Linear light emitting apparatus

Abstract

In order to provide a linear light emitting device with which it is possible to easily and accurately position on and secure a lens to a casing, this linear light emitting device comprises a plurality of LEDs arranged along a prescribed direction, a lens body extending along the direction in which the plurality of LEDs are positioned and having a flat surface and a curved surface, a casing, and a securing mechanism for securing the lens body to the casing, wherein: the light from the LEDs is condensed by the lens body and is emitted as linear light. The linear light emitting device is configured such that: the lens body has a flat surface and a curved surface; the securing mechanism has a pressing member that is provided to allow back and forth movement in the direction facing the lens body as viewed from the arrangement direction and that advances toward the lens body and presses the lens body, and a first reference surface and a second reference surface that are formed on the inner wall of the casing so as to be positioned on the opposite side to the pressing member across the lens body as viewed from the arrangement direction; and the lens body is caused to contact the first reference surface and the second reference surface by due to the pressing member pressing the lens body so as to secure the lens body.

Description

Line light emitting device

[0001] The present invention relates to a line light emitting device that irradiates an object (work) such as a product with line-shaped light in, for example, a factory or the like, and is preferably used for appearance inspection or the like.

[0002] Conventionally, as a line light emitting device, as shown in Patent Document 1, there is one including a plurality of LEDs arranged along a predetermined direction, a long rod lens extending along the arrangement direction thereof, a casing housing them, and fixing means for fixing the rod lens to the casing.

[0003] The fixing means of Patent Document 1 has four fixing members facing each other in two directions in order to position the long rod lens in two directions orthogonal to the long direction thereof.

[0004] JP-A-2023-130783

[0005] However, in the above line light emitting device, it is necessary to attach the fixing member to the inner wall of the casing before inserting the rod lens into the casing, which complicates the lens attachment work. There is also a problem that it is difficult to fix the lens accurately.

[0006] Therefore, the present invention has been made to solve the above problems, and the main object is to provide a line light emitting device that can easily and accurately position and fix a lens with respect to a casing.

[0007] In other words, the line light emission device according to the present invention comprises a plurality of LEDs arranged along a predetermined direction, a long lens body provided on the light emission side of the plurality of LEDs and extending along the arrangement direction of the plurality of LEDs, a casing housing the plurality of LEDs and the lens body, and a fixing mechanism for fixing the lens body to the casing, wherein the line light emission device focuses the light of the LEDs with the lens body and emits it as line light, the lens body having a flat surface and a curved surface, the fixing mechanism being provided so as to be able to move back and forth in the direction toward the lens body when viewed from the arrangement direction, and having a pressing member that moves toward the lens body and presses the lens body, and a first reference surface and a second reference surface formed on the inner wall of the casing so as to be on the opposite side of the pressing member with the lens body in between when viewed from the arrangement direction, and the fixing mechanism being configured such that the pressing member presses the lens body and the lens body comes into contact with both the first reference surface and the second reference surface and fixes the lens body.

[0008] With this configuration, the present invention allows the lens body to be fixed to the casing simply by advancing the pressing member in one direction after insertion, making the lens body fixing process far easier than in conventional methods. Furthermore, by using a configuration in which the flat surface of the lens body is pressed against a reference surface, the fixing mechanism can be simplified, reducing the number of required parts and contributing to cost reduction.

[0009] The fixing mechanism further has an inclined surface formed on at least one of the pressing surface of the pressing member or the pressed surface of the lens body, which is inclined with respect to the direction of travel of the pressing member. It is desirable that the pressing member presses the lens body via the inclined surface, thereby generating a force in the oblique direction relative to the direction of travel, and that this force causes the lens body to come into contact with both the first reference surface and the second reference surface. With this configuration, the force with which the pressing member presses the lens body is transmitted to the lens body as an oblique force via the inclined surface, and this oblique force can generate component forces toward the first reference surface and component forces toward the second reference surface, allowing the lens body to be pressed against these two surfaces simultaneously for accurate positioning.

[0010] Preferably, the inclined surface is a flat surface formed on the surface of the elongated lens body, extending from one end to the other in the direction of arrangement. With this configuration, since the inclined surface is uniformly formed along the direction of arrangement, it is less likely that the lens body will get caught on the inclined surface when inserted into the casing along this direction of arrangement.

