JP2018128643A - Lens mirror array and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lens mirror array that reduces stray light and has high accuracy in image formation and image acquisition, and an image forming apparatus.SOLUTION: A lens mirror array comprises a plurality of arrayed optical elements including a first lens surface 81 on which light is made incident, a first mirror surface 82 on which light is reflected, a second mirror surface 83 that reflects the reflected light, and a second lens surface 84 that emits the reflected light, where the first lens surface, the first mirror surface, the second mirror surface, and the second lens surface are individually formed symmetrically with respect to a symmetry surface A orthogonal to an arrangement direction of the optical elements. The optical element includes one or more pairs of first light blocking surfaces 85 that are formed at positions across the symmetry surface in the arrangement direction of the optical element while sharing sides with the first mirror surface, one or more pairs of second light blocking surfaces 86 that are individually inclined toward the symmetry surface with respect to the one or more pairs of first light blocking surfaces, and a light blocking layer that is formed over the first light blocking surfaces and the second light blocking surfaces.SELECTED DRAWING: Figure 5

Description

  Embodiments described herein relate generally to a lens mirror array and an image forming apparatus.

  The image forming apparatus is a single-row or multiple-row LED array that is turned on / off in accordance with image data (print data) for printing via optical components (lens mirror arrays) configured in a line. A latent image (electrostatic latent image) is formed on the photosensitive drum by forming an image of the emitted light from the photosensitive drum. The image forming apparatus attaches toner (developer) to a latent image formed on a photosensitive drum, transfers the toner attached to the latent image to a paper sheet, and forms a toner image on the paper sheet. Is fixed to form an image on a paper sheet.

  Further, the image forming apparatus forms an image of reflected light of the light irradiated on the paper sheet on the image sensor configured in one or a plurality of lines through the lens mirror array. The image forming apparatus acquires an image of a paper sheet by reading out charges stored in the image sensor and converting them into digital signals.

  The lens mirror array includes a first lens surface on which light is incident, a first mirror surface that reflects light incident on the first lens surface, and a second mirror surface that reflects light reflected by the first mirror surface. , And a structure in which a plurality of optical elements each having a second lens surface that emits light reflected by the second mirror surface are arranged. Japanese Laid-Open Patent Publication No. 2006-138947 discloses a lens mirror array having a light shielding surface that prevents light incident on a first lens surface of a certain optical element from entering another optical element. Yes.

  The lens mirror array includes a pair of light shielding surfaces arranged along the arrangement direction of the optical elements for each optical element. The pair of light-shielding surfaces are provided at positions that share sides with the first mirror surface.

  The lens mirror array is formed by injection molding. For this reason, a curved surface is formed at the corner of the mold due to the corner R of the tool used when the mold is manufactured. Further, there is a possibility that the resin cannot be filled up to the tip of the edge of the mold at the time of molding. As a result, a curved surface is formed between the light shielding surface of the lens mirror array and the first mirror surface. Therefore, a part of the light incident on the first lens surface is reflected by the curved surface between the light shielding surface and the first mirror surface, so that the second mirror surface of the other optical element (element). Or stray light that reaches the second lens surface. When such stray light is generated, there is a problem that the accuracy of image formation on the paper sheet and the acquisition of the image of the paper sheet is reduced.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a lens mirror array and an image forming apparatus with little stray light and high accuracy in image formation and image acquisition.

  The lens mirror array according to an embodiment includes a first lens surface on which light is incident, a first mirror surface that reflects light incident on the first lens surface, and light reflected by the first mirror surface. A plurality of optical elements each including a second mirror surface that reflects and a second lens surface that emits light reflected by the second mirror surface are arranged, and the first lens surface and the first mirror surface. The second mirror surface and the second lens surface are respectively formed symmetrically with respect to a symmetry plane orthogonal to the arrangement direction of the optical elements, and the optical element includes the optical element One or more pairs of first light-shielding surfaces formed by sharing sides with the first mirror surface at positions sandwiching the symmetry plane in the element arrangement direction, and the one or more pairs of first light-shielding surfaces Each before Comprising a second light shielding surface of more than one pair of inclined symmetrically face, and a light blocking layer formed over the first light-blocking surface and said second light shielding surfaces.

FIG. 1 is a diagram for explaining a configuration example of an image forming apparatus according to the first embodiment. FIG. 2 is a diagram for explaining a configuration example of a part of the image forming apparatus according to the first embodiment. FIG. 3 is a diagram for describing a partial configuration example of the image forming apparatus according to the first embodiment. FIG. 4 is a diagram for explaining a configuration example of the lens mirror array according to the first embodiment. FIG. 5 is a diagram for explaining a configuration example of a part of the lens mirror array according to the first embodiment. FIG. 6 is a diagram for explaining a configuration example of a part of the lens mirror array according to the first embodiment. FIG. 7 is a diagram for explaining a configuration example of a part of the lens mirror array according to the first embodiment. FIG. 8 is a diagram for explaining a configuration example of a part of the lens mirror array according to the first embodiment. FIG. 9 is a diagram for explaining a configuration example of a part of the lens mirror array according to the second embodiment. FIG. 10 is a diagram for explaining another configuration example of a part of the lens mirror array according to the second embodiment.

The image forming apparatus and lens mirror array according to the first embodiment will be described below with reference to the drawings.
First, the image forming apparatus 1 according to the first embodiment will be described. FIG. 1 is an explanatory diagram illustrating a configuration example of an image forming apparatus 1 according to the first embodiment.

  The image forming apparatus 1 is, for example, a solid scanning type printer (for example, an LED printer) that performs various processes such as image formation while conveying a recording medium such as a paper sheet P. In the image forming apparatus 1, the photosensitive drum is charged and turned on / off in accordance with image data (print data) for printing via an optical component (lens mirror array) configured in a line 1 A latent image (electrostatic latent image) is formed on the photosensitive drum by forming an image of the radiated light from the LED array in a row or a plurality of rows on the photosensitive drum. The image forming apparatus 1 also attaches toner (developer) to the latent image formed on the photosensitive drum, transfers the toner attached to the latent image to the paper sheet P, and forms a toner image on the paper sheet P. Form. Further, the image forming apparatus 1 fixes the toner image formed on the paper sheet P by sandwiching the paper sheet P on which the toner image is formed with a fixing roller heated to a high temperature by a heater.

  In addition, the image forming apparatus 1 forms an image of reflected light of the light irradiated on the paper sheet P on the image sensor by the lens mirror array, reads out the electric charge accumulated in the image sensor, and converts it into a digital signal. It also functions as an image reading device that acquires an image of the leaf P.

