JPH11228000A - Centering method for photographic printing paper and optical digital printer employing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a centering technique for setting photographic printing paper to a correct position at an exposure region and an optical digital printer employing the centering technique. SOLUTION: Movable width-controlling guides 101, 102 for guiding both the sides, right and left, of photographic printing paper passing through an exposure part 40 for irradiating the photographic printing paper RP pressed and fed by feeding mechanisms 44, 46 with light based on picture image data are allowed to set at a guide position for evolving guide width wider than the width of the photographic printing paper, and a centering position for evolving guide width narrower than the width of the photographic printing paper. Centering for the photographic printing paper is carried out by moving the right and the left width-controlling guide to the centering position from the guide position with the pressing of the photographic printing paper releasing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for irradiating a photographic paper, which is pressure-conveyed by a conveying mechanism while being guided by a movable width-regulating guide arranged on both right and left sides, with light based on image data to form an image on the photographic paper. The present invention relates to a method for centering photographic paper in an optical printer for printing images, and an optical digital printer employing the centering method.

[0002]

2. Description of the Related Art In an optical printer of a liquid crystal shutter system or a CRT system, a photosensitive material (generally photographic paper, hereinafter referred to as photographic paper or paper) is accurately arranged with respect to a light beam irradiation surface at the time of exposure. Need to be in close contact. In particular, in the type of performing line exposure, an image is printed in a predetermined area by sequentially performing line exposure while transporting the photographic paper, so that the photographic paper transport accuracy is required. For this reason, the photographic paper transport line is provided with width regulating guides arranged on both left and right sides.

[0003]

However, since the width of photographic paper has an error determined by the JIS standard, the guide width created by the width regulating guide is set to a value obtained by adding up the error. Therefore, when ordinary photographic paper is used, a gap of about 1 mm at the worst may occur between the side edge of the photographic paper and the guide surface. The existence of such a gap causes the printing paper to be inclined with respect to the light beam irradiation surface. When the photographic paper is exposed in such a state, the image printed on the photographic paper is inclined with respect to the photographic paper, and becomes unsightly when finished as a photographic print. In particular, since this inclination changes every time an image is printed, the difference becomes large and noticeable when a plurality of photographic prints are viewed side by side. SUMMARY OF THE INVENTION An object of the present invention is to provide a centering technique for setting a photographic paper in an accurate posture in an exposure area and an optical digital printer employing the centering technique.

[0004]

In order to achieve the above object, light based on image data is applied to photographic paper conveyed by pressure by a conveying mechanism while being guided by movable width regulating guides arranged on both right and left sides. In the centering method of photographic paper in an optical printer for printing an image on photographic paper, in the present invention, a first step of setting a guide width created by the left and right width regulating guides to a predetermined value wider than the width of the photographic paper; A second step of transporting the photographic paper to the printing area while being guided by the width regulating guide set to the predetermined value, a third step of releasing the pressure bonding of the transport mechanism for transport, and the left and right width regulation. A fourth step of setting the guide width of the guide to a predetermined value equal to or less than the width of the photographic paper, a fifth step of re-pressing the transport mechanism, and the left and right width regulating guides. Characterized in the sixth step of the guide width is set to wider predetermined value than the width of the paper, in that it consists of.

In this method, the holding of the printing paper by the transport mechanism is once released, the printing paper is released, the width of the width regulating guide is reduced to the width of the printing paper or less, and the printing paper is forcibly centered on the center of the transport line. Match. Thereafter, the photographic paper is again held by the transport mechanism, and the width regulating guide is expanded to a predetermined guide width larger than the nominal width in consideration of an error in the photographic paper width. In this manner, by performing the alignment of the printing paper every time the image is printed, it is possible to obtain a print in which the image is printed in a correct posture.

In a preferred embodiment of the present invention, the pair of left and right movable width regulating guides are disposed upstream and downstream in the photographic paper transport direction with the irradiation point interposed therebetween. There is a method in which the regulation guide moves synchronously. In this case, since the centering is performed on both sides of the irradiation point where the image is printed on the photographic paper in the photographic paper conveyance direction, the posture of the photographic paper with respect to the irradiation point can be adjusted optimally.

Further, as one of preferred embodiments of the present invention, the third to sixth steps are performed after a conveying step of feeding an area to be exposed on the photographic paper beyond an irradiation point, and thereafter, the third step is performed. There is a method in which image printing is performed by irradiating light to an area to be exposed on the photographic paper in a conveyance step of pulling back the photographic paper. In this method, the image is printed on the photographic paper when the centered photographic paper is returned and transported while being pressed by the transport mechanism, so that the printing process can be performed in a precise posture up to the leading edge of the photographic paper without waste. Become.

A transport mechanism for pressing and transporting the photographic paper;
An exposure unit that prints an image on photographic paper by irradiating light based on image data to the photographic paper conveyed by pressure by the transport mechanism, and a movable width regulating guide that guides both left and right sides of the photographic paper passing through the exposure unit In the present invention, the left and right width regulating guides can be set to a guide position for creating a guide width wider than the width of the photographic paper and a centering position for creating a guide width smaller than the width of the photographic paper. With the configuration in which the left and right width regulating guides are shifted from the guide position to the centering position in a state where the photographic paper by the transport mechanism is released from the pressure contact, the centering of the printing paper is performed. With this operation, it is possible to obtain a print on which an image is printed in a correct posture.

Further, when the exposure section is constituted by a line exposure type such as a line type fiber optical CRT, the pair of left and right movable width regulating guides are arranged on the upstream and downstream sides of the exposure section with respect to the photographic paper transport direction. Then, by moving both movable width regulating guides by a common drive source,
It is possible to satisfy the requirement of an accurate posture of the photographic paper with respect to the line exposure area. Other features and advantages according to the present invention will become apparent from the following description of embodiments with reference to the drawings.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a digital printer employing a photographic paper centering method according to the present invention will be described as an example of a digital printer incorporated in a photographic processing apparatus.

(Overall Configuration of Photosensitive Material Processing Apparatus) The photographic processing apparatus shown in FIGS. 1 and 2 has a digital print section 1 as a digital printer for exposing an image based on digital data to roll paper RP. Cut paper transport unit 105 for transporting the photographic paper after cutting it into cut paper SP, and exposed cut paper S
The developing unit 300 includes a developing unit 300 that receives P in a plurality of tanks and performs a developing process with a developing solution, and a finishing unit 400 that dries the cut paper SP after the developing process and arranges the cut paper SP on a tray as a finished print. In this specification, photographic paper is used as a general term for photographic light-sensitive materials, and long photographic paper is called roll paper, and photographic paper cut for printing is called cut paper.

