JP6094253B2 - Light source unit and irradiation device - Google Patents

Description

  The present invention relates to a light source unit including a plurality of light emitting elements in a light source and an irradiation apparatus.

  2. Description of the Related Art Conventionally, for example, an illumination device including a diffuse reflection surface that diffuses and reflects light from a light source in which a plurality of light emitting elements such as LEDs are arranged (see, for example, Patent Document 1). According to this illuminating device, even when each LED is spaced apart and the illuminance is high at a position corresponding to each LED, the light of each LED is diffused by the diffuse reflection surface, so that the illuminance unevenness is suppressed. The (For example, refer to Patent Document 1).

JP 2007-101309 A

However, when it is attempted to sufficiently diffuse the light of each of the plurality of spaced LEDs to suppress uneven illuminance, there is a problem that the outline of the irradiation field is blurred depending on the intensity of the diffusion.
That is, when a plurality of LEDs are arranged apart and irradiated with light extending in the direction of the separation, illuminance unevenness in the direction in which the light extends is eliminated, but in the light width direction orthogonal to the extending direction. The outline is blurred.

  The present invention has been made to solve the above-described problems, and provides a light source unit and an irradiation apparatus that can sufficiently suppress blurring of an outline while suppressing unevenness in illuminance of light extending in the arrangement direction of light emitting elements. Objective.

In order to achieve the above object, the light source unit of the present invention controls a plurality of light emitting elements arranged and the light of each of the light emitting elements, and extends in the direction of the light emitting element arrangement, thereby suppressing illuminance unevenness. An optical system for making the light, and the optical system includes a reflecting surface that collimates the light of the light emitting element, a plurality of parallel lights from the reflecting surface, and a direct light of the light emitting element . Each of the elliptical lenses has an incident surface having a concave surface, and a major axis direction is directed to a width direction of the extending light, and a minor axis direction is directed to the extending direction of the light , The parallel light is arranged in a row in the light extending direction, the parallel light is diffused in the short axis direction and emitted, and the curvature in the long axis direction of the incident surface is determined by the parallel light in the irradiation region. It is a curvature that directs the direct light within a width .

Further, in the above light source unit, a pre-Symbol reflecting surface, arranged, characterized in that extended to the end portion of the long axis direction of each of the arranged the elliptical lens.

  In the light source unit, the light source unit may include an attachment body to which the light emitting element is attached, and the end portions of the attachment body may be extended to the end portions in the major axis direction of the elliptic lenses arranged side by side. It is characterized by.

Further, the present invention is the above light source unit, further comprising: an attachment body in which the reflection surface extends to an end portion in the major axis direction of each of the elliptical lenses arranged side by side, and the light emitting element is attached thereto. Each of the elliptical lenses arranged side by side extends to the end in the major axis direction, the attachment body is columnar, and a plurality of the light emitting elements are arranged side by side on the outer peripheral surface of the attachment body, and the reflection A surface surrounds the attachment body and is provided to face the outer peripheral surface, and the attachment body is attached to the reflection surface by fitting.

  Moreover, the irradiation apparatus of the present invention includes any one of the light source units described above.

  According to the light source unit of the present invention, the light incident on the elliptical lens is diffused in the extending direction of the light that is generated by the optical system so as to extend in the direction in which the light emitting elements are arranged. While suppressing unevenness, blurring of the outline in the width direction of light can be sufficiently suppressed.

It is a conceptual diagram of the irradiation apparatus which has a light source unit which concerns on embodiment of this invention. It is a figure which shows an example of the light shaping filter of a light source unit. It is a figure which shows the irradiation field of the emitted light of the optical system of a light source unit with the area | region which each light of LED covers, (A) shows the case where the area | region which the light of adjacent LED covers is overlapped, ( B) shows a case where the area EA covered by the light of the adjacent LED is not overlapped. It is a figure which shows the detailed structure of an irradiation apparatus, (A) shows a top view, (B) shows a bottom view, (C) shows a side view, (D) shows a front view. It is a disassembled perspective view of an irradiation apparatus. It is a perspective view which decomposes | disassembles and shows a part of light source unit. It is VII-VII arrow sectional drawing of (A) of FIG. It is a figure which shows the structure of an optical shaping | molding filter, (A) shows the perspective view which looked at the optical shaping filter from the entrance plane side, (B) shows the BB arrow sectional drawing of (A), C) is a cross-sectional view taken along the line CC of (A). It is a principal part ray diagram of the light which the optical system of a light source unit makes. It is a light ray diagram explaining the extension of the extension direction of the light which passes an elliptic lens, and the width direction. It is a figure which shows the illumination intensity distribution of the light which each optical system of a light source unit and the light source unit of Comparative Examples 1 and 2 shows, (A) shows the illumination intensity distribution of a light source unit, (B) is the light source of the comparative example 1. The illuminance distribution of the unit is shown, and (C) shows the illuminance distribution of the light source unit of Comparative Example 2.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a conceptual diagram of an irradiation apparatus 1 having a light source unit 3 according to an embodiment of the present invention, and FIG. 2 is a diagram showing an example of a light shaping filter 11 of the light source unit 3.

