TWI620889B - Light irradiation device - Google Patents

Abstract

Providing a light that can illuminate a linear light of high intensity Irradiation device.

A light irradiation device that emits linear light having a predetermined line width in a second direction extending in the first direction and orthogonal to the first direction at a predetermined irradiation position on the irradiation surface, the light irradiation device having N (N is an integer of 2 or more) light source module and N optical elements, and has a line of light that is parallel to the first direction on the irradiation surface, and the N light source modules are mounted on the substrate The 1 direction is arranged through the first interval, and the optical axes of the same direction are arranged in a predetermined direction, and the N optical elements are arranged on the optical path of each light source module, and the light from each light source module is guided to a predetermined Each of the light source modules has a light-emitting portion extending along the first direction, and each of the optical elements amplifies the light emitted from the light-emitting portion at a predetermined magnification in the first direction, and sets the first interval to a and the light-emitting portion. When the length in the first direction is set to b and the predetermined magnification is set to α , the following conditional expression (1) is satisfied.

××b≧a‧‧‧(1)

Description

Light irradiation device

The present invention relates to a light irradiation device that illuminates linear irradiation light, and more particularly to a light irradiation device including a plurality of light source modules arranged in a line on a substrate.

Conventionally, an ultraviolet curable ink that is cured by irradiation with ultraviolet light is used as a lithographic single-printing ink. Further, an ultraviolet curable resin is used as a sealing agent for an FPD (Flat Panel Display) such as a liquid crystal panel or an organic EL (Electro Luminescence) panel. In general, in the curing of such an ultraviolet curable ink or an ultraviolet curable resin, an ultraviolet light irradiation device that irradiates ultraviolet light is used, and particularly in the use of lithographic single-chip printing or FPD, it is necessary to irradiate a wide irradiation area. Therefore, a linear light irradiation device that irradiates linear irradiation light is used. Such a linear light irradiation device is described, for example, in Patent Document 1.

The linear light irradiation device disclosed in Patent Document 1 is a so-called LED unit including a rectangular substrate, a plurality of LEDs (Light Emitting Diodes), and a rod lens, and emits line light along the longitudinal direction of the substrate. The plurality of LEDs are along the long side of the substrate Arranged at equal intervals, the rod lens collects light from a plurality of LEDs to the short side direction of the substrate.

In addition, in order to stably and reliably cure the ultraviolet curable ink or the ultraviolet curable resin, it is necessary to have ultraviolet light having high irradiation intensity. Therefore, by using a plurality of LED units described in Patent Document 1, it is possible to form A light irradiation device that irradiates ultraviolet light of high irradiation intensity is also practically used (for example, Patent Document 2).

The light-emitting device described in Patent Document 2 is configured by arranging a plurality of LED units radially (arc-shaped) with respect to the object to be irradiated, and causing the line light emitted from each of the LED units to be at a predetermined position of the object to be irradiated. By overlapping, ultraviolet light having a high linear irradiation intensity is irradiated to the object to be irradiated.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2012-186015

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2010-287547

According to the light irradiation device described in Patent Document 2, since ultraviolet light having an irradiation intensity proportional to the number of LED units can be irradiated, if the ultraviolet light having a high irradiation intensity is desired, the number of LED units is simply increased. can. However, from the physical quantity of the LED unit It is seen that there is a problem that the number of LED units that can be radially arranged is limited. In order to solve the problem, it is conceivable to arrange the LED units away from the object to be irradiated, and when such an arrangement is made, the problem that the entire light irradiation device is increased in size is caused.

Further, as shown in the light irradiation device described in Patent Document 2, when a plurality of LED units are arranged in a radial manner, the incident angles of the line lights emitted from the respective LED units with respect to the object to be irradiated are different. When the incident angle is larger (that is, when the object to be irradiated is obliquely incident), the line width (thickness) of the line light on the object to be irradiated becomes thicker, and the irradiation intensity distribution in the line width direction also becomes It is gentle, and therefore, there is a problem that the desired irradiation intensity cannot be obtained. Since this problem becomes more conspicuous as the number of the LED units arranged in a radial direction increases, there is a demand for suppressing the number of LED units to be used from such a viewpoint.

The present invention has been made in view of such circumstances, and an object thereof is to provide a linear shape capable of emitting high irradiation intensity without increasing the number of LED units (optical units) (that is, without increasing the size of the device). Light illumination device.

