JP2007076029A - Adjustment method and manufacturing method for image printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an adjustment method for an image printer wherein a printing quality practically obtained can be surely improved by adjusting at least one of an object distance and an image plane distance of a focusing lens array. <P>SOLUTION: In the method for adjusting the image printer 1 which utilizes an electrophotographic system and images light from a light emitting panel 10 onto a photoreceptor drum 110 by the focusing lens array 40, a process of forming a sensible image by the image printer 1 and a process of shifting at least one of an interval between the focusing lens array 40 and the photoreceptor drum 110 and an interval between the light emitting panel 10 and the focusing lens array 40 are repeated. On the basis of the evaluation of a quality of the sensible image obtained in the repeated processes, at least one of the interval between the focusing lens array 40 and the photoreceptor drum 110 and the interval between the light emitting panel 10 and the focusing lens array 40 is adjusted. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electrophotographic image printing apparatus, and more particularly to an adjustment method and a manufacturing method of an image printing apparatus that writes a latent image on an electro-optical panel in which electro-optical elements such as light emitting elements or light valve elements are arranged.

  In order to write an electrostatic latent image on an image carrier (for example, a photosensitive drum) of an electrophotographic image printing apparatus, for example, an array panel of an electroluminescent element (hereinafter referred to as an “EL element”) or a liquid crystal panel A technology using an electro-optical panel has been developed. In such a technique, generally, a converging lens array is disposed between an electro-optical panel and an image carrier (for example, Patent Documents 1 to 4). As the converging lens array, for example, there is SLA (Selfoc Lens Array) available from Nippon Sheet Glass Co., Ltd. (Selfoc \ SELFOC is a registered trademark of Nippon Sheet Glass Co., Ltd.).

  In such an image printing apparatus, the distance between the electro-optical panel and the converging lens array (object distance) and the distance between the converging lens array and the photosensitive surface of the image carrier (image surface distance) are determined based on the image on the photosensitive surface. It has a great influence on the resolution and, consequently, the print quality. Therefore, a technique for adjusting the object distance and image plane distance of the converging lens array has been proposed. For example, each of Patent Documents 1 to 3 discloses a mechanism for adjusting the image plane distance. In general, these adjustment methods adjust the distance so that the measured distance matches the design value, or the object distance so that the measured object distance matches the measured value of the fixed image plane distance. To adjust. Patent Document 4 discloses a technique for arranging an exposure unit and a converging lens array at a reference position so that a predetermined object distance can be obtained.

  Patent Document 5 discloses a mechanism for adjusting the image plane distance and a mechanism for adjusting the object distance. Also, in Patent Document 5, an image of a light emitting element that has passed through a converging lens array is taken with a camera, and the light emitting element is opposed to the light emitting element so that the camera is in focus and the captured image of the light emitting element becomes clear. A method for adjusting the position of a converging lens array is disclosed.

Japanese Patent No. 3178623 Japanese Patent No. 2944090 Japanese Patent No. 2620639 Japanese Patent No. 2625702 JP-A-1-301269

  However, for a method of adjusting the distance so that the measured distance matches the predetermined value, it is very difficult to measure the distance without error. Further, since there are manufacturing variations in the converging lens array, it is not always possible to improve the resolution when the actual converging lens array is used by matching the object distance or the image plane distance with a predetermined value.

  Furthermore, the ideal or design value of the object distance of the converging lens array and the ideal or design value of the image plane distance are generally equal to each other, but they are probably different due to manufacturing variations. There can be. Also, depending on the characteristics of the emission wavelength or transmission wavelength of the electro-optical panel or the refraction of the layers in the panel, making the object distance equal to the image plane distance may not necessarily lead to an improvement in resolution.

  In the adjustment method of Patent Document 5, even when the camera is focused on the light emitting element that has passed through the converging lens, a process of combining the light emitting panel and the converging lens array with the image carrier is necessary. Due to variations in mounting in this step and manufacturing variations of the alignment jig of the focusing lens array with respect to the image carrier, high resolution is not always obtained.

  Therefore, the present invention provides an adjustment method and a manufacturing method for an image printing apparatus capable of reliably improving the print quality actually obtained by adjusting at least one of the object distance and the image plane distance of the converging lens array. provide.

  An adjustment method of an image printing apparatus according to the present invention includes: an image carrier; a charger that charges the image carrier; and a plurality of electro-optical elements whose light emission characteristics or light transmission characteristics change according to applied electric energy. An arrayed electro-optic panel and a plurality of gradient index lenses that transmit light traveling from the electro-optic panel and can form an erect image with respect to the image on the electro-optic panel on the image carrier are arranged. A converging lens array for forming a latent image on a charged surface of the image carrier so that images obtained by the plurality of gradient index lenses form one continuous image; An adjustment method for an image printing apparatus, comprising: a developing unit that forms a visible image on the image carrier by attaching toner to an image; and a transfer unit that transfers the visible image from the image carrier to another object. The image printing apparatus A step of forming a visible image, a step of displacing at least one of an interval between the converging lens array and the image carrier and an interval between the electro-optical panel and the converging lens array, and a step of forming the visible image. And the step of repeating the displacing step, and the interval between the converging lens array and the image carrier and the electro-optical panel and the converging lens array based on the evaluation of the quality of the visible image obtained in the repeating step. Adjusting at least one of the intervals.

  According to this adjustment method, at least one of the distance between the focusing lens array and the image carrier and the distance between the electro-optic panel and the focusing lens array is adjusted based on the quality of the actually formed visible image. It is possible to improve the accuracy of the printing, and it is possible to reliably improve the print quality actually obtained.

  An image printing apparatus manufacturing method according to the present invention includes an image carrier, a charger for charging the image carrier, and a plurality of electro-optical elements whose light emission characteristics or light transmission characteristics are changed by applied electric energy. An arrayed electro-optic panel and a plurality of gradient index lenses that transmit light traveling from the electro-optic panel and can form an erect image with respect to the image on the electro-optic panel on the image carrier are arranged. A converging lens array for forming a latent image on a charged surface of the image carrier so that images obtained by the plurality of gradient index lenses form one continuous image; A method for manufacturing an image printing apparatus, comprising: a developing unit that forms a visible image on the image carrier by attaching toner to an image; and a transfer unit that transfers the visible image from the image carrier to another object. And at least the visible A step of assembling the image printing apparatus so that printing is possible, a step of forming a visible image by the image printing apparatus, a distance between the focusing lens array and the image carrier, and the electro-optical panel and the focusing lens. Based on the evaluation of the quality of the visible image obtained in the step of displacing at least one of the intervals of the array, the step of forming the visible image, the step of repeating the displacement step, and the step of repeating, the converging lens Adjusting at least one of an interval between the array and the image carrier and an interval between the electro-optic panel and the converging lens array.

