JP2006082450A - Position adjusting method of line head and its position adjuster - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for adjusting the position of a line head with reference to a lens array, and to provide a position adjuster. <P>SOLUTION: Position of the fiber surface 68a of a rod lens is photographed by means of a CCD camera 90 through an alignment mark formed on a glass substrate 62 mounted on a case 60, and the glass substrate 62. Based on a movement amount calculated from positional information recognized by the CCD camera 90, the glass substrate 62 is moved and set in the case 60 such that the axes of a lens array and the glass substrate 62 are aligned. Both positions are displayed on a display, positional gap between the axes of a rod lens array 65 and a light emitting section 63 is recognized, if any, and then adjusting pins 81 and 82 are moved thus adjusting alignment finely. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a line head position adjusting method and a position adjusting apparatus for detecting a positional deviation of a light emitting element with respect to an optical system and adjusting the position in a line head using a light emitting element such as an organic EL element. .

  In a tandem or rotary image forming apparatus, a method of providing a scanning optical system as an exposure device and a method of using a light emitting element array are known. In the method using the light emitting element array, it is necessary to align the light emitting element and the lens. For example, Patent Document 1 describes an example in which a mark for indicating the center position of a lens is provided on a lens holder for positioning an image array having a plurality of light emitters and a monocular lens. Japanese Patent Application Laid-Open No. H10-228688 describes that the total light amount distribution is measured while causing all the light emitting elements to emit light, and the lens array position is adjusted.

JP-A-7-186444 Japanese Patent Laid-Open No. 10-16291

  In the case of using such an optical system, the imaging optical system of the line head is generally an equal-magnification optical system using a rod lens array having two rows of rod lenses as shown in the explanatory diagram of FIG. Used. In FIG. 12, 84 and 84 are rod lenses arranged in two rows. In this rod lens array, the center line of the rod lens array parallel to the main scanning direction needs to coincide with the position of the light emitting element in the sub scanning direction, but this position may be shifted.

  In FIG. L is the center line of the rod lens array, and A is the position of the light emitting element. An example in which the position of the light emitting element is shifted from the center line C.I. An example of deviation from L by 0.2 mm is shown. As described above, when the position of the light emitting element is deviated from the center line of the rod lens array, the light amount varies. FIG. 13A is a characteristic diagram showing the light amount variation in the main scanning direction, and FIG. 13B is a characteristic diagram showing the light amount distribution data in the sub-scanning direction. As shown in FIG. 13B, when the position of the light emitting element is shifted in the sub-scanning direction, the variation in the light amount occurs symmetrically with respect to the shift amount.

  In FIG. 12, the diameter of the rod lens is 0.56 mm. In this case, the variation in the amount of light in the main scanning direction in FIG. 13A is that when the deviation between the position of the light emitting element and the center line of the rod lens array is 0, the unevenness of the amount of light as in the characteristic Da is the diameter of the rod lens. It is 0.28 of 1/2. When the amount of deviation between the two is 0.1 mm, the period of unevenness in the amount of light is the sum of 0.28 mm, which is ½ the diameter of the rod lens, and 0.56 mm, which is the diameter, as in the characteristic Db. In this case, the light amount unevenness cycle is twice as long as the deviation amount is zero. When the amount of deviation between the two is 0.2 mm, the period of unevenness in the amount of light is 0.56 mm in diameter of the rod lens as in the characteristic Dc.

  As described above, when the position of the light emitting element deviates from the center line of the rod lens array, the following problem occurs. (1) The period of unevenness in the amount of light passing through the rod lens is doubled, making it easy to recognize the unevenness in the amount of light and making the deterioration of the image quality clear. (2) Unevenness in the amount of light passing through the rod lens increases. (3) The amount of light passing through the rod lens decreases. (4) The imaging performance deteriorates, and the spot diameter increases or varies.

  In a line head using LEDs as described in Patent Document 1 as a conventional light emitting element, an image array is mounted on a substrate to constitute a line head. For this reason, the pixel column of the light emitting unit does not become a straight line due to a mounting error, and it is difficult to align the center line of the lens array for all the light emitting pixels. Furthermore, the light amount unevenness of the light emitting unit itself is larger than the transmitted light amount unevenness of the lens array. In order to correct this, one light emitting element is used based on the light amount after passing through the head, as described in Patent Document 2. It is necessary to perform light amount correction control for one unit to correct both the light amount unevenness of the light emitting unit itself and the transmitted light amount unevenness of the lens array. There is also a problem that the spot diameter cannot be corrected.

  The present invention has been made in view of such problems of the prior art, and its purpose is to detect the positional deviation of the light emitting unit with reference to the lens array and adjust the position of the light emitting unit to a normal position. An object of the present invention is to provide a line head position adjusting method and a position adjusting apparatus.