  The image forming apparatus 1 includes a casing 11, a document table 12, a scanner unit 13, an automatic document conveying unit (ADF) 14, a paper feeding cassette 15, a paper discharge tray 16, an image forming unit 17, a conveying unit 18, and a main control unit. 19 is provided. Furthermore, the image forming apparatus 1 may include an operation I / F that receives an operation input, a communication I / F for communicating with other devices, and the like. The document table 12, the scanner unit 13, and the automatic document feeder (ADF) 14 are components that constitute the image reading apparatus.

  The housing 11 is a main body that holds the document table 12, the scanner unit 13, the ADF 14, the paper feed cassette 15, the paper discharge tray 16, the image forming unit 17, the transport unit 18, and the main control unit 19.

  The document table 12 is a portion on which a paper sheet P as a document is placed. The document table 12 is positioned on a glass plate 21 on which a paper sheet P as a document is placed, and a surface opposite to the placement surface 22 on which the paper sheet P as a document on the glass plate 21 is placed. And a space 23 to be used.

  The ADF 14 is a mechanism for conveying the paper sheet P. The ADF 14 is provided on the document table 12 so as to be opened and closed. The ADF 14 takes in the paper sheet P arranged on the tray, and conveys the paper sheet P thus taken in close contact with the glass plate 21 of the document table 12.

  The scanner unit 13 acquires an image from the paper sheet P. The scanner unit 13 is disposed in a space 23 opposite to the placement surface 22 of the document table 12. FIG. 2 is an explanatory diagram for explaining a configuration example of the scanner unit 13. The scanner unit 13 includes an image sensor 31, a lens mirror array 32, an illumination 33, a light shield 34, a housing 35, and a substrate 36.

  The image sensor 31 is an imaging element in which pixels that convert light into an electrical signal (image signal) are arranged in a line. The arrangement direction of the pixels of the image sensor 31 is referred to as a main scanning direction M1. The image sensor 31 includes, for example, a Charge Coupled Device (CCD), a Complementary Metal Oxide Semiconductor (CMOS), or another imaging device.

  The lens mirror array 32 is an optical component that focuses light from a predetermined reading range on the pixels of the image sensor 31. The reading range of the lens mirror array 32 is a rectangular area on the placement surface 22 of the document table 12. The lens mirror array 32 causes the light reflected by the paper sheet P placed on the placement surface 22 of the document table 12 and transmitted through the glass plate 21 to form an image on the pixels of the image sensor 31. The detailed configuration of the lens mirror array 32 will be described later.

  The illumination 33 irradiates the paper sheet P with light. The illumination 33 includes a light source and a light guide that irradiates the paper sheet P with light from the light source. The illumination 33 irradiates an area including the reading range of the lens mirror array 32 with a light guide from the light emitted from the light source.

  The light blocking body 34 is a member that blocks light. The light shielding body 34 is a member having a surface coated with a light shielding material, for example. The light shield 34 is configured and shaped so as to prevent light from a region other than the reading range of the lens mirror array 32 from entering the lens mirror array 32.

  The housing 35 is a member that supports and positions the image sensor 31, the lens mirror array 32, the illumination 33, the light shielding body 34, and the substrate 36. The housing 35 includes a light shielding unit that shields part of the light emitted from the lens mirror array 32. The light shielding unit shields light that becomes stray light when incident on the image sensor 31 or light emitted from the lens mirror array 32 in a direction not incident on the image sensor 31.

  The board 36 is a component on which an image sensor 31, a signal processing unit that reads out an image signal from the image sensor 31 and performs signal processing on the image signal to acquire an image, a memory that temporarily stores the image, and the like are mounted. .

  When the paper sheet P is placed on the placement surface 22 of the document table 12, the scanner unit 13 is in a sub-scanning direction S 1 that is orthogonal to the main scanning direction M 1 and parallel to the placement surface 22. It is driven by a drive mechanism (not shown). The scanner unit 13 is driven in the sub-scanning direction S <b> 1 and continuously acquires images line by line by the image sensor 31, so that the entire paper sheet P placed on the placement surface 22 of the document table 12. Get the image.

  When the paper sheet P is conveyed by the ADF 14, the scanner unit 13 is driven to a position opposite to the position where the paper sheet P is in close contact by the ADF 14. The scanner unit 13 acquires an entire image of the paper sheet P conveyed by the ADF 14 by acquiring images line by line continuously from the paper sheet P conveyed by the ADF 14 by the image sensor 31.

  The paper feed cassette 15 is a cassette that stores paper sheets P. The paper feed cassette 15 is configured to be able to supply paper sheets P from the outside of the housing 11. For example, the paper feed cassette 15 is configured to be drawable from the housing 11.

  The paper discharge tray 16 is a tray that supports the paper sheets P discharged from the image forming apparatus 1. For example, the paper discharge tray 16 is provided on the upper surface of the housing 11.

  The image forming unit 17 forms an image on the paper sheet P based on the control of the main control unit 19. For example, the image forming unit 17 charges the drum, forms a latent image corresponding to image data for printing (print data) on the charged drum, attaches toner to the latent image formed on the drum, and The toner adhering to is transferred to the paper sheet P and an image is formed on the paper sheet P.

  FIG. 3 is an explanatory diagram for explaining a configuration example of the image forming unit 17. For example, as shown in FIG. 3, the image forming unit 17 includes a drum 41, an exposure device 42, a developing device 43, a transfer belt 44, a pair of transfer rollers 45, and a pair of fixing rollers 46.

  The drum 41 is a photosensitive drum formed in a cylindrical shape. The drum 41 is provided in contact with the transfer belt 44. The surface of the drum 41 is uniformly charged by a charging charger (not shown). The drum 41 is rotated at a constant speed in the rotation direction R by a drive mechanism (not shown).

  The exposure device 42 forms an electrostatic latent image on the charged drum 41. The exposure device 42 forms an electrostatic latent image on the surface of the drum 41 by irradiating light on the surface of the drum 41 with a light emitting element or the like according to print data. As shown in FIG. 3, the exposure device 42 includes a light emitting unit 51, a lens mirror array 52, a protective glass 53, a light shield 54, a housing 55, and a substrate 56.

  The light emitting unit 51 has a configuration in which light emitting elements that emit light according to an electric signal (image signal) are arranged in a line. The arrangement direction of the light emitting elements of the light emitting unit 51 is referred to as a main scanning direction M2. The main scanning direction M2 is a direction orthogonal to the optical axes of the plurality of light emitting elements and parallel to the rotation axis of the drum 41. The main scanning direction M2 may be the same as or different from the main scanning direction M1 of the scanner unit 13 described above. The light emitting element of the light emitting unit 51 emits light having a wavelength capable of forming a latent image on the charged drum 41. For example, the light emitting element is an LED or an OLED that emits divergent light in which each LED emits light or extinguishes according to an image signal.