  According to this manufacturing method, at least one of the distance between the focusing lens array and the image carrier and the distance between the electro-optic panel and the focusing lens array is adjusted based on the quality of the actually formed visible image. It is possible to improve the accuracy of the printing, and it is possible to reliably improve the print quality actually obtained.

  Another method of manufacturing an image printing apparatus according to the present invention includes an image carrier, a charger for charging the image carrier, and a plurality of electro-optics whose light emission characteristics or light transmission characteristics are changed by applied electric energy. An electro-optical panel in which elements are arranged, and a plurality of gradient index lenses that transmit light traveling from the electro-optical panel and can form an upright image with respect to the image on the electro-optical panel on the image carrier A converging lens array that forms a latent image on a charged surface of the image carrier so that images obtained by the plurality of gradient index lenses form one continuous image; A method of manufacturing an image printing apparatus, comprising: a developing unit that forms a visible image on the image carrier by attaching toner to the latent image; and a transfer unit that transfers the visible image from the image carrier to another object. The image printing Disposing the electro-optical panel and the converging lens array in a second image printing apparatus comprising a second image carrier of the same type as the device, a second developing device, and a second transfer device; A step of forming a visible image by the image printing apparatus, and a step of displacing at least one of a distance between the converging lens array and the second image carrier and a distance between the electro-optic panel and the converging lens array. A step of repeating the step of forming the visible image and the step of displacing, and an interval between the converging lens array and the second image carrier based on the quality of the visible image obtained in the step of repeating, and Adjusting at least one of a distance between the electro-optical panel and the converging lens array; and printing the image so as to maintain a distance between the electro-optical panel and the converging lens array. And a step of placing the electro-optical panel and the converging lens array location.

  The “manufacturing method” using the second image printing apparatus may be a method for initial manufacture of an image printing apparatus to be manufactured, or a repair method after manufacturing, that is, a reproduction method. According to this manufacturing method, the distance between the converging lens array and the second image carrier and the electrooptics are determined based on the quality of the visible image actually formed by the second image printing apparatus, that is, the adjustment image printing apparatus. Adjust at least one of the distance between the panel and the converging lens array. Thereafter, the electro-optical panel and the focusing lens array are arranged on the image printing apparatus to be manufactured. Since the second image printing apparatus is the same type as the image printing apparatus to be manufactured, the position of the second image carrier in the second image printing apparatus is the position of the image carrier in the image printing apparatus to be manufactured. When the distance between the focusing lens array and the second image carrier is adjusted by the second image printing apparatus, the focusing lens array and the image carrier of the manufacturing image printing apparatus are adjusted. The interval is also a preferable state. Further, in the step of arranging the electro-optical panel and the converging lens array in the image printing apparatus to be manufactured, the distance between the electro-optical panel and the converging lens array is maintained, so that the second image printing apparatus and the electro-optical panel are focused. When the distance between the converging lens arrays is adjusted, the distance between the electro-optical panel and the converging lens array is preferable in the image printing apparatus to be manufactured. Therefore, the accuracy of adjustment can be increased, and the print quality actually obtained can be improved with certainty.

  Hereinafter, various embodiments according to the present invention will be described with reference to the accompanying drawings. In these drawings, the ratio of dimensions of each part is appropriately changed from the actual one.

<First Embodiment>
FIG. 1 is a front view showing an outline of an image printing apparatus 1 according to a first embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along the line II-II in FIG. The image printing apparatus 1 illustrated in the figure uses an electrophotographic system and has an image carrier (for example, a photosensitive drum 110 as shown in FIG. 2). The photosensitive drum 110 rotates around a shaft 12 supported by a bearing 13 fixed to the housing of the image printing apparatus.

  The image printing apparatus 1 also includes a light-emitting panel (electro-optical panel) 10 as a line-type optical head for writing a latent image on the photosensitive drum 110, and a converging lens array 40 superimposed on the light-emitting panel 20. . In the light emitting panel 10, a plurality of organic EL elements (electro-optical elements) are arranged on the same plane. The converging lens array 40 is disposed between the light emitting panel 10 provided with the EL element array and the photosensitive drum 110. The light from the organic EL element array of the light emitting panel 10 passes through the plurality of gradient index lenses of the converging lens array 40, reaches the photosensitive drum 110, and is a surface of the photosensitive drum 110 charged by the charger. To form a latent image.

  Although not shown in FIG. 1, as will be described later in the column of the overall configuration of the image printing apparatus, the image printing apparatus 1 is provided with various components for realizing electrophotographic printing. These components include a charger that charges the photosensitive drum 110 and a toner that adheres to a latent image formed by light emitted from the light emitting panel 10 and transmitted through the converging lens array 40, thereby causing the photosensitive drum 110 to adhere to the photosensitive drum 110. There are a developing device for forming a visible image, a transfer device for transferring the visible image from the photosensitive drum 110 to another object such as a paper sheet or an intermediate transfer belt, and a fixing device for fixing the visible image on the paper sheet.

  As shown in FIG. 3, the converging lens array 40 includes a plurality of gradient index lenses 42. Each of the gradient index lenses 42 is a graded index optical fiber formed such that the refractive index at the central axis, that is, the optical axis is low, and the refractive index increases as the distance from the central axis increases. The erecting image with respect to the image on the light emitting panel 10 can be formed on the photosensitive drum 110 by transmitting the light to be transmitted. The images obtained by the plurality of gradient index lenses 42 constitute one continuous image on the photosensitive drum 110. A specific example of the converging lens array 40 is, for example, SLA (Selfoc Lens Array) available from Nippon Sheet Glass Co., Ltd.

