JP2014011195A - Light irradiation device and printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light irradiation device which can achieve down-sizing and cost reduction even of a module where a plurality of devices, each mounting a plurality of light-emitting elements on a substrate, are mounted on a support, and to provide a printer.SOLUTION: The light irradiation device includes first light-emitting element groups 20A arranged corresponding to the width of an object in a cross direction X2 crossing the direction of movement X1 of the object, and second light-emitting element groups 20B arranged in a cross direction X2 while holding the first light-emitting element groups 20A therebetween. In the light-emitting elements 20a, 20b included in the first and second light-emitting element groups 20A, 20B, a plurality of semiconductor layers 22 including a luminous layer are laminated. The light-emitting elements 20a are arranged so that the lamination direction of the semiconductor layer 22 crosses a plane including the direction of movement X1 and the cross direction X2, and the light-emitting elements 20b are arranged so that the lamination direction of the semiconductor layer 22 is in parallel with a plane including the direction of movement X1 and the cross direction X2.

Description

  The present invention relates to a light irradiation device used for light irradiation for curing an ultraviolet curable resin or paint, and a printing apparatus including the light irradiation device.

  2. Description of the Related Art Conventionally, ultraviolet irradiation apparatuses are widely used for the purpose of ultraviolet irradiation for observation of fluorescent reactions in medical and bio fields, sterilization applications, adhesion of electronic components, and curing of ultraviolet curable resins and inks. In particular, the UV light source lamp light source used for curing UV curable resins used for bonding small parts in the field of electronic components, etc., and UV curable ink used for printing, etc. Mercury lamps and metal halide lamps are used.

  In recent years, there has been a strong desire to reduce the global environmental load on a global scale, and there has been an active movement to adopt an ultraviolet light emitting element that can suppress the generation of ozone and a relatively long life as a lamp light source. Yes.

  However, since the illuminance of the ultraviolet light-emitting element is relatively low, for example, as described in Patent Document 1, a device in which a plurality of light-emitting elements are mounted on a single substrate is prepared, thereby improving the effect of the ultraviolet curable ink. Necessary ultraviolet irradiation energy is secured.

  However, in the case of a device having a structure in which a plurality of light emitting elements are mounted on a substrate in this way, it is sufficiently larger than the width of the object to ensure a predetermined ultraviolet irradiation energy for the object to be irradiated with ultraviolet light. A device in which light emitting elements are arranged in a wide width is required, and there is a problem that it is difficult to reduce the size and cost of the device.

JP 2008-244165 A

  The present invention has been made in view of the above problems, and a light irradiation device and a printing apparatus that can achieve downsizing and cost reduction even with a light irradiation device in which a plurality of light emitting elements are mounted on a substrate. The purpose is to provide.

  The light irradiation device of the present invention is a light irradiation device for irradiating light to a relatively moving object, and corresponds to the width of the object in a crossing direction that intersects the moving direction of the object. A first light emitting element group disposed; and a second light emitting element group disposed across the first light emitting element group along the intersecting direction. Each light-emitting element included in the group includes a plurality of semiconductor layers including a light-emitting layer, and each of the light-emitting elements included in the first light-emitting element group moves in the stacking direction of the semiconductor layer. Each light emitting element included in the second light emitting element group includes a plane in which the stacking direction of the semiconductor layers includes the moving direction and the intersecting direction. To be parallel to Characterized in that it is location.

In the light irradiation device of the present invention, in the above configuration, the light emitting elements included in the first and second light emitting element groups are arranged vertically and horizontally in the respective light emitting element groups. The arrangement interval in the crossing direction of the light emitting elements adjacent to each other in the light emitting element included in the light emitting element group and the light emitting element included in the second light emitting element group is included in the first light emitting element group. The light emitting elements are shorter than the arrangement interval in the crossing direction.

  Furthermore, the light irradiation device of the present invention is characterized in that, in the above configuration, the light emitting device further includes a base on which the light emitting elements included in the first and second light emitting element groups are arranged on one main surface side.

  Further, the light irradiation device of the present invention includes the base in which the light emitting elements included in the first light emitting element group are arranged on one main surface side, the base, and the second light emitting element group in the above configuration. The light emitting element further includes a heat dissipating member having a length in the intersecting direction that is longer than that of the substrate.

