JP2014194918A - Linear light irradiation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a linear light irradiation device which facilitates lens alignment and which can improve illuminance uniformity of line light.SOLUTION: A linear light irradiation device includes: a plurality of light sources which are linearly arrayed along one direction and which have optical axes parallel to one another; and a rod lens which has a lateral surface provided with a plane of incidence, into which light from the plurality of light sources is launched, and a light emission surface, from which the light is emitted, and which has the plane of incidence and the light emission surface positioned on the same circumference. The two rod lenses are arrayed in parallel with each other with respect to a columnar direction.

Description

  The present invention relates to a line light irradiation apparatus.

  Conventionally, a plurality of light sources (for example, LEDs) are linearly arranged along one direction, and rod lenses are arranged in the light emission direction of these light sources, and light from each light source is made elliptical by the rod lenses. There has been known a light irradiation apparatus that forms line-shaped light (hereinafter also referred to as “line light”) by condensing and superimposing them (see, for example, Patent Documents 1 and 2).

International Publication No. 2010/125836 JP 2012-186014 A

  In the light irradiation apparatus of Patent Document 1, a plano-convex cylindrical lens is used as a rod lens. Further, in order to form long line light, a plurality of plano-convex lenses are arranged side by side in the columnar direction of the rod lens. At this time, if the directions of the plane portions of the plurality of plano-convex lenses are not aligned, the light condensing position is shifted by each plano-convex lens. For this reason, the light irradiation apparatus of Patent Document 1 requires a rod lens arrangement accuracy, and there is a problem that a slight inclination of the lens or the like causes a deviation of the irradiation position, so that accurate irradiation cannot be performed.

  In the light irradiation apparatus of Patent Document 2, a rod lens having a circular cross section (hereinafter also referred to as “round rod lens”) is used as the rod lens. When a round rod lens is used as the rod lens, the diameter of the lens cannot be increased due to restrictions on the size of the device. However, when a round rod lens with a small diameter is used, the round rod lens with a small diameter has a large curvature, and thus the distance from the light source to the irradiation surface (focal length) becomes short. Therefore, the light reaches the irradiation surface before the light from each light source sufficiently overlaps. As a result, there is a problem that the illuminance increases near the optical axis from the light source in the line light, while the illuminance decreases between the light source and the light source, and the illuminance uniformity of the line light decreases.

  In view of the above-described points, the present invention is to provide a line-shaped light irradiation device that can easily align a lens and can improve the illuminance uniformity of line light.

The line-shaped light irradiation apparatus of the present invention is
A plurality of light sources arranged linearly along one direction and having optical axes parallel to each other;
A light incident surface on which light from the plurality of light sources is incident and a light exit surface from which the light is emitted; and a rod lens having the incident surface and the light exit surface on the same circumference;
There are two rod lenses, which are arranged parallel to each other in the columnar direction.

  According to the above configuration, the rod lens has an incident surface on which light from a plurality of light sources is incident and an exit surface from which the light is emitted on the side surface, and the incident surface and the exit surface are on the same circumference. . Since the displacement of the rod lens in the circumferential direction does not affect the accuracy of light collection, the positioning accuracy of the rod lens in the circumferential direction is not required. As a result, the rod lens can be easily aligned.

  Further, there are two rod lenses, which are arranged parallel to each other in the columnar direction. Therefore, even if the curvature of the entrance surface and the exit surface of each rod lens is large (for example, even when a round rod lens having a small diameter is used), the separation distance between the two rod lenses and the curvature of each rod lens By appropriately setting the combination, it is possible to increase the distance from the light source to the irradiation surface. As a result, the light from each light source can be sufficiently expanded in the columnar direction of the rod lens and superimposed, and the illuminance uniformity of the line light can be improved.

  As described above, according to the above configuration, two rod lenses in which the incident surface on which light from a plurality of light sources is incident and the emission surface from which the light is emitted are on the same circumference are used, and these are arranged in a columnar direction. Since they are arranged in parallel to each other, it is easy to align the lens, and it is possible to improve the illuminance uniformity of the line light.

  The said structure WHEREIN: The bottom surface of the said rod lens may have a light reflection function.

  Thereby, the light spread in the bottom surface direction can be returned to the center side of the rod lens, and a decrease in the light amount at both ends of the line light can be suppressed.

  In the above configuration, a reflector may be provided between the bottom surfaces on the same side of the two rod lenses.

