Abstract: A lens system provides to a user, a high-definition image in which generation of concentric circles is reduced. The lens system has one or more Fresnel lenses. A lens surface of each of the Fresnel lenses has a plurality of grooves that is concentrically formed. Both a pitch which is the distance between two adjacent grooves and the depth of each of the plurality of grooves vary with the distance from an optical axis that passes through the center of the lens system.

Abstract: A lens system for an imaging device is provided, the lens system comprising: a first lens group, having a fixed position along an optical axis Z of the lens system, the first lens group comprising a pair of lenses, each of the pair of lenses having at least one lens surface that is a free-form surface,; and a second lens group, arranged along the optical axis Z of the lens system, comprising a plurality of rotationally symmetrical lenses; wherein a first lens of the pair of lenses of the first lens group is configured to be moveable along a Y-axis of the lens system perpendicular to the optical axis Z of the lens system, and a second lens of the pair of lenses of the first lens group is configured to be moveable in an opposite direction to the first lens of the pair of lenses along the Y-axis.

Abstract: There is provided a display system used for a head mounted display including a head mounted device having a lens for guiding image light to an eye of a user and configured to be mounted on a head of the user and a portable terminal having an imaging unit for photographing a front of a display surface and capable of being housed in the head mounted device. The display system includes a display control section configured to display a moving image on the display surface, an image information obtaining section configured to obtain image information photographed by the imaging unit, and a position information obtaining section configured to obtain position information of an optical axis of the lens on the display surface on the basis of position information of at least two reference positions whose relative positions with respect to the optical axis are determined in advance, the at least two reference positions being included in the image information.

Abstract: Proposed is a lens system capable of providing, to a user, a high-definition image in which generation of concentric circles is reduced. The lens system has one or more Fresnel lenses. A lens surface of each of the Fresnel lenses has a plurality of grooves that is concentrically formed. Both a pitch which is the distance between two adjacent grooves and the depth of each of the plurality of grooves vary with the distance from an optical axis that passes through the center of the lens system.

Abstract: There is provided a Fresnel lens capable of restraining flare from occurring. Each of a plurality of prisms (11) of a Fresnel lens (10) has an effective surface (Es) and a noneffective surface (Ns). In each of the prisms (11), the noneffective surface (Ns) has a first noneffective surface (Ns1) and a second noneffective surface (Ns2) that is closer to a crest (11c) of the prism (11) than the first noneffective surface (Ns1). The first noneffective surface is inclined to an optical axis (Z1).

Abstract: A first lens unit and a third lens unit are constituted by a lens which is rotationally symmetrical with respect to an optical axis and are disposed on the same optical axis, a first freeform-curved surface lens and a second freeform-curved surface lens have the same shape and are disposed to be rotated at 180 degrees with respect to the optical axis, the first freeform-curved surface lens and the second freeform-curved surface lens are movable in a Y-axis direction when the optical axes of the first lens unit and the third lens unit are set to be a Z-axis, an axis perpendicular to the Z-axis on an image surface is set to be a Y-axis, and an axis perpendicular to the Y-axis and the Z-axis on the image surface is set to be an X-axis, a refractive power of the second lens unit is variable due to the first freeform-curved surface lens and the second freeform-curved surface lens moving in opposite directions, and the first freeform-curved surface lens and the second freeform-curved surface lens are moved in the Y

Abstract: There is provided a display system used for a head mounted display including a head mounted device having a lens for guiding image light to an eye of a user and configured to be mounted on a head of the user and a portable terminal having an imaging unit for photographing a front of a display surface and capable of being housed in the head mounted device. The display system includes a display control section configured to display a moving image on the display surface, an image information obtaining section configured to obtain image information photographed by the imaging unit, and a position information obtaining section configured to obtain position information of an optical axis of the lens on the display surface on the basis of position information of at least two reference positions whose relative positions with respect to the optical axis are determined in advance, the at least two reference positions being included in the image information.

Abstract: Proposed is a lens system capable of providing, to a user, a high-definition image in which generation of concentric circles is reduced. The lens system has one or more Fresnel lenses. A lens surface of each of the Fresnel lenses has a plurality of grooves that is concentrically formed. Both a pitch which is the distance between two adjacent grooves and the depth of each of the plurality of grooves vary with the distance from an optical axis that passes through the center of the lens system.

Abstract: In a display apparatus body (10A), a first polarization plate (31), a first wave plate (32), a reflection layer (33), a second wave plate (35), and a second polarization plate (36) are arranged between a display element (De) and a lens (S) and are lined up in this order from the display element (De) toward the lens (S). Further, the reflection layer (33) includes reflection regions (E1) that correspond to positions of non-light emission regions (R2) of the display element (De) and that reflect light and includes light transmission regions (E2) that correspond to positions of a plurality of light emission regions (R1) and that transmit light. This can obtain a display apparatus that can improve the use efficiency of light emitted from a display element.

Abstract: A lens unit includes a first lens and a second lens. The first lens is a Fresnel lens that has a first lens surface having a Fresnel structure on the second lens side, and has a positive refractive power. The second lens is a Fresnel lens that has a second lens surface having a Fresnel structure on the first lens side, and has a positive refractive power.