In order to achieve the above object, the light irradiation device of the present invention irradiates a predetermined light irradiation position on the irradiation surface with a linear light having a predetermined line width extending in the first direction and in the second direction orthogonal to the first direction. The light irradiation device has N (N is an integer of 2 or more) light source modules and N optical elements, and has a line of light that emits a line parallel to the first direction to the irradiation surface, and the N light source modules. Arranged on the substrate along the first direction via the first interval, and the optical axes in the same direction are arranged in a predetermined direction, and the N optical elements are arranged on the optical path of each light source module, and are supplied from the respective light sources. The light of the module is guided to a predetermined optical path, and each of the light source modules has a light-emitting portion extending along the first direction, and the light-emitting portion has M (M) arranged along the first interval along the first interval. In the light-emitting element of 2 or more integers, each of the optical elements amplifies the light emitted from the light-emitting portion at a predetermined magnification in the first direction, and sets the first interval to a and sets the length of the light-emitting portion in the first direction. to b, the magnification is set to the predetermined α, satisfy the following Piece (1), (2), (3).

××b≧a. . . (1)

0.30≦b/a≦0.42. . . (2)

3.3≦α. . . (3)

According to such a configuration, since the light emitted from each of the light source modules is enlarged in the first direction, a portion of the light emitted from the plurality of light source modules overlaps each other at the irradiation position on the irradiation surface. Therefore, linear light having a high peak intensity is emitted from the optical unit.

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

Further, each of the optical elements may be configured such that light emitted from the light-emitting elements is formed within a predetermined line width at an irradiation position, and is concentrated in a third direction orthogonal to the direction of the optical axis and the first direction. Light emitted from a light-emitting element.

Moreover, each optical element is preferably an aspherical lens, and The aspherical lens has a first lens that receives light from each of the light source modules, and a second lens that emits light that has passed through the first lens, and the first lens has an incident surface, a convex surface, or a concave surface. The second lens system has an entrance surface formed with a cylindrical surface having a positive power in the third direction and an annular surface having a positive power in the first direction and the third direction, and an exit surface formed by the convex surface. Shoot the surface.

Further, it is preferable that each of the optical elements is an aspherical lens having a first lens that enters light from each of the light source modules, and the second lens that emits light that has passed through the first lens, the first The lens system has an incident surface formed by a plane, a convex surface, or a concave surface and an emission surface formed by a convex surface, and the second lens system has an incident surface formed by a plane and has a positive power in the first direction and the third direction. The exit surface of the toroidal surface.

Further, it is preferable that each of the optical elements is a spherical lenticular lens having a first lens that enters light from each of the light source modules, and a second lens that emits light that has passed through the first lens. A lens system has an incident surface formed of a flat surface, a convex surface, or a concave surface, and an emitting surface formed by a convex surface, and the second lens system has an incident surface formed by a convex surface and an emitting surface formed by a convex surface.

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

Further, the light irradiation device includes a plurality of optical units, and the plurality of optical units are constituted by the first optical unit and the second optical unit, and the second optical unit is only at the first interval with respect to the first optical unit. The distance of 1/2 is relatively shifted in the first direction, and when the first optical unit and the second optical unit are viewed from the first direction, the vertical line in the irradiation position can be configured as an axis of symmetry. The optical paths of the light emitted from the optical unit are formed in a line symmetrical manner, and are alternately arranged along a circumference centering on the irradiation position. According to such a configuration, light from the first optical unit and the second optical unit having different irradiation intensity distributions overlaps at the irradiation position, so that linear light having uniform and higher irradiation intensity can be obtained.

As described above, according to the present invention, the light emitted from the plurality of light source modules arranged along the first direction overlaps in the first direction on the irradiation surface, so that the optical unit emits a linear line having a high peak intensity. Light. Therefore, there is provided a light irradiation device which can emit linear light of high irradiation intensity without increasing the number of optical units (that is, without increasing the size of the apparatus).

1‧‧‧Lighting device

10‧‧‧shell

10a‧‧‧ openings

20‧‧‧Base block

100‧‧‧ optical unit

100a, 100b, 100c, 100d, 100e‧‧‧ LED units

110‧‧‧LED module

111‧‧‧LED components

111a‧‧‧LED dies

113, 115‧ ‧ lens

Fig. 1 is an external view of a light irradiation device according to an embodiment of the present invention.

Fig. 2 is an enlarged view showing the configuration and arrangement of an LED unit mounted in a light irradiation device according to an embodiment of the present invention.

Fig. 3 is an enlarged view showing the configuration of the LED unit shown in Fig. 2(a).

Fig. 4 is a cross-sectional view taken along line A-A' of Fig. 3.

Fig. 5 is a cross-sectional view taken along line B-B' of Fig. 3.

Fig. 6 is an enlarged view of a portion A (dashed line) of Fig. 5;

FIG. 7 is a view for explaining a configuration of an LED element of an LED unit mounted in a light irradiation device according to an embodiment of the present invention.

Fig. 8 is a view showing an irradiation intensity distribution in the Y-axis direction of the ultraviolet light emitted from the light irradiation device of the embodiment.

FIG. 9 is a view showing an irradiation intensity distribution in the X-axis direction of the ultraviolet light emitted from the light irradiation device of the embodiment.

FIG. 10 is a view showing the relationship between the length of the light-emitting surface of the LED die mounted on the light-emitting device according to the embodiment of the present invention and the efficiency of the emitted ultraviolet light.

