JPH02264235A - Scanning exposure device - Google Patents

Abstract

PURPOSE:To prevent a striped pattern from being formed and to enable excellent image formation by forming a transparent fluororesin layer on the contact surface of exposure surface glass which contacts the photosensitive surface of a photosensitive material and controls the photosensitive surface of the photosensitive material to an exposure position. CONSTITUTION:This device has conveyor rollers 58 and 60 for the photosensitive material A which are arranged on and below the exposure position 46a at an exposure part 46, the exposure surface glass 54 which regulates the exposure position 46a, and a pressure plate 56 as a pressing means for pressing the photosensitive surface of the photosensitive material A against the exposure surface glass 54. Then the transparent fluororesin layer 54a is formed on the contact surface of the exposure surface glass 54 which contacts the photosensitive surface of the photosensitive material. Therefore, the distortion, diffraction, and irregular reflection of reflected light due to the uneven contact (press) movement between the photosensitive surface of the photosensitive material A and the surface of the exposure surface glass 54 are suppressed. Consequently, excellent exposure is performed without any light interference.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention provides a method for defining the photosensitive surface of a photosensitive material at an image forming position,
The present invention relates to a scanning exposure device that scans and conveys the photosensitive material to expose it.

<Conventional technology> Exposure devices used in various copying machines, printers, printing presses, etc., have the following advantages: ■ The exposure area can be made smaller and the exposure device can be made more compact, ■ Light source Slit scanning exposure is often used because it can reduce the amount of light.

Such a scanning exposure device includes, for example, an exposure light source that irradiates the document while scanning the bottom surface of the document placed on the document table, and a plurality of mirrors that reflect light reflected from the document in a predetermined direction. It has a conveyance means etc. that scans and conveys the photosensitive material at the image formation position of an imaging lens that forms an image of light on the photosensitive surface of the photosensitive material, that is, at the exposure position, and scans and exposes the photosensitive material being scanned and conveyed at the image formation position. It is something to do.

In such a scanning exposure apparatus, an exposure light source illuminates a document while scanning at a predetermined speed.

The reflected light from the original (hereinafter referred to as reflected light) is reflected in a predetermined direction by at least one movable mirror, enters the imaging lens, and forms an image on the photosensitive surface of the photosensitive material. The light is dimmed to match.

The reflected light that has passed through the imaging lens passes through a slit placed in front of the exposure position (on the upstream side in the direction of travel of the reflected light).
An image is formed on the photosensitive surface of the photosensitive material, and the photosensitive material, which is transported in synchronization with the scanning of the exposure light source, is exposed.

<Problems to be Solved by the Invention> Incidentally, in an image forming apparatus using such a scanning exposure device, scale-like striped patterns are occasionally formed on the obtained image, and it is difficult to obtain a stable and good image. The problem is that it is not possible to obtain

The inventors of the present invention have made extensive studies to prevent such deterioration in image quality, and have discovered that the cause of this deterioration in image quality lies in the exposure section that exposes the photosensitive material.

FIG. 4 shows a schematic diagram of an exposure section in such a scanning exposure apparatus.

In the exposure section 200 shown in FIG.
is scanned and conveyed by conveyance rollers 202 and 204 arranged above and below the exposure position 200a, while
Proceeding along the optical path, passing through the slit 206 and reaching the exposure position 20
It is exposed to the reflected light of the original imaged at 0a.

Therefore, it goes without saying that the exposure position 200a, which is the imaging position of the original image, needs to be accurately defined.

Therefore, at the exposure position 200a, there is a transparent exposure surface glass 20 that defines the photosensitive surface of the photosensitive material A at the exposure position 200a.
8 and a pressing plate 210 for pressing the photosensitive material A against the exposure surface glass 208, the photosensitive material A is pressed against the pressing plate 21.
By being scanned and conveyed while being pressed against the exposure surface glass 208 at 0, the exposure position 200a is accurately conveyed,
Exposure is performed by reflected light that travels along the optical path and forms an image at the exposure position 200a.

The inventors of the present invention further investigated the above-mentioned striped pattern caused by the exposure section 200, and found that the reason for its formation was that the photosensitive material A was conveyed while being pressed against the exposure surface glass 208 and was exposed to scanning light. They discovered that the problem lies in the interference of light generated by

In other words, since the photosensitive material A is accurately defined at the exposure position 200a as described above, the photosensitive material A is conveyed while being pressed against the exposure surface glass 208 by the pressing plate 210.
The photosensitive surface is constantly rubbed against the exposure surface glass 208 and exposed.

