KR101930041B1

KR101930041B1 - Photoirradiation device

Info

Publication number: KR101930041B1
Application number: KR1020157030543A
Authority: KR
Inventors: 츠토무 키시네
Original assignee: 호야 칸데오 옵트로닉스 가부시키가이샤
Priority date: 2013-04-15
Filing date: 2014-03-31
Publication date: 2018-12-17
Also published as: WO2014171317A1; TW201502424A; CN105229368A; TWI620889B; KR20150132880A; CN105229368B; JP6360475B2; JPWO2014171317A1

Abstract

A light irradiation apparatus for irradiating a line-shaped light having a predetermined line width extending in a first direction and in a second direction orthogonal to the first direction, at a predetermined irradiation position on an irradiation surface, N (N is an integer of 2 or more) light source modules arranged at a first interval along a direction of the light source module and arranged so as to coincide with the direction of an optical axis in a predetermined direction, And an optical unit which has N optical elements for leading light from the light source to a predetermined optical path and emits line-shaped light parallel to the first direction with respect to the irradiation surface, wherein each light source module extends along the first direction And each optical element expands the light emitted from the light emitting portion at a predetermined magnification in the first direction, and when the first interval is a, the length of the light emitting portion in the first direction is b, and the predetermined magnification is? , The following conditional expression (1) is satisfied .
? x b? a ... (One)

Description

[0001] PHOTOIRRADIATION DEVICE [0002]

The present invention relates to a light irradiation apparatus for irradiating line-shaped irradiation light (irradiation light), and more particularly to a light irradiation apparatus including a plurality of light source modules arranged in a line on a substrate.

Conventionally, an ultraviolet curable ink which is cured by irradiation of ultraviolet light is used as ink for offset sheetfed printing. In addition, ultraviolet curable resins are used as sealants for FPD (Flat Panel Display), such as liquid crystal panels and organic EL (Electro Luminescence) panels. In order to cure the ultraviolet curing type ink or the ultraviolet curing resin, an ultraviolet ray irradiation apparatus which generally irradiates ultraviolet light is used. Especially in the application of the offset sheet laminator or FPD, A line light irradiating device for irradiating an irradiating light of a predetermined shape is used. Such a line light irradiating apparatus is described in, for example, Patent Document 1. [

The line light irradiating device disclosed in Patent Document 1 has a long substrate, a plurality of LEDs (Light Emitting Diode) arranged at regular intervals along the longitudinal direction of the substrate, and a plurality of LEDs Called LED unit having a rod lens for condensing light, and emits line light along the longitudinal direction of the substrate.

In addition, in order to stably and surely cure the ultraviolet curable ink or the ultraviolet curable resin, ultraviolet light with high irradiation intensity is required. Therefore, by using a plurality of LED units as described in Patent Document 1, (See, for example, Patent Document 2).

In the light irradiation apparatus described in Patent Document 2, a plurality of LED units are arranged radially (circularly) with respect to an object to be irradiated, and line light emitted from each LED unit is superimposed at a predetermined position on the object to be irradiated, Ultraviolet light having a high irradiation intensity is irradiated to the object to be irradiated

Japanese Patent Laid-Open Publication No. 2012-186015 Japanese Patent Application Laid-Open No. 2010-287547

According to the light irradiation apparatus described in Patent Document 2, ultraviolet light having an irradiation intensity proportional to the number of LED units can be irradiated. Therefore, if it is desired to obtain ultraviolet light with a high irradiation intensity, simply increase the number of LED units. However, there is a problem that the number of LED units that can be arranged radially due to the physical size of the LED unit is limited. In order to solve such a problem, it is considered to dispose each LED unit away from the object to be irradiated. With such an arrangement, there arises a problem that the whole light irradiation apparatus becomes large in size.

When a plurality of LED units are arranged radially as in the light irradiation device described in Patent Document 2, incidence angles of line light emitted from the LED units with respect to an object to be irradiated become different from each other. The line width (thickness) of the line light on the object to be irradiated becomes thick and the distribution of the irradiation intensity in the line width direction becomes gentle, so that the desired irradiation intensity is obtained There is also the problem that it does not. Such a problem is remarkable as the number of LED units arranged in a radial direction increases. Therefore, there is a demand to suppress the number of LED units to be used even from this point of view.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and an object of the present invention is to provide a light emitting device capable of emitting light in a line shape with high irradiation intensity without increasing the number of LED units (optical units) And to provide an irradiation device.

In order to attain the above object, a light irradiation apparatus of the present invention is a light irradiation apparatus comprising a plurality of light emitting elements arranged in a predetermined irradiation position on an irradiation surface and having a line shape having a predetermined line width extending in a first direction and in a second direction orthogonal to the first direction (N is an integer of 2 or more) light source modules arranged at a first interval along a first direction on a substrate and arranged so as to coincide with the direction of an optical axis in a predetermined direction, And an optical unit which is disposed on an optical path of each light source module and has N optical elements for leading light from each light source module to a predetermined optical path and emits light of a line shape parallel to the first direction with respect to the irradiation surface (M is an integer of 2 or more) light emitting elements arranged at a second interval shorter than the first interval along the first direction, and the light emitting units extending along the first direction Each optical element has (1) when the light emitted from the light portion is enlarged at a predetermined magnification in the first direction and the first interval is a, the length of the light emitting portion in the first direction is b, and the predetermined magnification is? , (2) and (3).