Fig. 11 is a view showing the relationship between the length of the light-emitting surface of the LED crystal chip mounted on the light-emitting device of the embodiment of the present invention and the length of the effective irradiation region.

Fig. 12 is a view showing the relationship between the length of the light-emitting surface of the LED crystal chip mounted on the light-emitting device of the embodiment of the present invention and the peak intensity of the emitted ultraviolet light.

Fig. 13 is a view showing the relationship between the length of the light-emitting surface of the LED crystal chip mounted on the light-emitting device of the embodiment of the present invention and the uniformity of the irradiation intensity distribution of the emitted ultraviolet light.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, the same or equivalent parts in the figures are given the same symbols, and Do not repeat the instructions.

Fig. 1 is an external view of a light irradiation device 1 according to an embodiment of the present invention. The light-emitting device 1 of the present embodiment is mounted on a light source device that cures an ultraviolet-curable ink or an ultraviolet-curable resin, and is disposed above the object to be irradiated as described later, and emits a linear object to the object to be irradiated. Ultraviolet light (Fig. 2(b)), which is used as a lithographic single-printing ink, which is used as a sealant in an FPD (Flat Panel Display) or the like. In the present specification, the long side (line length) direction of the linear ultraviolet light emitted from the light irradiation device 1 is defined as the X-axis direction (first direction), and the short side (line width) direction is defined as the Y-axis. The direction (the second direction) is defined by the direction orthogonal to the X-axis and the Y-axis (that is, the vertical direction) as the Z-axis direction, and will be described. Fig. 1(a) is a front view of the light irradiation device 1 viewed from the Y-axis direction. Fig. 1(b) is a bottom view of the light irradiation device 1 when viewed from the Z-axis direction (when viewed from the lower side to the upper side of Fig. 1(a)). Fig. 1 (c) is a side view of the light irradiation device 1 when viewed from the X-axis direction (when viewed from the right side of Fig. 1 (a) to the left side).

As shown in FIG. 1, the light irradiation device 1 includes a casing 10, a base block 20, and five LED units 100a to 100e. The casing 10 is a casing that houses the base block 20 and the LED units 100a to 100e. Further, the LED units 100a to 100e are units for emitting linear ultraviolet light parallel to the X-axis. In the specification, the LED units 100a to 100e are collectively referred to as "optical unit 100".

The base block 20 is used to fix the support of the optical unit 100 The member 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 the lower surface is formed as a partial cylindrical surface recessed in the Y-axis direction. On the lower surface of the base block 20 (that is, a partial cylindrical surface), LED units 100a to 100e extending in the X-axis direction are arranged along the Y-axis direction (that is, along a partial cylindrical surface), and by Fix it by fixing screws or solder.

The lower surface of the casing 10 (the lower surface of the light irradiation device 1) has an opening 10a, and is configured to emit ultraviolet light from the LED units 100a to 100e toward the object to be irradiated through the opening 10a.

FIG. 2 is an enlarged view showing the configuration and arrangement of the optical unit 100 mounted on the light irradiation device 1 of the present embodiment. 2(a) is an enlarged view of FIG. 1(b). For convenience of explanation, the base block 20 is omitted, and after the optical unit 100 shown in FIG. 1(b) is rotated by 90°, the base block 20 is unfolded in a plane. Part of the cylindrical surface (i.e., extending to the left and right) is indicated. 2(b) is an enlarged cross-sectional view of FIG. 1(c) showing the arrangement of the LED units 100a to 100e when viewed from the X-axis direction.

In the light irradiation device 1 of the present embodiment, the position from the lower end of the casing 10 is away from the lower side (Z-axis direction) by 100 mm (that is, the position of the working distance of 100 mm (in FIG. 2(b), it is expressed as "WD100"). The XY plane in the ")) is used as the reference irradiation surface R, and the irradiation target is transported from the right to the left in the Y-axis direction by a conveyance device (not shown). Further, the objects to be irradiated are sequentially transferred from the right to the left on the irradiation surface R, and are emitted from the LED units 100a to 100e. The ultraviolet light is sequentially moved (scanned) on the object to be irradiated, and the ultraviolet curable ink or the ultraviolet curable resin on the object to be irradiated is sequentially hardened (fixed). In addition, in Fig. 2(b), "F1" indicates a condensing position on the irradiation surface R where the ultraviolet light emitted from the LED units 100a to 100e is collected. Further, in FIG. 2(b), for convenience of explanation, the perpendicular line passing through the irradiation surface R of the condensing position F1 is indicated as the center line O of the optical path of the ultraviolet light emitted from the light irradiation device 1.

As shown in FIG. 2(a), when the light irradiation device 1 of the present embodiment is viewed from the Z-axis direction, the LED units 100a to 100e are sequentially disposed from the right side toward the left side (that is, along the Y-axis). Further, the LED units 100a, 100c, and 100e are arranged to be offset from the LED units 100b and 100d by a distance of P/2 (that is, 1/2 of the arrangement interval P of the LED modules 110) in the X-axis direction.

