JP6935238B2 - Lighting device - Google Patents

Description

The present invention relates to a lighting device that illuminates an irradiated surface using a plurality of light emitting elements such as LEDs (light emitting diodes).

An exposure apparatus is used to manufacture a semiconductor element, a liquid crystal substrate, or the like. In this exposure apparatus, in order to uniformly illuminate a large-area exposure area, an illumination apparatus having a basic configuration of a mercury lamp, a condenser mirror, a fly-eye lens and a concave mirror is widely used (see, for example, Patent Document 1). .. In the apparatus described in Patent Document 1, the exposure light emitted from the mercury lamp is incident on the fly-eye lens via the condenser mirror and the plane mirror. Then, the light that has passed through the fly-eye lens is irradiated to the exposed irradiation surface through the concave mirror. As a result, the exposed irradiation surface is uniformly and stably illuminated.

Japanese Unexamined Patent Publication No. 2014-13303

However, in the above-mentioned lighting device, a mercury lamp is used as a light source, and it is inevitable that the lighting device becomes large in size, which is one of the main factors for increasing the size of the exposure device equipped with the lighting device. ..

The present invention has been made in view of the above problems, and an object of the present invention is to provide a technique capable of stably illuminating a lighting device while reducing the size of the lighting device.

A first aspect of the present invention is an illuminating device that irradiates light emitted from an irradiation unit via a collimating optical system, in which the irradiation unit emits a plurality of light emitting elements and an incident surface for each light emitting element. A plurality of rod lenses arranged toward the side and the exit surface toward the collimating optical system side, a lens holding portion that holds the plurality of rod lenses in a state of being separated from each other, and a plurality of rods with respect to the lens holding portion. The rod lens has a polygonal cone trapezoidal shape in which the cross-sectional area expands from the incident surface to the exit surface, and the lens holding portion is mainly on the incident side facing the light emitting element. A flat plate member having a surface and a main surface on the exit side facing the collimating optical system, a plurality of holding through holes provided for each rod lens so that an end on the exit surface side can be fitted, and an inner wall of the holding through hole. Of these, there is a groove provided in the region corresponding to the ridgeline of the rod lens, and the lens fixing portion is an adhesive filled between the holding through hole and the side surface of the rod lens, and is one of the side surfaces of the rod lens. The end portion on the exit surface side is engaged with and supported by the lens holding portion, and is fixed to the lens holding portion by the lens fixing portion .
A second aspect of the present invention is an illuminating device that irradiates light emitted from an irradiation unit via a collimating optical system, in which the irradiation unit has a plurality of light emitting elements and an incident surface for each light emitting element. A plurality of rod lenses arranged toward the light emitting element side and the exit surface toward the collimating optical system side, a lens holding portion that holds the plurality of rod lenses in a state of being separated from each other, and a plurality of rod lenses with respect to the lens holding portion. The rod lens has a tapered shape in which the cross-sectional area expands from the entrance surface to the exit surface, and the lens holding portion is mainly on the entrance side facing the light emitting element. It has a flat plate member having a surface and a main surface on the exit side facing the collimating optical system, and a plurality of holding through holes provided for each rod lens so that an end portion on the exit surface side can be fitted. It is an adhesive filled between the holding through hole and the side surface of the rod lens. In the lens holding portion, the inner wall of the holding through hole has an inverted tapered shape in which the cross-sectional area decreases from the entrance surface to the exit surface. It is characterized in that the end portion of the side surface of the rod lens on the exit surface side is engaged with and supported by the lens holding portion and is fixed to the lens holding portion by the lens fixing portion.
A third aspect of the present invention is an illumination device that irradiates light emitted from an irradiation unit via a collimating optical system, in which the irradiation unit has a plurality of light emitting elements and an incident surface for each light emitting element. A plurality of rod lenses arranged toward the light emitting element side and the exit surface toward the collimating optical system side, a lens holding portion that holds the plurality of rod lenses in a state of being separated from each other, and a plurality of rod lenses with respect to the lens holding portion. The rod lens has a polygonal cone trapezoidal shape in which the cross-sectional area expands from the incident surface to the exit surface, and the lens holding portion is incident facing the light emitting element. It has a flat plate member having a side main surface and an exit side main surface facing the collimating optical system, and a plurality of holding through holes provided for each rod lens so that an end portion on the exit surface side can be fitted, and the lens is fixed. The unit has a rod hold plate provided with a fixing through hole that can be engaged with the ridgeline of the rod lens for each rod lens, and the lens holding portion is provided from the incident surface while making the fixing through hole correspond to the rod lens. It is characterized in that a rod hold plate whose ridge line engages with the inner peripheral surface of the fixing through hole is attached to the lens holding portion and fixed by being attached to the lens holding portion.
A fourth aspect of the present invention is an illuminating device that irradiates light emitted from an irradiation unit via a collimating optical system, in which the irradiation unit has a plurality of light emitting elements and an incident surface for each light emitting element. A plurality of rod lenses arranged toward the light emitting element side and the exit surface toward the collimating optical system side, a lens holding portion that holds the plurality of rod lenses in a state of being separated from each other, and a plurality of rod lenses with respect to the lens holding portion. The rod lens has a tapered shape in which the cross-sectional area expands from the incident surface to the exit surface, and the lens holding portion is mainly on the incident side facing the light emitting element. It has a flat plate member having a surface and a main surface on the exit side facing the collimating optical system, and a plurality of holding through holes provided for each rod lens so that an end portion on the exit surface side can be fitted. Each rod lens has a rod lens holder provided with a through hole for play insertion that allows the rod lens to be loosely inserted, and is attached to the lens holding portion from the incident surface while making the through hole for play insertion correspond to the rod lens. The rod lens holder is attached to the lens holding portion, and the end portion on the incident surface side is fixed to each rod lens with respect to the play-insertion through hole provided in the rod lens holder.