  In order to achieve the above object, a method of adjusting the position of a line head according to the first embodiment of the present invention includes a step of fixing a lens array to a fixing means, a light emitting section in which a plurality of light emitting elements are arranged, an alignment member, A transparent single substrate formed on the lens array, a step of illuminating the lens array, a step of photographing the lens array and the transparent substrate, and displaying the photographed image Displaying on the means, and the position of the transparent substrate by the first position adjusting means so as to align the position of the alignment member formed on the transparent substrate with the reference position of the lens array displayed on the display means. And a step of adjusting. As described above, the method for adjusting the position of the line head according to the first embodiment of the present invention captures the transparent substrate superimposed on the lens array, displays the captured image on the display means, and observes the display image. The position adjusting unit 1 is operated to adjust the position of the transparent substrate with respect to the lens array. Therefore, the position of the transparent substrate, that is, the position of the light emitting unit can be adjusted with respect to the lens array with high accuracy.

  The line head position adjusting method according to the second embodiment of the present invention includes a step of fixing a lens array to a fixing unit, and a step of illuminating the lens array from an image plane side irradiated with output light of a light emitting unit. A step of photographing the lens array, a step of displaying the photographed lens array image on a display means, a step of setting a reference position from the displayed lens array image, and a plurality of light emitting elements arranged A step of photographing a transparent single substrate on which a light emitting portion and an alignment member are formed, a step of displaying an image of the photographed transparent substrate on the display means, and the lens based on the displayed image of the transparent substrate. A step of setting a comparison position to be compared with a reference position of the array, and observing an image of the display means so that the comparison position of the transparent substrate is superimposed on the reference position of the lens array. Characterized the step of adjusting the position of the transparent substrate by the first position adjustment means, in that it consists of. As described above, in the line head position adjusting method according to the second embodiment of the present invention, the lens array and the transparent substrate are separately photographed separately, and the photographed image is displayed on the display means. A position and a contrast position are set. For this reason, the position of the light emitting unit can be accurately adjusted with respect to the lens array.

  In the line head position adjusting method of the present invention, the first position adjusting means adjusts the position of the transparent substrate in the main scanning direction and the sub-scanning direction. In this way, the position of the light emitting unit is adjusted in both the main scanning direction and the sub-scanning direction, so that it is possible to prevent the occurrence of uneven image quality.

  In the line head position adjusting method according to the present invention, the position of the transparent substrate, the position of which is adjusted by the first position adjusting means, with respect to the lens array is further finely adjusted by the second position adjusting means. And Thus, in addition to the position adjustment by the first position adjustment means, the position adjustment by the second position adjustment means is performed, so that the position adjustment of the transparent substrate with respect to the lens array can be performed with high accuracy.

  In the line head position adjusting method of the present invention, the second position adjusting means adjusts the position of the transparent substrate in the sub-scanning direction. For this reason, the image quality can be improved by preventing the positional deviation of the light emitting portion in the sub-scanning direction.

  The line head position adjusting method of the present invention is characterized in that the alignment member is an alignment mark formed directly on the transparent substrate. Thus, since the alignment mark is directly formed on the transparent substrate together with the light emitting portion, no positional deviation occurs. Therefore, the position of the transparent substrate can be accurately adjusted with respect to the lens array.

  The line head position adjusting method of the present invention is characterized in that the alignment member is a module or a wiring directly formed on the upper surface of the transparent substrate. Thus, since the existing module or wiring is used as the alignment member, the cost can be reduced.

  The line head position adjusting method of the present invention is characterized in that the lens array is provided in a plurality of rows in the sub-scanning direction. For this reason, in a line head having a configuration in which a plurality of lens arrays are provided in the sub-scanning direction, it is possible to prevent image quality unevenness.

  In the line head position adjustment method of the present invention, the reference for position adjustment with respect to the transparent substrate is the center of the fiber diameter of the lens of the lens array displayed on the display means, or its center line. And As described above, the position adjustment reference is set to the center of the fiber diameter of the lens or its center line, so that the transparent substrate can be easily aligned.

  The line head position adjusting method of the present invention is characterized in that the lens array is a rod lens array. Since the rod lens has a short focal length and is advantageous for condensing, it is suitable as an optical system component of the image forming apparatus. For this reason, in a practical line head using a rod lens array, it is possible to prevent displacement of the light emitting portion.

  The line head position adjusting method of the present invention is characterized in that the light emitting element is an organic EL element. Thus, since the organic EL element which can manufacture linearity favorably on a process is used as the light emitting element, the position of the light emitting part can be accurately positioned with respect to the lens array.

  In the line head position adjusting device according to the present invention, a light emitting section in which a plurality of light emitting elements are arranged on a single transparent substrate and an alignment member are formed, and a lens array holding means on which output light from the light emitting section is incident A first position that adjusts the position by moving the transparent substrate in the main scanning direction and the sub-scanning direction. An adjustment unit and an illuminating unit that illuminates the lens array, the lens array is illuminated by the illuminating unit, and the transparent substrate arranged on the lens array is photographed by the photographing unit, and the photographed An image is displayed on the display means, and the first position adjusting means adjusts the position of the alignment member formed on the transparent substrate with reference to the lens array. And adjusting the position relative to the lens array of the transparent substrate. In this way, while observing the position of the lens array and the transparent substrate displayed on the display means, the first position adjustment means moves the transparent substrate in the main scanning direction and the sub-scanning direction, and the position relative to the lens array is determined. It is adjusted. Therefore, it is possible to provide a line head position adjusting device that can adjust the position of the light emitting unit with respect to the lens array with high accuracy.

