TW201634859A - Light irradiation apparatus - Google Patents

Abstract

To provide a light irradiation apparatus capable of cutting off light having an unnecessary wavelength for an irradiation range with high precision by a configuration of using a wavelength selection filter having incidence angle dependency. A light irradiation apparatus includes a wavelength selection filter 33 which transmits light having a necessary wavelength for an irradiation range and an absorption filter 35 which absorbs light having a wavelength outside of a range of the necessary wavelength, and irradiates light transmitted through the wavelength selection filter 33 and the absorption filter 35 to a work W as the irradiation range.

Description

Light irradiation device

The present invention relates to a light irradiation device that irradiates light that penetrates a wavelength selective filter to an irradiation region.

There is known a photohardening technique which has been widely applied to packaging of liquid crystal panels, adhesion of optical lens components, adhesion of optical disks, temporary fixing of components of printed circuit boards, etc., which is usually applied with a light hardener. Cover the surface of paper or plastic, and then light the light hardener to harden it. The light used for photohardening differs depending on the kind of hardener, hardening conditions, etc., and visible light or near-infrared rays may be used in addition to ultraviolet rays (ultraviolet light). In the case where the light source of the light irradiation device used in the photo-curing technique is used for photocuring, a discharge lamp such as a high-pressure mercury lamp or a metal halide lamp is usually used (for example, see Patent Document 1). In order to avoid the thermal influence from the light source as much as possible, the light irradiation device is provided with a heat-ray cut filter that shields the visible light and the near-infrared rays that are not required for the irradiation region (for example, refer to Patent Document 2).

[Previous Technical Literature] [Patent Literature]

Patent Document 1: Japanese Patent No. 4642066

Patent Document 2: Japanese Patent Laid-Open Publication No. 2007-191543

However, the cut-off filter is a wavelength selective filter in which a dielectric multilayer film is laminated on a transparent substrate, and has an incident angle dependency on the penetration characteristics. Therefore, in the case where the wavelength required for the irradiation region is adjusted by only the cut filter, there is a problem that the light obliquely incident on the filter is irradiated to the irradiation region by the unnecessary wavelength.

The present invention has been made in view of the above circumstances, and it is an object of the invention to provide a light-irradiating device capable of selectively shielding light having a wavelength unnecessary for an irradiation region by using a wavelength selective filter having an incident angle dependency.

In order to achieve the above object, the present invention provides a light irradiation device including a light source that emits light having a wavelength required for an irradiation region, and a wavelength selective filter that transmits light including the wavelength required, from the light source Light passing through the wavelength selective filter is irradiated to the irradiation region; wherein the light irradiation device is provided with an absorption filter that absorbs light outside the range of the required wavelength, and penetrates the wavelength selection filter The light of the optical device and the absorption filter is irradiated to the irradiation region.

Furthermore, the present invention is directed to the light irradiation device described above, wherein the absorption filter is configured to allow light incident through the wavelength selective filter to be incident.

Further, the present invention is directed to the light irradiation device, comprising: a mirror that reflects light from the light source such that light from the light source is within an angle range including an incident angle of inclination It is incident on the above wavelength selection filter.

Furthermore, the present invention is directed to the light irradiation device characterized in that the wavelength selective filter is a filter having an incident angle dependency, and the absorption filter The light device is a filter that does not have an incident angle dependency.

Furthermore, the present invention is directed to the light irradiation device characterized in that the absorption filter is a filter having a light absorbing material, and the light absorbing material absorbs a penetration band that is less than the wavelength selective filter. Light in the lower wavelength range.

Furthermore, the present invention is directed to the above-mentioned light-irradiating device, characterized in that a spacer is interposed between the wavelength selective filter and the absorption filter, and the spacer is selected to pass through the wavelength selective filtering. The light that is disposed on the light source side filter and the light incident on the other filter in the absorption filter is shielded from light.

Further, according to the present invention, in the light irradiation device, the wavelength selective filter and the absorption filter are configured by arranging a plurality of filters in a direction in which the respective filters extend, and the lining. The pad has a boundary light blocking portion extending along a boundary portion between the plurality of filters constituting the wavelength selective filter and the filter disposed on the light source side of the absorption filter, The light leaking from the boundary portion is shielded from light.

