U.S. patents available from 1976 to present.
U.S. patent applications available from 2005 to present.

Icon_funbox Did You Know...

...that while attempting to develop a super strong glue, 3M employee Spencer Silver accidentally developed a glue that was so weak it would barely hold two pieces of paper together? However, his colleague Art Fry needed the glue. Fry sang with his church choir and marked the pages of his hymnal with small scraps of paper that often fell out. He used Silver's glue to hold the papers in place. Today we call this invention Post-it Notes.

Newsletter  PatentStorm News

Make the Most of Our Site

See this month's Top Inventors and Most Cited Patents.


Registered users: Manage your profile.


Class 178/20.02 - Electrical filter or multiplexer

Subclass of Class 178 - Telegraphy
Definition: Subject matter including an electrical element that can
No. of patents: 55
Last issue date: 02/13/2007

NumberTitleIssue Date
7176907Device and method for pointer system of digitizer tablet
The invention, an improved device and method for the pointer system of a digitizer tablet, is to repetitiously emit signals sequentially from a specific set of inductive loop when the position pointed by the wireless pointer device is located within a range formed b...
7148883Information recording and reproducing apparatus
When a point on a tablet is designated by a marker, a recording indication signal is on, and recording of sound data is started. When the marker is released from the tablet, the recording indication signal is off, the recording of the sound data is finished, and coo...
7136049Input apparatus
An input apparatus of the resistive type that is thinner and more durable is provided. The apparatus includes a first substrate having a conductive film on which a plurality of slits are formed in stripes, and a second substrate spaced apart from the first substrate...
7132612Orientation sensing device for use with coded marks
A sensing device for generating orientation data when positioned or moved relative to a surface, the orientation data being indicative of an orientation of the sensing device relative to the surface, the surface having coded data disposed upon it, the coded data bei...
7105753Orientation sensing device
7030782Position detector
A position detector is provided for detecting the relative movement of first and second members which are mounted for relative movement along a measuring path. One of the members comprises a magnetic field generator for generating a magnetic field and the other memb...
7006087Method and apparatus for describing solid shapes, and CAD/CAM system which employs the method
Disclosed is a solid shape describing apparatus provided with a function for defining both absolute coordinate system and floating coordinate system, a function for describing a relationship between the absolute coordinate system and the floating coordinate system, ...
6907374Self-calibrating sigma-delta analog-to-digital converter
A self-calibrating sigma-delta converter (SCADC) functions in a calibration mode and in an operational mode. In the calibration mode, a test circuit of the SCADC generates test signals that are periodic rectangular voltage waveforms. Each test signal has a dc compon...
6906702Coordinate input device and its control method, and computer readable memory
A device has a plurality of linear sensors which are arranged for at least one coordinate axis and detect the beam spot. The levels of detected data are measured by a sensor controller, and the measured levels are compared. Based on the comparison result, the detect...
6730863Touchpad having increased noise rejection, decreased moisture sensitivity, and improved tracking
An improved touchpad and measurement circuitry for enabling input to a computer or other electronic device. The system includes an X electrode, a Y electrode, a common sensing electrode, and a “water” electrode, wherein these four separate electrodes can be impl...
6353193Electronic whiteboard system and method
An eraser for use on an electronic whiteboard with a protrusion area on the erasing surface forming a convex area on the erasing surface for establishing a positive point of contact with the whiteboard; an electronic whiteboard system including such an er...
5844548Stable wireless pointing device for a tablet
A system for determining a position of a wireless pointing device relative to the plane of a conductor grid, by inducing currents in the conductor grid, includes a pointing device and a digitizer tablet on which is situated the conductor grid. The pointin...
5798756Coordinate detection device capable of obviating the need of forming closed loop in electrodes thereof
There is provided a coordinate detection device capable of preventing increase of development cost and reduction of yield and dispensing with additional investment for existing equipment. The coordinate detection device includes an LCD panel having electr...
5684277Coordinate input apparatus
A coordinate input apparatus which can attain an accurate coordinate input operation, includes a sensor for detecting an input variation. The vibration is amplified, and an envelope detection circuit generates the envelope of the amplified vibration. A ga...
5661269Position pointing device having resonant circuit with sequentially changed characteristics and combination thereof with position detecting device
A position pointing device for use with a digitizing tablet sequentially transmits plural different kinds of non-positional information to the tablet. The position pointing device varies a resonance characteristic of a resonance circuit in accordance with...
5608390Synchronous telemetry channel
The invention concerns pen-based computers, wherein a pen, or stylus, is positioned on a display of the computer, and produces a signal which allows the computer to detect the position of the stylus. The stylus produces a second signal, which is used as a...
5594215Wireless digitizer and stylus pen unit
A digitizer and stylus pen unit including a winding type conductor loop, a conductor pen or cursor, and a central processing unit, wherein when the signal input device is started to provide an oscillatory signal and a TX/RX control signal to a TX/RX contr...
5557076Cordless position detection apparatus
A cordless position detection apparatus includes a position detection area and a pointer. A plurality of conductors are arranged side-by-side in the position detection area. The position detection area has a selection circuit for selecting single conducto...
5539160Coordinate input apparatus and method
Oscillation applied to a tablet is sensed by a sensor on the tablet and a time delay from generation of the oscillation to the sensing thereof is measured, whereby distance from the oscillation source to the sensor can be measured. If this distance is mea...
