials is overlapping with a side of an adjacent retroreflective material.

Abstract: A method for manufacturing an optical element includes forming an optical element unit comprised of an optical material such as glass and having an outer shape of a regular triangle or a regular hexagon, arranging a plurality of optical element units two-dimensionally on a substrate so as to have a structure imitating a molecular structure of graphene or a carbon nanotube, and processing the substrate on which the plurality of optical element units are mounted into a desired surface shape.

Abstract: A display device configured for displaying an aerial image by using retro-reflection is provided. The display device includes: a light source disposed being inclined to one side of a reference line; a retroreflective member disposed being inclined to another side of the reference line; a polarized-beam splitter disposed to face the light source and the retroreflective member; and a transmission film formed on the polarized-beam splitter. The transmission film includes a low transmittance area in which the light source is difficult to be seen in an observation range where the aerial image is visible.

Abstract: A display device capable of displaying an aerial image by using retroreflection includes a light source, a diffusion plate arranged over the light source, a first polarizing plate arranged over the diffusion plate, a second polarizing plate arranged over the first polarizing plate, a retroreflecting member arranged on the second polarizing plate and having a design for generating an original image by irradiation of the light source, and a polarizing beam splitter arranged to face the retroreflecting member. The first polarizing plate includes a region inclined with respect to a main surface of the second polarizing plate.

Abstract: There is provided an imaging lens with excellent optical characteristics while satisfying demand of wide field of view. An imaging lens comprises, in order from an object side to an image side, a first lens with negative refractive power in a paraxial region, a second lens with positive or negative refractive power having an object-side surface being concave in a paraxial region, a third lens with positive refractive power having a biconvex shape with convex surfaces on the object side and the image side in a paraxial region, and a fourth lens with positive refractive power having an image-side surface being convex in a paraxial region, and predetermined conditional expressions are satisfied.

Abstract: A display device capable of displaying an aerial image by using retroreflection, the display device includes: an optical member configured to transmit a part of incident light and to reflect the rest; a retroreflective member which is arranged so as to face the optical member and having a notch or an opening for generating a design of an original image of an aerial image; a light source configured to illuminate the retroreflective member from a back surface side; and a transparent intermediate layer that is arranged between the optical member and the retroreflective member having a material with a refractive index of less than 1.

Abstract: A display device for displaying an aerial image using retro-reflection includes: an optical member configured to separate incident light into reflected light and transmitted light; a retro-reflective member positioned to face the optical member and having a cutout or an opening that features a design; a light source positioned on a backside of the retro-reflective member; and a transparent member made of a substance with a refractive index greater than 1, and positioned between the optical member and the retro-reflective member.

Abstract: An imaging device that is capable of causing a change in an aerial image, and can be reduced in size is provided. The imaging device includes, in a housing, a disk-shaped retro-reflection sheet in which a plurality of designs are formed at different positions, an LED light source configured to irradiate the retro-reflection sheet, a beam splitter, and a motor configured to rotate and move the retro-reflection sheet. The retro-reflection sheet is rotated and moved to enable switching of aerial images of the designs irradiated by the LED light source.

Abstract: A display device, which is capable of displaying an aerial image using retroreflection, includes a plurality of light sources, an optical member, and a retroreflection member. The plurality of light sources are configured to output identical images in mutually different directions. The optical member splits incident light into reflected light and transmitted light at a predetermined ratio. The retroreflection member is configured to provide a retroreflection plane in a range of approximately 180 degrees with respect to a principal plane of the optical member. Light of the identical images output from the plurality of light sources is incident on the retroreflection member via the optical member, and the light reflected by the retroreflection member is transmitted through the optical member, thereby displaying a plurality of aerial images corresponding to the identical images output by the plurality of light sources.

Abstract: There is provided an imaging lens with excellent optical characteristics which satisfies demand of low profile and low F-number. An imaging lens comprising in order from an object side to an image side, a first lens with positive refractive power having an object-side surface being convex in a paraxial region, a second lens with negative refractive power having an object-side surface being convex in a paraxial region, a third lens with positive or negative refractive power in a paraxial region, a fourth lens with negative refractive power in a paraxial region, and a fifth lens with positive refractive power having an image-side surface being convex in a paraxial region, and predetermined conditional expressions are satisfied.

Abstract: An input device includes a display unit that displays an aerial image, and a detection unit that detects a user operation related to the aerial image. The display unit includes a light guide plate disposed between a half mirror and a retroreflective plate and a light source irradiating the light guide plate. The display unit displays the aerial image of a light diffusion surface formed on the light guide plate in response to incident light. When the user operation related to the aerial image is detected, the display unit turns off the light source to notify a user of input confirmation.

