JP2015106700A - Light irradiation apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light irradiation apparatus capable of irradiating an outer peripheral surface of a drum with ultraviolet light of a plurality of wavelengths whose peak intensities are aligned.SOLUTION: A light irradiation apparatus, which irradiates a sheet-like irradiation target moving along a part of an outer peripheral surface of a cylindrical drum in a closely contact manner with light, comprises a plurality of optical units which have: a light source part which consists of a plurality of light-emitting elements arranged on a substrate along a first direction and a second direction; and a pair of rectangular reflection mirrors which is arranged so as to sandwich optical axes of the plurality of light-emitting elements from the second direction, guide light from the light source part by a pair of reflection mirrors, and emit light of a predetermined spread angle and light quantity to the drum. The plurality of optical units consist of N×M pieces (M denotes an integer of 1 or more) of optical units which emit N types (N denotes an integer of 2 or more) of light having different wavelengths, each emission surface of N×M pieces of the optical units is arranged on a predetermined reference plane, and a distance between the pair of reflection mirrors of each optical unit is set based on a distance from a reference plane of the optical axis to the outer peripheral surface of the drum.

Description

  The present invention is a light irradiation device that irradiates light to a sheet-like irradiation object that moves in close contact along a part of the outer peripheral surface of a cylindrical drum, and in particular, can irradiate light having a plurality of different wavelengths. The present invention relates to a light irradiation apparatus.

  Conventionally, an ultraviolet curable resin has been widely used to form a predetermined pattern or fine structure on a glass substrate, a plastic substrate, or a film substrate. Such an ultraviolet curable resin is designed to be cured by, for example, irradiation with ultraviolet light having a wavelength of around 365 nm. For curing of the ultraviolet curable resin, a light irradiation device that irradiates ultraviolet light (so-called ultraviolet irradiation device) is used. Used.

  An example of a technique for forming a fine structure on a substrate is a nanoimprint method. The nanoimprint method is very excellent in generating a nano-sized fine structure pattern on the substrate surface. In particular, from the viewpoint of mass productivity and releasability, a roll-shaped mold is used to transfer and reproduce the fine structure pattern. A configuration to use is proposed. A pattern forming apparatus having such a configuration is described in Patent Document 1, for example.

  In the pattern forming apparatus described in Patent Document 1, a film having a surface coated with an ultraviolet curable resin is wound around a roll-shaped mold having a fine structure pattern formed on the outer peripheral surface, and the light irradiation device is applied to the outer peripheral surface of the mold. On the other hand, after the resin is cured by irradiating with ultraviolet light, the fine structure pattern is continuously (repetitively) transferred onto the film by being separated from the mold.

  Since the transfer quality of the fine structure pattern obtained by such a method is determined by the resin curing process using ultraviolet light, in order to improve the transfer quality (that is, to obtain an accurate fine structure pattern), a film It is required to cure the resin surely when it is in close contact with the mold. Therefore, in order to cure the resin more reliably, a configuration in which ultraviolet light having a plurality of wavelengths is irradiated has been proposed (for example, Patent Document 2).

  The pattern forming apparatus described in Patent Document 2 is an apparatus in which an ultraviolet curable resin is applied in a line shape on a substrate and is cured by ultraviolet light. First, only the surface portion of the resin is irradiated by irradiating ultraviolet light with a short wavelength. Next, the resin coated in a line is surely cured by irradiating ultraviolet light having a long wavelength that easily penetrates into the resin to cure the interior of the resin.

JP 2013-086388 A JP 2012-143691 A

  When a fine structure pattern is generated by a roll-shaped mold (that is, a drum) as in the pattern forming apparatus described in Patent Document 1, it is necessary to appropriately change the mold itself according to a desired fine structure pattern and a film to be used. There is. Therefore, in order to be able to attach molds having various outer diameters and to secure a space for mold replacement work, a light irradiation device having a flat light emission surface facing the outer peripheral surface of the mold is required.

  Accordingly, when the configuration described in Patent Document 2 (that is, the configuration in which ultraviolet light having a plurality of wavelengths is irradiated) is applied to the pattern forming apparatus described in Patent Document 1, an optical unit that emits ultraviolet light having different wavelengths. It is desirable to arrange them flat on the outer peripheral surface of the mold.

  However, if optical units with different wavelengths are arranged flat with respect to the outer peripheral surface of the mold, the distance from each optical unit to the mold will be different, and the resin on the mold will have ultraviolet light with different peak intensity for each wavelength. Is incident. In this way, when ultraviolet light with different peak intensities for each wavelength is incident on the resin, the curing of the resin is affected by the ultraviolet light with low peak intensity, and the fine structure pattern is not accurately transferred. There was a problem that the reliability of the remarkably deteriorated. It is also possible to improve the transfer quality by slowing the transfer speed and increasing the integrated light amount in accordance with the ultraviolet light having a low peak intensity. However, this method has a problem that the production efficiency is remarkably lowered. there were.

  The present invention has been made in view of such circumstances, and an object thereof is to arrange optical units that emit ultraviolet light of different wavelengths in a flat manner with respect to the outer peripheral surface of a mold (that is, a drum). It is to provide a light irradiation apparatus that can emit ultraviolet light having a uniform peak intensity between wavelengths while adopting the above-described configuration.

  In order to achieve the above object, the light irradiation apparatus of the present invention is a light irradiation apparatus that irradiates light to a sheet-like irradiation object that moves in close contact along a part of the outer peripheral surface of a cylindrical drum, On the substrate, n (n is an integer of 2 or more) at a first predetermined interval along a first direction parallel to the central axis of the drum, and a second along a second direction orthogonal to the first direction. A light source unit composed of a plurality of light emitting elements arranged in m rows (m is an integer equal to or greater than 1) at a predetermined interval and arranged in a third direction orthogonal to the substrate surface with the optical axes aligned; A pair of rectangular reflecting mirrors extending in the first direction and the third direction so as to sandwich the optical axis of the light emitting element from the second direction and arranged so that the reflecting surfaces face each other, and light from the light source unit Is guided by a pair of reflecting mirrors, and emits light with a predetermined divergence angle and light quantity to a part of the outer peripheral surface of the drum. A plurality of optical units, and each of the plurality of optical units includes N × M (M is an integer of 1 or more) optical units that emit light of N types (N is an integer of 2 or more). The exit surfaces of the × M optical units are arranged on a predetermined reference plane defined by the first direction and the second direction, and the distance between the pair of reflecting mirrors of each optical unit is the optical axis. It is set based on the distance from the reference plane to the outer peripheral surface of the drum.

  According to such a configuration, N × M optical units are arranged flat with respect to the outer peripheral surface of the drum, but the distance between the pair of reflecting mirrors of each optical unit is the reference plane of the optical axis. Therefore, it is possible to emit ultraviolet light having uniform peak intensities among the N types of wavelengths.