? x b? a ... (One)
0.30? B / a? (2)
3.3? (3)

According to such a configuration, light emitted from each light source module expands in the first direction, so that light emitted from the plurality of light source modules overlap each other at the irradiation position on the irradiation surface. For this reason, line-shaped light having a high peak intensity is emitted from the optical unit.

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Further, it is preferable that the light emitting element is an LED (Light Emitting Diode) having a substantially square light emitting surface.

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Each optical element is configured to condense light emitted from the light emitting element in the direction of the optical axis and in the third direction orthogonal to each of the first direction so that the light emitted from the light emitting element becomes a predetermined line width at the irradiation position can do.

Each of the optical elements has a first lens through which light from each light source module is incident and a second lens through which light transmitted through the first lens is incident, and the first lens is formed into a flat, convex or concave surface Wherein the second lens has an incident surface on which a cylindrical surface having a positive power is formed and a Trouser surface having positive power in the first direction and the third direction, And is preferably an aspherical lens having an emergent surface formed thereon.

Each of the optical elements has a first lens through which light from each light source module is incident and a second lens through which light transmitted through the first lens is incident, and the first lens is formed into a flat, convex or concave surface It is preferable that the second lens has an incident surface and an exit surface formed as a convex surface and the second lens is an aspherical lens having an incident surface formed in a plane and an exit surface in which a Trouser bottom surface having a positive power in the first direction and the third direction is formed Do.

Each of the optical elements has a first lens through which light from each light source module is incident and a second lens through which light transmitted through the first lens is incident, and the first lens is formed into a flat, convex or concave surface The second lens is preferably a spherical double convex lens having an incident surface and an exit surface formed of a convex surface and the second lens has an incident surface formed into a convex surface and an exit surface formed into a convex surface.

Further, the second lens can be configured to have a rectangular outer shape when viewed in the direction of the optical axis. In this case, it is preferable that the second lens of each optical element is connected along the first direction.

The light irradiating device has a plurality of optical units, and the plurality of optical units include a first optical unit and a plurality of optical units arranged in a first direction relative to the first optical unit, And the first optical unit and the second optical unit are arranged so that the optical path of the light emitted from each of the optical units is symmetrical about the waterline at the irradiation position when viewed in the first direction, In the circumferential direction. According to this configuration, light from the first optical unit and the second optical unit, which have different irradiation intensity distributions, are superimposed at the irradiation position, so that the light is uniform in its entirety and has a higher irradiation intensity.

As described above, according to the present invention, since the light emitted from a plurality of light source modules arranged along the first direction is superimposed in the first direction on the irradiation surface, / RTI > Therefore, there is provided a light irradiation apparatus capable of emitting light of a line shape having a high irradiation intensity without increasing the number of optical units (i.e., without increasing the size of the apparatus).

1 is an external view of a light irradiation apparatus according to an embodiment of the present invention.
2 is an enlarged view for explaining the configuration and arrangement of the LED unit mounted in the light irradiation apparatus according to the embodiment of the present invention.
Fig. 3 is an enlarged view for explaining the configuration of the LED unit shown in Fig. 2 (a).
4 is a cross-sectional view taken along line AA 'of FIG.
5 is a cross-sectional view taken along line BB 'of FIG.
Fig. 6 is an enlarged view of a portion (dotted line frame) in Fig.
7 is a view for explaining a configuration of an LED element of an LED unit mounted in a light irradiation apparatus according to an embodiment of the present invention.
8 is a diagram showing the irradiation intensity distribution in the Y-axis direction of the ultraviolet light emitted from the light irradiation apparatus of the present embodiment.
9 is a view showing the irradiation intensity distribution in the X-axis direction of the ultraviolet light emitted from the light irradiation apparatus of the present embodiment.
10 is a diagram showing the relationship between the length of the light emitting surface of the LED die mounted on the light irradiation apparatus according to the embodiment of the present invention and the efficiency of the emitted ultraviolet light.
11 is a view showing the relationship between the length of the light emitting surface of the LED die mounted on the light irradiation device according to the embodiment of the present invention and the length of the effective irradiation area.
12 is a diagram showing the relationship between the length of the light emitting surface of the LED die mounted on the light irradiation apparatus according to the embodiment of the present invention and the peak intensity of the emitted ultraviolet light.
13 is a diagram showing the relationship between the length of the light emitting surface of the LED die mounted on the light irradiation apparatus according to the embodiment of the present invention and the uniformity of the irradiation intensity distribution of the emitted ultraviolet light.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof is not repeated.