  Further, the line head position adjusting device of the present invention is a second position adjusting means for finely adjusting the position of the transparent substrate, the position of which is adjusted by the first position adjusting means, with respect to the lens array in the sub-scanning direction. Is provided. As described above, since the second position adjusting means is provided in addition to the first position adjusting means, a line head position adjusting device capable of adjusting the position of the light emitting section with higher accuracy can be obtained.

  In the line head position adjusting device of the present invention, the alignment member is an alignment mark formed directly on both upper surfaces of the transparent substrate. Thus, since the position adjustment of the transparent substrate is performed using the alignment mark provided in the vicinity of the light emitting part, the position of the light emitting part with respect to the lens array can be adjusted without error.

  In the line head position adjusting device of the present invention, the lens array is a rod lens array. Since the rod lens has a short focal length and is advantageous for condensing, it is suitable as an optical system component of the image forming apparatus. For this reason, it is possible to improve the image quality in a practical line head using a rod lens array.

  In the line head position adjusting apparatus of the present invention, the light emitting element is an organic EL element. For this reason, in a line head using an organic EL element, it is possible to prevent the light emitting portion from being displaced and to improve the image quality.

  According to the line head position adjusting method and position adjusting apparatus of the present invention, the position of the light emitting unit can be accurately adjusted with reference to the lens array, and as a result, a line head on which a high-quality image is formed can be obtained. .

  The present invention will be described below with reference to the drawings. FIG. 7 is a vertical side view showing an example of an image forming apparatus using a line head whose position is adjusted according to the present invention. In this embodiment, an intermediate transfer belt is used as the transfer belt. In FIG. 7, an image forming apparatus 1 according to the present embodiment is mounted on a housing body 2, a first opening / closing member 3 that can be freely opened and closed on the front surface of the housing body 2, and on an upper surface of the housing body 2. And a second opening / closing member 4 (also serving as a paper discharge tray). Further, the first opening / closing member 3 is provided with an opening / closing lid 3 ′ attached to the front surface of the housing body 2 so as to be freely opened and closed.

  In the housing body 2, an electrical component box 5 containing a power circuit board and a control circuit board, an image forming unit 6, a blower fan 7, a transfer belt unit 9, and a paper feeding unit 10 are disposed. In addition, a secondary transfer unit 11, a fixing unit 12, and a recording medium transport unit 13 are disposed in the first opening / closing member 3. The transfer belt unit 9 is disposed below the housing body 2 and is driven to rotate by a drive source (not shown), a driven roller 15 disposed obliquely above the drive roller 14, and the two rollers. An intermediate transfer belt 16 that is stretched between 14 and 15 and driven to circulate in the direction of the arrow shown in the figure, and a cleaning means 17 that comes into contact with and separates from the surface of the intermediate transfer belt 16.

  A primary transfer member 21 composed of a leaf spring electrode is brought into contact with the image carrier 20 of each image forming station Y, M, C, K by its elastic force, and a transfer bias is applied to the primary transfer member 21. ing. A test pattern sensor 18 is installed in the transfer belt unit 9 in the vicinity of the drive roller 14. The image forming unit 6 includes a plurality of (four in this embodiment) image forming stations Y (for yellow), M (for magenta), C (for cyan), and K (for black) that form images of different colors. Each of the image forming stations Y, M, C, and K includes an image carrier 20 including a photosensitive drum, and a charging unit 22 and an image writing unit (line head) disposed around the image carrier 20. ) 23 and developing means 24.

  The image carrier 20 is rotationally driven in the conveyance direction of the intermediate transfer belt 16 as indicated by the arrows in the figure. The charging means 22 is composed of a conductive brush roller connected to a high voltage generation source, and the outer periphery of the brush is opposite to the image bearing member 20 as a photosensitive member at a peripheral speed of 2 to 3 times. The surface of the image carrier 20 is uniformly charged by contact rotation. The image writing means 23 uses an organic EL element array in which organic EL elements are arranged in a line in the axial direction of the image carrier 20. The line head using the organic EL element array has an advantage that the optical path length is shorter and more compact than the laser scanning optical system, can be disposed close to the image carrier 20, and the entire apparatus can be downsized. . In the present embodiment, the image carrier 20, the charging unit 22, and the image writing unit 23 of each image forming station Y, M, C, and K are unitized as one image carrier unit 25.