[0011] It is desirable that the inclined surfaces are formed on both the pressing surface of the pressing member and the pressed surface of the lens body, and that these two inclined surfaces are inclined in the same direction. With this configuration, since the pressing surface and the pressed surface are inclined in the same direction, when the pressing member moves toward the lens body and these two surfaces come into contact, the surfaces slide against each other, allowing the lens body to move smoothly. In addition, the load on the lens body during pressing can be reduced, thereby preventing damage to the lens body.

[0012] Preferably, the first and second reference surfaces are perpendicular to each other, and the inclined surface is inclined at a 45-degree angle to both the first and second reference surfaces. With this configuration, the force pressing the lens body against the first and second reference surfaces can be made uniform.

[0013] Viewed from the arrangement direction, it is desirable that the direction of travel of the pressing member includes a directional component perpendicular to the direction of emission of the line light. More preferably, it is desirable that its direction of travel coincides with the direction perpendicular to the direction of emission of the line light. With this configuration, the pressing member travels from the side relative to the lens body, so interference with the optical path is less likely.

[0014] If the pressing members are to be continuously arranged along the direction of arrangement to match the elongated shape of the lens body, the pressing members themselves must also be elongated, making them difficult to handle during installation. Therefore, it is desirable that the pressing members be provided intermittently in multiple locations along the longitudinal direction. With this configuration, it is not necessary to match the shape of the elongated lens body to the pressing members, so the pressing members can be made into a form that is easy to handle. In addition, local distortion of the lens body can be corrected by individually adjusting the pressing force of each pressing member.

[0015] Preferably, the plurality of pressing members are provided intermittently along the entire length of the lens body in the longitudinal direction, and the first and second reference surfaces are provided continuously or intermittently along the entire length of the lens body in the longitudinal direction. With this configuration, distortion can be corrected along the entire length of the elongated lens body.

[0016] Preferably, the pressing member is a screw that engages with a screw hole formed in the casing. This configuration simplifies the fixing mechanism and makes it easy to fix the lens body. Furthermore, the degree of distortion correction can be easily adjusted by tightening or loosening the screw.

[0017] The screw has a conical tip, and it is desirable that the inclined surface of the tip presses against the lens body. With this configuration, a fixing mechanism can be realized inexpensively using existing positioning screws that have a tapered surface at the tip.

[0018] Preferably, the lens body is a cylindrical lens, and the fixing mechanism brings the flat surface into contact with either the first or second reference surface. With this configuration, simple and accurate positioning becomes possible by utilizing the flat surface of the cylindrical lens.

[0019] It is desirable that multiple cylindrical lenses be provided so that their optical axes align. With this configuration, aberrations can be reduced and illumination quality can be improved compared to creating line light using a rod lens. Furthermore, lens power can be ensured by using multiple lenses. However, when multiple lenses are used, high positioning precision is required to align the optical axes of each lens, and if the precision is poor, the illumination position will shift and the quality of illumination cannot be guaranteed. In response to this problem, the present invention, as described above, allows for high-precision positioning by utilizing the flat surface of the cylindrical lens, thereby improving the overall quality of illumination.

[0020] The casing extends along the longitudinal direction and has a pair of side walls that face each other, sandwiching the lens body from a direction perpendicular to the direction of line light emission. It is desirable that the distance between the pair of side walls, as viewed from the direction of arrangement, is partially enlarged so that it is greater than the width dimension of the lens body at the position where the lens body is sandwiched. With this configuration, even if the lens body has undulations in the longitudinal direction or variations in the diameter of the lens body, there is ample space within the casing, making it easy to insert the lens body.

[0021] According to the present invention configured in this way, the lens can be easily and accurately positioned and fixed to the casing.

[0022] A schematic diagram showing an inspection system using a line light emission device according to one embodiment of the present invention. An overall perspective view of the line light emission device in the embodiment. A side view of the line light emission device in the embodiment. (a) X-X' cross-sectional view and (b) Y-Y' cross-sectional view schematically showing a cross-section of the line light emission device in the embodiment. A schematic perspective view showing the internal structure of the line light emission device in the embodiment. An enlarged schematic diagram of the cross-section of the line light emission device in the embodiment.

[0023] <First Embodiment> Hereinafter, a line light emission device 100 according to one embodiment of the present invention will be described with reference to the drawings.

[0024] <Overview of Line Light Emitting Device 100> As shown in Figure 1, the line light emitting device 100 according to this embodiment emits line-shaped light toward the surface to be illuminated, for example, of an object (workpiece) W. The illuminated surface is photographed by an imaging device 200 such as a line sensor, and the obtained image data is taken up by an image processing device (not shown) to perform automatic inspections such as checking for defects such as scratches and dirt, or foreign matter or marks in liquids. The width of the line-shaped light irradiation is set appropriately according to the application, and can be thick or thin as long as it is appropriate for the application.