  Thereby, the light which spread to the portion between the bottom surfaces on the same side of the two rod lenses can be returned, and the decrease in the light amount at both ends of the line light can be further suppressed.

In the above configuration, it has a holding mechanism for holding the rod lens,
The holding mechanism may be a cantilever structure having a holding portion for holding the rod lens and a bar portion capable of forming a deflection.

  Thereby, the rod lens clamped by the clamping part is aligned by the deflection of the bar part. As a result, lens alignment becomes easier.

  According to the line-shaped light irradiation device of the present invention, it is easy to align the lens, and it is possible to improve the illuminance uniformity of the line light.

It is a perspective view showing typically a line light irradiation device concerning one embodiment of the present invention. (A) is the left view of the linear light irradiation apparatus shown in FIG. 1, (b) is the front view. It is a perspective view which shows the state which removed the outer cover of the linear light irradiation apparatus shown in FIG. (A) is the left view of the linear light irradiation apparatus shown in FIG. 3, (b) is the front view. It is the sectional view on the AA line of the linear light irradiation apparatus shown in FIG.4 (b). It is a front view center longitudinal cross-sectional view of the linear light irradiation apparatus shown in FIG.4 (b). (A) And (b) is a schematic diagram for demonstrating the line light radiate | emitted from the linear light irradiation apparatus shown in FIG. (A) And (b) is a schematic diagram for demonstrating the line light radiate | emitted from the linear light irradiation apparatus which concerns on other embodiment. It is a schematic diagram for demonstrating one usage example of a line-shaped light irradiation apparatus. It is a side view longitudinal cross-sectional view of the linear light irradiation apparatus which concerns on other embodiment. It is a front view center longitudinal cross-sectional view of the linear light irradiation apparatus shown in FIG.

  A line light irradiation apparatus according to an embodiment of the present invention will be described with reference to the drawings. In each figure, the dimensional ratio in the drawing does not necessarily match the actual dimensional ratio.

  FIG. 1 is a perspective view schematically showing a line light irradiation apparatus according to an embodiment of the present invention, FIG. 2 (a) is a left side view thereof, and FIG. 2 (b) is a front view thereof. FIG.

  The line light irradiation apparatus 10 includes a main body 12 and an outer cover 14 that covers a side surface of the main body 12. The outer cover 14 includes a cover 14 a that covers the left and right side surfaces of the main body 12 and a cover 14 b that covers the front and back surfaces. The cover 14 a is screwed to the left and right of the main body 12 in a manner that does not cover the side surface of the heat sink 20. The cover 14a and the cover 14b are formed of a plate-like metal, and the main body 12 side of the cover 14a is mirror-finished on the entire surface.

  The second rod lens 28 is exposed on the upper side of the line light irradiation device 10, and the line light formed by the main body 12 is emitted from the second rod lens 28. Further, the heat sink 20 is exposed on the lower surface of the line light irradiation device 10.

  3 is a perspective view showing a state in which the outer cover of the linear light irradiation device shown in FIG. 1 is removed, FIG. 4 (a) is a left side view thereof, and FIG. It is a front view. FIG. 5 is a cross-sectional view taken along line AA of the linear light irradiation apparatus shown in FIG. 4B, and FIG. 6 is a front longitudinal sectional view of the center.

  The main body 12 includes a water-cooling heat sink 20 having a cooling water channel, an LED substrate 22 in which a plurality of LEDs 21 are linearly arranged along one direction, and a first light that condenses light from the plurality of LEDs 21 in a line shape. 1 rod lens 24 and second rod lens 28. In this embodiment, the case where the heat sink is a water cooling method will be described. However, the heat sink is not limited to the water cooling method, and may be an air cooling heat sink including fins, for example. In this case, a forced air cooling heat sink using a fan as well as natural air cooling may be used.

  The LED substrate 22 has a rectangular shape in plan view, and is disposed on the heat sink 20 such that the long side is parallel to the long side direction of the heat sink 20. On the LED substrate 22, a plurality of LEDs 21 are arranged at regular intervals in the long side direction. Each LED 21 is arranged so that its optical axes are parallel to each other. LED21 is comprised from the LED element 21a which is a light-emitting body, and the plano-convex lens 21b provided in the upper surface of the LED element 21a (refer FIG. 6).

