Abstract: An obstacle monitoring system includes: a sensing means; a first obstacle detection means; and a control means for selectively executing a plurality of control modes including a first control mode in which a moving speed of a moving body is a first moving speed and a sensing field of view of the sensing means is a first field of view, and a second control mode in which a moving speed of the moving body is a second moving speed and a sensing field of view of the sensing means is a second field of view. When the first obstacle detection means detects the obstacle while the control means is executing the first control mode, the control means executes the second control mode in such a way as to capture the obstacle within the second field of view.

Abstract: A virtual-image display device includes: a first display unit including a first image element, a first projection optical system, and a first mirror; a second display unit including a second image element, a second projection optical system, and a second mirror; a coupling member configured to couple the first display unit and the second display unit; a penetration-type fitting structure formed at an attaching section and at a support portion, the attaching section being formed at the first display unit, the support portion being provided at the coupling member; and a photocurable-type adhesive material held between the attaching section and the support portion, in which an additional light transmitting structure is formed at one of the attaching section and the support portion, and the light transmitting structure is configured to cause light to reach a boundary region between the attaching section and the support portion.

Abstract: A method for producing a ceramic sintered body includes: preparing a molded body containing a nitride fluorescent material having the composition containing Si; N; at least one alkaline earth metal element M1; and a metal element M2 being at least one selected from the group consisting of Eu, Ce, Tb, and Mn, to obtain a composition as described in the disclosure; obtaining a first sintered body by performing primary calcination of the molded body; obtaining a second sintered body by performing secondary calcination of the first sintered body in contact with a solid composed of a molybdenum metal or an alloy containing molybdenum as a main component; and obtaining a third sintered body by performing third calcination of the second sintered body while being placed in a container containing a metal having a melting point higher than that of the molybdenum metal.

Abstract: A virtual image display device includes an image element, a projection optical system configured to project an image formed on the image element, a case configured to house the image element and the projection optical system in a positioned state, and an optical appearance component on which image light emitted from the projection optical system is incident. The optical appearance component includes a first bonding surface and a second bonding surface which extend in mutually intersecting directions and are each bonded to the case, and the second bonding surface includes two portions provided at separated positions with the case interposed therebetween.

Abstract: A head-mounted display apparatus includes an image forming element, a holder including a supporting member supporting the image forming element and a fixing member coupled to the supporting member, an optical member on which image light from the image forming element is incident, and a case configured to house the optical member and hold the image forming element therein via the holder, wherein the holder includes a transparent portion, the fixing member is fixed to an outside of the case by an adhesive material, and the adhesive material is interposed between the transparent portion and the case.

Abstract: A display device includes an image element, a prism mirror that receives image light emitted from the image element through a light incident surface, reflects the image light with an inner reflection surface, and emits the image light from a light emission surface, and a see-through mirror that reflects the image light emitted from the prism mirror toward a pupil position, wherein the prism mirror emits the image light incident from a front to be bent in a direction inclined with respect to the front, and a light emission side of an image source that includes the image element and the prism mirror is covered with a light transmission window that blocks dust.

Abstract: A virtual image display apparatus according to the present disclosure includes a first display module, a second display module, and a coupling portion having an adjustable structure. The adjustable structure adjusts the first display module with respect to the second display module at least a relative rotational position and relative positions in longitudinal and depth directions.

Abstract: An HMD includes a first display element, a holder configured to hold the first display element, a first projection optical system configured to project an image formed on the first display element, a barrel which is a case configured to house the first projection optical system in a positioned state, and a dust-proof structure configured to achieve fixing of the holder and the barrel while ensuring dust-proofing of the holder and the barrel, wherein the holder includes a support frame inserted into the barrel through an insertion opening formed at the barrel while supporting the first display element, and a base plate coupled to a root of the support frame, the barrel includes a pedestal facing the base plate, and the dust-proof structure includes an adhesive material extending along a periphery of the base plate and protruding to the pedestal.

Abstract: An HMD includes a first display element, a holder configured to hold the first display element, a first projection optical system configured to project an image formed on the first display element, and a barrel which is a case configured to house the first projection optical system in a positioned state, the holder includes a support frame that supports the first display element and a base plate coupled to an upper portion of the support frame and extending in a direction intersecting the support frame, and an end portion of the support frame is inserted into the barrel through an insertion opening formed at the barrel, and the base plate is fixed to the barrel while covering the insertion opening.

Abstract: An HMD includes a first display element, a holder configured to hold the first display element, a first projection optical system configured to project an image formed on the first display element, a case including an insertion opening into which the first display element supported by the holder is inserted and configured to house the first projection optical system in a positioned state, and a first metallic frame configured to support the case, wherein the first metallic frame includes a receiving opening larger than an outline of the holder when viewed from an insertion direction of the first display element.