Abstract: There is provided an imaging lens with excellent optical characteristics while satisfying demand of low-profileness and low F-number. An imaging lens comprises, in order from an object side to an image side, a first lens with positive refractive power formed in a biconvex shape having an object-side surface and an image-side surface being convex in a paraxial region, a second lens with negative refractive power in a paraxial region, a third lens with the negative refractive power in a paraxial region, a fourth lens with the negative refractive power in a paraxial region, and a fifth lens with the positive refractive power having an image-side surface being convex in a paraxial region, and predetermined conditional expressions are satisfied.

Abstract: A method for manufacturing an optical element includes forming an optical element unit comprised of an optical material such as glass and having an outer shape of a regular triangle or a regular hexagon, arranging a plurality of optical element units two-dimensionally on a substrate so as to have a structure imitating a molecular structure of graphene or a carbon nanotube, and processing the substrate on which the plurality of optical element units are mounted into a desired surface shape.

Abstract: There is provided an imaging lens with excellent optical characteristics while satisfying demand of low-profileness and low F-number. An imaging lens comprises, in order from an object side to an image side, a first lens with positive refractive power formed in a biconvex shape having an object-side surface and an image-side surface being convex in a paraxial region, a second lens with negative refractive power in a paraxial region, a third lens with the negative refractive power in a paraxial region, a fourth lens with the negative refractive power in a paraxial region, and a fifth lens with the positive refractive power having an image-side surface being convex in a paraxial region, and predetermined conditional expressions are satisfied.

Abstract: An image display apparatus includes a display unit having a screen that displays an image, an image generation unit that generates an image to be displayed on the screen, a Fresnel lens disposed at a predetermined distance from the screen, a specular-reflection preventing device that causes a rear surface of the Fresnel lens to move so as to be tilted at an angle at which incident light from a user side where a user sees the image is not specularly reflected to the user side, and an image correction unit that corrects image distortion caused by the specular-reflection preventing device.

Abstract: An input device includes a display unit that displays an aerial image, and a detection unit that detects a user operation related to the aerial image. The display unit includes a light guide plate disposed between a half mirror and a retroreflective plate and a light source irradiating the light guide plate. The display unit displays the aerial image of a light diffusion surface formed on the light guide plate in response to incident light. When the user operation related to the aerial image is detected, the display unit turns off the light source to notify a user of input confirmation.

Abstract: There is provided an imaging lens with high-resolution which realizes the low-profileness, wide field of view and low F-value well balance. An imaging lens comprising in order from an object side to an image side, a first lens having positive refractive power, a second lens having negative refractive power, a third lens being a double-sided aspheric lens, a fourth lens having a meniscus shape with a concave surface facing the object side near an optical axis, a fifth lens being a double-sided aspheric lens, and a sixth lens having the concave surface facing the image side near the optical axis, wherein the image-side surface of said sixth lens is an aspheric surface which changes to the convex surface at a peripheral portion, and a total track length is 6.0 mm or less and below conditional expressions (2) and (3) are satisfied: 20<?d3<32??(2) 20<?d5<32??(3) where ?d3: abbe number at d-ray of the third lens ?d5: abbe number at d-ray of the fifth lens.

Abstract: An imaging lens includes, in order from an object side to an image side, a first lens being a double-sided aspheric lens, a second lens, a third lens having positive refractive power, a fourth lens, a fifth lens, and a sixth lens being a double-sided aspheric lens and having negative refractive power and a concave surface facing the image side near an optical axis, wherein an image-side surface of said sixth lens is an aspheric surface changing to the convex surface at a peripheral area, and a below conditional expression (1) is satisfied: ?0.68<(N1?1)/(r1×f)×1000<0.68??(1) where N1: refractive index at d-ray of the first lens, r1: paraxial curvature radius of the object-side surface of the first lens, and f: focal length of an overall optical system.

Abstract: There is provided an imaging lens with high-resolution which realizes the low-profileness, wide field of view and low F-value well balance. An imaging lens comprising in order from an object side to an image side, a first lens having positive refractive power, a second lens having negative refractive power, a third lens being a double-sided aspheric lens, a fourth lens having a meniscus shape with a concave surface facing the object side near an optical axis, a fifth lens being a double-sided aspheric lens, and a sixth lens having the concave surface facing the image side near the optical axis, wherein the image-side surface of said sixth lens is an aspheric surface which changes to the convex surface at a peripheral portion, and a total track length is 6.0 mm or less and below conditional expressions (2) and (3) are satisfied: 20<?d3<32??(2) 20<?d5<32??(3) where ?d3: abbe number at d-ray of the third lens ?d5: abbe number at d-ray of the fifth lens.