  Furthermore, the light irradiation device of the present invention is configured so that, in the above-described configuration, the light emitted from the light emitting element in parallel to the object is opposed to the light emitting element included in the second light emitting element group. It further has a reflector that reflects to the object side.

  In the light irradiation device of the present invention having the above-described configuration, each of the light emitting elements included in the second light emitting element group emits light emitted from the light emitting element in parallel to the object. It has the reflective layer which reflects in the side.

  Furthermore, the printing apparatus of the present invention includes a printing unit that performs printing on a recording medium, and any one of the light irradiation devices of the present invention that irradiates light onto the printed recording medium. And

  According to the light irradiation device of the present invention, it is a light irradiation device for irradiating light to an object that moves relatively, and corresponds to the width of the object in a crossing direction that intersects the moving direction of the object. A first light emitting element group disposed in a crossing direction, and a second light emitting element group disposed across the first light emitting element group along the intersecting direction, and the first and second light emitting element groups. Each light-emitting element included in the light-emitting element group includes a plurality of semiconductor layers including a light-emitting layer, and each of the light-emitting elements included in the first light-emitting element group has a stacking direction of the semiconductor layers. Each of the light emitting elements included in the second light emitting element group is disposed so as to intersect a plane including the moving direction and the intersecting direction, and the stacking direction of the semiconductor layers is the same as the moving direction and the intersecting direction. Parallel to the containing plane Since it was urchin disposed, it is possible to shorten the length in the cross direction of the light irradiation device of the present invention, it is possible to miniaturize, obtain light emitting device to achieve a cost reduction.

It is a top view which shows an example of the form of the light irradiation device of this invention. It is sectional drawing along the 1I-1I line | wire of the light irradiation device shown in FIG. FIG. 2 is a cross-sectional view of the light irradiation device shown in FIG. 1 taken along the line II-II. It is a top view for demonstrating arrangement | positioning of a 2nd light emitting element. It is a top view for demonstrating arrangement | positioning of a 2nd light emitting element. It is sectional drawing corresponding to FIG. 2 for demonstrating a sealing material and an optical lens. It is sectional drawing corresponding to FIG. 3 for demonstrating a sealing material and an optical lens. It is a top view of the printing apparatus using the light irradiation device shown in FIG. It is a side view of the printing apparatus shown in FIG. It is a top view which shows the 1st modification of the light irradiation device shown in FIG.

  Hereinafter, examples of embodiments of the light irradiation device and the printing apparatus of the present invention will be described with reference to the drawings. The following examples illustrate the embodiments of the present invention, and the present invention is not limited to the examples of these embodiments.

  The light irradiation device 1 shown in FIGS. 1, 2, and 3 is incorporated in a printing apparatus such as an offset printing apparatus or an inkjet printing apparatus that uses ultraviolet curable ink, and moves relative to the object (recording medium). By irradiating ultraviolet rays after depositing the ultraviolet curable ink on the surface, it functions as an ultraviolet ray generating light source for curing the ultraviolet curable ink.

(Light irradiation device)
The light irradiation device 1 is disposed in the base 10 having a plurality of openings 12 on one main surface 11 a, the plurality of connection pads 13 provided in each opening 12, and the openings 12 in the base 10, And a plurality of light emitting elements 20 electrically connected to the connection pads 13.

  The base 10 includes a laminated body 40 in which a first insulating layer 41 and a second insulating layer 42 are laminated, and an electrical wiring 50 that connects the light emitting elements 20 to each other. The light emitting element 20 is supported in an opening 12 provided on the one main surface 11a.

  The first insulating layer 41 is made of, for example, a ceramic such as an aluminum oxide sintered body, an aluminum nitride sintered body, a mullite sintered body, and a glass ceramic, and a resin such as an epoxy resin and a liquid crystal polymer (LCP). It is formed.

  The electric wiring 50 is formed in a predetermined pattern by a conductive material such as tungsten (W), molybdenum (Mo), manganese (Mn), and copper (Cu), and the electric current to the light emitting element 20 or the light emitting element It functions as a power supply wiring for supplying current from 20.

  In the second insulating layer 42 stacked on the first insulating layer 41, an opening 12 that penetrates the second insulating layer 42 is formed.

  The shape of each opening 12 is such that the inner peripheral surface 14 is inclined so that the hole diameter is larger on the one main surface 11a side of the substrate 10 than the mounting surface of the light emitting element 20, It has a circular shape. The opening shape is not limited to a circular shape, and may be a rectangular shape.