Further, the present invention is directed to the light irradiation device, comprising: a housing for accommodating the light source and the wavelength selective filter; and an illumination opening provided in the housing, comprising the wavelength selective filter; The cover unit of the above absorption filter is sealed.

According to the present invention, a wavelength selective filter for transmitting light having a wavelength required for an irradiation region is provided, and an absorption filter for absorbing light outside a required wavelength range is provided, and a wavelength selective filter is penetrated and Since the light of the absorption filter is irradiated to the irradiation region, the filter having the wavelength dependence of the incident angle can be selected, and the light of the wavelength unnecessary for the irradiation region can be shielded with high precision.

1‧‧‧Lighting device

2‧‧‧Outer casing (box)

2K‧‧‧ openings (irradiation openings)

2R‧‧ Track

11‧‧‧Irradiation unit

12‧‧‧ Straight tube type lamp (light source)

12S‧‧‧light support

13‧‧‧Mirror unit

13A‧‧‧ Hole Department

14‧‧‧ frame

15‧‧‧light storage box

21‧‧‧Cooling unit

21A‧‧‧Cooling radiator

21B‧‧‧Cooling unit

21C‧‧‧cooling blower

31‧‧‧ cover unit

31A‧‧‧ Opening

32‧‧‧ frame cover

32A‧‧‧Bars

33‧‧‧wavelength selection filter

33A‧‧‧Filter

34‧‧‧ cushion

34A‧‧‧Boundary Shading Department

35‧‧‧ absorption filter

36‧‧‧Filter presser

37‧‧‧ fastening members

Spectroscopic characteristics of f1‧‧‧ wavelength selective filter

Spectral characteristics of f2‧‧‧ absorption filter

W‧‧‧Workpiece (illuminated area)

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

Fig. 2 is a schematic view showing an irradiation unit of a light irradiation device.

Fig. 3 is an exploded perspective view of the cover unit of the light irradiation device.

Fig. 4 is a view showing the spectral characteristics of the wavelength selective filter and the absorption filter.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Fig. 1 is a view showing a light irradiation device 1 of an embodiment. The light irradiation device 1 is a device that illuminates visible light toward a material that is hardened by visible light, and is disposed above the workpiece W that is an irradiation surface of the object, and uniformly irradiates the workpiece W with visible light of 390 nm to 500 nm (visible). A device for light on the short wavelength side of light. The casing 2 constituting the outer casing of the light irradiation device 1 houses an irradiation unit 11, a cooling unit 21 that cools the irradiation unit 11, and a cover unit 31 that is disposed between the irradiation unit 11 and the workpiece W.

FIG. 2 is a schematic view showing the irradiation unit 11. The irradiation unit 11 includes a straight tube type bulb 12 constituting a light source, and a mirror unit 13 that reflects light emitted from the straight tube type bulb 12 (light shown by a broken line in FIG. 2) toward the lower side (the workpiece W side). This mirror unit 13 is supported by a frame 14 extending in the longitudinal direction of the straight tube type bulb 12. The straight tube type lamp 12 is, for example, a gallium lamp in which a halide of gallium is enclosed in an arc tube, a large amount of a wavelength region of 400 to 450 nm is output, and a long straight tube type lamp extending substantially in parallel along the workpiece W is used. The straight tube type lamp 12 can be widely applied to various light sources, for example, a high pressure mercury lamp or other metal halide lamps can also be applied. The lamp support 12S supporting the straight tube type lamp 12 is coupled to the cover unit 31.

The mirror unit 13 is formed as a concave mirror that is recessed upward, and will The straight tube type lamp 12 is open directly below the straight tube type lamp tube 12 and extends along the longitudinal direction of the straight tube type tube 12. The mirror unit 13 covers the entire length of the straight tube type lamp 12 from above, so that the direct light that is not emitted from the straight tube type tube 12 to the workpiece W is reflected toward the workpiece W. By providing the mirror unit 13, the amount of light irradiated to the workpiece W can be increased, and the utilization efficiency of the light of the straight tube type lamp 12 can be improved. Further, the mirror unit 13 is slidably supported by one of the rails 2R extending in the longitudinal direction of the straight tube type lamp 12, so that the mirror unit 13 can be easily moved to a maintenance such as exchange. position.