  The LED element 21 a can be appropriately selected according to the wavelength of light desired to be emitted from the line light irradiation device 10. For example, when ultraviolet light is emitted from the line light irradiation device 10, an element that emits ultraviolet light may be employed as the LED element 21a.

  In the present embodiment, the plano-convex lens 21b is a condensing lens that can suppress the spread of light emitted from each LED element 21a to some extent. Accordingly, light emitted from a light source such as an LED can be efficiently guided to the incident surface 24b (see FIG. 5) of the first rod lens 24. A collimating lens may be used as the plano-convex lens 21b.

  Further, a protection member 23 for protecting the substrate 23 is provided on the upper side of the LED substrate 22. The protection member 23 is a metal member having a rectangular shape in a plan view and a U-shaped cross section, and is disposed on the LED substrate 22 with an open surface as a lower surface. A plurality of through holes 23a (see FIG. 3) corresponding to the distances between the LEDs 21 are formed on the upper surface of the protection member 23, and light from each LED 21 passes through each through hole 23a.

  The first rod lens 24 is a circular condensing lens (round bar lens) having the same length as the long side of the LED substrate 22. The first rod lens 24 is disposed on the LED substrate 22 so that the optical axis C1 (see FIG. 5) of the plurality of LEDs 21 and the optical axis C2 (see FIG. 5) of the first rod lens 24 coincide. Has been. Since the first rod lens 24 has a circular cross section, the incident surface 24b (see FIG. 5) on which the light from the LED 21 enters and the exit surface 24c (see FIG. 5) from which the light exits are the same. Formed on the circumference.

  The first rod lens 24 is held by a holding mechanism 25. The holding mechanism 25 has a cantilever structure including a pair of cantilevers 26 (cantilever 26-1 and cantilever 26-2) formed of the same material (see FIG. 5).

  The cantilever 26 includes a clamping part 26a (clamping parts 26a-1, 26a-2) and a bar part 26b (bar parts 26b-1, 26b-2) extending from the clamping part 26a and capable of forming a deflection. Have. The material of the cantilever 26 is not particularly limited as long as it can bend and generate stress, and various metals can be used.

  The cantilever 26 is screwed to the heat sink 20 on the opposite side of the bar portion 26b from the clamping portion 26a. The holding mechanism 25 sandwiches the first rod lens 24 from both sides (left and right sides in FIG. 5) by two cantilevers 26. Specifically, the sandwiching portion 26a has a curved surface 27 (curved surfaces 27-1 and 27-2) having a curvature slightly smaller than the curvature of the first rod lens 24 on the inner side, and the bar portion 26b is a heat sink. When the first rod lens 24 is disposed between the sandwiching portion 26a-1 and the sandwiching portion 26a-2 in the state of being fixed to 20, the bar portion 26b-1 and the bar portion 26b-2 are bent to the same extent. In this state, the first rod lens 24 is sandwiched between the sandwiching portion 26a-1 and the sandwiching portion 26a-2. Since the cantilever 26 is formed of the same material, the amount of deflection of the bar portion 26b is approximately the same. Therefore, the first rod lens 24 is aligned so as to be disposed immediately above the LED 21. At this time, since the curvature of the curved surface 27 of the sandwiching portion 26a is slightly smaller than the curvature of the first rod lens 24, the side surface of the first rod lens 24 is provided in the center of the curved surface 27 in the cylindrical direction. It is pinched | interposed between the clamping part 26a-1 and the clamping part 26a-2 in the state fitted in the groove | channel. Accordingly, the first rod lens 24 is positioned and held in the height direction. The first rod lens 24 has a circular cross section. Therefore, the deviation in the circumferential direction does not affect the accuracy of light collection. Therefore, the positioning accuracy in the circumferential direction of the first rod lens 24 is not required. As a result, the first rod lens 24 can be easily aligned.

  In the first rod lens 24, both bottom surfaces 24a are transparent by baking finish or the like. Thereby, the light spread in the direction of the bottom surface 24a can be transmitted or totally reflected. Here, the main body 12 side of the cover 14a is mirror-finished. Therefore, the light transmitted through the bottom surface 24a is reflected. As a result, all the light spread in the direction of the bottom surface 24a can be returned. Thereby, the fall of the light quantity of the both ends of line light can be suppressed. In addition, you may affix a mirror on the transparent both bottom surfaces 24a using the transparent adhesive transparent with respect to the light from a light source.