In FIG. 1, an irradiation apparatus 1 is an exposure apparatus that irradiates an irradiation target S with ultraviolet rays (light) in order to create a fine pattern on a silicon wafer (irradiation target). Irradiate light that extends.
The irradiation device 1 includes a light source unit 3 and a case (not shown) that houses the light source unit 3 to be described later.
The light source unit 3 includes a plurality of LEDs 4 that are light emitting elements, a mounting body 5, and an optical system 7.
The plurality of LEDs 4 are provided as light sources of the light source unit 3. The LED 4 is an ultraviolet LED that emits ultraviolet rays. The plurality of LEDs 4 are mounted side by side on the mounting body 5. The arrangement of the plurality of LEDs 4 is appropriately set in a linear shape or an annular shape according to the specifications of the irradiation device 1.
The optical system 7 includes a collimating member (parallel collimating means) 9 and a light shaping filter 11.
The light from each of the plurality of LEDs 4 is incident on the collimating member 9. The collimating member 9 collimates each incident light of the LED 4 and outputs the collimated light to the light shaping filter 11. Techniques for collimating light are known techniques such as those using a lens (not shown) and those using a reflecting mirror (not shown). The collimating member 9 may be configured by appropriately adopting these known techniques, and the configuration of the collimating member 9 is not particularly limited.
Further, since the plurality of LEDs 4 are arranged side by side, the emitted light LF of the collimating member 9 extends in the direction in which the LEDs 4 are arranged and has a width in a direction orthogonal to the predetermined direction.

The outgoing light LF of the collimating member 9 becomes the incident light LP of the light shaping filter 11, and the light shaping filter 11 does not diffuse the incident light LP in the width direction but diffuses it in the direction in which the light extends. It is set as the structure made to go to the object S. The light emitted from the light shaping filter 11, in other words, the light produced by the optical system 7 is directed to the irradiation target S as the emitted light LF of the irradiation device 1.
The irradiation field SA of the emitted light LF extends in the direction in which the LEDs 4 are arranged, and has a predetermined width in the width direction W orthogonal to the extending direction V. For example, when the LEDs 4 are arranged in a straight line, the irradiation field SA of the emitted light LF extends in the linear direction (extension direction) V in which the LEDs 4 are arranged and has a predetermined width in the width direction W orthogonal to the extension direction V. .

Next, the function and effect of the light source unit 3 will be described using a specific example of the light shaping filter 11.
In FIG. 1, the example in which the optical system 7 generates light linearly extending in a predetermined direction has been described, but in the following, the case where the optical system 7 generates annular light will be described.
FIG. 2 is a perspective view showing an example of the light shaping filter 11 of the light source unit 3. FIG. 3 is a view showing the irradiation field SB of the emitted light LF of the optical system 7 of the light source unit 3 together with the area EA covered by each light of the LED 4. 3A shows a case where the area EA covered by the light of the adjacent LED 4 is overlapped, and FIG. 3B shows a case where the area EA covered by the light of the adjacent LED 4 is not overlapped. ing.

As shown in FIG. 2, the optical shaping filter 11 includes an annular lens group 17 configured by arranging a plurality of elliptical lenses 15 in the circumferential direction without gaps. The plurality of elliptical lenses 15 are arranged side by side in the direction (circumferential direction) in which the outgoing light LF extends with the major axis direction in the width direction of the outgoing light LF created by the optical system 7. A plurality of elliptical lenses 15 controls the incident light LP to be emitted light LF, but the extending directions of the incident light LP and the emitted light LF are the same.
Here, although not shown in detail, in the light source unit 3, the plurality of LEDs 4 are annularly arranged at equal intervals. The lights of the plurality of LEDs 4 that have been collimated by the collimating member 9 are incident on the light shaping filter 11 as incident light LP having an annular contour.