1 is an external view of a light irradiation apparatus 1 according to an embodiment of the present invention. The light irradiation apparatus 1 of the present embodiment is an apparatus mounted on a light source apparatus for curing an ultraviolet curable ink used as an ink for offset sheet printing or an ultraviolet curable resin used as a sealant in an FPD (Flat Panel Display) Is arranged above the object to be irradiated and emits line-shaped ultraviolet light to the object to be irradiated as will be described later (Fig. 2 (b)). In the present specification, the length (line length) direction of the line-shaped ultraviolet light emitted from the light irradiation device 1 is referred to as the X-axis direction (first direction) and the width ), And a direction orthogonal to the X axis and the Y axis (i.e., the vertical direction) is defined as the Z axis direction. Fig. 1 (a) is a front view of the light irradiation device 1 when viewed in the Y-axis direction. Fig. 1 (b) is a bottom view of the light irradiation device 1 when viewed in the Z-axis direction (from the lower side to the upper side in Fig. 1 (a)). 1 (c) is a side view of the light irradiation device 1 when viewed in the X-axis direction (from the right side to the left side in Fig. 1 (a)).

As shown in Fig. 1, the light irradiation device 1 includes a case 10, a base block 20, and five LED units 100a to 100e. The case 10 is a case for accommodating the base block 20 and the LED units 100a to 100e. The LED units 100a to 100e are all units that emit line-shaped ultraviolet light parallel to the X axis. In the present specification, the LED units 100a to 100e are collectively referred to as " optical unit 100 " .

The base block 20 is a support member for fixing the optical unit 100, and is formed of a metal such as stainless steel. As shown in Figs. 1 (b) and 1 (c), the base block 20 is a substantially rectangular plate-shaped member extending in the X-axis direction, and a lower surface thereof is a partially cylindrical surface recessed along the Y-axis direction. The LED units 100a to 100e extending in the X axis direction are arranged along the Y axis direction (that is, along the partial cylindrical surface) on the lower surface (that is, the partial cylindrical surface) of the base block 20, Or by soldering or the like.

The lower surface of the case 10 (lower surface of the light irradiation device 1) has an opening 10a and ultraviolet light from each of the LED units 100a to 100e passes through the opening 10a, As shown in FIG.

Fig. 2 is an enlarged view for explaining the configuration and arrangement of the optical unit 100 mounted on the light irradiation apparatus 1 according to the present embodiment. 2 (a) is an enlarged view of FIG. 1 (b). For convenience of explanation, the optical block 100 shown in FIG. 1 (b) The partial cylindrical surface of the anticipated block 20 is expanded in a plane (i.e., stretched to the left and right). 2 (b) is an enlarged cross-sectional view of FIG. 1 (c), showing the arrangement of the LED units 100a to 100e when viewed in the X-axis direction.

In the light irradiation apparatus 1 of the present embodiment, a position 100 mm away from the lower end (Z axis direction) of the case 10 (i.e., a position of 100 mm of working distance , And the object to be irradiated is conveyed from the right side to the left side along the Y-axis direction on the irradiation surface R by a conveyance device (not shown) . Ultraviolet light emitted from the LED units 100a to 100e is sequentially moved (scanned) on the object to be irradiated by successively transporting the object to be irradiated from the right to the left on the irradiation surface R, Or the ultraviolet curable resin is sequentially cured (fixed). In Fig. 2 (b), "F1" indicates a light collecting position on the irradiation surface R on which the ultraviolet light emitted from the LED units 100a to 100e is condensed. 2 (b), for convenience of explanation, the waterline of the irradiation surface R passing through the condensing position F1 is set at the center line O of the optical path of the ultraviolet light emitted from the light irradiation device 1, As shown in Fig.

As shown in Fig. 2A, when the light irradiation apparatus 1 of the present embodiment is viewed from the Z axis direction, the LED units 100a to 100e are arranged in the order from right to left (i.e. along the Y axis) . The LED units 100a, 100c and 100e are spaced apart from each other by a distance of P / 2 (i.e., 1/2 of the arrangement interval P of the LED modules 110) in the X-axis direction with respect to the LED units 100b and 100d (Described later in detail).

As shown in Fig. 2 (b), the LED units 100a to 100e according to the present embodiment have a circular arc with a radius of 125 mm centered on the light-converging position F1 when viewed in the X- And are spaced apart. In the present embodiment, the LED unit 100c is arranged above the light-converging position F1 so that the optical axis of the LED unit 100c substantially coincides with the center line O, and the LED units 100a to 100e, When viewed in the X-axis direction, are arranged in line symmetry with the center line O as a symmetry axis. The ultraviolet light from each of the LED units 100a to 100e is emitted toward the light converging position F1 on the reference irradiation surface R and is focused on the reference irradiation surface R on the reference light converging position F1 And the range of the line width LW is checked. In the present embodiment, the line width LW of the ultraviolet light is set to about ± 20 mm with respect to the light converging position F1, and the line length LL (length in the X-axis direction) is set to about 100 mm have. In the present embodiment, ultraviolet light having a high irradiation intensity is irradiated to the object to be irradiated by superimposing the ultraviolet light from the five LED units 100a to 100e at the condensing position F1.