As shown in Fig. 2(b), the LED units 100a to 100e of the present embodiment are arranged at an angular interval of 10.5° from the circumference of the radius of 125 mm centered on the condensing position F1 when viewed in the X-axis direction. On the arc. Further, in the present embodiment, the LED unit 100c is disposed vertically above the condensing position F1 such that the optical axis of the LED unit 100c substantially coincides with the center line O, and the LED units 100a to 100e are viewed from the X-axis direction. At the time, the center line O is arranged symmetrically with respect to the axis of symmetry. The ultraviolet light from each of the LED units 100a to 100e is configured to be emitted toward the condensing position F1 on the reference irradiation surface R, and to illuminate the reference irradiation surface R with a line width LW centering on the condensing position F1. . Further, in the present embodiment, the line width LW of the ultraviolet light is set to be relative to the poly The light position F1 ± about 20 mm, and the line length LL (length in the X-axis direction) is set to about 100 mm. In the present embodiment, the ultraviolet light from the five LED units 100a to 100e is superimposed on the condensing position F1, and the irradiation target is irradiated with ultraviolet light of high irradiation intensity.

Fig. 3 is a view for explaining the configuration of the LED units 100a to 100e, and Fig. 2(a) is an enlarged view. 4, FIG. 5 and FIG. 6 are views showing the configuration of the inside of the LED units 100a to 100e shown in FIG. 3, FIG. 4 is a cross-sectional view taken along line A-A' of FIG. 3, and FIG. 5 is a view of B- of FIG. B' sectional view, Fig. 6 is an enlarged view of the A portion (dashed line frame) of Fig. 5. In addition, in FIGS. 4, 5, and 6, in order to make the drawing easy to see, a part of the configuration is omitted. In addition, in FIGS. 4, 5, and 6, the optical axis of the ultraviolet light emitted from the LED modules 110 of the LED units 100a to 100e is indicated by a dotted line, and the optical path OP of the ultraviolet light is indicated by a solid line.

Further, since the LED units 100a to 100e of the present embodiment are different only in the respective positions, and the internal configuration is the same, the representative LED unit 100c will be described below.

As shown in Fig. 2(a) and Fig. 3, the LED unit 100c includes a rectangular substrate 101 and ten LED modules 110 extending in the X-axis direction. Ten LED modules 110 are along the X direction. The center line CL ( FIG. 3 ) of the substrate 101 extending in the axial direction is densely arranged on the substrate 101 and electrically connected to the substrate 101 . The substrate 101 of the LED unit 100c is connected to an LED drive circuit (not shown), and the drive current from the LED drive circuit is supplied to each of the LED modules 110 via the substrate 101.

When the driving current is supplied to each of the LED modules 110, from each of the LED modules The group 110 emits ultraviolet light in response to the amount of light of the driving current, and emits linear ultraviolet light parallel to the X-axis from each of the LED units 100c. Further, as will be described later, each of the LED modules 110 of the present embodiment includes an LED element 111 (FIG. 3) in which four LED (Light Emitting Diode) crystal grains 111a are housed, and is emitted from each of the LED dies 111a. The driving current supplied to each of the LED modules 110 (that is, the respective LED dies 111a) is adjusted in such a manner that the ultraviolet light of the irradiation intensity distribution is equal. Further, the linear 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). Further, as shown in Fig. 2 (a) and Fig. 3, the arrangement interval P of each of the LED modules 110 of the present embodiment is equal to the size of the package 111p of the LED element 111 to be described later, and is set in the present embodiment. It is about 14mm.