The outer casing 2 is formed of a metal case having an opening 2K that opens downward, and a cooling radiator 21A, a cooling unit 21B, a cooling blower 21C, and the like are provided above the mirror unit 13. The cooling radiator 21A, the cooling unit 21B, and the cooling fan 21C constitute a component of the cooling unit 21, and the cooling air blower 21C blows the cooling air toward the irradiation unit 11, and the respective portions of the irradiation unit 11 (straight tube type) The lamp tube 12, the mirror unit 13, and the like are air-cooled. Further, the cooling radiator 21A and the cooling unit 21B cool the cooling fluid supplied to the plurality of holes 13A provided in the mirror unit 13, respectively. The plurality of holes 13A extend in the longitudinal direction of the mirror unit 13, and the mirror unit 13 can be efficiently cooled by flowing the cooling fluid to each of the holes 13A.

Thereby, the respective portions of the irradiation unit 11 (the straight tube type lamp tube 12, the mirror unit 13, and the like) can be forcibly cooled, and the straight tube type lamp caused by the heat of the straight tube type tube 12 can be sufficiently suppressed. The temperature of the tube 12, the mirror unit 13, and the like rises. Further, the opening portion 2K of the lamp housing box 15 is covered by the cover unit 31. Therefore, the lamp housing box 15 can be separated from the external space, and the thermal influence of the external space can be suppressed, and independent cooling can be formed in the lamp housing box 15. space.

The cover unit 31 is a cover member that covers the opening portion 2K below the outer casing 2, and is formed into a rectangular thin cover that extends in the longitudinal direction of the straight tube type bulb 12. A rectangular opening portion 31A extending along the longitudinal direction of the straight tube type bulb 12 is formed directly under the cover unit 31 and the straight tube type lamp tube 12, by direct light of the straight tube type tube 12, and Light is reflected by the mirror unit 13 and passes through the opening 31A to illuminate the workpiece W. In other words, the opening 31A of the outer casing 2 functions as an irradiation opening that irradiates the workpiece W with light. Further, the cover unit 31 is attached so as to be easily detachable from the outer casing 2. Since the straight tube type lamp 12 is supported by the cover unit 31 via the lamp support body 12S, the cover unit 31 and the straight tube type lamp tube 12 can be easily detached from the outer casing 2.

In the light of the straight tube type lamp 12, light having a wavelength that does not need to be irradiated to the workpiece W is further included, and in order to remove the unnecessary wavelength light, the opening portion 31A is attached to the opening portion 31A of the cover unit 31. The wavelength selection filter 33. The wavelength selective filter 33 is an optical filter formed by laminating a dielectric multilayer film on a transparent substrate, and is only required to pass light of a wavelength (required wavelength) required for irradiation of the workpiece W, and light of an unnecessary wavelength is not Will penetrate. Thereby, the wavelength selective filter 33 functions as a cut filter that removes unnecessary light of the workpiece W.

However, the wavelength selective filter 33 has an incident angle dependency on the transmission characteristics. Therefore, for obliquely incident light, even if it is an unnecessary wavelength, a part of light penetrates. In particular, in the light irradiation device 1 of the present embodiment, the flat-wavelength selective filter 33 is disposed at a position separated from the straight tube type bulb 12, and the curved mirror unit 13 is used for the straight tube type lamp 12 Since the light is reflected, as shown in FIG. 2, there are many light components obliquely incident on the wavelength selective filter 33, and it is easy to increase the wavelength of the unnecessary wavelength that penetrates the wavelength selective filter 33. Therefore, In the present configuration, an absorption filter 35 that absorbs light of an unnecessary wavelength is further provided, and only light having a necessary wavelength that penetrates the wavelength selective filter 33 and the absorption filter 35 is irradiated to the illumination. The area is the workpiece W.

