JP6296325B2 - Exposure equipment - Google Patents

Description

The present invention relates to an exposure apparatus for image forming apparatus having the light shielding member.

  A conventional image forming apparatus condenses laser light emitted from a single laser light source on a photosensitive surface through an fθ lens while deflecting the laser light in a main scanning direction by a rotary polygon mirror. On the other hand, by using a line head in which light sources are arranged on a line, an image forming apparatus has been developed that forms an image by scanning a light beam on the surface of a photoreceptor without using a rotating polygon mirror (Patent Document 1). reference). In such an image forming apparatus, a lens array having a plurality of lenses arranged on a line corresponding to the light source is provided instead of the fθ lens.

  Furthermore, in the configuration of Patent Document 1, a light shielding member having a plurality of holes is used to individually separate the spaces between the plurality of light sources and the lenses of the lens array, and light from each light source is adjacent to the space or By leaking outside, so-called crosstalk is suppressed. This is because when crosstalk occurs, a ghost is generated, the latent image formed on the photosensitive member becomes unclear, and the image quality of the image formed by the image forming apparatus is also deteriorated.

JP 2008-87352 A

  However, according to the disclosure of Patent Document 1, it is suggested that a metal, a resin, or the like is used for the light shielding member. However, when a hole is formed in a metal or a resin material, the inner peripheral surface of the hole is generally Since it is mirror-finished, the light reflected by the inner peripheral surface becomes stray light and may cause ghost.

An object of the present invention is to provide an exposure apparatus for an image forming apparatus that can form a high-quality image at a lower cost.

In order to achieve at least one of the objects described above, an exposure apparatus for an image forming apparatus reflecting one aspect of the present invention includes the following.
An exposure apparatus for an image forming apparatus is
A plurality of light sources provided on the substrate;
A lens array comprising a plurality of lenses;
A light-shielding member disposed between the substrate and the lens array, and provided with a hole for each lens to pass a light beam emitted from the light source and incident on the lens;
A gap is provided between the light shielding member and the lens array,
At least the inner peripheral surface of the hole of the light shielding member is porous.

According to the present invention, it is possible to provide an exposure apparatus for an image forming apparatus that can form a high-quality image at a lower cost.

1 is a cross-sectional view showing an image forming apparatus 1 having a line head 29 as an exposure apparatus according to the present embodiment. FIG. 2 is a diagram illustrating an electrical configuration of the image forming apparatus 1 and the line head 29 in FIG. 1. It is a perspective view which shows the outline of the line head 29 concerning this Embodiment. 3 is a schematic sectional view of a line head 29. FIG. It is a figure which shows arrangement | positioning of the several light emitting element group 295. FIG. It is a figure which shows the manufacturing process of the light shielding member 297. FIG. It is a figure which shows the manufacturing process of the light shielding member 297. FIG. It is a figure which shows the manufacturing process of the light-shielding member 297 concerning a modification.

  Embodiments according to the present invention will be described below with reference to the drawings. However, although various technically preferable limitations for carrying out the present invention are given to the embodiments described below, the scope of the invention is not limited to the following embodiments and illustrated examples.

  As the “light source”, for example, an OLED (Organic Light Emitting Diode) in which a plurality of light emitting points are arranged in a line (including a plurality of rows) or an LED (Light Emitting Diode) chip is preferably arranged in a line. . In addition, it is preferable to use a porous material having a porosity of 45 to 90% as the light shielding member because an effective antireflection performance can be secured. As such a porous material, urethane or the like that can be easily cut and molded can be used. In particular, urethane has an advantage that the processing equipment can be simplified because the light guide hole can be punched with a low load. Moreover, the porous material such as urethane can select the size of the material relatively easily and can secure the necessary length of the light guide hole, so that the increase in the number of parts can be suppressed. The formation of the light guide hole is preferably performed by punching. The reason is that if the hole for light guide is processed by cutting, the number of man-hours increases because it is not possible to process a plurality of holes at one time. On the other hand, if the hole for light guide is processed by etching, a thick material This is because it is difficult to control the cross-sectional shape. By performing the punching process for the light guide holes, a plurality of light guide holes can be accurately formed at a time. When performing punching, it is preferable to use a pinnacle die having a processing accuracy equivalent to that of a punching machine, although it has a relatively simple equipment configuration. Thereby, the exposure apparatus can be manufactured at low cost. The light shielding member is preferably attached to the substrate or the lens array because the influence of thermal expansion can be suppressed. Further, when the surface other than the hole of the light shielding member is porous, reflection of light incident on the surface can be suppressed and stray light can be suppressed.