  FIG. 4 is a plan view showing the converging lens array 40 and the light emitting panel 10 in this image printing apparatus. As shown in FIG. 4, the gradient index lenses 42 are arranged in two rows and a staggered pattern, and are fixed to the housing of the converging lens array 40. These gradient index lenses 42 overlap the region of the light emitting panel 10 where the EL elements are provided. The arrangement pattern of the gradient index lens 42 is not limited to the illustrated form, and may be a single row or three or more rows, or may be arranged in another appropriate pattern.

  As shown in FIGS. 1 and 2, the converging lens array 40 is supported by the lens array support 44 in a state of being surrounded by the lens array support 44. The light emitting panel 10 is fixed to the bottom of the frame 22. Although omitted in FIG. 1, the frame 22 has side walls extending from the bottom toward the photosensitive drum 110. The converging lens array 40 is sandwiched between the lens array support 44 and the side wall of the light emitting panel 10, and external light is prevented from entering the optical path from the light emitting panel 10 to the converging lens array 40. .

  The optical dimensions in designing such a converging lens array 40 include a conjugate distance TC (object-image plane distance), an object distance L0, and an image plane distance L1. The object distance L0 is the distance between the light incident surface of the converging lens array 40 and the light emitting panel 10 (more precisely, the light emitting position of the light emitting panel 10), and the image plane distance L1 is the distance of the converging lens array 40. This is the distance between the light exit surface and the photosensitive surface of the photosensitive drum 110. The conjugate distance TC is the distance between the light emitting panel 10 (more precisely, the light emitting position of the light emitting panel 10) and the photosensitive surface of the photosensitive drum 110.

The relationship between ideal design values of these optical dimensions is expressed by using the length Z of the converging lens array, as shown in equations (1) and (2).
TC = L0 + Z + L1. . . (1)
L0 = L1. . . (2)

  These optical dimensions TC, L0, and L1 are determined by design, and the image plane distance L1 and the object distance L0 are equal in design. However, since there are manufacturing variations in the converging lens array, this embodiment is provided with an adjusting mechanism for adjusting the object distance L0 and an adjusting mechanism for adjusting the image plane distance L1 for each individual converging lens array. ing. As these adjusting mechanisms, adjusting screws 52 and 54 are used in this embodiment. However, other known mechanisms such as gears and cams may be used instead of screws. These adjusting screws 52 and 54 are provided in the vicinity of the bearings 13 at both ends of the photosensitive drum 110.

  A first adjustment screw 52 as an adjustment mechanism for the image plane distance L1 is fitted to a female screw formed on the lens array support 44. The front end surface of the first adjusting screw 52 is formed as a curved surface such as a part of a sphere, and this surface contacts the abutting plate 14 fixed to the bearing 13. Although not shown, the lens array support 44 is pressed against the photosensitive drum 110 by a pressing member formed of a spring or other suitable elastic body, whereby the spherical tip of the first adjustment screw 52 is pressed. The surface always contacts the abutting plate 14. Accordingly, when the first adjustment screw 52 is rotated, the photosensitive drum 110 moves relative to the converging lens array 40, and the image plane distance L1 is displaced.

  A second adjustment screw 54 as an adjustment mechanism for the object distance L0 is fitted to a female screw formed on the frame 22. One end surface of the second adjustment screw 52 is also formed as a curved surface such as a part of a sphere, and this surface is in contact with the abutting plate 46 fixed to the lens array support 44. Although not shown, the frame 22 to which the light emitting panel 10 is fixed is also pressed against the converging lens array 40 side by a pressing member formed of a spring or other appropriate elastic body. The spherical tip surface of the adjusting screw 54 is always in contact with the abutting plate 46. Accordingly, when the second adjustment screw 54 is rotated, the converging lens array 40 is moved relative to the light emitting panel 10, and the object distance L0 is displaced.

  Next, an adjustment method for the image printing apparatus according to the first embodiment of the present invention will be described. First, the adjusting screws 52 and 54 are rotated so that the rotation axis of the photosensitive drum 110, the converging lens array 40, and the light emitting panel 10 are parallel to each other.

  Next, a visible image is actually formed. Specifically, the print evaluation patterns P1 to P9 shown in FIG. 5 are printed on a sheet such as paper. Each of the nine print evaluation patterns P1 to P9 is a bar having a gradation different from the other patterns and having a width of several mm. The print evaluation pattern P1 is not white and is the brightest visible image among the print evaluation patterns P1 to P9. The printing evaluation pattern P9 is the darkest visible image among the printing evaluation patterns P1 to P9, and the printing evaluation pattern P5 is a visible image having an intermediate brightness among the printing evaluation patterns P1 to P9. Although not shown, the print evaluation patterns P2 to P4 have a brightness between the print evaluation patterns P1 and P5, and the print evaluation patterns P6 to P8 have a brightness between the print evaluation patterns P5 and P9.

  FIG. 6 shows print evaluation pattern blocks constituting the print evaluation patterns P1 to P9 shown in FIG. Each of the print evaluation pattern blocks Pb1 to Pb9 in FIG. 6 corresponds to a set of nine organic EL elements. The organic EL element that emits light from the light-emitting panel 10 forms a latent image dot on the photosensitive drum 110, and toner adheres to the dot to form a visible image dot. Accordingly, since the number of dots of the visible image to be printed varies depending on the number of the organic EL elements that emit light among the nine organic EL elements, the nine print evaluation pattern blocks Pb1 to Pb9 illustrated are realized. Each of the print evaluation patterns P1 to P9 in FIG. 5 is a set of the same print evaluation pattern blocks. For example, the brightest print evaluation pattern P1 is a set of many print evaluation pattern blocks Pb1, and the darkest print evaluation pattern P9 is a set of many print evaluation pattern blocks Pb9.

  In the example of FIG. 6, nine printing evaluation pattern blocks Pb1 to Pb9 are obtained by nine organic EL elements having a vertical length of 3 and a horizontal width of 3, so that a 9-tone printing evaluation pattern is realized. However, the print evaluation pattern block may be obtained by another number of organic EL elements. For example, if a print evaluation pattern block obtained by 16 organic EL elements having a length of 4 and a width of 4 is used, a 16-tone print evaluation pattern can be realized.