  The second rod lens 28 is a condensing lens (round bar lens) having a circular cross section having the same length as the long side of the LED substrate 22. The second rod lens 28 is parallel to the first rod lens 24 and the columnar direction, and the optical axis C2 of the first rod lens and the optical axis C3 of the second rod lens 28 (see FIG. 5). Are provided on the upper portion of the first rod lens 24 so as to match. Since the second rod lens 28 has a circular cross section, the incident surface 28b on which the light from the LED 21 is incident and the emission surface 28c on which the light is emitted are arranged on the same circumference.

  Similar to the first rod lens 24, the second rod lens 28 is held by a holding mechanism 30. The holding mechanism 30 has a cantilever structure including a pair of cantilevers 31 (cantilever 31-1 and cantilever 31-2) formed of the same material (see FIG. 4A).

  The cantilever 31 includes a clamping part 31a (clamping parts 31a-1, 31a-2) and a bar part 31b (bar parts 31b-1, 31b-2) extending from the clamping part 31a and capable of forming a deflection. Have. The material of the cantilever 31 is not particularly limited as long as it can bend and generate stress, and various metals can be used.

  The cantilever 31 is screwed to the heat sink 20 on the opposite side of the bar portion 31b from the clamping portion 31a. The holding mechanism 30 clamps the second rod lens 28 from both sides (left and right sides in FIG. 4A) by two cantilevers 31. Specifically, the sandwiching portion 31a has a curved surface 32 (curved surfaces 32-1 and 32-2) having a curvature slightly smaller than the curvature of the second rod lens 28 inside, and the bar portion 31b is a heat sink. When the second rod lens 28 is disposed between the sandwiching portion 31a-1 and the sandwiching portion 31a-2 in the state of being fixed to 20, the bar portion 31b-1 and the bar portion 31b-2 are bent to the same extent. In this state, the second rod lens 28 is sandwiched between the sandwiching portion 31a-1 and the sandwiching portion 31a-2. Since the cantilever 31 is formed of the same material, the amount of deflection of the bar portion 31b is approximately the same. For this reason, the second rod lens 28 is aligned so as to be disposed immediately above the first rod lens 24. At this time, since the curvature of the curved surface 32 of the sandwiching portion 31a is slightly smaller than the curvature of the second rod lens 28, the side surface of the second rod lens 28 is provided in the center of the curved surface 31 in the cylindrical direction. It is clamped between the clamping part 31a-1 and the clamping part 31a-2 in a state of being fitted in the groove 33. Therefore, the second rod lens 28 is positioned in the height direction and can be reliably fixed. The second rod lens 28 has a circular cross section. Therefore, the deviation in the circumferential direction does not affect the accuracy of light collection. Therefore, the positioning accuracy in the circumferential direction of the second rod lens 28 is not required. As a result, the second rod lens 28 can be easily aligned.

  In the second rod lens 28, both bottom surfaces 28a are transparent by baking finish or the like. Thereby, the light spread in the direction of the bottom surface 28a can be transmitted or totally reflected. Here, the main body 12 side of the cover 14a is mirror-finished. Accordingly, the light transmitted through the bottom surface 28a is reflected. As a result, all the light spread in the direction of the bottom surface 28a can be returned. Thereby, the fall of the light quantity of the both ends of line light can be suppressed. In addition, you may stick a mirror to the transparent both bottom surfaces 28a using the transparent adhesive transparent with respect to the light from a light source.

  The configuration of the line light irradiation apparatus 10 has been described above.

  Next, the irradiation mode of the line light emitted from the line light irradiation device 10 will be described. FIG. 7A and FIG. 7B are schematic views for explaining line light emitted from the line-shaped light irradiation device shown in FIG. In FIG. 7A and FIG. 7B, in order to explain the irradiation mode of the line light emitted from the line light irradiation device 10, the LED 21, the first rod lens 24, the second rod lens 28, And the outer cover 14 is shown in figure and the part which is not required for description is abbreviate | omitted. In FIG. 7A, a plurality of LEDs 21 are arranged in the vertical direction in the drawing, and the first rod lens 24 and the second rod lens 28 are arranged with the vertical direction in the drawing as a columnar direction. In FIG. 7B, a plurality of LEDs 21 are arranged in the frontward direction in the drawing, and the first rod lens 24 and the second rod lens 28 are columnar in the frontward direction in the drawing. It shows how they are arranged.