  FIG. 1 is a sectional view showing an image forming apparatus 1 having a line head 29 as an exposure apparatus according to the present embodiment. FIG. 2 is a diagram showing an electrical configuration of the image forming apparatus 1 and the line head 29 shown in FIG.

  The image forming apparatus 1 includes a color mode in which four color toners of black (K), cyan (C), magenta (M), and yellow (Y) are superimposed to form a color image, and only black (K) toner. It is possible to selectively execute a monochrome mode for forming a monochrome image using. In FIG. 1, the image forming apparatus 1 includes a line head 29 for forming an image corresponding to each color. FIG. 1 shows a state when the color mode is executed.

  In FIG. 2, in the image forming apparatus 1, when an image forming command is given from an external device such as a host computer to a main controller MC having a CPU, a memory, etc., the main controller MC sends a control signal to the engine controller EC. In addition, the video data VD corresponding to the image formation command is supplied to the head controller HC. The head controller HC controls the line head 29 for each color based on the video data VD from the main controller MC, the vertical synchronization signal Vsync from the engine controller EC, and parameter values. As a result, the engine unit EG executes a predetermined image forming operation to form an image corresponding to the image forming command on a sheet such as a copy sheet, a transfer sheet, a sheet, and an OHP transparent sheet.

  In FIG. 1, the image forming apparatus 1 includes a housing body 3. In the housing main body 3, an electrical component box 5 is provided that contains a power circuit board, a main controller MC, an engine controller EC, and a head controller HC. In addition, the image forming unit 7, the transfer belt unit 8, and the paper feeding unit 11 are disposed in the housing body 3. Further, a secondary transfer unit 12, a fixing unit 13, and a sheet guide member 15 are disposed in the housing body 3. Note that the paper feed unit 11 and the transfer belt unit 8 can be removed and repaired or exchanged.

  The image forming unit 7 includes four image forming stations YST (for yellow), MST (for magenta), CST (for cyan), and KST (for black) that form a plurality of images of different colors. In each of the image forming stations YST, MST, CST, and KST, a photosensitive drum 21 is provided as a latent image carrier on which a toner image of each color is formed. Each photoconductor drum 21 is connected to a dedicated drive motor, and is driven to rotate at a predetermined speed in the direction of arrow D21 in the figure. As a result, the surface 211 of the photosensitive drum 21 as the surface to be scanned is conveyed in the sub-scanning direction.

  A charging unit 23, a line head 29, a developing unit 25, and a photoconductor cleaner 27 are disposed around the photoconductive drum 21 along the rotation direction. Thus, a charging operation, an electrostatic latent image forming operation, a toner developing operation, and a cleaning operation are executed, respectively. When the color mode is executed, the toner images formed at all the image forming stations YST, MST, CST, and KST are superimposed on the transfer belt 81 of the transfer belt unit 8 to form a color image, and when the monochrome mode is executed. Can form a monochrome image using only the toner image formed at the image forming station KST.

  The charging unit 23 includes a charging roller whose surface is made of elastic rubber. The charging roller is configured to rotate in contact with the surface 211 of the photosensitive drum 21 at the charging position, and rotates in the driven direction with respect to the photosensitive drum 21 as the photosensitive drum 21 rotates. Driven at high speed. The charging roller is connected to a charging bias generation unit (not shown). The charging roller is supplied with the charging bias from the charging bias generation unit and is charged at a charging position where the charging unit 23 and the photosensitive drum 21 come into contact with each other. 21 surface 211 is charged.

  The line head 29 has a function of irradiating the surface 211 of the photosensitive drum 21 charged by the charging unit 23 with light to form an electrostatic latent image on the surface 211.

  Hereinafter, the control of the line head 29 will be described in detail with reference to FIG. In the present embodiment, the image data included in the image formation command is input to the image processing unit 51 of the main controller MC. Various image processing is performed on the image data to create video data VD of each color, and the video data VD is given to the head controller HC via the main-side communication module 52. In the head controller HC, the video data VD is given to the head control module 54 via the head side communication module 53. As described above, the head controller module 54 is supplied with the signal indicating the parameter value related to the electrostatic latent image formation and the vertical synchronization signal Vsync from the engine controller EC. Based on these signals, video data VD, and the like, the head controller HC creates signals for controlling element driving for the line heads 29 of the respective colors, and outputs the signals to the line heads 29. Thus, the operation of the light emitting element 2951 (see FIG. 3) (not shown) is appropriately controlled in each line head 29, and an electrostatic latent image corresponding to the image formation command is formed. The configuration of the line head 29 including the light emitting element 2951 will be described in detail later.

