JPH1052929A - Laser absorbent image drum for scanner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image processor using an image drum which has a laser-absorbing substance substantially eliminating undesirable reflected laser beams which would cause an artifact to write elements during a write operation. SOLUTION: The image processor receives a medium for processing of images and comprises a print head for supplying and directing laser beams. An image receiver arranged adjacent to the print head receives the medium exposed to laser beams projected outside the print head and partly penetrating the medium to reach an image drum 110. A laser-absorbing coating 330 is coated on the image drum so as to absorb laser beams received by the image receiver to substantially eliminate an undesired artifact.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lathe bed scanner using a rotating image drum to maintain the positional relationship between a donor element and a writing element during a writing process.
More particularly, it relates to an imaging drum having a laser absorber that substantially eliminates unwanted reflected laser beams that cause artifacts in the writing element during writing.

[0002]

BACKGROUND OF THE INVENTION Color proofing (proofing) is a method of printing a printed image without the time and cost required to actually set up a high-speed, high-volume print press that prints a sample of the intended image. This process is used in the printing industry to form a representative image to be copied. One such color proof press is a lathe bed scanner, which uses a halftone capable thermal printer. The printer is arranged to form an image on a thermal print medium or writing element, wherein the donor transfers the dye with a sufficient amount of thermal energy. The printer includes a plurality of diode lasers, each of which is modulated by an information signal to supply energy to a selected area of the media.

The printhead includes one end of a fiber optic array having a plurality of optical fibers coupled to a diode laser that carries the signal from the laser to the printhead. The writing element is supported on a rotatable imaging drum, and the printhead having a fiber optic array is movable with respect to the longitudinal axis of the drum. Dye is transferred to the writing element as radiation carried by the optical fiber from the diode laser to the donor element is converted to thermal energy at the donor element.

[0004] The cylindrical imaging drum includes a hollowed interior portion and furthermore its housing allowing a vacuum from the interior of the drum to the receiver and the writing element to maintain its position as the drum rotates. Includes a plurality of holes extending through the body. During the writing process, the printhead emits a laser beam as it moves along the drum. The beam then passes through the donor element so that the dye is transferred to the writing element. A portion or the remainder of the laser beam remains due to incomplete thermal transfer, which is then conveyed through the writing element onto the imaging drum.

[0005] Although the scanners known and used at present are satisfactory, they are not without their drawbacks. The remaining beam is reflected off the imaging drum and then reflected back through the writing element,
It creates undesirable artifacts in the writing element. Accordingly, there is a need for an improved lathe bed configuration that overcomes the above disadvantages.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems.

[0007]

SUMMARY OF THE INVENTION In summary, according to one aspect of the present invention, the present invention provides an image processor for receiving a medium for processing. The processor comprises a printhead that supplies and directs a laser beam. An image receiver positioned adjacent to the printhead exits the printhead and a portion of the beam receives the medium exposed to the laser beam passing through the medium and reaching the image drum. A laser absorbing coating is coated on the image drum to absorb the laser beam received by the image receiver to substantially remove unwanted artifacts.

It is an object of the present invention to coat the drum with a laser absorbing coating to overcome the above disadvantages. An advantage of the present invention is that it provides a cost effective device for implementing the present invention. It is a feature of the present invention to provide a laser absorbing coating that is coated on an imaging drum to absorb the laser beam received by the imaging drum to substantially eliminate unwanted artifacts.

[0009]

BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects of the invention will become more apparent with reference to the following description and drawings where like reference numerals are used to identify like elements that are common to the figures. Becomes Referring to FIG. 1, a lathe bed scanner 10 of the present invention having a housing 15 forming a protective cover is shown. A movable hinged door 20 allows access to two media trays, a lower tray 30a and an upper tray 30b, which are located inside a housing 15 which supplies receiver material 40, typically paper. It is attached to the front part of the housing 15. Only one media tray 30 feeds receiver material 40 out of that paper tray 30 to form an image thereon, and alternative media tray 30 holds different types of paper or acts as a backup That will be apparent to those skilled in the art. In this regard, the lower media tray 30a is a lower media roller 60a capable of rotating the paper 40.
And finally includes a cam 50a that lifts upwards toward a second rotatable upper media roller 60b, which allows the receiver material 40 to be pulled upwards toward the media guide 70 as both rotate. I do. Upper media tray 30b also includes a cam 50b that lifts toward upper media rollers 60b that direct receiver material 40 toward media guide 70.

