Matsushita Electric Industrial Co., Ltd.

Matsushita Research Institute Tokyo, Inc.

Yukifumi Tsuda

Hiroaki Kotera

Kunio Yoshida

Hiroyoshi Tsuchiya

Heijiro Hayami

Yuji Maruyama

Yoshimitsu Kanno

Hiroto Toba

Kazutoshi Ikegaya

Kunio Sannomiya

Tsutomu Shibata

Motohiko Naka

Ryuzo Kan

Teruo Fumoto

Nobuhiro Araki

Ryuzo Itabashi

Haruko Sugita

Kunjo Sannomiya

Takumi Seto

A system for inspecting a condition of parts packaged on a printed-circuit board. The inspection system includes a position detecting device to receive scattered light due to illumination of the printed-circuit board with a laser beam and convert the received scattered light into a position signal. This position signal is used for obtaining luminance data and at least two height data of the parts on the printed-circuit board. Proper height data of the parts is determined on the basis of the difference between the two height data. The inspection system determines the package condition by comparing the final height data with a predetermined reference data.

System for optically inspecting conditions of parts packaged on substrate

A beam of light is applied to a surface of a circuit board provided with at least one solder portion. The light beam scans the surface of the circuit board. Height data are derived from a portion of the light beam which is scattered at the surface of the circuit board. The height data represent a height of a currently-scanned point of the surface of the circuit board. The height data are accumulatively added for the solder portion. A variation in the height data is calculated. The accumulative addition of the height data is executed and suspended in response to the calculated variation in the height data. A decision is made as to whether the solder portion is acceptable or unacceptable on the basis of a result of the accumulative addition.

Apparatus for inspecting solder portion of a circuit board

A printed-circuit board inspection apparatus for checking the condition of each circuit component mounted by soldering on a printed-circuit board is disclosed in which a luminance signal obtained from the reflected light scattering from the printed-circuit board being illuminated is converted through a given threshold level to binary signals, then the binary signals and mask data are processed to calculate the ratio of an area represented by the number of binary '1' signals to an area represented by the number of binary '0' signals, and the soldering condition of the component is judged based on the area ratio. With this arrangement, the inspection is not negatively influenced by the misalignment of the component with a mating soldering land, is capable of judging the amount of solder, and can be performed automatically and efficiently. The binary signals may be converted into code data by assigning a code '1' or '0' to each of a plurality of split masks set on each soldering land, depending on the largeness of the area in which the number of binary '1' signals '1' is larger than the number of binary '0' signals or vice versa. In this case, the judgment of the soldering condition is made by comparing the code data with code patterns contained in a predetermined code table.

Electro-optical inspection apparatus for printed-circuit boards with

A linescan apparatus for detecting salient pattern on a surface of a product comprises: a laser light source for continuously emitting a laser beam; a polygon mirror for reflecting the laser beam; a drive for rotating the polygon mirror to scan said laser beam; an f.theta. lens arranged such that the linescan laser beam strikes against the plane perpendicularly; a carrying device for moving the product in the direction substantially perpendicular to the plane; a mirror for reflecting the linescan laser beam reflected at a surface of the product to direct the linescan laser beam to the polygon mirror through the f.theta. lens, the mirror being positioned apart from the second plane; and a beam position detector for detecting unidimensional position of a spot mede by the linescan laser beam projected thereon from the mirror via the polygon mirror. This linescan apparatus provides three-dimensional data of a surface of the product. The detected position signal is compared by reference data for inspecting the product. An linescan apparatus further comprises second beam position detector and an averaging circuit for averaging outputs from first mentioned and second beam detectors.

Linescan apparatus for detecting salient pattern of a product

Color correction method and processor for improving the quality of color reproduction in a color picture recording unit or display unit in a color copy machine, a color facsimile or a color printer. A memory means previously stores in a table values of secondary color correction image data used for recording corresponding to values of primary image data produced through a color scanning of a color picture. The secondary color correction image data are read out from the table by addressing signals formed from the three color components of the primary image data. Data bits for the addressing signals of the three color components of the primary image data are assigned unevenly depending on the contribution factor of each in forming the three color components of the secondary color crrection image data, thereby reducing the required number of addressing bits and associated memory.

Color correction processor with memory addressed by color component

A color image duplicating device comprises a function generator (60) for generating a plurality of functions of n degree wherein elements of color separated data (201, 202, 203) from a color original (1) are variable, a storing device (66) for storing predetermined coefficients, and an arithmetic unit (61, 62, 63) for performing the calculation to find the product and sum of outputs from the function generator (60) and that of the storing device (66). An output from the arithmetic unit (61, 62, 63) is applied to a color recorder (3) to form a color duplicated image.