In the invention configured as described above, the plurality of light emitting elements and the plurality of rod lenses are arranged in a one-to-one-to-one correspondence relationship. Here, focusing on one light emitting element, an optical element that irradiates the light emitting light emitted from the light emitting element toward the collimating optical system by the light emitting element and the rod lens corresponding to the light emitting element (hereinafter, "unit irradiation"). "Department") is composed. Then, light is incident on the collimating optical system for each unit irradiation unit, and a number of lights corresponding to the number of unit irradiation units are collimated by the collimating optical system. In this way, it is possible to illuminate the irradiation surface over a wide range using a plurality of light emitting elements as light sources, and the device can be downsized as compared with the conventional device using a single light source (mercury lamp). can. In addition, the collimation half-width can be changed by arranging the unit irradiation unit, and it is possible to provide a lighting device that meets various needs.

Further, the plurality of rod lenses are held by the lens holding portion in a state of being separated from each other, and the plurality of rod lenses are fixed to the lens holding portion by the lens fixing portion. Therefore, the assembly accuracy of the rod lens can be improved. Further, the position shift due to the disturbance such as vibration and temperature change is prevented, and the occurrence of light loss is suppressed.

As described above, according to the present invention, it is possible to stably illuminate the illuminating device while reducing the size of the illuminating device.

It is a figure which shows the 1st Embodiment of the lighting apparatus which concerns on this invention. It is a figure which shows the structure of the irradiation unit used in the lighting apparatus of FIG. It is a figure which shows the structure of the irradiation unit of FIG. It is a figure which shows the adjustment operation of the collimation half-width in the lighting apparatus of FIG. It is a figure which shows the 2nd Embodiment of the lighting apparatus which concerns on this invention. It is a figure which shows the 3rd Embodiment of the lighting apparatus which concerns on this invention. It is a figure which shows the 4th Embodiment of the lighting apparatus which concerns on this invention. It is a figure which shows the 5th Embodiment of the lighting apparatus which concerns on this invention. It is a figure which shows the 6th Embodiment of the lighting apparatus which concerns on this invention. It is a figure which shows the 7th Embodiment of the lighting apparatus which concerns on this invention. It is a figure which shows the 8th Embodiment of the lighting apparatus which concerns on this invention.

