An image display device includes an inclined transparent plate, a supporting member configured to support a display device with a display to be capable of projecting the image toward the transparent plate, thereby overlapping the image with a frontal view of the object, side walls each extending along one of side faces of the transparent plate. An outline of the frontal view of the object overlaps at least a part of an outline of the image, a perspective view of the object seen through the transparent plate overlaps the image reflected by the transparent plate, and the walls sandwich the transparent plate so that two spaces at upper side and a rear side of the transparent plate are defined, the object being positioned in the rear side space, the upper side space having a brightness different from that of the rear side space.

The purpose is to provide a higher-quality three-dimensional image with a downsized optical system that does not need interpupillary adjustment. An ocular optical system according to the present disclosure includes, on an optical path viewed from an observer side, at least: a first polarization member; a mirror; a second polarization member; and an image display device in this order. A polarized state in the first polarization member and a polarized state in the second polarization member are orthogonal to each other.

Head-mounted display systems and methods of operation that allow users to couple and decouple a portable electronic device such as a handheld portable electronic device with a separate head-mounted device (e.g., temporarily integrates the separate devices into a single unit) are disclosed. The portable electronic may be physically coupled to the head-mounted device such that the portable electronic device can be worn on the user's head. The portable electronic device may be operatively coupled to the head-mounted device such that the portable electronic device and head mounted device can communicate and operate with one another. Each device may be allowed to extend its features and/or services to the other device for the purpose of enhancing, increasing and/or eliminating redundant functions between the head-mounted device and the portable electronic device.

Head-mounted display systems and methods of operation that allow users to couple and decouple a portable electronic device such as a handheld portable electronic device with a separate head-mounted device (e.g., temporarily integrates the separate devices into a single unit) are disclosed. The portable electronic may be physically coupled to the head-mounted device such that the portable electronic device can be worn on the user's head. The portable electronic device may be operatively coupled to the head-mounted device such that the portable electronic device and head mounted device can communicate and operate with one another. Each device may be allowed to extend its features and/or services to the other device for the purpose of enhancing, increasing and/or eliminating redundant functions between the head-mounted device and the portable electronic device.

An apparatus and method for real-time audio processing employs a gaze detection sensor to detect a direction of a user's gaze and output a gaze signal corresponding to the detected direction of the user's gaze. A digital signal processing unit responds to a plurality of signals corresponding to a plurality of sounds received at the apparatus, and the determined direction of gaze to identify a signal of interest from the plurality of signals using the gaze signal. The signal of interest is processed for output to the user. In embodiments, a microphone array provides the plurality of signals. An imaging sensor may work with either the microphone array or the gaze detection sensor to identify the signal of interest.

A surgical retractor includes a plurality of cameras integrated therein. One such retractor includes a tubular retractor and an insert supporting said plurality of cameras can be disposed within a tubular retractor.

An apparatus and method for real-time audio processing employs a gaze detection sensor to detect a direction of a user's gaze and output a gaze signal corresponding to the detected direction of the user's gaze. A digital signal processing unit responds to a plurality of signals corresponding to a plurality of sounds received at the apparatus, and the determined direction of gaze to identify a signal of interest from the plurality of signals using the gaze signal. The signal of interest is processed for output to the user. In embodiments, a microphone array provides the plurality of signals. An imaging sensor may work with either the microphone array or the gaze detection sensor to identify the signal of interest.

An image display device according to an embodiment of the present technology include an emission portion, an irradiation target, and an optical portion. The emission portion emits image light along a predetermined axis. The irradiation target is disposed at at least a part around the predetermined axis. The optical portion controls an incident angle of the image light on the irradiation target, the image light having been emitted from the emission portion, the optical portion being disposed in a manner that the optical portion faces the emission portion on the basis of the predetermined axis.

Provided are a liquid crystal diffraction element that can make the brightness of light emitted from a light guide plate uniform and a light guide element. The liquid crystal diffraction element includes: an optically-anisotropic layer that is formed of a composition including a liquid crystal compound, in which the optically-anisotropic layer has a liquid crystal alignment pattern in which a direction of an optical axis derived from the liquid crystal compound continuously rotates in at least one in-plane direction, and a diffraction efficiency of the optically-anisotropic layer increases from one side to another side in the one in-plane direction.

The purpose is to provide a higher-quality three-dimensional image with a downsized optical system that does not need interpupillary adjustment. An ocular optical system according to the present disclosure includes, on an optical path viewed from an observer side, at least: a first polarization member; a mirror; a second polarization member; and an image display device in this order. A polarized state in the first polarization member and a polarized state in the second polarization member are orthogonal to each other.