  Next, details of the developing unit 24 will be described on behalf of the image forming station K. The developing unit 24 includes a toner storage container 26 that stores toner (hatched portion in the drawing), a toner storage part 27 formed in the toner storage container 26, and a toner stirring member disposed in the toner storage part 27. 29, and a partition member 30 that is partitioned and formed on the upper portion of the toner storage portion 27. Further, the toner supply roller 31 disposed above the partition member 30, the blade 32 provided on the partition member 30 and in contact with the toner supply roller 31, and the toner supply roller 31 and the image carrier 20 are in contact with each other. And a regulating blade 34 that is in contact with the developing roller 33.

  The paper feed unit 10 includes a paper feed unit including a paper feed cassette 35 in which the recording media P are stacked and held, and a pickup roller 36 that feeds the recording media P from the paper feed cassette 35 one by one. In the first opening / closing member 3, a registration roller pair 37 that regulates the feeding timing of the recording medium P to the secondary transfer portion, and a secondary transfer unit that is pressed against the drive roller 14 and the intermediate transfer belt 16. A secondary transfer unit 11, a fixing unit 12, a recording medium conveyance unit 13, a paper discharge roller pair 39, and a duplex printing conveyance path 40 are provided.

  The fixing unit 12 includes a heating roller 45 that includes a heating element such as a halogen heater and is rotatable, a pressure roller 46 that presses and biases the heating roller 45, and is swingable on the pressure roller 46. A belt tension member 47 and a heat-resistant belt 49 stretched between the pressure roller 45 and the belt tension member 47. The color image secondarily transferred to the recording medium is fixed to the recording medium at a predetermined temperature at a nip formed by the heating roller 45 and the heat-resistant belt 49.

  FIG. 8 is a schematic perspective view showing the image writing unit 23 in an enlarged manner. The image writing unit 23 places the light emitting unit 63 of the organic EL element array 61 on the glass substrate 62. The light emitting unit 63 is driven by a driving circuit 88 using TFTs formed on the same glass substrate 62. The gradient index rod lens array (SLA) 65 constitutes an imaging optical system, and has a gradient index rod lens 84 arranged in front of the light emitting unit 63. In the present invention, the glass substrate 62 may be referred to as an EL substrate or an EL substrate light emitting array.

  Reference numeral 90 denotes a CCD camera for observing a positional shift between the light emitting unit 63 and the SLA 65. Reference numeral 87b denotes an alignment mark (alignment mark) formed directly on the upper surface of the glass substrate 62 in order to observe the displacement, and the alignment mark 87a is also formed on the other end of the glass substrate 62. Details of the operation of the alignment marks 87a and 87b and the CCD camera 90 will be described later.

FIG. 9 is a cross-sectional view illustrating a configuration example in the vicinity of the light emitting unit 63 of the organic EL light emitting element array 61 illustrated in FIG. 8. The organic EL light emitting element array 61 includes, for example, a staggered driving circuit 88 made of TFT (thin film transistor) made of polysilicon having a thickness of 50 nm for controlling light emission of each light emitting portion 63 on a glass substrate 62 having a thickness of 0.5 mm. Corresponding to each of the two rows of light emitting portions 63 in the arrangement, it is provided outside the margin. An insulating film 72 made of SiO ₂ having a thickness of about 100 nm is formed on the glass substrate 62 except for the contact hole on the drive circuit 88. In addition, an anode 73 made of ITO having a thickness of 150 nm is formed at the position of the light emitting portion 63 so as to be connected to the drive circuit 88 through the contact hole.

Next, another insulating film 74 made of SiO ₂ having a thickness of about 120 nm is formed in a portion corresponding to a position other than the light emitting portion 63, and a thickness in which a hole 76 corresponding to the light emitting portion 63 is formed thereon. A partition wall 75 made of 2 μm polyimide is provided. A hole injection layer 77 having a thickness of 50 nm and a light emitting layer 78 having a thickness of 50 nm are formed in order from the anode 73 side in the hole 76 of the partition wall 75, and the upper surface of the light emitting layer 78, the inner surface of the hole 76, and the partition wall. A cathode first layer 79a made of Ca having a thickness of 100 nm and a cathode second layer 79b made of Al having a thickness of 200 nm are sequentially formed so as to cover the outer surface of 75.

  Then, the light emitting portion 63 of the organic EL light emitting element array 61 is configured by being covered with a cover glass 64 having a thickness of about 1 mm via an inert gas 80 such as nitrogen gas. Light emission from the light emitting unit 63 is performed on the glass substrate 62 side. Various known materials can be used as the material used for the light emitting layer 78 and the material used for the hole injection layer 77, and detailed description thereof is omitted. Such an organic EL light emitting element can be easily manufactured on a glass substrate, and thus the manufacturing cost can be reduced.