  Next, the density of each of the actually printed printing evaluation patterns P1 to P9 is measured, and the measurement result is plotted in the graph illustrated in FIG. 7 from the measurement result. For example, it is assumed that the line B in FIG. 7 shows the measurement result at this time.

  Further, at least one of the image plane distance L1 (the interval between the focusing lens array 40 and the photosensitive drum 110) and the object distance L0 (the interval between the electro-optical panel and the focusing lens array) is displaced by a certain amount. As is clear from the above description, in order to displace the image plane distance L1 by a certain amount, all the first adjustment screws 52 may be rotated at a certain rotation angle, and the object distance L0 is displaced by a certain amount. All the second adjustment screws 54 may be rotated at a constant rotation angle. The operation of the adjusting mechanism, that is, the rotation of the adjusting screws 52 and 54 may be performed manually or by a motor (not shown).

  Thereafter, in the same manner as described above, the print evaluation patterns P1 to P9 are printed on another sheet, the densities of the print evaluation patterns P1 to P9 printed this time are measured, and the graph illustrated in FIG. Plot the measurement results. For example, it is assumed that the line C in FIG. 7 shows the measurement result at this time. Further, at least one of the image plane distance L1 and the object distance L0 is displaced by a certain amount, the printing evaluation patterns P1 to P9 are printed on another sheet, and the density of each of the printing evaluation patterns P1 to P9 printed this time is measured. It repeats plotting a measurement result in the graph illustrated in FIG. 7 from a measurement result.

In FIG. 7, line A indicates the ideal print density for the print evaluation patterns P1 to P9. Since each of the print evaluation patterns P1 to P9 has a number of visible dots proportional to the subscript of the code (for example, 5 for P5), the ideal print density indicated by the line A is also the print evaluation pattern P1 to P9. It is proportional to the subscript of P9. However, in actual printing, as shown in FIG. 8, if at least one of the image plane distance L1 and the object distance L0 is inappropriate, each dot of the latent image on the photosensitive drum 110 and finally the final image due to the focus shift. The area of each dot of the visible image obtained in (1) increases. Therefore, the measurement results of the densities of the actually printed printing evaluation patterns P1 to P9 are higher than the ideal density indicated by the line A as indicated by the lines B and C.

  As is clear from the above, the measurement result corresponding to the line closest to the ideal line A among the above-mentioned multiple print density measurement results is more preferable. For example, the measurement result of line C is better than the measurement result of line B. From this viewpoint, the print density measurement result is evaluated, and the optimum image plane distance L1 and object distance L0 are selected. However, since the distances L1 and L0 do not need to be measured, instead of selecting the distances L1 and L0, the angle at which the adjusting screws 52 and 54 should be rotated may be selected. Based on this selection, at least one of the adjustment screws 52 and 54 is rotated to adjust at least one of the image plane distance L1 and the object distance L0. After the adjustment, the image bearing distance L1 and the object distance L0 may be maintained by fixing the bearing 13, the lens array support 44 and the frame 22 by a fixing mechanism different from the adjusting screws 52 and 54. .

  In this embodiment, print evaluation patterns P1 to P9 illustrated in FIG. 5 are used as indexes for evaluating the quality of the visible image, but other indexes may be used. For example, the quality of the visible image may be evaluated based on the size of the visible image dot obtained by causing only one or several organic EL elements in the light emitting panel 10 to emit light. As described above, in actual printing, if at least one of the image plane distance L1 and the object distance L0 is inappropriate, each dot of the latent image on the photosensitive drum 110 and eventually a visible image obtained by the focus shift. The area of each dot increases. For example, in FIG. 9, dots D1 and D2 are visible image dots printed on different sheets at different image plane distances L1 (or object distances L0) (FIG. 9 shows the dots enlarged). . The dot D1 having a smaller diameter than the dot D2 is preferable. From this viewpoint, the dot size measurement result of the visible image is evaluated, and the optimum image plane distance L1 and object distance L0 are selected. Based on this selection, at least one of the adjustment screws 52 and 54 is rotated to adjust at least one of the image plane distance L1 and the object distance L0.

  As described above, according to the adjustment method according to this embodiment, based on the quality of the actually formed visible image, the distance between the focusing lens array and the image carrier and the electro-optical panel and the focusing lens array Since at least one of the intervals is adjusted, it is possible to improve the accuracy of the adjustment for each individual converging lens array 40, and it is possible to surely improve the actually obtained print quality.

  The adjustment method of the image printing apparatus 1 in a state where the image printing apparatus 1 is completed has been described above. However, this adjustment method is used at the stage of the manufacturing process (however, at least a visible image can be formed on a sheet of paper). The image printing apparatus 1 may be manufactured by using it. In other words, at least after the step of assembling the image printing apparatus 1 so that a visible image can be printed, this adjustment method is performed, and the distance between the converging lens array and the image carrier and the electro-optical panel and the converging lens array are adjusted. At least one of the intervals may be adjusted, and the subsequent steps of manufacturing the image printing apparatus 1 may be advanced.

<Second Embodiment>
Next, a second embodiment of the present invention will be described. The second embodiment relates to a method for manufacturing an image printing apparatus. In this manufacturing method, an image printing apparatus different from the image printing apparatus to be manufactured is used to optimize at least one of the image plane distance L1 and the object distance L0 related to the converging lens array 40 and the light emitting panel 10, and then manufactured. The converging lens array 40 and the light emitting panel 10 are incorporated into the target image printing apparatus. The image printing apparatus to be manufactured according to the second embodiment has the same configuration as the image forming apparatus 1 of the first embodiment described with reference to FIGS.

  In the method for manufacturing an image printing apparatus according to the second embodiment, as shown in FIG. 10A, first, a second image printing apparatus 1A of the same type as the image printing apparatus 1 to be manufactured is prepared. The second image printing apparatus 1A is used for adjusting the image printing apparatus 1 to be manufactured. For this purpose, the second image printing apparatus 1A is not provided with the converging lens array 40 and the light emitting panel 10 dedicated to the second image printing apparatus 1A. However, the second image printing apparatus 1A is provided with various components for realizing electrophotographic printing, for example, the second photosensitive drum 110A. In addition to the second photoconductor drum 110A, components for realizing electrophotographic printing are not shown, but are emitted from the second charger and the light emitting panel 10 for charging the photoconductor drum 110A and converged. A second developing unit for forming a visible image on the photosensitive drum 110A by attaching toner to the latent image formed by the light transmitted through the photosensitive lens array 40, and the visible image from the photosensitive drum 110A to another object, for example, There is a second transfer device for transferring to a paper sheet or an intermediate transfer belt, and a second fixing device for fixing a visible image on the paper sheet.