Also, among the N × M optical units, the optical unit having the longest distance from the reference plane of the optical axis to the outer peripheral surface of the drum is set as the first optical unit, and the first optical unit in order along the second direction. , The distance between the pair of reflecting mirrors of the i-th optical unit (i is an integer of 1 to N × M) is defined as a _i , and the optical axis reference The distance from the plane to the outer peripheral surface of the drum is b _i , the size of the light source part in the second direction is c, the distance between the reflecting mirrors located at both ends in the second direction is d, and the diameter of the drum is e. Sometimes it is desirable to satisfy the following expressions (1), (2) and (3).

a _i > c (1)
a _i × b _i = k (k is a predetermined constant) (2)
d <e (3)

Also, among the N × M optical units, the optical unit having the longest distance from the reference plane of the optical axis to the outer peripheral surface of the drum is set as the first optical unit, and the first optical unit in order along the second direction. To the N × M-th optical unit, the first and N × M-th optical units extend substantially parallel to the vicinity of the outer peripheral surface of the drum from the tip of each reflecting mirror located at both ends in the second direction. a pair of extension mirrors for reflecting the light emitted from the optical unit respectively, the distance between a pair of reflecting mirrors of the first optical unit and a _1, a reference plane of the optical axis of the first optical unit The distance from the outer peripheral surface of the drum to b ₁ is b ₁ , the distance between the pair of reflecting mirrors of the N × Mth optical unit is a _{(N × M),} and the optical axis of the N × Mth optical unit is The distance from the reference plane to the outer peripheral surface of the drum And _{(N × M),} the i-th (i is 2 or more (N × M-1) an integer) the distance between the pair of reflecting mirrors of the optical unit and a _i, of the i-th optical unit The distance from the reference plane of the optical axis to the outer peripheral surface of the drum is b _i , the size of the light source section in the second direction is c, the distance between the reflecting mirrors located at both ends in the second direction is d, and the diameter of the drum It is desirable to satisfy the following expressions (4), (5) and (6), where e is e.

a ₁ , a _{(N × M)} , a _i > c (4)
_{a 1 × b 1/2 =} a (N × M) × b (N × M) / 2 = a i × b i = k (k is a predetermined constant)
... (5)
d ≦ e (6)

  In addition, it is desirable that the emission surfaces of the N × M optical units are arranged at equal intervals along the second direction.

  In addition, the N × M optical units are arranged in groups for each wavelength so that the irradiation object receives light from a short wavelength to a long wavelength in order as the irradiation object moves. It is desirable that According to such a structure, when the ultraviolet curable resin is apply | coated to the surface of the irradiation target object, the inside can be hardened after hardening the surface of the said ultraviolet curable resin.

  The plurality of light emitting elements are LEDs (Light Emitting Diodes) having a substantially square light emitting surface, and it is desirable that the two sides of the light emitting surface are arranged in parallel to the first direction.

  The plurality of light emitting elements are LEDs having a substantially square light emitting surface, and it is desirable that one diagonal line of the light emitting surface is parallel to the first direction. According to such a configuration, the light emitted from the LED and the light emitted from the LED adjacent to the LED overlap each other in the first direction and the second direction. Distribution is obtained.

  In addition, m is 2 or more, and among the plurality of light emitting elements, the light emitting elements in the second column in the second direction (v is an integer of 1 to (m−1)) are in the (v + 1) th column. It is desirable that the light emitting elements are arranged so as to be shifted in the first direction by a distance that is ½ of the first predetermined interval. According to such a configuration, each line-shaped light in the v-th column and each line-shaped light in the (v + 1) -th column cancel each other partially in the light amount distribution, so that the first direction on the irradiation object A substantially uniform light amount distribution can be obtained.

  Further, it is desirable that the light emitting element has at least one LED chip.

  Moreover, it is desirable that the light of N different wavelengths is light including a wavelength that acts on the ultraviolet curable resin applied to the surface of the irradiation object.

  In addition, it is desirable that each of the pair of reflection mirrors has a rectangular shape when viewed from the second direction.

  As described above, according to the light irradiation device of the present invention, the optical units that emit ultraviolet light having different wavelengths are arranged flat with respect to the outer peripheral surface of the drum, but the peak intensity between the wavelengths is high. It is possible to emit uniform ultraviolet light to the drum.

It is a front view of the light irradiation apparatus which concerns on the 1st Embodiment of this invention. It is a left view of the light irradiation apparatus which concerns on the 1st Embodiment of this invention. It is an enlarged view of the area | region shown by A of FIG. It is a figure explaining the relationship between the ultraviolet light radiate | emitted from the light irradiation apparatus which concerns on the 1st Embodiment of this invention, and the irradiation area | region of a drum. It is a graph which shows intensity distribution on the drum of the ultraviolet light radiate | emitted from the light irradiation apparatus which concerns on the 1st Embodiment of this invention. It is a figure explaining the relationship between the ultraviolet light radiate | emitted from the light irradiation apparatus which concerns on the 1st Embodiment of this invention, and the irradiation area | region of a drum. It is a graph which shows intensity distribution on the drum of the ultraviolet light radiate | emitted from the light irradiation apparatus which concerns on the 1st Embodiment of this invention. It is a left view explaining the structure of the light irradiation apparatus which concerns on the 2nd Embodiment of this invention. It is a graph which shows intensity distribution on the drum of the ultraviolet light radiate | emitted from the light irradiation apparatus which concerns on the 2nd Embodiment of this invention. It is a figure explaining the structure of the 1st LED unit, 2nd LED unit, and 3rd LED unit with which the light irradiation apparatus which concerns on the 3rd Embodiment of this invention is equipped. It is a figure explaining the structure of the 1st LED unit, 2nd LED unit, and 3rd LED unit with which the light irradiation apparatus which concerns on the 4th Embodiment of this invention is equipped.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, the same code | symbol is attached | subjected to the same or an equivalent part in a figure, and the description is not repeated.

(First embodiment)
FIG. 1 is a front view of a light irradiation apparatus 100 according to the first embodiment of the present invention. FIG. 2 is a left side view of the light irradiation apparatus 100 according to the first embodiment of the present invention. FIG. 3 is an enlarged view of a region indicated by A in FIG. The light irradiation apparatus 100 of this embodiment is an apparatus that is incorporated in a pattern forming apparatus or the like (hereinafter referred to as “main body apparatus”) and cures an ultraviolet curable resin applied to the surface of an irradiation target, which will be described later. As described above, the sheet-shaped irradiation object that moves in close contact along a part of the outer peripheral surface of the drum disposed in the main body device is irradiated with light. The drum arranged in the main unit is configured to be replaceable according to a desired fine structure pattern and characteristics / specifications of a film to be used. As shown in FIG. The sheet-shaped irradiation object P1 moving in close contact along the large-diameter drum D1 and the sheet-shaped irradiation object P2 moving in close contact along the small-diameter drum D2 are irradiated with light. As shown in FIG. 2, in the present embodiment, the irradiation objects P1 and P2 move on the large-diameter drums D1 and D2 in the direction of the arrow (that is, counterclockwise) at a constant speed. This will be described below. In the present specification, the large-diameter drum D1 and the small-diameter drum D2 are collectively referred to as “drums”, and the irradiation objects P1 and P2 are collectively referred to as “irradiation objects”.