[0025] Specifically, as shown in Figures 1 to 3, the line light emission device 100 comprises a plurality of LEDs 1 arranged in a predetermined direction, a long lens body 2 extending along the direction of arrangement of the plurality of LEDs 1, a casing 3 housing the plurality of LEDs 1 and the lens body 2, and a fixing mechanism 4 for fixing the lens body 2 to the casing 3. The light from the LEDs 1 is focused by the lens body 2 and emitted as line light outside the housing. In this device, the emission direction, which is the direction in which the line light is emitted outside the housing, is perpendicular to the direction of arrangement of the LEDs. The direction perpendicular to these emission direction and arrangement direction is called the width direction. The direction of arrangement of the LEDs coincides with the longitudinal direction of the lens body.

[0026] <Configuration of each part> As shown in Figures 4 and 5, multiple LEDs 1 are mounted on the surface of a rectangular plate-shaped LED mounting substrate 10, for example, in a single row at equal intervals. Multiple rows of LEDs 1 may be mounted. Figure 4(a) is a cross-sectional view along the line X-X' in Figure 3, and Figure 4(b) is a cross-sectional view along the line Y-Y' in Figure 3.

[0027] The lens body 2 focuses the light emitted from the LED 1 into a linear shape. In this embodiment, the lens body 2 consists of a first lens body 21 and a second lens body 22, which are installed so that their installation direction (the convex direction of the lens) and optical axis coincide with each other.

[0028] The first lens body 21 and the second lens body 22 have the same curvature, dimensions, and mounting configuration. Hereafter, unless it is necessary to distinguish between them, they will simply be referred to as lens body 2.

[0029] As shown in Figures 4 to 6, the lens body 2 is a plano-convex cylindrical lens that is provided on the light-emitting side of multiple LEDs 1 and has an elongated shape along the arrangement direction. The direction of the cylindrical axis of the lens body 2 coincides with the arrangement direction. The lens body 2 is made of a resin such as plastic (for example, acrylic).

[0030] As shown in Figure 6, the cross-sectional shape of the lens body 2, when cut perpendicular to the alignment direction, is an arch shape with both ends cut out. In this cross-sectional view, the flat surface on the near side in the direction of emission is called the flat surface 2a, the outwardly bulging surface on the far side in the direction of emission is called the curved surface 2b, and the end faces of the lens body 2 that are cut out in the width direction are called the side end faces 2c and 2d. The flat surface 2a and the side end faces 2c and 2d are planar, and the flat surface 2a is perpendicular to each of the side end faces 2c and 2d.

[0031] The outer edge portion and side end surface 2d in the width direction of the flat surface 2a function as positioning surfaces that are brought into contact with the casing 3, which will be described later, and used for positioning.

[0032] As shown in Figures 2 to 6, the casing 3 houses the LED mounting substrate 10 and the lens body 2, and has a housing space that extends in the direction of arrangement. A light emission window 3X that emits a line of light is formed on the tip surface.

[0033] Specifically, the casing 3 has a pair of side wall portions 31 and 32 that extend along the direction of arrangement and face each other with respect to the lens body 2 from the width direction, and a bottom wall portion 33 that extends along the direction of arrangement and connects the pair of side wall portions 31 and 32.

[0034] As shown in Figure 6, the pair of side walls 31 and 32 are arranged to be parallel to each other. The distance between the pair of side walls 31 and 32, viewed from the direction of arrangement, is partially enlarged so that it is greater than the width dimension of the lens body 2 at the position where the lens body 2 is sandwiched. Specifically, at the position where the lens body 2 is sandwiched, a pair of recessed grooves 31c and 32c are formed on the inside of the pair of side walls 31 and 32, recessed in the width direction.

[0035] The bottom wall portion 33 is positioned opposite the light emission window 3X and perpendicular to the pair of side wall portions 31 and 32. The LED mounting substrate 10 is fixed to the inside of the bottom wall portion 33, and heat dissipation fins 5 are fixed to the outside to dissipate heat generated from the LED 1 to the outside of the housing.

[0036] The pair of side walls 31, 32 and the bottom wall 33 are made of metal (for example, aluminum) and are integrally formed by, for example, extrusion molding.

[0037] A closing plate 34 is attached to one end of the casing 3 in the direction of arrangement, which closes the opening at that end. This opening at one end functions as an insertion port for inserting the lens body 2 into the casing 3 during the assembly of the line light emission device 100.