  Further, the light emitting panel 10 supported by the frame 22, the converging lens array 40 supported by the lens array support 44, and the adjusting screws 52 and 54 are prepared. As shown in FIG. 2 in the image printing apparatus 1A. The positions where these are to be arranged correspond to these arrangement positions in the image printing apparatus 1 to be manufactured. Accordingly, the first adjustment screw 52 is fitted into a female screw formed on the lens array support 44. The front end surface of the first adjustment screw 52 is in contact with the abutting plate 14A fixed to the bearing 13A of the second photosensitive drum 110A. Although not shown, the lens array support 44 is pressed against the photosensitive drum 110 </ b> A by a pressing member formed of a spring or other appropriate elastic body, whereby the spherical tip surface of the first adjustment screw 52 is It always contacts the butting plate 14A. Therefore, if the first adjustment screw 52 is rotated, the photosensitive drum 110A moves relative to the converging lens array 40, and the image plane distance L11 (of the converging lens array 40 of the second photosensitive drum 110A) is moved. The distance between the light emitting surface and the photosensitive surface of the photosensitive drum 110A) is displaced.

  The second adjustment screw 54 is fitted to a female screw formed on the frame 22. The distal end surface of the second adjustment screw 52 contacts a butting plate 46 fixed to the lens array support 44. Although not shown, the frame 22 to which the light emitting panel 10 is fixed is also pressed against the converging lens array 40 side by a pressing member formed of a spring or other appropriate elastic body. The spherical tip surface of the adjusting screw 54 is always in contact with the abutting plate 46. Accordingly, when the second adjustment screw 54 is rotated, the converging lens array 40 is moved relative to the light emitting panel 10, and the object distance L0 is displaced. As described above with respect to the first embodiment, the adjustment mechanism that adjusts the object distance L0 and the adjustment mechanism that adjusts the image plane distance L11 are not limited to the adjustment screws 52 and 54, but are other known ones such as gears and cams. A mechanism may be used.

  As shown in FIG. 10B, with the adjusting screws 52 and 54 set, the rotational axis of the second photosensitive drum 110A, the converging lens array 40, and the light emitting panel 10 are parallel to each other. Then, the adjusting screws 52 and 54 are rotated.

  Next, in the same manner as the adjustment method described above with respect to the first embodiment, a visible image is actually formed, that is, printed. The visible image to be printed may be the print evaluation patterns P1 to P9 illustrated in FIG. 5 or the dots shown in FIG. Then, a measurement object such as the density or dot diameter of each of the actually printed printing evaluation patterns P1 to P9 is measured.

  Thereafter, at least one of the image plane distance L11 and the object distance L0 is displaced by a certain amount, and the visible image is printed on another sheet, and the measurement object of the visible image printed this time is repeatedly measured. After this repetition, the measurement result is evaluated and the optimum image plane distance L11 and object distance L0 are selected. However, since the distances L11 and L0 do not need to be measured, instead of selecting the distances L11 and L0, the angle at which the adjustment screws 52 and 54 should be rotated may be selected. Based on this selection, at least one of the adjustment screws 52 and 54 is rotated to adjust at least one of the image plane distance L11 and the object distance L0.

  Furthermore, the light emitting panel 10 and the converging lens array 40 are transferred to the image printing apparatus 1 to be manufactured so as to maintain the distance between the light emitting panel 10 and the converging lens array 40 (object distance L0). That is, the pressing member that presses the lens array support 44 to the second photosensitive drum 110A side and the pressing member that presses the frame 22 to the converging lens array 40 side are released, and the optical device having the light emitting panel 10 and the converging lens array 40 is released. The member set 60 is removed from the second image printing apparatus 1A shown in FIG. 10B, and the state shown in FIG. Further, the optical member set 60 is disposed in the image printing apparatus 1 to be manufactured as shown in FIG. In addition to the light emitting panel 10 and the converging lens array 40, the optical member set 60 includes a lens array support 44 that supports the converging lens array 40 by fixing the frame 22 and the abutting plate 46 that support the light emitting panel 10. The first adjusting screw 52 fitted to the lens array support 44 and the second adjusting screw 54 fitted to the frame 22 are provided. While the optical member set 60 is moved, the adjusting screws 52 and 54 are not rotated.

  While the optical member set 60 is moved, as shown in FIG. 10A, the converging lens array 40 and the light emitting panel 10 (more precisely, the butting plate 46 and the second adjustment screw 54) are separated from each other. Good. If the second adjustment screw 54 is not rotated, the protruding length of the second adjustment screw 54 from the light emitting panel 10 is maintained in the state of the second photosensitive drum 110A. Therefore, even if the second adjustment screw 54 is temporarily separated from the abutting plate 46, the abutting plate is attached to the tip of the second adjustment screw 54 that serves as a reference for the object distance L 0 in the image printing apparatus 1 to be manufactured. If the light-emitting panel 10 and the converging lens array 40 are incorporated so that 46 is in contact, the object distance L0 realized by the second image printing apparatus 1A is also realized by the image printing apparatus 1. As a result, during the movement of the optical member set 60, the object distance L0 is maintained by the second adjustment screw 54.

  When the optical member set 60 is thus arranged in the image printing apparatus 1 to be manufactured, the distance (image plane distance L1) between the photosensitive drum 110 and the converging lens array 40 in the image printing apparatus 1 is the second image. The distance (image plane distance L11) between the second photosensitive drum 110A and the converging lens array 40 in the printing apparatus 1A is substantially the same. Since the second image printing apparatus 1A is the same type as the image printing apparatus 1 to be manufactured, the positions of the second photosensitive drum 110A and the butting plate 14A in the second image printing apparatus 1A are the images to be manufactured. This is because the positions of the photosensitive drum 110 and the butting plate 14 in the printing apparatus 1 are substantially the same. In the image printing apparatus 1 to be manufactured, if the converging lens array 40 is incorporated so that the abutting plate 14 comes into contact with the tip of the first adjustment screw 52 serving as a reference for the image plane distance, the second image printing is performed. An image plane distance L1 substantially equal to the image plane distance L11 realized by the apparatus 1A is realized by the image printing apparatus 1.