Fig. 3 is a diagram for explaining the configuration of the LED units 100a to 100e, and is an enlarged view of Fig. 2 (a). 4 is a cross-sectional view taken along line AA 'of FIG. 3, and FIG. 5 is a cross-sectional view taken along the line BB of FIG. 3 And Fig. 6 is an enlarged view of a portion (dotted line frame) of Fig. 4, 5, and 6, a part of the configuration is omitted for easy understanding of the drawings. 4, 5, and 6, the optical axis of the ultraviolet light emitted from the LED module 110 of the LED units 100a to 100e is indicated by a dot-dash line, the optical path OP of the ultraviolet light is represented by a solid line have.

The LED units 100a to 100e of the present embodiment are different from each other only in their positions and have the same internal structure. Therefore, the LED unit 100c will be described below as a representative.

As shown in Fig. 2 (a) and Fig. 3, the LED unit 100c includes a rectangular substrate 101 extending in the X-axis direction and ten LED modules 110. [ The ten LED modules 110 are arranged on the substrate 101 densely along the center line CL of the substrate 101 extending in the X axis direction and electrically connected to the substrate 101 . The substrate 101 of the LED unit 100c is connected to an LED driving circuit (not shown), and the driving current from the LED driving circuit is supplied to each LED module 110 through the substrate 101. [ When driving current is supplied to each LED module 110, ultraviolet light of a light amount corresponding to the driving current is emitted from each LED module 110, and line-shaped ultraviolet light parallel to the X- / RTI > As will be described later, each LED module 110 of the present embodiment includes an LED element 111 having four LED (Light Emitting Diode) dies 111a incorporated therein (Fig. 3) The driving current supplied to each LED module 110 (i.e., each LED die 111a) is adjusted such that ultraviolet light having substantially the same irradiation intensity distribution is emitted from the LED module 111a. The line-shaped ultraviolet light emitted from the LED unit 100c has a predetermined irradiation intensity distribution in the X-axis direction on the irradiation surface R (details will be described later). 3, the arrangement interval P of the LED modules 110 in this embodiment is the same as the size of the package 111p of the LED element 111 described later, And is set to about 14 mm in the present embodiment.

3 to 6, the LED unit 100a includes an LED element 111 (light source module), a lens 113, and a lens 115 (optical element).

Fig. 7 is a view for explaining the configuration of the LED element 111, Fig. 7 (a) is a plan view, and Fig. 7 (b) is a cross-sectional view taken along the line C-C 'in Fig. As shown in Fig. 7, the LED element 111 of the present embodiment has a return package 111p, and has four LED dies 111a (light emitting elements) incorporated therein. The opening of the package 111p is sealed with a cover glass 111c. The LED die 111a is a semiconductor element having a substantially square light emitting surface and receiving a drive current from the LED drive circuit and emitting ultraviolet light having a wavelength of 365 nm. In the present embodiment, each LED die 111a has a light emitting surface of 0.85 x 0.85 mm, and is arranged at an interval of 1.2 mm along the center line of the package 111p (that is, the center line parallel to one set of opposing sides) Respectively. Each LED element 111 is attached to the substrate 101 such that the LED die 111a is arranged along the X-axis direction.

As shown in Figs. 3 to 6, a lens 113 and a lens 115 held by a lens holder (not shown) are arranged on the optical axis of each LED element 111. Fig. The lens 113 is a planar spherical convex lens formed by, for example, injection molding of a silicone resin, for example, on the side of the LED element 111. The lens 113 condenses the incident ultraviolet light while diffusing from each LED die 111a And guided to the lens 115 at the rear end. The lens 115 is an aspheric lens formed by, for example, injection molding of a silicone resin, and has an incident surface on which a cylindrical surface having power in the Y-axis direction is formed and a Troy low surface having a power different in the Y- And the ultraviolet light incident from the lens 113 is condensed in the Y axis direction, and at the same magnification (for example, about 10 times) in the X axis direction. 4, the ultraviolet light emitted from each of the LED elements 111 (i.e., each LED die 111a), when viewed in the X-axis direction, passes through the lens 113 and the lens 115 And is condensed at the condensing position F1. 5, the ultraviolet light emitted from each of the LED elements 111 passes through the lens 113 and the lens 115 and spreads in the X-axis direction when seen in the Y-axis direction, 111) and the irradiation surface (R). In the present embodiment, the lens 113 is a lens having a maximum diameter in the direction orthogonal to the optical axis of? 13.5 mm. The lens 115 is a lens having a rectangular cross section in the direction orthogonal to the optical axis. In the present embodiment, the lenses 115 of the LED units 100a are connected in the X-axis direction, Consists of. With this configuration, ultraviolet light incident from each LED die 111a is efficiently attracted onto the irradiation surface R (i.e., vignetting by the lens 113 and the lens 115 does not occur).