When viewed from the front of the photosensitive material processing apparatus, the digital exposure section 1
The control unit 200 for controlling the operation of, the transmitted light printing unit 150 for exposing an image obtained as transmitted light from a negative film or the like to the roll paper RP is disposed, and on the cut paper transport unit 105 A paper magazine PM1 for the digital printing unit 1 is detachably provided below the digital printing unit 1, and a paper magazine PM2 for the transmitted light printing unit 150 is provided below the digital printing unit 1.

The digital printing section 1 has digital image data obtained by reading an image of a film provided to the transmitted light printing section 150 with an image pickup device such as a CCD, or
A fiber optical type CRT engine 2, which is a type of optical printer that performs line exposure of the roll paper RP, based on digital image data directly provided by a customer through a data storage medium such as a floppy disk, MO or personal computer communication, is installed. ing. The principles of this type of CRT printer are well known and are described, for example, in U.S. Pat. No. 4,309,720.

(Schematic Configuration of Entire Digital Printing Unit) As shown in FIG. 3, the digital printing unit 1 draws a roll paper RP from a paper magazine PM1 and sends it to the digital printing unit 1; Exposure operation unit 40 located near the center of unit 1 and paper transport direction switching unit 70
including. The paper loading section 20 near the upper end has, in addition to the first feed roller 22, a first path switching guide 24 for forming a photographic paper loop in a first loop box RB1 formed above the CRT engine 2. .

The paper transport direction switching unit 70 provided downstream of the exposure operation unit 40 includes a paper transport direction switching unit
In addition to the second feed roller 72 that can be supplied to the side, a second path switching guide 74 for forming a retraction loop as necessary in a second loop box RB2 arranged at the same level as the cutter unit 80 is provided. . In the exposure operation unit 40, a tube surface 42 formed at the tip of the CRT engine 2
Is projected onto the photographic paper transport line, and the light beam excited by the electron beam emitted from the electron gun in the CRT engine 2 exits from the tube surface 42 and is conveyed by being pressed against the tube surface 42 and conveyed. The emulsion surface of RP is irradiated and the image is printed. The tube surface 42 functions as an exposure unit for photographic paper.

Further, the exposure operation section 40 further includes an exposure operation roller 44 and a pressure roller 46 which can press and hold the roll paper RP against the exposure operation roller 44. The roll paper RP once conveyed to the cutter unit 80 side or the second loop box RB2 side is synchronized with the movement of the exposure operation roller 44 while the front surface of the tube surface 42 is pulled up at an accurate speed by the exposure operation roller 44. The exposure is performed by the driven CRT engine 2. In addition, immediately before and after the exposure operation unit 40, the CRT
A paper centering mechanism 100 for centering the roll paper RP in the width direction with respect to the pipe surface 42 of the engine 2 is provided.

The digital print section 1 is housed in a light-shielding box 3 for holding the roll paper RP drawn out of the paper magazine PM1 for exposure processing in a dark room state. It has a drawer mechanism for easily pulling out the print unit 1 from the light-shielding box 3 and performing inspection and maintenance in a light room. Further, the cut paper transport unit 105 disposed adjacent to the downstream of the digital print unit 1 is provided with a cut paper S cut as a print.
P is transported in a state of being sandwiched between two transport belts arranged opposite to each other.

(Structure of Paper Loading Unit) As shown in FIG. 4, the paper loading unit 20 mainly includes
It comprises a first feed roller 22 and a first path switching guide 24. The first feed roller 22 is a paper magazine PM1.
The rotation is driven by a motor (not shown) around an axis parallel to the axis of the roll paper RP. The first path switching guide 24 has an axis X parallel to the first feed roller 22.
A swing arm 25 that can swing up and down around one turn is provided with a first pressure roller 26 near the upper end thereof.
However, a loop roller 28a and an auxiliary loop roller 28b are both rotatably supported near the lower end.

The swing arm 25 has a linearly extending loading guide surface 25a and, at the same time, a loading posture in which the loading guide surface 25a assumes a substantially vertical posture by an actuator such as a rotary solenoid. While the swinging operation of the swing arm 25 is performed while the swinging arm 25a swings between the loop postures which are flipped up, the swinging arm 25 has an elastic restoring force lower than the operating force of the actuator. , And the other end is fixed to the swing arm 25). When the swing arm 25 is in the loading position, the loading guide surface 25a forms a vertically extending paper loading path with the fixed guide surface 30, and at the same time, the first pressure roller 26 The roller is pressed in the direction of the peripheral surface of the feed roller 22, and the tangent between the two rollers is substantially perpendicular (along the loading guide surface 25a). Therefore, when the first feed roller 22 is rotated forward in this state, the roll paper RP is pulled out of the paper magazine PM1 by being sandwiched between the first feed roller 22 and the first pressure roller 26. It is guided along the paper loading path formed by the loading guide surface 25a, and is loaded on the exposure operation unit 40 side.

On the other hand, when the swing arm 25 is in the loop position, the loading guide surface 25a and the first feed roller 22 are flipped up to open the wide opening of the first loop box RB1. Further, since the first pressure roller 26 is also separated from the first feed roller 22, the roll paper RP is kept pressed against the first feed roller 22 by the remaining pressing rollers 27.
27 to the first loop box RB1 side,
Further, (in the loading position, the roll paper R
The first loop box RB is moved so that the loop roller 28a (which has been retracted to the paper magazine PM1 side so as not to interfere with P) enters the paper loading path.
Come in within 1. Therefore, after a part of the roll paper RP loaded vertically to the exposure operation unit 40 side by the above-described process is held by the exposure operation roller 44 and the pressure roller 46, the first feed roller 22 is moved in the loop posture. When turned forward again, the paper magazine P
Roll paper RP newly supplied from M1 is the first roll paper.
It is guided in the loop box RB1 and stored in the box as a basic loop in the form of a loop.

After the basic loop is once formed in this manner, the swing arm 25 is maintained in the loop posture, the first feed roller 22 is stopped, and the exposure operation roller 4 is stopped.
When roll 4 is reversed, roll paper R returned
P is guided into the first loop box RB1 by the auxiliary loop roller 28b of the swing arm 25 to form a loop in the box. Due to the existence of such a basic loop, the roll paper RP required for the exposure, which is necessary as a preparation stage for the exposure operation, is sent in advance in the transport direction downstream (developing unit side) of the exposure operation unit 40 in advance. At this time, it is pulled out of the loop without being pulled out from the paper magazine PM1. The return of the roll paper RP during exposure is
It is absorbed in this loop.