  For example, the image plane distance L11 in the second image printing apparatus 1A may differ from the image plane distance L1 in the image printing apparatus 1 to be manufactured due to a manufacturing error of the bearings 13 and 13A. Nevertheless, the focusing lens array is transferred from another type of adjusting device (for example, a device that adjusts the position of the focusing lens array so that the camera is focused on the light emitting element as in Patent Document 5) to the image printing device to be manufactured. Compared to the technique, in this embodiment, the converging lens array 40 is moved from the second image printing apparatus 1A for adjustment of the same type as the image printing apparatus 1 to be manufactured to the image printing apparatus 1, and therefore the image plane distance L11. , L1 should be quite small.

  After the optical member set 60 is assembled in the image printing apparatus 1 in this way, the bearing 13, the lens array support 44 and the frame 22 are fixed by a fixing mechanism different from the adjusting screws 52 and 54, and the image plane distance is fixed. L1 and the object distance L0 may be maintained.

  As described above, according to the manufacturing method according to this embodiment, the converging lens array 40 is based on the quality of the visible image actually formed by the second image printing apparatus, that is, the adjustment image printing apparatus 1A. And at least one of the interval between the second photosensitive drum 110A and the interval between the light emitting panel 10 and the converging lens array 40 is adjusted. Thereafter, the light emitting panel 10 and the converging lens array 40 are arranged in the image printing apparatus 1 to be manufactured. Since the second image printing apparatus 1A is the same type as the image printing apparatus 1 to be manufactured, the position of the second photosensitive drum 110A in the second image printing apparatus 1A is the position of the image printing apparatus 1 to be manufactured. When the distance between the converging lens array 40 and the second photosensitive drum 110A is adjusted by the second image printing apparatus 1A, the position of the photosensitive drum 110 is almost the same as the position of the photosensitive drum 110. The distance between the converging lens array 40 and the photosensitive drum 110 is also a preferable state. Further, in the step of disposing the light emitting panel 10 and the converging lens array 40 in the image printing apparatus 1 to be manufactured, the second adjustment screw 54 maintains the distance between the light emitting panel 10 and the converging lens array 40. When the distance between the light emitting panel 10 and the converging lens array 40 is adjusted by the image printing apparatus 1A, the distance between the light emitting panel 10 and the converging lens array 40 is preferable in the image printing apparatus 1 to be manufactured. Therefore, the accuracy of adjustment can be increased, and the print quality actually obtained can be improved with certainty.

  The manufacturing method according to this embodiment may be a method for the initial manufacturing of the image printing apparatus 1 or a repair method after manufacturing, that is, a reproduction method.

<Overall configuration of image printing apparatus>
As described above, the image printing apparatus 1 according to the present invention can be used as a line-type optical head for writing a latent image on an image carrier in an image printing apparatus using an electrophotographic system. Examples of the image printing apparatus include a printer, a printing part of a copying machine, and a printing part of a facsimile.

  FIG. 15 is a longitudinal sectional view showing an example of the overall configuration of the image printing apparatus 1. This image printing apparatus is a tandem type full-color image printing apparatus using a belt intermediate transfer body system.

  In this image printing apparatus, four organic EL array exposure heads 10K, 10C, 10M, and 10Y having the same configuration are replaced with four photosensitive drums (image carriers) 110K, 110C, 110M, and 110Y having the same configuration. The exposure positions are respectively arranged. The organic EL array exposure heads 10K, 10C, 10M, and 10Y are any of the image printing apparatuses 10, 10A, and 10B described above.

  As shown in FIG. 15, this image printing apparatus is provided with a driving roller 121 and a driven roller 122, and an endless intermediate transfer belt 120 is wound around these rollers 121 and 122, as indicated by arrows. Thus, the periphery of the rollers 121 and 122 is rotated. Although not shown, tension applying means such as a tension roller that applies tension to the intermediate transfer belt 120 may be provided.

  Around the intermediate transfer belt 120, photosensitive drums 110K, 110C, 110M, and 110Y having photosensitive layers on four outer peripheral surfaces are arranged at predetermined intervals. The subscripts K, C, M, and Y mean that they are used to form black, cyan, magenta, and yellow visible images, respectively. The same applies to other members. The photosensitive drums 110K, 110C, 110M, and 110Y are rotationally driven in synchronization with the driving of the intermediate transfer belt 120.

  Around each photosensitive drum 110 (K, C, M, Y), a corona charger 111 (K, C, M, Y), an organic EL array exposure head 10 (K, C, M, Y), and Developers 114 (K, C, M, Y) are disposed. The corona charger 111 (K, C, M, Y) uniformly charges the outer peripheral surface of the corresponding photosensitive drum 110 (K, C, M, Y). The organic EL array exposure head 10 (K, C, M, Y) is the light emitting panel 10 described above, and writes an electrostatic latent image on the charged outer peripheral surface of the photosensitive drum. A converging lens array 40 is provided between the organic EL array exposure head 10 (K, C, M, Y) and the photosensitive drum 110 (K, C, M, Y). The illustration of the array 40 is omitted. In each organic EL array exposure head 10 (K, C, M, Y), the arrangement direction of the plurality of EL elements is along the bus (main scanning direction) of the photosensitive drum 110 (K, C, M, Y). Installed. The electrostatic latent image is written by irradiating the photosensitive drum with light from a plurality of EL elements. The developing device 114 (K, C, M, Y) forms a visible image, that is, a visible image on the photosensitive drum by attaching toner as a developer to the electrostatic latent image.

  The black, cyan, magenta, and yellow developed images formed by the four-color single-color image forming station are sequentially transferred onto the intermediate transfer belt 120 to be superimposed on the intermediate transfer belt 120. As a result, a full-color visible image is obtained. Four primary transfer corotrons (transfer devices) 112 (K, C, M, Y) are arranged inside the intermediate transfer belt 120. The primary transfer corotron 112 (K, C, M, Y) is disposed in the vicinity of the photosensitive drum 110 (K, C, M, Y), and the photosensitive drum 110 (K, C, M, Y). The electrostatic image is electrostatically attracted from the toner image to transfer the visible image to the intermediate transfer belt 120 passing between the photosensitive drum and the primary transfer corotron.

