Dainippon Screen Mfg. Co., Ltd.

Dainippon Screen Seizo Kabushiki-kaisha

Masamichi Cho

Kunio Tomohisa

Yasuo Kurusu

Takashi Sakamoto

Kiyoshi Maeda

Motonobu Kawabata

Hiroyuki Shirota

Koichi Isono

Shinichi Nagata

Nobuhiro Takita

Akihiro Nomura

Katsuki Fukuyama

Thouru Yonezawa

An image recording apparatus includes a scanning part for recording a plurality of unit images individually on a plurality of recording media, the plurality of unit images being to be superimposed on each other to form a single objective image. The scanning part causes the plurality of unit images to be in different positions. Defects appear in different positions of the plurality of unit images, and are prevented from coinciding with each other in the objective image.

Apparatus for and method of recording image

A first data rate detecting portion sends a first data transfer rate on a first interface, and a second data rate detecting portion sends a second data transfer rate on a second interface, respectively, to a CPU. The CPU compares the first and second data transfer rates and sets a connection state of a selector so that the image recording onto a photosensitive material is made at a high speed. The CPU also respectively determines the optimal rotation speeds of a polygon driving motor and a roller driving motor from the first or second data transfer rate, and rotates the polygon driving motor and the roller driving motor at the optimal rotation speeds. Then, when image data is inputted, an image is recorded on the photosensitive material.

Image recording apparatus capable of adjusting an image recording speed

Beam position sensors detect deviations of a light beam from target positions defined at both sides of a recording drum. Predicted total deviations of light beam from the target positions are calculated as a function of beam position signals detected by the beam position sensors. A piezoelectric element of a sub-deflector is actuated in response to the predicted total deviations. The light beam deflected by a main deflector scans the target positions on a recording medium.

Method and apparatus of detecting deviation of scanning line of light

Experiential gradation correction curves for sample images are prepared. By analyzing the experiential gradation correction curves and accumulated density histograms of the sample images, two points (Y.sub.1, Q.sub.1) and (Y.sub.2, Q.sub.2) are specified, where Y.sub.1 and Y.sub.2 are values of accumulated occurrence and Q.sub.1 and Q.sub.2 are halftone dot percentages for image reproduction. The values Y.sub.1 and Y.sub.2 through an accumulated density histogram of an original image whose gradation is to be corrected. A gradation correction curve Q=G(x) is determined so as to pass through the two points (x.sub.1, Q.sub.1) and (x.sub.2, Q.sub.2).

Method of generating gradation correction curve for correcting gradation

A method and apparatus for detecting the shape of a beam spot on a scanning plane in a scanning optical system having a constant scanning speed. When a relative moving speed of the light beam is not known beforehand, four slits are used to detect intensities of light passing through the slits. Three of these slits have different angles of inclination with respect to a scanning direction, and the remaining slit has the same angle of inclination as one of the three slits. When the moving speed of the light beam is known in advance, the first-mentioned three slits are used. The moving speed of the light beam is derived from a time lapse between signals detected through the two slits having the same angle of inclination. Once the moving speed of the light beam is known, periods of movement required for the light beam to traverse the three slits having different angles of rotation are obtained on the basis of detection signals relating to these slits. Then, distances of movement required for the light beam to traverse the three slits are derived from the periods and scanning speed, respectively. The three distances of movement thus obtained are used in determining the beam spot shape. Where knife edges are used instead of the slits, the above operation is carried out after differentiating signals detected through the knife edges.

Method and apparatus for detecting beam spot shape

In an image recorder, a recording photobeam and a reference photobeam are periodically deflected by a polygon mirror in a main scanning direction. The recording photobeam is supplied to a photosensitive film while the reference beam is supplied to a transparent grating scale on which a transparent area and an opaque area are formed. The combination boundary of the transparent area and the opaque area has a portion parallel to the main scanning direction. The reference beam transmitted through the transparent area is detected, and the photobeams are deflected in a subscanning direction by an acoustic-optical deflector in response to the detected optical amount of the reference photobeam.

