Abstract: A communication system (1) includes a plurality of communication apparatuses (10) and a control apparatus (20), the control apparatus (20) including a control unit (21), the control unit (21) including a management unit (21a) that manages, for each of the plurality of communication apparatuses (10), the number of connections that are capable of being established, and the number of established connections.

Abstract: An air traffic control system (31) according to the present disclosure includes a communication unit (4) configured to receive, from a communication terminal (40), an image including a flying object (2) captured by the communication terminal (40) and position information about the communication terminal (40), an estimation unit (8) configured to estimate a position of the flying object (2) using background information and the position information included in the image, and an identification unit (5) configured to identify the flying object (2) using the estimated position of the flying object (2). The communication unit (4) transmits information about the identified flying object (2) to the communication terminal (40).

Abstract: A communication apparatus (10) includes: at least one communication means (11) that is configured to be capable of transmitting and receiving directional communication media; a specification means (12) that specifies at least one connection destination candidate by scanning with use of the at least one communication means; and a connection establishment means (13) that establishes connection with the at least one connection destination candidate specified by the specification means.

Abstract: A flying object according to example embodiments includes an airframe ID control unit configured to hold an airframe ID of the flying object changed according to a predetermined change pattern, and a communication unit configured to transmit the airframe ID. An air traffic control system according to the example embodiments includes a communication unit configured to acquire a first airframe ID and position information transmitted from a flying object, and an identification unit configured to identify the flying object using the first airframe ID. When the communication unit acquires a second airframe ID different from the first airframe ID after acquiring the first airframe ID, the identification unit determines whether or not the second airframe ID indicates the flying object based on a change between the position information at the time of acquiring the first airframe ID and the position information at the time of acquiring the second airframe ID.

Abstract: Please delete the Abstract of the Disclosure, and replace it with the following: A light-receiving device that includes a substrate which transmits light in the wavelength band of a spatial light signal to be received, an optical antenna which is disposed on a first surface of the substrate, which receives the spatial light signal, which optically guides signal light derived from the spatial light signal along the in-plane direction of the substrate toward an emission end, and which outputs the signal light from the emission end toward the substrate, and a light-receiving element which is disposed such that a light-receiving surface faces a second surface of the substrate opposite from the first surface, and which receives, at the light-receiving surface, the signal light output from the optical antenna.

Abstract: A communication system (1) includes a plurality of communication apparatuses (10) and a control apparatus (20), the control apparatus (20) including a control unit (21) including: a related information acquisition unit (22) that acquires related information related to the communication apparatuses; a connection request acquisition unit (23) that acquires a connection request from a new terminal; a determination unit (24) that determines a communication apparatus which is to be connected to the new terminal; and an instruction unit (25) that instructs the determined communication apparatus to carry out scanning with respect to the new terminal.

Abstract: A communication apparatus (20) according to an example aspect of the present invention includes: at least one communication means (21) that is configured to be capable of transmitting and receiving directional communication media; and a determination means (22) that determines at least one communication destination with which to communicate by the at least one communication means, in the case of determination of communication with a plurality of communication destinations, the determination means selecting the plurality of communication destinations so that an angle between the plurality of communication destinations as viewed from the communication apparatus is not less than a predetermined angle.

Abstract: To provide a free space optical communication apparatus with an increased efficiency of optical axis alignment. A free space optical communication apparatus (1) includes: light transmitting sections (10); and an optical axis alignment section (20) configured to align an optical axis of each of the light transmitting sections (10) with a corresponding one of light receiving sections (130) included in a communication target. The optical axis alignment section (20) causes at least one of the light transmitting sections (10) to emit scan light (3) while varying an emitting direction, and aligns an optical axis of a light transmitting section (10) which is other than the at least one light transmitting section (10), based on an emitting direction of the scan light (3) emitted from the at least one light transmitting section (10) and received by a corresponding one of the light receiving sections (130).

Abstract: A transmitter including a light source, a spatial optical modulator including a modulation part in which a phase image according to a spatial optical signal to be transmitted is set and irradiated with light emitted from the light source, an optical diffuser that diffuses modulated light modulated by the modulation part of the spatial optical modulator, and a ball lens that enlarges and projects the modulated light diffused by the optical diffuser.

Abstract: Provided is a transmission device that includes a light source that includes emitters, a spatial light modulator that includes a modulation part in which modulation regions are set, a concentrator that converts modulated light modulated in the modulation regions into parallel light, a projector that is disposed at a subsequent stage of the concentrator and includes at least one reflector including a curved mirror having a reflection surface of a curved shape having a curvature according to a projection angle of projection light transmitted as a spatial light signal and a rotator rotatably supporting the curved mirror, and a controller that controls the rotator to adjust a reflection direction of the curved mirror for each of the reflectors, sets a phase image used for spatial light communication in the modulation regions, and controls the plurality of emitters such that each of the modulation regions is irradiated with light.