FIG. 3 is an exploded perspective view showing the cover unit 31. As shown in FIG. 3, the cover unit 31 includes a frame cover 32 that forms an opening 31A, a wavelength selective filter 33, a spacer 34, and an absorption filter 35, which are laminated on the frame cover 32; The filter presser 36 fixes the wavelength selective filter 33, the spacer 34, and the absorption filter 35 to the frame cover 32. The wavelength selection filter 33 and the absorption filter 35 are formed in a rectangular flat plate shape slightly larger than the opening portion 31A, and are formed in the same outer shape in the present embodiment.

The frame cover 32 and the filter presser 36 are formed of a material having rigidity such as metal or resin. A ridge portion 32A is disposed on the upper surface of the frame cover 32 so as to form a continuous rectangular frame along the outer edge of the opening portion 31A. Further, the filter pressing member 36 is configured to sandwich the wavelength selection filter 33, The lining portion 34 and the absorbing filter 35 are disposed on the rib portion 32A from above, and the filter press member 36 is fixed to the frame cover 32 by a plurality of fastening members (fixing bolts in the present configuration) 37. . Thereby, the wavelength selective filter 33, the spacer 34, and the absorption filter 35 are interposed between the frame cover 32 and the filter presser 36. In the present configuration, since the wavelength selective filter 33 and the absorption filter 35 are integrally formed in the cover unit 31, the plurality of filters 33 and 35 can be easily attached or detached to the irradiation unit 11. Further, since the plurality of filters 33 and 35 are arranged substantially in a superposed manner, the height of the cover unit 31 having the plurality of filters 33 and 35 can be suppressed, and the increase in the height of the light irradiation device 1 can be suppressed.

The spacer 34 is a gap adjusting member for ensuring a gap between the wavelength selective filter 33 and the absorption filter 35 in an overlapping configuration, which is made of PTFE (polytetrafluoroethylene) A material having light blocking properties and flexibility such as alkene is formed. By the minute gap, even if an external force acts on a filter 33 or 35, the contacts of the filters 33 and 35 can be prevented from each other, and the transmission of the external force can be suppressed. In particular, in the case where a transparent glass material (quartz glass, borosilicate glass, or the like) which has an ultraviolet-resistant material and has a high transmittance is used for the substrate of the wavelength selective filter 33 and the absorption filter 35, By providing the spacer 34, even if these are laminated, it is possible to effectively suppress damage or the like of the glass material due to the influence of an external force.

Further, the spacer 34 is formed in a frame shape along the outer edge of the wavelength selection filter 33 so as to at least shield the gap around the wavelength selective filter 33 disposed on the side of the straight tube type bulb 12. Therefore, it is possible to surely prevent the light of the straight tube type bulb 12 from leaking from the periphery of the wavelength selection filter 33 and entering the absorption filter 35 disposed on the workpiece W side.

Further, as shown in FIG. 3, the wavelength selective filter 33 on the side of the straight tube type bulb 12 is configured to arrange a plurality of filters 33A in the longitudinal direction of the straight tube type tube 12. And the light from the straight tube type lamp 12 may be incident on the minute gap between the filters 33. In the present embodiment, the spacer 34 integrally includes a boundary light blocking portion 34A extending along a boundary portion of the plurality of filters 33A (small pieces) constituting the wavelength selective filter 33 so that light leaking from the boundary portion is not incident on the arrangement. The absorption filter 35 on the side of the workpiece W. In other words, the spacer 34 functions as a light shielding member that blocks light that is incident on the absorption filter 35 without penetrating the wavelength selective filter 33, and can suppress deterioration of the light absorbing material of the absorption filter 35. Further, the light emitted from the straight tube type lamp 12 contains ultraviolet light, and since the ultraviolet light is suppressed from being irradiated to the absorption filter 35 by the spacer 34, ultraviolet light deterioration of the light absorbing material can be suppressed. Thereby, the performance deterioration of the absorption filter 35 can be effectively suppressed, and the life can be prolonged. Furthermore, it can also The wavelength selective filter 33 is configured as a single plate type. In the case of the single-plate type, the boundary light-shielding portion 34A of the spacer 34 may be omitted or deleted. In the case where it is not deleted, it is easier to appropriately maintain the gap between the wavelength selective filter 33 and the absorption filter 35 in the number of the boundary light blocking portions 34A.