[0038] A block body 35 is attached to the other end of the casing 3 in the direction of arrangement, to close that other end. Electrical cables 6 for supplying power to the multiple LEDs 1 are connected to the outside of the block body 35. Furthermore, when the lens body 2 is inserted into the casing 3, the block body 35 is pressed against the end of the lens body 2 in the direction of arrangement, and functions as a positioning member in the direction of arrangement.

[0039] A diffuser plate 7 is provided in the light emission window 3X of the casing 3 to equalize the illuminance distribution of the line light emitted from the lens body 2. This diffuser plate 7 is located in front of the light emission side of the lens body 2.

[0040] As shown in Figures 4 to 6, the fixing mechanism 4 fixes the lens body 2 to the casing 3 such that the optical axes of each lens body 21, 22 coincide with the optical axes of the multiple LEDs 1, and the lens body 2 is positioned at a predetermined distance from the multiple LEDs 1.

[0041] The fixing mechanism 4 fixes the lens body 2 to a pair of side walls 31 and 32 of the casing 3, and includes a pressing member 41 that presses the lens body 2 against the other side wall 32, an inclined surface 42 formed at the contact position between the pressing member 41 and the lens body 2, and a first reference surface 43 and a second reference surface 44 formed on the inside of the other side wall 32.

[0042] As shown in Figures 4 to 6, the pressing member 41 is provided on one side wall portion 31 in a manner that allows it to move back and forth in the width direction, and moves toward the lens body 2 to press against the lens body 2.

[0043] The pressing member 41 of the present embodiment is a screw that is screwed into a screw hole 31h formed so as to penetrate one side wall portion 31 in the width direction. The pressing member 41 has a cylindrical shape with a screw portion formed around it. The tip portion in its advancing direction is conical, and a recess is provided in the rear end portion. Note that no screw portion is provided in the tip portion having a conical shape.

[0044] A plurality of pressing members 41 are intermittently provided over the entire length of the lens body 2 in the arrangement direction. In the present embodiment, three pressing members 41 arranged at equal intervals are provided for each of the lens bodies 21 and 22, pressing both end portions and the central portion in the arrangement direction of the lens bodies 21 and 22.

[0045] As shown in FIGS. 4 to 6, the inclined surface 42 is formed so as to be inclined with respect to the advancing direction (width direction) of the pressing member 41 when viewed from the arrangement direction on the pressing surface of the pressing member 41 and the pressed surface of the lens body 2. The inclined surface 42 on the pressing member 41 side is referred to as a pressing-side inclined surface 42a, and the lens body 2 side is referred to as a lens-side inclined surface 42b.

[0046] The pressing-side inclined surface 42a is formed as the tip portion having the above-described conical shape of the pressing member 41. When viewed from the arrangement direction, the pressing-side inclined surface 42a is inclined at an angle of about 45 degrees with respect to the advancing direction (width direction) of the pressing member 41.

[0047] The lens-side inclined surface 42b is formed on the curved surface 2b side in the emission direction and on the side of one side wall portion 31 in the width direction when the lens body 2 is viewed from the arrangement direction. Specifically, the lens-side inclined surface 42b is formed over the entire length from one end to the other end of the lens body 2 in the arrangement direction at the outer edge portion of the curved surface 2b along one side end surface 2c of the lens body 2. The lens-side inclined surface 42b is formed as a flat surface and is inclined at the same angle as the pressing-side inclined surface 42a with respect to the advancing direction (width direction) of the pressing member 41. Note that the pressing-side inclined surface 42a and the lens-side inclined surface 42b only need to be inclined in the same direction when viewed from the arrangement direction.

[0048] In addition, in the present embodiment, in order to allow the lens body 2 to be inserted from either end in the longitudinal direction, an inclined surface is also formed on the other side wall portion 32 side in the width direction of the lens body 2.

[0049] As shown in FIGS. 4 to 6, the first reference plane 43 faces forward in the emission direction and is a plane perpendicular to the emission direction. The first reference plane 43 serves as a positioning reference for the lens body 2 in the emission direction.

[0050] As shown in FIGS. 5 and 6, the second reference plane 44 faces one side wall portion 31 and is a plane perpendicular to the width direction. The second reference plane 44 serves as a positioning reference for the lens body 2 in the width direction.