FIG. 1 is a diagram showing a first embodiment of a lighting device according to the present invention. Further, FIG. 2 is a diagram showing a configuration of an irradiation unit used in the lighting device of FIG. Further, FIG. 3 is a perspective view showing the configurations of the light source unit and the tapered rod lens unit used in the irradiation unit of FIG. 2. The lighting device 100 includes an LED irradiation unit 1 that irradiates a plurality of lights, a collimation mirror 2, and a controller 3 that controls LED lighting in the LED irradiation unit 1. The irradiation surface is generated by LED lighting by the controller 3. (Exposure surface) It has a function of uniformly illuminating S.

The LED irradiation unit 1 includes a plurality of light source units 10 having a plurality of (49 in this embodiment) ultraviolet LEDs 11 (hereinafter simply referred to as “LED 11”) and a plurality of (49 in this embodiment) tapered rod lenses 121. It includes a taper rod lens unit 12 held by a lens holding unit 123, an incident side fly eye lens 13, and an outgoing side fly eye lens 14. Although not shown, in the light source unit 10, the LEDs 11 are arranged in a 7 × 7 two-dimensional matrix on one main surface of the flat plate-shaped substrate 111 (note that in FIG. 2, one LED row (Note that in FIG. 2) Or the LED line) is shown). Each LED 11 is electrically connected to the controller 3, and can be turned on and off independently in response to a command from the LED lighting control unit 31 of the controller 3. As for which LED 11 is to be turned on, information given to the LED lighting control unit 31 from the lighting condition setting unit 32 of the controller 3 according to the lighting conditions such as the collimation half-width and the illuminance on the irradiation surface S will be described later. Determined by.

Further, in the taper rod lens unit 12, 49 taper rod lenses 121 have a 7 × 7 two-dimensional matrix like the LED 11, and each has a one-to-one correspondence with the LED 11. Is arranged. More specifically, each tapered rod lens 121 has a tapered shape in which the cross-sectional area increases from the incident surface 121a to the exit surface 121b. Then, as shown in FIG. 2, the taper rod lens 121 is arranged so that the incident surface 121a of the taper rod lens 121 faces the light emitting surface 11a of the LED 11 for each LED 11 and is in contact with the emitting surface of the LED 11. There is.

Here, if the taper rod lens 121 deviates from the design position, light loss occurs between the LED 11 and the incident surface 121a of the taper rod lens 121, and between the exit surface 121b of the taper rod lens 121 and the lens element 131. .. Therefore, in this embodiment. For example, as shown in FIG. 3, seven tapered rod lenses 121 are designated as one rod lens group 122, and the tapered rod lens 121 is integrally held by the lens holding portion 123 for each rod lens group 122.

The lens holding portion 123 is composed of a strip-shaped metal plate 123a as shown in the broken line region in FIG. The metal plate 123a is provided with a plurality of (7 in this embodiment) through holes 123b at the same pitch as the arrangement pitch of the taper rod lens 121. Of both main surfaces of the metal plate 123a, the opening of the through hole 123b on the incident side main surface 123c on the side facing the LED 11 (right hand side in the figure) is also on the side facing the collimation mirror 2 (left hand side in the figure). The opening of the through hole 123b in the main surface 123d on the exit side also has the same shape and size as the exit surface 121b of the taper rod lens 121. Therefore, when the end portion of the taper rod lens 121 on the exit surface 121b side, that is, the anti-LED side end portion 121d is fitted into the through hole 123b, the plurality of taper rod lenses 121 are separated from each other and the taper rod lens 121. The lens holding portion 123 holds the metal plate 123a in a state where the emitting surface 121b is flush with the emitting side main surface 123d of the metal plate 123a. On the other hand, on the incident side main surface 123c of the metal plate 123a, the taper rod lens 121 is in a loosely inserted state, and a gap region is formed. In the present embodiment, the gap region is filled with the adhesive 124, and the taper rod lens 121 is firmly fixed to the metal plate 123a. As described above, in the present embodiment, the adhesive 124 functions as the "lens fixing portion" of the present invention. In the broken line region of FIG. 3, dots are added to schematically show the adhesive 124 that has entered the inside of the gap region.