  The lens mirror array 52 is an optical component that images light emitted from the light emitting elements of the light emitting unit 51 on the surface of the drum 41. The lens mirror array 52 has the same configuration as the lens mirror array 52 provided in the scanner unit 13. The range in which light is imaged by the lens mirror array 52 is a rectangular area on the surface of the drum 41. That is, the lens mirror array 52 forms an image corresponding to light from the plurality of light emitting elements of the light emitting unit 51 in a rectangular region on the surface of the drum 41. The detailed configuration of the lens mirror array 52 will be described later.

  The protective glass 53 is provided between the lens mirror array 52 and the drum 41. The protective glass 53 is glass that protects the lens mirror array 52. The protective glass 53 prevents toner and dust from adhering to the lens mirror array 52.

  The light shield 54 is provided between the lens mirror array 52 and the light emitting unit 51. The light shield 54 is a member that blocks light. The light shielding body 54 is a member whose surface is coated with a light shielding material, for example. The light shield 54 shields part of the light emitted from the light emitting unit 51. For example, the light shield 54 shields light passing through a position away from the optical axis of the light emitting element of the light emitting unit 51 by a predetermined distance or more in a direction orthogonal to the optical axis of the light emitting element.

  The housing 55 is a member that supports and positions the light emitting unit 51, the lens mirror array 52, the protective glass 53, the light shielding body 54, and the substrate 56. The housing 55 includes a light shielding unit that shields part of the light emitted from the lens mirror array 52. The light shielding unit shields light that becomes stray light when incident on the drum 41 or light emitted from the lens mirror array 52 in a direction that does not enter a predetermined imaging range on the drum 41.

  The substrate 56 is a component on which the light emitting unit 51 and a driver for driving the light emitting unit 51 are mounted.

  The exposure device 42 inputs print data to a driver provided on the substrate 56 so that the driver emits light from the light emitting unit 51. The light emitted from the light emitting unit 51 is imaged on the drum 41 by the lens mirror array 52. The exposure device 42 forms a latent image on the drum 41 by continuously imaging light from the light emitting unit 51 on the rotating drum 41.

  The developing device 43 attaches toner (developer) to the electrostatic latent image formed on the drum 41. As a result, the developing device 43 forms a toner image (toner image) on the surface of the drum 41.

  The drum 41, the exposure device 42, and the developing device 43 of the image forming unit 17 are provided for different colors such as cyan, magenta, yellow, and black, for example. In this case, the plurality of developing units 43 hold different color toners.

  The transfer belt 44 is a member for receiving the toner image formed on the surface of the drum 41 and transferring it to the paper sheet P. The transfer belt 44 is moved by the rotation of the roller. The transfer belt 44 receives a toner image formed on the drum 41 at a position in contact with the drum 41, and conveys the received toner image to a pair of transfer rollers 45.

  The pair of transfer rollers 45 is configured to sandwich the transfer belt 44 and the paper sheet P. The pair of transfer rollers 45 transfers the toner image on the transfer belt 44 to the paper sheet P.

  The pair of fixing rollers 46 are configured to sandwich the paper sheet P. The pair of fixing rollers 46 is heated by a heater (not shown). The pair of fixing rollers 46 fixes a toner image formed on the paper sheet P by applying pressure to the sandwiched paper sheet P in a heated state. That is, the pair of fixing rollers 46 forms an image on the paper sheet P by fixing the toner image.

  The transport unit 18 transports the paper sheet P. The transport unit 18 includes a transport path constituted by a plurality of guides and a plurality of rollers, and a sensor that detects a transport position of the paper sheet P by the transport path. The conveyance path is a path along which the paper sheet P is conveyed. The conveyance roller conveys the paper sheet P along the conveyance path by being rotated by a motor that operates based on the control of a conveyance control unit (not shown) that has received a command from the main control unit 19. In addition, some of the plurality of guides are switched by a motor that operates based on the control of the transport control unit, thereby switching the transport path for transporting the paper sheet P.

  For example, as illustrated in FIG. 1, the transport unit 18 includes a take-in roller 61, a paper feed transport path 62, a paper discharge transport path 63, and a reverse transport path 64.

  The take-in roller 61 takes the paper sheet P stored in the paper feed cassette 15 into the paper feed conveyance path 62.

  The paper feed conveyance path 62 is a conveyance path for conveying the paper sheet P taken from the paper feed cassette 15 by the take-in roller 61 to the image forming unit 17.

  The paper discharge conveyance path 63 is a conveyance path for discharging the paper sheet P on which the image is formed by the image forming unit 17 from the housing 11. The paper sheet P discharged by the paper discharge conveyance path 63 is discharged to the paper discharge tray 16.

  The reverse conveyance path 64 is a conveyance path for supplying the paper sheet P to the image forming unit 17 again with the front and back, front and back, etc. of the paper sheet P on which the image is formed by the image forming unit 17 being reversed. .

  The main control unit 19 controls the entire image forming apparatus 1. The main control unit 19 includes a processor such as a CPU and a memory. The main control unit 19 implements various processing functions by the processor executing programs stored in the memory. The main control unit 19 acquires an image from the paper sheet P by controlling the scanner unit 13. The main control unit 19 controls the image forming unit 17 to control the image formation on the paper sheet P. For example, the main control unit 19 inputs print data to the image forming unit 17. The main control unit 19 controls the conveyance of the paper sheet P by controlling the conveyance control unit.

Next, the lens mirror array 32 and the lens mirror array 52 will be described.
4 to 7 are explanatory diagrams for explaining a configuration example of the lens mirror array 32 and the lens mirror array 52. FIG. Since the lens mirror array 32 and the lens mirror array 52 have the same configuration, an example of the lens mirror array 52 used in the exposure device 42 will be described in this example.

  FIG. 4 is a perspective view of the lens mirror array 52. The lens mirror array 52 includes a flange portion 71 that is used when the lens mirror array 52 is attached, and a plurality of optical elements 72 that are arranged along the main scanning direction M2. The lens mirror array 52 is formed by injection molding using a die obtained by performing Ni plating on a die steel blank and processing the Ni layer with a tool having R at the corners. The mold has a nested structure, for example. The plurality of optical elements 72 and the flange portion 71 of the lens mirror array 52 are integrally formed by a nested mold. The lens mirror array 52 is made of, for example, transmissive resin or glass.

  The flange portion 71 is a member provided at both ends of the lens mirror array 52 in the arrangement direction of the optical elements 72. Since the flange portion 71 does not affect the optical performance of the lens mirror array 52, it can be touched by hand when attached to the exposure device 42.

  The optical element 72 has a function of forming incident light on an imaging target. For example, the optical element 72 images light from a plurality of light emitting elements of the light emitting unit 51 in an imaging range.

  FIG. 5 is a diagram showing one optical element 72 cut from the lens mirror array 52. FIG. 6 is an explanatory diagram for explaining light when one optical element 72 is viewed from the main scanning direction M2. FIG. 7 is an explanatory diagram for explaining an example in which the lens mirror array 52 is cut along the CC line of FIG.