  As shown in FIGS. 1-3, the light irradiation apparatus 100 includes a rectangular substrate 101 extending in parallel along the central axis O1 (not shown in FIG. 1) of the large diameter drum D1 and the central axis O2 of the small diameter drum D2. The first LED (Light Emitting Diode) unit 110, the second LED unit 120, the third LED unit 130, and the cover glass 105, which are arranged on the substrate 101 at equal intervals and emit linear ultraviolet light respectively. Yes. In the actual light irradiation apparatus 100, the substrate 101, the first LED unit 110, the second LED unit 120, the third LED unit 130, and the cover glass 105 are housed and fixed in a case (not shown). In FIGS. 1 to 3, cases are omitted to make the drawings easier to see. In the present specification, the longitudinal direction of the substrate 101 of the light irradiation apparatus 100 is the X-axis direction (first direction), the short direction is the Y-axis direction (second direction), and the direction orthogonal to the X-axis and Y-axis. (A direction perpendicular to the surface of the substrate 101) is defined as the Z-axis direction (third direction) and will be described.

  In addition, the first LED unit 110, the second LED unit 120, and the third LED unit 130 (hereinafter, collectively referred to as “LED unit” in some cases) of the present embodiment have a wavelength of ultraviolet light emitted from each LED unit. Although the distance between a pair of reflecting mirrors (details will be described later) of each LED unit is different, other configurations are common, and therefore, the configuration of the first LED unit 110 will be mainly described below.

  The first LED unit 110 includes a light source unit 112 disposed on a substrate 101 extending in the X-axis direction, and a pair of reflection mirrors 114a and 114b disposed so as to sandwich the light source unit 112 from the Y-axis direction and extending long in the X-axis direction. And.

  As shown in FIGS. 1 and 3, the light source unit 112 of the first LED unit 110 of the present embodiment has a square light emitting surface 113a at the center, and is 6.8 mm (length in the X-axis direction) × 6.8 mm. It is composed of a plurality of rectangular LED elements (light emitting elements) 113 having a length in the Y-axis direction. The LED elements 113 of the present embodiment are arranged on the substrate 101 in a two-dimensional (Y-axis direction) × 85 (X-axis direction) two-dimensional square lattice shape in such an orientation that the two sides are parallel to the X-axis direction. And is electrically connected to the substrate 101. The board 101 is an electronic circuit board made of glass epoxy resin, ceramics, etc., and is connected to an LED drive circuit (not shown), and each LED element 113 receives a drive current from the LED drive circuit via the board 101. It comes to be supplied.

  As shown in FIG. 3, the LED element 113 of the present embodiment includes four LED chips 113b arranged in a square lattice pattern therein. When a driving current is supplied to each LED element 113, each LED chip 113b emits light with a light amount corresponding to the driving current, and ultraviolet light with a predetermined light amount is emitted from each LED element 113. In the present embodiment, each LED chip 113b is configured to emit ultraviolet light having a wavelength of 365 nm in response to a drive current supplied from the LED drive circuit. That is, each LED element 113 emits ultraviolet light having a wavelength of 365 nm with a predetermined light amount.

  In addition, the drive current supplied to each LED element 113 is adjusted so that each LED element 113 of this embodiment radiates | emits the ultraviolet light of a substantially uniform light quantity, The line radiate | emitted from the 1st LED unit 110 is adjusted. The ultraviolet light has a substantially uniform light amount distribution in the X-axis direction. As shown in FIG. 3, in the present embodiment, the pitch PH in the X-axis direction and the pitch PV in the Y-axis direction of each LED module 110 are both set to about 8 mm.

The pair of reflecting mirrors 114a and 114b are mirrors that are arranged on the XZ plane and guide ultraviolet light emitted from the light source unit 112, with the reflecting surfaces facing inward (that is, the reflecting surfaces face each other). ), so as to sandwich the light source unit 112 from the Y-axis direction and are parallel spaced a ₁ (Fig. 3). As shown in FIG. 2, when viewed from the X-axis direction, the proximal end sides of the pair of reflecting mirrors 114 a and 114 b are disposed close to the light source unit 112, and the distal end side is close to the cover glass 105. The ultraviolet light emitted from the light source unit 112 is guided by the pair of reflection mirrors 114a and 114b, and the cover glass 105 (that is, from the first LED unit 110) is predetermined in the Z-axis direction. A linear ultraviolet light having a divergence angle of and parallel to the X axis is emitted. As described above, since the pair of reflecting mirrors 114a and 114b of the present embodiment are arranged in parallel to the X-axis direction, the spread angle in the Z-axis direction of the ultraviolet light emitted from the cover glass 105 is The ultraviolet light emitted from the LED element 113 is substantially equal to the divergence angle in the Z-axis direction. In the present embodiment, ultraviolet light having an divergence angle of ± about 50 ° is emitted with the Z-axis direction being 0 °. ing. 2 indicates the optical axis of the first LED unit 110 (that is, the optical path center of the ultraviolet light emitted from the first LED unit 110). Further, details will be described later, a pair of reflecting mirrors 114a, spacing _{a 1} of 114b of the 1LED unit 110 includes a pair of reflective mirrors 124a of the 2LED unit 120 is set smaller than the distance _{a 2} of 124b ( FIG. 3).

As described above, the second LED unit 120 has the same configuration as the first LED unit 110, and is disposed at a predetermined distance in the Y-axis direction from the first LED unit 110. The second LED unit 120 includes a light source unit 122 disposed on the substrate 101, and a pair of reflection mirrors 124a and 124b disposed so as to sandwich the light source unit 122 from the Y-axis direction and extending long in the X-axis direction. . Similarly to the light source unit 112, the light source unit 122 includes two rows (Y-axis direction) × 85 LED elements 123 (X-axis direction), but each LED element 123 (that is, the light source unit 122) The light source unit 112 is different in that it is configured to emit ultraviolet light having a wavelength of 405 nm. That is, ultraviolet light having a wavelength of 405 nm emitted from the light source unit 122 is guided by the pair of reflection mirrors 124a and 124b, and from the cover glass 105 (that is, from the second LED unit 120) is ± about 50 in the Z-axis direction. A linear ultraviolet light having a divergence angle of ° and parallel to the X axis is emitted. 2 represents the optical axis of the second LED unit 120 (that is, the optical path center of the ultraviolet light emitted from the second LED unit 120). Further, details will be described later, a pair of reflecting mirrors 124a of the 2LED unit 120, distance _{a 2} of 124b, a pair of reflecting mirrors 114a of the 1LED unit 110, a pair of 114b intervals _{a 1,} and the 3LED unit 130 reflecting mirror 134a of is set larger than the distance _{a 3} of 134b (FIG. 3). In general, ultraviolet light refers to light having a wavelength of 360 to 400 nm, but in this specification, light having a wavelength of 405 nm is also included in the ultraviolet light.