Further, in the present embodiment, in order to smoothly and evenly fill the gap region with the adhesive 124, the lens holding portion 123 includes a region of the inner wall of the through hole 123b corresponding to the ridge line 121c of the tapered rod lens 121. A groove portion 123e is provided in the groove portion 123e. As a result, the adhesive 124 injected from the outside spreads over the entire gap region through the groove portion 123e to obtain a relatively large joint area, and the fixing strength can be increased. It should be noted that providing the groove portion 123e is not an essential requirement for fixing with the adhesive 124, and for example, as shown in FIG. 5 described later, the adhesive 124 is filled in the gap region without providing the groove portion 123e. It may be configured.

As described above, in the present embodiment, the anti-LED side end portion 121d (left hand side end portion in FIG. 3) of the taper rod lens 121 is held by the lens holding portion 123 and fixed by the adhesive 124. Therefore, it is possible to improve the assembly accuracy of the taper rod lens unit 12 and effectively prevent the positional deviation due to disturbance such as vibration and temperature change, and it is possible to effectively suppress the occurrence of light loss. That is, in each LED 11, the emitted light of the LED 11 is efficiently incident on the taper rod lens 121 via the incident surface 121a. Further, the incident light travels to the exit surface 121b while being repeatedly reflected inside the taper rod lens 121 a plurality of times. Therefore, light with less uneven brightness is emitted from the exit surface 121b toward the incident side fly-eye lens 13.

The incident side fly-eye lens 13 has 49 lens elements 131. Like the LED 11 and the taper rod lens 121, these lens elements 131 have a 7 × 7 two-dimensional matrix, and are arranged in a one-to-one correspondence with the taper rod lens 121, respectively. More specifically, as shown in FIG. 2, the lens element 131 is arranged so as to be in contact with the exit surface 121b of the taper rod lens 121 for each taper rod lens 121. By contacting the lens element 131 with the exit surface 121b of the taper rod lens 121 in this way, light can be efficiently incident on the lens element 131 from the taper rod lens 121.

Further, in the present embodiment, the exit-side fly-eye lens 14 is arranged at a position away from the incident-side fly-eye lens 13 configured in this way on the anti-LED side (left-hand side in FIG. 2). The exit-side fly-eye lens 14 also has 49 lens elements 141 like the incident-side fly-eye lens 13. Then, as shown in FIG. 2, the lens element 141 is provided in a one-to-one correspondence with the lens element 131.

As described above, in the present embodiment, the light emitted from one LED 11 is irradiated to the collimation mirror 2 via the taper rod lens 121, the lens elements 131, and 141 corresponding to the LED 11. The LED 11, the tapered rod lens 121, the lens elements 131, and 141 constitute an optical element that irradiates the light emitted from the LED 11 toward the collimation mirror 2, that is, a unit irradiation unit 15 (see FIG. 2). That is, in the LED irradiation unit 1 of the present embodiment, 49 unit irradiation units 15 are provided in a 7 × 7 two-dimensional matrix. Then, when the LED 11 is turned on, light is irradiated to the collimation mirror 2 from each unit irradiation unit 15, and the collimation mirror 2 collimates and irradiates the irradiation surface S.

Further, in the present embodiment, by selecting the LED 11 to be turned on by the controller 3 as described above, it is possible to change the number and arrangement of the unit irradiation units 15 that irradiate the collimation mirror 2 with light. , This makes it possible to change the half-width collimation. This point will be described in detail with reference to FIG.