4 shows the spectral characteristics of the wavelength selective filter 33 and the absorption filter 35. In Fig. 4, the symbol f1 shows the spectral characteristics of the wavelength selective filter 33, and the symbol f2 shows the spectral characteristics of the absorption filter 35. Further, the spectral characteristics of the wavelength selective filter 33 shown in Fig. 4 are the transmittance characteristics under normal incidence. As shown by the symbol f1 in FIG. 4, in the transmittance characteristic of normal incidence, the wavelength selective filter 33 is a penetration band having a maximum transmittance of 85% or more in the wavelength range of 390 to 500 nm, at 600~. At least a portion of the wavelength range of 800 nm has a visible region having a maximum transmittance of 1% or less and a cutoff band at a near-infrared light side, and an ultraviolet side having a maximum transmittance of 1% or less in at least a portion of a wavelength range of 200 to 400 nm. Cutoff band. Further, by forming the transparent substrate from quartz glass which is a material having high heat resistance, the heat resistance of the wavelength selective filter 33 can be improved.

Specifically, the wavelength selective filter 33 is formed on a different surface of a transparent substrate made of quartz glass, and has a first layered body constituting a narrow-band pass type (NBP type) filter and a wide-band type. The second layer of the filter of the (BBP type) is a first layered body, and constitutes a penetration band and a penetration band having a maximum transmittance of 85% or more in a wavelength range of 400 to 600 nm. The transmittance on the short-wavelength side is from 85% to 5%, and the transmittance on the long-wavelength side is from 85% to 5%. Further, the second layered body of the NBP type forms a visible region having a minimum transmittance of 1% or less and a near-infrared light-side cutoff band in at least a part of a wavelength range of 600 to 800 nm, and a wavelength of 200 to 400 nm. At least part of the scope The ultraviolet side cutoff band having a minimum transmittance of 1% or less is formed.

The absorption filter 35 is an optical filter formed by dispersing a light absorbing material that absorbs light of a predetermined wavelength in a transparent substrate (such as quartz glass or borosilicate glass), and is formed in the same manner as the wavelength selective filter 33. It is a rectangular flat plate shape that covers the opening portion 31A of the cover unit 31. As shown by the symbol f2 in Fig. 4, the absorption filter 35 is set to penetrate light in a wavelength range (390 to 500 nm) in which the transmittance of the wavelength selective filter 33 is set high, and absorbs it. The light of a predetermined wavelength is a characteristic of light of a wavelength that is not required for the workpiece W. The absorption filter 35 does not have an incident angle dependency.

More specifically, the absorption filter 35 is a penetration band having a wavelength range of less than 390 nm as an absorption band and a wavelength range of 390 nm or more as a maximum transmittance of 90% or more. Thereby, the absorption filter 35 can absorb the light having a wavelength of less than 390 nm which is penetrated by the wavelength selective filter 33 by oblique incidence. Further, as shown in FIG. 3, the absorption filter 35 is also configured in a multi-plate type arranged in the longitudinal direction of the straight tube type bulb 12, similarly to the wavelength selective filter 33. Therefore, compared with the case where the wavelength selection filter 33 and the absorption filter 35 which are formed in the longitudinal direction of the straight tube type bulb 12 with one part are selected, it can be manufactured easily and at low cost.

According to the above configuration, as shown in FIG. 2, the light radiated from the straight tube type lamp 12 is directly or reflected by the mirror unit 13 and is incident on the wavelength selective filter 33 at various incident angles. The light incident vertically is in accordance with the optical characteristics of the wavelength selective filter 33 (reference symbol f1 in Fig. 4), and the light having a wavelength range (390 to 500 nm) set to a high transmittance is penetrated, and the wavelength is other than this. Light hardly penetrates. The light that has passed through the wavelength selective filter 33 is incident on the workpiece W by penetrating the absorption filter 35 because it is in the wavelength range of the high transmittance of the absorption filter 35.