Incidentally, the loop roller 28a and the auxiliary loop roller 28b are further provided with an axis X with respect to the swing arm 25 itself.
Arm member 2 supported so as to be able to swing back and forth in one direction
9, a coil spring 26a for urging the arm member 29 toward the first loop box RB1 is provided between the swing arm 25 and the arm member 29. Therefore, in order to make the loop roller 28a enter the first loop box RB1, the swing arm 2
Even when the loop 5 is in the loop position, the loop roller 28a is not moved (due to paper jamming or the like).
If a large stress is applied from the first loop box RB1 side, the loop roller 28a together with the arm member 26 can be retracted closer to the paper magazine PM1 than the fixed guide surface 30. However, when the swing arm 25 is in the loading posture, the swing arm 25 is provided with an arm so that the loop roller 28a maintains the posture retracted from the paper loading path regardless of the biasing force of the coil spring 26a. A stopper 25c for stopping the swing of the member 29 at a predetermined angle is formed.

Further, the swing arm 25 includes the coil spring 2
If the roll paper RP is jammed in the loading path while the first path switching guide 24 is in the loading state, the swing arm 2
5 can be swung toward the loop posture side against the urging force of the coil spring 25b. In the paper loading section 20, the first pressure roller 26 and the first feed roller 22 are main components of the photographic paper transport mechanism.

(Structure of Exposure Operation Unit) As shown in FIGS. 5, 6, 7, and 8, the exposure operation unit 40 includes a CRT engine 2
In addition to the tube surface 42, an exposure operation roller 44 made of metal (aluminum or the like) driven by a step motor M1, a pressure roller 46 formed by covering the peripheral surface of a core metal with a synthetic rubber layer such as NBR, It includes a paper bypass mechanism 48 for keeping the roll paper RP apart from the tube surface 42 except during operation, and a pressing pad 50a for pressing the roll paper RP against the tube surface 42 during an exposure operation.

The pressing roller 46 is pressed against the exposure operation roller 44 to hold the roll paper RP, and the pressing roller 46 is separated from the exposure operation roller 44 and
P can be displaced between the release positions for releasing P, and the pressing pad 50a is similarly moved from the roll paper RP to the tube surface 42.
It can be switched between the crimping position and the releasing position. The postures of the pressure roller 46 and the pressing pad 50 a are collectively operated by a first posture control cam mechanism 52 provided in the exposure operation unit 40.

The first attitude control cam mechanism 52 has a box-shaped main body 52a supporting the exposure operation roller 44 at both ends, and a pair of rotatably supported both ends of the pressure roller 46 on the main body 52a. The first swinging small piece 60, a pair of swinging plates 54a, 54a 'swingable around an axis X2 located near the lower end of the main body 52a, and a position extending in a crank shape from the rotation axis of the DC motor M2. It has a bearing 55 rotatably provided. The first swinging piece 60 is attached to the main body 52.
The swinging plates 54a, 54a 'and the first swinging small pieces 60 are individually linked to each other via a link mechanism 53 in such a manner that the swinging plates 54a, 54a' and the first swinging pieces 60 are swingably supported around an axis X3 provided on the shaft a. I have. The pair of rocking plates 54a, 54a 'are fixed by a common horizontal rod 56 rotatable on the axis X2, and the bearing 55 has a long hole formed on one side of the rocking plate 54a. 54b is slidable.
The elongated hole 54b extends upward from the arc-shaped cam portion 54c and the arc-shaped cam portion 54c having the same curvature as the outermost circle drawn by the revolving bearing 55, and has a width substantially equal to the outer diameter of the bearing 55 itself. The first linear cam portion 54d has a second linear cam portion 54e extending from the arc-shaped cam portion 54c in a direction opposite to the first linear cam portion 54d.

The link mechanism 53 is provided with the first swinging small piece 6.
0, an axis X4 located between the axis X2 and the axis X3.
A second swinging piece 62 that can swing around and a first swinging piece 6
0 and one end 62a of the second swinging small piece 62. By the swinging of the pair of first swinging pieces 60, the pressing position and the releasing position of the pressure roller 46 are alternatively created, but are individually connected to the pair of first swinging pieces 60. The pressure roller 46 is always urged to the pressure position by the left and right coil springs 60c and 60d. In addition, pressing pad 5
0a is also urged by a torsion spring to a release position separated from the tube surface 42 while being supported by a swing member 50b capable of swinging about the axis X2 separately from the first swing small piece 60 and the swing plate 54a. On the other hand, an engagement pin 50c extending from the left and right ends of the swing member 50b to above the pressing pad 50a is provided.
The engaged portion 5 provided on the pair of rocking plates 54a, 54a '
4p.

Then, when the DC motor M2 is rotated forward,
In accordance with the orbital movement of the bearing 55, the first attitude control cam mechanism 52 sequentially shows the following states. FIG. 9 (a) which occurs when the bearing 55 is at the point A of the orbit.
In the first state shown in FIG.
4b, it is located near the entrance of the second linear cam portion 54e, and as a result, the swinging plate 54a maintains a substantially vertical posture. In this first state, no acting force acts on the link mechanism 53 and the first swinging small piece 53a from the swinging plate 54a, so that the pressure roller 46 has the coil springs 60c and 60d.
Is pressed against the exposure operation roller 44,
The pressing pad 50a is configured such that the engagement pin 50c is
Since it is released from the state of engagement with a, it is separated from the tube surface 42 by the urging force of the torsion spring.

FIG. 9 (b) which occurs when the bearing 55 is slightly forward (counterclockwise) from point A and is at point B on the orbit.
In the second state shown in FIG.
4b, enters the arc-shaped cam portion 54c, and as a result,
The oscillating plate 54a maintains a posture that is greatly inclined toward the tube surface 42 side. In this second state, the rocking plate 54a is still
Since there is no acting force on the link mechanism 53 and the first swinging piece 60 from the above, the pressing roller 46 keeps the above-mentioned pressing position, while the engaging pin 50c of the pressing pad 50a It is pressed against the tube surface 42 by engaging with the engaged portion 54p. The exposure operation performed by pressing the roll paper RP against the tube surface 42 is performed in the second state.