  As shown in FIG. 7B, the light emitted from the LED element 21a has a certain extent. The plano-convex lens 21b as a collimating lens makes the light emitted from the LED element 21a parallel light. The light emitted from the plano-convex lens 21 b enters the first rod lens 24. In the first rod lens 24, the light spreads in the columnar direction of the first rod lens 24. Therefore, the light from each LED 21 travels in the direction of the second rod lens 28 while overlapping in the columnar direction of the first rod lens 24. The second rod lens 28 is disposed at a position where almost all the light from the first rod lens 24 can be incident and the light can be collected. In FIG. 7B, the focal point of the first rod lens 24 is between the first rod lens 24 and the second rod lens 28, but the light emitted from the first rod lens 24 is The light is condensed and emitted again by the second rod lens 28. Thereby, the line light 34 can be irradiated to the focal position (irradiation surface) of the second rod lens 28.

  Thus, since the line-shaped light irradiation apparatus 10 uses two rod lenses, the distance from the LED 21 to the irradiation surface is higher than when only one rod lens (for example, only the first rod lens 24) is used. The distance can be increased. As a result, it is possible to sufficiently spread the light from each LED 21 in the columnar direction of the rod lens and to sufficiently overlap them, and to improve the illuminance uniformity of the line light 34.

  Here, when the distance between the centers of the LEDs 21 is d1, the LEDs 21 are arranged such that the distance d2 between the LED 21 located at the end of the plurality of LEDs 21 and the cover 14a is ½ of the distance d1. Yes. Since the distance d2 is ½ of the distance d1, the cover 14a that has been subjected to the mirror finish process is projected so that the plurality of LEDs 21 are present on the surface of the cover 14a. As a result, light is reflected as if light is emitted from the projected LED. Thereby, the fall of the light quantity of the both ends of the line light 34 can further be suppressed.

In the line light irradiation device 10, the entire surface of the main body 12 side of the cover 14a is mirror-finished. Therefore, it is possible to return the light that has spread to the portion 14c (see FIG. 2A) between the bottom surface 24a of the first rod lens 24 and the bottom surface 28a of the second rod lens 28 on the same side. It is possible to further suppress a decrease in the amount of light at both ends. In this embodiment, the case where the entire surface of the cover 14a is mirror-finished, that is, the case where the cover 14a itself corresponds to the reflector of the present invention has been described, but the present invention is not limited to this example. Alternatively, a reflecting plate such as a mirror may be disposed separately from the cover 14a.
In the present embodiment, the case where the entire surface of the cover 14a is mirror-finished has been described. However, in the present invention, the entire surface of the cover 14a may not be mirror-finished. For example, a reflecting plate may be provided only in a portion between the bottom surfaces on the same side of the two rod lenses. Even with such a configuration, the expanded light can be returned to the portion between the bottom surfaces on the same side of the two rod lenses, and the decrease in the light amount at both ends of the line light can be further suppressed. Because you can.

  In the embodiment described above, the case where the diameter of the first rod lens 24 is smaller than the diameter of the second rod lens 28 has been described. However, in the present invention, the relationship between the diameters of the two rod lenses is not limited to this example. That is, in the present invention, the distance from the light source to the irradiation surface can be set by appropriately selecting a combination of the separation distance between the two rod lenses and the curvature of each rod lens.

  FIG. 8A and FIG. 8B are schematic views for explaining line light emitted from a line light irradiation apparatus according to another embodiment. The example shown in FIGS. 8A and 8B is different in that the diameters of the first rod lens and the second rod lens are the same, and the line-shaped light irradiation device 10 is different in other points. Common. Therefore, a description will be given with the same reference numerals as those of the line light irradiation device 10 except for the first rod lens and the second rod lens.

  8A and 8B, in order to explain the irradiation mode of the line light emitted from the line light irradiation device according to another embodiment, the LED 21, the first rod lens 40, the second Only the rod lens 42 and the cover 14a are shown. As shown in FIG. 8B, the light emitted from the LED element 21a has a certain extent. The plano-convex lens 21b limits the spread of light emitted from the LED element 21a. The light emitted from the plano-convex lens 21 b enters the first rod lens 40. In the first rod lens 40, the light spreads in the columnar direction of the first rod lens 40. Therefore, the light from each LED 21 travels in the direction of the second rod lens 42 while overlapping in the columnar direction of the first rod lens 40. In FIG. 8B, the light incident on the first rod lens 40 becomes substantially parallel light and travels in the direction of the second rod lens. Then, the light incident on the second rod lens 42 is condensed and emitted. Thereby, the line light 44 can be irradiated to the focal position (irradiation surface) of the second rod lens 42. In this example, since the light incident on the first rod lens 40 becomes substantially parallel light, the second rod lens 42 can be arranged so that the distance from the LED 21 to the irradiation surface becomes a desired distance. .