FIG. 4 is a diagram showing a collimation half-width adjustment operation in the lighting device of FIG. The figure shown in the right column of the figure is a schematic view when the LED irradiation unit 1 is viewed from the collimation mirror 2 side, and among the lens elements 141 with hatching, the LED 11 corresponding to the lens element 141 is turned off. In other words, it indicates that the corresponding LED 11 is lit. That is, the figure (a) shows the time when all the LEDs 11 are turned on, and the figure (b) shows the time when the LED 11 of the center 5 × 5 is turned on.

In the left column of FIG. 4, a part of the light beam emitted to the irradiation surface S is shown by a two-dot chain line, and as is clear from these, the LED 11 is fully lit (7 × 7) to partially lit (5). By changing to × 5), the collimation half-width becomes smaller from the collimation half-width (θa / 2) to the collimation half-width (θb / 2). Further, although the illustration in FIG. 4 is omitted, if only the central 3 × 3 LED 11 is turned on, the half-width collimation can be further reduced. The collimation half-width can be changed by arranging the LED 11 (unit irradiation unit 15) that is lit in this way. Further, although only the half-width collimation is shown in FIG. 4, the illuminance and the illuminance distribution on the irradiation surface S can also be changed by the lighting / extinguishing control of the LED 11.

As described above, in the present embodiment, a plurality of unit irradiation units 15 are arranged two-dimensionally to illuminate the irradiation surface S. Therefore, the lighting device 100 can be downsized as compared with the conventional device using a single light source (mercury lamp). Further, by controlling the lighting / extinguishing of the LED 11 independently, it is possible to change and control the half-width collimation, the illuminance, and the illuminance distribution, and it is possible to perform lighting according to various needs.

Further, as described above, the lens holding portion 123 is provided with a rectangular through hole 123b, and the anti-LED side end portion 121d of the taper rod lens 121 is fitted into each through hole 123b and held by the lens holding portion 123, and the adhesive 124 is used. It is fixed. Therefore, the occurrence of the above-mentioned light loss can be effectively suppressed by improving the assembly accuracy of the taper rod lens unit 12 and preventing the positional deviation due to disturbances such as vibration and temperature change. Further, in the above embodiment, since the entrance surface 121a and the exit surface 121b of the taper rod lens 121 are in contact with the LED 11 and the lens element 131, respectively, the contact surface may be scratched due to the misalignment due to disturbance. However, in the present embodiment, as described above, it is possible to effectively prevent the contact surface from being scratched by the effect of preventing the position shift by the lens holding portion 123.

As described above, in the first embodiment, the LED 11 corresponds to an example of the "light emitting element" of the present invention. Further, the collimation mirror 2 corresponds to an example of the "collimation optical system" of the present invention. Further, the metal plate 123a corresponds to an example of the "flat plate member" of the present invention.

The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit of the present invention. For example, in the first embodiment, the openings of the through holes 123b in the incident side main surface 123c and the exit side main surface 123d both have the same shape and the same size, but they may be different from each other. For example, as shown in FIG. 5, the opening of the through hole 123b on the exit side main surface 123d has the same shape and size as the exit surface 121b of the taper rod lens 121, while the opening of the through hole 123b on the entrance side main surface 123c is made. It may be expanded beyond that (second embodiment). In this case, the through hole 123b has a reverse taper shape in which the cross-sectional area decreases from the entrance surface 121a to the exit surface 121b, the degree of clearance of the taper rod lens 121 on the entrance side main surface 123c is large, and the gap region Is spreading. Therefore, the adhesive 124 can be satisfactorily filled in the entire gap region without providing the groove portion 123e.

Further, in the first embodiment and the second embodiment, the adhesive 124 functions as the "lens fixing portion" of the present invention, but other methods, for example, the mechanical lens shown in FIGS. 6 to 9. The taper rod lens 121 may be fixed to the lens holding portion 123 by the fixing portion (third embodiment to the sixth embodiment).

As shown in FIG. 6, a taper rod lens fitted into the through hole 123b by providing a through hole 123f communicating with the through hole 123b in the metal plate 123a and mounting a ball plunger 125 in the through hole 123f. The anti-LED side end portion 121d of 121 may be pressed and fixed (third embodiment).