In the third state shown in FIG. 10A, which occurs when the bearing 55 further rotates forward from the point B and is at the point C on the orbit, the bearing 55 is in the first straight line within the elongated hole 54b. Penetrates into the cam portion 54d, and as a result, the swing plate 5
4a maintains a posture slightly inclined to the tube surface 42 side. In the third state, the situation is substantially the same as in the first state. That is, the pressing roller 46 is still in the pressing position, but for the pressing pad 50a, the engaging pin 50c is kept engaged with the engaged portion 54p and the tube surface 42 is still in contact.
The pressing pad 50a is restored to a state of being separated from the tube surface 42.

In the fourth state shown in FIG. 10 (b), which occurs when the bearing 55 is slightly rotated forward from the point C and is at the point D on the orbit, the bearing 55 has an arcuate cam within the elongated hole 54b. Part 54c, and as a result, the swing plate 54a
Maintain a posture slightly inclined to the opposite side to the tube surface 42. In the fourth state, the pressing pad 50a maintains the state of being separated from the tube surface 42 as before, but the pressure roller 46 assumes the position separated from the exposure operation roller 44. That is, in the fourth state, the side surface of the swinging plate 54a acts on the action point 62b formed on the second swinging small piece 62 to tilt the second swinging small piece 62 downward around the axis X2. Since the one end 62a of the second swinging small piece 62 is displaced downward by the tilting of the second swinging small piece 62, the link arm 64 to which the lower end of the second swinging small piece 62 is connected with the lower end of the second swinging small piece 62 also slightly. Displaces downward while tilting. Due to the downward displacement of the link arm 64, the one end 60a of the first swinging small piece 60 is displaced downward around the axis X3.
Takes a posture separated from the exposure operation roller 44 against the urging force of the coil springs 52c and 52d. Note that the sensor PS3 can detect that the pressing roller 46 is in the pressing position with respect to the exposure operation roller 44, and that the releasing of the pressing roller 46 from the pressing position is detected by the sensor P3.
The detection is enabled by S1. Preparation for Exposure Operation The operation of first loading the roll paper RP into the exposure operation unit 40 is possible in this fourth state. In addition, since the arc-shaped cam portion 54c with which the bearing 55 contacts in the second state and the fourth state has the same curvature as the outermost circle drawn by the revolving bearing 55 as described above,
Even if the DC motor M2 and the bearing 55 stop at a position slightly overrun from the predetermined position,
There is no effect on the posture of 4a.

As shown in FIGS. 11A and 11B, immediately below the pressure roller 46 and the exposure operation roller 44, a roll paper RP as a paper bypass mechanism is placed on the tube surface 4.
A pair of guide members 65 and 66 for guiding the front surface of the second member 2 are provided. One of them is a fixed guide 65 that does not move, while the other is a movable guide 66 that can swing around an axis 66a. The movable guide 66 has its lower end 66b retreated toward the CRT engine 2 body side from the tube surface 42, and
In cooperation with the fixed guide 65, the roll paper RP
Exposure posture for guiding a route that can contact with the lower end portion 66 and the lower end portion 66
b protrudes forward from the tube surface 42 and roll paper R
It is possible to swing between the detour postures in which P is detoured so that it cannot contact the pipe surface 42. That is, in the detour posture, the roll paper RP is transferred from the gap between the pressure roller 46 and the exposure operation roller 44 to the paper transport direction switching unit 70 downstream of the exposure operation unit 40, and further downstream to the cutter unit 80 side. (In a state where there is no fear of damage due to contact with the tube surface 42).

The movable guide 66 is normally held in the detour position by a torsion spring 66c, and is switched to the exposure position when an exposure operation is required. That is, in the exposure operation, first, the first attitude control cam mechanism 52 is switched from the fourth state to the first state, so that the pressure roller 4
6 presses the roll paper RP against the exposure operation roller 44, and subsequently, when the first attitude control cam mechanism 52 switches to the second state, the swinging member 50b tilts toward the tube surface 42 side, and the pressing pad 50a The RP is pressed against the tube surface 42. When the swing member 50b is tilted,
Interlocking pin 51 provided near the upper end of swing member 50b
Moves the lower end 66b of the movable guide 66 to the CRT engine 2
Since the movable guide 66 is pushed into the main body, the torsion spring 66
The exposure posture is switched to the exposure posture against the urging force of c.

At the time of the exposure operation in which the first attitude control cam mechanism 52 is in the second state, as described above, the pressure roller 46 is, as described above, a total of two (that is, two) connected to each of the pair of swinging pieces 52b. Left and right) coil springs 60c, 60d
Roll paper RP is pressed against the peripheral surface of the exposure operation roller 44 on the basis of the biasing force described above, but there is a difference in biasing force (that is, elastic restoring force) between the left and right coil springs 60c and 60d. Is provided with a biasing force adjusting mechanism for correcting this and making it equal.

In this embodiment, this urging force adjusting mechanism
It is provided only in the coil spring 60c located on the front side when standing in front of the photosensitive material processing apparatus. As shown in FIG. 6, the biasing force adjusting mechanism includes a first posture control cam mechanism 5.
It comprises a fixed plate 57 that can be fixed to the two box-shaped main bodies 52a, and a movable plate 58 that is movably supported on the fixed plate 57 along the direction in which the coil spring 60c extends. Movable plate 58
The two moving directions of the fixing plate 57 with respect to the fixing plate 57 are as follows: two screws that penetrate the fixing plate 57 from two places of the fixing plate 57 and protrude toward the main body 52a; and a long hole formed in the movable plate 58 to receive these screws. Thus, the direction is limited to the direction along the extension direction of the coil spring 60c. By tightening the two screws, the relative movement of the movable plate 58 with respect to the fixed plate 57 is restricted. Further, a contact piece 58a that can contact the tip of the adjustment screw 57a is provided upright from the movable plate 58.

One end of the coil spring 60c is connected to the movable plate 58, and the movable plate 58 is constantly urged toward the pressure roller 46 by the coil spring 60c. Depending on the amount of protrusion
The relative position of the movable plate 58 with respect to the fixed plate 57 is determined. Therefore, after the two screws fixing the fixed plate 57 of the movable plate 58 are loosened, the adjusting screw 57a is screwed on the fixed plate 57 to adjust the adjusting screw 57a from the fixed plate 57a.
By increasing the amount of protrusion of the tip of the movable plate 58, the movable plate 58
6, the elastic restoring force of the coil spring 60c can be substantially increased, and if the adjusting screw 57a is screwed in the opposite direction, the movable plate 58 will only be screwed forward. The pressing roller 4 is pressed by the urging force of the spring 60c.
By displacing to the sixth side, the elastic restoring force of the coil spring 60c can be set substantially lower again. Further, the fixing plate 57
A fixing screw 59 is provided on the fixing plate 57 as a coarse adjusting means for changing the position of the fixing plate 59 with respect to the box-shaped main body 52a. In the exposure operation section 40, the pressure roller 46 and the exposure operation roller 44 are main components of the photographic paper transport mechanism.

