Abstract: A motion capture system includes a motion capture detecting device with sensor coils that are sequentially selected by a control section. Signals are communicated between respective input coils of input elements of an input device and the sensor coils by electromagnetic coupling. The signals received by each of the selected coils are detected by a detecting section. Three-dimensional coordinates and directions of each of the input elements are calculated by a control section so that the input elements become continuous, based on the detected signals by the detecting section.

Abstract: A position detecting apparatus transmits position detecting signals from internal and external transmission coils, which are electrically connected to each other and are wound in opposite directions. The signals are transmitted to a position indicator that is housed within a pen-shaped input member. Since the internal and external transmission coils are wound in opposite directions, the position indicator can be efficiently excited in the entire area of a sensor unit including the end portion thereof. The position indicator receives the position detecting signals and transmits position indicating signals indicating a position. Sensor coils receive the signals from the position indicator. The position detecting apparatus detects the position of the position indicator based on the signals detected by the sensor coils.

Abstract: A position detection system includes a position pointer and a position detector. The “blind” area in which a position pointed to by a position pointer is undetectable is minimized. A transmission coil selector selects one of a plurality of transmission coils. A signal is generated by a transmission signal generator and supplied to a selected transmission coil. The selected transmission coil transmits the signal to the position pointer. A reception sensor coil selector selects a plurality of sensor coils. A position-indicating signal transmitted from the position pointer is received by each selected sensor coil, and a position pointed to by the position pointer is calculated from the received position-indicating signals. The position detection system loop coils are part of a resonant LC transmission circuit and are excited with a pulsed carrier signal to maximize the strength of the transmission signal, while dissipating relatively little power.

Abstract: A low-voltage drive circuit for driving a sensor coil in a coordinate input device at a constant current includes a DC coupling capacitor and a constant-current output bias circuit unit. The DC coupling capacitor is provided between an output of a constant-current output drive circuit unit and a sensor coil. The constant-current output bias circuit unit controls a DC bias voltage of the output of the constant-current output drive circuit unit to be a midpoint potential of an operating voltage range for the constant-current output drive circuit unit. The constant-current output drive circuit unit may include a drive source circuit segment and a drive sink circuit segment that function as a complementary constant-current circuit unit. Preferably, the drive source circuit segment and the drive sink circuit segment are connected to respective constant-current output bias circuit units.

Abstract: A reference circuit having a variable-impedance function for reducing current consumption is provided. By switching an output impedance of the reference circuit so that the output impedance is large when transmitting a high-frequency signal to a sensor coil, and the output impedance is small when receiving a response signal from the sensor coil, current consumption is reduced. The reference circuit includes a loop gain adjusting circuit having a switch for switching a gain. The magnitude of the output impedance of the reference circuit is switched by opening and closing the switch to switch the gain.

Abstract: A motion capture system includes a motion capture detecting device with sensor coils that are sequentially selected by a control section. Signals are communicated between respective input coils of input elements of an input device and the sensor coils by electromagnetic coupling. The signals received by each of the selected coils are detected by a detecting section. Three-dimensional coordinates and directions of each of the input elements are calculated by a control section so that the input elements become continuous, based on the detected signals by the detecting section.

Abstract: A low-voltage drive circuit for driving a sensor coil in a coordinate input device at a constant current includes a DC coupling capacitor and a constant-current output bias circuit unit. The DC coupling capacitor is provided between an output of a constant-current output drive circuit unit and a sensor coil. The constant-current output bias circuit unit controls a DC bias voltage of the output of the constant-current output drive circuit unit to be a midpoint potential of an operating voltage range for the constant-current output drive circuit unit. The constant-current output drive circuit unit may include a drive source circuit segment and a drive sink circuit segment that function as a complementary constant-current circuit unit. Preferably, the drive source circuit segment and the drive sink circuit segment are connected to respective constant-current output bias circuit units.