[0051] These first reference plane 43 and second reference plane 44 are formed as the inner surface of the aforementioned other concave strip portion 32c provided inside the other side wall portion 32 of the casing 3. In the present embodiment, since the other concave strip portion 32c is provided from one end to the other end in the arrangement direction of the other side wall portion 32, the first reference plane 43 and the second reference plane 44 are continuously provided over the entire length of the lens body 2 in the arrangement direction. Note that the first reference plane 43 and the second reference plane 44 may be provided intermittently. In this case, it is preferable that the first reference plane 43 and the second reference plane 44 are provided at least in front of the advancing direction of each pressing member 41.

[0052] As described above, in the present embodiment, a concave strip portion 31c is also provided on one side wall portion 31, and this concave strip portion 31c has a support surface 45 formed on the same plane as the first reference plane 43. When viewed from the arrangement direction, the distance between the first reference plane 43 and the support surface 45 is shorter than the dimension of the lens body 2 in the width direction.

[0053] In addition, one concave strip portion 31c has a guide surface 46 facing the second reference plane 44 in the width direction. When viewed from the arrangement direction, the distance between the second reference plane 44 and the guide surface 46 is longer than the dimension of the lens body 2 in the width direction. Also, the aforementioned screw hole 31h is provided at a position penetrating the guide surface 46.

[0054] Since one of the recessed portions 31c is provided extending from one end to the other in the direction of arrangement of one of the side wall portions 31, the support surface 45 and the guide surface 46 are provided continuously along the entire length of the lens body 2 in the direction of arrangement.

[0055] Furthermore, when viewed from the direction of arrangement, the width of the recess in one groove 31c is wider than the width of the recess in the other groove 32c.

[0056] <Regarding Lens Fixing> The method for fixing the lens body 2 to the casing 3 in the line light emission device 100 of this embodiment will be described below. This fixing of the lens body 2 is performed with the light emission window X of the casing 3 facing upwards and the bottom wall portion 33 facing downwards, as shown in Figure 5, that is, with the line light emission direction being vertical.

[0057] First, the operator inserts the lens body 2 into the casing 3 along the alignment direction through an opening formed at one end of the casing 3 in the longitudinal direction of the lens body 2. At this time, since the first reference surface 43 and the support surface 45 are approximately horizontal, the flat surface 2a of the lens body 2 can be placed on these surfaces for insertion.

[0058] Furthermore, it is preferable to insert the lens body 2 by placing one side end face 2c of the lens body 2 against the guide surface 46. This allows the lens body 2 to be inserted straight and makes use of the wide space formed by the wide one recessed portion 31c.

[0059] Next, the worker inserts the pressing member 41, which is a screw, into the screw hole 31h from the outside of one side wall portion 31, tightens the screw, and moves it toward the lens. As the pressing member 41, which is in contact with the lens body 2, moves toward the other side wall portion 32 of the casing 3, it presses the lens body 2 against the other side wall portion 32 of the casing 3.

[0060] Then, when the pressing member 41 presses the lens body 2 via the inclined surfaces 42a and 42b, a force is generated in a direction oblique to the direction of travel, and this force can generate component forces toward the first reference surface 43 and the second reference surface 44. As a result, the flat surface 2a of the lens body 2 is pressed against the first reference surface 43, and the other side end surface 2d is pressed against the second reference surface 44, thereby fixing the lens body 2 to the casing 3. The flat surface 2a is also pressed against the support surface 45.

[0061] In this embodiment, the lens body 2 is pressed against both the first reference surface 43 and the second reference surface 44 at a 45-degree angle, so that the flat surface 2a and the other side end surface 2d are pressed against the first reference surface 43 and the second reference surface 44 with equal force.

[0062] In this way, the lens body 2 is positioned and fixed relative to the other side wall portion 32 in the direction of emission (vertical direction) and the width direction (horizontal direction).

[0063] In this process, the lens body 2 is pressed against the first reference surface 43, thereby correcting distortion primarily in the emission direction. Furthermore, the lens body 2 is pressed against the second reference surface 44, thereby correcting distortion primarily in the width direction.

[0064] <Effects of this embodiment> With the line light emission device 100 of this embodiment configured in this way, the lens body 2 can be fixed to the casing 3 simply by advancing the pressing member 41 in the width direction after insertion of the lens body 2, making the fixing work of the lens body 2 easy.

[0065] The lens body 2 can be simultaneously positioned relative to the first reference surface 43 and the second reference surface 44 by a simple mechanism that advances the pressing member 41 in one direction. In addition, in this embodiment, since the flat surface 2a and the other side end surface 2d, which are flat surfaces, are pressed against the flat reference surfaces 43 and 44, high-precision positioning can be easily achieved.