(Structure of paper transport direction switching unit) In the paper transport direction switching unit 70, the photographic paper transport line further downstream than the exposure operation unit 40 in the photographic paper transport direction is connected to the transport line to the cutter unit 80 and the second The path branches to the transfer line to the loop box RB2, but since any transfer line is selected, the second path switching guide 74
Is determined by

As shown in FIGS. 12 (a) and 12 (b), the second path switching guide 74 has a control arm 75 which can swing around the fixed axis X5 and a swingable arm around the axis X6. And a simple loop guide 76. Control arm 75
, A cutter guide 75a and a swing shaft 75b are fixed, and a second pressure roller 75c is rotatably attached to the swing shaft 75b. Through the swing of the control arm 75, the guide surface provided on the cutter guide 75a follows the transport line to the cutter unit 80, and the second pressure roller 75c presses the roll paper RP against the second feed roller 72. become. The loop guide 76 that can swing around the axis X6 independent of the control arm 75 is formed with a long hole 76a extending linearly, and the swing shaft 75b passes through the long hole 76a. I have. With this structure, the swing of the control arm 75, and consequently, the movement of the swing shaft 75b is controlled by the axis X6 of the loop guide 76.
Brings the swing around. The loop guide 76 is also provided with a guide surface for the roll paper RP. The swing surface of the loop guide 76 allows the guide surface to follow the fixed guide 79 connected to the second loop box RB2. Since the relative movement of the loop guide 76 with respect to the control arm 71 is limited to the inside of the elongated hole 76a, when the shaft 75b moves in an arc around the axis X5 based on the swing of the control arm 75, it is The loop guide 76 is forcibly rocked around the axis X6, and as a result, the approach path of the leading end of the roll paper RP is distributed.

As described above, the control position of the cutter guide 75a, the loop guide 76, and the second pressure roller 75c is set by the swing displacement of the control arm 75. The swing of the control arm 75 is in the second posture. This is realized by the control cam mechanism 77. The second attitude control cam mechanism 77 is composed of an action portion 75e as a cam follower provided at a free end of the control arm 75, and a cam body 78 which is rotated in a stepwise manner at a constant angle around the axis X7. It is configured.

The action portion 75e is formed using a ball bearing so as to have a rotatable outer peripheral portion. The control arm 75 is configured such that the action portion 75e is always cam-operated by a torsion coil spring provided around the axis X5. It is urged so as to be close to the axis X7 of the body 78. In the cam body 78, a first cam surface 78a, a second cam surface 78b, a third cam surface 78c, and a fourth cam surface 78d are provided in a circumferential region of the axis X7, which is substantially 90 ° out of phase with each other. Is formed. The first cam surface 78a, the second cam surface 78b, and the fourth cam surface 78d have an arc shape of the axis X7. The first cam surface 78a is formed with the largest radius, and the second cam surface 78b is formed with the smallest radius. The fourth cam surface 78d is formed with a slightly larger radius than the second cam surface 78b. The third cam surface 78c is formed as a linear surface connecting the second cam surface 78b and the fourth cam surface 78d, and is formed between the first cam surface 78a and the second cam surface 78b and between the first cam surface 78a and the first cam surface 78a. Fourth cam surface 78
A transition surface connecting them is formed between d.

As the cam body 98 rotates by 90 °, the action portion 75e rolls on each cam surface, and the swing position of the control arm 75 changes. The position of the cam body 98 is detected by detecting the detected body 78h attached to the cam body 98 and the cam body 98.
Is performed by four sensors (here, magnetic sensors) arranged every 90 degrees. Although the third cam surface 78c creates a state in which the second pressure roller 75c is in close contact with the second feed roller 72, the control arm 75 is rotated counterclockwise with respect to FIG. It is limited by the contact with the two-feed roller 72, and in that state, the action portion 75e is floating from the third cam surface 78c.

The cam body 7 is driven by a DC motor (not shown).
The second path switching guide 74 is set in the following state by sequentially rotating the guide paths 8 by 90 ° each other; in the first state shown in FIG. Direction, the action portion 75e of the control arm 75 is the first cam surface 7
8a. In this first state, the second
At the same time that the pressure roller 75c is sufficiently separated from the second feed roller 72, the loop guide 76 is raised upward, and the leading end portion 76b of the guide surface of the loop guide 76 becomes
It is located higher than the tip 73 a of the fixed guide 73 connected to the cutter unit 80 and is close to the peripheral surface of the second feed roller 72. The guide surface of the cutter guide 75a is also located at a position distant from the photographic paper transport line to the cutter unit 80. When the roll paper RP is fed from the exposure operation unit 40 side in this state, the leading end of the roll paper RP slides down on the guide surface of the loop guide 76, and
Proceed from the fixed guide 79 to the second loop box RB2,
Here, a save loop is formed.

In the second state shown in FIG. 12B, the cam body 78 is directed leftward in the drawing, and the action portion 75e of the control arm 75 is supported by the second cam surface 78b. In the second state, the second pressure roller 75c is still separated from the second feed roller 72, but the guide surface of the cutter guide 75a is in a posture along the photographic paper transport line to the cutter unit 80. The loop guide 76 is slightly tilted, and the leading end 76b of the guide surface of the loop guide 76 is
The fixed guide 73 is retracted below the distal end 73a. When the roll paper RP is fed from the exposure operation unit 40 side in this state, the leading end of the roll paper RP is fixed to the fixed guide 73 by the guide surface of the cutter guide 75a.
Will be guided to. Incidentally, as described above, the loop guide 76
, The front end portion 76b of the guide surface of the loop guide 76 and the front end 73a of the fixed guide 73 extend so as to compensate for the gap therebetween. It has the shape of a comb. Such a structure extending so as to compensate for a gap for relative movement with temporary intersection is provided by the second pressure roller 75.
c is also employed between the peripheral surface of the fixed guide 73 and the front end 73a of the fixed guide 73.