As described above, in the present embodiment, the ultraviolet light emitted from each of the LED elements 111 is superposed on the irradiation surface R in the X-axis direction so that ultraviolet light of high irradiation intensity (peak intensity) Units 100a to 100e. That is, each LED unit 100a to 100e itself emits ultraviolet light having a peak intensity higher than that of a conventional LED unit (for example, described in Patent Document 2). The light irradiation apparatus 1 of the present embodiment uses five LED units 100a to 100e having such a configuration and superposes ultraviolet light from the LED units 100a to 100e at the light converging position F1, Ultraviolet light having a higher irradiation intensity is irradiated to the object to be irradiated.

8 is a diagram showing the irradiation intensity distribution of the ultraviolet light emitted from the light irradiation device 1 of the present embodiment in the Y axis direction and shows the center position in the longitudinal direction of the light irradiation device 1 And the length LL (the length in the X-axis direction)) of the irradiation intensity distribution in the Y-axis direction. 8A shows the distribution of the intensity of ultraviolet light emitted from each of the LED units 100a to 100e and FIG. 8B shows the distribution of the total intensity of the ultraviolet light emitted from the five LED units 100a to 100e Intensity distribution. 8A and 8B, ultraviolet light from the five LED units 100a to 100e is superimposed at the condensing position F1, so that the condensing position F1 (see FIG. 8 , "0 mm"), ultraviolet light having a peak intensity (peak intensity of about 8000 mW / cm ² ) of the peak intensity of the ultraviolet light emitted from each of the LED units 100a to 100e is obtained.

9 is a view showing the irradiation intensity distribution of the ultraviolet light emitted from the light irradiation device 1 according to the present embodiment in the X axis direction and shows the center position in the width direction of the light irradiation device 1 ) In the X-axis direction. 9A shows the irradiation intensity distribution of the ultraviolet light emitted from each of the LED units 100a, 100c and 100e and FIG. 9B shows the irradiation intensity distribution of the ultraviolet light emitted from each of the LED units 100b and 100d And FIG. 9C shows the total irradiation intensity distribution of ultraviolet light emitted from the five LED units 100a to 100e. 9A and 9B, the irradiation intensity distribution of the ultraviolet light emitted from each LED element 111 of each of the LED units 100a to 100e is shown by a solid line , And the irradiation intensity distribution of the ultraviolet light emitted from the entire LED unit (that is, the sum of the ultraviolet light emitted from each LED element 111) is shown by a dotted line.

As described above, the ultraviolet light emitted from each LED element 111 of the present embodiment spreads in the X-axis direction by the lens 113 and the lens 115, and is irradiated onto the irradiation surface R. [ Since the ultraviolet light emitted from each of the LED elements 111 must be the ultraviolet light emitted from the four LED dies 111a arranged at equal intervals along the X axis direction, The irradiation intensity distribution in the X axis direction of the ultraviolet light becomes a discrete irradiation intensity distribution having four peaks. Ultraviolet light having such a discrete irradiation intensity distribution is irradiated onto the irradiation surface R in the X-axis direction at a predetermined magnification by the lens 113 and the lens 115 (Fig. 9 (a) and Fig. 9 (b)). As a result, ultraviolet light from the plurality of LED elements 111 is superimposed in the X-axis direction on the irradiation surface R and the center position in the longitudinal direction of the light irradiation device 1 The irradiation intensity is increased in a predetermined range (within a range of about ± 35 mm in the present embodiment) around the center of the length LL (the length in the X-axis direction) (Fig. 9 (a) and 9 (b)). As described above, in the present embodiment, ultraviolet light having a high peak intensity is obtained by superposing ultraviolet light from a plurality of LED elements 111 arranged in the X-axis direction in the X-axis direction. In this specification, a portion where ultraviolet light is superimposed and the peak intensity is high is referred to as " effective irradiation region ", and in this embodiment, an object to be irradiated is disposed at this portion.

As shown in Figs. 9A and 9B, the irradiation intensity distribution of the ultraviolet light emitted from each of the LED units 100a to 100e has a peak intensity in the effective irradiation region, (I.e., non-uniform). This is because the densities of the LED dies 111a arranged in the X axis direction are not constant and there is a portion where the LED die 111a is not arranged between the LED elements 111. [ Therefore, in the present embodiment, the LED units 100a, 100c, and 100 are mounted on the LED units 100b and 100d so that the irradiation intensity distribution of the ultraviolet light emitted from the entire light irradiation apparatus 1 becomes substantially uniform. (I.e., 1/2 of the arrangement interval P of the LED modules 110) in the axial direction. When the LED units 100a to 100e are arranged in this manner, portions where the irradiation intensity of ultraviolet light emitted from each of the LED units 100a to 100e is lowered on the irradiation surface R are eliminated. Therefore, the irradiation intensity distribution of the ultraviolet light of the entire light irradiation apparatus 1 (that is, the total irradiation intensity distribution of the ultraviolet light emitted from the five LED units 100a to 100e) is substantially uniform in the X- And the peak intensity is five times (about 8000 mW / cm ² ) of the peak intensity of the ultraviolet light emitted from each of the LED units 100a to 100e.