Here, the photosensitive surface of the photosensitive material A and the exposure surface glass 208
Both surfaces are not perfectly flat, but have irregularities on a microscopic level, and during exposure, the exposure surface glass 208 and the photosensitive surface of the photosensitive material A have their respective concave and convex portions contacting (pressing) each other. Move.

Therefore, distortion, diffraction 9, diffuse reflection, etc. of the light reflected from the original occur between the concave and convex portions of the exposure surface glass 208 and the photosensitive surface of the photosensitive material A, and the interference of these lights causes damage to the photosensitive material. A is exposed unnecessarily and the striped pattern described above occurs.

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of the prior art described above, and in order to define the photosensitive surface of the photosensitive material at an exposure position, the photosensitive surface of the photosensitive material is conveyed under pressure against an exposure surface glass in an exposure section. A scanning exposure device that does not cause exposure defects such as striped patterns due to light interference, which occurs when the photosensitive surface of a photosensitive material is conveyed while being pressed against an exposure surface glass and subjected to scanning exposure. It is about providing.

Means for Solving the Problems In order to achieve the above object, the present inventors have made extensive studies and have solved the above-mentioned cause of poor exposure by providing a fluororesin layer on the surface of the exposure glass that contacts the photosensitive material. The present inventors have discovered that the interference of light can be suppressed, and have accomplished the present invention.

That is, the present invention includes an exposure light source, a plurality of mirrors,
A scanning exposure device that scans and exposes the photosensitive material, comprising an imaging lens and a scanning conveyance means that scans and conveys the photosensitive material defined at the image formation position by the imaging lens, the exposure surface of the photosensitive material being scanned and exposed. a transparent exposure surface glass for defining the image forming position at the image forming position; and a pressing means for pressing the photosensitive surface of the photosensitive material against the exposure surface glass, the surface of the exposure surface glass contacting the photosensitive material. The present invention provides a scanning exposure device characterized in that a transparent fluororesin layer is provided.

<Operation of the Invention> The scanning exposure device of the present invention has a transparent fluororesin layer formed on the contact surface of the exposure surface glass, which defines the photosensitive surface of the photosensitive material at the exposure position, with the photosensitive surface of the photosensitive material. .

Therefore, light distortion and diffraction are caused by the contact (pressure) movement of the unevenness between the photosensitive surface of the photosensitive material and the exposure glass surface, which occurs when the photosensitive material is scanned and conveyed while being pressed against the exposure glass surface and exposed. , can suppress diffused reflection, etc.
It is possible to perform good exposure without light interference due to these, and it is possible to perform scaly-like images that rarely occur in image forming apparatuses that use scanning exposure devices that perform scanning exposure by scanning and transporting photosensitive materials. Stable image formation can be performed at all times without the occurrence of striped patterns.

<Embodiments> Hereinafter, a scanning exposure apparatus of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.

FIG. 1 shows a preferred embodiment of the scanning exposure apparatus of the present invention.

The scanning exposure device 150 shown in FIG. 1 is configured to move an image of a document 130 placed on a document table 80 made of glass or the like and fixed to the document table 80 by a document holder 15 using a pressing plate 56 on the exposure surface glass. While being pressed against the plate 54, the transport rollers 58 and 6
The photosensitive material A, which is being scanned and conveyed at zero, is subjected to slit scanning exposure at the exposure position 46a.

Such a scanning exposure apparatus 150 includes a light source unit that has an exposure light source 166, a reflector 168, and a mirror 170 and is movable in the scanning direction indicated by arrow a, and a light source unit that is movable in the same direction at 1/2 the speed of the light source unit. A mirror unit having mirrors 174° and 176 working in eight shifts, a lens unit 156 movable back and forth along the optical path, a sensor 160, and a photosensitive material A are transported to a predetermined exposure position 46a and subjected to exposure. It is composed of an exposure section 46 and a shutter 158 that switches the optical path between the exposure section 46 side and the sensor 160 side.

The light source unit scans the lower surface of the document table 80 in the direction of arrow a by means not shown, and scans the document 1 using an exposure light source 166.
30 irradiation.

The exposure light source 166 is a halogen lamp, a fluorescent lamp, or the like, and the reflector 168 is formed with a slit 172 through which light reflected from the document (hereinafter referred to as reflected light) passes.

The mirror unit has two mirrors 174 and 176, and is mirrored 1/2 in the same direction as the light source unit by means not shown.
It moves at a speed of 2 and reflects the reflected light in a predetermined direction shown as an optical path.