  Such an opening 12 has a function of reflecting light emitted from the light emitting element 20 on its inner peripheral surface 14 upward to improve light extraction efficiency.

  In order to improve the light extraction efficiency, the material of the second insulating layer 42 is a porous ceramic material having a relatively good reflectivity with respect to light in the ultraviolet region, such as an aluminum oxide sintered body, zirconium oxide. It is preferable to form the sintered body and the aluminum nitride sintered body. Further, from the viewpoint of improving the light extraction efficiency, a metal reflection film may be provided on the inner peripheral surface 14 of the opening 12.

  The base 10 provided with the laminate 40 composed of the first insulating layer 41 and the second insulating layer 42 as described above is a case where the first insulating layer 41 and the second insulating layer 42 are made of ceramics or the like. If there is, it is manufactured through the following steps.

  First, a plurality of ceramic green sheets manufactured by a conventionally known method are prepared. A hole corresponding to the opening is formed in the ceramic green sheet corresponding to the opening 12 by a method such as punching. Next, a metal paste to be the electric wiring 50 is printed (not shown) on the green sheet, and then the green sheet is laminated so that the printed metal paste is positioned between the green sheets. Examples of the metal paste used for the electric wiring 50 include a paste containing a metal such as tungsten (W), molybdenum (Mo), manganese (Mn), and copper (Cu). Next, the base body 10 having the electrical wiring 50 and the opening 12 can be formed by firing the laminate and firing the green sheet and the metal paste together.

  Further, if the first insulating layer 41 and the second insulating layer 42 are made of a resin, for example, the following method can be considered as a method for manufacturing the substrate 10.

  First, a precursor sheet of a thermosetting resin is prepared. Next, a plurality of precursor sheets are laminated so that lead terminals made of a metal material to be the electrical wiring 50 are arranged between the precursor sheets and the lead terminals are embedded in the precursor sheets. Examples of the material for forming the lead terminal include copper (Cu), silver (Ag), aluminum (Al), iron (Fe) -nickel (Ni) -cobalt (Co) alloy, and iron (Fe) -nickel (Ni). Examples include metal materials such as alloys. And after forming the hole corresponding to the opening part 12 in a precursor sheet | seat by methods, such as a laser processing and an etching, the base | substrate 10 is completed by thermosetting this. In addition, when forming the opening part 12 by laser processing, you may process after thermosetting a precursor sheet | seat.

  On the other hand, in the opening 12 of the substrate 10, a connection pad 13 electrically connected to the light emitting element 20 and a bonding material 15 such as solder, gold (Au) wire, aluminum (Al) wire, etc. are connected to the connection pad 13. Are connected to each other.

  The connection pad 13 is formed of a metal layer made of a metal material such as tungsten (W), molybdenum (Mo), manganese (Mn), and copper (Cu). If necessary, a nickel (Ni) layer, a palladium (Pd) layer, a gold (Au) layer, or the like may be further stacked on the metal layer. The connection pad 13 is connected to the light emitting element 20 by a bonding material 15 such as solder, gold (Au) wire, or aluminum (Al) wire.

  Although not shown, the light-emitting element 20 includes a plurality of semiconductor layers 22 including a light-emitting layer stacked, and a light-emitting element 20a belonging to the first light-emitting element group 20A and a light-emitting element belonging to the second light-emitting element group 20B. Similarly, the opening 12 is divided into an opening 12a in which the light emitting element 20a is disposed, and an opening 12b in which the light emitting element 20b is disposed.

  20 A of 1st light emitting element groups are arrange | positioned corresponding to the width | variety of the target object in the cross direction X2 which cross | intersects the moving direction X1 of a target object. Here, the arrangement corresponding to the width of the object does not necessarily mean that the width is the same as the width of the object, but the light emitting elements 20a included in the first light emitting element group 20A. Of these, it is only necessary that the respective positions of the light emitting elements 20a located at both ends in the cross direction X2 are substantially equal to the positions of both ends in the cross direction X2 of the object. For example, the positions of the light emitting elements 20a located at both ends may be inside the positions of both ends in the intersecting direction X2 of the target object, or both may be outside. What is necessary is just to adjust suitably so that the illumination intensity of the ultraviolet-ray irradiated to a target object may become more than predetermined with the 2nd light emitting element group 20B and 20 A of 1st light emitting element groups which are demonstrated later.