Further, as shown in FIG. 7, the shape of the through hole 123b is changed from rectangular to circular, and after the rod ring 126a is inserted into the through hole 123b, the through hole 123f and the through hole provided in the rod ring 126a are formed. By attaching the ball plunger 126b, the anti-LED side end 121d of the tapered rod lens 121 fitted in the rod ring 126a may be pressed and fixed (fourth embodiment). As described above, in the embodiment shown in FIG. 7, the lens fixing portion 126 is configured by the rod ring 126a and the ball plunger 126b.

Further, as shown in FIG. 8, a lens fixing portion 127 composed of a rod hold plate 127a may be used (fifth embodiment). The rod hold plate 127a is provided with a through hole 127b that can engage with the ridge line 121c of the tapered rod lens 121. The taper rod lens 121 can be fixed by mounting the rod hold plate 127a from the incident surface 121a side of the taper rod lens 121 and attaching it to the lens holding portion 123 with the cap screw 127c.

Further, as shown in FIG. 9, a lens including a rod lens holder 128b having a through hole 128a that allows the taper rod lens 121 to be freely inserted, two types of rod rings 128c and 128d, and a tin (Zn) plate 128e. A fixed portion 128 may be used (sixth embodiment). Here, the rod lens holder 128b is attached to the lens holding portion 123 by the cap screw 128f. Further, the taper rod lens 121 is inserted through the through hole 128a of the rod lens holder 128b, and the anti-LED side end portion 121d of the taper rod lens 121 is fitted into the through hole 123b. Further, the rod rings 128c and 128d are fitted onto the tapered rod lens 121, and the tin plate 128e is press-fitted between the tapered rod lens 121 and the rod rings 128c and 128d. Further, the rod rings 128c and 128d are fixed to the rod lens holder 128b by the set screw 128g. In this way, the tapered rod lens 121 is not only fitted and held in the lens holding portion 123, but also fixed to the rod lens holder 128b by the lens fixing portion 128.

Further, in the above embodiment, the collimation mirror 2 is used as the collimating optical system, but for example, as shown in FIG. 10, a collimation lens 4 may be used (7th embodiment), and illumination using the collimation lens 4 is used. The device 200 also has the same effects as the lighting device 100 according to the first to sixth embodiments.

Further, in the first embodiment, a fly-eye lens is used as the "lens array", but for example, as shown in FIG. 11, a drum lens array may be used as the "lens array" (eighth embodiment). That is, in the eighth embodiment, the LED irradiation unit 1 includes a taper rod lens unit 12 and 5 composed of a total of 25 LEDs 11 of 5 × 5 and a total of 25 taper rod lenses 121 of 5 × 5. It includes a drum lens array 16 composed of a total of 25 drum lenses 161 of × 5. The LED 11, the tapered rod lens 121, and the drum lens 161 are all arranged in a 5 × 5 two-dimensional matrix. Of these, the taper rod lens 121 is held by the lens holding portion 129 and fixed by an adhesive (not shown) as in the first embodiment and the second embodiment. Then, the light emitted from one LED 11 is irradiated to the collimating optical system such as the collimation mirror 2 and the collimation lens 4 via the taper rod lens 121 and the drum lens 161 corresponding to the LED 11. As described above, in the eighth embodiment, 25 unit irradiation units 15 (= LED 11 + taper rod lens 121 + drum lens 161) are provided in a 5 × 5 two-dimensional matrix. Then, when the LED 11 is turned on, light is irradiated to the collimating optical system from each unit irradiation unit 15, and the collimating optical system collimates and irradiates the irradiation surface S. In the eighth embodiment, the drum lens 161 corresponds to the "lens element". Further, as in the first to seventh embodiments, the plurality of tapered rod lenses 121 are divided into a plurality of rod lens groups 122, and the tapered rod lenses 121 are integrated by the lens holding portion 123 for each rod lens group 122. May be held in.