The lens unit 156 is a combination of an imaging lens and a light control device that adjusts the amount and quality of reflected light, and includes a front lens group 178 and a rear lens group 180, which are imaging lenses, 178 and the rear group 180, a first color filter 182 consisting of a clear through filter, a cyan filter, and a magenta filter, a fixed aperture 184, and a second color filter 186 consisting of a clear through filter, a cyan filter, and a yellow filter; It has a variable aperture consisting of a pair of aperture plates 188a and 188b, which is arranged behind the rear lens group 180.

This lens unit 156 is movable in the front and rear directions of the optical path, and in the scanning exposure device 150, during exposure, the lens unit 156 can be moved forward to perform enlarged exposure, and also moved backward. This is to perform reduction exposure. Further, if necessary, it is configured to be movable in a direction perpendicular to the optical path on the same plane as the longitudinal direction of the reflected light beam.

Here, the optical system of the scanning exposure device 150 of the present invention is configured such that even when the lens unit 156 is moved, the imaging position of the original image by the imaging lens of the lens unit 156 is is configured to always be at an exposure position 46a defined by an exposure surface glass 54, which will be described later.

The shutter 158 switches the optical path between the sensor 160 side and the exposure section 46 side, and is rotatably supported by a support shaft 190 at a position shown by a solid line and a position shown by a dotted line.

During normal exposure, this shutter 158 is placed at the position shown by the solid line in the figure to direct the optical path to the exposure position 46a, and during pre-scanning, white balance adjustment, etc., it is rotated to the position shown by the dotted line in the figure. sensor 1
Switch to 60 side.

The sensor 160 measures the amount of light, pre-loading, etc. during pre-scanning and white balance, and depending on the measurement results, the type and type of color filter in the lens unit 156 described above is determined.
The amount of insertion, etc., and the amount of light intensity adjustment with the variable aperture are determined,
be adjusted.

The reflected light that has passed through the lens unit 156, has been modulated, and has proceeded along the optical path passes through the slit 194 and enters the exposure section 46, where it forms an image at the exposure position 46a and forms an image on the photosensitive material A.
Expose the photosensitive surface of the

A partially enlarged view of this exposure section 46 is shown in FIG.

In the exposure section 46 shown in FIG.
Conveying rollers 58 and 60 for the photosensitive material A are arranged to sandwich the top and bottom of the photosensitive material A, an exposure surface glass 54 for defining the exposure position 46a, and the photosensitive surface of the photosensitive material A is pressed against the exposure surface glass 54. Pressing plate 5 as a pressing means for
6. Here, the exposure surface glass 54
The pressing plate 56 defines an exposure position 46a, which is the imaging position of a document image having a predetermined slit width, and also constitutes a transport path for the photosensitive material A.

In the scanning exposure apparatus of the present invention, a transparent fluororesin layer 54a is formed on the surface of the exposure surface glass 54 that comes into contact with the photosensitive surface of the photosensitive material A.

In the example shown in FIG. 2, the photosensitive material A is conveyed in the direction of arrow H by conveyance rollers 58 and 60, and is pressed against the exposure surface glass 54 by a pressing plate 56 in the direction of arrow V in the figure for exposure. Its photosensitive surface is defined at position 46a. on the other hand,
The reflected light traveling along the optical path forms an image at the exposure position 46a, and exposes the photosensitive surface of the photosensitive material A.

Here, in the scanning exposure apparatus of the present invention, since the fluororesin layer 54a is formed on the surface of the exposure surface glass 54 that contacts the photosensitive surface of the photosensitive material A, the photosensitive surface of the photosensitive material A is brought into contact with the suppression plate 56. The reflected light is caused by uneven contact (suppression) between the photosensitive surface of the photosensitive material A and the surface of the exposure surface glass 54, which occurs when the photosensitive material A is scanned and conveyed while being pressed against the exposure surface glass 54 for exposure. Distortion, diffraction, diffused reflection, etc. can be suppressed, and good exposure can be performed without interference of light due to these.

Therefore, an image forming apparatus to which the scanning exposure device of the present invention is applied can always form a good image without forming scale-like striped patterns due to the above-mentioned causes.

The fluororesin that can be used in the present invention includes various types such as polytetrafluoroethylene (PTFE), polychlorotrifluoroethylene (PCTFE), polyvinylidene fluoride, and fluoroethylene-propylene copolymer. In the present invention, PTFE is particularly preferably applied.

Various methods can be used to form the fluororesin layer 54a, such as spray coating and gravure coating.

FIG. 3 shows an example in which the above-described scanning exposure device 150 is applied to a silver halide photocopying device.

A silver halide photocopying apparatus 10 (hereinafter referred to as the copying apparatus 10) shown in the figure includes a photosensitive material supply unit 16 on the right side, an exposure unit 18 above it, and a processing unit 20 below it. ing.