The elliptic lens 15 has a characteristic of diffusing the incident light LP in the minor axis direction and emitting it. Since the major axis direction of the elliptic lens 15 is directed to the width direction of the emitted light LF created by the optical system 7, the minor axis direction of the elliptic lens 15 is directed to the direction in which the emitted light LF extends. For this reason, the light shaping filter 11 diffuses light obtained by collimating each light of the LED in the direction in which the emitted light LF of the light shaping filter 11 extends by the elliptic lens 15 and then directs the light to the area EA. Therefore, the illuminance unevenness of the emitted light LF from the light shaping filter 11 is suppressed. Further, the light shaping filter 11 directs the light obtained by collimating each light of the LED 4 to each of the areas EA without diffusing in the width direction of the outgoing light LF. For this reason, the outline in the width direction of the irradiation field SB by the emitted light LF is not blurred.
By changing the arrangement interval of the plurality of LEDs 4, the main area EA covered by the light of each LED 4 in the emitted light LF of the optical system 7 is partially overlapped as shown in FIG. It is also possible to connect them, and as shown in FIG. 3B, they can be arranged without overlapping.
The plurality of LEDs 4 are appropriately arranged within a range that ensures the required illuminance and satisfies the required illuminance unevenness suppression conditions. The condition for suppressing the unevenness in illuminance may use the value of the uniformity as an index, for example, the uniformity in the irradiation field SB is 20% or less.

  The operational effects of the light source unit 3 described with reference to FIGS. 2 and 3 have been described for the case where the optical system 7 produces the emitted light LF having an annular contour. However, as long as the optical system 7 is not limited to the emitted light extending in the circumferential direction but has a predetermined width in the width direction W and the emitted light extending in the predetermined extending direction V, the inside of the irradiation field of the emitted light LF Illuminance unevenness and blurring of contours on both sides in the width direction of the irradiation field are suppressed.

Further, the light source unit 3 of the present embodiment has a cooling structure for cooling the plurality of LEDs 4.
Returning to FIG. 1, the attachment body 5 also functions as a cooling body for cooling the plurality of LEDs 4. A pair of entrance / exit ports 21 and 23 are attached to the outer peripheral surface of the attachment body 5, and a flow path 25 extending from one entrance / exit port 21 to the other entrance / exit port 23 is formed inside the attachment body 5. Yes. For example, a cooling medium such as cooling water is supplied (introduced) from the inlet / outlet port 21 and discharged from the inlet / outlet port 23 through the channel 25. The cooling medium flowing through the flow path 25 takes heat of the plurality of LEDs 4 and is discharged to the outside, whereby the LEDs 4 are cooled.

Next, the detailed structure of the irradiation apparatus 1 will be described.
4A and 4B are diagrams showing a detailed configuration of the irradiation apparatus 1. FIG. 4A shows a plan view, FIG. 4B shows a bottom view, and FIG. 4C shows a side view. 4D shows a front view. FIG. 5 is an exploded perspective view of the irradiation apparatus 1. 6 is an exploded perspective view showing a part of the light source unit 3, and FIG. 7 is a cross-sectional view taken along arrow VII-VII in FIG.
4 and 5, the irradiation device 1 has a configuration in which the light source unit 3 is housed in a case unit 27.
As shown in FIGS. 5 and 6, the light source unit 3 includes a reflecting member 9 </ b> A that is an aspect of a parallel light-generating member, an attachment body 5 to which a plurality of LEDs 4 are attached, and a light shaping filter 11.
The reflection member 9 </ b> A is formed in a columnar shape having a bowl-shaped reflection surface 41 that opens at one end surface. A fitting insertion hole 43 for fitting the attachment body 5 is formed at the bottom of the reflecting surface 41. A step 45 is formed in the fitting hole 43 to reduce the diameter of the hole at the other end relative to the diameter of the remaining part.

The reflecting member 9A is made of a resin other than the reflecting surface 41, and the reflecting surface 41 is formed by evaporating aluminum.
Moreover, the attachment body 5 is attached to the fitting insertion hole 43 by fitting. The attachment body 5 includes a main body portion 47 and a lid portion 49.
As shown in FIGS. 5 and 7, the main body 47 has a columnar shape having a polygonal cross section, and is formed with a concave section 51 having a circular cross section that opens at one end face in the longitudinal direction. The number of corners of the main body 47 formed in a polygon is the same as the number of LEDs 4 attached, and is set to 10 in this embodiment.
The lid 49 has a disk shape and is provided so as to close the recess 51. A female thread is formed on the inner peripheral surface of the recess 51 on the opening end side. Further, a male screw is formed on the outer peripheral surface of the lid portion 49, and the lid portion 49 is screwed into the concave portion 51 and fixed to the main body portion 47. As a result, the flow path 25 for flowing the cooling medium is formed in the mounting body 5 as shown in FIG. 7 as described above, and details thereof will be described later.