In the first light emitting element group 20A of this example, eight light emitting elements 20a are arranged in the cross direction X2, and eight light emitting elements 20a are arranged in a vertical and horizontal arrangement, that is, in a lattice shape in the moving direction X1. As a matter of course, the openings 12a in which the light emitting elements 20a are arranged are also arranged in a lattice pattern, similarly to the light emitting elements 20a. The first light emitting elements 20a of the present example are arranged in a grid pattern, but may be arranged in a regular grid pattern or a zigzag pattern, that is, arranged in a plurality of zigzags. There is no need to limit the shape. Here, the arrangement in a staggered pattern is synonymous with the arrangement so as to be positioned at the lattice points of the oblique lattice, and by arranging in this manner, the light emitting elements 20a can be arranged at a higher density. Thus, the illuminance per unit area can be increased.

  The light emitting element 20a is arranged so that the stacking direction (not shown) of the semiconductor layer 22 intersects a plane including the moving direction X1 and the intersecting direction X2. That is, in the case of the light emitting element 20a, the stacked planes of the semiconductor layers 22 including the light emitting layer are arranged so as to be substantially parallel to the plane including the moving direction X1 and the crossing direction X2. In general, the illuminance of light emitted from the light emitting element 20 is strongest in the stacking direction of the semiconductor layers 22, and therefore the light emitted toward the object of the first light emitting element group 20A can be high.

  On the other hand, the second light emitting element group 20B is arranged along the intersecting direction X2 with the first light emitting element group 20A interposed therebetween. That is, the second light emitting element group 20B is disposed on both ends in the crossing direction X2 of the object. Here, the arrangement corresponding to the positions of both ends in the intersecting direction X2 of the object does not necessarily mean that the positions of both ends in the intersecting direction X2 of the object coincide with each other. The light emitting elements 20b included in the light emitting element group 20B may be substantially equal to the positions of both ends in the intersecting direction X2. For example, any of the light emitting element groups 20B located on both sides of the light emitting element group 20A may be disposed inside the positions of both ends in the cross direction X2 of the target object, or disposed across the positions of both ends. It may be arranged outside the positions of both ends. As described above, the first light-emitting element group 20A and the second light-emitting element group 20B may be appropriately adjusted so that the illuminance of ultraviolet rays applied to the object is equal to or higher than a predetermined value.

  In the second light emitting element group 20B of the present example, two light emitting elements 20b in the crossing direction X2 and 8 in the moving direction X1 are respectively provided on one end side and the other end side in the crossing direction X2 of the first light emitting element group 20A. The light emitting elements are arranged in a grid pattern. That is, in the light emitting element group 20B as a whole, four light emitting elements 20b are arranged in a grid pattern in the crossing direction X2, and eight light emitting elements are arranged in the moving direction X1. In this example, two light emitting elements 20b included in the second light emitting element group 20B are disposed inside the opening 12b.

  The light emitting element 20b is arranged so that the stacking direction (not shown) of the semiconductor layer 22 is parallel to a plane including the moving direction X1 and the intersecting direction X2. That is, in the case of the light emitting element 20b, the stacked planes of the semiconductor layers 22 including the light emitting layer are arranged so as to be substantially perpendicular to the plane including the moving direction X1 and the crossing direction X2. In the case of this example, the stacking direction of the semiconductor layers 22 is arranged so as to be parallel to the crossing direction X2, but may be arranged so as to be parallel to the movement direction X1 as shown in FIG. As shown in FIG. 5, the moving direction X1 and the crossing direction X2 may be arranged so as to have an inclination.

  Here, the arrangement interval in the crossing direction X2 between the light emitting elements 20a and 20b adjacent to each other in the light emitting element 20a included in the first light emitting element group 20A and the light emitting element 20b included in the second light emitting element group 20B is: It is shorter than the arrangement interval in the intersecting direction X2 between the light emitting elements 20a included in the first light emitting element group 20A. Here, the arrangement interval is the actual interval between adjacent light emitting elements 20a and 20b when the first light emitting elements 20a and the second light emitting elements 20b are not arranged in a line along the intersecting direction X2. It is not a so-called linear distance, but an interval when viewed in the direction along the crossing direction X2 (a distance along a straight line in the crossing direction X2).