  The optical element 72 includes a first lens surface 81, a first mirror surface 82 that reflects light incident on the first lens surface 81, and a second mirror surface that reflects light reflected by the first mirror surface 82. 83, and a second lens surface 84 that emits light reflected by the second mirror surface 83. The first lens surface 81, the first mirror surface 82, the second mirror surface 83, and the second lens surface 84 are surfaces with respect to the symmetry plane A that is a surface orthogonal to the arrangement direction of the optical elements 72. It is configured symmetrically.

  The optical element 72 causes the light from the object point O to form an image at the image formation point F. When the optical element 72 is formed on the lens mirror array 52, the light emitting element of the light emitting unit 51 is located at the object point O, and the surface of the drum 41 is located at the imaging point F. When the optical element 72 is formed on the lens mirror array 32, a rectangular reading area on the placement surface 22 of the document table 12 is positioned at the object point O, and the image sensor 31 is positioned at the image point F. Pixels are located. When the optical element 72 is formed on the lens mirror array 32, the main scanning direction M2 can be read as the main scanning direction M1.

  The first lens surface 81 is a convex lens surface whose surface protrudes outward. The first lens surface 81 forms an intermediate inverted image of incident light. Light from a predetermined object point O is incident on the first lens surface 81. For example, the first lens surface 81 is configured such that light emitted from a plurality of light emitting elements of the light emitting unit 51 is incident thereon. Specifically, the first lens surface 81 is configured such that light emitted from a shipping element disposed within a width of 2 to 3 times the pitch of the optical element 72 is incident thereon.

  The first lens surface 81 is, for example, symmetric with respect to the symmetry plane A and is formed in a free-form surface shape. The first lens surface 81 includes a curvature of the first lens surface 81 when the first lens surface 81 is cut by a surface (for example, a symmetric surface A) orthogonal to the main scanning direction M2, and the first lens surface 81. A surface that includes the direction between the second lens surfaces 84 and the main scanning direction M2 may be a surface that has a different curvature from the first lens surface 81 when the first lens surface 81 is cut. Furthermore, the curvature of the first lens surface 81 when the first lens surface 81 is cut by a surface orthogonal to the main scanning direction M2 may be not constant as long as it is symmetric with respect to the symmetry plane A. Furthermore, the curvature of the first lens surface 81 when the first lens surface 81 is cut by a surface including the direction between the first lens surface 81 and the second lens surface 84 and the main scanning direction M2 is: It may not be constant. Furthermore, the curvature of the first lens surface 81 when the first lens surface 81 is cut along a plane orthogonal to the main scanning direction M2 is symmetric with respect to the symmetry plane A and changes by a predetermined change amount. You may do. Furthermore, the curvature of the first lens surface 81 when the first lens surface 81 is cut by a surface including the direction between the first lens surface 81 and the second lens surface 84 and the main scanning direction M2 is: It may change by a predetermined change amount. Further, the first lens surface 81 may be a spherical surface.

  The first mirror surface 82 reflects the light incident on the first lens surface 81. That is, the first mirror surface 82 reflects the light that is incident on the first lens surface 81 and becomes convergent light, and forms an intermediate inverted image on the downstream side of the reflected optical path. The first mirror surface 82 reflects the light incident on the first lens surface 81 by total reflection or Fresnel reflection. The first mirror surface 82 is formed in a planar shape on one side of the optical element 72 in a direction orthogonal to the main scanning direction M2.

  The second mirror surface 83 reflects the light reflected by the first mirror surface 82. That is, the second mirror surface 83 reflects light that has emerged from the intermediate inverted image formed after being reflected by the first mirror surface 82. The second mirror surface 83 reflects the reflected light reflected by the first mirror surface 82 by total reflection or Fresnel reflection.

  The second mirror surface 83 is formed in, for example, a rectangular shape and is curved inward. For example, the second mirror surface 83 is symmetric with respect to the symmetry plane A and is formed in a free-form surface shape. The second mirror surface 83 has a curvature of the second mirror surface 83 when the second mirror surface 83 is cut by a surface orthogonal to the main scanning direction M2 (for example, the symmetry surface A), and the first lens surface 81. A surface that includes the direction between the second lens surfaces 84 and the main scanning direction M2 may be a surface having a different curvature from that of the second mirror surface 83 when the second mirror surface 83 is cut. Furthermore, the curvature of the second mirror surface 83 when the second mirror surface 83 is cut along a plane orthogonal to the main scanning direction M2 may not be constant as long as it is symmetric with respect to the symmetry plane A. Furthermore, the curvature of the second mirror surface 83 when the first lens surface 81 is cut by a surface including the direction between the first lens surface 81 and the second lens surface 84 and the main scanning direction M2 is: It may not be constant. Furthermore, the curvature of the second mirror surface 83 when the second mirror surface 83 is cut along a plane orthogonal to the main scanning direction M2 is symmetric with respect to the symmetry plane A and changes by a predetermined change amount. You may do. Furthermore, the curvature of the second mirror surface 83 when the second mirror surface 83 is cut by a surface including the direction between the first lens surface 81 and the second lens surface 84 and the main scanning direction M2 is: It may change by a predetermined change amount. Further, the second mirror surface 83 may be a spherical surface. Further, the second mirror surface 83 may be formed in a planar shape, for example. The second mirror surface 83 is formed on the side opposite to the first mirror surface 82 of the optical element 72 in the direction orthogonal to the main scanning direction M2.

  The second lens surface 84 is a convex lens surface whose surface protrudes outward. The second lens surface 84 is combined with the second mirror surface 83 to form an erect image that is an inverted image of the intermediate inverted image formed by the first lens surface 81. The light emitted from the second lens surface 84 is incident on a predetermined imaging point F. For example, the light emitted from the second lens surface 84 is imaged at a predetermined position in the imaging range on the drum 41.

  For example, the second lens surface 84 is symmetric with respect to the symmetry plane A and is formed in a free-form surface shape. The second lens surface 84 includes the curvature of the second lens surface 84 when the second lens surface 84 is cut by a surface orthogonal to the main scanning direction M2 (for example, the symmetry surface A), and the first lens surface 81. A surface that includes the direction between the second lens surfaces 84 and the surface including the main scanning direction M2 may have a different curvature from that of the second lens surface 84 when the second lens surface 84 is cut. Furthermore, the curvature of the second lens surface 84 when the second lens surface 84 is cut along a plane orthogonal to the main scanning direction M2 may not be constant as long as it is symmetric with respect to the symmetry plane A. Furthermore, the curvature of the second lens surface 84 when the second lens surface 84 is cut by a surface including the direction between the first lens surface 81 and the second lens surface 84 and the main scanning direction M2 is as follows. It may not be constant. Furthermore, the curvature of the second lens surface 84 when the second lens surface 84 is cut along a plane orthogonal to the main scanning direction M2 is symmetric with respect to the symmetry plane A and changes by a predetermined change amount. You may do. Furthermore, the curvature of the second lens surface 84 when the second lens surface 84 is cut by a surface including the direction between the first lens surface 81 and the second lens surface 84 and the main scanning direction M2 is as follows. It may change by a predetermined change amount. Further, the second lens surface 84 may be a spherical surface.