The movable media guide 70, as indicated by the apparent position, includes a receiver under a pair of rollers 80 that engages the receiver material 40 to assist the upper media rollers 60b to direct the upper media rollers 60b onto the staging tray 90. Go to material 40. The media guide 70 is mounted at one end inside the housing 15 and moves in a hinged manner so that the other end can be placed in many positions of the media guide 70. The media guide 70 then rotates down its unobstructed end, as shown by the solid line, and the direction of rotation of the upper media roller 60b is directed to the rear staging tray 90 below the roller 80.
An overlying receiver material 40 is sent upward through the inlet passage 100 and is reversed to be sent around a rotatable imaging drum 110.

[0011] Four rolls of donor material 120 (only one is shown) are connected to carousel 130 at a lower position of housing 15, each roll being typically black, yellow, magenta, cyan. Color donor material 120
including. These donor materials are ultimately cut into sheets and passed to an imaging drum that forms the media, and the dye embedded therein is passed to a receiver material placed thereon, the processing of which is described in detail below. Will be described. In this regard, the drive mechanism 140 is attached to each roll 120 and includes three rollers 150 through which the donor material 120 in question is wound up in the knife assembly 160. After the donor material 120 reaches a predetermined position, the rollers 150 stop driving the donor material 120, and the two blades 170 located at the bottom of the knife assembly cut the donor material 120 into a sheet. Medium roller 60a,
60b and media guide 70 transfer donor material 120 to drum 11
0 and aligns with receiver material 40 using the same process described above for sending receiver material 40 onto drum 110.
Donor material 120 is placed over receiver material 40 having a narrow gap between the two formed by the microbeads embedded in receiver material 40.

The laser assembly 180 includes 20 lasers 185 therein, which are connected to the coupling head 190 and ultimately the write head 200 via fiber optic cables 187. The write head 200 produces thermal energy from the signal received from the laser 185 to apply the dye of the donor material 120 to the receiving material 40.
Try to send across the gap to. Write head 200 is attached to lead screw 210 via a nut (not shown in FIG. 1) that allows it to move axially along the longitudinal axis of drum 110, which writes data onto receiver material 40.

For writing, the drum 110 rotates at a constant speed, and the writing head 200
Starting at one end, the entire length of the receiver material 40 is followed to complete the transfer process for a particular donor material placed on the receiver material 40. After the donor material 120 has completed its dye transfer, the donor material 120 is transported from the drum 110 and skived or ejected by a chute 21.
0 and is taken out of the housing 15. The donor material eventually becomes allowed to be placed on the donor material tray 212 for removal by the user. The above process is repeated for the other three rolls of donor material.

After all four sheets of the donor material have transferred their dye, the receiver material 40 is transported via the transport mechanism 220 through the entrance door 230 to the dye coupling assembly 240, where it is connected to the exit door 250 Is placed towards. The entrance door 230 is opened to allow the receiver material 40 to enter the dye-binding assembly 240 and closed once it has been placed in the dye-binding assembly 240. Dye binding assembly 240 heats receiver material 40 such that the transferred dye is further bound onto receiver material 40 and seals the microbeads thereon. After heating, the exit door 250 is opened, and the receiver material 40 having the image thereon is sent out of the housing 15 and placed against the stop 260.

Referring to FIG. 2, a perspective view of the image drum 110 and the write head 200 of the lathe bed scanner 10 is shown. The image drum 110 is provided to rotate about an axis (x) on a frame support 270. The write head 200 is movable with respect to the imaging drum 110 and is arranged to direct a beam of photochemically directed light onto the donor material 120 (see FIG. 1). Write head 20
0 includes a plurality of writing elements (not shown) therein;
It can each be modulated by an electronic signal from a laser diode 185, the signal representing the shape and color of the original image, so that each dye has its presence reconstructed into the original target color. It is heated to sublime only in the required area on the receiver material 40.