  The developing unit 25 has a developing roller 251 that carries toner on the surface thereof. The charged toner is developed at a developing position where the developing roller 251 and the photosensitive drum 21 come into contact with each other by a developing bias applied to the developing roller 251 from a developing bias generating unit (not shown) electrically connected to the developing roller 251. The electrostatic latent image formed by the line head 29 by moving from the roller 251 to the photosensitive drum 21 is manifested to become a toner image.

  The toner image that has been made visible at the development position in this way is conveyed in the rotational direction D21 of the photosensitive drum 21, and then the primary transfer position TR1 where the transfer belt 81, which will be described in detail later, and each photosensitive drum 21 come into contact with each other. 1 is primarily transferred to the transfer belt 81.

  In the present embodiment, the photoreceptor cleaner 27 is in contact with the surface 211 of the photoreceptor drum 21 on the downstream side of the primary transfer position TR1 in the rotation direction D21 of the photoreceptor drum 21 and on the upstream side of the charging unit 23. Is provided. The photosensitive cleaner 27 has a function of cleaning and removing toner remaining on the surface 211 of the photosensitive drum 21 after the primary transfer by contacting the surface 211 of the photosensitive drum 21.

  In this embodiment, the photosensitive drum 21, the charging unit 23, the developing unit 25, and the photosensitive cleaner 27 of each image forming station YST, MST, CST, and KST are unitized as a photosensitive cartridge. Each photoconductor cartridge is provided with a nonvolatile memory for storing information related to the photoconductor cartridge. Then, wireless communication is performed between the engine controller EC and each photoconductor cartridge. In this way, information on each photoconductor cartridge is transmitted to the engine controller EC, and information in each memory is updated and stored.

  The transfer belt unit 8 includes a driving roller 82, a driven roller 83 (blade facing roller) disposed on the left side of the driving roller 82 in FIG. 1, and stretched around these rollers in a direction indicated by an arrow D81 (conveying direction). And a transfer belt 81 that is driven to circulate. Further, the transfer belt unit 8 is disposed on the inner side of the transfer belt 81 so as to be opposed to each of the photosensitive drums 21 included in each of the image forming stations YST, MST, CST, and KST when the photosensitive cartridge is mounted. Four primary transfer rollers 85Y, 85M, 85C, and 85K are provided. These primary transfer rollers 85Y, 85M, 85C, and 85K are electrically connected to a primary transfer bias generator (not shown). As described in detail later, when the color mode is executed, as shown in FIG. 1, all the primary transfer rollers 85Y, 85M, 85C, and 85K are positioned on the image forming stations YST, MST, CST, and KST side. Thus, the transfer belt 81 is pressed against and brought into contact with the photosensitive drums 21 included in the image forming stations YST, MST, CST, and KST, and a primary transfer position TR1 is defined between each photosensitive drum 21 and the transfer belt 81. To do. Then, the toner formed on the surface 211 of each photosensitive drum 21 by applying the primary transfer bias to the primary transfer rollers 85Y, 85M, 85C, and 85K from the primary transfer bias generation unit at an appropriate timing. The image is transferred to the surface of the transfer belt 81 at the corresponding primary transfer position TR1 to form a color image.

  On the other hand, when executing the monochrome mode, among the four primary transfer rollers, the color primary transfer rollers 85Y, 85M, and 85C are separated from the image forming stations YST, MST, and CST that face each other, and the monochrome primary transfer roller 85K. Only the monochrome image forming station KST is brought into contact with the transfer belt 81 by contacting only the image forming station KST. As a result, the primary transfer position TR1 is defined only between the monochrome primary transfer roller 85K and the image forming station KST. Then, by applying a primary transfer bias from the primary transfer bias generator to the monochrome primary transfer roller 85K at an appropriate timing, the toner image formed on the surface 211 of each photosensitive drum 21 is converted into a primary image. A monochrome image can be formed by transferring to the surface of the transfer belt 81 at the transfer position TR1.