Abstract: Provided is a display device in which generation of a ghost can be restrained. A polarizing plate is disposed adjacently to a display section. A ¼ wavelength plate is disposed adjacently to the polarizing plate. A polarizing plate is disposed adjacently to a lens. A ¼ wavelength plate is disposed adjacently to the polarizing plate. A beam splitter is disposed between the ¼ wavelength plate and the ¼ wavelength plate. The beam splitter is disposed at such a position that the air-equivalent optical path length of light that is reflected by the polarizing plate and is thereafter reflected by the beam splitter from emission of the light from the display section to transmission of the light through the lens and the air-equivalent optical path length of light that is reflected by the beam splitter and is thereafter reflected by the polarizing plate from emission of the light from the display section to transmission of the light through the lens are equal.

Abstract: Methods and apparatus provide for: disposing a display unit in front of eyes of a user; disposing an optical system between the display unit and the eyes of the user; and disposing an imaging unit between the display unit and the optical system, the imaging unit imaging the display unit in which an image of the eyes of the user is reflected; and irradiating light onto the eyes of the user, where the imaging includes imaging the eyes of the user reflected in the display unit by reflecting the light irradiated by the light-irradiation unit by the eyes of the user.

Abstract: Provided is a display device in which generation of a ghost can be restrained. A polarizing plate is disposed adjacently to a display section. A ¼ wavelength plate is disposed adjacently to the polarizing plate. A polarizing plate is disposed adjacently to a lens. A ¼ wavelength plate is disposed adjacently to the polarizing plate. A beam splitter is disposed between the ¼ wavelength plate and the ¼ wavelength plate. The beam splitter is disposed at such a position that the air-equivalent optical path length of light that is reflected by the polarizing plate and is thereafter reflected by the beam splitter from emission of the light from the display section to transmission of the light through the lens and the air-equivalent optical path length of light that is reflected by the beam splitter and is thereafter reflected by the polarizing plate from emission of the light from the display section to transmission of the light through the lens are equal.

Abstract: A distance-measuring device includes first and second stereoscopic cameras each to be used to measure the distance to an object included in an imaging range. The first stereoscopic camera includes two imaging elements arranged side by side in a first direction, and the second stereoscopic camera includes two imaging elements arranged side by side in a second direction. The second direction is defined as a direction which intersects a plane containing the first direction and an imaging direction of the first stereoscopic camera.

Abstract: Methods and apparatus provide for: disposing a display unit in front of eyes of a user; disposing an optical system between the display unit and the eyes of the user; and disposing an imaging unit between the display unit and the optical system, the imaging unit imaging the display unit in which an image of the eyes of the user is reflected; and irradiating light onto the eyes of the user, where the imaging includes imaging the eyes of the user reflected in the display unit by reflecting the light irradiated by the light-irradiation unit by the eyes of the user.

Abstract: There are provided a Fresnel lens and a method of manufacturing the Fresnel lens which can suppress a flare which is generated in an image visually recognized through the Fresnel lens so as to extend toward a center of a lens. A lens surface and a non-lens surface are formed in each of lens portions. The non-lens surface includes a rise surface and a coupling surface. The rise surface is a surface along an optical axis of a Fresnel lens. The coupling surface is a surface which is formed on a top portion of each of the lens portions and couples the lens surface of the lens portion and the rise surface of the lens portion to each other, and which has a width extending in a radial direction of the Fresnel lens. A light absorbing portion is provided in a position along the optical axis of the Fresnel lens which passes through the coupling surface.

Abstract: Provided is a head-mounted display in which it is easy to photograph eyes of a user that wears the head-mounted display. The HMD that is worn by the user includes a display unit disposed in front of the eyes of the user, an optical system disposed between the display unit and eyes of the user, and an imaging unit disposed between the display unit and the optical system, the imaging unit imaging the display unit in which an image of the eyes of the user is reflected.

Abstract: There are provided a Fresnel lens and a method of manufacturing the Fresnel lens which can suppress a flare which is generated in an image visually recognized through the Fresnel lens so as to extend toward a center of a lens. A lens surface and a non-lens surface are formed in each of lens portions. The non-lens surface includes a rise surface and a coupling surface. The rise surface is a surface along an optical axis of a Fresnel lens. The coupling surface is a surface which is formed on a top portion of each of the lens portions and couples the lens surface of the lens portion and the rise surface of the lens portion to each other, and which has a width extending in a radial direction of the Fresnel lens. A light absorbing portion is provided in a position along the optical axis of the Fresnel lens which passes through the coupling surface.

Abstract: A distance-measuring device includes first and second stereoscopic cameras each to be used to measure the distance to an object included in an imaging range. The first stereoscopic camera includes two imaging elements arranged side by side in a first direction, and the second stereoscopic camera includes two imaging elements arranged side by side in a second direction. The second direction is defined as a direction which intersects a plane containing the first direction and an imaging direction of the first stereoscopic camera.

Abstract: Provided is a head-mounted display in which it is easy to photograph eyes of a user that wears the head-mounted display. The HMD that is worn by the user includes a display unit disposed in front of the eyes of the user, an optical system disposed between the display unit and eyes of the user, and an imaging unit disposed between the display unit and the optical system, the imaging unit imaging the display unit in which an image of the eyes of the user is reflected.