Dainippon Screen Seizo Kabushiki-kaisha

Takeshi Yoshimoto

Masanari Tsuda

Masakatsu Yokoi

Yoshikazu Masuda

Seiji Okazaki

Hideki Hiraoka

Tsutomu Harada

Yoshihiro Taniguchi

A method for obtaining a desired picture with high quality by scanning a rotating recording drum by a scanning light beam, which produces images on the drum through a projection lens, receiving the said images being reflected from the drum through the projection lens on an image sensor, detecting variations of diameter of the drum per each rotation from variations of intensity of light of the images, whereby position of the projection lens being movable along the normal direction of the drum is automatically adjusted against machining errors of the drum diameter and variations of the said diameter caused by changes of its surrounding or any other reasons, temperature, so that variations of imaging points of the scanning light beam can always be within a range of depth of a focus of the projection lens.

Method for focus adjustment of a picture scanning and recording system

A method for automatically correcting variations in intensity of laser beams output from a projection lens, which variations occur due to variations of a spectrum pattern of optical fibers when their tip portions move, by paying attention to each of focal points of an image sensor which focal points correspond respectively to the optical fibers, comparing the sum of signal outputs from regions of the image sensor, which regions correspond respectively to the laser beams, with a signal output corresponding to a standard beam intensity required for the exposure of a photosensitive material to determine a value to be corrected, and then feeding the value back to acousto-optic light modulators so as to change the modulation efficienties of the acousto-optic light modulators.

Method for correcting beam intensity upon scanning and recording a

In a picture scanning and recording system such as a color scanner wherein a reproduction picture is recorded by modulating a plurality of light beams each independently according to a picture signal by means of light modulator elements, a method and apparatus for recording a reproduction picture having a substantially continuous tone characterized by weighting each light beam in order of digit position of a digitized picture signal, and effecting exposure with a light beam resulting from optical addition of the light beams modulated according to such a digital picture signal.

Method and apparatus for recording a reproduction picture having a

A method for setting up density values of highlight and shadow points of original pictures to a picture reproducing machine such as a color scanner and a color facsimile, wherein one of the original pictures now being scanned is discriminated to output a discrimination signal, and wherein the highlight and the shadow point density values or values corresponding to a density range of the one original picture are read out of a memory in which the highlight and the shadow point density values or the values corresponding to the density ranges of the original pictures are stored, by addressing the memory by means of the discrimination signal, and then are set up to the picture reproducing machine.

Growing community of inventors

Kyoto, Japan

Takeshi Yoshimoto