  FIG. 10 is an explanatory diagram showing a process for positioning the line head. In FIG. 10A, the rod lens array 65 is inserted into the opening 60a formed at the center of the case 60, and the tip of the rod lens array 65 is locked by the stepped portion 60x provided in the opening 60a. Then, it is fixed to the case 60. In (b), the light emitting portion (not shown) mounted on the glass substrate 62 is sealed with a cover glass 64, the glass substrate 62 is inserted into the case 60, and placed on the step portion 60y formed inside the case 60. Put. When the glass substrate 62 is placed on the stepped portion 60y, the light source 89 is turned on as described with reference to FIGS. 1 and 4, and then the glass substrate 62 stacked on the rod lens array 65 by the CCD camera 90 is turned on. The alignment mark is photographed and the photographed image is displayed on the display device 100. While observing the display image, the X and Y drive handler 96 is used to move the glass substrate 62 in the X direction (sub-scanning direction) and the Y direction (main scanning direction) to perform the first stage position adjustment. Is called. A specific example of the position adjustment of the glass substrate 62 with respect to the reference position of the rod lens array 65 will be described later.

  With the glass substrate 62 placed in the case 60, the CCD camera 90 further photographs the alignment mark and observes the captured image on the display device. The presence / absence of misalignment between the alignment mark formed on the glass substrate 62 and the center line of the rod lens array 65 is confirmed. If necessary, the position adjustment pins 81 and 82 described in FIG. For this reason, the glass substrate 62 whose position has been adjusted in the first stage is finely adjusted in the X direction (sub-scanning direction), and the center line position of the light emitting unit and the center line C.D. A second stage alignment with L is performed. As described above, since the position of the light emitting unit is finely adjusted in the sub-scanning direction, which is greatly affected by image quality deterioration, a high-quality image can be obtained.

  When the position adjustment is completed, (c) the glass substrate 62 is fixed to the case 60 with the adhesive 83. Next, (d) the cover 66 is attached, the cover 66 is pressed by the fixed plate spring 67, and the flange portion 67a formed at the tip of the fixed plate spring 67 is locked to the stepped portion 60z formed outside the case 60. Fix it. The case 60 functions as a holding unit for the rod lens array 65.

  FIG. 11 is a cross-sectional view of the image writing unit 23 in the sub-scanning direction. The image writing means 23 includes an organic EL element array 61 attached facing the rear surface of the gradient index rod lens array 65 in the case 60, and an organic EL light emitting element array 61 in the rear surface of the case 60. And an opaque cover 66 for shielding the light. Further, the cover 66 is pressed against the back surface of the case 60 by the fixed plate spring 67, and the inside of the case 60 is sealed in a light-tight manner. That is, the glass substrate 62 is optically sealed with the case 60 by the fixed plate spring 67. A plurality of fixed leaf springs 67 are provided in the longitudinal direction of the case 60. Reference numeral 91 denotes an image surface formed on the image carrier.

  If a black paint that absorbs ultraviolet rays is applied to the inner surface of the housing (not shown) of the image forming apparatus main body that houses the case 60, the ultraviolet shielding action on the organic EL element array 61 can be more reliably performed. And deterioration of the organic EL light emitting element can be prevented. The case 60 of the image writing means 23 is formed of an opaque member, and the back surface thereof is covered with an opaque cover 66.

  For this reason, the fluorescent lamp and the ultraviolet rays from the sun incident on the back surface of the organic EL element array 61 are prevented from reaching the light emitting part 63 of the organic EL element array 61. Reference numeral 83 denotes an adhesive for fixing the glass substrate 62 to the case 60. In FIG. 11, the position adjustment pins 81 and 82 and the knobs 86 and 87 described in FIG. 1 are not shown for simplicity.

  FIG. 5 is an explanatory diagram showing an example of a process flow for incorporating the rod lens array 65 into the case 60. Next, this process flow will be described. (A) A line head case (indicated by numeral 60 in FIG. 1) is set on a guide plate (not shown) of the position adjusting device. The line head case in this case is set on the guide plate in a state reverse to that in FIG. (B) The rod lens array 65 is set in the case groove (indicated by reference numeral 69 in FIG. 1). (C) Fixing to the case 60 while correcting the warp of the rod lens array 65. In this manner, the rod lens array 65, which serves as a reference when aligning the EL substrate (glass substrate), is fixed.

  FIG. 6 is an explanatory diagram showing an example of an assembly process flow when the EL substrate (glass substrate 62) is assembled into the case 60. FIG. Next, this process flow will be described. (A) The case 60 in which the rod lens array 65 has been incorporated is set on the guide plate (the number 93 in FIG. 4) of the position adjusting device. The position of the case 60 in this case is a position reversed from the state in which the rod lens array described with reference to FIG. 5 is set. Such a reversing mechanism uses appropriate means such as material handling (material handling). (B) The light source 89 in FIG. 1 is turned on, two points in the longitudinal direction (main scanning direction) of the rod lens array 65 are photographed by the CCD camera 90, and the image is recognized by the display device 100 in FIG. (C) Based on the planar image of the rod lens array 65 whose image is recognized by the CCD camera 90, the control unit (not shown) calculates the center line position (reference position) of the rod lens array 65.

  In this calculation, when the rod lenses are arranged in one row as shown in FIG. 2, a line connecting the center point positions of the two rod lenses is obtained as the center line. Also, as shown in FIG. 3, when two rows of rod lenses are arranged, a line connecting the center point positions of the two rod lenses in the upper row and the center point positions of the two rod lenses in the lower row A middle line between the lines connecting the two is obtained as the center line.