  Further, the transfer belt unit 8 includes a downstream guide roller 86 disposed downstream of the monochrome primary transfer roller 85K and upstream of the drive roller 82. Further, the downstream guide roller 86 is formed between the primary transfer roller 85K and the photosensitive drum 21 at the primary transfer position TR1 formed by the monochrome primary transfer roller 85K contacting the photosensitive drum 21 of the image forming station KST. It is configured to contact the transfer belt 81 on a common inscribed line.

  The paper feed unit 11 includes a paper feed unit having a paper feed cassette 77 capable of stacking and holding sheets and a pickup roller 79 for feeding sheets one by one from the paper feed cassette 77. The sheet fed from the sheet feeding unit by the pickup roller 79 is fed to the secondary transfer position TR2 along the sheet guide member 15 after the sheet feeding timing is adjusted by the registration roller pair 80.

  The secondary transfer unit 12 includes a secondary transfer roller 121 and a driving roller 82. A driving roller 82 that circulates and drives the transfer belt 81 in the direction of the arrow D 81 in the drawing also serves as a backup roller for the secondary transfer roller 121. A rubber layer having a thickness of about 3 mm and a volume resistivity of 1000 kΩ · cm or less is formed on the peripheral surface of the drive roller 82, and a secondary transfer bias (not shown) is generated by grounding through a metal shaft. This is a conductive path of a secondary transfer bias supplied from the part via the secondary transfer roller 121. As described above, by providing the driving roller 82 with a rubber layer having high friction and shock absorption, the sheet enters the secondary transfer position TR2 where the driving roller 82 and the secondary transfer roller 121 are in contact with each other. It is difficult to transmit the impact at the time of the transfer to the transfer belt 81, and deterioration of image quality can be prevented. The secondary transfer roller 121 is driven so as to be separated from or in contact with the transfer belt 81 by a secondary transfer roller driving mechanism (not shown). The image transferred to the transfer belt 81 is secondarily transferred to the sheet fed to the secondary transfer position TR2.

  The fixing unit 13 includes a heating roller 131 that includes a heating element such as a halogen heater and is rotatable, and a pressure unit 132 that presses and biases the heating roller 131. The pressure unit 132 includes two rollers 1321 and 1322 and a pressure belt 1323 stretched between them.

  The sheet on which the image has been secondarily transferred is guided by the sheet guide member 15 to a nip portion formed by the heating roller 131 and the pressure belt 1323 of the pressure portion 132, and the image is heated at a predetermined temperature in the nip portion. It is fixed.

  By pressing the belt tension surface stretched by the two rollers 1321 and 1322 on the surface of the pressure belt 1323 against the peripheral surface of the heating roller 131, the nip portion formed by the heating roller 131 and the pressure belt 1323 is wide. It is configured to be taken. The sheet subjected to the fixing process is conveyed to a paper discharge tray 4 provided on the upper surface of the housing body 3.

  In the image forming apparatus 1, a cleaner unit 71 is disposed to face the blade facing roller 83. The cleaner unit 71 includes a cleaner blade 711 and a waste toner box 713. The cleaner blade 711 removes foreign matters such as toner and paper dust remaining on the transfer belt 81 after the secondary transfer by abutting the tip of the cleaner blade 711 with the blade facing roller 83 via the transfer belt 81. . The foreign matter removed in this way is collected in a waste toner box 713. Further, the cleaner blade 711 and the waste toner box 713 are integrally formed with the blade facing roller 83.

  Next, the line head 29 in the present embodiment will be described in detail with reference to the drawings. FIG. 3 is a perspective view showing an outline of the line head 29 according to the present embodiment. FIG. 4 is a schematic sectional view of the line head 29. 1 and 3, the line head 29 includes a light emitting element group 295 including a plurality of light emitting elements 2951 arranged in the axial direction of the photosensitive drum 21 (direction perpendicular to the paper surface of FIG. 1). It is spaced from the photosensitive drum 21. The light emitting element 2951 can irradiate light onto the surface 211 that is the surface to be scanned of the photosensitive drum 21 charged by the charging unit 23 to form an electrostatic latent image on the surface 211.

  In FIG. 3, the line head 29 in the present embodiment is positioned with respect to the photosensitive drum 21 with the main scanning direction XX as the long direction and the sub scanning direction YY as the short direction.