The third LED unit 130 has the same configuration as the first LED unit 110 and the second LED unit 120, and is arranged at a predetermined distance from the second LED unit 120 in the Y-axis direction. The third LED unit 130 includes a light source unit 132 disposed on the substrate 101, and a pair of reflection mirrors 134a and 134b that are disposed so as to sandwich the light source unit 132 from the Y-axis direction and extend long in the X-axis direction. . Similarly to the light source units 112 and 122, the light source unit 132 includes two rows (Y-axis direction) × 85 (X-axis direction) LED elements 133, but each LED element 133 (that is, the light source unit 132). Is different from the light source units 112 and 122 in that ultraviolet light having a wavelength of 385 nm is emitted from. That is, ultraviolet light having a wavelength of 385 nm emitted from the light source unit 132 is guided by the pair of reflection mirrors 134a and 134b, and from the cover glass 105 (that is, from the third LED unit 130) is ± about 50 in the Z-axis direction. A linear ultraviolet light having a divergence angle of ° and parallel to the X axis is emitted. 2 represents the optical axis of the third LED unit 130 (that is, the optical path center of the ultraviolet light emitted from the third LED unit 130). Further, details will be described later, a pair of reflecting mirrors 134a of the 3LED unit 130, spacing _{a 3} of 134b includes a pair of reflective mirrors 124a of the 2LED unit 120, narrower than the distance _{a 2} of 124b, the 1LED unit 110 a pair of reflecting mirrors 114a of being set to 114b become substantially equal to the distance _{a 1} (FIG. 3).

  Thus, the 1st LED unit 110 of this embodiment, the 2nd LED unit 120, and the 3rd LED unit 130 are arrange | positioned at equal intervals along the Y-axis direction, and each parallel ultraviolet light of a different wavelength along the Z-axis direction. It is comprised so that it may radiate | emit to. Accordingly, ultraviolet light having different wavelengths is irradiated on the sheet-shaped irradiation object that moves in close contact with the outer peripheral surface of the drum disposed on the optical path of the first LED unit 110, the second LED unit 120, and the third LED unit 130. Irradiated in order. For this reason, the ultraviolet curable resin applied to the surface of the irradiation object is reliably cured from the surface to the inside.

  In addition, the emission surfaces of the first LED unit 110, the second LED unit 120, and the third LED unit 130 of the present embodiment are arranged flat along the XY plane (that is, the cover glass 105). For this reason, it can respond to the various drums from which an outer diameter differs, and the work space at the time of exchanging a drum is fully ensured.

  However, as in the present embodiment, when the first LED unit 110, the second LED unit 120, and the third LED unit 130 are arranged flat along the Y-axis direction, the distance from each LED unit to the irradiation target is not constant. Therefore, even if the intensity of ultraviolet light emitted from each LED unit is made uniform, ultraviolet light having different peak intensity for each wavelength is incident on the irradiation object. Therefore, in this embodiment, such a problem is solved by adjusting the distance between the pair of reflecting mirrors of each LED unit based on the distance between each LED unit and the irradiation object (that is, the drum). ing.

  FIG. 4 is a diagram for explaining such a problem, and the left side surface of the light irradiation device 100 when a pair of reflecting mirrors of the first LED unit 110, the second LED unit 120, and the third LED unit 130 are set at the same interval. FIG. In FIG. 4, the substrate 101 and the irradiation object P1 are omitted for convenience of explanation. In FIG. 4, the region of the outer peripheral surface of the large-diameter drum D1 irradiated by the first LED unit 110 is a region E1 (part indicated by a thick solid line), and the outer peripheral surface of the large-diameter drum D1 irradiated by the second LED unit 120. This region is schematically shown as a region E2 (a portion indicated by a thick broken line), and a region on the outer peripheral surface of the large-diameter drum D1 irradiated by the third LED unit 130 is indicated as a region E3 (a portion indicated by a thick solid line).

  In FIG. 4, the first LED unit 110, the second LED unit 120, and the third LED unit 130 are arranged at an interval of 32 mm in the Y-axis direction. The distance between the pair of reflecting mirrors 114a and 114b, 124a and 124b, and 134a and 134b is set to 23 mm. Further, the diameter of the large-diameter drum D1 is φ400 mm, and the optical axis AX2 of the second LED unit 120 is arranged so as to substantially coincide with the normal line of the outer peripheral surface of the large-diameter drum D1. Further, the distance from the exit surface of the optical axis AX2 of the second LED unit 120 (that is, the front end surface of the cover glass 105) to the outer peripheral surface of the large-diameter drum D1 (hereinafter, the cover glass 105 of each optical axis AX1, AX2, AX3). The distance from the front end surface to the outer peripheral surface of the large-diameter drum D1 is referred to as “working distance WD”) is set to 5.0 mm, and the working distance WD of the first LED unit 110 and the third LED unit 130 is 7. It is 6 mm.

  As shown by the dotted arrows in FIG. 4, the first LED unit 110, the second LED unit 120, and the third LED unit 130 each emit ultraviolet light having a divergence angle of about ± 50 ° in the Z-axis direction of the large-diameter drum D1. When the light is emitted toward the outer peripheral surface, the first LED unit 110 irradiates the outer peripheral surface region E1 of the large-diameter drum D1, the second LED unit 120 irradiates the outer peripheral surface region E2 of the large-diameter drum D1, and the third LED unit 130. The region E3 on the outer peripheral surface of the large-diameter drum D1 is irradiated by the above, but as described above, since the working distance WD of the second LED unit 120 is the shortest, the circumferential length of the region E2 is the region E1 and the region E3. It becomes shorter than the length in the circumferential direction. Accordingly, when ultraviolet light having the same intensity is emitted from the first LED unit 110, the second LED unit 120, and the third LED unit 130, the intensity of the ultraviolet light per unit area is highest in the region E2, and the peak intensity is also in the region. Highest at E2. That is, the peak intensity of the ultraviolet light with a wavelength of 405 nm emitted from the second LED unit 120 is the peak intensity of the ultraviolet light with a wavelength of 365 nm emitted from the first LED unit 110 and the ultraviolet light with a wavelength of 385 nm emitted from the third LED unit 130. It becomes higher than the peak intensity of light.

FIG. 5 shows the result of obtaining the intensity distribution of ultraviolet light on the large-diameter drum D1 of FIG. 4 by simulation. FIG. 5A shows the intensity distribution in the X-axis direction of ultraviolet light of each wavelength, and the horizontal axis indicates the position in the X-axis direction on the large-diameter drum D1 (the center position of the large-diameter drum D1 having a length of 600 mm). The position when 0 mm is shown), and the vertical axis shows the intensity of ultraviolet light (mW / cm ² ). FIG. 5B shows the strength distribution in the circumferential direction of the large-diameter drum D1, and the horizontal axis indicates the circumferential position of the outer peripheral surface of the large-diameter drum D1 (the optical axis AX2 of the second LED unit 120 is the large-diameter drum). The position where the position intersecting the outer peripheral surface of D1 is 0 mm) is shown, and the vertical axis is the intensity of ultraviolet light (mW / cm ² ). As shown in FIGS. 5A and 5B, the peak intensity of the ultraviolet light having a wavelength of 405 nm emitted from the second LED unit 120 is the peak intensity of the ultraviolet light having a wavelength of 365 nm emitted from the first LED unit 110, and It can be seen that the peak intensity of the ultraviolet light having a wavelength of 385 nm emitted from the third LED unit 130 is higher.