Color image duplicating system

To overcome the tendency of the recording head of a dot printer to become inoperative in a range below a threshold level, a gray scale input signal is modulated with an oscillating signal so that the modulated signal oscillates above and below the threshold level to reproduce halftone values below the otherwise inoperative range.

Dot printer for reproduction of halftone images

Light beams scans patterns of a subject copy, being reflected therefrom, and being converted into pulsating electrical signals. Color borders between two different colored patterns are detected based on the pulsating signals. On the other hand, a color of a predetermined scanned line following each of the color borders is sensed for determining the sensed color as a color between the adjacent color borders.

Method of and a system for color separation

A color print painted with different colors C.sub.i (i = 1, 2 . . . n) is scanned by a color scanner along a plurality of successive line paths to generate a set of electrical signals each representing the intensity of the spectral components of the light reflected from an elemental area of the print. A macroscopic color separator is provided to generate a set of electrical signals each representing the average spectral intensities per unit area of the print. A data processor is used to compute the probability P(C.sub.i) from the data obtained from the macroscopic color separator and a set of mean spectral intensities exhibited by the color samples with which the print is painted by artisans. In accordance with the Bayes' Rule, the processor then executes computation of the product of P(C.sub.i) and the conditional probability of occurrence of elemental color spectral intensities given that the elemental area being scanned belongs to a particular color sample, using the data received from the color scanner as it scans the print.

Color separating method and apparatus using statistical techniques

An ink ejection system of the invention includes an electrical circuit generating sinusoidal wave pulses and a liquid applying unit operable to discharge the liquid in pulsed jets in response to the sinusoidal wave pulses. The circuit comprises means for generating a sinusoidal signal of constant amplitude and frequency higher than the highest instantaneous frequency of a video signal, and means for modulating the amplitude of the sinusoidal signal in accordance with the video signal to generate a signal containing no harmonic components.

Ink injection type writing system using amplitude-modulated electrical

A two-valued object such as black-and-white textural or pictorial material is repeatedly scanned aong each of a plurality of line paths within the object to produce an image signal which is representative of a series of black and white runs or areas within the line path. The length of black or white run or 'run length' is sampled by clock pulses and translated into a binary code and transmitted bit by bit at the line scan rate to a receiver station. A vertical sync pulse is inserted at the end of the (n-1)th run length wherein n represents the number of run lengths within the image signal so that the last run length is skipped. The last run length so skipped at the transmitter is reconstructed at the receiver during the time interval of the vertical sync pulse.

Facsimile signal transmission system

A colored original which is painted with a plurality of predetermined colors is scanned along each of a plurality of line paths each of which can be divided into one or more colored line segments. Encoders are provided to characterize each of the line segments by a corresponding first code representing the color of the segment and a second code representing the run length of the segment. The first and second codes are sequentially recorded in a data file memory. The recorded information is repeatedly retrieved from the memory and transferred to a shift register. Line segments carrying the same color within each line path are detected by comparing the corresponding first code with a specified code. The second code is sequentially decoded into run lengths which are accumulated to measure the position of color transitions relative to the colored original. A video signal is generated upon occurrence of coincidence between the first code and the specified code. A photographic film is scanned by a light beam modulated with the video signal to develop an image carrying the detected color on a specified portion of the film in correspondence with the specified code. The codes to be specified are sequentially changed to detect the line segments of different colors in a predetermined sequence within the period of the scanning. In synchronism with the code change, the shift register is shifted to recirculate the data.

Method and apparatus for separating, combining and rearranging colored

A photographic image pick-up and coding system of run-length type which includes a correction circuit for preventing erroneous operation of the system even when the system is subjected to unwanted external disturbances such as noises and fluctuations of the voltage of the power source.

Photographic image pick-up and coding system of run-length type

A transmitter for a facsimile system of run-length type, which comprises a facsimile signal generator, a pulse generator for producing a sampling pulse train, a sampler for sampling each of the space and mark signals with the sampling pulse train, and a coder for converting the sampled space and mark signals into successive binary code signals, the coder including at least two counters and means for selectively operating the two counters. A receiver for facsimile system of run-length type, which comprises a timing pulse generator for producing timing pulses, a demodulator for demodulating modulated binary code signals, a decoder for decoding the binary code signals into binary codes each representing a run-length of one of mark and space signals, a memory circuit for memorizing the binary codes, said memory circuit including at least two registers and means for selectively operating the two registers, and a reconverting circuit for reconverting the binary codes from the memory circuit into one of the mark and space signals.

Growing community of inventors

Kawasaki, Japan

Yukifumi Tsuda