  Next, a usage example of the line light irradiation apparatus will be described. Below, the usage example which irradiates the ultraviolet-ray line light to the outer peripheral side surface of a liquid crystal display panel is demonstrated.

  FIG. 9 is a schematic plan view for explaining an example of use of the line light irradiation device. The liquid crystal display panel 50 is formed by laminating various members such as a light guide plate, a polarizing plate, a liquid crystal panel, and a color filter with a transparent ultraviolet curable adhesive. The liquid crystal display panel 50 may further include a touch panel. In the manufacturing process of the liquid crystal display panel 50, a liquid ultraviolet curable adhesive is applied on one member or a sheet-like ultraviolet curable resin adhesive is disposed, and another member is placed thereon. After that, bonding is performed by irradiating ultraviolet rays from above. However, the adhesive often oozes out at the outer periphery of the bonding. Since such an exuded adhesive adheres to the outer peripheral portion of the laminate, it cannot be cured efficiently by ultraviolet irradiation from above. In particular, when the member to be laminated has a frame 51 that does not transmit ultraviolet rays, the outer peripheral portion cannot be irradiated with ultraviolet rays. Therefore, after laminating various members in the surface direction and irradiating ultraviolet rays from above, it is necessary to irradiate the outer peripheral portion with ultraviolet rays from the side surface direction.

  As shown in FIG. 9, one line-shaped light irradiation device 10 is arranged for each side surface so as to surround a position 52 where the liquid crystal display panel 50 is arranged. The line light emitted from the line-shaped light irradiation device 10 is longer than the necessary length of the line light (in the example of FIG. 9, the length of one side of the liquid crystal display panel 50) because the illuminance decreases at both ends. It is necessary to irradiate line light. For this reason, when the distance d3 to the irradiation surface is short, there is a possibility that the adjacent line-shaped light irradiation devices 10 may not be disposed due to contact with each other at the corner portion 55. However, in the line light irradiation apparatus 10, the distance to the irradiation surface can be increased by adjusting the diameters and the separation distances of the two rod lenses. As a result, it becomes possible to prevent the adjacent line light irradiation devices 10 from being in contact with each other and being unable to be arranged.

  In the above-described embodiment, the case where the light source of the present invention is an LED has been described. However, the light source in the present invention is not limited to this example, and may be, for example, an output end of an optical fiber.

  FIG. 10 is a side view longitudinal sectional view of a line light irradiation apparatus according to another embodiment, and FIG. 11 is a front view central longitudinal sectional view thereof. The linear light irradiation device 60 shown in FIG. 10 and FIG. 11 uses linear light irradiation in that an optical fiber is used as a light source, and the shape of the holding portion for holding the rod lens is a V-shaped groove without a curved surface. Unlike the device 10, it is common in other respects. Therefore, except for a different point, the same code | symbol as the linear light irradiation apparatus 10 is attached | subjected, and description of a common part shall be abbreviate | omitted. 10 and 11, the outer cover is not shown.

  The main body 62 condenses light from the water-cooling heat sink 20 provided with a cooling water channel, a plurality of optical fiber output ends 82 arranged linearly along one direction, and a plurality of optical fiber output ends 82 in a line. The first rod lens 24 and the second rod lens 28 are provided. The optical fiber output end 82 is an output end of the optical fiber 80, and light incident from an incident end (not shown) of the optical fiber 80 is output. In addition, since the light radiate | emitted from the optical fiber output end 82 is parallelized to some extent, it can be set as the structure which does not use the plano-convex lens 21b etc. as a condensing lens with which the linear light irradiation apparatus 10 is provided.

  Even in the line light irradiation device 60 according to the present embodiment, since two rod lenses are used as in the line light irradiation device 10, an optical fiber as a light source is used rather than a case where only one rod lens is used. The distance from the emission end 82 to the irradiation surface can be increased. As a result, the light from each optical fiber output end 82 can be sufficiently superimposed, and the illuminance uniformity of the line light can be improved.