  A sheet 102 as an object on which an image is to be finally formed is fed one by one from the sheet feeding cassette 101 by the pickup roller 103, and between the intermediate transfer belt 120 and the secondary transfer roller 126 in contact with the driving roller 121. Sent to the nip. The full-color visible image on the intermediate transfer belt 120 is secondarily transferred to one side of the sheet 102 by the secondary transfer roller 126 and fixed on the sheet 102 through the fixing roller pair 127 as a fixing unit. . Thereafter, the sheet 102 is discharged onto a paper discharge cassette formed in the upper part of the apparatus by a paper discharge roller pair 128.

  For this type of image printing apparatus, the above adjustment method or manufacturing method is used for each of the set of the photosensitive drum 110 (K, C, M, Y) and the organic EL array exposure head 10 (K, C, M, Y). In the method, the printed visible image is evaluated, and at least one of the image plane distance L1 and the object distance L0 is adjusted.

Next, another embodiment of the image printing apparatus according to the present invention will be described.
FIG. 16 is a longitudinal sectional view of another example of the overall configuration of the image printing apparatus 1. This image printing apparatus is a rotary development type full-color image printing apparatus using a belt intermediate transfer body system. In the image printing apparatus shown in FIG. 16, a corona charger 168, a rotary developing unit 161, an organic EL array exposure head 167, and an intermediate transfer belt 169 are provided around a photosensitive drum (image carrier) 165. Yes.

  The corona charger 168 uniformly charges the outer peripheral surface of the photosensitive drum 165. The organic EL array exposure head 167 writes an electrostatic latent image on the charged outer peripheral surface of the photosensitive drum 165. The organic EL array exposure head 167 is the light-emitting panel 10 described above, and is installed so that the arrangement direction of the plurality of EL elements is along the bus line (main scanning direction) of the photosensitive drum 165. The electrostatic latent image is written by irradiating the photosensitive drum with light from the plurality of EL elements. A converging lens array 40 is provided between the organic EL array exposure head 167 and the photosensitive drum 165, but the converging lens array 40 is not shown in FIG.

  The developing unit 161 is a drum in which four developing units 163Y, 163C, 163M, and 163K are arranged at an angular interval of 90 °, and can rotate counterclockwise about the shaft 161a. The developing units 163Y, 163C, 163M, and 163K supply yellow, cyan, magenta, and black toners to the photosensitive drum 165, respectively, and attach the toner as a developer to the electrostatic latent image, thereby the photosensitive drum 165. A visible image, that is, a visible image is formed.

  The endless intermediate transfer belt 169 is wound around a driving roller 170a, a driven roller 170b, a primary transfer roller 166, and a tension roller, and is rotated around these rollers in a direction indicated by an arrow. The primary transfer roller 166 transfers the visible image to the intermediate transfer belt 169 that passes between the photosensitive drum and the primary transfer roller 166 by electrostatically attracting the visible image from the photosensitive drum 165.

  Specifically, in the first rotation of the photosensitive drum 165, an electrostatic latent image for a yellow (Y) image is written by the exposure head 167, and a developed image of the same color is formed by the developing unit 163Y. The image is transferred to the transfer belt 169. Further, in the next rotation, an electrostatic latent image for a cyan (C) image is written by the exposure head 167, and a developed image of the same color is formed by the developing device 163C. The intermediate transfer is performed so as to overlap the yellow developed image. Transferred to the belt 169. Then, during the four rotations of the photosensitive drum 9, the yellow, cyan, magenta, and black visible images are sequentially superimposed on the intermediate transfer belt 169. As a result, a full-color visible image is formed on the transfer belt 169. It is formed. When images are finally formed on both sides of a sheet as an object on which an image is to be formed, the same color images of the front and back surfaces are transferred to the intermediate transfer belt 169, and then the front and back surfaces are transferred to the intermediate transfer belt 169. A full-color visible image is obtained on the intermediate transfer belt 169 by transferring the visible image of the next color.

  The image printing apparatus is provided with a sheet conveyance path 174 through which a sheet is passed. The sheets are picked up one by one from the paper feed cassette 178 by the pick-up roller 179, advanced through the sheet transport path 174 by the transport roller, and between the intermediate transfer belt 169 and the secondary transfer roller 171 in contact with the drive roller 170a. Pass through the nip. The secondary transfer roller 171 transfers the developed image to one side of the sheet by electrostatically attracting a full-color developed image from the intermediate transfer belt 169 collectively. The secondary transfer roller 171 can be moved closer to and away from the intermediate transfer belt 169 by a clutch (not shown). The secondary transfer roller 171 is brought into contact with the intermediate transfer belt 169 when a full-color visible image is transferred onto the sheet, and is separated from the secondary transfer roller 171 while the visible image is superimposed on the intermediate transfer belt 169.

  The sheet on which the image has been transferred as described above is conveyed to the fixing device 172 and is passed between the heating roller 172a and the pressure roller 172b of the fixing device 172, whereby the visible image on the sheet is fixed. The sheet after the fixing process is drawn into the discharge roller pair 176 and proceeds in the direction of arrow F. In the case of double-sided printing, after most of the sheet passes through the paper discharge roller pair 176, the paper discharge roller pair 176 is rotated in the reverse direction and introduced into the double-sided printing conveyance path 175 as indicated by an arrow G. The Then, the visible image is transferred to the other surface of the sheet by the secondary transfer roller 171, the fixing process is performed again by the fixing device 172, and then the sheet is discharged by the discharge roller pair 176.

  For this type of image printing apparatus, with respect to the photosensitive drum 165 and the exposure head 167, the above-described adjustment method or manufacturing method evaluates the printed visible image and adjusts at least one of the image plane distance L1 and the object distance L0. To do. The evaluation of the visible image may be an evaluation of a printed image of one color or an evaluation of a printed image of a plurality of colors.

  Although the overall configuration of the image printing apparatus 1 has been exemplified above, the image printing apparatus 1 according to the present invention can be applied to other electrophotographic image printing apparatuses. Within the scope of the invention. For example, an image printing apparatus that directly transfers a visible image from a photosensitive drum to a sheet without using an intermediate transfer belt, or an image printing apparatus that forms a monochrome image may be used. An image printing apparatus using a belt may be used.