  The optical element 72 includes a pair of first light shielding surfaces 85, second light shielding surfaces 86, third light shielding surfaces 87, and concave portions 88 formed on the third light shielding surfaces 87.

  The pair of first light shielding surfaces 85 are provided at positions sandwiching the symmetry plane A in the main scanning direction M2. That is, the pair of first light shielding surfaces 85 are arranged along the main scanning direction M2 at a position away from the symmetry plane A by a predetermined distance. The first light shielding surface 85 shares a side with the first mirror surface 82. The first light blocking surface 85 forms an obtuse angle with the first mirror surface 82 and forms an acute angle with respect to the symmetry plane A toward the incident side.

  Further, as shown in FIG. 7, the first light shielding surface 85 has a highly light shielding ink having substantially the same refractive index as that of the lens mirror array (for example, UV containing a light shielding material such as carbon black or black pigment). A light-shielding layer 89 that shields light and is formed by applying ink. The first light shielding surface 85 includes the light shielding layer 89 to prevent light from being reflected from the first light shielding surface 85 to the inside of the optical element 72 and from being emitted outward.

  Further, by forming the first light shielding surface 85 as described above on each optical element 72, a groove having both sides as the first light shielding surface 85 is formed between the two optical elements 72. . A light shielding layer 89 is also formed on the bottom 92 of the groove. This prevents light from being reflected from the bottom 92 of the groove to the inside of the optical element 72 and from being emitted outward.

  FIG. 7 is a view of the lens mirror array 52 cut along the CC line in FIG. 6 as viewed from a direction parallel to the first mirror surface 82 and perpendicular to the main scanning direction M2. Since the lens mirror array 52 is formed by injection molding as described above, a curved surface is formed in the beam portion. For example, as shown in FIG. 7, a curved surface 90 is formed in the beam portion between the first mirror surface 82 and the first light shielding surface 85.

  When the UV ink before curing covers the entire curved surface 90 and is applied in an amount that reaches the first mirror surface 82, the UV ink may spread on the first mirror surface 82. For this reason, the UV ink is applied in an amount that does not cover the entire surface of the curved surface 90. That is, the light shielding layer 89 is formed in a range that covers at least the entire area of the first light shielding surface 85 and does not reach the entire area of the curved surface 90 in order to prevent the UV ink from adhering to the first mirror surface 82. Further, as shown in FIG. 7, the first light-shielding surface 85 and the first mirror surface 82 are formed so as to form an obtuse angle, so that the lens mirror array 52 can be easily peeled off from the mold. Can do.

  The optical element 72 may further include a fourth light shielding surface 91 that is continuous with the end side of the first mirror surface 82 close to the emission side and forms an obtuse angle with the first mirror surface 82. Similarly to the first light shielding surface 85, UV ink is applied to the fourth light shielding surface 91 to form a light shielding layer 89. The fourth light-shielding surface 91 includes the light-shielding layer 89 so that the light reflected by the first mirror surface 82 and traveling through a position away from the symmetry plane A by a predetermined distance is reflected by the first mirror surface 82 and The light traveling directly to the second lens surface 84 is shielded.

  The second light shielding surface 86 is a surface inclined toward the symmetry plane A with respect to the first light shielding surface. For example, the second light shielding surface 86 is configured as a part of a recess that is recessed from the first light shielding surface 85 in a direction orthogonal to the first light shielding surface 85. That is, the second light shielding surface 86 is configured as a surface having a mountain shape together with the first light shielding surface 85.

  The second light shielding surface 86 may be formed as a flat surface or a curved surface. For example, the second light shielding surface 86 is formed as a curved surface having a curvature in one direction. That is, when the second light shielding surface 86 is cut by a plane parallel to the first mirror surface 82, the second light shielding surface 86 has a predetermined curvature whose center of curvature is located inside the optical element 72 relative to the first light shielding surface 85. It is formed to be an arc. That is, the second light shielding surface 86 is formed in a shape corresponding to a part of a cylindrical shape. Further, when the second light shielding surface 86 is cut along a plane parallel to the first mirror surface 82, the center of curvature is located on the inner side of the optical element 72 with respect to the first light shielding surface 85, and the first light shielding surface 86. It may be formed so as to form an arc with a larger curvature as it approaches the mirror surface 82 side. That is, the second light shielding surface 86 may be formed in a shape corresponding to a part of a truncated cone shape.

  The second light shielding surface 86 is also coated with UV ink in the same manner as the first light shielding surface 85 to form a light shielding layer 89. The second light-shielding surface 86 includes a light-shielding layer 89 to shield light traveling at a position away from the symmetry plane A by a predetermined distance.

  In addition, between the 2nd light-shielding surface 86 and the 4th light-shielding surface 91, for example, it comprises the 1st mirror surface 82 and an obtuse angle, and is comprised as a surface parallel to the 1st light-shielding surface 85. FIG. Further, a light shielding layer 89 may also be provided on this surface. This surface may be any surface as long as it forms an obtuse angle with the first mirror surface 82 and forms an acute angle toward the incident side with respect to the symmetry plane A.

  The third light shielding surface 87 is on the same side as the side on which the first mirror surface 82 of the optical element 72 is provided in the direction orthogonal to the main scanning direction M2, and is a second side than the first mirror surface 82. It is formed on the side close to the lens surface 84. The third light shielding surface 87 is formed in a planar shape, for example. For example, the third light shielding surface 87 is formed from the side opposite to the first mirror surface 82 of the fourth light shielding surface 91 to the second lens surface 84. That is, the third light shielding surface 87 is configured to share a side with the fourth light shielding surface 91. The third light shielding surface 87 is formed so that the surface is continuous from the bottom 92 of the groove formed between the two optical elements 72. Further, the third light shielding surface 87 forms an acute angle toward the second mirror surface 83 with respect to the symmetry plane A between the second mirror surface 83 and the second lens surface 84.

  The third light shielding surface 87 is also coated with UV ink to form a light shielding layer 89. The third light-shielding surface 87 includes the light-shielding layer 89, so that the light that is emitted into the air without being reflected by the first mirror surface 82 is incident on the third light-shielding surface 87 again through the optical element 72. It can prevent entering into the structure to comprise.

  The concave portion 88 is a portion that is recessed from the third light shielding surface 87 in a direction orthogonal to the third light shielding surface 87. That is, the concave portion 88 is provided on the light exit side of the first mirror surface 82 in the direction between the first lens surface 81 and the second lens surface 84.