  3 and 4, the line head 29 includes a transparent substrate 293 having a plurality of light emitting element groups 295 formed on the back surface, a light shielding member 297 disposed on the surface of the substrate 293, and a substrate 293 with the light shielding member 297 interposed therebetween. An elongated plate-like first lens array 298 facing the surface of the substrate, an elongated plate-like second lens array 299 disposed so as to face the first lens array 298, a substrate 293, and a first lens The first spacer 291 is disposed between the array 298 and the second spacer 292 is disposed between the first lens array 298 and the second lens array 299.

  The lens arrays 298, 299, the light shielding member 297, and the substrate 293 have an elongated rectangular shape with the main scanning direction XX as a longitudinal direction.

  As shown in FIG. 3, the plurality of light emitting element groups 295 are two-dimensionally and discretely arranged on the back surface of the substrate 293 so as to be separated from each other by a predetermined distance in the main scanning direction XX and the sub-scanning direction YY. . Here, each of the plurality of light emitting element groups 295 is configured by arranging a plurality of light emitting elements 2951 in two rows as shown in a circled portion in FIG.

  In the present embodiment, an organic EL element (OLED) is used as the light emitting element. That is, in this embodiment, the organic EL element is disposed as the light emitting element 2951 on the back surface of the substrate 293. A light beam emitted from each of the plurality of light emitting elements 2951 toward the photosensitive drum 21 passes through the substrate 293 and travels toward the light shielding member 297. An LED element can also be used as the light emitting element.

  3 and 4, a urethane light shielding member 297 having a porous entire surface has a plurality of light guide holes 2971 so as to correspond to the plurality of light emitting element groups 295 on a one-to-one basis. Is drilled. The light guide hole 2971 is formed as a substantially cylindrical hole penetrating the light shielding member 297 so as to be parallel to the normal line of the surface of the substrate 293. Although a resin layer or the like may be provided on at least one surface of the light shielding member 297, the inner peripheral surface of the light guide hole 2971 remains porous even in that case.

  The first lens array 298 includes a glass substrate 2981 and a plurality of lens pairs configured by two lenses 2982 and 2983 arranged in a one-to-one correspondence so as to sandwich the glass substrate 2981. These lenses 2982 and 2983 can be formed of resin. The two lenses 2982 and 2983 constituting the lens pair share a common optical axis.

  The second lens array 299 includes a glass substrate 2991 and a plurality of one lens 2992 disposed on one surface (light source side) of the glass substrate 2991. However, lenses may be provided on both sides. The first lens array 298 and the second lens array 299 can be manufactured by the same manufacturing method as the lens block as an intermediate product described in, for example, Japanese Patent Application Laid-Open No. 2010-054810. In the first lens array 298 and the second lens array 299, it is preferable to form a black film around the lens.

  In FIG. 4, lenses 2982, 2983, and 2992 having a common optical axis are arranged so as to correspond to the plurality of light emitting element groups 295 on a one-to-one basis.

  FIG. 5 is a diagram showing an arrangement of a plurality of light emitting element groups 295. As shown in FIG. In the present embodiment, one light emitting element group 295 is configured by arranging two light emitting element rows L2951 arranged in the main scanning direction XX at predetermined intervals and arranging two light emitting element rows L2951 in the sub scanning direction YY. Yes. That is, the eight light emitting elements 2951 form a light emitting element group 295 so as to fit in the center of the hole 2971 of the light shielding member 297 indicated by the two-dot chain line in FIG. The plurality of light emitting element groups 295 are arranged as follows.

  The light emitting element group 295 is two-dimensionally arranged such that three light emitting element group rows L295 (group row) configured by arranging a predetermined number (two or more) of light emitting element groups 295 in the main scanning direction XX are arranged in the sub scanning direction YY. Is arranged. Further, all the light emitting element groups 295 are arranged at different main scanning direction positions. Further, the plurality of light emitting element groups 295 are arranged so that the sub scanning direction positions of the light emitting element groups (for example, the light emitting element group 295C1 and the light emitting element group 295B1) whose main scanning direction positions are adjacent to each other are different. The main scanning direction position and the sub scanning direction position mean the main scanning direction component and the sub scanning direction component at the position of interest, respectively.