As described above, when ultraviolet light having a different peak intensity for each wavelength is irradiated onto the drum and incident on the ultraviolet curable resin on the surface of the irradiation object (not shown in FIG. 4) arranged in close contact with the drum, Curing is affected by ultraviolet light having a low peak intensity, and the fine structure pattern is not accurately transferred, resulting in a problem that transfer quality and product reliability are significantly reduced. It is also possible to improve the transfer quality by slowing the transfer speed and increasing the integrated light amount in accordance with the ultraviolet light having a low peak intensity. However, this method has a problem that the production efficiency is remarkably lowered. Occur. Therefore, in this embodiment, in order to solve such a problem, the distance between the pair of reflecting mirrors of each LED unit is adjusted based on the distance between each LED unit and the irradiation object (that is, the drum). doing. Specifically, the distance a ₁ between the pair of reflecting mirrors 114a and 114b is set so that the intensity of the ultraviolet light per unit area of the region E1 and the region E3 is substantially equal to the intensity of the ultraviolet light per unit area of the region E2. When a pair of reflection mirrors 134a, narrowing a distance a ₃ of 134b, circumferential length of the region E1 and area E3 has been adjusted so that substantially the circumferential length of the region E2 is equal.

Here, considering the conditions for the circumferential lengths of the region E1 and the region E3 to be equal to the circumferential length of the region E2, first, all of the ultraviolet light emitted from the light source unit of each LED unit is a pair. The distance between each pair of reflecting mirrors of the first LED unit 110, the second LED unit 120, and the third LED unit 130 is a ₁ , a ₂ , and a ₃ , respectively. When the size in the Y direction (that is, the distance from the upper end of the first row of LED elements to the lower end of the second row of LED elements) is c, the following conditional expression (7) is derived.

a ₁ , a ₂ , a ₃ > c (7)

Moreover, since the ultraviolet light of the same divergence angle is emitted in parallel with the Z-axis direction from each LED unit, the circumferential length of each region E1 to E3 is proportional to the working distance WD of each LED unit, and a proportional to spacing between the pair of reflecting mirrors _(i.e., a 1 ~a _3). Therefore, when the working distances WD of the first LED unit 110, the second LED unit 120, and the third LED unit 130 are b ₁ , b ₂ , and b ₃ , the following conditional expression (8) is derived.

a ₁ × b ₁ = a ₂ × b ₂ = a ₃ × b ₃ = k (k is a predetermined constant) (8)

Further, since all ultraviolet light emitted from each LED unit needs to enter the drum, the distance between the reflection mirrors located at both ends in the Y-axis direction (that is, the reflection mirror 114a of the first LED unit 110 and the third LED). If the distance between the unit 130 and the reflecting mirror 134b) is d and the diameter of the drum is e, the following conditional expression (9) is derived.

d <e (9)

  That is, when the conditional expressions (7), (8), and (9) are satisfied, the peak intensity of ultraviolet light having a wavelength of 365 nm emitted from the first LED unit 110 and ultraviolet light having a wavelength of 385 nm emitted from the third LED unit 130 are satisfied. Is approximately equal to the peak intensity of ultraviolet light having a wavelength of 405 nm emitted from the second LED unit 120.

FIG. 6 illustrates a case where the distance a ₁ between the pair of reflection mirrors 114 a and 114 b of the _first LED unit 110 and the distance a ₃ between the pair of reflection mirrors 134 a and 134 b of the _third LED unit 130 are adjusted in the configuration of FIG. It is a left side view of the light irradiation apparatus 100, a pair of reflecting mirrors 114a of the 1LED unit 110, a pair of reflecting mirrors 134a of 114b intervals _{a 1,} and the 3LED unit 130, the spacing _{a 3} of 134b, the conditional expression Based on (7), (8) and (9), it is different from the configuration of FIG. 4 in that it is set to 15 mm. That is, in the configuration of FIG. 6, the intensity of the ultraviolet light per unit area of the region E1 and the region E3 is substantially equal to the intensity of the ultraviolet light per unit area of the region E2 (that is, the region E1 and the region E3). the length in the circumferential direction, to be equal circumferential length substantially areas E2), a pair of reflecting mirrors 114a, spacing _{a 1} and a pair of reflecting mirrors 134a of 114b, spacing _{a 3} of 134b is adjusted Yes.

FIG. 7 shows the result of the simulation of the intensity distribution of ultraviolet light on the large-diameter drum D1 in FIG. FIG. 7A shows the intensity distribution in the X-axis direction of ultraviolet light of each wavelength, and the horizontal axis indicates the position in the X-axis direction on the large-diameter drum D1 (the center position of the large-diameter drum D1 having a length of 600 mm). The position when 0 mm is shown), and the vertical axis shows the intensity of ultraviolet light (mW / cm ² ). FIG. 7B shows the strength distribution in the circumferential direction of the large-diameter drum D1, and the horizontal axis indicates the circumferential position of the outer peripheral surface of the large-diameter drum D1 (the optical axis AX2 of the second LED unit 120 is the large-diameter drum). The position where the position intersecting the outer peripheral surface of D1 is 0 mm) is shown, and the vertical axis is the intensity of ultraviolet light (mW / cm ² ). As shown in FIGS. 7A and 7B, the peak intensity of ultraviolet light having a wavelength of 365 nm emitted from the first LED unit 110 of the present embodiment and the ultraviolet light having a wavelength of 385 nm emitted from the third LED unit 130 are shown. It can be seen that the peak intensity is substantially equal to the peak intensity of ultraviolet light having a wavelength of 405 nm emitted from the second LED unit 120.

Thus, in the light irradiation apparatus 100 of this embodiment, the 1st LED unit 110, the 2nd LED unit 120, and the 3rd LED unit 130 are arrange | positioned flat along a Y-axis direction, and a pair of reflection of the 1st LED unit 110 is carried out. By adjusting the distance a ₁ between the mirrors 114 a and 114 b and the distance a ₃ between the pair of reflecting mirrors 134 a and 134 b of the _third LED unit 130, the peak intensity of the ultraviolet light emitted from each LED unit is adjusted on the irradiation object. It is comprised so that it may become substantially equal. Therefore, if the light irradiation apparatus 100 of this embodiment is applied to a pattern forming apparatus, a fine structure pattern can be accurately transferred without reducing production efficiency.

  The above is the description of the present embodiment, but the present invention is not limited to the above configuration, and various modifications can be made within the scope of the technical idea of the present invention.