Abstract: A virtual image display device includes a first acquisition unit configured to acquire a first image from an information terminal, a second acquisition unit configured to acquire a second image different from the first image, a correction unit configured to distort the first image, a generation unit configured to generate a third image or a fourth image including the distorted first image and the second image, and a display element configured to display the third image or the fourth image.

Abstract: A method of manufacturing an optical element including, a first step of, after affixing a hologram forming material to a glass substrate having a marking portion, performing interference exposure on the hologram forming material, thereby forming a hologram layer at the glass substrate, and a second step of affixing the hologram layer peeled off from the glass substrate to a plastic substrate having a first alignment mark, wherein in the second step, the first alignment mark on the plastic substrate, and a second alignment mark formed at a position corresponding to the marking portion in the hologram layer during the interference exposure are used to implement positioning of the plastic substrate and the hologram layer.

Abstract: An optical member includes a plurality of optically effective surfaces, and a plurality of measurement reference members that are associated with the plurality of optically effective surfaces and each of which serves as a reference for positioning of the plurality of optically effective surfaces. In this case, a relative positional relationship of the optically effective surfaces can be determined, and the optical performance of the optical member can be accurately evaluated.

Abstract: An optical unit and a virtual image display device, that is, an HMD include a plurality of optical members, and the plurality of optical members have, at non-coupling portion, measurement reference members that serve as references for arrangement, respectively, and the plurality of measurement reference members of the plurality of optical members are arranged in a unified direction.

Abstract: A transmissive image display device includes an image generation part configured to emit a light, and a light-guiding optical system configured to guide the light. The light-guiding optical system includes a first deflection part configured to deflect the light, and a second deflection part configured to further deflect the light deflected by the first deflection part to guide the light to a position of the exit pupil while transmitting a portion of external light, a first external light transmittance adjustment part is provided outside an optical path of the light between the first deflection part and the second deflection part, and an average external light transmittance of the first external light transmittance adjustment part is higher than one of an average external light transmittance of the first deflection part and an average external light transmittance of the second deflection part lower than the other.

Abstract: An optical element includes a substrate and a first hologram element provided on one side of the substrate, and a second hologram element provided on another side of the substrate. The first hologram element is provided to overlap with the second hologram element in a front view. The first hologram element includes a first hologram layer that diffracts part of incident light in a first wavelength band and that transmits another part of the incident light in the first wavelength band. The second hologram element includes a second hologram layer that diffracts, toward the first hologram layer through diffraction, part of light in the first wavelength band transmitted through the first hologram layer and that transmits other part of the light in the first wavelength band transmitted through the first hologram layer.

Abstract: In a display device, an image having an aspect not equal to 1 is formed by an image forming unit configured to form an image, and the image is guided as an image light to a display position by an optical system. The optical system, which is provided with a diffraction optical element, deflects the image light. In the diffraction optical element, a pitch direction of a pattern for deflecting the image light coincides with a direction in which the aspect of the image is narrow. In the display device, the direction in which the image light is deflected by the diffraction optical element coincides with the direction in which the aspect of the image formed is narrow, thus making it possible to suppress unevenness of brightness and hue within a plane of an image displayed.

Abstract: An image in a predetermined hue is displayed at a display surface, and is emitted as image light. The image light is guided to a display position by an optical system, and is deflected by a diffraction optical element. The emitted image light includes light emitted from a first position of the display surface and light emitted from a second position of the display surface. A deflection angle at which the light emitted from the first position is diffracted by the diffraction optical element is larger than a deflection angle at which the light emitted from the second position is diffracted by the diffraction optical element. Of the image light in a wavelength range expressing the hue, a wavelength peak of the light emitted from the first position is present on a long wavelength side with respect to a wavelength peak of the light emitted from the second position.

Abstract: A virtual image display apparatus includes an image light emitting unit configured to emit image light, and a see-through mirror which is an optical member having a reflective film that reflects the image light, wherein the see-through mirror includes a first region on which a light ray of the image light corresponding to a center angle of view is incident and a second region on which a light ray of the image light which different from the light ray corresponding to the center angle of view is incident, a film thickness in the first region of the reflective film is thicker than a film thickness in the second region, and the first region of the reflective film has reflectivity characteristics corresponding to a wavelength band which is wider toward the long wavelength side than a wavelength band of the image light emitted from the image light emitting unit.

Abstract: Provided is a display method for displaying an image based on a color original image. The display method includes guiding an image light corresponding to the color original image to a display position by an optical system, and deflecting a traveling direction of the image light to an observer and performing display by a diffraction optical element. At the time of displaying the color original image, the image light entering the first diffraction optical element includes a light entering at a first angle and a light entering at a second angle that is larger than the first angle, a chromaticity range of the image of the color original image at a position corresponding to the light entering at the first angle is limited to be close to a chromaticity range of the light entering at the second angle.