Further, a stepped portion 57 is formed in the vicinity of the other end of the main body portion 47, and the outer shape of the main body portion 47 on the other end side is narrowed in a step shape. The mounting body 5 is disposed by inserting the other end side of the main body 47 into the fitting insertion hole 43 of the reflecting member 9 </ b> A, and is accommodated in the bowl-shaped reflecting surface 41. That is, the outer peripheral surface of the attachment body 5 is disposed at a position surrounded by the reflection surface 41. The attachment body 5 is fitted into the reflecting member 9A until the stepped portion 57 of the main body 47 and the stepped portion 45 of the reflecting member come into contact with each other.
A stepped portion 55 is formed in the vicinity of one end of the main body portion 47, and the outer shape on one end side of the main body portion 47 is narrowed in a step shape.
Moreover, the main-body part 47 is comprised so that an external shape may become small gradually from the one end vicinity to the other end vicinity. As a result, ten wall surfaces that are gradually inclined are formed on the outer peripheral surface 52 (the outer peripheral surface of the mounting body 5) of the main body 47. Ten inclined wall surfaces serve as a light source mounting surface 53 facing the reflecting surface 41.

As shown in FIGS. 6 and 7, an annular opening 59 that faces the reflective surface 41 is formed between the opening edge of the reflective surface 41 and one end of the light source mounting surface 53 that is annularly continuous. Is done. Further, the reflection surface 41 is configured by a plurality of concave reflection surfaces 61 arranged continuously in the circumferential direction, and each of the concave reflection surfaces 61 faces the plurality of light source mounting surfaces 53.
The LED 4 is attached to each of the light source attachment surfaces 53 via an LED substrate 63. Accordingly, the LEDs 4 are arranged in the circumferential direction on the outer peripheral surface 52 of the attachment body 5. Each of the concave reflecting surfaces 61 is disposed at a position corresponding to each of the LEDs 4, and collimates the light of the corresponding LED 4 toward the opening 59.
An annular light shaping filter 11 is provided at a position that closes the opening 59 and controls light incident through the opening 59.
Here, as shown in FIG. 7, the light source mounting surface 53 is inclined in a direction facing the side opposite to the opening 59. In addition, the optical axis direction K of the LED 4 is inclined by an angle α with respect to a plane parallel to the opening of the opening 59, and the light of the LED 4 moves away from the opening of the opening 59 toward the front in the emission direction. Head. Thereby, compared with the case where the optical axis direction K of LED4 is parallel to the opening of the opening part 59, it is suppressed that the light of LED4 goes directly to the optical shaping filter 11. FIG. That is, after the main part of the light of the LED 4 is reflected by the reflecting surface 41, it goes to the light shaping filter 11.

FIG. 8 is a diagram showing the configuration of the light shaping filter 11. FIG. 8A shows a perspective view of the light shaping filter 11 viewed from the incident surface 11A side, and FIG. 8B shows the structure of FIG. FIG. 8C is a cross-sectional view taken along the line B-B in FIG. 8A, and FIG. 8C is a cross-sectional view taken along the line C-C in FIG.
As described above, the light shaping filter 11 includes the lens groups 71 and 73 in which a plurality of elliptical lenses 15 having the major axis direction in the width direction of the emitted light LF are arranged in an annular shape without a gap.
In this embodiment, the light shaping filter 11 has two rows of lens groups 71 and 73 arranged substantially concentrically. The two lens groups 71 and 73 are arranged without gaps in the long axis direction with the long axis direction as the column direction. The incident surfaces 11 </ b> A of the lens groups 71 and 73 are configured by the incident surfaces 15 </ b> A of the plurality of elliptical lenses 15. Each incident surface 15A of the elliptical lens 15 has a concave curved surface in each of a cross section orthogonal to the long axis direction and a cross section orthogonal to the short axis direction.
The width of light produced by the optical system 7 changes according to the length of the elliptical lens 15 in the major axis direction and the curvature of the cross section. Further, the rows of the lens groups 71 and 73 may be appropriately set according to the width of the light produced by the optical system 7, regardless of the two rows.
Further, flanges 65 and 67 are extended from the two rows of lens groups 71 and 73 over the entire circumferential direction. The two rows of lens groups 71 and 73 have a cross-sectional shape in which the incident surface 15A side is convex with respect to the flanges 65 and 67.