  In the present embodiment, the light source unit 112 of the first LED unit 110, the light source unit 122 of the second LED unit 120, and the light source unit 132 of the third LED unit 130 are each two rows (Y-axis direction) × 85 (X-axis direction). The LED elements 113, 123, and 133 are provided, but the present invention is not limited to such a configuration, and n (n is an integer of 2 or more), Y at predetermined intervals along the X-axis direction. Any configuration may be used as long as it is arranged in m columns (m is an integer of 1 or more) at predetermined intervals along the direction.

In the present embodiment, it is configured to irradiate ultraviolet light of three different wavelengths, but is not limited to such a configuration, and the present invention has N types (N is an integer of 2 or more) of different wavelengths. It is possible to apply to the light irradiation apparatus 100 which irradiates ultraviolet light. In the present embodiment, one first LED unit 110 emits ultraviolet light having a wavelength of 365 nm, one second LED unit 120 emits ultraviolet light having a wavelength of 405 nm, and one third LED unit 130 Although the configuration is such that ultraviolet light having a wavelength of 385 nm is emitted, the present invention is not limited to such a configuration, and a plurality of LED units that emit ultraviolet light of each wavelength may be configured. That is, the light irradiation apparatus 100 of the present embodiment includes N × M (M is an integer of 1 or more) LED units that emit light of N types (N is an integer of 2 or more) of different wavelengths. be able to. Further, in this case, N × M LED units are arranged along the Y-axis direction, and the same effects as in the present embodiment are produced as long as the conditional expressions (7), (8), and (9) are satisfied. It is not necessary to arrange them at regular intervals. That is, the conditional expressions (7), (8), and (9) can be generalized as the following conditional expressions (10), (11), and (12).

a _i > c (10)
a _i × b _i = k (k is a predetermined constant) (11)
d <e (12)

Here, a _i represents the optical unit having the longest working distance WD among the N × M optical units (that is, one of the optical units located at both ends in the Y-axis direction) as the first optical unit. When the first to N × M-th optical units are determined in order along the Y-axis direction, a pair of i-th (i is an integer of 1 to N × M) LED units This is the distance between the reflecting mirrors. Further, b _i is the working distance WD of the i-th LED unit (i.e., distance between the exit surface of the optical axes of the LED unit to the outer peripheral surface of the drum) is, c is is the size of the Y-axis direction of the light source unit . D is the distance between the reflecting mirrors located at both ends in the Y-axis direction, and e is the diameter of the drum.

  Further, in the present embodiment, the first LED unit 110, the second LED unit 120, and the third LED unit 130 are arranged in order along the Y-axis direction, and the ultraviolet light having a wavelength of 365 nm, the wavelength as the irradiation object moves The ultraviolet light with a wavelength of 405 nm and the ultraviolet light with a wavelength of 385 nm are sequentially received. However, the ultraviolet curable resin applied on the irradiation target may be reliably cured, and the order is not limited. In addition, in the pattern forming apparatus in which the light irradiation apparatus 100 of this embodiment is mounted, it is possible to form a highly accurate pattern by curing the interior of the ultraviolet curable resin after the surface of the ultraviolet curable resin is cured. It is desirable to arrange each LED unit so that the object receives light of a short wavelength to a long wavelength in order, and when using the N × M LED units described above, for each wavelength (that is, N It is desirable to arrange them in groups.

  Moreover, although the LED element 113 of the present embodiment includes the four LED chips 113a arranged in a square lattice pattern, the present invention is not limited to this configuration, and includes at least one LED chip. It only has to be.

(Second Embodiment)
FIG. 8 is a left side view illustrating the configuration of the light irradiation apparatus 200 according to the second embodiment of the present invention. The light irradiation apparatus 200 of this embodiment is an apparatus that irradiates the small-diameter drum D2 with ultraviolet light, and includes a pair of extension mirrors 210 and 230 that extend from the cover glass 105 toward the outer peripheral surface of the small-diameter drum D2. It differs from the light irradiation apparatus 100 of 1st Embodiment by the point by which the space | interval of a pair of reflective mirror 124a, 124b of 2LED unit 120 is set to 25 mm. In this embodiment, the diameter of the small-diameter drum D2 is φ100 mm, the working distance WD of the second LED unit 120 is 5.0 mm, and the working distance WD of the first LED unit 110 and the third LED unit 130 is 16.6 mm. In FIG. 8, as in FIG. 6, the substrate 101 and the irradiation object P1 are omitted for convenience of explanation. Also in FIG. 8, as in FIG. 4, the outer peripheral surface area of the small-diameter drum D <b> 2 irradiated by the first LED unit 110 is an area E <b> 1 (part indicated by a thick solid line), and the small-diameter drum D <b> 2 irradiated by the second LED unit 120. The region of the outer peripheral surface is schematically shown as region E2 (part indicated by a thick broken line), and the region of the outer peripheral surface of the small-diameter drum D2 irradiated by the third LED unit 130 is indicated as region E3 (part indicated by a thick solid line).

  Since the ultraviolet light emitted from the first LED unit 110, the second LED unit 120, and the third LED unit 130 has a predetermined divergence angle, the diameter of the small-diameter drum D2 is small as in this embodiment, and the second LED unit When the difference between the working distance WD2 of 120 and the working distances WD1 and WD3 of the first LED unit 110 and the third LED unit 130 increases, a part of the ultraviolet light emitted from the first LED unit 110 and the third LED unit 130 is a small diameter drum. It will be irradiated outside D2. Therefore, in the present embodiment, a pair of the reflection mirror 114a of the first LED unit 110 and the reflection mirror 134b of the third LED unit 130 located on the outermost side in the Y-axis direction are extended with the cover glass 105 interposed therebetween. Extension mirrors 210 and 230 are provided.

  The extension mirror 210 is a rectangular reflection mirror that extends long in the X-axis direction, and is disposed on the same plane as the reflection mirror 114a with the reflection surface facing the optical axis AX1 side of the first LED unit 110. When viewed from the X-axis direction, the base end portion of the extension mirror 210 is disposed close to the cover glass 105, and the distal end portion is disposed near the outer peripheral surface of the small-diameter drum D2. Therefore, as described above, the ultraviolet light emitted from the first LED unit 110 spreads at a predetermined spread angle along the Z-axis direction, but tends to spread toward the reflection mirror 114a (that is, the upper side in FIG. 8). The ultraviolet light is reflected on the outer peripheral surface of the small-diameter drum D2 by the extension mirror 210 (FIG. 8: R1), and irradiates the region E1. Thus, the direct light from the first LED unit 110 and the reflected light from the extension mirror 210 are incident on the region E1. Here, since the ultraviolet light emitted from the first LED unit 110 is mixed by the pair of reflection mirrors 114 a and 114 b and has a uniform intensity, the direct light from the first LED unit 110 and the extension mirror 210 are mixed. The reflected light has the same intensity. Therefore, when the direct light from the first LED unit 110 and the reflected light from the extension mirror 210 are incident on the region E1, the peak intensity is approximately doubled. That is, the peak intensity of the ultraviolet light incident on the region E1 of the present embodiment is about twice the peak intensity of the ultraviolet light incident on the region E1 of the first embodiment.