  Corresponding to the arrangement of the light emitting element groups 295, light guide holes 2971 are arranged in the light shielding member 297, and lenses 2982, 2983, and 2992 having a common optical axis are arranged. That is, in this embodiment, the center position of the light emitting element group 295, the center axis of the light guide hole 2971, and the optical axes of the lenses 2982, 2983, and 2992 are configured to substantially coincide with each other.

  As shown in FIG. 4, the light emitted from the light emitting elements 2951 belonging to each light emitting element group 295 passes through the light guide holes 2971 corresponding to the light emitting element groups 295 and corresponds to the lens arrays 298 and 299. The light is guided to lenses 2982, 2983, and 2992, and images are formed as spots on the surface 211 of the photosensitive drum 21 by the lenses 2982, 2983, and 2992. At this time, the light shielding member 297 shields the light beam emitted from one light emitting element group 295 so as not to enter the lenses 2982, 2983, and 2992 corresponding to another light emitting element group 295 (as indicated by hatching in FIG. 3). ) Has a function. Furthermore, according to the present embodiment, since the inner peripheral surface of the light guide hole 2971 is porous, the inner peripheral surface when light emitted from the light emitting element 2951 passes through the light guide hole 2971. Reflection as shown by the dotted line is suppressed even when incident on the light, and stray light can be suppressed.

  Next, a method of manufacturing the light shielding member 297 will be described with reference to FIGS. First, a sheet-like urethane foam material UF having a thickness of 1 mm is prepared. The thickness of the urethane foam material UF can vary depending on the distance between the substrate and the lens array and the size of the light guide hole. A double-sided tape TP from which the anti-adhesion film has been peeled off on only one surface is attached to the surface opposite to the surface processed by the urethane foam material UF. However, when one side of the urethane foam material UF is not porous, it is preferable to attach the double-sided tape TP to this side.

  In FIG. 6, a urethane foam material UF is placed on a table (not shown), and a first pinnacle die PD1 is placed above the urethane foam material UF. The first pinnacle die PD1 made of metal has a rectangular shape, and has a straight blade PD1a protruding over the entire circumference on the surface of the urethane foam material UF side, and an inner side surrounded by the sharp straight blade PD1a. Has a cylindrical first punch PD1b protruding in a staggered manner.

  When the first pinnacle die PD1 is vigorously approached from above the urethane foam material UF, the urethane foam material UF is cut into a rectangular shape by the straight blade PD1a as shown by the dotted line in FIG. The outer shape of the member 297 is cut out with high accuracy. At the same time, the urethane foam material UF is punched into a circular shape by the first punch PD1b, and holes UFa are formed at a pitch of 2p. (See FIG. 7). Since the urethane foam material UF is excellent in workability compared to a metal material or the like, even if the shear length is long, it can be easily punched using a pinnacle die.

  Next, as shown in FIG. 7, the urethane foam material UF is placed on a table (not shown), and the second pinnacle die PD2 is placed above the urethane foam material UF. The second pinnacle die PD2 made of metal has a rectangular shape like the first pinnacle die PD1, but does not have a straight blade. The second pinnacle die PD2 has a second punch PD2b which is in a zigzag shape but is arranged in a complementary arrangement with the holes UFa and has a cylindrical shape with the same diameter as the first punch PD1a.

  When the second pinnacle die PD2 is positioned with respect to the urethane foam material UF with vigorous approach, the urethane foam material UF is punched into a circle by the second punch PD2b as shown by the dotted line in FIG. The hole UFb is formed just between the holes UFa. The light shielding member 297 is formed by the above process. The light guide holes 2971 are formed by holes UFa and UFb arranged at an equal pitch.

  The light shielding member 297 used in this embodiment has a narrow interval between adjacent light guide holes 2971, and therefore, when processed with a single punch, the adjacent holes cannot be formed accurately. There is a fear. Therefore, by using pinnacle dies PD1 and PD2 having punches (hole punching portions) PD1b and PD2b having a pitch 2p, light guide holes 2971 having a half pitch p are formed through two punching steps. Thus, processing with high accuracy can be performed.

  Next, the anti-adhesion film is peeled off from the double-sided tape TP attached to one side of the light shielding member 297 and attached to the substrate 293 in a positioned state. Since the urethane foam material is porous and can be expanded and contracted, when the entire light shielding member 297 is attached to the substrate 293 by the double-sided tape TP, the substrate 293 follows the substrate 293 when it thermally expands. Therefore, the positional relationship between the light emitting element group 295 and the light guide hole 2971 is not likely to be shifted.