  As with the light emitting element 20a, the light emitting element 20b generally has the highest illuminance of light emitted from the light emitting element 20 in the stacking direction of the semiconductor layer 22, but also in the direction perpendicular to the stacking direction of the semiconductor layer 22. Is irradiated. Further, since the light emitting elements 20b are arranged so that the stacking direction of the semiconductor layers 22 is parallel to a plane including the moving direction X1 and the crossing direction X2, the arrangement interval between the light emitting elements 20b and the light emitting elements 20b And the arrangement interval between the adjacent light emitting elements 20a can be shortened. Therefore, a plurality of light emitting elements 20b can be arranged in an area where one light emitting element 20a is arranged. Specifically, in this example, one light emitting element 20a is disposed in the opening 12a, but two light emitting elements 20b are disposed in the opening 12b. With this arrangement, the illuminance of light emitted from the opening 12b can be made higher than the illuminance of light emitted from the opening 12a.

  Therefore, since the illuminance of ultraviolet rays can be kept high in the vicinity of both ends of the cross direction X2 of the object, the length of the light irradiation device 1 in the cross direction X2 can be shortened, thereby reducing the size and cost. Can be realized.

  In addition, the light emitting element 20b of this example is arrange | positioned so that the lamination direction (not shown) of the semiconductor layer 22 may oppose the internal peripheral surface 14. FIG. By arranging in this way, the illuminance of light emitted from the light emitting element 20 is generally the strongest in the stacking direction of the semiconductor layer 22, so that strong light emitted from the second light emitting element 20 b is generated on the inner peripheral surface 14. Since the light can be efficiently reflected upward, the illuminance of light emitted from the opening 12b can be further increased.

The light emitting elements 20a and 20b are formed by stacking a p-type semiconductor layer and an n-type semiconductor layer made of a semiconductor material such as gallium arsenide (GaAs) or gallium nitride (GaN) on an element substrate 21 such as a sapphire substrate. A light emitting diode, or an organic EL element having a semiconductor layer made of an organic material.

  The light emitting element 20a is connected to a semiconductor layer 22 having a light emitting layer and a connection pad 13 disposed on the base 10 via a first bonding material 15a such as a gold (Au) wire or an aluminum (Al) wire. And device electrodes 23 and 24 made of a metal material such as silver (Ag), and are wire-bonded to the base 10. The light emitting element 20 a emits light having a predetermined wavelength with a predetermined luminance according to the current flowing between the element electrodes 23 and 24, and emits the light to the outside through the element substrate 21. As is well known, the element substrate 21 can be omitted.

  On the other hand, the light emitting element 20b is a silver layer connected to the semiconductor layer 22 having a light emitting layer and a connection pad 13 disposed on the substrate 10 via a second bonding material 15b such as solder or gold (Au) bump. Device electrodes 23 and 24 made of a metal material such as (Ag) are provided, and are flip-chip bonded to the substrate 10. The light emitting element 20b emits light having a predetermined wavelength with a predetermined luminance according to the current flowing between the element electrodes 23 and 24, and emits the light to the outside via the element substrate 21. The element substrate 21 can be omitted as in the light emitting element 20a.

In the present example, an LED that emits UV light (ultraviolet light) having a wavelength spectrum peak of 250 to 395 [nm] or less is employed. That is, in this example, a UV-LED element is adopted as the light emitting element 20. The light emitting elements 20a and 20b of this example are UV-LED elements having the same spectrum peak and illuminance of emitted light, and the light emitting elements 20a and 20b are formed by a conventionally well-known thin film forming technique. In this example, the light-emitting elements 20a and 20b are the same UV-LED element, but may be appropriately adjusted so that the illuminance of the ultraviolet rays applied to the object becomes a predetermined level or more.

  The light irradiation device 1 has a flat plate-like heat radiating member 100 for radiating heat generated by driving of the light emitting elements 20a and 20b. The heat radiating member 100 functions as a support for the base 10 and as a heat radiating body for radiating heat generated by the base 10 to the outside. The substrate 10 disposed on the heat radiating member 100 is disposed on one main surface 101a of the heat radiating member 100 via an adhesive 120 such as silicone resin or epoxy resin. The heat radiating member 100 is preferably made of a material having high thermal conductivity, and examples thereof include various metal materials, ceramics, and resin materials. The heat radiating member 100 of this example is made of copper. Note that the heat dissipating member 100 is not always necessary, and may be omitted if heat generated by the first light emitting element 20a and the second light emitting element 20b is not a problem.

