JP2006212844A - Image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce a deterioration and variation in printing quality or the like while reducing running cost of a printer. <P>SOLUTION: A bar-shaped body 7 is a member extending toward a printer head 3 side and a photoreceptor drum 4 side respectively on the basis of a Selfoc (R) lens array 6, wherein the printer head 3 and the photoreceptor drum 4 each independent from the Selfoc (R) lens array 6 are abutted on both ends of the bar-shaped body 7 to simply and accurately position the printer head 3 and the photoreceptor drum 4 to be newly fitted. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a technical field of an image forming apparatus such as a printer, a copy, and a facsimile provided with a Selfoc lens array used to form an electrostatic latent image by exposing a photoreceptor.

  In an image forming apparatus provided with a Selfoc lens array that refracts light emitted from the light emitting portion of the line head and guides it to the photosensitive member, the Selfoc lens and the photosensitive member can be brought close to each other. That is, since the photoconductor can be irradiated with light by the contact optical system, the size of an image forming apparatus such as a printer can be reduced. Such an image forming apparatus often uses a printer head unit configured by incorporating a SELFOC lens array and a line head into a case.

  It is not limited to a printer head unit having a Selfoc lens array. For a printer unit having a line head having a rod lens array, even when the rod lens array is removed from the line head and the rod lens array is cleaned, etc. An adjustment mechanism (for example, refer to Patent Document 1) that can strictly adjust the distance between the line head and the surface to be scanned of the photoreceptor again, or an end surface light emitting unit in which organic EL elements are arranged, and the end surface light emitting unit. An adjustment mechanism (for example, Patent Document 2) that adjusts the relative position of an image carrier on which an electrostatic latent image is carried by light is also disclosed.

  In addition, a technique that can reduce damage to the light emitting surface of the line head during maintenance of the line head is also disclosed (see, for example, Patent Documents 3 and 4).

JP-A-3-253363 JP-A-5-142927 JP-A-5-193186 Japanese Patent Laid-Open No. 5-281895

  However, when the printer head unit is configured by integrating the SELFOC lens array and the line head in the case, the entire printer head unit can be used according to the life of the light emitting cells of the line head. A new Selfoc array is also replaced as a consumable with the printer head unit. In addition, when a photoconductor unit is configured by integrating the SELFOC lens array and the photoconductor, the entire photoconductor unit will be replaced according to the life of the photoconductor as in the case of the printer head unit. A new Selfoc lens array is also replaced as a consumable. The SELFOC lens array is included in an expensive category among components constituting the image forming apparatus, and the usable SELFOC lens array is replaced according to the life of the light emitting cell or the photosensitive member. There is a problem that the running cost of the apparatus is remarkably increased.

  In addition to the variation in external dimensions of lots, the SELFOC lens array has a high-quality electrostatic latent image on the photoconductor unless the distances from the SELFOC lens array to the line head and photoconductor are adjusted accurately. It becomes difficult to form an image. Therefore, when the photosensitive member, the Selfoc lens array, and the line head, which are part of the constituent elements of the image forming apparatus, are separated, these constituent elements each time the photosensitive member or the line head whose characteristics have deteriorated due to the lifetime are replaced. There is a need to accurately adjust the distance between them to maintain image quality. In addition, when the SELFOC lens array is replaced, the variation in the external dimensions of the SELFOC lens array varies from lot to lot, and the distance between these components is adjusted according to the variation in the external dimensions of the SELFOC lens array. Is required. In order to perform such adjustment, an adjustment mechanism composed of a plurality of parts is required separately, which complicates the configuration of the image forming apparatus and causes a problem of adjusting the distance between these components. is there.

  Therefore, the present invention has been made in view of the above-described problems. For example, an increase in cost caused by replacement of a usable Selfoc lens array, and a Selfoc lens array, a line head, and a photoreceptor. An object of the present invention is to provide an image forming apparatus that can reduce the cost required for an adjustment mechanism that accurately adjusts the distance to the image forming apparatus. It is another object of the present invention to provide an image forming apparatus that can suppress deterioration of image quality caused by replacement work of consumables such as a line head or a photoreceptor with a simple configuration.