  After that, the first spacer array 298 is bonded between the relatively positioned substrate 293 and the first lens array 298, and the relatively positioned first lens array 298 and the second lens are further bonded. The line head 29 is formed by bonding the second spacer 292 between the array 299 and the second spacer 292.

  FIG. 8 is a diagram showing another manufacturing method of the light shielding member 297. In FIG. 8, one end of a strip-like urethane foam material UF wound around the driven shaft FS is drawn out and connected to the periphery of a drive shaft DS connected to a drive source (not shown). A base BS is disposed between the driven shaft FS and the drive shaft DS, and the urethane foam material UF passes through the upper surface thereof. Three punches PT that can move along the normal direction of the base BS are arranged above the base BS. The punch PT is preferably shifted with respect to the moving direction of the urethane foam material UF.

  By rotating the drive shaft DS, the urethane foam material UF passes on the base BS. If the punch PT is moved up and down in synchronization with this, the hole UFa is punched into the urethane foam material UF by the punch PT. It is formed. Thereafter, the light shielding member 297 can be formed by cutting the urethane foam material UF by a predetermined length.

  The present invention is not limited to the embodiments described in the specification, and other embodiments and modifications are apparent to those skilled in the art from the embodiments and ideas described in the present specification. It is. For example, after forming the light guide hole from a non-porous material, a chemical treatment or the like may be applied to the inner peripheral surface of the hole to make it porous. Further, the light shielding member may be attached to the lens array instead of the substrate.

3 Housing body 4 Discharge tray 5 Electrical component box 7 Image forming unit 8 Transfer belt unit 11 Paper feed unit 12 Secondary transfer unit 13 Fixing unit 15 Sheet guide member 21 Photoconductor drum 23 Charging unit 25 Developing unit 27 Photoconductor cleaner 29 Line head 51 Image processing unit 52 Main side communication module 53 Head side communication module 54 Head control module 71 Cleaner unit 77 Paper feed cassette 79 Pickup roller 80 Registration roller pair 81 Transfer belt 82 Drive roller 83 Follow roller 83 Blade facing roller 85Y, 85M 85C, 85K Primary transfer roller 86 Downstream guide roller 121 Secondary transfer roller 131 Heating roller 132 Pressure unit 211 Surface 251 Development roller 291 First spacer 292 Second spacer 293 Substrate 295 Light emission Element group 297 Shielding member 298 First lens array 299 Second lens array 711 Cleaner blade 713 Waste toner box 1321, 1322 Roller 1323 Pressure belt 2951 Light emitting element 2971 Light guide hole 2981 Glass substrate 2982, 2983 Lens 2991 Glass substrate 2992 Lens BS Stand DS Drive shaft EC Engine controller EG Engine section FS Drive shaft HC Head controller YST, MST, CST, KST Image forming station L295 Light emitting element group row L2951 Light emitting element row MC Main controller PD1 First pinnacle die PD1a Straight blade PD1b Punch PD2 Second pinnacle die PD2b Punch PT Punch TP Double-sided tape UF Urethane foam material UFa Hole UFb Hole

Claims (6)

An exposure apparatus for an image forming apparatus,
A plurality of light sources provided on the substrate;
A lens array comprising a plurality of lenses;
A light-shielding member disposed between the substrate and the lens array, and provided with a hole for each lens to pass a light beam emitted from the light source and incident on the lens;
A gap is provided between the light shielding member and the lens array,
An exposure apparatus characterized in that at least the inner peripheral surface of the hole of the light shielding member is porous. The exposure apparatus according to claim 1, wherein the light shielding member is made of a material having a porosity of 45 to 90%. The exposure apparatus according to claim 1, wherein the light shielding member is made of urethane. The light blocking member, an exposure apparatus according to any one of claims 1 to 3, the entire surface is characterized by a porous. In the light-shielding member provided between each of the lenses, a hole is disposed between the substrate and the lens array, and has a hole for passing a light beam emitted from the light source and incident on the lens.
By punching with respect to the plate-like material, the exposure apparatus according to any one of claims 1 to 4, characterized in that to form the hole. The pitch of the hole punching part in the punching die used for the punching process is twice the pitch of the hole of the light shielding member, and by performing the punching process twice while changing the relative position of the hole punching part of the punching die, The exposure apparatus according to claim 5 , wherein the hole is formed.