As shown in FIGS. 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 showing 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 line C-C' of Fig. 7(a). As shown in FIG. 7, the LED element 111 of the present embodiment includes a square package 111p having four LED dies 111a (light-emitting elements) built therein. Further, the opening of the package 111p is sealed by the cover glass 111c. The LED chip 111a includes a semiconductor element having a substantially square light-emitting surface and receiving a supply of a drive current from the LED drive circuit to emit ultraviolet light having a wavelength of 365 nm. In the present embodiment, each of the LED dies 111a is provided with a light-emitting surface of 0.85 × 0.85 mm and along the center line of the package 111p (also That is, the center line parallel to the side opposite to the one set is arranged at intervals of 1.2 mm. Each of the LED elements 111 is mounted on the substrate 101 such that the LED dies 111a are arranged in 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 disposed on the optical axis of each of the LED elements 111. The lens 113 is formed by, for example, injection molding of a silicone resin, for example, a spherical plano-convex lens having a planar side of the LED element 111, and diffusing from each of the LED dies 111a, and simultaneously collecting the incident ultraviolet light to be guided to the rear stage. Lens 115. The lens 115 is an aspherical lens formed by injection molding of a silicone resin, and is provided with an incident surface having a cylindrical surface having a power in the Y-axis direction and having a different power in the Y-axis direction and the X-axis direction. The exit surface of the annular surface collects ultraviolet light incident from the lens 113 in the Y-axis direction, and is amplified at a predetermined magnification (for example, about 10 times) in the X-axis direction. Therefore, as viewed in the X-axis direction, the ultraviolet light emitted from each of the LED elements 111 (that is, the LED dies 111a) is collected by the lens 113 and the lens 115 to the condensing position F1. Further, as shown in FIG. 5, when viewed in the Y-axis direction, the ultraviolet light emitted from each of the LED elements 111 is diffused in the X-axis direction by the lens 113 and the lens 115, and is configured to be on the irradiation surface R and other components. The ultraviolet light of the LED element 111 overlaps each other. Further, in the present embodiment, the lens 113 is a lens having a maximum diameter of φ 13.5 mm in a direction orthogonal to the optical axis. Further, the lens 115 is a lens having a rectangular cross section in a direction orthogonal to the optical axis. In the present embodiment, the lens 115 of each LED unit 100a is connected to the X-axis direction, and is configured as one member. With a composition like this, The ultraviolet light incident from each of the LED dies 111a is guided to the irradiation surface R by the efficiency (i.e., the halation caused by the lens 113 and the lens 115 does not occur).

In the present embodiment, the ultraviolet light emitted from each of the LED elements 111 is superposed on the irradiation surface R so as to overlap each other in the X-axis direction, thereby forming a high-intensity (peak intensity) ultraviolet light. Light is emitted from each of the LED units 100a to 100e. In other words, each of the LED units 100a to 100e is formed to emit ultraviolet light having a peak intensity higher than that of the conventional LED unit (for example, described in Patent Document 2). In the light-emitting device 1 of the present embodiment, the five LED units 100a to 100e configured as described above are used, and the ultraviolet light from the LED units 100a to 100e is superimposed on the condensing position F1. The object illuminates a higher intensity of ultraviolet light.

FIG. 8 is a view showing an irradiation intensity distribution in the Y-axis direction of the ultraviolet light emitted from the light irradiation device 1 of the present embodiment, and shows the center position of the light irradiation device 1 in the longitudinal direction (that is, ultraviolet light). The irradiation intensity distribution in the Y-axis direction in the line length LL (the position of 1/2 of the length in the X-axis direction). Fig. 8(a) shows the irradiation intensity distribution of the ultraviolet light emitted from each of the LED units 100a to 100e, and Fig. 8(b) shows the total irradiation intensity distribution of the ultraviolet light emitted from the five LED units 100a to 100e. Comparing Fig. 8 (a) and (b), it is known that the ultraviolet light from the five LED units 100a to 100e is superposed on the condensing position F1, and the condensing position F1 can be obtained (in Fig. 8, "0 mm" It is shown that ultraviolet light having a peak intensity of ultraviolet light emitted from each of the LED units 100a to 100e (a peak intensity of about 8000 mW/cm ² ) is obtained.

FIG. 9 is a view showing an irradiation intensity distribution in the X-axis direction of the ultraviolet light emitted from the light irradiation device 1 of the present embodiment, and shows the center position in the short-side direction of the light irradiation device 1 (that is, the condensing position). The intensity distribution of the X-axis direction in F1). Fig. 9(a) shows the irradiation intensity distribution of the ultraviolet light emitted from the LED units 100a, 100c, and 100e, respectively, and Fig. 9(b) shows the irradiation intensity of the ultraviolet light emitted from the LED units 100b and 100d. Distribution, Fig. 9(c) shows the total irradiation intensity distribution of the ultraviolet light emitted from the five LED units 100a to 100e. In addition, in FIGS. 9(a) and 9(b), for the sake of convenience of explanation, the irradiation intensity distribution of the ultraviolet light emitted from each of the LED elements 111 of the LED units 100a to 100e is indicated by a solid line, and the dotted line indicates the The intensity distribution of the ultraviolet light emitted from the entire LED unit (that is, the sum of the ultraviolet light emitted from each of the LED elements 111).