As shown in FIGS. 5 to 7, the optical shaping filter 11 is arranged so that the incident surface 11 </ b> A side faces the reflecting surface 41, and the lens groups 71 and 73 are fitted into the opening 59. The lens groups 71 and 73 are covered. Also, one flange 65 is aligned with the stepped portion 55 of the attachment body 5 that forms the inner peripheral edge of the opening 59, and the other flange 67 is a reflecting member 9 </ b> A that forms the outer peripheral edge of the opening 59. It is adjusted to the end face.
At this time, as shown in FIG. 7, the end portion of the reflecting surface 41 is extended to the end portion in the major axis direction of each of the elliptic lenses 15 constituting the lens group 73. In addition, one end of the attachment body 5 extends to the end portion in the major axis direction of each of the elliptic lenses 15 constituting the lens group 71.

As shown in FIG. 8A, the optical shaping filter 11 is configured by arranging ten filter pieces 75 arranged in a ring shape. That is, the filter piece 75 includes a lens forming portion 81 constituting the lens group 71 and a lens forming portion 83 constituting the lens group 73, as shown in FIGS. That is, in the lens forming portions 81 and 83, a plurality of elliptic lenses 15 are arranged without gaps in the short axis direction, and the arranged plurality of elliptic lenses 15 are arranged in two rows in the long axis direction.
Further, from the lens forming portion 81, a flange constituting portion 85 constituting the flange 65 is extended, and from the lens forming portion 83, a flange constituting portion 87 constituting the flange 67 is extended.
Thereby, by arranging the filter pieces 75 in an annular shape, the lens groups 71 and 73 arranged in two rows with the major axis direction of the elliptic lens 15 as the column direction, and the flanges 65 and 67 extended from the lens groups 71 and 73. Is formed.

Next, a structure for attaching the light source unit 3 to the case unit 27 will be described.
As shown in FIGS. 4, 5, and 7, the case unit 27 includes a mounting base 31, a base cover 33, and a pressing lid 35. The irradiation device 1 is configured by sandwiching the light source unit 3 disposed in the mounting base 31 between the mounting base 31, the base cover 33, and the pressing lid 35.
The mounting base 31 has a bottomed cylindrical shape. As shown in FIGS. 5 and 7, a through hole 37 for inserting the attachment body 5 is formed at the center of the bottom of the attachment base 31.
The light source unit 3 is coaxially arranged on the mounting base so that the other end surface of the main body 47 is inserted into the through hole 37. Further, a mounting bracket 39 is provided on the bottom outer wall surface of the mounting base 31 at a position covering the through hole 37. The mounting bracket 39 is formed in a U-shaped cross section, and the bottom of the mounting bracket 39 is fixed to the mounting base 31. Further, the other end of the main body portion 47 inserted into the through hole 37 is fixed to the mounting bracket 39.
A terminal block 62 is attached to the bottom outer wall surface of the attachment base 31. Wiring (not shown) is routed so as to connect each terminal of the terminal block 62 and the LED substrate 63. The wiring is a power line for supplying power to the LED board 63 from the outside to turn on the LED 4, and a communication line for sending a signal for controlling the lighting of the LED 4 to the LED board 63. Lighting can be controlled from the outside.

The light shaping filter 11 of the light source unit 3 is fixed to the reflecting member 9 </ b> A and the attachment body 5 using the base cover 33 and the pressing lid 35.
The base cover 33 includes a cylindrical portion 89 and a pressing portion 91 extending to a predetermined width from the entire circumferential area of one end of the cylindrical portion 89 to the inside in the radial direction. The mounting base 31 is fitted into the cylindrical portion 89 of the base cover 33 from the front end side, and a flange 67 is sandwiched between the pressing portion 91 and the end surface of the reflecting member 9A. In this state, the base cover 33 is fixed to the mounting base 31.
A disc-shaped presser lid 35 is provided so as to cover one end surface of the attachment body 5. The outer peripheral portion of the presser lid 35 extends from the outer peripheral edge portion of the main body portion 47. The pressing lid 35 is fixed to one end surface of the main body portion 47 with screws (not shown) in a state where the flange 65 is sandwiched between the outer peripheral portion thereof and the stepped portion 55 of the main body portion 47.
Further, an opening formed between the end portion of the pressing portion 91 of the base cover 33 and the outer peripheral surface of the pressing lid 35 constitutes an emission opening 90 of the irradiation device 1.