Scanning beam control system and optical scale structure useful thereto

Apparatus for reproducing a scanned picture with sharpness emphasized. A scanner is provided for scanning a picture to be reproduced in two directions perpendicular to one another and for generating and recording signals representing the scanned picture. There is a sharpness emphasizing device for summing and averaging a plurality of picture element signals aligned in one of the scanning directions in the vicinity of a scanning point in the picture being scanned and recorded to generate values and then summing and averaging a plurality of the resulting summed and averages picture signals aligned in the other scanning direction in the vicinity of said scanning point to generate further values and then producing a recording signal equal to S+k(S-U), where k is a constant chosen to enhance a particular characteristic of the scanned picture, S is the sharp signal component at said scanning point and U is a generated unsharp signal. Finally, there is a device for receiving the recording signal and for employing it to reproduce the scanned picture.

Reproduction picture sharpness emphasizing method and apparatus

An image signal is filtered in one or two-dimensions for obtaining an unsharp signal in a detail emphasis process of an image reproduction system. A one-dimensional image signal filtering is carried out in one of the main and sub-scanning directions so that the first K image signals and the other K image signals out of 2K image signals are respectively summed to obtain first and second sum signals, which are subjected to a cumulus computation to obtain a filtered signal U.sub.2 expressed by: ##EQU1## for (2K-1) image signals d.sub.i (i: K, K-1, . . . 1, 0, -1, -k+2 In this regard, a cumulus computation refers to computation expressed by p.sub.n -Q.sub.n +R.sub.n-1 =R.sub.n, wherein P.sub.n is an addition signal and Q is a subtraction signal where n is the input order of each of the signals and R.sub.n-1 is the result of the previous computation. By filtering the thus-obtained (2K-1) one-dimensionally filtered signal U.sub.2i (i=K, . . . 1,0, -1, scanning direction factors in the same manner, a two-dimensionally filtered signal W.sub.2, expressed by: ##EQU2## is obtained to be used as an unsharp signal for the abhove-mentioned detail emphasis process. In this connection, the number 2K-1 corresponds to a mask size, which can be arbitrarily determined by adjusting the value K. By carrying out the cumulus computation in a plurality of stages, a weight coefficient of multidimensional function with respect to the value i can be imposed on image signals.

Image signal filtering

A halftone image recording apparatus has an interpolating function for interpolating previously obtained first halftone pattern data in the main scanning direction to obtain second halftone pattern data. Comparisons between input image signals and the second halftone pattern data per pixel are made to expose a photosensitive material on the basis of the results of the comparisons thereby to create a halftone plate. Through the interpolation, the recording density in the main scanning direction is increased in response to the rate of increase in pixel density.

Halftone image recording method and apparatus

Image signals inputted from an input device are subjected to A-D conversion through an A-D converter to be stored in memory by at least an adjacent pair of pixels. The pair of pixels are interpolated by interpolation arithmetic circuit so that generated interpolation data and data on the pair of pixels are ordered under control by a timing controller to be outputted.

Method and apparatus for interpolating image signals

An image signal of the input and/or the output side is (are) multiplied by a shading compensation signal obtained from the output signal of a low-pass filter employed in a PLL circuit or a greating signal multiplying means.

Method and system for compensating for a shading phenomenon

In a method for emphasizing sharpness in picture scanning recording time in a picture reproducing machine a central picture signal obtained by scanning an original picture according to the scanning sequence and peripheral picture signals of the central picture signal which are appropriately weighted are added to the central signal and averaged to obtain vignette signals, and they are appropriately calculated for emphasizing sharpness of the picture signal. In the method as the peripheral picture signals desired numbers of continuous picture signals are selected by centering the central signal in the main scanning and the sub-scanning directions independently.

Method for emphasizing sharpness in picture scanning recording time in a

Calibration and shading correction of output image data of a photosensor array are carried out simultaneously by varying the gain and offset value of a photosensor amplifier in synchronism with input scanning of an original. The variation of gain and offset is made as a function of a first density reference voltage obtained by scanning a first density reference board, a second density reference voltage obtained by scanning a second density reference board and ideal voltages corresponding to the first and the second density reference voltages.

Growing community of inventors

Kyoto, Japan

Masamichi Cho