Nec Corporation

Kazuo Ichinokawa

Yoichi Sato

Takayuki Yokoyama

Fumio Ando

Tadashi Ohtsuka

Tadashi Otsuka

In an audiovisual communication, a first high fram rate video signal is derived from a motion image and converted to a low fram rate low resolution multiframe signal. A second high frame rate video signal is derived from an still image and converted to a single frame high resolution signal. Because of the low frame rates, the frequencies of the low and high resolution signals are within the range of frequencies of a telephone exchange line. A switching matrix is provided to sequentially couple both the low and high resolution signals to a transmission line in response to a mode select signal. The single frame high resolution signal is stored into a memory at the receiving end and repeatedly retrieved out of the memory into a display through the switching matrix.

Videotelephone apparatus for transmitting high and low resolution video

A frequency coupling position coordinates determination apparatus includes sheet means on which N (positive integer) one-turn coils for detecting a magnetic force and M (less than N) signal lines to which at least one predetermined one-turn coil of the N one-turn coils is connected are arranged, and detecting means for detecting the amplitudes of currents respectively flowing through the M signal lines.

Frequency coupling position coordinates determination apparatus

A novel digitizer operable on an optical digitization basis comprises a transparent flat plate as a light active surface located on a graphic data recording medium, and a cursor functioning as an optical recognition device movable on the transparent flat plate. A predetermined coordinate correlative pattern is described on or in the transparent flat plate with a fluorescent paint. The cursor comprises a positioning arm provided on the outer periphery thereof to visually trace a data location on the recording medium in accordance with a movement of the cursor to effect positioning of the cursor with respect to the data location, an optical system including a light source, an optical filter assembly, and a light focusing lens etc., and a CCD sensor unit to sense light emitted from a partial pattern which falls within a predetermined limited visual range of the pattern. By irradiation of the pattern, fluorescent light is emitted therefrom. The optical digitizer is operative to determine position coordinates of a graphic data on the recording medium in accordance with an projected image of fluorescent light sensed by the sensor unit. Thus, such an implementation makes it possible to realize a small-sized, high accuracy digitizer completely free from influence of electromagnetic wave noise.

Optical digitizer

A manual image scanning system is operative to read image data of figures or letters depicted on a sheet of paper based on manual operation to input them to a personal computer for data processing. The manual image scanning system comprises a data tablet or a digitizer in which magnetostriction pulses propagate, the data tablet being adapted so that a sheet of paper on which a figure is drawn is placed thereon, and a compact manual image scanner adapted to be manually movably placed on the data tablet, the manual image scanner having a first function to recognize the figure drawn on the paper to produce data indicative of image of the figure, and a second function to sense a position of the scanner to produce data indicative of the position of the scanner. The scanning system further comprises high speed image processing circuitry responsive to the image data and the position data from the scanner to compute coordinates of the scanner on the data tablet, thereby recognizing which portion of the data tablet the image data corresponds to. Thus, this system can sufficiently exhibit features provided by the data tablet and the optical figure recognition device.

Growing community of inventors

Tokyo, Japan

Kazuo Ichinokawa