By the way, the light source unit 3 of this embodiment has the cooling structure which cools the some LED4 attached to the attachment body 5 efficiently as above-mentioned, and demonstrates the detailed structure below.
As described above, the attachment body 5 is configured by closing the concave portion 51 opened at one end of the main body portion 47 with the lid portion 49.
As shown in FIGS. 1 and 7, a partition plate 93 that divides the space in the recess 51 into two protrudes from the bottom of the recess 51 located on the other end side of the main body 47. The front end of the partition plate 93 is disposed with a gap between the lid portion 49 and a flow path that connects the partitioned spaces 51A and 51B is formed.
Further, the attachment body 5 is attached to the reflection member 9A by fitting the end portion of the attachment body 5 into the fitting insertion hole 43 of the reflection member 9A. A pair of inlet / outlet ports 21 and 23 protrude from the other end surface of the attachment body 5 inserted into the insertion hole 43. The pair of inlet / outlet ports 21 and 23 are inserted into through holes 39 </ b> A provided at the bottom of the mounting bracket 39. One end of the entrance / exit port 21 is inserted into the space 51A, and one end of the entrance / exit port 23 is inserted into the space 51B. Thereby, the flow path 25 which leads from the one inlet / outlet port 21 to the other inlet / outlet port 23 through the space 51A and the space 51B is formed.

Further, a pipe (not shown) for supplying cooling water to the flow path 25 is connected to the other end of the one inlet / outlet port 21, and cooling water is supplied to the other end of the other inlet / outlet port 23. A pipe (not shown) for draining from the pipe is connected.
As described above, since the cooling medium is introduced / discharged from the end of the attachment body 5, the piping for introducing / discharging the cooling water is disposed at a position that does not affect the control light of the optical system 7. .
That is, the pipe attached to the end of the attachment body 5 does not obstruct the light path between the plurality of LEDs 4 attached to the outer peripheral surface of the attachment body 5 and the optical system 7 surrounding the plurality of LEDs 4. Does not affect the control light.
Heat generated by the LED 4 is conducted to the mounting body 5 through the LED substrate 63. As a material of the main body portion 47 constituting the attachment body 5, for example, a material having good thermal conductivity such as copper is used, and the surface of the main body portion 47 is nickel-plated. Thereby, the heat of the LED 4 is efficiently conducted through the main body 47 and reaches the flow path 25. By flowing the cooling water through the flow path 25, the cooling water takes the heat of the mounting body 5 and takes it outside.

Next, the effect of the light source unit 3 of this embodiment will be described in comparison with the light source unit of the comparative example.
FIG. 9 is a principal ray diagram of light produced by the optical system 7 of the light source unit 3. The light ray diagram of FIG. 9 shows only light emitted from one LED 4, but the light ray diagrams of light emitted from other LEDs 4 are the same. FIG. 10 is a ray diagram for explaining the extension in the extending direction V and the width direction W of the ray passing through the elliptic lens 15. FIG. 11 is a diagram showing the illuminance distribution of light produced by the optical systems of the light source unit 3 and the light source units of Comparative Examples 1 and 2. 11A shows the illuminance distribution of the light source unit 3, FIG. 11B shows the illuminance distribution of the light source unit of Comparative Example 1, and FIG. 11C shows the light source unit of Comparative Example 2. Illuminance distribution is shown. The light source unit of Comparative Example 1 is configured in the same manner as the light source unit 3 except that transparent glass is used instead of the light shaping filter 11. The light source unit of Comparative Example 2 is configured in the same manner as the light source unit 3 except that ground glass is used in place of the light shaping filter 11.