On the other hand, the light incident on the wavelength selective filter 33 is obliquely A part of the light passes through the wavelength selective filter 33 in accordance with the incident angle dependency of the wavelength selective filter 33. After the transmitted light is incident on the absorption filter 35, the optical characteristics of the absorption filter 35 (refer to reference numeral f2 in Fig. 4) are passed, and light having a wavelength range (390 nm~) set to a high transmittance is penetrated. Light of a wavelength range (less than 390 nm) set to a low transmittance is absorbed by the absorption filter 35. Thereby, the two wavelength filters of the wavelength selective filter 33 and the absorption filter 35 are configured to illuminate the workpiece W in a wavelength range (390 to 500 nm) required for the workpiece W, and the workpiece can be accurately guided. The light is not covered by the wavelength range (especially below 390 nm).

Further, in the above-described two-stage filter configuration, only the light that has passed through the wavelength selective filter 33 is incident on the absorption filter 35, so that the deterioration of the light absorbing material of the absorption filter 35 can be suppressed, and the absorption filter can be suppressed. The performance of the optical device 35 deteriorates.

As described above, in the present embodiment, the wavelength selective filter 33 for transmitting light having a wavelength required for the irradiation region is provided, and the absorption filter 35 for absorbing light outside the required wavelength range is provided. Further, since the light that has passed through the wavelength selective filter 33 and the absorption filter 35 is irradiated onto the workpiece W which is the irradiation region, the filter can be selected with high accuracy using the wavelength selection filter 33 having the incident angle dependency. The light of the unnecessary wavelength of the irradiation area is shielded, and the light of the desired wavelength can be irradiated with high precision.

Further, the absorption filter 35 is disposed such that light passing through the wavelength selective filter 33 is incident, so that the amount of light incident on the absorption filter 35 can be suppressed. Thereby, the deterioration of the performance of the absorption filter 35 can be suppressed, and the life of the absorption filter 35 can be prolonged. As described above, in the present configuration, by configuring the wavelength selective filter 33 in the first stage and the multi-segment filter in which the absorption filter 35 is disposed in the second stage, the wavelength of the unnecessary wavelength of the irradiation region can be accurately performed. The shadowing is expected, and the longevity of the absorption filter 35 can be expected.

However, as long as the life of the absorption filter 35 can be sufficiently ensured, the absorption filter 35 can be disposed on the side of the straight tube type bulb 12 of the wavelength selection filter 33. According to this configuration, since only the light of the wavelength range penetrating the absorption filter 35 is incident on the wavelength selective filter 33, the light of the wavelength range absorbed by the absorption filter 35 is not irradiated onto the workpiece W.

Further, since the mirror unit 13 is provided, the light of the straight tube type lamp 12 is reflected by the mirror unit 13 so that the light is incident on the wavelength selective filter 33 within an angular range including the incident angle of inclination, so that The mirror unit 13 can be used while improving the light use efficiency while avoiding the disadvantages caused by an increase in unnecessary light components that are obliquely incident and penetrate the wavelength selective filter 33 by using the mirror unit 13.

Further, the straight tube type lamp 12 and the wavelength selective filter 33, which are light sources, are housed in a casing constituting the outer casing 2, and include an opening portion 2K provided in the irradiation opening of the casing, and is provided with wavelength selective filtering. Since the lid unit 31 of the absorbing filter 35 and the absorbing filter 35 are closed, the wavelength selective filter 33 and the absorbing filter 35 can be unitized and can be easily attached and detached. Therefore, maintenance such as attachment or detachment of the wavelength selective filter 33 and the absorption filter 35 can be easily performed. Further, since the outer casing 2 can be separated from the surrounding by the cover unit 31, the surrounding heat can be suppressed, and an independent cooling space can be formed in the outer casing 2, whereby the cooling in the outer casing 2 can be efficiently performed.