As described above, the ultraviolet light emitted from each of the LED elements 111 of the present embodiment is diffused in the X-axis direction by the lens 113 and the lens 115, and is irradiated onto the irradiation surface R. Here, the ultraviolet light emitted from each of the LED elements 111 is different from the ultraviolet light emitted from the four LED dies 111a arranged at equal intervals along the X-axis direction, and therefore, the LED elements are not included. The irradiation intensity distribution in the X-axis direction of the ultraviolet light emitted from 111 is formed as a discontinuous irradiation intensity distribution having four peaks. Further, the ultraviolet light having the discontinuous irradiation intensity distribution is diffused to the X-axis direction by the lens 113 and the lens 115 at a predetermined magnification, and is irradiated onto the irradiation surface R (Fig. 9(a) and Fig. 9). (b) the solid line). Its knot On the irradiation surface R, the ultraviolet light from the plurality of LED elements 111 overlaps in the X-axis direction and can be at the center position in the longitudinal direction of the light irradiation device 1 (that is, the line length LL of the ultraviolet light ( Increasing the irradiation intensity (the position of 1/2 of the length in the X-axis direction) is a predetermined range (in the present embodiment, the range is about 35 mm) (Fig. 9 (a) and Fig. 9 (b) Dotted line). As described above, in the present embodiment, ultraviolet light having a high peak intensity is obtained by superimposing ultraviolet light from a plurality of LED elements 111 arranged in the X-axis direction in the X-axis direction. In the present specification, a portion in which ultraviolet light is superimposed and the peak intensity is increased is referred to as an "effective irradiation region", and in the present embodiment, the irradiation target is disposed in the portion.

Further, as shown in FIGS. 9(a) and 9(b), the irradiation intensity distribution of the ultraviolet light emitted from each of the LED units 100a to 100e can increase the peak intensity in the effective irradiation region, but some of them are formed into teeth. Change (ie, uneven). This is because the density of the LED dies 111a arranged in the X-axis direction is not fixed, and a portion where the LED dies 111a are not disposed exists between the respective LED elements 111. Therefore, in the present embodiment, the illumination intensity distribution of the ultraviolet light emitted from the entire light irradiation device 1 is formed to be substantially uniform, and the LED units 100a, 100c, and 100 are only P with respect to the LED units 100b and 100d. The distance of /2 (that is, 1/2 of the arrangement interval P of the LED module 110) is shifted in the X-axis direction. When the LED units 100a to 100e are arranged in this manner, the portions of the ultraviolet light emitted from the respective LED units 100a to 100e whose illumination intensity is lowered are canceled on the irradiation surface R. Therefore, the irradiation intensity distribution of the ultraviolet light as the entire light irradiation device 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-axis direction. Further, a peak intensity of 5 times (about 8000 mW/cm ² ) of the peak intensity of the ultraviolet light emitted from each of the LED units 100a to 100e is formed.

In each of the LED units 100a to 100e of the present embodiment, a plurality of (10) LED elements 111 including a plurality of (four) LED dies 111a are arranged in the X-axis direction, and The ultraviolet light emitted from each of the LED elements 111 is amplified in the X-axis direction, and ultraviolet light having a high peak intensity is emitted. That is, ultraviolet light having a high peak intensity is emitted from each of the LED units 100a to 100e. Further, the LED units 100a to 100e are arranged such that the ultraviolet light from the five LED units 100a to 100e is collected on the condensing position F1 on the irradiation surface R, thereby further increasing the peak intensity and uniformly emitting the light. The intensity of the ultraviolet light is distributed. Therefore, according to the light irradiation device 1 configured as described above, the ultraviolet curable ink or the ultraviolet curable resin on the object to be irradiated can be stabilized and cured (fixed).

Although the present embodiment has been described above, the present invention is not limited to the above-described configuration, and various modifications can be made without departing from the spirit and scope of the invention.

For example, although the light irradiation device 1 of the present embodiment is provided with five LED units 100a to 100e, as described above, ultraviolet light having a high peak intensity is emitted in each of the LED units 100a to 100e. Adjust the desired peak intensity The number of LED units may be sufficient, and the light irradiation device 1 may be provided with one or more LED units.

Further, although each of the LED units 100a to 100e of the present embodiment has been provided with ten LED modules 110, the ultraviolet light emitted from the LED module 110 is less on the irradiation surface R. Since the peak intensity of the ultraviolet light can be increased by overlapping, the LED units 100a to 100e are required to have at least two or more LED modules 110 in the X-axis direction.

In addition, the LED element 111 of the present embodiment has a light-emitting surface of 0.85 × 0.85 mm, and four LED dies 111a arranged at intervals of 1.2 mm in the X-axis direction, but the size of the light-emitting surface and the LED dies are described. The number of 111a and the interval of the LED dies 111a are not necessarily limited to those of such a configuration. In other words, when the ultraviolet light emitted from the LED element 111 is amplified in the X-axis direction, it is improved even if the ultraviolet light from the other LED elements 111 (for example, the adjacent LED elements 111) is small. Since the peak intensity of the ultraviolet light is sufficient, the LED element 111 can emit ultraviolet light extending in the X-axis direction, and for example, one light-emitting surface extending in the X-axis direction (that is, one LED crystal can be applied). The particles 111a) are substituted for a plurality of LED dies 111a. Further, in this case, the size (length) of the light-emitting surface corresponds to the length of the light-emitting portion constituted by the plurality of LED dies 111a of the present embodiment (that is, the region in which the plurality of LED dies 111a are disposed) The length in the X-axis direction), taking into consideration the size of the lens 113 and the lens 115 used, the length of the effective irradiation region, the peak intensity of the desired ultraviolet light, the uniformity of the desired ultraviolet light irradiation intensity distribution, and the like. Make settings as appropriate. However, in order to cause the ultraviolet light emitted from one LED element 111 to be amplified in the X-axis direction and overlap with the ultraviolet light from the other LED elements 111, the interval between the LED elements 111 is a, and the X-axis of the light-emitting surface is used. When the length of the direction is b and the magnification of the lens 113 and the lens 115 in the X-axis direction is α , the following conditional expression (1) is satisfied.