  (D) The alignment mark (numbers 87a and 87b shown in FIGS. 2 and 3) of the EL substrate light emitting array (glass substrate 62) or two longitudinal points of the EL substrate light emitting array are photographed with the CCD camera 90, and FIG. The display device 100 recognizes an image. (E) Based on the planar image of the EL substrate light emitting array whose image has been recognized by the CCD camera 90, the control unit (not shown) calculates the center line position (contrast position) of the EL substrate light emitting array.

  (F) The center line (contrast) of the EL substrate light-emitting array 62 is aligned with the center line position (reference position) of the rod lens array 65 fixed to the case 60 by the X and Y drive handler (denoted 96 in FIG. 4). The position of the EL substrate light emitting array 62 is adjusted so as to match the position), and the EL substrate light emitting array 62 is set in the case 60. In this process, the center line position of the rod lens array 65 obtained by calculation is displayed on the display device 100, and the displayed center line position of the rod lens array 65 and the center line of the EL substrate light emitting array 62 are displayed on the display device 100. To match on the screen.

  (G) The position of the EL substrate light emitting array 62 is confirmed in the X direction and the Y direction by the method of the present embodiment, that is, the captured image by the CCD camera 90 and the displayed captured image on the display device. The position adjustment in the X direction is performed by the position adjustment pins 81 and 82 in FIG. (H) When the position adjustment is completed, the EL substrate 62 is fixed to the case 60 with the adhesive 83 (FIG. 11). In the example of FIG. 6, the lens array and the transparent substrate are individually photographed separately, the photographed image is displayed on the display means, and the respective reference position and contrast position are set. For this reason, the position of the light emitting unit can be accurately adjusted with respect to the lens array.

  FIG. 1 is a sectional view in the sub-scanning direction showing a schematic configuration example of a line head whose position is adjusted in the present invention. In FIG. 1, the rod lens array 65 is provided with a fiber 68 (corresponding to the position of the rod lens 84 in FIG. 8), and is slid in the groove 69 of the case 60 and set at a predetermined position. As shown in detail in FIG. 9, the organic EL element array 61 has a light emitting portion 63 formed by laminating an insulating layer 72, an anode 73, a cathode 79, and the like on a glass substrate 62. These electrodes are not shown. Reference numeral 68 a denotes a fiber surface of the rod lens array 65.

  Reference numeral 89 denotes a light source (illuminating means) that illuminates from the rod lens image plane. As illustrated in FIG. 4, the light source 89 is turned on when the center line position of the glass substrate 62 is aligned with the center line position of the rod lens array 65 by the X and Y drive handler 96. For this reason, the CCD camera 90 images the position of the fiber surface 68a of the rod lens that has passed through the glass substrate 62, that is, the lens shape, and displays it on the display device. Further, alignment marks 87a and 87b are formed on the glass substrate 62 placed on the case 60 (FIGS. 2 and 3), and the alignment marks are photographed by the CCD camera 90 and displayed on the display device. Is done. Thus, since the light source 89 is provided on the opposite side of the CCD camera 90 with respect to the glass substrate 62, the CCD camera 90 can clearly confirm the position of the fiber surface 68a by the transmitted light. In the example of FIG. 1, the light source 89 is provided on the opposite side of the CCD camera 90 when the glass substrate 62 is viewed as a reference. In the present invention, the light source 89 can be installed on the same side as the CCD camera 90. Even in such a case, if there is no light shielding member, the position of the fiber surface 68a can be confirmed.

  As will be described with reference to FIG. 4, the position of the glass substrate 62 whose position has been adjusted by the X and Y drive handler 96 (first position adjusting means) is further finely adjusted. At this time, based on the alignment marks 87a and 87b of the glass substrate 62 displayed on the display device 100 and the position of the fiber surface 68a of the rod lens (the center of the fiber diameter or its center line), Whether or not there is a positional deviation between the position and the position of the center line of the light emitting unit 63, that is, the position of the center line of the EL substrate light emitting array (glass substrate) 62 is confirmed. If there is a misalignment between the two, fine adjustment of the alignment is performed.

  At this time, the position of the glass substrate 62 in the sub-scanning direction (X direction) is finely adjusted by the position adjustment pins 81 and 82 provided on the left and right of the case 60. The position adjustment pins 81 and 82 are formed with inclined portions 81a and 82a. The adjustment pins 81 and 82 are moved from the outside of the case 60 using the knobs 86 and 87 to align the center line of the EL substrate light emitting array 62 with the center line of the rod lens array. Since the adjustment pins 81 and 82 are formed with the inclined portions 81a and 82a, the position of the glass substrate 62 in the sub-scanning direction can be adjusted with high accuracy. Thus, the position adjustment pins 81 and 82 function as the second position adjustment means of the line head. As described above, in the present invention, since the position adjusting pins 81 and 82 of the second position adjusting means are provided in addition to the X and Y driving handlers 91 which are the first position adjusting means, more accurate. The position of the glass substrate, that is, the position of the light emitting portion with respect to the rod lens array can be adjusted.