5488024Selective acetylene hydrogenation
A catalyst composition comprising palladium, silver and a support material (preferably alumina) is contacted at a relatively low temperature (of up to about 60° C.) with a liquid composition comprising an effective reducing agent (preferably an alkali me...
5359156Integrated circuit for digitizer table with dedicated digital signal processor for improved noise immunity
A digital tablet of the type that multiplexes pen position signals has filtering and digitizing circuits arranged in separate channels for each of the signals that is to be multiplexed. The tablet pen is connected to receive an oscillator signal and the s...
5349139Architecture for communication of remote devices to a digitizing display
An architecture for communication of remote devices to a digitizing display includes a contact sensing mechanism and a position sensing mechanism whose outputs are multiplexed for transmission from the stylus to an antenna located proximate to the digitiz...
5345044Cordless digitizer using electromagnetic locating signals
In order to determine without ambiguity the grid sections on which the pointer is located in a cordless electromagnetic digitizer having x and y locating grids, a third, "phase" grid has conductors that form elongated, narrow open loops, spaced so that ea...
5245336Digitizer with overlapped loop pattern and peak phase recognizer
A digitizer comprising a microprocessor, a quartz oscillator, a cursor or stylus, an overlapped loop assembly, a peak phase recognizer, an analog/digit converter and other matching devices including multiplexers, amplifiers, filters and etc., wherein the ...
5239138Coordinate input apparatus
A coordinate input apparatus determines the coordinates of contact of a vibration pen with a vibration transmission plate by detecting vibrations from the pen through a vibration sensor. Constants required for measurement are generated in a constant deter...
5218174Low power cordless magnetic field digitizer with differential grid sensing and synchronous position demodulation
A digitizing system includes a tablet and a cordless pointing device including a plurality of data grid conductors in the tablet and a plurality of clock grid conductors in the tablet, all receiving a magnetic field signal transmitted by the pointing devi...
5160813Cordless digitizer local conductor phase reference system
In an electro-magnetic, cordless digitizer system wherein a transducer emits an AC magnetic field which is detected by a first grid of scanned parallel first wires in a tablet to provide positional data for the transducer in a first axis of a coordinate s...
5107079Position digitizer circuit for a moveable instrument
The invention is a digitizer circuit in a peripheral system for a computer comprising a moveable instrument and a planar grid in which an excitation signal in one of said instrument and grid generates an induced signal in the other one of said instrument ...
4963703Coordinate determining device using spatial filters
A digitizing tablet is disclosed in which two sets of circuitous conductive lines form grids each connected at one end to a surrounding conductive loop. All outputs are measured from the conductive loop as a multiplexor sequentially grounds the grids one ...
4928256Digitizer for position sensing
Apparatus and method for determining position, tilt and offset of a pointer with respect to a grid of parallel conductors with which it is coupled by obtaining measured responses between each of a group conductors and the pointer and fitting an expression...
4918263Co-ordinate measuring system
A co-ordinate measuring system determines the position of a coil member relative to a grid member defined by a set of equidistant, parallel conductors associated with a co-ordinate axis of the system. The system includes a switching circuit that is constr...
4905174Optical coordinate input apparatus
In an optical coordinate input apparatus, an insect or mud may disturb optical coordinate input operation for a main computer. To avoid such a problem, light emitting element arrays and light receiving element arrays are arranged opposite to each other, a...
4853499Ground switching technique for silkscreened digitizer grids
A method and associated circuitry for use in an electromagnetic digitizer having a plurality of first grid conductors connected from a first multiplexer controlled by a first enable input to ground and a plurality of second grid conductors connected from ...
4837716Twin-rate charging and discharging proportional type cursor position determining device
An electromagnetic digitizer which applies twin rate charging and discharging proportional to determine center position of a cursor. It makes use of the largest and second largest voltages detected by sense rings, the second largest is charged for a stand...
4833279Digital computer writing board
A digital computer writing board making use of the piezoelectric characteristics by means of a soft piezoelectric film material to convert a physical pressure into an electrical signal, which is utilized to form fine electric polar lines of high resolutio...
4820886Low-cost, high-accuracy digitizer signal acquisition apparatus and method
An improvement to position digitizing devices wherein sensed response voltages caused by the interaction of a movable instrument relative to conductors beneath a planar surface are converted to digital form and digitally processed to determine instrument ...
4734546Digitizer system with loopback conductor grid
In a digitizer system, adjacent conductors in pairs are looped through four quarter sections of a grid active area in such a way that the unexcited polarities of the pair are different in each quarter section. A coil in a pen tip is moveable relative to t...
4728944Coordinate position digitizing system
A coordinate position digitizing system to be used with a cathode ray tube, comprises a position determining plate having a plurality of conductors extending parallel with one another at regularly spaced intervals, and driving means for supplying a consta...
4723299Noise eliminating circuit for a graphical input terminal
A noise eliminating circuit is provided for a graphical input terminal having an input unit which generates electrical signals when a stylus is used to write on a surface of the unit. The electrical signals correspond to information written on the surface...
4717793Graphic input device
A graphic input device has a tablet surface with two groups of conductor loops orthogonally arranged below an input surface. These conductors are scanned sequentially to detect an inductive coupling with a winding in a stylus or pen which is writing on th...
Sign InRegister
forgot password?