Further, the cover unit 31 is disposed between the wavelength selective filter 33 and the absorption filter 35, and is disposed on the other side of the light source side (wavelength selection filter 33). The light of the filter (absorption filter 35) is shielded by the light-shielding pad 34, so that light that is not required to be irradiated through the light source side filter (wavelength selective filter 33) can be suppressed from being irradiated to the irradiation area. And the performance of the absorption filter 35 is deteriorated. In addition, since the spacer 34 is interposed, the wavelength selective filter 33 can be surely The absorption filters 35 are disposed with a gap therebetween, and the contact of the filters 33 and 35 with each other can be suppressed.

The above-described embodiments are merely examples of the embodiments of the present invention, and may be arbitrarily modified and applied without departing from the spirit and scope of the invention. For example, although the case where the wavelength selection filter 33 and the absorption filter 35 are integrally formed in the cover unit 31 has been described, the present invention is not limited thereto, and either or both of the filters 33 and 35 may be used. It is disposed at a different position from the cover unit 31. In other words, each of the filters 33 and 35 may be disposed such that light passing through the wavelength selective filter 33 and the absorption filter 35 is irradiated onto the irradiation region. Further, an anti-reflection film may be provided on the surface of the absorption filter 35 to suppress the light component reflected by the absorption filter 35.

Further, although the configuration of the two-stage filter which is the wavelength selection filter 33 and the absorption filter 35 has been described, other optical filters may be disposed on the light source side or on the opposite side of the light source. It is composed of three or more filters. However, the above two-stage filter is most advantageous in terms of ensuring light transmittance.

Further, the light source of the light irradiation device 1 may be a straight tube type lamp in which two or more tube axes are coaxially arranged in series to form two or more tubes. Further, a light source in which light-emitting elements such as LEDs are arranged may be employed.

11‧‧‧Irradiation unit

12‧‧‧ Straight tube type lamp (light source)

13‧‧‧Mirror unit

15‧‧‧light storage box

31‧‧‧ cover unit

33‧‧‧wavelength selection filter

35‧‧‧ absorption filter

W‧‧‧Workpiece (illuminated area)

Claims (8)

A light irradiation device comprising: a light source that emits light having a wavelength required for an irradiation region; and a wavelength selective filter that transmits light including a wavelength required thereby, and penetrates the wavelength selective filter from the light source The light is incident on the irradiation region; and is characterized in that: an absorption filter is provided which absorbs light outside the range of the wavelength required; and light that penetrates the wavelength selective filter and the absorption filter is irradiated Irradiation area. The light irradiation device of claim 1, wherein the absorption filter is configured to be incident on light passing through the wavelength selective filter. A light irradiation device according to claim 1 or 2, further comprising: a mirror that reflects light from said light source such that light from said light source is incident on said angle within an angle range including an oblique incident angle Wavelength selection filter. The light irradiation device according to any one of claims 1 to 3, wherein the wavelength selective filter is a filter having an incident angle dependency, and the absorption filter is a filter having no incident angle dependency. . The light irradiation device of claim 4, wherein the absorption filter is a filter having a light absorbing material, and the light absorbing material absorbs a wavelength range that is less than a lower limit of a penetration band of the wavelength selective filter. Light. The light-irradiating device according to any one of claims 1 to 5, wherein a spacer is interposed between the wavelength selective filter and the absorption filter, and the spacer is paired with the wavelength selective filter. The light that is disposed on the light source side and the light that is incident on the other filter in the light absorbing filter and the light absorbing filter is shielded from light. The light irradiation device of claim 6, wherein the wavelength selective filter and the absorption filter are configured by arranging a plurality of filters in a direction in which the respective filters extend, wherein the spacer has a boundary light shielding portion The boundary light-blocking portion extends along a boundary portion of the plurality of filters constituting the wavelength selective filter and the filter disposed on the light source side of the absorption filter, and leaks light from the boundary portion Shading. The light irradiation device according to any one of claims 1 to 7, wherein the housing having the light source and the wavelength selective filter is provided in the illumination opening of the housing, and the wavelength selection filter is provided And the cover unit of the above absorption filter is sealed.