  The recess 88 is formed between the two optical elements 72 in the main scanning direction M2. That is, the recess 88 is formed across two adjacent optical elements 72. By forming the recesses 88 in the respective optical elements 72 in this way, a fifth light-blocking surface 93 that is a pair of light-blocking surfaces facing each recess 88 is formed.

  The fifth light shielding surface 93 is a surface inclined with respect to the main scanning direction M2. That is, the fifth light shielding surface 93 is a surface that forms an angle with respect to the main scanning direction M2. For example, the fifth light shielding surface 93 is formed in a planar shape.

  For example, the bottom 94 between the two fifth light shielding surfaces 93 of the recess 88 is formed so as to be continuous with the bottom 92 of the groove formed between the two optical elements 72.

  Further, UV ink is applied to each surface of the recess 88 to form a light shielding layer 89. The concave portion 88 shields the light entering the other optical element 72 by the fifth light shielding surface 93 on which the light shielding layer 89 is formed, including a component whose light traveling direction is along the main scanning direction M2.

  FIG. 8 is an explanatory diagram for explaining the optical path of light incident on the lens mirror array 52. For example, light incident on the first lens surface 81 from the object point O along the symmetry plane A of the optical element 72 having the lens mirror array 52 is reflected in the order of the first mirror surface 82 and the second mirror surface 83. Then, the light is emitted from the second lens surface 84 to the imaging point F of the optical element 72.

  In the lens mirror array 52 in which a plurality of optical elements 72 are integrally formed, a part of the light incident from the first lens surface 81 and passing through a position away from the symmetry plane A by a predetermined distance is the first mirror surface 82. And the first light shielding surface 85 may be incident on the curved surface 90 formed in the beam portion. Since the light incident on the curved surface 90 is reflected in the direction according to the inclination of the place where the light hits on the curved surface 90, the reflected light travels in various directions and can become stray light entering the other optical element 72. There is sex.

  However, the optical element 72 includes a second light shielding surface 86 that is inclined toward the symmetry plane A with respect to the first light shielding surface 85. Thereby, the optical element 72 can block part of the light traveling at an angle incident on the curved surface 90, such as light passing through the optical path L1 shown in FIG. As a result, the optical element 72 can reduce stray light.

  In addition, the optical element 72 includes a fifth light shielding surface 93 that is provided on the emission side with respect to the first mirror surface 81 and forms an angle with respect to the main scanning direction M2. As a result, the optical element 72 can block a part of the light that travels at an angle that is reflected by the curved surface 90 and incident on the other optical element 72, such as light passing through the optical path L2 shown in FIG. As a result, the optical element 72 can reduce stray light.

  As described above, the lens mirror array 52 is reflected by the first lens surface 81 on which light is incident, the first mirror surface 82 that reflects the light incident on the first lens surface 81, and the first mirror surface 82. A plurality of optical elements 72 including a second mirror surface 83 that reflects the reflected light and a second lens surface 84 that emits the light reflected by the second mirror surface 83 are arranged. Further, the optical element 72 has the first mirror surface 82 and the side at a position sandwiching the symmetry plane A defined by the first lens surface 81 and the second lens surface 84 in the arrangement direction of the optical elements 72 of the lens mirror array 52. A pair of first light shielding surfaces 85 formed in common, a second light shielding surface 86 inclined toward the symmetry plane A with respect to the first light shielding surface 85, and the first light shielding surface 85 and the second light shielding surface 85. A light shielding layer 89 formed over the light shielding surface 86. With this configuration, the lens mirror array 52 has a part of the light incident on the curved surface 90 formed between the first mirror surface 82 and the first light shielding surface 85 and the light reflected from the curved surface 90. A part can be shielded from light. As a result, the lens mirror array 52 can reduce light that is reflected on the curved surface 90 and becomes stray light.

  Further, the second light shielding surface 86 is formed as an arc of curvature in which a cross section in a plane parallel to the first mirror surface 82 has a center of curvature located on the symmetric surface A side with respect to the first light shielding surface 85. . Thereby, the inclination with respect to the symmetry plane A of the 2nd light-shielding surface 86 can be enlarged. With this configuration, the lens mirror array 52 can block more light incident on the curved surface 90. As a result, the lens mirror array 52 can reduce light that is reflected on the curved surface 90 and becomes stray light.

  Further, the first light shielding surface 85 is configured to form an acute angle toward the incident side with respect to the symmetry plane A. Thereby, the space | interval of a pair of 1st light-shielding surface 85 can be narrowed, so that it becomes near the incident side. As a result, the traveling direction of light incident on the curved surface 90 can be limited. In addition, the area facing the symmetry plane A of the second light shielding surface 86 that is continuous with the first light shielding surface 85 can be increased. As a result, the lens mirror array 52 can reduce light that is reflected on the curved surface 90 and becomes stray light.

  Note that the radius of curvature of the second light shielding surface 86 is between the pair of first light shielding surfaces 85 in the optical element 72 in order to simplify the process of cutting the mold for injection molding the lens mirror array 52. It is desirable that the radius of curvature is 1/8 or more of the widest interval. According to this configuration, a tool having a diameter corresponding to the radius of curvature of the second light shielding surface 86 (for example, a face mill or an end mill) is reciprocated twice in a direction substantially parallel to the symmetry plane A and the first mirror surface 82. A mold structure for injection molding the first light shielding surface 85, the second light shielding surface 86, and the fourth light shielding surface 91 can be formed. That is, the radius of curvature of the second light-shielding surface 86 is configured with a radius of curvature of 1/8 or more of the widest distance between the pair of first light-shielding surfaces 85 in the optical element 72. Can be shortened. Note that the smaller the radius of curvature of the second light shielding surface 86, the greater the effect of shielding stray light compared to the larger one. Therefore, it is desirable that the radius of curvature of the second light shielding surface 86 is not less than 1/8 of the widest distance between the pair of first light shielding surfaces 85 in the optical element 72 and is as small as possible.

  It is further desirable that the radius of curvature of the second light shielding surface 86 is configured with a radius of curvature equal to or greater than ¼ of the widest distance between the pair of first light shielding surfaces 85 in the optical element 72. According to this configuration, a tool having a diameter corresponding to the radius of curvature of the second light shielding surface 86 (for example, a face mill or an end mill) is reciprocated once in a direction substantially parallel to the symmetry plane A and the first mirror surface 82. A mold structure for injection molding the first light shielding surface 85, the second light shielding surface 86, and the fourth light shielding surface 91 can be formed. That is, the processing time of the mold is configured such that the radius of curvature of the second light shielding surface 86 is configured with a radius of curvature of 1/4 or more of the widest distance between the pair of first light shielding surfaces 85 in the optical element 72. Can be further shortened.

