Abstract: An indicator detection method includes operating in a first mode and operating in a second mode. The first mode includes detecting a position of a first indicator on a operation surface by detecting first light emitted by the first indicator, emitting second light by a light emitting device, and detecting a position of a second indicator on the operation surface by detecting reflected light of the second light reflected by the second indicator. The second mode includes reducing a light amount of the second light when it is determined that the first indicator is in contact with the operation surface, and detecting the position of the first indicator on the operation surface by detecting the first light in a state where the light amount of the second light is reduced.

Abstract: An indicator detection method includes operating in a first mode and operating in a second mode. The first mode includes detecting a position of a first indicator on a operation surface by detecting first light emitted by the first indicator, emitting second light by a light emitting device, and detecting a position of a second indicator on the operation surface by detecting reflected light of the second light reflected by the second indicator. The second mode includes reducing a light amount of the second light when it is determined that the first indicator is in contact with the operation surface, and detecting the position of the first indicator on the operation surface by detecting the first light in a state where the light amount of the second light is reduced.

Abstract: A pointing element configured to instruct an operation by being pressed against an operation surface includes a pressurizing part, a pressure sensor configured to detect a variation in the pressurizing part, an opposed part opposed to the pressure sensor, a pressing part configured to change a pressing force of pressing the opposed part against the pressure sensor in accordance with the variation in the pressurizing part caused by the pointing element pressed against the operation surface, a signal generation section configured to receive a first signal having a level based on the pressing force from the pressure sensor, and generate a second signal by changing the level of the first signal, and an output section configured to output information based on the second signal to outside of the pointing element.

Abstract: A pointing element configured to instruct an operation by being pressed against an operation surface includes a pressurizing part, a pressure sensor configured to detect a variation in the pressurizing part, an opposed part opposed to the pressure sensor, a pressing part configured to change a pressing force of pressing the opposed part against the pressure sensor in accordance with the variation in the pressurizing part caused by the pointing element pressed against the operation surface, a signal generation section configured to receive a first signal having a level based on the pressing force from the pressure sensor, and generate a second signal by changing the level of the first signal, and an output section configured to output information based on the second signal to outside of the pointing element.

Abstract: The pointing body includes a receiving section configured to receive a sync signal periodically transmitted from a projector, a processing section configured to perform a process in sync with the sync signal received by the receiving section, and a control section configured to control supply of power to the receiving section, wherein the control section predicts timing when the sync signal is transmitted based on the sync signal received by the receiving section, and switches between a first period in which the power is supplied to the receiving section and a second period in which supply of the power to the receiving section is restricted based on the timing predicted.

Abstract: An image projection system includes a projector and a light pen. The projector includes: an image pickup unit which performs image pickup in a periodically repeated image pickup period and does not perform image pickup in a non-image pickup period; a detection unit which detects a pointed position of the light pen; and an infrared signal receiving unit which receives pointing element information transmitted from the light pen. The light pen includes: a light emitting unit; a control unit; and a storage unit which stores the pointing element information. The light pen performs first light emission in the image pickup period and second light emission corresponding to the pointing element information in the non-image pickup period. The projector detects the pointed position, based on an image of the first light emission picked up by the image pickup unit and receives the pointing element information transmitted via the second light emission.

Abstract: An image projection system includes a projector and a pointing element. The projector includes: an image projection unit which projects an image; an image pickup unit; a detection unit which detects a pointed position of the pointing element, based on an image picked up by the image pickup unit; a synchronization signal transmission unit which transmits a synchronization signal to the pointing element; a screen size acquisition unit which acquires a screen size of the image projected from the image projection unit; and a synchronization signal adjustment unit which sets a light emission intensity of the synchronization signal to a first intensity if the acquired screen size is a first size and which sets the light emission intensity of the synchronization signal to a second intensity that is lower than the first intensity if the acquired screen size is a second size that is smaller than the first size.

Abstract: An image projection system includes a projector and a light pen. The projector includes: an image pickup unit which performs image pickup in a periodically repeated image pickup period and does not perform image pickup in a non-image pickup period; a detection unit which detects a pointed position of the light pen; and an infrared signal receiving unit which receives pointing element information transmitted from the light pen. The light pen includes: a light emitting unit; a control unit; and a storage unit which stores the pointing element information. The light pen performs first light emission in the image pickup period and second light emission corresponding to the pointing element information in the non-image pickup period. The projector detects the pointed position, based on an image of the first light emission picked up by the image pickup unit and receives the pointing element information transmitted via the second light emission.

Abstract: An image projection system includes a projector and a pointing element. The projector includes: an image projection unit which projects an image; an image pickup unit; a detection unit which detects a pointed position of the pointing element, based on an image picked up by the image pickup unit; a synchronization signal transmission unit which transmits a synchronization signal to the pointing element; a screen size acquisition unit which acquires a screen size of the image projected from the image projection unit; and a synchronization signal adjustment unit which sets a light emission intensity of the synchronization signal to a first intensity if the acquired screen size is a first size and which sets the light emission intensity of the synchronization signal to a second intensity that is lower than the first intensity if the acquired screen size is a second size that is smaller than the first size.

Abstract: An interactive system includes a transmitter (light-emitting pen) configured to transmit an optical signal and a projector. The projector includes a signal-intensity setting unit in which intensity information of a synchronization signal is set, a signal-intensity control unit (light-emission control unit) configured to control the intensity of the synchronization signal on the basis of the setting of the signal-intensity setting unit, a synchronization-signal transmitting unit (infrared-light emitting unit) configured to transmit the synchronization signal, and an image pickup unit configured to pick up an image of the optical signal transmitted from the transmitter. The transmitter includes a receiving unit (pen reception unit) configured to receive the synchronization signal and an optical-signal transmitting unit (pen control unit and a light-emitting diode) configured to transmit the optical signal in synchronization with the synchronization signal received by the receiving unit.

Abstract: An interactive system includes a transmitter (light-emitting pen) configured to transmit an optical signal and a projector. The projector includes a signal-intensity setting unit in which intensity information of a synchronization signal is set, a signal-intensity control unit (light-emission control unit) configured to control the intensity of the synchronization signal on the basis of the setting of the signal-intensity setting unit, a synchronization-signal transmitting unit (infrared-light emitting unit) configured to transmit the synchronization signal, and an image pickup unit configured to pick up an image of the optical signal transmitted from the transmitter. The transmitter includes a receiving unit (pen reception unit) configured to receive the synchronization signal and an optical-signal transmitting unit (pen control unit and a light-emitting diode) configured to transmit the optical signal in synchronization with the synchronization signal received by the receiving unit.

Abstract: A projector includes: an illumination device that emits illumination light; a light modulating device that modulates the illumination light on the basis of an input image signal; and a cooling device that cools the light modulating device according to a light amount of the illumination light.