As shown in FIGS. 9 and 10, the light from the LED 4 is reflected by the reflecting surface 41 to be substantially parallel light, and then enters the lens groups 71 and 73 of the light shaping filter 11, and enters the lens groups 71 and 73. Controlled and emitted. In the light source unit 3, the outgoing light LF of the light shaping filter 11, in other words, the light generated by the optical system 7 is suppressed from greatly expanding in the width direction with respect to the incident light LP. Moreover, as shown to (A) of FIG. 11, in the light source unit 3, the illumination intensity nonuniformity of the emitted light LF and the result of blurring of an outline were suppressed.
On the other hand, in the light source unit of Comparative Example 1, as shown in FIG. 11B, the outline blur in the width direction W of the emitted light LF is not large, but large illuminance unevenness remains in the emitted light. Further, in the light source unit of Comparative Example 2, as shown in FIG. 11C, although the illuminance unevenness of the emitted light LF was improved, the outline of the emitted light LF was blurred.

Consider the above results.
In the light source unit 3, annular parallel light extending approximately in a predetermined width is generated from the light of the plurality of LEDs 4 arranged in an annular shape by the reflecting member 9 </ b> A, and this light is controlled by the elliptical lens 15. As described above, the incident surface 15A of the elliptic lens 15 has a curvature between both ends in the minor axis direction, and the incident light LP that has been collimated is diffused mainly in the minor axis direction by this curvature. Exit. Since the major axis direction of the elliptical lens 15 is directed to the width direction W of the outgoing light LF of the optical shaping filter 11, the optical shaping filter 11 causes the incoming light LP to be emitted in the direction in which the elliptical lenses 15 are arranged. Are mainly diffused in the extending direction V of the light and emitted. Each of the lights of the plurality of LEDs 4 extends in the extending direction V, and is arranged at a position where both sides of the extending direction are overlapped to form an annular light. The irradiation area EB (see FIG. 10) at the irradiation destination of the light emitted from each LED 4 is roughly set so that only the collimated light has the width of the light emitted through the elliptic lens 15.

Here, as shown in FIG. 10, among the light emitted from each LED 4, the light emitted in a range θw connecting the LED 4 and both ends of the incident surface 15 </ b> A of the elliptical lens 15 in the major axis direction is converted into parallel light. Without going directly to the incident surface 15A. As described above, the incident surface 15A of the elliptic lens 15 has a curvature between both ends in the long axis direction. The curvature between both ends in the major axis direction is set so as to be directed inward in the width direction of the irradiation region EB of each LED 4 by changing the traveling direction with respect to light directly incident on the incident surface 15A from the LED 4. ing. That is, as indicated by a broken line in FIG. 10, the traveling direction of the direct light of the LED 4 that is incident on the incident surface 15A and goes to the range RA outside the irradiation region EB in the width direction is directed into the irradiation region EB. The curvature between both ends in the major axis direction of the incident surface 15A is set so as to be changed.
For this reason, the component of the light which goes to the outer side of the irradiation area | region EB is suppressed, and in the light source unit 3, as shown to (A) of FIG. 11, the illumination intensity nonuniformity of the emitted light LF and the outline blur of the width direction W are enough. It can be judged that it was suppressed.
In the light source unit of Comparative Example 1, the light from the plurality of LEDs 4 arranged in a ring is converted into parallel light and then simply transmitted through the transparent glass. The light of each LED 4 has high illuminance at the center of the light beam. For this reason, the illuminance unevenness remains in the incident light LP after the light of each LED 4 is collimated by the reflecting member 9A. However, since the transparent glass emits the incident light LP as it is, in the light source unit of Comparative Example 1, It can be determined that the illuminance unevenness of the emitted light has increased.
Further, in the light source unit of Comparative Example 2, the annular incident light LP is diffused by ground glass to be emitted light. As a result, the illuminance unevenness of the emitted light is suppressed, but the annular incident light LP incident on the frosted glass is diffused and emitted in a direction other than the circumferential direction, so that the contours on both sides in the width direction of the emitted light are blurred. Can be judged.

  In the light source unit 3 according to the embodiment of the present invention, light obtained by collimating the light of the arranged LEDs 4 is passed through a plurality of elliptical lenses 15 arranged in the width direction of the outgoing light LF produced by the optical system 7. It is emitted. The elliptic lens 15 diffuses and emits the incident light LP in the direction in which the LEDs 4 are arranged in the direction in which the emitted light LF produced by the optical system 7 extends. The blur of the outline in the width direction can be sufficiently suppressed.

Further, the reflection surface 41 of the reflection member 9A is extended to the ends in the major axis direction of the elliptical lenses 15 arranged side by side.
According to this configuration, since there is no light emitted from between the elliptic lens 15 and the reflection surface 41 without passing through the elliptic lens 15, it is possible to further suppress the blur of the outline of the emitted light LF.
Further, the end portion of the attachment body 5 extends to the end portion in the major axis direction of each of the elliptical lenses 15 arranged side by side.
According to this configuration, the light emitted from between the elliptical lens 15 and the attachment body 5 without passing through the elliptical lens 15 is eliminated, so that the outline of the emitted light LF is further suppressed from being blurred.