  The first rod lens 24 is held by a holding mechanism 65. The holding mechanism 65 has a cantilever structure composed of a pair of cantilevers 66 (cantilever 66-1 and cantilever 66-2) formed of the same material (see FIG. 10).

  The cantilever 66 includes a sandwiching portion 66a (sandwich portions 66a-1 and 66a-2) and a bar portion 66b (bar portions 66b-1 and 66b-2) extending from the sandwiching portion 66a and capable of forming a deflection. Have. The material of the cantilever 66 is not particularly limited as long as it can bend and generate stress, and various metals can be used.

  The cantilever 66 is screwed to the heat sink 20 on the opposite side of the bar portion 66b from the clamping portion 66a. The holding mechanism 65 sandwiches the first rod lens 24 from both sides (left and right sides in FIG. 10) by two cantilevers 66. Specifically, the sandwiching portion 66 a has V grooves 67 (V grooves 67-1 and 67-2) on the inner side, and the first rod lens 24 is in a state where the bar portion 66 b is fixed to the heat sink 20. Is disposed between the sandwiching portion 66a-1 and the sandwiching portion 66a-2, the bar portion 66b-1 and the bar portion 66b-2 are bent to the same extent, and the first rod lens 24 is sandwiched between the sandwiching portions 66a. -1 and the clamping part 66a-2. Since the cantilever 66 is formed of the same material, the amount of deflection of the bar portion 66b is approximately the same. Therefore, the first rod lens 24 is aligned so as to be disposed immediately above the optical fiber output end 82. Moreover, since the clamping part 66a has the V groove 67 (V groove 67-1, 67-2) inside, the 1st rod lens 24 is positioned and hold | maintained in a height direction.

  Similar to the first rod lens 24, the second rod lens 28 is held by a holding mechanism 70. The holding mechanism 70 has a cantilever structure including a pair of cantilevers 71 (cantilever 71-1 and cantilever 71-2) formed of the same material (see FIG. 10).

  The cantilever 71 includes a pinching portion 71a (pinching portions 71a-1 and 71a-2) and a bar portion 71b (bar portions 71b-1 and 71b-2) extending from the pinching portion 71a and capable of forming a deflection. Have. The material of the cantilever 71 is not particularly limited as long as it can bend and generate stress, and various metals can be used.

  The cantilever 71 is screwed to the heat sink 20 on the opposite side of the bar portion 71b from the clamping portion 71a. The holding mechanism 70 sandwiches the second rod lens 28 from both sides (left and right sides in FIG. 10) by two cantilevers 71. Specifically, the sandwiching portion 71 a has V grooves 72 (V grooves 72-1 and 72-2) on the inner side, and the second rod lens 28 in a state where the bar portion 71 b is fixed to the heat sink 20. Is disposed between the sandwiching part 71a-1 and the sandwiching part 71a-2, the bar part 71b-1 and the bar part 71b-2 are bent to the same extent, and the second rod lens 28 is sandwiched by the sandwiching part 71a. -1 and the clamping part 71a-2. Since the cantilever 71 is formed of the same material, the amount of deflection of the bar portion 71b is approximately the same. For this reason, the second rod lens 28 is aligned so as to be disposed immediately above the first rod lens 24. Moreover, since the clamping part 71a has the V-groove 72 (V-grooves 72-1, 72-2) on the inner side, the first rod lens 24 is positioned and held in the height direction.

  In the above-described embodiment, the case where the rod lens of the present invention is a round bar lens having a circular cross-sectional shape has been described. However, the rod lens of the present invention is not limited to this example, and the incident surface on which light from a plurality of light sources enters and the exit surface from which the light exits may be on the same circumference. As such a rod lens, there can be mentioned, for example, one in which two side surfaces of a round rod lens are chamfered to the extent that they do not cover the entrance surface and the exit surface.

  In the present invention, the holding mechanism for holding the rod lens preferably has a cantilever structure like the holding mechanism 25, the holding mechanism 30, the holding mechanism 65, and the holding mechanism 70. However, the holding mechanism in the present invention is not limited to this example as long as the rod lens can be held. For example, using a member consisting of a clamping part that clamps the rod lens and a bar part that extends from the clamping part and cannot bend, an elastic body such as rubber or foam is installed in the clamping part to hold the rod lens. It is good also as a holding mechanism to do.