In the third state shown in FIG. 13A, the cam body 78 faces downward in the drawing, and the action portion 75e of the control arm 75 is lowered to the vicinity of the third cam surface 78c. Third
The main area of the cam surface 78c is closer to the axis X7 than the other cam surfaces, and in this third state, the position of the control arm 75 is maintained by the contact of the second pressure roller 75c with the second feed roller 72. ing. However, the postures of the cutter guide 75a and the loop guide 76 are essentially the same as in the second state. When the roll paper RP is switched from the second state in which the roll paper RP is guided by the fixed guide 73 to the third state, the roll paper RP is directly held between the second pressure roller 75c and the second feed roller 72. Therefore, when the second feed roller 72 is driven forward (counterclockwise in the figure), the roll paper RP is sent toward the cutter unit 80, and the second feed roller 72 is driven reversely (clockwise in the figure). As a result, the cutter unit 80 is pulled back toward the exposure operation unit “40”.

In the fourth state shown in FIG. 13 (b), the cam 78 is turned rightward in the drawing, and the action portion 75e of the control arm 75 is supported by the fourth cam surface 78d. The fourth state is substantially the same as the second state, and the second pressure roller 75c is separated from the second feed roller 72 again.
The guide surface of the cutter guide 75a is the cutter unit 8
0, and the leading end portion 76b of the guide surface of the loop guide 76 is retracted below the leading end 73a of the fixed guide 73. In this state, the roll paper RP once sent to the cutter unit 80 side can be pulled back toward the exposure operation unit 40 by the exposure operation roller 44 of the exposure operation unit 40. In the third state, the guide surface of the cutter guide 75a approaches the photographic paper transport line less than in the second state because the roll paper RP is pulled out from the fixed guide 73 in this state. The fact that the fourth cam surface 78d that creates this state is formed farther from the axis X7 than the second cam surface 78b is also a secondary factor that makes the transition from the fourth cam surface 78d to the first cam surface 78a smooth. There is also a positive effect. Since each cam surface has an appropriate effective length, even if the DC motor for rotating the cam body 78 slightly overruns from a predetermined angular position, the position of the action portion 75e, and consequently control. There is no effect on the angle of the arm 75. In the paper transport direction switching unit 70, the second pressure roller 75c and the second feed roller 72 are main components of the photographic paper transport mechanism.

(Cutter Unit) As shown in FIG. 14, a cutter unit 80 capable of cutting the roll paper RP on the transport path is provided downstream of the paper transport direction switching unit 70. The cutter unit 80 is located at the most downstream of the digital printing section 1. Then, the cutter unit 80 in the photographic paper transport line
An outlet transport unit 90 for transporting the cut paper SP is provided downstream of the printer. Exit transport unit 90
Are fixed to the frame of the photosensitive material processing apparatus.

As shown in FIG. 2, downstream of the exit transport unit 90 in the photographic paper transport direction, the exit transport unit 9 is provided.
0 and the horizontal transport unit 105 arranged adjacent thereto
a, a cut paper transport unit 10 composed of a vertical transport unit 105c that transports the paper SP from the outlet to the entrance of the development processing unit 300 positioned vertically downward.
5, the cut paper SP cut by the cutter unit 80 can be transported to the development processing unit 300.

(Configuration of Paper Centering Mechanism) As shown in FIG. 3 and FIG.
A pair of movable first rollers provided upstream of the tube surface in the photographic paper transport direction and further upstream of the exposure operation roller.
Paper centering mechanism 1 including width regulating guides 101, 101 and a pair of similarly movable second width regulating guides 102, 102 provided downstream of tube surface 42 in the photographic paper transport direction.
00 is provided.

As shown in FIG. 15, the first width regulating guides 101, 101 and the second width regulating guides 102, 1
One end of 02 is screw-fitted onto guide rods 103 and 104 formed as feed screws, and the other end is a groove capable of guiding the printing paper in the width direction by inserting the side end of the printing paper. 101a and 102a are provided. First width regulating guides 101, 101 and second width regulating guides 102, 10
2 is prevented from rotating by a slide guide (not shown), and is configured to linearly move by rotation of the guide rods 103 and 104. Note that the feed screw portion formed on the guide rods 103 and 104 is
Are formed in opposite directions with respect to the center in the horizontal direction (the center of line exposure), and the grooves facing each other approach or move away from each other by the rotation of each guide rod.
Since the two guide rods 103 and 104 are connected by a timing belt, when one of the guide rods 104 is rotated by a stepping motor or the like, the first and second width regulating guides (101, 101 and 1) are rotated.
02, 102), the same amount of space is changed at the same time, and the center of the left and right width regulating guides of the two always coincides with the center of the tube surface 42. First and second width regulation guides (101, 101 and 102, 10
The interval created by 2), that is, the guide width, will be described in detail later in the centering operation.
The width is set to a pass width having a value wider than the reference width defined by the S standard by an allowable error or a centering width equal to or smaller than the reference width of photographic paper.

Hereinafter, the operation of the line digital printer having the above-described configuration will be described with reference to the schematic diagram of FIG. 16 and the flowchart of FIG. 17; in the schematic diagram of FIG. Are represented by symbols and solid and dotted lines. For example, as for the paper loading unit 20, a state in which the first pressure roller 26 is in close contact with the first feed roller 22 is ST-1, and a state in which the first pressure roller 26 is detached from the first feed roller 22 is ST-2. The state in which the loop roller 28 enters the first loop box RB1 area beyond the photographic paper transport line is referred to as ST-1, and the state in which the loop roller 28a is separated from the first loop box RB1 area is referred to as ST-2. Regarding the exposure operation unit 40, the state in which the pressure roller 46 constituting the transport mechanism in this area is in close contact with the exposure operation roller 44 is ST-1, and the state in which the pressure roller 46 is detached from the exposure operation roller 44 is ST.
ST-2 when the pressing pad 50a presses the roll paper RP against the tube surface, and ST when the pressing pad 50a is separated from the roll paper RP.
-2. Regarding the paper transport direction switching unit 70,
The state in which the second pressing roller 75c is in close contact with the second feed roller 72 is ST-1, the state in which the second pressing roller 75c is separated from the second feed roller 72 is ST-2, and the loop guide 76 holds the roll paper RP. The state of being guided to the second loop box RB2 is referred to as ST-1, and the loop guide 7
The state where 5c is separated from the photographic paper transport line is ST-2. Further, as the stop position of the leading end of the roll paper RP, the stop point about 10 mm before the cutter unit 80 is set to 1-P, and the stop point on the cutting line of the cutter unit is set to 2-P. Further, a stop point separated from the irradiation point of the exposure unit by a standard size exposure length: L1 to the downstream side in the photographic paper transport direction is set to 3-P,
Exposure length for a predetermined number of exposures when a plurality of exposures are made: The stop point on the retraction line is set to be 5-x the downstream side in the photographic paper transport direction.
P. 4-P is a stop point when the leading end of the roll paper RP is returned to the upstream side from the paper transport direction switching unit 70 and enters the retraction line due to non-standard exposure processing.