  Further, in order to continuously process the surface of the first mirror surface 82, the radius of curvature of the second light shielding surface 86 needs to be less than or equal to half the width of the narrowest portion of the first mirror surface. . If this condition is not satisfied, it is necessary to move the tool away from the mold once before and after the narrow place, move the tool away from the narrow place, and lower it again to the same height. If it does in this way, a level difference will be made in the 1st mirror surface 82, and optical performance will fall.

  The optical element 72 is on the same side as the side on which the first mirror surface 82 is provided of the optical element 72 in the direction orthogonal to the main scanning direction M2, and is a second lens than the first mirror surface 82. A third light shielding surface 87 formed on the side close to the surface 84 is provided. Further, the lens mirror array 52 includes a recess 88 formed to be depressed in a direction orthogonal to the third light shielding surface 87 across two adjacent optical elements 72. The lens mirror array 52 has a fifth light shielding surface 93 that is a pair of light shielding surfaces facing each concave portion 88 and inclined with respect to the main scanning direction M2, and a third light shielding surface 87 and a fifth light shielding surface. And a light shielding layer 89 formed over 93. With this configuration, the lens mirror array 52 can block a part of the light reflected at the curved surface 90 and traveling at an angle incident on the other optical element 72. As a result, the optical element 72 can reduce stray light.

  Further, the concave portion 88 constituting the fifth light shielding surface 93 is formed at a position that extends over the two adjacent optical elements 72 and is separated from the symmetry plane A by a predetermined distance in the arrangement direction of the optical elements 72. For this reason, the light that is not stray light and contributes to the image formation is not blocked by the fifth light blocking surface 93, or the amount blocked is very small.

  Further, the bottom 92 between the two first light shielding surfaces 85 facing each other of the lens mirror array 52 and the bottom 94 of the recess 88 are configured as a continuous surface. That is, the bottom 94 of the recess 88 is formed as a surface continuous with the bottom 92 that is a surface between the two first light shielding surfaces 85 facing each other in the adjacent optical element 72. With this configuration, when UV ink is applied to the light shielding surface 87, the UV ink spreads on the light shielding surface 85 and the bottom 92 without breaks. As a result, it is possible to form a light-shielding film without defects while reducing the number of steps for forming the light-shielding film, and the optical element 72 can reduce stray light.

(Second Embodiment)
In the first embodiment, the optical element 72 has been described as a configuration including the pair of second light shielding surfaces 86 between the first lens surface 81 and the fourth light shielding surface 91. It is not limited to this configuration. Depending on the optical design of the lens mirror array 52, light may enter a wide range of the curved surface 90 and stray light may be generated. Therefore, the optical element 72 is provided with a plurality of pairs of second light shielding surfaces 86 between the first lens surface 81 and the fourth light shielding surface 91, so that the light travels in a direction incident on a wide range of the curved surface 90. Can be shielded from light.

  FIG. 9 and FIG. 10 are diagrams showing a configuration of a part of a lens mirror array in which optical elements having a plurality of pairs of second light shielding surfaces are arranged. FIG. 9 is a diagram illustrating a partial configuration of a lens mirror array 52A including two pairs of second light shielding surfaces 86A. FIG. 10 is a diagram illustrating a partial configuration of a lens mirror array 52B including three pairs of second light shielding surfaces 86B.

  As shown in FIG. 9, the lens mirror array 52A includes a plurality of optical elements 72A arranged in the main scanning direction. The optical element 72A includes a first lens surface 81, a first mirror surface 82, a second mirror surface 83, a second lens surface 84, two pairs of first light shielding surfaces 85A, and two pairs of second elements. 86 A of light shielding surfaces, the 3rd light shielding surface 87, the recessed part 88 formed in the 3rd light shielding surface 87, the 4th light shielding surface 91, and the 5th light shielding surface 93 which is a surface of the recessed part 88 are provided.

  Similarly to the first light shielding surface 85, the two pairs of first light shielding surfaces 85A are provided at positions sandwiching the symmetry surface A in the main scanning direction M2, form an obtuse angle with the first mirror surface 82, and are symmetrical. It is a surface that forms an acute angle with respect to the surface A toward the incident side.

  Similarly to the second light shielding surface 86, the two pairs of second light shielding surfaces 86A are surfaces inclined toward the symmetry plane A with respect to the first light shielding surface 85A.

  The first light-shielding surface 85A, the second light-shielding surface 86A, the first light-shielding surface 85A, and the second light-shielding surface 86A are arranged in this order from the first lens surface 81 toward the fourth light-shielding surface 91. It is continuous. Further, the distance between the paired second light shielding surfaces 86A is formed wider as the distance from the incident side becomes closer.

  As shown in FIG. 10, the lens mirror array 52B includes a plurality of optical elements 72B arranged in the main scanning direction. The optical element 72B includes a first lens surface 81, a first mirror surface 82, a second mirror surface 83, a second lens surface 84, three pairs of first light shielding surfaces 85B, and three pairs of second elements. The light shielding surface 86 </ b> B, the third light shielding surface 87, the concave portion 88 formed in the third light shielding surface 87, the fourth light shielding surface 91, and the fifth light shielding surface 93 which is the surface of the concave portion 88 are provided.

  The three pairs of first light shielding surfaces 85B are provided at positions sandwiching the symmetry surface A in the main scanning direction M2 in the same manner as the first light shielding surface 85 and the first light shielding surface 85A, and the first mirror surface 82 and the first light shielding surface 85B. The surface forms an obtuse angle and forms an acute angle toward the incident side with respect to the symmetry plane A.

  The three pairs of second light shielding surfaces 86B are surfaces inclined toward the symmetry plane A with respect to the first light shielding surface 85B, similarly to the second light shielding surface 86 and the second light shielding surface 86A.

  From the first lens surface 81 toward the fourth light shielding surface 91, the first light shielding surface 85B, the second light shielding surface 86B, the first light shielding surface 85B, the second light shielding surface 86B, and the first light shielding surface 86B are provided. The surfaces are continuous in the order of the light shielding surface 85B and the second light shielding surface 86B. Further, the distance between the paired second light shielding surfaces 86 </ b> B is formed so as to be closer to the incident side.

  According to the above configuration, the lens mirror array 52 can shield the light reflected by the curved surface 90 by the second light shielding surface 86A or the second light shielding surface 86B on the emission side. As a result, the optical element 72 can reduce stray light.