Further, in the first to seventh embodiments, the rod lens group 122 is divided into a plurality of rod lens groups 122, and the taper rod lens 121 is integrally held by the lens holding portion 123 for each rod lens group 122. 8 As in the embodiment, the all-tapered rod lens 121 may be integrally held by one lens holding portion.

Further, in the above embodiment, the collimation half-width can be changed by independently turning on / off each LED 11 by the controller 3, but controlling a plurality of LEDs 11 independently is not an essential requirement of the present invention. , Optional requirement. For example, when the specifications (including the half-width collimation) of the lighting devices 100 and 200 are predetermined, the number and arrangement of the unit irradiation units 15 may be set according to the half-width collimation. It is possible to provide a lighting device that meets the needs of the above.

Further, in the above embodiment, the ultraviolet LED 11 is used as the light emitting element, but the type of the light emitting element is not limited to this, and for example, an LED other than the ultraviolet light may be used as the light emitting element.

Further, in the above embodiment, the tapered rod lens 121 having a square pyramid shape is used as the "rod lens" of the present invention, but a rod lens having another shape may be used, for example, a polygonal pyramid shape or a truncated cone. A rod lens having a shape or the like may be used. Further, although the entrance surface 121a and the exit surface 121b of the taper rod lens 121 are in contact with the LED 11 and the lens element 131, respectively, it is not essential and optional. That is, a gap may be provided between the incident surface 121a of the tapered rod lens 121 and the LED 11 and / or between the emitting surface 121b of the tapered rod lens 121 and the lens element 131 to prevent scratches. However, in order to suppress light loss, it is desirable to make the size of the gap as small as possible, and as in the fourth embodiment and the fifth embodiment, the taper rod lens 121 is converted to the LED 11 by using the lens holding portion 123. And it is preferable to precisely position the lens element 131.

Further, in the above embodiment, the light emitting elements such as the LED 11 are arranged in a two-dimensional matrix, but the arrangement pattern of the light emitting elements is not limited to this and is arbitrary.

Further, the application target of the lighting device according to the present invention is not limited to the exposure device, but includes a lighting device for optical inspection and the like.

The present invention can be applied to a general lighting device that illuminates an irradiation surface using a plurality of light emitting elements.

1 ... LED irradiation unit 2 ... Collimation mirror (collimation optical system)
4 ... Collimation lens (collimation optical system)
11 ... LED (light emitting element)
12 ... Tapered rod lens unit 121 ... Tapered rod lens 121a ... Incident surface (of tapered rod lens) 121b ... Ejecting surface (of tapered rod lens) 123, 129 ... Lens holding part 124 ... Adhesive (lens fixing part)
125 ... Ball plunger (lens fixing part)
126, 127, 128 ... Lens fixing part

Claims (6)