When the line exposure type digital printer is started, the leading end of the roll paper RP pulled out from the paper magazine is fed out until reaching the point 1-P, and the exposure length of one time is sufficiently added to the first loop box. A startup process is performed to form a loop of a predetermined length having a satisfactory length (# 2). Next, once the roll paper RP in the exposure area is in a free state,
In steps 1 and 102, a paper centering process for forcibly centering the roll paper RP is performed (# 4). It is determined whether the front end region of the roll paper RP is exposed, that is, whether or not fogging has occurred (# 6). If there is fogging, fogging processing for cutting the fog portion by the cutter unit 80 is performed (# 10). If there is no fog, pre-exposure processing is performed to convey the roll paper RP so that the irradiation point of the exposure unit and the leading end of the roll paper RP have almost the same exposure length (# 8). Next, the exposure process is started, and before that, it is checked whether it is a normal exposure or an exceptional exposure such as a specially large print (requiring a long exposure distance) or multiple prints. (# 12), the standard exposure processing of # 14 for normal exposure, the exceptional length exposure processing of # 16 for large prints of exceptional exposure, and the multiple exposures of # 18 for multiple prints Perform exposure processing. In any case, an image based on the image data is printed on the roll paper RP by performing line exposure at the irradiation point while returning the roll paper RP toward the first paper box.

In order to send the exposed area of the roll paper RP as cut paper to the developing section 300, a paper cut process is performed by a cutter unit (# 2).
0). In this paper cutting process, the basic loop in the first loop box RB1 is supplemented by the amount used for printing. It is checked whether border cut is necessary for the cut paper SP (# 22). If border cut is necessary, border cut processing is performed (# 24). In any case, the cut paper is sent to the development processing unit 300. Sent (# 26).

Thus, since a series of printing operations is completed, it is checked whether or not further printing operations are necessary (# 28). When the printing operations are completed, an end process such as returning the roll paper RP to the paper magazine again is performed. (# 32). If the printing operation continues, a photographic paper loop of a basic amount is formed in the first loop box (# 30), and the process returns to # 12.

Next, the main processing routine shown in the flowchart of FIG. 17 will be described in detail with reference to the flowchart. In the startup processing routine shown in FIG. 18, the processing routine is drawn from the paper magazine PM1. The roll paper RP is conveyed by forward rotation of the first feed roller until the leading end reaches point 1-P (# 1).
21). First feed roller 2 from paper magazine PM1
The transfer of photographic paper up to 2 is performed by a transfer mechanism. Subsequently, the pressure roller 46 is switched to the state ST-1, and the roll paper RP is sandwiched between the roller 44 and the exposure operation roller 44 (# 122).
1 by switching the loop roller 28a to the state ST-1.
A preparation for forming a photographic paper loop in the first loop box RB1 is made (# 123). When the first feed roller 22 is driven to rotate forward while the roll paper RP is pressed and held by the pressure roller 46 and the exposure operation roller 44, the roll paper RP pulled out from the paper magazine PM1 is transferred to the first loop box RB1. As a result, a loop is formed in the first loop box RB1 (# 12)
4). This loop formation ends when the sensor detects the loop. The loop formed in this way is called a basic loop, and is maintained as much as possible during the printing operation. Subsequently, the first feed roller 22 is further driven forward (# 125), and in this embodiment, the roll paper RP is further rolled by a predetermined length which is a value obtained by subtracting 50 mm from the length of the print to be created next. When the first feed roller is fed to the one loop box RB1 (# 126), the first feed roller is stopped (# 127).

In the paper centering processing routine shown in FIG. 19, the pressure roller 46 is switched to the state ST-2, a gap is formed between the pressure roller 46 and the exposure operation roller 44, and the roll paper RP around the exposure unit is set in the free state. (# 41). At this time, the first width regulating guide 101 and the second width regulating guide 102
The guide width created by each of the guide grooves 10
The guide width is set to a predetermined value (pass width) wider than the reference width defined by the JIS standard of the photographic paper guided by 1a and 102a by an allowable error. It is set to a predetermined value (centering width) which is equal to or less than the reference width of the photographic paper (# 42). As a result, the center axis of the roll paper RP is forcibly moved to the first width regulating guide 1.
01 coincides with the center of the guide width created by the second width regulating guide 102, and as a result, coincides with the perpendicular bisector of the line exposure locus. When the centering is completed, the press roller 46 is switched to the state ST-1, and the roll paper RP is pressed and held by sandwiching the roll paper RP with the exposure operation roller 44 (# 4).
3) After that, the motor 105 is operated again to set the guide width created by the first width regulating guide 101 and the second width regulating guide 102 to a predetermined value (passing width) wider than the reference width of the printing paper (# 44).

In the pre-exposure processing routine shown in FIG. 20, the second pressure roller 75c of the paper transport direction switching unit 70 is switched to the state ST-1 (# 81), and the second feed roller 7
2 and the pressure roller 75c of the exposure unit is switched to the state ST-2 (# 8).
2), the second feed roller 72 is driven to rotate forward (# 83), and the roll paper RP is transported toward the cutter unit 80;
(# 84), the second feed roller 72 is stopped (# 85). Next, the pressure roller 46 is set to the state S.
After switching to T-1 (# 86), the second pressure roller 7
5c is switched to the state ST-2 (# 87), and the conveyance of the next roll paper RP is entrusted to the exposure operation roller 44.

In the standard exposure processing routine shown in FIG.
First, the exposure operation roller 44 is driven to rotate in the reverse direction (# 141).
The roll paper RP is fed back to the first loop box RB1, and the length from the leading end of the roll paper RP to the irradiation point of the exposure unit is a standard exposure length: L1 (a length for creating a standard print). , Ie, at the point 3-P (# 142), the exposure operation roller 44
Is stopped (# 143). Next, the pressing pad 50
a is switched to the state ST-1 (# 144), and the emulsion surface of the photographic paper is brought into close contact with the tube surface 42. At the same time as the exposure operation roller 44 is driven to rotate in reverse (# 145), the CRT engine 2 is driven in synchronization with the operation of the exposure operation roller 44, and the R, G, and B are input based on image data input in advance.
The desired image is printed on the roll paper RP by repeating the line exposure performed by sweeping each light beam (# 146). When the exposure is completed, the exposure operation roller 44 is stopped (# 147), the pressing pad 50a is switched to the state ST-2 (# 148), and the close contact of the roll paper RP with the tube surface 42 is released.