  The first light emitting element 20a and the second light emitting element 20b may be sealed with a sealing material 30 as shown in FIGS. An insulating material such as a light-transmitting resin material may be used for the sealing material 30, and moisture can enter from outside by sealing the first light emitting element 20a and the second light emitting element 20b satisfactorily. The first light emitting element 20a and the second light emitting element 20b are protected by preventing or absorbing an external impact.

  Further, the sealing material 30 includes a refractive index (1.7 for sapphire) of the element substrate 21 constituting the first light emitting element 20a and the second light emitting element 20b and a refractive index of air (about 1.0). By using a material having a refractive index between, for example, silicone resin (refractive index: about 1.4), the light extraction efficiency of the first light emitting element 20a and the second light emitting element 20b can be improved. it can. The sealing material 30 is formed by mounting the first light emitting element 20a and the second light emitting element 20b on the base 10, filling the opening 12 with a precursor such as silicone resin, and curing the precursor. can do.

  Also, as shown in FIGS. 6 and 7, the optical lens 16 is arranged on the sealing material 30 so as to cover the first light emitting element 20a and the second light emitting element 20b with the lens adhesive 17 interposed therebetween. Also good. In the light irradiation device 1 shown in FIGS. 6 and 7, a plano-convex lens is used as the optical lens 16. In other words, the optical lens 16 of the present example has a convex surface on one main surface and a flat surface on the other main surface, and the cross-sectional area decreases from the other main surface toward the main surface.

  The optical lens 16 is formed of, for example, a silicone resin and has a function of collecting light emitted from the first light emitting element 20a and the second light emitting element 20b. As the material of the optical lens, in addition to the above-described silicone resin, thermosetting resin such as urethane resin and epoxy resin, or plastic such as thermoplastic resin such as polycarbonate resin and acrylic resin, sapphire, or inorganic glass can be cited. It is done.

(Embodiment of printing apparatus)
As an example of the embodiment of the printing apparatus of the present invention, the printing apparatus 200 shown in FIGS. 8 and 9 will be described as an example. The printing apparatus 200 includes a conveying unit 210 for conveying the recording medium 250, a printing unit 220 as a printing mechanism for printing on the conveyed recording medium 250, and an ultraviolet ray for the recording medium 250 after printing. The light irradiation device 1 that irradiates light and the control mechanism 230 that controls the light emission of the light irradiation device 1 are provided. The recording medium 250 corresponds to the above-described object.

The transport unit 210 is for transporting the recording medium 250 so as to pass through the printing unit 220 and the light irradiation device 1 in this order. The transport unit 210 and the mounting table 211 are arranged so as to face each other and are rotatably supported. And a roller 212. The transport unit 210 is for sending the recording medium 250 supported by the mounting table 211 between the pair of transport rollers 212 and rotating the transport roller 212 to feed the recording medium 250 in the transport direction. .

  The printing unit 220 has a function of attaching a photosensitive material to the recording medium 250 conveyed via the conveying unit 210. The printing unit 220 is configured to eject droplets containing the photosensitive material toward the recording medium 250 and attach the droplets to the recording medium 250. In this example, ultraviolet curable ink is used as the photosensitive material. Examples of the photosensitive material include, in addition to the ultraviolet curable ink, a photosensitive resist or a photocurable resin.

  In this example, a line-type printing unit is employed as the printing unit 220. The printing unit 220 includes a plurality of ejection holes 220a arranged in a line, and is configured to eject ultraviolet curable ink from the ejection holes 220a. The printing unit 220 ejects ink from the ejection holes 220a to the recording medium 250 conveyed in a direction orthogonal to the arrangement of the ejection holes 220a, and deposits the ink on the recording medium, thereby applying the recording medium to the recording medium. Printing is performed.

  In this example, the line-type printing unit is exemplified as the printing mechanism. However, the printing mechanism is not limited to this. For example, a serial-type printing unit may be employed, or a line-type or serial-type printing unit may be used. You may employ | adopt a spray head (for example, inkjet head). Further, as the printing mechanism, an electrostatic head that accumulates static electricity on the recording medium 250 and attaches the photosensitive material with the static electricity may be employed. Alternatively, the recording medium 250 may be immersed in a liquid photosensitive material and the photosensitive medium may be used. An immersion apparatus for attaching a conductive material may be employed. Further, a brush, a brush, a roller, or the like may be employed as a printing mechanism.