××b≧a. . . (1)

10 to 13 are diagrams showing the results of simulations performed by the inventors in order to obtain the length of the light-emitting surface (light-emitting portion) of the LED crystal 111a. Fig. 10 is a graph showing the relationship between the length (light-emitting length) of the light-emitting surface of the LED chip 111a and the efficiency of the emitted ultraviolet light. Here, the efficiency of the emitted ultraviolet light means the efficiency of the ultraviolet light emitted from the LED die 111a, and is defined herein as (the amount of ultraviolet light on the irradiation surface R) / (from the LED) The amount of ultraviolet light emitted by the crystal grains 111a). Further, Fig. 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 region.

Fig. 12 is a graph showing the relationship between the length of the light-emitting surface of the analog LED die 111a and the peak intensity of the emitted ultraviolet light. Fig. 13 is a graph showing the relationship between the length of the light-emitting surface of the analog LED die 111a and the uniformity of the irradiation intensity distribution of the emitted ultraviolet light. The uniformity of the intensity distribution of the emitted ultraviolet light refers to the deviation of the irradiation intensity in the effective irradiation region, and is defined as (the maximum intensity in the effective irradiation region) in the present specification. Degree) - (minimum intensity in the effective irradiation area) / ((maximum intensity in the effective irradiation area) + (minimum intensity in the effective irradiation area)). Further, in the simulation shown in FIGS. 10 to 13, the lens 113 and the lens 115 which are the same as those in the present embodiment are disposed on the optical path of the LED element 111, and the LED modules 110 (that is, the LED elements 111) are disposed. The arrangement interval P is also set to be 14 mm as in the present embodiment, and simulation is performed.

As shown in FIG. 10, when the length (light emission length) of the light-emitting surface of the LED chip 111a becomes long, the efficiency of the emitted ultraviolet light gradually decreases. This is because, by lengthening the light-emitting surface of the LED die 111a, halation caused by the lens 113 and the lens 115 occurs (that is, a part of the ultraviolet light emitted from the light-emitting surface is not taken. Into the lens 113 and the lens 115). Therefore, when the efficiency ≧75% is set as the target value, when the lens 113 and the lens 115 of the present embodiment are used, the length of the light-emitting surface of the LED chip 111a is preferably 5.8 mm or less.

As shown in FIG. 11, when the length (light-emitting length) of the light-emitting surface of the LED chip 111a becomes long, the length of the effective irradiation region (the effective irradiation region length) is gradually shortened. This is because when the luminescence length is increased, the overlap of the ultraviolet light is increased in the center portion of the effective irradiation region, so that the peak intensity is increased. On the other hand, the irradiation intensity at the both end sides of the effective irradiation region is relatively large. The ground is falling. 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 chip 111a is preferably 5.8 mm or less.

As shown in FIG. 12, when the length (light-emitting length) of the light-emitting surface of the LED chip 111a becomes long, the peak intensity of the emitted ultraviolet light increases. Big. This is because the length on the irradiation surface R of the ultraviolet light irradiated from each of the LED dies 111a becomes long, and the length of the ultraviolet light superposed in the X-axis direction also becomes long. Therefore, when the peak intensity of ultraviolet light ≧600 mW is set to a target value, it is preferable that the length of the light-emitting surface of the LED chip 111a is 4.2 mm or more.

As shown in FIG. 13, the uniformity of the emitted ultraviolet light changes depending on the length (light emission length) of the light-emitting surface of the LED die 111a. Therefore, when the uniformity of the irradiation intensity distribution of ultraviolet light ≦ 7% is set as the target value, the length of the light-emitting surface of the LED crystal 111a is preferably 4.2 mm or more.

From the above simulation results, the length of the light-emitting surface of the LED die 111a (b) is considered in consideration of the efficiency of the ultraviolet light, the length of the effective irradiation region, the peak intensity of the ultraviolet light, and the uniformity of the irradiation intensity distribution of the ultraviolet light. It is preferable to set the range of 4.2 mm to 5.8 mm. When the interval (a) of the LED element 111 of the present embodiment is 14 mm, the following conditional expression (2) can be obtained from the conditional expression (1).

0.30≦b/a≦0.42. . . (2)

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

Further, from the conditional expression (1) and the conditional expression (2), the following conditional expressions (3) and (4) can be obtained.