  2 and 3 are plan views showing examples of arrangement of the organic EL element array 61 and the rod lens array 65. FIG. FIG. 2 is an example in which one row of rod lenses 84 is arranged in the rod lens array 65, and FIG. 3 is an example in which two rows of rod lenses 84 a and 84 b are arranged in the rod lens array 65. The present invention can cope with a case where the rod lens array 65 is arranged in one row and a case where the rod lens array 65 is arranged in two rows. 2 and 3, the light emitting units 63 are arranged in two rows in the sub-scanning direction. Further, alignment marks 87 a and 87 b are formed on both ends of the glass substrate 62. The light emitting units 63 are not limited to two rows, and a plurality of rows can be arranged in the sub-scanning direction.

  Since the alignment marks 87a and 87b can be formed in the same process as the light emitting element by, for example, a photolithography technique, the processing process when providing the alignment member on the glass substrate is simplified, and the cost can be reduced. Since the alignment marks 87a and 87b are directly formed on the glass substrate 62 together with the light emitting portion 63, no positional deviation occurs. For this reason, the position of the glass substrate 62 can be accurately adjusted with respect to the rod lens array 65. In the example of FIGS. 2 and 3, the alignment marks 87 a and 87 b are formed on the illustrated surface side of the glass substrate 62, but may be formed on the opposite surface of the glass substrate 62.

  FIG. 4 is an explanatory diagram showing a schematic configuration of the position adjusting device of the present invention. In FIG. 4, reference numeral 96 denotes an X and Y drive handler, which has a horizontal beam 96a and a vertical beam 96b. A fixing plate 95c is attached to the vertical beam 96b, and the EL substrate suction jig 94 is moved in the vertical direction (Z direction) by the guide rods 95a and 95b. The CCD camera 90 reciprocates in the horizontal direction (Y direction, main scanning direction) and the vertical direction (X direction, sub-scanning direction) by the X and Y drive handler 96 to position the EL substrate relative to the rod lens array. adjust. Reference numeral 93 denotes a guide plate of the case 60, and the rod lens array 65 is set as described in the flow (a) of FIG. Thus, the case 60 functions as a fixing means for the rod lens array 65.

  An EL substrate (glass substrate on which an organic EL element is formed) 62 placed on the guide plate 92 of the EL substrate is sucked by the EL substrate suction jig 94 of the X and Y drive handler 91. When the X and Y drive handler 91 moves in the X direction and then in the Y direction, the EL substrate moves in the arrow P direction and reaches the position of the case 60 in which the rod lens array is incorporated. Next, the light source 89 in FIG. 1 is turned on.

  In this state, the X and Y drive handler 91 moves the CCD camera 90 above the EL substrate 62 to capture a planar image of the EL substrate 62 that is arranged on the rod lens array 65. At this time, the CCD camera 90 recognizes the lens shape of the rod lens array 65 and the alignment mark formed on the EL substrate by the transmitted light or reflected light of the EL substrate. The image taken by the CCD camera 90 is displayed on the display device 100, and the X and Y drive handler 96 is moved so that the center line position of the EL substrate 62 overlaps the center line of the rod lens array as described above. When the alignment is completed, the EL substrate 62 is placed on the case 60. The X and Y drive handler 96 functions as a first position adjusting unit for the line head. In the example of FIG. 4, the EL substrate 62 is placed on the rod lens array 65 by the X and Y drive handler 96, and an image photographed from the image plane side by the CCD camera 90 is displayed on the display device 100. In the present invention, as described with reference to FIG. 6, the rod lens array 65 and the EL substrate 62 are individually photographed by the CCD camera 90 from the imaging plane side, and the photographed image is displayed on the display device 100. You can also.

  2 and 3, the alignment marks 87a and 87b are formed on both ends of the glass substrate 62. However, instead of using the alignment marks, components (modules) formed in advance on the glass substrate 62 are used. It is also conceivable to apply wiring (circuit pattern) for alignment. For example, when the cathode 79 and the partition wall 75 described with reference to FIG. 9 are used, it is not necessary to form the alignment marks 87a and 87b, and the cost can be reduced. Since such modules and wiring are also formed directly on the glass substrate 62 together with the light emitting portion 63, no positional deviation occurs. Therefore, even when the module or wiring is used, the position of the glass substrate 62 can be adjusted with respect to the rod lens array 65 with high accuracy.

  2 and 3, the alignment marks 87a and 87b have a cross shape. However, the alignment marks 87a and 87b can be appropriately set to be linear, circular, rectangular, or the like. Moreover, although the organic EL element was demonstrated to the example as a light emitting element formed in a glass substrate, the light emitting element of this invention is not limited to an organic EL element. For example, the present invention can be applied to a line head using a light emitting element of another form such as an inorganic EL element.

  The line head position adjusting method and position adjusting apparatus according to the present invention have been described based on several embodiments. However, the present invention is not limited to these embodiments, and various modifications are possible.