  In the above-described embodiment, the image sensor 31 has been described as configured by arranging pixels that convert light into an electrical signal (image signal) in a line shape, but the present invention is not limited to this configuration. The image sensor 31 may be configured by arranging pixels that convert light into an electric signal (image signal) in a plurality of lines. In this case, the scanner unit 13 includes a plurality of lens mirror arrays 32 corresponding to each column of pixels of the image sensor 31 in order to form light from the reading range on the pixels of each column of the image sensor 31. In addition, the scanner unit 13 includes one lens mirror array 32 that forms an image in an area including pixels in each column of the image sensor 31 in order to form light from the reading range on the pixels in each column of the image sensor 31. You may have. The image sensor 31 may have a configuration in which pixels having sensitivity to light of different wavelengths are arranged for each column. Furthermore, the image sensor 31 may include a configuration in which pixels that are sensitive to light of each color wavelength of red, green, and blue are arranged in a staggered manner over two rows.

  In the above-described embodiment, the light emitting unit 51 is described as being configured by arranging light emitting elements that emit light according to an electric signal (image signal) in a line shape, but the present invention is not limited to this configuration. The light emitting unit 51 may be configured by arranging light emitting elements that emit light according to an electric signal (image signal) in a plurality of lines. In this case, the exposure device 42 includes a plurality of lens mirror arrays 72 corresponding to the respective rows of the light emitting elements of the light emitting unit 51 in order to form the light from each row of the light emitting elements on the surface of the drum 41. Further, the exposure unit 42 forms the light from each row of the light emitting elements on the surface of the drum 41, so that the light from the region including the light emitting elements of each row of the light emitting unit 51 is applied to the surface of the drum 41. One lens mirror array 72 that forms an image may be provided. Further, the light emitting unit 51 may have a configuration in which light emitting elements that emit light having different wavelengths are arranged for each column. Furthermore, the light emitting unit 51 may include a configuration in which light emitting elements that emit light of wavelengths of red, green, and blue are arranged in a staggered manner over two rows.

  In the above embodiment, as an example of an image forming apparatus using a lens mirror array, a printer that forms an image on a paper sheet with toner, and a scanner that reads reflected light from the paper sheet and forms an image; However, the present invention is not limited to this configuration. The lens mirror array may be used for any lens as long as it allows the light from the reading range to be imaged on the imaging target. For example, a lens mirror array is used in a silver halide printing device that forms an image by imaging light from a light emitting unit in which a plurality of OLED light sources emitting different colors are two-dimensionally arranged on the surface of a photosensitive material. May be.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus, 11 ... Housing | casing, 12 ... Document stand, 13 ... Scanner part, 14 ... Automatic document conveying part, 15 ... Paper feed cassette, 16 ... Paper discharge tray, 17 ... Image forming part, 18 ... Conveying part , 19 ... main control unit, 21 ... glass plate, 22 ... mounting surface, 31 ... image sensor, 32 ... lens mirror array, 33 ... illumination, 34 ... light shield, 35 ... housing, 36 ... substrate, 41 ... drum , 42 ... exposure unit, 43 ... developing unit, 44 ... transfer belt, 45 ... transfer roller, 46 ... fixing roller, 51 ... light emitting section, 52 ... lens mirror array, 53 ... protective glass, 54 ... shielding member, 55 ... housing 56, substrate, 61 ... take-in roller, 62 ... paper feed conveyance path, 63 ... paper discharge conveyance path, 64 ... reverse conveyance path, 71 ... flange portion, 72 ... optical element, 81 ... first lens surface, 82 ... 1st mirror surface, 83 ... 2nd mirror surface 84 ... second lens surface, 85 ... first light shielding surface, 86 ... second light shielding surface, 87 ... third light shielding surface, 88 ... concave, 89 ... light shielding layer, 90 ... curved surface, 91 ... fourth Light-shielding surface, 92 ... bottom, 93 ... fifth light-shielding surface, 94 ... bottom.

Claims (5)

A first lens surface on which light is incident; a first mirror surface that reflects light incident on the first lens surface; a second mirror surface that reflects light reflected by the first mirror surface; A plurality of optical elements each having a second lens surface that emits light reflected by the second mirror surface are arranged, and the first lens surface, the first mirror surface, the second mirror surface, and the The second lens surface is a lens mirror array formed symmetrically with respect to a symmetry plane orthogonal to the arrangement direction of the optical elements,
The optical element is
A pair of first light-shielding surfaces formed by sharing a side with the first mirror surface at a position sandwiching the symmetry plane in the arrangement direction of the optical elements;
One or more pairs of second light shielding surfaces inclined toward the symmetry plane with respect to the one or more pairs of first light shielding surfaces;
A light shielding layer formed over the first light shielding surface and the second light shielding surface;
A lens mirror array comprising:   The cross section of the second light-shielding surface in a plane parallel to the first mirror surface forms an arc of curvature in which the center of curvature is located closer to the symmetry plane than the first light-shielding surface. Lens mirror array.   3. The lens mirror array according to claim 2, wherein a radius of curvature of the second light shielding surface is equal to or less than half of a width of a narrowest portion of the first mirror surface in the optical element. A light emitting unit comprising a plurality of light emitting elements that emit light;
A first lens surface on which light from the light emitting element is incident; a first mirror surface that reflects light incident on the first lens surface; and a second that reflects light reflected by the first mirror surface. A plurality of optical elements each including a mirror surface and a second lens surface that forms an image of light reflected by the second mirror surface on a surface to be imaged, and the first lens surface and the first lens surface are arranged. A lens mirror array in which a mirror surface, the second mirror surface, and the second lens surface are formed symmetrically with respect to a symmetry plane orthogonal to the arrangement direction of the optical elements;
With
The optical element is
A pair of first light-shielding surfaces formed by sharing a side with the first mirror surface at a position sandwiching the symmetry plane in the arrangement direction of the optical elements;
One or more pairs of second light shielding surfaces inclined toward the symmetry plane with respect to the one or more pairs of first light shielding surfaces;
A light shielding layer formed over the first light shielding surface and the second light shielding surface;
An image forming apparatus comprising: Illumination that irradiates light to a rectangular reading range in a document table on which paper sheets are placed;
An image sensor in which pixels that form an image by converting light into an electrical signal are arranged in a line;
A first lens surface on which light from the reading range is incident, a first mirror surface that reflects light incident on the first lens surface, and a second that reflects light reflected by the first mirror surface A plurality of optical elements including a mirror surface and a second lens surface that forms an image of light reflected by the second mirror surface on a pixel of the image sensor, and the first lens surface and the first lens surface are arranged. A lens mirror array in which a mirror surface, the second mirror surface, and the second lens surface are formed symmetrically with respect to a symmetry plane orthogonal to the arrangement direction of the optical elements;
With
The optical element is
A pair of first light-shielding surfaces formed by sharing a side with the first mirror surface at a position sandwiching the symmetry plane in the arrangement direction of the optical elements;
One or more pairs of second light shielding surfaces inclined toward the symmetry plane with respect to the one or more pairs of first light shielding surfaces;
A light shielding layer formed over the first light shielding surface and the second light shielding surface;
An image forming apparatus comprising: