Method of recording signals on bands by means of laser beams and

Recorders – Printing – dotting – or punching marker – Ink transfer support or moving means

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

354 5, G01D 942

Patent

active

044196768

DESCRIPTION:

BRIEF SUMMARY
FIELD OF THE INVENTION

The invention relates to a method for recording signals on bands so that signal information transmitted in digital form from a source can be recorded in a suitable recording surface in each band comprises a plurality of character raster lines. The main field of application of the invention includes electronically controlled character printers, text writing copiers and electronic film producing techniques. The invention relates also to an apparatus for carrying out the method.


BACKGROUND OF THE INVENTION

In the DE OS No. 2 755 575 a laser-operated signal recording apparatus is described that comprises an acousto-optical cell utilizing Bragg diffraction for generating a plurality of simultaneously outgoing diffracted laser beams. The outgoing laser beams are projected on a signal recording surface by means of a suitable optical system and the beams are also deflected to scan a band-like raster on the signal recording surface. The acousto-optical cell is controlled in accordance with the information defined by the shape of the characters to be recorded, and the scanning beams illuminate the recording surface in locations that correspond to the presence of the characters. The areas that do not comprise characters are not illuminated at all.
This known apparatus provides for rapid information recording, and because of to the application of a multi-beam raster the speed of its electronic circuitry does not have to be above normal values.
There are a large number of conventional multi-beam information recording devices including the above cited system that have a common drawback, namely, that the recording surface is illuminated at locations corresponding to the positions of the characters to be recorded. Usually in the recorded documents the character locations should have a definite shade that distinguishes them from the generally white shade of the carrier (paper). For ensuring such properties in conventional laser operated recording equipment of the above type, an electrophotographic image reversal is used, by means of which the recorded document comprises positive (black) surfaces at the illuminated locations.
The moodes used for electrophotographic image reversal are substantially complex and expensive compared to the widely used document copying equipments intended for use in offices. In such equipments positive copies are produced without electrophotographic image reversal, and the copy is black at locations in which the original document is black.
In order to eliminate the latter type of image reversal in laser operated recording equipment the image reversal may be carried out by optoelectronic means by the appropriate control of the laser beam used for recording the characters.
In the periodical "Electronics" (No. 5 1979, pp 46 to 48) an apparatus is described, in which a single laser beam scans a raster on the recording surface, and the control of the laser beam occurs in accordance with optoelectronic image reversal. This way in that apparatus there is no need for electrophotographic image reversal, and positive copier units can be used for the image recording.
The application of a single laser beam that scans each raster line of the character separately necessitates a remarkable increase in the scanning frequency compared to multi-beam recording technique, if the time of the recording remains unchanged. The required fast deflection of the laser beam cannot be effected by means of the widely used swinging mirror technique. Such fast scanning can be realized by an expensive rotating mirror or by means of an additional acousto-optical cell. Due to the higher speed used in the single beam technique, the speed of controlling the acousto-optical cell must also be increased in a corresponding manner. This means that high speed electronic circuits must be used, which substantially contributes to the production costs. To ensure an undistorted image reconstruction from the raster image a precise synchronism should be provided between the movement of the scanning beam and the displace

REFERENCES:
patent: 3713721 (1973-01-01), Watson
patent: 4019186 (1977-04-01), Dressen et al.
patent: 4253102 (1981-02-01), Kataoha et al.
Watson, Hugh A., Bell Laboratories Record "An Experimental Page Facsimile System", Mar., 1975, pp. 163-167.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Method of recording signals on bands by means of laser beams and does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method of recording signals on bands by means of laser beams and, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of recording signals on bands by means of laser beams and will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-2032224

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.