  In the printing apparatus 200, the light irradiation device 1 has a function of exposing the photosensitive material attached to the recording medium 250 conveyed through the conveying unit 210. The light irradiation device 1 is provided on the downstream side in the transport direction with respect to the printing unit 220. In the printing apparatus 200, the light emitting element 20 has a function of exposing the photosensitive material attached to the recording medium 250.

  The control mechanism 230 has a function of controlling light emission of the light irradiation device 1. The memory of the control mechanism 230 stores information indicating the characteristics of light that makes it relatively good to cure the ink droplets ejected from the printing unit 220. Specific examples of the stored information include wavelength distribution characteristics suitable for curing ejected ink droplets, and numerical values representing emission intensity (emission intensity in each wavelength range). In the printing apparatus 200 of this example, by including the control mechanism 230, the magnitude of the drive current input to the plurality of light emitting elements 20 can be adjusted based on the stored information of the control mechanism 230. From this, according to the printing apparatus 200 of this example, light can be irradiated with an appropriate ultraviolet irradiation energy according to the characteristics of the ink to be used, and the ink droplet can be cured with a relatively low energy light. it can.

  In the printing apparatus 200, the transport unit 210 transports the recording medium 250 in the transport direction. The printing unit 220 ejects the ultraviolet curable ink 6 to the recording medium 250 being conveyed, and causes the ultraviolet curable ink to adhere to the surface of the recording medium 250. At this time, the ultraviolet curable ink 6 to be attached to the recording medium 250 may be attached to the entire surface, partially attached, or attached in a desired pattern. In the printing apparatus 200, the ultraviolet curable ink attached to the recording medium 250 is irradiated with ultraviolet rays emitted from the light irradiation device 1 to cure the ultraviolet curable ink.

According to the printing apparatus 200 of this example, the above-described effects of the light irradiation device 1 can be achieved.

  Although specific embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications can be made without departing from the scope of the present invention.

  For example, as in the first modification of the light irradiation device 1 shown in FIG. 10, the light emitting element 20 a is disposed in the opening 12 a of the base 10, and the light emitting element 20 b is disposed on the one main surface 101 a of the heat dissipation member 100. ing. As a matter of course, the length of the heat radiation member 100 in the cross direction X2 is longer than the length of the base body 10 in the cross direction X2. If the connection pad 13 is disposed on one main surface of the heat dissipation member 100 via an insulating film such as an epoxy resin, it is possible to prevent the second light emitting element 20b and the heat dissipation member 100 from being electrically short-circuited. By arranging in this way, the heat dissipation effect of the light emitting element 20b can be enhanced, and the area of the substrate 10 can be reduced, so that the cost can be reduced.

  Although not shown, a reflector is provided along both sides of the light emitting element 20b included in the light emitting element group 20B in the moving direction X1 in FIG. 10 to reflect the light irradiated in parallel to the object toward the object. May be. Such a reflecting plate may be a plate-like reflecting plate extending from one end to the other end of the row in the moving direction X1 of the light emitting elements 20b, or may be a curved reflecting plate. Moreover, it may be provided corresponding to each of the light emitting elements 20b, may be provided corresponding to a plurality of the light emitting elements 20b, and may reflect light parallel to the object to the object side. Any shape may be used. The material of the reflector may be a metal such as aluminum (Al) that reflects UV rays well, or a porous ceramic material such as an aluminum oxide sintered body, a zirconium oxide sintered body, and an aluminum nitride sintered body. It may be a ligation.

  When such a reflector is provided on the side of the light emitting element 20b in the stacking direction, it can reflect the light irradiated in parallel with the object most efficiently to the object side.

Further, although not shown, a reflective layer may be stacked so as to sandwich the light emitting layers of the first light emitting element 20a and the second light emitting element 20b. Here, sandwiching the light emitting layer does not mean that a reflective layer is laminated on both sides of the light emitting layer, but several semiconductor layers are generally laminated on both sides of the light emitting layer. Yes, reflective layers are stacked on both sides of these semiconductor layers. Such a reflective layer can improve the light extraction efficiency from the direction perpendicular to the stacking direction of the semiconductor layers 22 by reflecting light emitted from the light emitting layer parallel to the object to the light emitting layer side. Such a reflective layer is called a DBR (Distributed Bragg Reflector) layer and is generally formed by laminating a plurality of layers having two different refractive indexes. Specifically, it may be made of AlGaAs / GaAs, AlAs / GaAs, AlN / GaN, or the like.