As described above, in each of the LED units 100a to 100e of the present embodiment, a plurality (10 pieces) of LED elements 111 each having a plurality of (four) LED dies 111a in the X axis direction are arranged, Ultraviolet light having a high peak intensity is emitted by expanding the ultraviolet light emitted from the LED element 111 in the X-axis direction. That is, ultraviolet light having a high peak intensity is emitted from each of the LED units 100a to 100e itself. By arranging the LED units 100a to 100e so that the ultraviolet light from the five LED units 100a to 100e is condensed at the light converging position F1 on the irradiation surface R, So that ultraviolet light of one irradiation intensity distribution is emitted. Therefore, with the light irradiation apparatus 1 having such a constitution, the ultraviolet curable ink and the ultraviolet curable resin on the object to be irradiated can be stably cured (fixed).

The present invention is not limited to the above-described configuration, and various modifications are possible within the scope of the technical idea of the present invention.

For example, the light irradiation apparatus 1 of the present embodiment has been described as having five LED units 100a to 100e. However, as described above, in each of the LED units 100a to 100e, The number of LED units to be used can be adjusted according to a desired peak intensity, and the light irradiating device 1 may be provided with one or more LED units.

Although the LED units 100a to 100e of the present embodiment are described as having ten LED modules 110, the ultraviolet light emitted from each of the LED modules 110 may overlap even on the irradiation surface R The peak intensity of ultraviolet light can be increased. Therefore, each of the LED units 100a to 100e may have at least two LED modules 110 in the X-axis direction.

Although the LED element 111 of the present embodiment has been described as having four LED die 111a arranged at intervals of 1.2 mm in the X axis direction with the light emitting surface of 0.85 x 0.85 mm, The number of the LED die 111a, and the interval of the LED die 111a are not necessarily limited to such a configuration. That is, when the ultraviolet light emitted from the LED element 111 is expanded in the X-axis direction, the ultraviolet light from the other LED element 111 (for example, the adjacent LED element 111) The peak intensity of the ultraviolet light can be enhanced. Therefore, the LED element 111 may be any element that can emit ultraviolet light extending in the X-axis direction, and instead of having a plurality of LED dies 111a, (One LED die 111a) extending in the X-axis direction can be applied to the present invention. In this case, the size (length) of the light emitting surface is determined by the length of the light emitting portion composed of the plurality of LED dies 111a of the present embodiment (i.e., the length of the region in which the plurality of LED dies 111a are arranged in the X- The length of the effective irradiation region, the peak intensity of the desired ultraviolet light, the uniformity of the irradiation intensity distribution of the desired ultraviolet light, and the like, are appropriately set in consideration of the size of the lens 113 and the lens 115 to be used. However, in order to expand the ultraviolet light emitted from one LED element 111 in the X-axis direction and overlap with the ultraviolet light from the other LED elements 111, the distance between the LED elements 111 is a, The length in the axial direction is b, and the magnification in the X-axis direction by the lens 113 and the lens 115 is?, The following condition (1) is satisfied.

? x b? a ... (One)

10 to 13 are graphs showing the results of the simulation performed by the inventor to determine the length of the light emitting surface (light emitting portion) of the LED die 111a. 10 shows the result of simulating the relationship between the length (light emission length) of the light emitting surface of the LED die 111a and the efficiency of the emitted ultraviolet light. Here, the efficiency of the emitted ultraviolet light refers to the efficiency of the ultraviolet light emitted from the LED die 111a. In this specification, (the light amount of the ultraviolet light on the irradiation surface R) / The amount of ultraviolet light emitted). 11 shows the result of simulating the relationship between the length of the light emitting surface of the LED die 111a and the length of the effective irradiation area. 12 is a simulation result of the relationship between the length of the light emitting surface of the LED die 111a and the peak intensity of the emitted ultraviolet light. 13 shows the result of simulating the relationship between the length of the light emitting surface of the LED die 111a and the uniformity of the irradiation intensity distribution of the emitted ultraviolet light. The uniformity of the irradiation intensity distribution of the emitted ultraviolet ray means the unevenness of the irradiation intensity within the effective irradiation region. In this specification, the term "(maximum intensity in the effective irradiation region) - (minimum intensity in the effective irradiation region) (Maximum intensity in the effective irradiation area) + (minimum intensity in the effective irradiation area)). In the simulations shown in Figs. 10 to 13, the same lens 113 and lens 115 as in the present embodiment are disposed on the optical path of the LED element 111, and each LED module 110 (Element 111) were arranged at intervals of 14 mm, which is the same as that of the present embodiment.