Here, the exposure unit 18 is the scanning exposure device 1 described above.
50 is applied.

The photosensitive material supply section unit 16 has a photosensitive material conveyance path within the photosensitive material supply section frame 28, and a pair of magazines 30.32 are removably attached to the upper and lower sides, and photosensitive materials 34.36 are stored inside these magazines. are housed in a roll, respectively, and are taken out from the tip to the photosensitive material supply unit 16. - For example, 34 is a photosensitive material most suitable for copying a color printed original, and 36 is a photosensitive material most suitable for copying a color photographic original.

In front of the magazine 30, a conveying roller 42 for drawing out the photosensitive material 34 and a cutter 44 for cutting the photosensitive material 34 into a predetermined length are arranged.

Between the cutter 44 and the exposure section 46 are photosensitive material conveyance guides 48a, 48b, 48c and conveyance rollers 50, 5.
2 is arranged to guide the cut photosensitive material 34 to the exposure section 46 of the scanning exposure device 150 of the present invention.

A conveyance guide 62 that guides the photosensitive material 34 after exposure vertically downward is arranged below the exposure section 46, and a conveyance guide 66 that branches the conveyance path of the photosensitive material 34 (36) is arranged in the vertical middle part of the conveyance guide 62. A switching guide 64 is provided for switching to the processing section unit 20 via the processing section unit 20.

On the other hand, the magazine 32 disposed below the magazine 30 also has a conveyance roller 68 and a cutter 70 corresponding to the photosensitive material 36, and in front of the magazine 32 there are conveyance guides 2a and 70.
2b and a conveyance roller 74 are arranged to convey the photosensitive material 36 to the conveyance guide 48a.

The exposure section unit 18 has the above-described scanning exposure device 150 applied and arranged in the exposure section frame 98, so the same members are given the same numbers and their explanations will be omitted.

The processing section unit 20 includes a processing section 22 and a drying section 24. A developing tank 102, a bleaching/fixing tank 104, and a washing tank 106 and 108 are successively provided in the processing section 22,
The processing liquid filled inside these allows for development, bleaching,
The photosensitive material 34 (36) that has been fixed and washed with water is sent to the drying section 24.

In the drying section 24, the photosensitive material 34 (36) after being washed with water is dried and sent onto the take-out tray 110.

Hereinafter, the operation of the scanning exposure device 150 of the present invention as well as the operation when copying the original 80 using the copying apparatus 10 will be explained.

First, the original 130 is placed on the original table 80, and the original holder 1
5 is closed.

Next, when the copy magnification is set and a copy start button (not shown) of the copying device 10 is pressed, the exposure light source 166 is turned on.
lights up, the light source unit starts scanning, and pre-scanning begins.

The reflected light enters the mirror 170, is reflected, is reflected by each mirror of the mirror unit that moves in the same direction as the light source unit at 1/2 the scanning speed, and is reflected by the lens unit 15.
6 and is reflected by the shutter 158 to the sensor 1.
60, image information is read by the sensor 160,
Exposure correction conditions are set.

After the pre-scan ends, the light source unit and mirror unit return to the scan start position.

On the other hand, while the above-described prescanning and color filter and aperture correction are being performed, a photosensitive material necessary for copying according to the original 130 is selected.

For example, when the original 130 is a color photographic original, the photosensitive material 36 is selected, and when the transport motor (not shown) is driven, the transport rollers 68 and 74 move the photosensitive material 36.
The cutter 70 feeds out the photosensitive material 3 by a predetermined length.
6 is cut to the required length.

Thereafter, the conveyance motor is driven again to transport the photosensitive material 36.
is sent to the exposure section 46 and waits just before the exposure position 46a.

When the shutter 158 rotates to the position indicated by the solid line to enable exposure and the light source unit starts main scanning of the original 130,
At the same time, the conveyance rollers 58 and 60 of the exposure section 46 start scanning and conveying the photosensitive material 36 in synchronization with the scanning speed of the light source unit.

During main scanning, reflected light that is irradiated onto the light source 166 of the light source unit and reflected by the mirror 170 is transmitted to the light source 170 of the light source unit.
The light is reflected by each mirror of the mirror unit moving in the same direction at a speed of 2, passes through the lens unit 156 whose color and aperture are appropriately adjusted, then passes through the slit 194, and is imaged at the exposure position 46a. The photosensitive material 36 is pressed against the exposure glass 54 by the pressing plate 56 and scanned and conveyed by the roller pair 58 and 60 in synchronization with the light source unit.
Expose the photosensitive surface of the

Here, in the scanning exposure apparatus of the present invention, since the exposure surface glass 54 has the fluororesin layer 54a,
Exposure defects due to light interference, which are caused by the photosensitive material 36 being scanned and conveyed while being pressed against the exposure surface glass 54 and exposed, do not occur.