3.3≦α. . . (3)

2.3≦α. . . (4)

In other words, it is known that the interval (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), so that the ultraviolet light irradiated from each of the LED dies 111a is on the irradiation surface. It is preferable to set the magnification ( α ) of the lens 113 and the lens 115 in the X-axis direction to 3.3 or more (that is, satisfy the conditional expression (3)).

Further, in the present embodiment, it has been described that the lens 115 of each of the LED units 100a is connected to the X-axis direction, but the lens 115 may be disposed separately from each of the LED units 100a.

In the present embodiment, the lens 113 is a spherical plano-convex lens. However, the lens 113 is not limited to such a configuration. For example, a lenticular lens or a meniscus lens may be applied.

Further, in the present embodiment, the lens 115 is an aspherical lens in which a cylindrical surface and a circular surface are formed. However, the configuration is not limited to such a configuration. For example, an aspheric surface in which a flat surface and a circular surface are formed may be applied. Lens, spherical lenticular lens.

In the present embodiment, the lens 113 and the lens 115 are formed of a silicone resin. However, the lens 113 and the lens 115 are not limited to those of the epoxy resin. For example, other optical transparent resins or glass may be used.

In addition, in the embodiment disclosed herein, all the points are exemplified, and it is considered that it is not limited. The scope of the present invention is not described above, but is represented by the scope of the patent application, including The scope of the benefit is equivalent to all changes in the meaning and scope.

Claims (9)

A light irradiation device that irradiates a predetermined irradiation position on an irradiation surface with a linear light having a predetermined line width extending in a first direction and in a second direction orthogonal to the first direction, the light irradiation device The present invention has N (N is an integer of 2 or more) light source modules and N optical elements, and includes light that emits linear light parallel to the first direction to the irradiation surface, and the N light source modules. Arranging on the substrate along the first direction at a first interval, and arranging optical axes in the same direction in a predetermined direction, the N optical elements are disposed on the optical path of each of the light source modules, and will be from The light of each of the light source modules is guided to a predetermined optical path, and each of the light source modules has a light-emitting portion extending along the first direction, and the light-emitting portions are arranged along a first interval along the first direction. In the light-emitting element of M (M is an integer of 2 or more), each of the optical elements amplifies the light emitted from the light-emitting portion at a predetermined magnification in the first direction, and sets the first interval to a and The length of the first direction of the light-emitting portion Set to b, the magnification is set to the predetermined α, satisfies the following conditional formula (1), (2), (3), α × b ≧ a. . . (1) 0.30≦b/a≦0.42. . . (2) 3.3≦α. . . (3). The light-emitting device according to claim 1, wherein the light-emitting element is an LED (Light Emitting Diode) having a substantially square light-emitting surface. The light-emitting device according to claim 1 or 2, wherein each of the optical elements is such that light emitted from the light-emitting element is formed within the predetermined line width at the irradiation position, and The direction of the optical axis and the third direction orthogonal to the first direction collect light emitted from the light-emitting element. The light-emitting device of claim 3, wherein each of the optical elements includes: a first lens that receives light from each of the light source modules; and a second lens that transmits and transmits the first lens The first lens has an incident surface formed by a plane, a convex surface, or a concave surface, and an emission surface formed by a convex surface, and the second lens-based aspherical lens has a positive shape formed in the third direction. The incident surface of the cylindrical surface of the power and the exit surface of the annular surface having a positive power in the first direction and the third direction are formed. The light-emitting device of claim 3, wherein each of the optical elements includes: a first lens that receives light from each of the light source modules; and a second lens that transmits and transmits the first lens The first lens has an incident surface formed by a plane, a convex surface, or a concave surface, and an emission surface formed by a convex surface, and the second lens aspherical lens has an incident surface formed by a plane and An exit surface having an annular surface having a positive power is formed in the first direction and the third direction. The light irradiation device of claim 3, wherein each of the optical elements has a first lens, and the injection is from the foregoing The light of each of the light source modules; and the second lens is incident on the light transmitted through the first lens, and the first lens has an incident surface formed by a plane, a convex surface, or a concave surface, and an emission surface formed by the convex surface. The second lens-based spherical lenticular lens has an incident surface formed by a convex surface and an emitting surface formed by a convex surface. The light irradiation device according to any one of claims 4 to 6, wherein the second lens has a rectangular outer shape when viewed from the optical axis direction. The light irradiation device of claim 7, wherein the second lens of each of the optical elements is coupled along the first direction. The light irradiation device according to any one of claims 4 to 6, wherein the light irradiation device includes a plurality of the optical units, and the plurality of optical units are the first optical unit and the second optical unit. In the unit, the second optical unit is disposed to be relatively offset from the first optical unit by a distance of 1/2 of the first interval toward the first direction, and the first optical unit and the second unit The optical unit is alternately arranged along a circumference centering on the irradiation position when viewed in the first direction, so that an optical path of light emitted from each of the optical units forms a perpendicular line in the irradiation position as an axis of symmetry. Line symmetry.