Abstract: A current feed circuit for feeding a high-frequency current to a plurality of sensor coils in a coordinate input device includes a high-frequency signal transmitting circuit for generating a high-frequency current corresponding to a high-frequency signal input; a plurality of driver transistors, each being provided between the high-frequency signal transmitting circuit and each of a plurality of sensor coils for transmitting the high-frequency current to the corresponding sensor coil; and a plurality of switches, each being provided with respect to each of the plurality of driver transistors for turning on/off the corresponding driver transistor.

Abstract: A reference circuit having a variable-impedance function for reducing current consumption is provided. By switching an output impedance of the reference circuit so that the output impedance is large when transmitting a high-frequency signal to a sensor coil, and the output impedance is small when receiving a response signal from the sensor coil, current consumption is reduced. The reference circuit includes a loop gain adjusting circuit having a switch for switching a gain. The magnitude of the output impedance of the reference circuit is switched by opening and closing the switch to switch the gain.

Abstract: A three-dimensional information sensor device is disclosed in which sensor coils thereof are sequentially selected by a control section. Signals are communicated between indicating coils of a three-dimensional information indicating device and sensor coils by electromagnetic coupling. The signals received by each of the selected coils are detected by detecting means. The position and the direction of the indicating device in a three-dimensional apace are calculated by control means based on the detected signals.

Abstract: An orientation-detecting apparatus has an orientation-designating device which is provided with a plurality of orientation-designating coils whose coil planes face in different directions. Each of the orientation-designating coils forms a resonance circuit having a resonant frequency different from the resonant frequencies of the other resonance circuits. An orientation-detecting sensor includes a plurality of orientation-detecting coils L, M, L′, and M′ which are radially disposed and are electromagnetically coupled to the orientation-designating coils. The orientation-designating device is placed at the center position O of the orientation-detecting sensor. By transmitting and receiving signals between the orientation-designating coils and the orientation-detecting coils L, M, L′, and M′, orientations of the orientation-designating device in three-dimensional space are detected as absolute values.

Abstract: The invention relates to a point detecting device and a method for providing coordinate information which is indicated by a pointing device. This point detecting device is adapted for a large scaled system which is required to be operated at a low cost and at high accuracy. The point detecting device transmits signals from both ends of the loop coil arrangement towards the pointing device, and/or receives at both ends the signals generated by the electromagnetic function between the loop coil arrangement and the pointing device. The errors owing to the variations caused in the signal level and phase in response to the propagation constant of the loop coil arrangement can be reduced by adding the received signal pair.

Abstract: A position detecting device for calculating coordinates of the position indicator rapidly and accurately to provide data related thereto without using any high sampling rate and high speed arithmetic operation is provided. The position detecting device performs a signal processing for providing coordinates of the pen based upon signals (50) from a sensing unit, which has a large number of loop coils disposed in parallel with respect to one another and generates said signals due to electromagnetic effects between the coils and a position indicator (input pen ) (3) disposed on these coils.

Abstract: A coordinate detecting apparatus with a display unit of a type having a separated control unit constituted for the purpose of improving the handling facility of the coordinate detecting apparatus with the display unit, lowering the frequency for transferring data about the contents to be displayed, enabling the circuit for the display control means to be freely designed and also enabling the coordinate detecting apparatus to be connected to an existing computer body. The coordinate detecting apparatus with the display unit is supplied with power from a power source for a control unit, data about the contents to be displayed is supplied from the control unit to the coordinate detecting apparatus with the display unit via one integrated cable while being compressed to form a graphic control signal, the data about the contents to be displayed is restored in the coordinate detecting apparatus with the display unit and the aforesaid function is given to the interface board.

Abstract: With a view to providing a coordinate detecting device whose operation can be checked after the housing thereof is assembled, check pin guide holes are provided in a portion of the housing, and check terminals are provided in a portion of a circuit board, the latter portion corresponding to that of the check pin guide holes, the check terminals being used for extracting signals input from and output to an external apparatus. The coordinate detecting device includes: a circuit board; a housing in which the circuit board is housed; and a cable extending from the circuit board to the outside of the housing, the cable being used to electrically connect the circuit board to the external apparatus. Storage elements for storing input data are provided. A covering label is attached to cover the check pin guide holes. The check pin guide holes and the check terminals are provided near a status lamp.