As shown in Fig. 10, when the length (light emission length) of the light emitting surface of the LED die 111a becomes long, the efficiency of the emitted ultraviolet light gradually decreases. This is because the length of the light emitting surface of the LED die 111a becomes long and vignetting is caused by the lens 113 and the lens 115 (that is, a part of the ultraviolet light emitted from the light emitting surface passes through the lens 113 and the lens 115) (I.e., it is not accepted by the user 115). Therefore, when the lens 113 and the lens 115 of the present embodiment are used, it is preferable that the length of the light emitting surface of the LED die 111a is 5.8 mm or less.

As shown in Fig. 11, when the length (light emission length) of the light emitting surface of the LED die 111a becomes long, the effective irradiation region length (effective irradiation region length) is gradually shortened. This is because, when the emission length becomes longer, the peak intensity becomes higher because the superposition of the ultraviolet light is increased at the center of the effective irradiation area length, but the irradiation intensity on both ends of the effective irradiation area length is relatively lowered. Therefore, when the effective irradiation area length? 70 mm is set as the target value, the length of the light emitting surface of the LED die 111a is preferably 5.8 mm or less.

As shown in Fig. 12, when the length (light emission length) of the light emitting surface of the LED die 111a becomes long, the peak intensity of the emitted ultraviolet light gradually increases. This is because the length of the ultraviolet light irradiated from each LED die 111a on the irradiation surface R becomes longer, so that the length of the ultraviolet light superimposed in the X-axis direction becomes longer. Therefore, if the peak intensity of the ultraviolet light is 600 mW as the target value, the length of the light emitting surface of the LED die 111a is preferably 4.2 mm or more.

As shown in Fig. 13, the uniformity of the ultraviolet light emitted according to the length (light emission length) of the light emitting surface of the LED die 111a is changed. Therefore, if the uniformity of the irradiation intensity distribution of the ultraviolet light is? 7% as the target value, the length of the light emitting surface of the LED die 111a is preferably 4.2 mm or more.

From the above simulation results, considering the efficiency of the ultraviolet light, the length of the effective irradiation area, the peak intensity of the ultraviolet light, and the uniformity of the irradiation intensity distribution of the ultraviolet light, the length b of the light emitting surface of the LED die 111a is 4.2 mm To 5.8 mm. Considering that the interval a of the LED element 111 of the present embodiment is 14 mm, the following conditional expression (2) is obtained from the conditional expression (1).

0.30? B / a? (2)

That is, it is preferable that the length (b) of the light emitting surface of the LED die 111a is set in the range of 0.30 to 0.42 with respect to the interval (a) of the LED elements 111.

From the conditional expressions (1) and (2), the following conditional expressions (3) and (4) are obtained.

3.3? (3)

2.3? (4)

That is, when the distance a between the LED elements 111 and the length b of the light emitting surface of the LED die 111a satisfy the conditional expression (2), the ultraviolet light emitted from each LED die 111a is irradiated It is preferable to set the magnification? In the X-axis direction by the lens 113 and the lens 115 to 3.3 or more (that is, to satisfy the conditional formula (3)) have.

In the present embodiment, the lens 115 of each LED unit 100a is described as being connected in the X-axis direction. However, the lens 115 may be disposed independently of each LED unit 100a.

In the present embodiment, the lens 113 is a spherical convex lens. However, the present invention is not limited to such a configuration. For example, a biconvex lens or a concave-convex lens can be applied.

In the present embodiment, the lens 115 is an aspherical lens having a cylindrical surface and a toroidal surface. However, the present invention is not limited to this configuration. For example, an aspheric lens having a flat surface and a toroidal surface, It is also possible to apply a lens.

In the present embodiment, the lens 113 and the lens 115 are made of silicone resin. However, the present invention is not limited to the silicone resin, and other transparent resin or glass for optical can be applied.

It is also to be understood that the embodiments disclosed herein are illustrative in all respects and are not restrictive. The scope of the present invention is indicated not by the above description, but by the scope of claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

Claims

1. A light irradiation device for irradiating a line-shaped light having a predetermined line width in a second direction extending in a first direction and orthogonal to the first direction, at a predetermined irradiation position on an irradiation surface,
N (N is an integer of 2 or more) light source modules arranged on the substrate at a first interval along the first direction and arranged so as to coincide with the direction of an optical axis in a predetermined direction, And an optical unit which has N optical elements for leading light from each light source module to a predetermined optical path and emits light in a line shape parallel to the first direction with respect to the irradiation surface,
Wherein each of the light source modules comprises M light emitting elements (M is an integer of 2 or more) arranged at a second interval shorter than the first interval along the first direction, and a light emitting portion extending along the first direction have,
Wherein each of the optical elements has a first power in the first direction and a second power different from the first power in the second direction so that light emitted from the light emitting portion is emitted in the first direction at a predetermined magnification And condensing the light in the second direction,
(1), (2) and (3) satisfy the following conditional expressions (1), (2) and (3) when the first interval is a, the length of the light emitting portion in the first direction is b, Investigation device.
? x b? a ... (One)
0.30? B / a? (2)
3.3? (3)

The light irradiation apparatus according to claim 1, wherein the light emitting element is an LED (Light Emitting Diode) having a light emitting surface of a square shape.