A lighting device that irradiates the light emitted from the irradiation unit via the collimating optical system.
The irradiation unit
With multiple light emitting elements
For each of the light emitting elements, a plurality of rod lenses arranged so that the incident surface faces the light emitting element side and the exit surface faces the collimating optical system side.
A lens holding portion that holds the plurality of rod lenses in a state of being separated from each other,
A lens fixing portion for fixing the plurality of rod lenses to the lens holding portion is provided.
The rod lens has a polygonal frustum shape in which the cross-sectional area expands from the entrance surface to the exit surface.
The lens holding portion can be fitted with a flat plate member having an incident side main surface facing the light emitting element and an emitting side main surface facing the collimating optical system, and an end portion on the emitting surface side for each rod lens. It has a plurality of holding through holes provided and a groove portion provided in a region of the inner wall of the holding through hole corresponding to the ridgeline of the rod lens.
The lens fixing portion is an adhesive filled between the holding through hole and the side surface of the rod lens.
The end portion of the side surface of the rod lens on the exit surface side is supported by engaging with the lens holding portion and is fixed to the lens holding portion by the lens fixing portion. Lighting device. A lighting device that irradiates the light emitted from the irradiation unit via the collimating optical system.
The irradiation unit
With multiple light emitting elements
For each of the light emitting elements, a plurality of rod lenses arranged so that the incident surface faces the light emitting element side and the exit surface faces the collimating optical system side.
A lens holding portion that holds the plurality of rod lenses in a state of being separated from each other,
A lens fixing portion for fixing the plurality of rod lenses to the lens holding portion is provided.
The rod lens has a tapered shape in which the cross-sectional area expands from the entrance surface to the exit surface.
The lens holding portion can be fitted with a flat plate member having an incident side main surface facing the light emitting element and an emitting side main surface facing the collimating optical system, and an end portion on the emitting surface side for each rod lens. It has a plurality of holding through holes provided, and has a plurality of holding through holes.
The lens fixing portion is an adhesive filled between the holding through hole and the side surface of the rod lens.
In the lens holding portion, the inner wall of the holding through hole has a reverse taper shape in which the cross-sectional area decreases from the incident surface to the exit surface.
The end portion of the side surface of the rod lens on the exit surface side is supported by engaging with the lens holding portion and is fixed to the lens holding portion by the lens fixing portion. Lighting device. A lighting device that irradiates the light emitted from the irradiation unit via the collimating optical system.
The irradiation unit
With multiple light emitting elements
For each of the light emitting elements, a plurality of rod lenses arranged so that the incident surface faces the light emitting element side and the exit surface faces the collimating optical system side.
A lens holding portion that holds the plurality of rod lenses in a state of being separated from each other,
A lens fixing portion for fixing the plurality of rod lenses to the lens holding portion is provided.
The rod lens has a polygonal frustum shape in which the cross-sectional area expands from the entrance surface to the exit surface.
The lens holding portion can be fitted with a flat plate member having an incident side main surface facing the light emitting element and an emitting side main surface facing the collimating optical system, and an end portion on the emitting surface side for each rod lens. It has a plurality of holding through holes provided, and has a plurality of holding through holes.
The lens fixing portion has a rod hold plate provided with a fixing through hole that can be engaged with the ridge line of the rod lens for each rod lens, and the fixing through hole is made to correspond to the rod lens. While being attached to the lens holding portion from the incident surface, the rod holding plate whose ridge line engages with the inner peripheral surface of the fixing through hole is attached to and fixed to the lens holding portion.
A lighting device characterized by that. A lighting device that irradiates the light emitted from the irradiation unit via the collimating optical system.
The irradiation unit
With multiple light emitting elements
For each of the light emitting elements, a plurality of rod lenses arranged so that the incident surface faces the light emitting element side and the exit surface faces the collimating optical system side.
A lens holding portion that holds the plurality of rod lenses in a state of being separated from each other,
A lens fixing portion for fixing the plurality of rod lenses to the lens holding portion is provided.
The rod lens has a tapered shape in which the cross-sectional area expands from the entrance surface to the exit surface.
The lens holding portion can be fitted with a flat plate member having an incident side main surface facing the light emitting element and an emitting side main surface facing the collimating optical system, and an end portion on the emitting surface side for each rod lens. It has a plurality of holding through holes provided, and has a plurality of holding through holes.
The lens fixing portion has a rod lens holder provided with a play-insertion through hole for allowing the rod lens to be loosely inserted for each rod lens, and the play-insertion through hole is made to correspond to the rod lens. However, the rod lens holder attached to the lens holding portion is attached to the lens holding portion from the incident surface, and the rod lens is incident on the free insertion through hole provided in the rod lens holder for each rod lens. Fix the end on the face side
A lighting device characterized by that. The lighting device according to any one of claims 1 to 4.
The shape and size of the opening of the holding through hole before Symbol emission side main surface is the same as the shape and size of the exit surface of each of the rod lenses, and the exit side main surface to the exit surface of the rod lens A lighting device that keeps the lens matched. The lighting device according to any one of claims 1 to 5.
An illuminating device in which the rod lens can be freely inserted into the opening of the holding through hole on the main surface on the incident side.

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