<Modification>
In the above electro-optical device, the converging lens array 40 is attached to the light emitting panel having the light emitting elements, but the converging lens array may be attached to the light valve panel having a large number of light valve pixels. The light valve pixel is a pixel whose light transmittance is changed by applied electric energy, and includes, for example, a liquid crystal pixel, an electrochemical display pixel, an electrophoretic display pixel, and a dispersed particle orientation display pixel. These all adjust the amount of light transmitted from a separate light source. Instead of the light-emitting panel 10, a light valve panel such as a liquid crystal panel can be attached to the microlens array so that light from separate light sources is transmitted through the light valve panel and the converging lens array. .

1 is a front view showing an outline of an image printing apparatus according to a first embodiment of the present invention. It is the II-II sectional view taken on the line of FIG. It is a perspective view which shows the outline of the converging lens array used with the image printing apparatus of FIG. It is a top view which shows the converging lens array and the light emission panel in the image printing apparatus of FIG. It is a figure which shows the printing evaluation pattern which can be used as a printing quality evaluation parameter | index with the adjustment method and manufacturing method of the image printing apparatus which concerns on embodiment of this invention. FIG. 6 shows a print evaluation pattern block constituting the print evaluation pattern shown in FIG. 5. FIG. It is a graph which shows the measurement result of each density | concentration of the printing evaluation pattern actually printed. It is a graph which shows the relationship between the image surface distance or object distance of a converging lens array, and the area of the dot printed. FIG. 4 is an enlarged view of dots printed on a sheet that can be used as an evaluation index of print quality in the adjustment method and the manufacturing method of the image printing apparatus according to the embodiment of the present invention. It is a figure which shows the process of the manufacturing method of the image printing apparatus which concerns on the 2nd Embodiment of this invention. 1 is a longitudinal sectional view showing an example of the overall configuration of an image printing apparatus according to the present invention. It is a longitudinal cross-sectional view which shows another example of the whole structure of the image printing apparatus which concerns on this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Image printing apparatus, 10 Light emission panel (electro-optical panel), 22 frames, 40 Converging lens array, 44 Lens array support body, 110 Photosensitive drum (image carrier), TC Conjugation distance, L0 Object distance, L1, L11 Image plane distance, 52 1st adjustment screw, 54 2nd adjustment screw, 1A 2nd image printing device, 110A 2nd photoconductor drum.

Claims (3)

An image carrier;
A charger for charging the image carrier;
An electro-optical panel in which a plurality of electro-optical elements whose light emission characteristics or light transmission characteristics are changed by given electric energy are arranged;
A plurality of gradient index lenses are arranged so that light traveling from the electro-optic panel can be transmitted and an erect image with respect to the image on the electro-optic panel can be formed on the image carrier. A converging lens array that forms a latent image on a charged surface of the image carrier, such that the image obtained by the lens forms one continuous image;
A developing unit that forms a visible image on the image carrier by attaching toner to the latent image; and
An adjustment method of an image printing apparatus comprising: a transfer device that transfers the visible image from the image carrier to another object,
Forming a visible image by the image printing apparatus;
Displacing at least one of an interval between the converging lens array and the image carrier and an interval between the electro-optic panel and the converging lens array;
Repeating the step of forming the visible image and the step of displacing;
Adjusting at least one of the interval between the converging lens array and the image carrier and the interval between the electro-optic panel and the converging lens array based on the evaluation of the quality of the visible image obtained in the repeating step; A method for adjusting an image printing apparatus including: An image carrier;
A charger for charging the image carrier;
An electro-optical panel in which a plurality of electro-optical elements whose light emission characteristics or light transmission characteristics are changed by given electric energy are arranged;
A plurality of gradient index lenses are arranged so that light traveling from the electro-optic panel can be transmitted and an erect image with respect to the image on the electro-optic panel can be formed on the image carrier. A converging lens array that forms a latent image on a charged surface of the image carrier, such that the image obtained by the lens forms one continuous image;
A developing unit that forms a visible image on the image carrier by attaching toner to the latent image; and
A method for manufacturing an image printing apparatus comprising: a transfer device that transfers the visible image from the image carrier to another object,
Assembling the image printing apparatus so that at least a visible image can be printed;
Forming a visible image by the image printing apparatus;
Displacing at least one of an interval between the converging lens array and the image carrier and an interval between the electro-optic panel and the converging lens array;
Repeating the step of forming the visible image and the step of displacing;
Adjusting at least one of the interval between the converging lens array and the image carrier and the interval between the electro-optic panel and the converging lens array based on the evaluation of the quality of the visible image obtained in the repeating step; A method for manufacturing an image printing apparatus. An image carrier;
A charger for charging the image carrier;
An electro-optical panel in which a plurality of electro-optical elements whose light emission characteristics or light transmission characteristics are changed by given electric energy are arranged;
A plurality of gradient index lenses are arranged so that light traveling from the electro-optic panel can be transmitted and an erect image with respect to the image on the electro-optic panel can be formed on the image carrier. A converging lens array that forms a latent image on a charged surface of the image carrier, such that the image obtained by the lens forms one continuous image;
A developing unit that forms a visible image on the image carrier by attaching toner to the latent image; and
A method for manufacturing an image printing apparatus comprising: a transfer device that transfers the visible image from the image carrier to another object,
Disposing the electro-optical panel and the converging lens array in a second image printing apparatus including a second image carrier of the same type as the image printing apparatus, a second developing unit, and a second transfer unit; ,
Forming a visible image with the second image printing apparatus;
Displacing at least one of an interval between the converging lens array and the second image carrier and an interval between the electro-optical panel and the converging lens array;
Repeating the step of forming the visible image and the step of displacing;
Based on the quality of the visible image obtained in the repeating step, at least one of an interval between the converging lens array and the second image carrier and an interval between the electro-optic panel and the converging lens array is adjusted. Process,
A method of manufacturing an image printing apparatus, comprising: arranging the electro-optical panel and the converging lens array in the image printing apparatus so as to maintain a distance between the electro-optical panel and the converging lens array.

Images