Abstract: A projection device a includes a light source that emits parallel light, a spatial light modulator that has a modulation part that modulates a phase of the parallel light emitted from the light source, a liquid crystal projection lens that includes a liquid crystal region on which modulated light modulated by the spatial light modulator is incident and that projects the modulated light in a lens region dynamically formed in the liquid crystal region as projection light, and a control unit that causes the lens region to be formed at a desired position in the liquid crystal region of the liquid crystal lens, sets a phase image corresponding to the projection light projected toward a projection target, to the modulation part of the spatial light modulator, and controls the light source to emit the parallel light toward the modulation part to which the phase image is set.

Abstract: Provided is a light receiving device includes a ball lens and a light receiver disposed in a condensing region of the ball lens. The light receiver includes a light receiving element array in which light receiving units each of which includes a light receiving element and an amplifier circuit associated with the light receiving element are disposed in an array, and a selection circuit that selects a light receiving unit included in the light receiving element array.

Abstract: Provided is a light receiving device including a ball lens, a concave lens that is arranged in a light collecting region of the ball lens, a reflection element that is arranged in association with the concave lens and has a reflection surface that diffracts and reflects an optical signal collected by the concave lens, and a light receiving element that is arranged in association with the reflection element and receives the optical signal diffracted and reflected by the reflection surface of the reflection element.

Abstract: A provision determination system (100) includes at least one processor (1301), the at least one processor (1301) executing: an obtaining process (S201) of obtaining information indicating a load of communication of a first free-space optical communication apparatus connected to a free-space optical communication network; and a determining process (S202) of making a determination on necessity for provision of a second free-space optical communication apparatus connected to the free-space optical communication network, the determination being made in accordance with the information indicating the load of the communication.

Abstract: A transmitter that includes a light source that includes a plurality of emitters, a spatial light modulator that includes a modulation part in which a plurality of modulation regions associated with each of a plurality of the emitters is set, curved mirrors that have a curved reflecting surface having a curvature relevant to a projection angle of projection light transmitted as a spatial light signal and disposed in association with each of a plurality of the modulation regions in such a way that, on the reflecting surface, modulated light modulated in each of a plurality of the modulation regions set in the modulation part of the spatial light modulator is reflected, and a light shielding band that is disposed between the spatial light modulator and the curved mirrors and removes an unnecessary light component included in the modulated light modulated in each of a plurality of the modulation regions.

Abstract: A receiver includes a ball lens, a light receiving element array including a plurality of light receiving elements arranged around the ball lens, and a light guide including a plurality of reflection units that guide optical signals concentrated by the ball lens toward the light receiving elements. Each of the reflection units includes a first reflector associated with one of the plurality of light receiving elements and having reflecting surfaces formed on inner side surfaces tapered from the ball lens toward the light receiving element, and a second reflector disposed inside the first reflector and formed by combining double-sided mirrors having reflecting surfaces parallel to the reflecting surfaces of the first reflector.

Abstract: A receiver includes a light receiver including a light-receiving ring including a plurality of light-receiving elements arranged in an annular shape and a light-receiving plate including at least one light-receiving element, a ball lens placed on a ring formed by the light-receiving ring, and a reflector arranged in a gap formed between the light-receiving ring and the light-receiving plate. The plurality of light-receiving elements constituting the light-receiving ring are arranged with a light-receiving surface facing an inner side of the ring formed by the light-receiving ring. The light-receiving element included in the light-receiving plate is disposed inside the ring formed by the light-receiving ring with a light-receiving surface facing the ball lens placed on the light-receiving ring.

Abstract: A display control apparatus (2000) detects, by using audio data including a sound around a display device (10), a first situation where target information being displayed by the display device (10) can be viewed by a person other than a specific person (30), or detects, by using image data including surroundings of the display device (10), a second situation where the target information being displayed by the display device (10) can be captured by a camera. The display control apparatus (2000) changes an output state of the target information in the display device (10) in response to detection of the first situation or the second situation. A change of the output state is processing of stopping output of the target information or processing of reducing visibility of the target information as compared with visibility before a change.

Abstract: A network apparatus (2000) includes a port (20). A target apparatus (10) is connected to the port (20). The network apparatus (2000) computes a communication feature value related to communication between the target apparatus (10) and the port (20). The network apparatus (2000) determines whether a communication feature value computed for the target apparatus (10) and a communication feature value predetermined for a specific apparatus match each other. The network apparatus (2000) performs predetermined control processing when it is determined that the communication feature value for the target apparatus and the communication feature value for the specific apparatus do not match each other.

Abstract: A conversation surveillance apparatus (2000) detects a plurality of persons (a human group (40)) who have a conversation within a predetermined distance in a surveillance area (10) from video data (32). The conversation surveillance apparatus (2000) determines the duration of the conversation held by the human group (40) and puts the determined duration of the conversation into a storage device in association with identification information of the human group (40). The conversation surveillance apparatus (2000) determines whether the total duration of the conversations held by the human group (40) within a predetermined period of time is equal to or larger than a threshold using the information stored in the storage device.