  In the above-described embodiment, the case where the sandwiching portion has a curved surface inside and the case where the holding portion has a V groove without a curved surface have been described. However, the shape of the clamping part in the present invention is not limited to these examples as long as the rod lens can be clamped.

  In the above-described embodiments, the case where the lengths of the two rod lenses are the same has been described. However, the lengths may be different as long as they do not depart from the spirit of the present invention.

  In the embodiment described above, the case where two rod lenses are used has been described. However, one or more rod lenses may be used as long as they do not depart from the spirit of the present invention. That is, the present invention is characterized by using at least two rod lenses.

  In the above-described embodiment, the case where a plurality of light sources are arranged in a line in a straight line has been described. However, in the present invention, the arrangement of the plurality of light sources is not limited to this, and may be two or more rows, for example.

In the present invention,
A plurality of light sources arranged linearly along one direction and having optical axes parallel to each other;
A rod lens having a light incident surface on which light from the plurality of light sources is incident and a light exit surface from which the light is emitted;
A holding mechanism for holding the rod lens;
The holding mechanism includes a line-shaped light irradiation device having a cantilever structure having a holding portion for holding the rod lens and a bar portion capable of forming a deflection (hereinafter referred to as a line according to a second aspect of the present invention). Also called a light irradiation device).

  According to the line light irradiation apparatus according to the second aspect of the present invention, the rod lens sandwiched by the sandwiching portion is aligned by the deflection of the bar portion. As a result, lens alignment becomes easier. In the second aspect of the present invention, the number of rod lenses may be one or plural. This is because even when there is only one rod lens, the rod lens is suitably aligned by the holding mechanism, and the rod lens can be positioned directly above the light source.

  In the second aspect of the present invention, the rod lens may not have the entrance surface and the exit surface on the same circumference. An example of such a rod lens is a plano-convex lens. This is because even if the entrance surface and the exit surface are rod lenses that are not on the same circumference, the rod lens is suitably aligned by the holding mechanism, and the rod lens can be positioned directly above the light source. However, it is preferable to use a rod lens in which the entrance surface and the exit surface are on the same circumference in that the accuracy of positioning the rod lens in the circumferential direction is not required.

  The embodiment of the present invention has been described above, but the present invention is not limited to the above-described example, and it is possible to make design changes as appropriate within a range that satisfies the configuration of the present invention.

10, 60 Line-shaped light irradiation device 12, 62 Main body 14 Outer cover 14a Cover 14b Cover 20 Heat sink 21 LED
21a LED element 21b Plano-convex lens 22 LED substrate 24, 40 First rod lens 24a (on the first rod lens 24) bottom surface 24b entrance surface 24c exit surface 25, 30 holding mechanism 26 (26-1, 26-2), 31 (31-1, 31-2) Cantilever 26a (26a-1, 26a-2), 31a (31a-1, 31a-2) Nipping part 26b (26b-1, 26b-2), 31b (31b-1) 31b-2) Bar portion 27 (27-1, 27-2) Curved surface 32 (32-1, 32-2) (of pinching portion 26a) Curved surface 28, 42 (of pinching portion 31a) Second rod lens 28a Bottom surface 28b (of second rod lens 28) Incident surface 28c Emission surface 34 Line light 65, 70 Holding mechanism 66 (66-1, 66-2), 71 (71-1, 71-2) Cantilever 66a 66a-1, 66a-2), 71a (71a-1, 71a-2) Nipping part 66b (66b-1, 66b-2), 71b (71b-1, 71b-2) Bar part 67 (67-1, 67-2), 72 (72-1, 72-2) V-groove C1 Optical axis C2 of LED 21 Optical axis C3 of first rod lens 24 Optical axis of second rod lens 28

Claims (4)

A plurality of light sources arranged linearly along one direction and having optical axes parallel to each other;
A light incident surface on which light from the plurality of light sources is incident and a light exit surface from which the light is emitted; and a rod lens having the incident surface and the light exit surface on the same circumference;
There are two rod lenses, and they are arranged in parallel to each other in the columnar direction.   The line light irradiation apparatus according to claim 1, wherein a bottom surface of the rod lens has a light reflection function.   The line light irradiation apparatus according to claim 1, wherein a reflection plate is provided between the bottom surfaces on the same side of the two rod lenses. A holding mechanism for holding the rod lens;
The line according to any one of claims 1 to 3, wherein the holding mechanism includes a cantilever structure having a holding part that holds the rod lens and a bar part that can bend. Light irradiation device.

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