The writing head 200 includes a movable moving member 2.
80, which are supported for low friction sliding movement on bars 290,300. Bars 290, 300
Have no deflection or distortion between the mounting points at their ends and are positioned as parallel as possible with respect to the axis (x) of the image drum 110. The upper bar 300 is provided to be accurately positioned on the axis (x) of the drum 110 such that the write head 200 has the axis of the write head perpendicular to the axis (x) of the drum. The upper bar 300 positions the moving member 280 vertically and horizontally with respect to the axis of the drum 110. Lower bar 29
0 places the moving member 280 only with respect to the rotation of the moving body with respect to the bar 290, thereby over-constraining the moving member 280 causing binding, chatter, or transmission of unwanted vibrations to the write head 200 during image formation. There is no.

Referring to FIG. 3, there is shown an image drum 110 having a cylindrical housing 305 partially sealed at both ends by two plates 310, respectively. The housing 305 further includes a hollow interior (annular in vertical cross-section) so that a vacuum can be evacuated from its interior. The plurality of holes 320 are provided in the drum 110
Has spread through the housing 305 so that the vacuum can hold the donor 120 and the writing element 40 thereon during the rotation of.

A diamond-like carbon (DLC) coating 330, commercially available from Diamondnex, is applied to housing 305 by well known RF (radio frequency) sputtering techniques. Coating 330 absorbs the remaining laser beam that is not absorbed by the writing element, which otherwise reflects off the drum surface without being absorbed. This absorption substantially eliminates the unwanted laser beam, which typically generates artifacts on the writing element during the writing process. The coating 330 is preferably coated at a thickness of between 5,000 and 50,000 angstroms and includes a chemical structure having similar, but not identical material properties to diamond.
This type of coating 330 has an infrared range of 600
Absorbs electromagnetic radiation in the range from to 900 nanometers;
Scanners typically write in the 800 to 900 nanometer range.

The coating 330 can also be made by ion beam deposition or other well-known techniques such as plasma assisted chemical vapor deposition. However, RF sputtering is preferred because it requires lower application temperatures and provides a strong bond to the surface of drum 110. The invention has been described with reference to the preferred embodiments. However, modifications and improvements can be made by those skilled in the art without departing from the scope of the invention.

[Brief description of the drawings]

FIG. 1 is a diagram showing a vertical section of a lathe bed scanner of the present invention.

FIG. 2 is a perspective view of an image drum, a laser writer, and a lead screw of the present invention.

FIG. 3 is a perspective view of the image drum of the present invention.

[Explanation of symbols]

 Reference Signs List 10 scanner 15 housing 20 door 30, 30a, 30b, 90 tray 40 receiver material 50, 50a, 50b cam 60, 60a, 60b, 80 roller 100 entrance passage 110 image drum 120, 150 roller 130 circular conveyor 140 drive mechanism 160 knife Assembly 170 Blade 180 Laser Assembly 185 Laser 190 Coupling Head 200 Write Head 210 Eject Chute 212 Donor Material Tray 220 Transport Mechanism 230 Inlet Door 240 Dye Coupling Assembly 250 Outlet Door 260 Stopper 270 Frame Support 280 Moving Member 290, 300 Bar 305 Housing 310 End plate 320 Hole 330 Coating

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Svetlana Resnick, New York, USA 14625, Rochester, Bunker Hill Drive 59 (72) Inventor Shamal Kay Gosh United States, New York 14612, Rochester, Craiton Lane 42

Claims (3)

[Claims] 1. A printhead for supplying and directing a laser beam; and (b) a medium exiting from the printhead and a portion of the beam being exposed to the laser beam passing through the medium and reaching an imaging drum. (C) a laser absorbing coating coated on the image drum that absorbs a portion of the laser beam received by the image receiver to substantially remove unwanted artifacts; An image processor that receives a processing medium. 2. A body that holds the medium exposed to the laser beam where a portion of the beam passes through the medium and arrives on a substantially cylindrical body; and (b) substantially eliminates undesired artifacts. An image drum holding a medium suitable for writing thereon, comprising a laser absorbing coating coated on the body for absorbing a laser beam received by the image receptor for removal. 3. A platform for holding the medium exposed to a laser beam where a portion of the beam passes through the medium and reaches the platform; and (b) to substantially eliminate unwanted artifacts. An image receptor holding a medium suitable for writing thereon comprising a laser absorbing coating coated on the platform for absorbing a laser beam received by the image receptor.