  Similarly to the reflection mirror 210, the extension mirror 230 is a rectangular reflection mirror that extends long in the X-axis direction, and is disposed on the same plane as the reflection mirror 134b with the reflection surface facing the optical axis AX3 side of the third LED unit 130. ing. When viewed from the X-axis direction, the base end portion of the extension mirror 230 is disposed close to the cover glass 105, and the distal end portion is disposed near the outer peripheral surface of the small-diameter drum D2. Therefore, as described above, the ultraviolet light emitted from the third LED unit 130 spreads at a predetermined spread angle along the Z-axis direction, but tends to spread toward the reflection mirror 134b (that is, the lower side in FIG. 8). The ultraviolet light to be reflected is reflected on the outer peripheral surface of the small-diameter drum D2 by the extension mirror 230 (FIG. 8: R3), and irradiates the region E3. Thus, the direct light from the third LED unit 130 and the reflected light from the extension mirror 230 are incident on the region E3. Therefore, like the region E1 described above, the peak intensity of the ultraviolet light incident on the region E3 of the present embodiment is approximately twice the peak intensity of the ultraviolet light incident on the region E3 of the first embodiment.

As described above, the peak intensity of the ultraviolet light emitted from the first LED unit 110 and the third LED unit 130 of the present embodiment on the outer peripheral surface of the small-diameter drum D2 is about 2 as compared with that of the first embodiment. Doubled. For this reason, in this embodiment, said conditional expression (7) and (8) is changed into the following conditional expressions (13) and (14), and the space | interval of a pair of reflective mirror 124a, 124b of the 2nd LED unit 120 is obtained. by setting based a ₂ to conditional expression (13) and (14), the peak intensity of the ultraviolet light emitted from the LED unit is a substantially equal.

a ₁ , a ₂ , a ₃ > c (13)
_{a 1 × b 1/2 =} a 2 × b 2 = a 3 × b 3/2 = k (k is a predetermined constant) (14)

In addition, according to the light irradiation apparatus 200 of the present embodiment, the pair of extension mirrors 210 and 230 causes the ultraviolet light originally irradiated to the outside of the small diameter drum D2 to be folded back to the small diameter drum D2 side. The drum diameter can be reduced to a distance of 210 and 230. That is, when the distance between the pair of extension mirrors 210 and 230 (that is, the distance between the reflection mirror 114a of the first LED unit 110 and the reflection mirror 134b of the third LED unit 130) is d and the diameter of the drum is e, Conditional expression (15) is derived.

d ≦ e (15)

  As described above, in this embodiment, when the conditional expressions (13), (14), and (15) are satisfied, the peak intensity of ultraviolet light having a wavelength of 365 nm emitted from the first LED unit 110 is emitted from the second LED unit 120. The peak intensity of ultraviolet light having a wavelength of 405 nm and the peak intensity of ultraviolet light having a wavelength of 385 nm emitted from the third LED unit 130 are substantially equal.

FIG. 9 shows the result of obtaining the intensity distribution of the ultraviolet light on the small diameter drum D2 of FIG. 8 by simulation. FIG. 9A shows the intensity distribution in the X-axis direction of ultraviolet light of each wavelength, and the horizontal axis indicates the position in the X-axis direction on the small-diameter drum D2 (the center position of the small-diameter drum D2 having a length of 600 mm is 0 mm). The vertical axis represents the intensity of ultraviolet light (mW / cm ² ). FIG. 9B shows the intensity distribution in the circumferential direction of the small-diameter drum D2, and the horizontal axis indicates the circumferential position of the outer circumferential surface of the small-diameter drum D2 (the optical axis AX2 of the second LED unit 120 is the outer circumference of the small-diameter drum D2). The position where the position intersecting the surface is 0 mm) is shown, and the vertical axis shows the intensity of ultraviolet light (mW / cm ² ). As shown in FIGS. 9A and 9B, as in the first embodiment, the peak intensity of ultraviolet light having a wavelength of 365 nm emitted from the first LED unit 110 of this embodiment is emitted from the second LED unit 120. It can be seen that the peak intensity of ultraviolet light having a wavelength of 405 nm and the peak intensity of ultraviolet light having a wavelength of 385 nm emitted from the third LED unit 130 are substantially equal.

  Thus, also in the light irradiation apparatus 200 of this embodiment, it is comprised so that the peak intensity of the ultraviolet light radiate | emitted from each LED unit may become substantially equal on an irradiation target object similarly to 1st Embodiment. . Therefore, if the light irradiation apparatus 200 of this embodiment is applied to a pattern forming apparatus, a fine structure pattern can be accurately transferred without reducing production efficiency.

  In addition, the light irradiation apparatus 200 of this embodiment is provided with a pair of extension mirrors 210 and 230, and the light irradiation apparatus 100 of the first embodiment is different in that the distance between the pair of reflection mirrors 124a and 124b of the second LED unit 120 is different. And different. Therefore, if the pair of extension mirrors 210 and 230 are configured to be detachable and the pair of reflection mirrors 124a and 124b of the second LED unit 120 are configured to be adjustable, the present embodiment can be used according to the outer diameter of the drum to be used. It is also possible to switch between the light irradiation apparatus 200 and the light irradiation apparatus 100 of the first embodiment.

In addition, the light irradiation apparatus 200 of this embodiment is also N × M pieces (M is the light emission apparatus 100) that emits N types (N is an integer of 2 or more) of different wavelengths, like the light irradiation apparatus 100 of the first embodiment. It can be set as the structure provided with LED unit of 1 or more integers. Therefore, generalizing the conditional expressions (13), (14), and (15) according to the first embodiment is as follows.

a ₁ , a _{(N × M)} , a _i > c (16)
_{a 1 × b 1/2 =} a (N × M) × b (N × M) / 2 = a i × b i = k (k is a predetermined constant)
... (17)
d ≦ e (18)

Here, a ₁ is an N × M optical unit having the longest working distance WD as the first optical unit, and the first to N × M in order along the Y-axis direction. The distance between the pair of reflecting mirrors of the first LED unit when the first optical unit is determined. B ₁ is a working distance WD of the first LED unit. Further, a _{(N × M)} is a distance between the pair of reflecting mirrors of the N × M-th LED unit, and b _{(N × M)} is a working distance WD of the N × M-th LED unit. is there. A _i is the distance between the pair of reflecting mirrors of the i-th LED unit (i is an integer not less than 2 (N × M−1)), and b _i is the i-th LED unit. Working distance WD. D is the distance between the reflecting mirrors located at both ends in the Y-axis direction, and e is the diameter of the drum.

(Third embodiment)
FIG. 10 is a diagram illustrating the configuration of the first LED unit 110A, the second LED unit 120A, and the third LED unit 130A provided in the light irradiation apparatus 300 according to the third embodiment of the present invention. In the first LED unit 110A, the second LED unit 120A, and the third LED unit 130A of the present embodiment, the LED elements 113, 123, and 133 arranged on each LED unit are staggered (that is, 85 in the first row). Are different from the light irradiating apparatus 100 of the first embodiment in that the LED elements are alternately offset with respect to the 85 LED elements in the second row by a distance of ½ of the distance PH. .