  Further, in the first modification of the light irradiation device 1 shown in FIG. 10, the second light emitting element 20b is disposed on the upper surface of the one main surface 101a of the heat dissipation member 100. Similarly to the opening 12 formed in the base 10 on the main surface 101a, an opening may be provided, and the second light emitting element 20b may be disposed in the opening. The opening has an inner peripheral surface inclined so that the hole diameter is larger on the one main surface 101a side of the heat dissipation member 100 than the mounting surface of the light emitting element 20, and when viewed in plan, for example, a circular shape It has become. The opening shape is not limited to a circular shape, and may be a rectangular shape. Such an opening may be formed by cutting or laser processing.

  The embodiment of the printing apparatus 200 is not limited to the above embodiment. For example, a so-called offset printing type printer that rotates a shaft-supported roller and conveys a recording medium along the roller surface may exhibit the same effect.

  In the above-described embodiment, an example in which the light irradiation device 1 is applied to the printing apparatus 200 using the inkjet head 220 is shown. The light irradiation device 1 cures, for example, a photo-curing resin spin-coated on the surface of the object. It can also be applied to light irradiation for curing various photo-curing resins, such as a dedicated device. Moreover, you may use the light irradiation device 1 for the irradiation light source etc. in an exposure apparatus, for example.

DESCRIPTION OF SYMBOLS 1 Light irradiation device 10 Base | substrate 11a One main surface 12 Opening part 13 Connection pad 14 Inner peripheral surface 15 Bonding material 15a 1st bonding material 15b 2nd bonding material 16 Optical lens 17 Lens adhesive 20 Light emitting element 20a 1st light emission Element 20b Second light emitting element 21 Element substrate 22 Semiconductor layers 23 and 24 Element electrode 30 Sealing material 40 Laminate 41 First insulating layer 42 Second insulating layer 50 Electric wiring 100 Heat radiation member 101a One main surface 120 Adhesive Agent 200 Printing device 210 Conveying means 211 Loading table 212 Conveying roller 220 Printing means 220a Discharge hole 230 Control mechanism 250 Recording medium

Claims (7)

A light irradiation module for irradiating a relatively moving object with light,
A first light emitting element group disposed corresponding to the width of the object in a crossing direction intersecting the moving direction of the target object, and the first light emitting element group sandwiched along the crossing direction. And a second light emitting element group.
Each light-emitting element included in the first and second light-emitting element groups includes a plurality of semiconductor layers including a light-emitting layer,
Each of the light emitting elements included in the first light emitting element group is disposed so that a stacking direction of the semiconductor layers intersects a plane including the moving direction and the intersecting direction,
Each of the light emitting elements included in the second light emitting element group is arranged so that the stacking direction of the semiconductor layers is parallel to a plane including the moving direction and the intersecting direction. Irradiation module. The light emitting elements included in the first and second light emitting element groups are arranged vertically and horizontally in each light emitting element group,
The arrangement interval in the crossing direction of the light emitting elements adjacent to each other in the light emitting elements included in the first light emitting element group and the light emitting elements included in the second light emitting element group is the first light emission. The light irradiation module according to claim 1, wherein the light irradiation module is shorter than an arrangement interval in the intersecting direction of the light emitting elements included in the element group.   The light irradiation module according to claim 1, further comprising a base on which the light emitting elements included in the first and second light emitting element groups are arranged on one main surface side. .   The light irradiation module includes a base on which the light emitting elements included in the first light emitting element group are arranged on one main surface side, and the light emitting elements included in the base and the second light emitting element group on one main surface. The light irradiation module according to claim 1, further comprising a heat dissipating member arranged on a side and having a length in the intersecting direction longer than that of the base body.   Opposite to the light emitting elements included in the second light emitting element group, the light emitting element further includes a reflecting plate that reflects the light irradiated in parallel to the object toward the object. The light irradiation module according to any one of claims 1 to 4.   Each of the light emitting elements included in the second light emitting element group includes a reflective layer that reflects light emitted from the light emitting elements in parallel to the object toward the light emitting layer. The light irradiation module according to any one of claims 1 to 4. Printing means for printing on a recording medium;
A printing apparatus comprising: the light irradiation module according to claim 1, which irradiates light onto the printed recording medium.

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