  In order to solve the above problems, an image forming apparatus according to the present invention includes a housing, a line head including a plurality of light emitting units arranged in a line, and an irradiation destination of light emitted from the plurality of light emitting units. A photosensitive member, a support part for supporting the photosensitive member, and the line head and the photosensitive member so as to be disposed between the photosensitive member, and the light is refracted by refracting the light. A SELFOC lens array that guides light to the photosensitive member, and extends toward the line head side and the photosensitive member side with reference to the SELFOC lens array, and contacts the line head to contact the line head. Positioning means having one end for determining the position of the head and the other end for determining the position of the photoconductor by abutting against the support, and an electrostatic latent image formed on the photoconductor. Image forming means for forming a visible image on a recording medium, the object distance and the image plane distance of the Selfoc lens array are equal, and the distance between the line head and the photoconductor is the cell. The length from the one end to the other end is set to be the conjugate length of the Fock lens array.

  In the image forming apparatus according to the present invention, the housing is a case that houses each component constituting, for example, a printer. The plurality of light emitting units arranged in a line form includes, for example, organic EL elements arranged in a line form. Here, “arranged in a line” includes not only extending in a single line along the line direction in which a plurality of light emitting units are arranged, but also extending in two or more lines, or extending in a staggered pattern. . The line head having the light emitting units arranged in a line shape emits light in a line shape from the light emitting element array sequentially along the line direction in which the light emitting units are arranged. Is possible. Alternatively, line-shaped light can be emitted from the light-emitting element array at the same time or a part thereof.

  The support unit is a member that supports the photoconductor in order to fix the photoconductor to a housing that fixes the photoconductor, such as a photoconductor drum, or any other location that can be fixed in the housing. More specifically, for example, a member connected to a rotating shaft of a rotating photosensitive drum.

  The Selfoc lens unit is fixed to the housing so as to be disposed between the line head and the photoconductor, and guides the refracted light to the photoconductor by refracting the light. More specifically, the SELFOC lens array only needs to be directly or indirectly fixed to the housing, and the photosensitive member is exposed by light emitted from the line head. Note that the photoconductor can be exposed with high accuracy in a state where the distance between the SELFOC lens array and the photoconductor is short, and an image forming apparatus such as a printer can be downsized. Here, the close state means, for example, a case where the light emitted from the line head is guided to the photosensitive member using other lenses excluding the Selfoc lens array. That is, according to the SELFOC lens array, for example, the light that forms an image with the same magnification as that of the photoconductor is guided to the photoconductor as compared with the case where the light emitted from the light emitting unit is guided to the photoconductor using another lens. In addition, since the imaging distance can be shortened, the image forming apparatus can be miniaturized and the image quality can be improved.

  The positioning means is, for example, a member extending toward the line head side and the photoreceptor side with reference to the Selfoc lens array, and at least one of the line head and the photoreceptor separately from the Selfoc lens array is used as the positioning means. At the time of replacement, the position of the newly installed line head and / or photoconductor is determined by one end or the other end of the positioning means. By contacting the one end or the other end of the positioning means, the line head and the photoconductor can be positioned without performing a complicated positioning operation using the adjusting mechanism. Here, the length from one end to the other end of the positioning means extending toward the line head side and the photoconductor side with reference to the Selfoc lens array is the object distance and image plane of the Selfoc lens array. Since the distance between the line head and the photoconductor is set to be equal to the conjugate length of the Selfoc lens array, for example, the line head and the photoconductor to be replaced according to their lifetimes. Positioning can be performed easily. The “object distance” means a distance to a plurality of light emitting units and the Selfoc lens array that are light sources, and more specifically, faces a plurality of light emitting units among both the plurality of light emitting units and the Selfoc lens array. It means the distance to the side surface. “Image plane distance” means the distance between the photoconductor and the Selfoc lens array, and more specifically, the distance to the surface facing the photoconductor of both sides of the photoconductor and the Selfoc lens array. To do. Further, “based on the Selfoc lens array” means, for example, an object distance that is a distance from the Selfoc lens array to one end of the positioning means that contacts the line head, and from the Selfoc lens array to the photosensitive member. This means that the image plane distances, which are the distances to the other end in contact with each other, are equal to each other, or are coincident to the extent that they can be considered to be equal. The “distance between the line head and the photoconductor” means the sum of the object distance, the thickness of the SELFOC lens array, and the image plane distance, and more specifically, the distance between the line head and the photoconductor. Includes a case where the length is equal to the conjugate length of the SELFOC lens array or coincides with the conjugate length to the extent that it can be considered to be practically equal. Since the “distance between the line head and the photoconductor” is equal to the conjugate length, or equal to the extent that it can be regarded as actually matching, the image quality of the image formed by the image forming apparatus can be maintained at a high quality. The “conjugate length” is determined according to the wavelength of the light emitted from the light emitting unit. For example, when light of a certain wavelength is emitted from a plurality of light emitting units, the thickness of the SELFOC lens array varies. Accordingly, the length of the positioning means is set.

  According to the image forming apparatus of the present invention, a photosensitive member such as a photosensitive drum can be exposed at a high speed and with a high resolution, and then a high-speed and high-quality color image, a black-and-white image, or characters can be copied on a copy sheet through subsequent development and transfer. It can be formed on a recording medium such as

  As described above, according to the image forming apparatus of the present invention, since the SELFOC lens array, the line head, and the photoconductor are separate bodies, only the photoconductor or the line head whose characteristics have deteriorated due to the lifetime are replaced. The usable SELFOC lens array can be used as it is. Thereby, the unit price of the Selfoc lens can be reduced out of the running cost of the image forming apparatus. In addition, since the positioning of the line head or the photosensitive member, which has been a problem when replacing the line head or the photosensitive member, can be simplified, the image quality is reduced or reduced without providing a separate positioning mechanism for positioning the line head and the photosensitive member. Variations can be suppressed. In particular, when a Selfoc lens array is used, the positional relationship between the line head and the photoconductor with respect to the Selfoc lens array is important. Therefore, the image forming apparatus according to the present invention is capable of maintaining image quality and the like. It has a very effective configuration.

  In one aspect of the image forming apparatus according to the present invention, the image forming apparatus further includes a fixing unit that fixes the Selfoc lens array to the housing, and the positioning unit is located on the line head side and the photoconductor side from the fixing unit. It may be a rod-shaped body extending toward the surface.

  According to this aspect, for example, the line head and the photoconductor can be positioned by a rod-like body such as a door stop extending from the fixing member that fixes the SELFOC lens array to the housing to each of the line head and the photoconductor. Accordingly, the line head and the photoconductor can be accurately positioned without providing an adjusting mechanism for individually adjusting the positions of the line head and the photoconductor, and without taking time and effort.

In this aspect, the fixing means is a plate-like member extending along an in-plane direction that intersects the direction from the line head toward the photoconductor.
A plurality of the rod-like bodies may be provided at predetermined intervals on each surface of the plate-like member facing the line head side and the photoconductor side.

  According to this aspect, since the SELFOC lens array is fixed to the housing by the plate-like member extending along the in-plane direction intersecting the direction from the line head toward the photoconductor, the line head and the photoconductor The whole can be positioned. More specifically, since a plurality of rod-like bodies serving as positioning means are provided at predetermined intervals on each surface of the plate-like member facing the line head side and the photoconductor side, for example, the line head and the photoconductor One end or the other end of the rod state is in uniform contact with the entire body, so that the line head and the entire photoreceptor can be positioned uniformly. Therefore, for example, an electrostatic latent image to be formed on the photosensitive member can be accurately formed by light emitted from the entire plurality of light emitting units.

  In another aspect of the image forming apparatus according to the present invention, the Selfoc lens array may include a plurality of Selfoc lenses arranged in a line so as to face each of the plurality of light emitting units. .

  According to this aspect, the light emitted from the plurality of light emitting units is incident on each of the Selfoc lenses constituting the Selfoc lens array, and an electrostatic latent image can be formed on the photosensitive member by the entire light.

  In another aspect of the image forming apparatus according to the present invention, the light emitting section may include an organic EL element.

  According to this aspect, for example, the line head can be replaced according to the lifetime of the organic EL element, and the cost of the image forming apparatus can be reduced as compared with the case where the Selfoc lens array is replaced together with the line head. In addition, the line head can be easily positioned, and stable image quality and print quality can be maintained by utilizing the characteristics of the SELFOC lens array.

  Such an operation and other advantages of the present invention will become apparent from the embodiments described below.

  Hereinafter, a printer 1 as an example of an image forming apparatus according to the present invention will be described with reference to the drawings.

  First, the overall configuration of the printer 1 will be described with reference to FIG. FIG. 1 is a schematic cross-sectional view showing the overall configuration of the printer 1 according to the present embodiment.

  In FIG. 1, a printer 1 is an example of a cover 2 as an example of a “casing” according to the present invention, a printer head 3 as an example of a “line head” according to the present invention, and an example of a “photosensitive member” according to the present invention. A photosensitive drum 4, a support unit 5, a Selfoc lens array 6, a rod-like body 7 as an example of a “positioning unit” according to the present invention, a transfer belt 8, a transport device 9, a cleaner 20, a charger 19, and a developer 18. It has. The printer head 3, the selfoc lens array 6 and the photosensitive drum 4 are arranged in the order of the printer head 3, the selfoc lens array 6 and the photosensitive drum 4 when viewed from the printer head 3 side. In the present embodiment, the overall configuration of the image forming apparatus according to the present invention will be described by taking a printer including one photosensitive drum as an example. The image forming apparatus according to the present invention includes a plurality of printer units. A color printer may be used.

  The cover 2 means a case or the like that stores each component constituting the printer 1.

  The printer head 3 includes a substrate 10 and a plurality of light emitting units 11 arranged in a line on the substrate 10, and is detachably attached to the cover 2 via an attachment unit 15. Therefore, when the light emitting element included in the light emitting unit 1 deteriorates, the photosensitive drum 4 can be exposed again by replacing the new printer head with the mounting unit 15. The substrate 10 has a shape extending in the longitudinal direction along the depth direction in the drawing, that is, the direction orthogonal to the paper surface, and is formed of, for example, a glass substrate, a quartz substrate, or a semiconductor substrate.

  The printer head 3 is arranged such that an area where a plurality of light emitting units 11 are arranged faces the photosensitive drum 4 side, and has a size that allows the printer 1 to print on printing paper of various sizes. The size of the printer head 3 along the longitudinal direction is, for example, 20 to 30 cm so that it can be printed on A size printing paper. Note that the printer head 3 may include an external circuit connection terminal, a data line circuit, and a line scanning circuit. The printer head 3 is sensitized by a data signal and a scanning signal supplied to each light emitting unit 11 via these terminals and circuits. A required electrostatic latent image can be formed on the exposed surface of the drum 4. The light emitting unit 11 includes, for example, an organic EL element, and lighting and non-lighting, that is, on / off are controlled according to the data signal and the scanning signal. The specific layout of the plurality of light emitting units 11 will be described in detail later.

  The support portion 5 is a member that supports the photosensitive drum 4 while fixing the photosensitive member such as the photosensitive drum 4 to the cover 2 or another portion provided in the space in the cover 2, for example. More specifically, it is a member that is detachably attached to the rotating shaft 17 of the photosensitive drum 4 as shown. Therefore, when the photosensitive drum 4 is deteriorated, it is possible to remove the photosensitive drum 4 from the support portion 5 and to scatter a new photosensitive drum on the support portion 5 via the rotating shaft 17.

  The Selfoc lens array 6 is fixed to the cover 2 via a lens fixing portion 16 so as to be disposed between the printer head 10 and the photosensitive drum 4. The Selfoc lens array 6 refracts the light emitted from the printer head 3 and guides the refracted light to the exposure surface of the photosensitive drum 4, thereby forming a required electrostatic latent image on the exposure surface of the photosensitive drum 4. To do. According to the SELFOC lens array 6, it is possible to form an image on the exposure surface with high accuracy in a state where the distance between the exposure surface of the SELFOC lens array 6 and the photosensitive drum 4 is short by utilizing the lens characteristics. The image forming apparatus such as the printer 1 can be downsized.

  Here, the “close state” means, for example, the SELFOC lens array 3 and the photosensitive drum as compared to the case where the light emitted from the printer head is guided to the photosensitive drum 4 using other lenses than the SELFOC lens array 6. 4 means that the distance between the exposure surfaces is short. That is, according to the SELFOC lens array 6, the light that forms an image with the same magnification as that of the photosensitive drum 4 is used as compared with the case where the light emitted from the light emitting unit 11 is guided to the photosensitive drum 4 using another lens. Since the imaging distance can be shortened, the printer 1 can be downsized and the image quality can be improved.

  The rod-shaped body 7 is a member that extends toward the printer head 3 side and the photosensitive drum 4 side with reference to the Selfoc lens array 6. The rod-shaped body 7 functions, for example, as a door stop extending from the fixing portion 16 that fixes the SELFOC lens array 6 to the cover 2 to each of the printer head 3 side and the photosensitive drum 4 side body. Positioning can be performed easily and accurately.

  More specifically, the rod-like body 7 extends from the fixing portion 16 that fixes the SELFOC lens 6 to the cover 2 toward the printer head 3 and the photosensitive drum 4. When at least one of the printer head 3 and the photosensitive drum 4 separated from the Selfoc lens array 6 is exchanged, the support 15 for supporting the mounting portion 15 for fixing the newly installed printer head 3 or the photosensitive drum 4 is supported. The part 5 or both abut against the one end 40a and the other end 40b of the rod-like body 7, respectively, and the printer head 3 and the photosensitive drum 4 are positioned accordingly.

  In addition, in this embodiment, it is not limited to the case where the other end 40b of the rod-shaped body 7 abuts on the attachment portion 15, and the other end 40b may be directly on the substrate 10 constituting the printer head 3. Of course. In addition, as will be described later with reference to FIG. 2, the distance from the Selfoc lens array 6 to the printer head 3, the distance from the Selfoc lens array 6 to the photosensitive drum 4, and from the printer head 3 to the photosensitive drum 4. Since the length of the rod-like body 7 is set so that the distance between them is a predetermined distance, the newly arranged printer head 3 and the photosensitive drum 4 can be positioned at predetermined positions, and the lenses of the SELFOC lens array 6 can be positioned. It is possible to take advantage of the characteristics, and there is no need to provide a separate complicated positioning mechanism. Therefore, the printer 1 can reduce the position adjustment mechanism, and can replace only the printer head 3 and the photosensitive drum 4, thereby increasing the running cost of the printer 1 caused by replacing the usable Selfoc lens array 6. Can be suppressed. As described above, according to the rod-like body 7, the printer head 3 and the photosensitive drum 4 can be easily and without the need to provide an adjustment mechanism for individually adjusting the positions of the replaced printer head 3 and the photosensitive drum 4. Positioning can be performed with high accuracy.

  The transfer belt 8, the transport device 9, the cleaner 20, the charger 19 and the developing device 18 constitute an example of “image forming unit” according to the invention.

  After the toner remaining on the exposed surface of the photosensitive drum 4 in the previous cycle is removed by the cleaner 20, the exposed surface of the photosensitive drum 4 is charged by corona discharge or the like by the charger 19 for the current cycle. Subsequently, an electrostatic latent image corresponding to the data signal or the like is formed on the exposed surface of the photosensitive drum 4 by exposure corresponding to the data signal or the like by the printer head 3. Development is performed by a developing device using toner, and a toner image as a visible image is formed on the exposed surface of the photosensitive drum 4 by toner adhesion. At a transfer position facing the photosensitive drum 4, the toner image on the photosensitive drum 4 is transferred to the transfer belt 8 driven by the rollers 22 and 23 while being pressed from the back side by the transfer roller 23. The transferred toner image is transferred by the transport device 9 onto a paper 21 that is a recording medium such as a copy paper to be transported. Then, the image-formed paper 21 is discharged onto a discharge tray via a fixing device (not shown).

  Next, the positional relationship among the SELFOC lens array 6, the printer head 3, and the photosensitive drum 4 will be described in detail with reference to FIG. FIG. 2 is a schematic cross-sectional view illustrating a configuration of a main part of the printer 1. For convenience of explanation, the photosensitive drums 4, the selfoc lens array 6, and the printer head 3 arranged in the diagonal direction in FIG. 1 are illustrated so as to be sequentially arranged in the horizontal direction in FIG. ing.

  In FIG. 2, the SELFOC lens 6 is fixed to the cover 2 via a fixing portion 16 having a portion extending in the vertical direction in the figure. The fixing portion 16 may have any shape as long as the Selfoc lens 6 can be fixed to the cover 2. For example, the fixing portion 16 is connected to a partial region of the Selfoc lens array 6 along the depth direction in the drawing. It is a member. More preferably, the fixing portion 16 is a plate-like member extending along an in-plane direction that intersects the direction from the printer head 3 toward the photosensitive drum 4, for example. A plurality of them may be provided at predetermined intervals on each surface facing the printer head 3 side and the photosensitive drum 4 side.

  According to the fixing portion 16 and the rod-like body 7, a plurality of fixing portions 16 and a plurality of support portions 5 are provided along the depth direction in the drawing, that is, along the direction in which the printer head 3 and the photosensitive drum 4 extend. The rod-shaped body 7 is in contact with each of the attachment portion 15 and the support portion 5 uniformly. As a result, the entire printer head 3 and the photosensitive drum 4 can be arranged so as to maintain a predetermined distance, which will be described later, with respect to the SELFOC lens array 6, and formed on the photosensitive drum 4 by the light emitted from the plurality of light emitting units 11. It is possible to accurately form an electrostatic latent image. The support portion 5 and the attachment portion 15 may be provided so as to extend below the printer head 3 and the photosensitive drum 4, and the support portion 5 and the attachment portion 15 that extend downward in the drawing are provided. A rod-like body 7 may be provided on the lower side of the Selfoc lens array 6 in the figure so as to be in contact with each other.

  The SELFOC lens array 6 is fixed to the cover 2 via a fixing portion 16 so as to be disposed between the printer head 3 and the photosensitive drum 4, and this refraction is performed by refracting light emitted from the printer head 3. The emitted light is guided to the exposure surface of the photosensitive drum 4. The Selfoc lens array 6 may be indirectly fixed to the cover 2 via the fixing portion 16 or may be directly fixed to the cover 2. When the self-floc lens array 6 is directly fixed to the cover 2, the rod-like body 7 is provided so as to extend from the Selfoc lens array 6 to the printer head 3 side and the photosensitive drum 4 side, respectively.

  The length from one end to the other end of the rod-like body 7 extending from the fixed portion 16 toward the printer head 3 and the photosensitive drum 4n with reference to the Selfoc lens array 6 is the object distance and the image of the Selfoc lens array 6. The surface distances are equal, and the distance between the printer head 3 and the photosensitive drum 4 is set to be the conjugate length of the SELFOC lens array 6.

  Here, the “object distance” means the distance to the light emitting units 11 and the Selfoc lens array 6 that are light sources, and more specifically, on both surfaces of the plurality of light emitting units 11 and the Selfoc lens array 6. Of these, the distance to the surface facing the plurality of light emitting units 11 is meant. “Image surface distance” means the distance between the photosensitive drum 4 and the Selfoc lens array 6, and more specifically, the exposure surface of the photosensitive drum 4 and both surfaces of the Selfoc lens array 6 face the photosensitive drum 4. It means the distance to the side surface.

  Further, “using the SELFOC lens array 6 as a reference” means centering on the SELFOC lens array 6 along the left-right direction in the drawing. For example, the SELFOC lens array 6 contacts the printer head 3. The object distance, which is the distance to one end, and the image plane distance, which is the distance from the SELFOC lens array 6 to the other end in contact with the support portion 5 that supports the photosensitive drum, are equal to each other, or can be regarded as practically equal. Means that The distance between the printer head 3 and the photosensitive drum 4 means the sum of the object distance, the thickness of the SELFOC lens array 6 and the image plane distance, and more specifically, between the printer head 3 and the photosensitive drum 4. Is equal to the conjugate length of the SELFOC lens array 6 to the extent that it can be considered to be equal to or practically equal to the conjugate length of the SELFOC lens array 6. Since the distance between the printer head 3 and the photosensitive drum 4 is equal to the conjugate length, or to the extent that it can be regarded as actually matching, the image quality of the image formed by the printer head 3 can be maintained at high quality.

  The “conjugate length” is determined according to the wavelength of the light emitted from the light emitting unit 11. For example, when light having a certain wavelength is emitted from the plurality of light emitting units 11, the thickness of the SELFOC lens array 6. The length of the rod-shaped body 7 is set according to the variation such as the above.

  Therefore, in FIG. 2, the distance from the Selfoc lens array 6 to the printer head 3 is Li, the distance from the exposure surface of the photosensitive drum 4 to the Selfoc lens 6 is L0, and the thickness of the Selfoc lens array 6 is Z0. The length of the rod-like body 7 is set so that the distance TC between the printer head 3 and the photosensitive drum 4 positioned by contacting both ends of the rod-like body 7 satisfies (Equation 1).

TC = LO + Li + Z0 (Formula 1)
As described above, according to the printer 1 according to the present embodiment, since the SELFOC lens array 6, the printer head 3, and the photosensitive drum 4 are separate bodies, the printer head 3 or the photosensitive drum whose characteristics have deteriorated due to the lifetime. 4 can be exchanged, and the usable SELFOC lens array 6 can be used as it is. Thereby, the running cost of the printer 1 can be reduced. In addition, in the printer 1 equipped with the Selfoc lens array 6, the positioning of the printer head 3 or the photosensitive drum 4 which is a concern when the printer head 3 or the photosensitive drum 4 is replaced can be simplified. It is possible to suppress deterioration or variation in image quality without providing it. In the printer 1 having the Selfoc lens array 6, the positional relationship between the printer head 3 and the photosensitive drum 4 with respect to the Selfoc lens array 6 is important. Therefore, the printer 1 according to the present embodiment maintains image quality and the like. Therefore, it has a very effective configuration.

  Next, the positional relationship between the Selfoc lens array 6 and the printer head 3 will be described with reference to FIG. FIG. 3 is a perspective view showing the positional relationship between the Selfoc lens array 6 and the printer head 3.

  In FIG. 3, the SELFOC lens array 6 includes a base member 30 and a plurality of lenses 31 arranged in a line along the longitudinal direction of the base member 30. The substrate 10 provided in the printer head 3 extends along the longitudinal direction of the Selfoc lens array 6, and the Selfoc lens so that the plurality of light emitting units 11 arranged in a line on the substrate 10 face the lens 31. A printer head 3 is arranged with respect to the array 6. For convenience of explanation, the light emitting unit 11 is shown larger than the size of the lens 31.

  According to the printer head 3 and the Selfoc lens array 6 arranged in this way, light emitted from the plurality of light emitting units 11 is incident on the lenses 31 constituting the Selfoc lens array 6 and is emitted from the plurality of light emitting units 11. An electrostatic latent image can be formed on the exposed surface of the photosensitive drum 4 by the entire emitted light.

  Next, various specific examples of the planar layout of the light emitting units 11 arranged in the printer head 3 will be described with reference to FIG. FIG. 4 is a schematic partial enlarged view of the printer head 3. In the following description, common parts are denoted by common reference numerals in the specific examples.

  In FIG. 4, the plurality of light emitting portions 11 are arranged along a line direction that coincides with the longitudinal direction of the substrate 10, and each includes an organic EL element as a light emitting element. The plurality of light emitting units arranged in a line are, for example, organic EL elements arranged in a line. Here, “arranged in a line” includes not only extending in a single line along the line direction in which a plurality of light emitting units are arranged, but also extending in two or more lines, or extending in a staggered pattern. . The line head having the light emitting units arranged in a line shape emits light in a line shape from the light emitting element array sequentially along the line direction in which the light emitting units are arranged. Is possible. Alternatively, line-shaped light can be emitted from the light-emitting element array at the same time or a part thereof.