As this exposure progresses, the photosensitive material 36 is transferred to the conveying roller 58.
and 60 are sent downward through the conveyance guide 62. In this case, the switching guide 64 does not act on the photosensitive material transport path, and the photosensitive material 36 sent from the exposure section 46 moves vertically downward within the transport guide 62.

When all exposure is completed, the shutter 158 rotates to the position shown by the dotted line to close the optical path, and then each conveyance roller temporarily rotates in the opposite direction, and the exposed photosensitive material 36 moves along the conveyance guide 62. It rises and a portion is sent into the conveyance guide 48c.

This reverse conveyance is stopped when the leading end of the photosensitive material 36 is upstream of the switching guide 64. Thereafter, each conveyance roller is rotated again in the same direction as the initial conveyance direction. In this case, the switching guide 64 acts on the photosensitive material conveyance path and sends out the leading end of the photosensitive material 36 to the branch conveyance guide 66.

Therefore, the leading end of the photosensitive material 36 is sent to the processing section 22 of the processing section unit 20 through the branch conveyance guide 66 .

The exposed photosensitive material 36 sent into the processing section 22 is transferred to the developing tank 1.
02, bleached and fixed in a bleaching/fixing tank 104, thoroughly washed with water in a washing tank 106108, and then sent to a drying section 24, and after drying, a take-out tray 110
taken out to the top.

Although the scanning exposure apparatus according to the present invention is configured as described above, the present invention is not limited thereto. Of course, various improvements and changes in design are possible without departing from the gist of the present invention, such as application to a scanning exposure apparatus.

<Effects of the Invention> The scanning exposure device of the present invention has a transparent fluororesin layer formed on the contact surface of the exposure surface glass, which defines the photosensitive surface of the photosensitive material at the exposure position, with the photosensitive surface of the photosensitive material. .

Therefore, light due to the uneven contact (pressure) movement between the photosensitive surface of the photosensitive material and the exposure glass surface, which is generated when the photosensitive surface of the photosensitive material is scanned and conveyed while being pressed against the exposure glass surface, is exposed. Distortion, diffraction, diffused reflection, etc. can be suppressed, and it is possible to perform good exposure without interference of light due to these.

Therefore, in an image forming apparatus to which the scanning exposure device of the present invention is applied, the scale-like striped pattern that rarely occurs in conventional image forming apparatuses does not occur, and good image formation can be performed stably. It is possible to do so.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an example of a scanning exposure apparatus of the present invention. 2 is a partially enlarged view of the exposure section of the scanning exposure apparatus shown in FIG. 1. FIG. FIG. 3 is a schematic diagram of an example in which the scanning exposure apparatus shown in FIG. 1 is applied to a silver halide photocopying apparatus. FIG. 4 is a schematic diagram of an exposure section of a conventional scanning exposure apparatus. Description of symbols 10... Copying device, 15... Document holder, 16... Photosensitive material supply section unit, 18... Exposure section unit, 20... Processing section unit, 22... Processing section, 24... Drying section, 28... Photosensitive material supply section frame, 30.32... Magazine, 34.36... Photosensitive material, 42.68... Conveyance roller, 46... Exposure section, 46a...Exposure position, 54...Exposure surface glass, 54a...Fluororesin layer, 58.60...Conveyance roller, 64...Switching guide, 80...Original table, 98... Exposure section frame, 102... Developer tank, 104... Bleaching/fixing tank, 106.108... Washing tank, 110... Take-out tray, 130... Document, 150... Scanning exposure device, 156... Lens unit, 158... Shutter, 160... Sensor, 166... Exposure light source, 168... Reflector, 70, 174. 176° 72...Slit, 78... Lens front group, 80... Lens rear group, 82... First color filter, 84... Fixed aperture, 86... Second color filter 192. ...Mirror patent applicant Fuji Photo Film Co., Ltd. Representative Patent attorney Minoru Watanabe FIG, 2

Claims (1)

[Claims] (1) An exposure light source, a plurality of mirrors, an imaging lens,
A scanning exposure device that scans and exposes the photosensitive material, the scanning exposure device comprising a scanning conveyance means for scanning and conveying the photosensitive material defined to the image formation position by the imaging lens, and a scanning exposure device that scans and exposes the photosensitive material. and a pressing means for pressing the photosensitive surface of the photosensitive material against the exposure surface glass, and a transparent fluorine-containing material is applied to the surface of the exposure surface glass that contacts the photosensitive material. A scanning exposure device characterized by being provided with a resin layer.