Moreover, the reflective surface 41 is arrange | positioned surrounding the attachment body 5 in which several LED4 was attached along with the outer peripheral surface, and the attachment body 5 is attached to the reflection member 9A by fitting.
According to this configuration, since the attachment body 5 is attached to the reflecting member 9A by fitting, the assemblability of the light source unit 3 can be improved.

In addition, a cooling medium flow path 25 is provided inside the columnar attachment body 5.
According to this configuration, the plurality of LEDs 4 can be cooled simultaneously and evenly by a simple structure in which the cooling medium flow path 25 is provided inside the attachment body 5 in which the LEDs 4 are attached to the outer peripheral surface. Each LED 4 can be cooled well.
In addition, the cooling medium is introduced into and discharged from the flow path 25 from the end of the attachment body 5 that is fitted into the fitting hole 43 of the reflecting member 9 </ b> A constituting the optical system 7.
According to this configuration, since the cooling medium is introduced / discharged from the end of the attachment body 5, for example, compared with introduction / discharge from the outer peripheral surface of the attachment body 5, the control of the reflection member 9 </ b> A surrounding the attachment body 5 is controlled. Piping for introducing / discharging the cooling medium can be collectively arranged at a position where the light is not affected.

The above-described embodiment is merely an example of one aspect of the present invention, and can be arbitrarily modified and applied without departing from the spirit of the present invention.
For example, in the above-described embodiment, the optical system 7 has been described as generating an annular light, but it may be a light that extends in a straight line with a predetermined width or a light that extends in a curved line with a predetermined width. .
Moreover, although LED4 was illustrated as an example of a light emitting element, it is not restricted to this, Other light emitting elements, such as organic EL, may be sufficient.
Moreover, although demonstrated as what is LED4 and ultraviolet LED which radiate | emits an ultraviolet-ray, you may use what radiate | emits a different kind of light according to the use of the light source unit 3 irrespective of what emits an ultraviolet-ray.
Moreover, although the elliptical lenses 15 were described as being arranged without gaps, gaps may be provided to some extent. Even in this case, not all the effects of suppressing the illuminance unevenness and the outline blur of the emitted light LF are lost.

DESCRIPTION OF SYMBOLS 1 Irradiation device 3 Light source unit 4 LED (light emitting element)
5 Mounting body 7 Optical system 9 Parallelizing member (parallelizing means)
9A Reflective member (parallel light means)
15 Ellipse lens 41 Reflecting surface

Claims (5)

A plurality of light emitting elements arranged,
An optical system that controls the light of each of the light emitting elements and extends in the direction in which the light emitting elements are arranged to suppress light unevenness, and
The optical system is
A reflective surface for collimating the light of the light emitting element;
A plurality of elliptical lenses on which the parallel light from the reflecting surface and the direct light of the light emitting element are incident ;
Each of the elliptical lenses has a concave entrance surface, and
A long axis direction is directed to the width direction of the light extending , a short axis direction is directed to the light extending direction, and arranged in a line in the light extending direction, and the parallel light is diffused in the short axis direction. Exit,
The light source unit characterized in that the curvature in the major axis direction of the incident surface is a curvature that directs the direct light within the width of the parallel light in the irradiation region . The light source unit according to claim 1, characterized in that pre-Symbol reflecting surfaces, extended to the end portion of each of the long axis direction of the side by side arranged the elliptical lens. An attachment body to which the light emitting element is attached;
3. The light source unit according to claim 1, wherein the ends of the attachment body are extended to the ends in the major axis direction of the elliptic lenses arranged side by side. Extending the reflecting surface to the end in the major axis direction of each of the elliptical lenses arranged side by side,
An attachment body to which the light emitting element is attached;
Extend the end of this mounting body to the end of each of the elliptical lenses arranged side by side,
The mounting body is columnar, and a plurality of the light emitting elements are arranged side by side on the outer peripheral surface of the mounting body,
The reflective surface is provided so as to surround the attachment body and face the outer peripheral surface,
The light source unit according to claim 1 , wherein the attachment body is attached to the reflection surface by fitting.   An irradiation apparatus comprising the light source unit according to claim 1.