  More specifically, the light emitting unit 11 may be provided with one line (FIG. 4A), a plurality of lines may be provided in a staggered pattern (FIG. 4B), or a matrix. A plurality of lines may be provided in a shape (FIG. 4C). In any specific example, the light emitting unit 11 is provided for each pixel circuit 201. The pixel circuit 201 including the light emitting unit 11 is supplied with a scanning signal from the line scanning circuit via the line scanning signal line 141 and a data signal via the lead line portion 113 c of the data line unit 113. Further, a high potential power supply and a low potential power supply 118 are supplied from a high potential wiring 116 and a low potential wiring 118, respectively. The light emitted from each of the light emitting units 11 arranged in this way is guided to the photosensitive drum 4 via the selfoc lens array 6 facing the light emitting units 11, and the electrostatic latent image is formed on the exposure surface of the photosensitive drum 4. An image can be formed. According to the printer head, the SELFOC array, and the photosensitive drum having the light emitting units 11 arranged in this way, the printer 1 according to the present embodiment uses the characteristics of the SELFOC lens 6 while running the printer head. Cost can be reduced. In addition, the light emission part 11 is not limited to the light emission part of this embodiment, Of course, you may be comprised including light emitting elements other than an organic EL element.

  Note that the present invention is not limited to the above-described embodiments, and can be appropriately changed within the scope of the invention or the concept that can be read from the claims and the entire specification, and an image accompanying such a change. It goes without saying that the forming apparatus is also included in the technical scope of the present invention.

1 is a schematic cross-sectional view illustrating an overall configuration of a printer according to an embodiment. FIG. 2 is a schematic cross-sectional view illustrating a configuration of a main part of the printer according to the embodiment. 3 is a perspective view showing a positional relationship between a Selfoc lens array 6 and a printer head 3 provided in the printer according to the present embodiment. FIG. FIG. 3 is a schematic partial enlarged view of a printer head 3 provided in the printer according to the present embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Printer, 2 ... Cover, 3 ... Printer head, 4 ... Photosensitive drum, 5 ... Support part, 6 ... Selfoc lens array, 7 ... Rod-shaped body

Claims (5)

A housing,
A line head having a plurality of light emitting portions arranged in a line; and
A photoreceptor that is an irradiation destination of light emitted from the plurality of light emitting units;
A support for supporting the photoreceptor;
A selfoc lens array that is fixed to the housing so as to be disposed between the line head and the photoconductor, and refracts the light to guide the refracted light to the photoconductor;
It extends toward each of the line head side and the photoconductor side with respect to the selfoc lens array, and comes into contact with one end for determining the position of the line head and the support portion by contacting the line head. Positioning means having the other end for determining the position of the photoreceptor by
Image forming means for forming a visible image on a recording medium based on the electrostatic latent image formed on the photoreceptor,
The length from the one end to the other end so that the object distance and the image plane distance of the Selfoc lens array are equal, and the distance between the line head and the photoconductor is the conjugate length of the Selfoc lens array. An image forming apparatus characterized in that is set. A fixing means for fixing the Selfoc lens array unit to the case;
The image forming apparatus according to claim 1, wherein the positioning unit is a rod-shaped body extending from the fixing unit toward the line head side and the photoconductor side. The fixing means is a plate-like member extending along an in-plane direction that intersects the direction from the line head toward the photoconductor.
The image forming apparatus according to claim 2, wherein a plurality of the rod-shaped bodies are provided at a predetermined interval on each surface of the plate-shaped member facing the line head side and the photoconductor side. 4. The image according to claim 1, wherein the Selfoc lens array includes a plurality of Selfoc lenses arranged in a line so as to face each of the plurality of light emitting units. 5. Forming equipment. The image forming apparatus according to any one of claims 1 to 4, wherein the light emitting unit includes an organic EL element.

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