  When the LED elements 113, 123, 133 are arranged in this way, two lines of line-shaped ultraviolet light emitted from the first LED unit 110A, the second LED unit 120A, and the third LED unit 130A are converted into the LED elements 113, 123, The offset is relatively offset in the X-axis direction by a distance ½ of the interval PH of 133. Therefore, since each line-shaped ultraviolet light cancels out the portions where the light quantity distribution is low, a substantially uniform light quantity distribution in the X-axis direction can be obtained on the irradiation object.

(Fourth embodiment)
FIG. 11 is a diagram illustrating the configuration of the first LED unit 110B, the second LED unit 120B, and the third LED unit 130B provided in the light irradiation apparatus 400 according to the fourth embodiment of the present invention. In the first LED unit 110B, the second LED unit 120B, and the third LED unit 130B of this embodiment, the LED elements 113, 123, and 133 arranged on each LED unit have one diagonal line parallel to the X-axis direction. It differs from the light irradiation apparatus 100 of 1st Embodiment by the point arrange | positioned so that it may become.

  When the LED elements 113, 123, 133 are arranged in this manner, the ultraviolet light emitted from each LED element and the ultraviolet light emitted from the LED element adjacent to each LED element are mutually over in the X-axis direction and the Y-axis direction. Since it wraps, a more uniform light quantity distribution is obtained on the irradiation object.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

100, 200, 300, 400 Light irradiation device 101 Substrate 105 Cover glass 110, 110A, 110B First LED unit 112, 122, 132 Light source 113, 123, 133 LED element 113a Light emitting surface 113b LED chips 114a, 114b, 124a, 124b , 134a, 134b Reflective mirrors 120, 120A, 120B Second LED unit 130, 130A, 130B Third LED unit

Claims (11)

A light irradiation device for irradiating light onto a sheet-like irradiation object that moves in close contact with a part of the outer peripheral surface of a cylindrical drum,
N (n is an integer of 2 or more) at a first predetermined interval along a first direction parallel to the central axis of the drum on the substrate, and along a second direction orthogonal to the first direction. A light source unit composed of a plurality of light emitting elements arranged in m rows (m is an integer of 1 or more) at a predetermined interval of 2 and arranged with the direction of the optical axis aligned in a third direction orthogonal to the substrate surface; A pair of reflecting mirrors extending in the first direction and the third direction so as to sandwich the optical axes of the plurality of light emitting elements from the second direction, and arranged so that the reflecting surfaces face each other, A plurality of optical units that guide light from the light source unit with the pair of reflection mirrors and emit light with a predetermined divergence angle and light amount to a part of the outer peripheral surface of the drum,
The plurality of optical units includes N × M (M is an integer of 1 or more) optical units that emit light of N types (N is an integer of 2 or more) of different wavelengths,
Each exit surface of the N × M optical units is disposed on a predetermined reference plane defined by the first direction and the second direction,
The distance between the pair of reflecting mirrors of each optical unit is set based on the distance from the reference plane of the optical axis to the outer peripheral surface of the drum. Among the N × M optical units, the optical unit having the longest distance from the reference plane of the optical axis to the outer peripheral surface of the drum is set as the first optical unit in order along the second direction. When the first to N × M-th optical units are determined, the distance between the pair of reflecting mirrors of the i-th (i is an integer of 1 to N × M) optical unit is defined as a _i . The distance from the reference plane of the optical axis to the outer peripheral surface of the drum is b _i , the size of the light source unit in the second direction is c, and the distance between reflection mirrors located at both ends in the second direction is d. The light irradiation apparatus according to claim 1, wherein the following expressions (1), (2), and (3) are satisfied when the diameter of the drum is e.

a _i > c (1)
a _i × b _i = k (k is a predetermined constant) (2)
d <e (3)
Among the N × M optical units, the optical unit having the longest distance from the reference plane of the optical axis to the outer peripheral surface of the drum is set as the first optical unit in order along the second direction. When the first to (N × M) th optical units are defined, they extend substantially in parallel to the vicinity of the outer peripheral surface of the drum from the front ends of the reflecting mirrors located at both ends in the second direction, and the first And a pair of extension mirrors that respectively reflect the light emitted from the N × Mth optical unit,
The distance between the pair of reflecting mirrors of the first-th optical unit and a _1, a distance from the reference plane of the optical axis of the first-th optical unit to the outer circumferential surface of the drum and b _1, The distance between the pair of reflecting mirrors of the N × Mth optical unit is a _{(N × M),} and the outer peripheral surface of the drum from the reference plane of the optical axis of the N × Mth optical unit. B _{(N × M),} and the distance between the pair of reflecting mirrors of the i-th optical unit (i is an integer not less than 2 (N × M−1)) is a _i , The distance from the reference plane of the optical axis of the i-th optical unit to the outer peripheral surface of the drum is b _i , the size of the light source unit in the second direction is c, and the distance is located at both ends in the second direction. The distance between the reflection mirrors is d, and the diameter of the drum is e. The light irradiation apparatus according to claim 1, wherein the following expressions (4), (5), and (6) are sometimes satisfied.

a ₁ , a _{(N × M)} , a _i > c (4)
_{a 1 × b 1/2 =} a (N × M) × b (N × M) / 2 = a i × b i = k (k is a predetermined constant)
... (5)
d ≦ e (6)
  4. The light irradiation according to claim 1, wherein the emission surfaces of the N × M optical units are arranged at equal intervals along the second direction. 5. apparatus.   The N × M optical units are arranged in groups for each wavelength so that the irradiation object sequentially receives light from a short wavelength to a long wavelength as the irradiation object moves. The light irradiation apparatus according to claim 1, wherein the light irradiation apparatus is a light irradiation apparatus.   The plurality of light emitting elements are LEDs (Light Emitting Diodes) having a substantially square light emitting surface, and are arranged such that two sides of the light emitting surface are parallel to the first direction. The light irradiation apparatus as described in any one of Claims 1-5.   The plurality of light-emitting elements are LEDs having a substantially square light-emitting surface, and are arranged so that one diagonal line of the light-emitting surface is parallel to the first direction. The light irradiation apparatus as described in any one of Claims 5. M is 2 or more,
Among the plurality of light emitting elements, the light emitting elements in the v-th column (v is an integer of 1 to (m−1)) in the second direction are 8. The light irradiation device according to claim 1, wherein the light irradiation device is arranged so as to be shifted in the first direction by a distance of ½ of a predetermined interval of 1.   The said light emitting element has at least 1 or more LED chip, The light irradiation apparatus as described in any one of Claims 1-8 characterized by the above-mentioned.   The light of N different wavelengths is light including a wavelength that acts on an ultraviolet curable resin applied to the surface of the irradiation object. The light irradiation apparatus as described in.   11. The light irradiation apparatus according to claim 1, wherein each of the pair of reflection mirrors has a rectangular shape when viewed from the second direction. .

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