2. The optical element according to claim 1, wherein each of the optical elements is arranged in a direction of the optical axis and in a third direction orthogonal to each of the first direction so that the light emitted from the light emitting element is the predetermined line width at the irradiation position And the light converging unit condenses the light emitted from the light emitting element.

The optical element according to claim 2, wherein each of the optical elements is arranged in a direction of the optical axis and in a third direction orthogonal to each of the first direction so that the light emitted from the light emitting element is the predetermined line width at the irradiation position And the light converging unit condenses the light emitted from the light emitting element.

The optical element according to claim 3, wherein each of the optical elements has a first lens through which light from each light source module is incident, and a second lens through which light transmitted through the first lens is incident,
Wherein the first lens has an incident surface formed as a flat surface, a convex surface, or a concave surface, and an exit surface formed as a convex surface,
The second lens is an aspherical lens having an incident surface on which a cylindrical surface having positive power is formed in the third direction and an exit surface on which a troubled surface having a positive power in the first direction and the third direction is formed Characterized in that the light irradiation device

The optical element according to claim 4, wherein each of the optical elements has a first lens through which light from each light source module is incident, and a second lens through which light transmitted through the first lens is incident,
Wherein the first lens has an incident surface formed as a flat surface, a convex surface, or a concave surface, and an exit surface formed as a convex surface,
The second lens is an aspherical lens having an incident surface on which a cylindrical surface having positive power is formed in the third direction and an exit surface on which a troubled surface having a positive power in the first direction and the third direction is formed Characterized in that the light irradiation device

The optical element according to claim 3, wherein each of the optical elements has a first lens through which light from each light source module is incident, and a second lens through which light transmitted through the first lens is incident,
Wherein the first lens has an incident surface formed as a flat surface, a convex surface, or a concave surface, and an exit surface formed as a convex surface,
Wherein the second lens is an aspherical lens having an incident surface formed in a plane and an exit surface in which a troubled surface having a positive power in the first direction and the third direction is formed.

The optical element according to claim 4, wherein each of the optical elements has a first lens through which light from each light source module is incident, and a second lens through which light transmitted through the first lens is incident,
Wherein the first lens has an incident surface formed as a flat surface, a convex surface, or a concave surface, and an exit surface formed as a convex surface,
Wherein the second lens is an aspherical lens having an incident surface formed in a plane and an exit surface in which a troubled surface having a positive power in the first direction and the third direction is formed.

The optical element according to claim 3, wherein each of the optical elements has a first lens through which light from each light source module is incident, and a second lens through which light transmitted through the first lens is incident,
Wherein the first lens has an incident surface formed as a flat surface, a convex surface, or a concave surface, and an exit surface formed as a convex surface,
Wherein the second lens is a spherical double convex lens having an incident surface formed in a convex surface and an emission surface formed in a convex surface.

The optical element according to claim 4, wherein each of the optical elements has a first lens through which light from each light source module is incident, and a second lens through which light transmitted through the first lens is incident,
Wherein the first lens has an incident surface formed as a flat surface, a convex surface, or a concave surface, and an exit surface formed as a convex surface,
Wherein the second lens is a spherical double convex lens having an incident surface formed in a convex surface and an emission surface formed in a convex surface.

11. The light irradiation apparatus according to any one of claims 5 to 10, wherein the second lens has a rectangular outer shape when viewed in the optical axis direction.

The light irradiation apparatus according to claim 11, wherein the second lenses of the respective optical elements are connected along the first direction.

11. The optical pickup device according to any one of claims 1 to 10, wherein the light irradiation device has a plurality of the optical units,
Wherein the plurality of optical units comprise a first optical unit and a second optical unit arranged so as to be shifted relative to the first optical unit in the first direction by a distance of 1/2 of the first distance,
Wherein the first optical unit and the second optical unit are arranged such that the optical path of the light emitted from each of the optical units is symmetrical about the waterline at the irradiation position when viewed in the first direction, Are arranged alternately along the circumference of the light source.

14. The light irradiation apparatus according to claim 11, wherein the light irradiation apparatus has a plurality of the optical units,
Wherein the plurality of optical units comprise a first optical unit and a second optical unit arranged so as to be shifted relative to the first optical unit in the first direction by a distance of 1/2 of the first distance,
Wherein the first optical unit and the second optical unit are arranged such that the optical path of the light emitted from each of the optical units is symmetrical about the waterline at the irradiation position when viewed in the first direction, Are arranged alternately along the circumference of the light source.

13. The light irradiation apparatus according to claim 12, wherein the light irradiation apparatus has a plurality of the optical units,
Wherein the plurality of optical units comprise a first optical unit and a second optical unit arranged so as to be shifted relative to the first optical unit in the first direction by a distance of 1/2 of the first distance,
Wherein the first optical unit and the second optical unit are arranged such that the optical path of the light emitted from each of the optical units is symmetrical about the waterline at the irradiation position when viewed in the first direction, Are arranged alternately along the circumference of the light source.