In the exceptional length exposure processing routine, the length of the roll paper RP to be on standby downstream (in the development processing section) in the transport direction from the irradiation point of the exposure section becomes longer. By sending paper RP not to the cutter unit but to the second loop box to form a loop,
The roll paper RP of a required length is temporarily stored. At the time of exposure, the CRT engine 2 performs line exposure while pulling up the roll paper RP from the second loop box by driving the exposure operation roller in the reverse direction. Further, in the multiple-sheet exposure processing routine, in order to continuously print a plurality of images on the roll paper RP, the roll paper RP having a length sufficient to print the plurality of images is downstream of the irradiation point of the exposure unit in the transport direction. Side (the development processing unit side). Therefore, also in this processing, the roll paper RP of a required length is temporarily stored by sending the roll paper RP to the second loop box instead of directing it to the cutter unit to form a loop. At the time of exposure, a plurality of print images are printed on the roll paper RP by the CRT engine 2 while pulling up the roll paper RP from the second loop box by driving the exposure operation roller in the reverse direction.

(Modification) In the above-described embodiment, in the paper centering mechanism 100, a pair of left and right width regulating guides which move in the near and far directions are arranged one by one on both sides of the tube surface 42 in the photographic paper transport direction. Although the configuration is employed, a configuration in which only a pair of width regulating guides having a large guide length in the photographic paper transport direction may be arranged in the vicinity of the tube surface 42 instead of this. The important point of the present invention is that the roll paper RP released from the transport mechanism, for example, the combination of the exposure operation roller and the pressure roller, is sandwiched from the left and right, forcibly centered, and then held again by the transport mechanism. Various modifications can be made without departing from the scope of the present invention.

[Brief description of the drawings]

FIG. 1 is an external perspective view of a photographic processing apparatus employing the technology of the present invention.

FIG. 2 is a schematic cross-sectional view of the photographic processing apparatus according to FIG.

FIG. 3 is a schematic cross-sectional view of a digital print section.

FIG. 4 is a schematic diagram illustrating the movement of a paper loading unit.

FIG. 5 is a plan view of an exposure operation unit.

FIG. 6 is a left side view of the exposure operation unit.

FIG. 7 is a right side view of the exposure operation unit.

FIG. 8 is a perspective view showing a part of an exposure operation unit.

FIG. 9 is a schematic diagram illustrating the movement of a first attitude control cam mechanism.

FIG. 10 is a schematic diagram illustrating the movement of a first attitude control cam mechanism.

FIG. 11 is a schematic diagram illustrating the operation of the paper bypass mechanism.

FIG. 12 is a schematic diagram illustrating the movement of a paper transport direction switching unit.

FIG. 13 is a schematic diagram illustrating the operation of a paper transport direction switching unit.

FIG. 14 is a schematic view showing the arrangement of cutter units.

FIG. 15 is a perspective view of a paper centering mechanism.

FIG. 16 is a schematic diagram illustrating the movement of each mechanism in a photographic paper transport line.

FIG. 17 is a flowchart illustrating the operation of a digital print unit.

FIG. 18 is a flowchart showing a startup processing routine.

FIG. 19 is a flowchart showing a paper centering processing routine;

FIG. 20 is a flowchart showing a pre-exposure processing routine;

FIG. 21 is a flowchart showing a standard exposure processing routine;

[Explanation of symbols]

 RP roll paper (printing paper) 20 paper loading section 22 first feed roller 26 first pressure roller 28a loop roller 40 exposure operation section 44 exposure operation roller 46 pressure roller 70 paper transport direction switching section 72 second feed roller 75c second pressure Roller 76 Loop guide 100 Paper centering mechanism 101 Width regulation guide (upstream side) 102 Width regulation guide (downstream side)

Claims (5)

[Claims] 1. An optical printer for printing an image on photographic paper by irradiating light based on image data onto photographic paper conveyed by pressure by a conveying mechanism while being guided by movable width-regulating guides arranged on both right and left sides. In the paper centering method, a first step of setting a guide width created by the left and right width regulating guides to a predetermined value wider than the width of the photographic paper; and while being guided by the width regulating guide set to the predetermined value. A second step of transporting the photographic paper to the printing area, a third step of releasing the pressure of the transport mechanism for transport, and a guide width of the left and right width regulating guides being set to a predetermined value equal to or less than the width of the photographic paper. A fourth step of setting; a fifth step of re-pressing the transport mechanism; and setting a guide width of the left and right width regulating guides to a predetermined value wider than the width of the printing paper. Sixth step and, centering method of the printing paper, characterized in that it consists of that. 2. A pair of left and right movable width regulating guides are arranged upstream and downstream in a photographic paper conveyance direction with an irradiation point interposed therebetween, and both movable width regulating guides move synchronously. The method for centering photographic paper according to claim 1. 3. A step of carrying out the third step to the sixth step after the carrying step of feeding an area to be exposed of the photographic paper beyond the irradiation point, and thereafter, exposing the photographic paper in a carrying step of pulling back the photographic paper. 3. The image printing is performed by irradiating a region to be illuminated with light.
3. The method for centering photographic paper described in 1. above. 4. A transport mechanism for compressing and transporting photographic paper, an exposure unit for printing an image on the photographic paper by irradiating light based on image data to the photographic paper compressed and transported by the transport mechanism, and an exposing unit. In an optical digital printer having a movable width regulating guide for guiding the left and right sides of the photographic paper passing therethrough, the left and right width regulating guides are a guide position for creating a guide width wider than the width of the photographic paper and a width of the photographic paper or less. The guide width can be set to a centering position for producing the guide width, and the left and right width regulating guides are shifted from the guide position to the centering position in a state where the pressure of the photographic paper by the transport mechanism is released. An optical digital printer characterized in that it performs dispensing. 5. The exposure unit is of a line exposure type, and the pair of left and right movable width regulating guides are disposed upstream and downstream in the photographic paper transport direction with the exposure unit interposed therebetween. The optical digital printer according to claim 4, wherein the regulation guide is moved by a common driving source.