It is sectional drawing which shows the example of the line head applied to this invention. It is a top view of a glass substrate. It is a top view of a glass substrate. It is explanatory drawing which shows the example of the position adjustment apparatus of this invention. It is a process flow figure of lens array incorporation. It is a process flow figure of EL substrate incorporation. 1 is a longitudinal side view of an image forming apparatus in which a line head of the present invention is used. It is a schematic perspective view which expands and shows an image writing means. It is sectional drawing which shows the structural example of the light emission part vicinity. It is explanatory drawing which shows the example of positioning of a glass substrate. It is sectional drawing which shows the example which fixed the glass substrate. It is explanatory drawing which shows the example of the position shift of a light emission part. It is a characteristic view which shows light quantity variation.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus, 16 ... Intermediate transfer belt, 20 ... Image carrier, 23 ... Image writing means (line head), 61 ... Organic EL element array, 62 ... Glass substrate (EL substrate), 63... Light emitting part, 64 .. Cover glass, 65... Refraction index distribution type rod lens array (SLA), 81, 82. Distributed rod lens, 87a, 87b ... alignment mark (alignment mark), 88 ... drive circuit, 89 ... light source, 90 ... CCD camera, 96 ... X, Y drive handler, 100 ... Display devices

Claims (16)

A step of fixing the lens array to the fixing means, a step of arranging a transparent single substrate on which the light emitting section in which a plurality of light emitting elements are arranged and an alignment member are superimposed on the lens array, and illuminating the lens array A step of photographing the lens array and the transparent substrate, a step of displaying the photographed image on a display means, and a reference position of the lens array displayed on the display means on the transparent substrate. And a step of adjusting the position of the transparent substrate by a first position adjusting means so as to align the position of the formed alignment member. A step of fixing the lens array to the fixing means, a step of illuminating the lens array from the image plane side irradiated with output light of the light emitting unit, a step of photographing the lens array, and a photographed image of the lens array Photographing on a transparent single substrate formed with a step of displaying on a display means, a step of setting a reference position from the displayed image of the lens array, and a light emitting portion in which a plurality of light emitting elements are arranged and an alignment member A step of displaying a photographed image of the transparent substrate on the display means, a step of setting a contrast position to be compared with a reference position of the lens array from the displayed image of the transparent substrate, and the display Observing an image of the means, and adjusting the position of the transparent substrate by the first position adjusting means so that the contrast position of the transparent substrate overlaps the reference position of the lens array , Characterized by comprising the method for adjusting position of the line head. The line head position adjusting method according to claim 1, wherein the first position adjusting unit adjusts the position of the transparent substrate in a main scanning direction and a sub scanning direction. 4. The position of the transparent substrate, the position of which is adjusted by the first position adjusting means, with respect to the lens array, is further finely adjusted by the second position adjusting means. The method for adjusting the position of the line head described in 1. The line head position adjusting method according to claim 4, wherein the second position adjusting unit adjusts the position of the transparent substrate in a sub-scanning direction. The line head position adjustment method according to claim 1, wherein the alignment member is an alignment mark formed directly on the transparent substrate. 6. The line head position adjusting method according to claim 1, wherein the alignment member is a module or a wiring directly formed on the upper surface of the transparent substrate. The line head position adjusting method according to claim 1, wherein the lens array is provided in a plurality of rows in the sub-scanning direction. 9. The position adjustment reference with respect to the transparent substrate is the center of the fiber diameter of the lens of the lens array displayed on the display means or the center line thereof. The method for adjusting the position of the line head described in 1. 10. The line head position adjustment method according to claim 1, wherein the lens array is a rod lens array. The line head position adjusting method according to claim 1, wherein the light emitting element is an organic EL element. In a line head having a lens array holding unit on which a light emitting section in which a plurality of light emitting elements are arranged on a transparent single substrate and an alignment member are formed and the output light of the light emitting section is incident, Imaging means, display means for images taken by the imaging means, first position adjustment means for adjusting the position by moving the transparent substrate in the main scanning direction and the sub-scanning direction, and illumination for illuminating the lens array Means for illuminating the lens array with the illumination means, photographing the lens array and the transparent substrate with the photographing means, displaying the photographed image on the display means, and the first position. By adjusting means, the position of the alignment member formed on the transparent substrate is adjusted to the reference position of the lens array, and the position of the transparent substrate with respect to the lens array is adjusted. Characterized Rukoto, position adjusting device of a line head. The second position adjusting means for finely adjusting the position of the transparent substrate, the position of which has been adjusted by the first position adjusting means, with respect to the lens array is further provided in the sub-scanning direction. The line head position adjusting device as described. 14. The line head position adjusting device according to claim 12, wherein the alignment member is an alignment mark formed directly on both upper surfaces of the transparent substrate. 15. The position adjustment device for a line head according to claim 12, wherein the lens array is a rod lens array. The line head position adjusting apparatus according to claim 12, wherein the light emitting element is an organic EL element.

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