An electric circuit is to be incorporated in a pointing device (such as a computer mouse) which is used in combination with a data processing system (such as a computer) so as to reduce the energy consumption of the pointing device without affecting the original functions and efficiency thereof and thus permit the pointing device to fit into a system wherein electric consumption is of vital importance. The electric circuit includes a timing control circuit and a noise-suppressing sampling circuit which controls the operation of the energy consuming elements of the pointing device according to the movement of the pointing device. The noise-suppressing circuit can distinguish movement signals from noise signals, thus suppressing the interference due to noise and further reducing the energy consumed by the pointing device.
A computer pointing device includes an interface for communicating to a computer in response to a user input. The pointing device includes an inaudible moveable input that is activated by the user. The pointing device includes a resilient member with at least one electrical contact. The moveable input cooperates with the resilient member to engage and disengage the electrical contact from an interface electrical contact. Engagement between the electrical contacts is silent or inaudible in response to user input to the moveable input. The pointing device also includes a switching mechanism that converts the inaudible engagement of the electrical contacts into an audible engagement.
A pulse-type driving device for driving a plurality of light emitting diodes includes a power source providing a DC voltage, a pointer control circuit including a pulse output terminal for outputting pulses therefrom. A plurality of sets of detecting circuits each of which includes one of the light emitting diodes, a phototransistor, and a transistor. The light emitting diode emits light to activate the phototransistor which in turn triggers the transistor to output a signal to the pointer control circuit. A constant current source is connected between the pointer control circuit and the light emitting diodes and provides constant current to energize the light emitting diodes.
A coordinate inputting apparatus has a separating circuit, a cable and a position indicating pen. The separating circuit has a low pass filter for removing an alternating current component from a signal transmitted to a signal line and a band pass filter for passing only a position information signal in a predetermined frequency band with respect to the signal transmitted to the signal line. The cable is constructed by a signal line, a switching signal line and a ground line. The signal line is used to supply power to the position indicating pen and transmit a detecting signal from the position indicating pen to each of an X-coordinate detecting circuit and a Y-coordinate detecting circuit. The position indicating pen has a low pass filter for removing an alternating current component from a signal transmitted through the signal line and a band pass filter for passing only a position information signal in a predetermined frequency band. A signal transmitting system of this coordinate inputting apparatus and other coordinate inputting apparatuses are also shown.
A computer pointing device includes an interface for communicating to a computer in response to a user input. The pointing device includes an inaudible moveable input that is activated by the user. The pointing device includes a resilient member with at least one electrical contact. The moveable input cooperates with the resilient member to engage and disengage the electrical contact from an interface electrical contact. Engagement between the electrical contacts is silent or inaudible in response to user input to the moveable input. The pointing device also includes a switching mechanism that converts the inaudible engagement of the electrical contacts into an audible engagement.
The present invention includes a light receiving unit having a first and second light receiving element which receive light emitted from a light emitting element via slits formed at a rotary disk and respectively generate detection signals whose phases differ from each other substantially by 90.degree.. A first waveform shaping circuit compares the detection signal from the first light receiving element with a reference value and generates a first detection output of a rectangular waveform. A second waveform shaping circuit compares the detection signal from the second light receiving element with the reference value and generates a second detection output of a rectangular waveform. A peak hold circuit receives the detection signal from the first light receiving element and holds the peak value thereof. A reference value generating circuit generates the reference value depending on the peak value held at the peak hold circuit.