[0066] By adjusting the tightness of the pressing members 41 located in three places, the distortion along the entire length of the lens body 2 in the alignment direction can be easily adjusted. Furthermore, the pressing members 41 are attached from the outside of one side wall portion 31 after the lens body 2 has been inserted into the casing 3, eliminating the need to pre-insert them into the casing 3, which is convenient.

[0067] By precisely positioning the two cylindrical lenses, it is possible to achieve high-quality illumination with minimal aberrations and aligned optical axes.

[0068] <Other Embodiments> The present invention is not limited to the embodiments described above. For example, the lens body in the above embodiment was a cylindrical lens, that is, a plano-convex lens, but the lens body may be a biconvex lens. In this case as well, by cutting out both ends of the lens body to form flat surfaces, positioning can be performed using these surfaces.

[0069] Furthermore, although both ends of the lens body were cut out in the above embodiment, one end may be cut out. Thus, the shape, number, or arrangement of the lens body is not limited to the above embodiment. Three or more lens bodies may be provided, or lenses of different shapes may be combined.

[0070] Furthermore, although the lens body in the above embodiment was formed by integrally creating a lens portion that focuses light and a positioning portion having a positioning surface and an inclined surface, the lens body may also consist of a lens portion that focuses light and a positioning member to which this lens portion is attached, having a positioning surface or an inclined surface.

[0071] In the above embodiment, a planar positioning surface was formed on the lens body, but the invention is not limited to this. The positioning surface that contacts the first reference surface and the second reference surface may be a curved surface or the like.

[0072] The direction of travel of the pressing member does not necessarily have to coincide with the direction perpendicular to the ejection direction. This direction of travel may be parallel to the ejection direction. The direction of travel only needs to include at least one component perpendicular to the ejection direction or one component parallel to the ejection direction.

[0073] The number of pressing members and the number of screw holes formed in the casing are not limited to three. Furthermore, if multiple screw holes are formed, it is not necessary to install screws in all of them. By pre-drilling many screw holes (for example, five) in the casing, screws can be installed in the necessary locations according to the distortion pattern of the lens body, allowing for distortion correction tailored to each individual lens body.

[0074] For example, the pressing member in the above embodiment was a screw, but it is not limited to this. The pressing member may be a spring pin or the like, as long as it can press the lens body. Alternatively, the pressing member may be a fixing device such as an extendable tension rod attached to the inner wall of the casing.

[0075] In the above embodiment, inclined surfaces were formed on both the pressing surface of the pressing member and the pressed surface of the lens body, but an inclined surface may be formed on only one of them. Furthermore, the inclined surface is not limited to a flat surface, but may also be a curved surface. The inclined surface only needs to convert the pressing force of the pressing member into an oblique force that generates component forces toward the first and second reference surfaces. For example, the pressing member side may be a rounded screw or the like, in which case the tip also functions as an inclined surface. Also, the position of the inclined surface on the lens side is not limited to the above embodiment, and may be provided elsewhere than the outer edge of the lens body, or only at the contact position with the pressing member.

[0076] In the above embodiment, the fixing mechanism had an inclined surface that was inclined with respect to the direction of travel of the pressing member, formed on the pressing surface of the pressing member or on the surface of the lens body being pressed. However, such an inclined surface does not have to be formed. For example, both the pressing surface and the surface being pressed may be surfaces perpendicular to the direction of travel of the pressing member. In this case as well, as long as the direction of travel of the pressing member includes a directional component toward both the first reference surface and the second reference surface, the lens body can be pressed against these two surfaces.

[0077] The first and second reference surfaces may be integrally formed with the side wall of the casing, or they may be formed by a reference surface forming member fixed to the inner wall of the casing. Furthermore, the first and second reference surfaces may be formed intermittently along the direction of arrangement.

[0078] The first and second reference planes are not limited to being orthogonal to each other. These planes are not parallel to the alignment direction and do not lie on the same plane, but are planes that can position the lens body in two directions perpendicular to the alignment direction.

[0079] If multiple lens elements are provided, it is sufficient if any one of them is fixed by the aforementioned fixing mechanism.

[0080] The above-mentioned line light emission device can be used not only for inspection but also for applications such as resin curing and exposure using ultraviolet light.

[0081] Furthermore, the present invention is not limited to the embodiments described above, and various modifications are possible without departing from its spirit.

[0082] According to the present invention, in a line light emission device, the lens can be easily and accurately positioned and fixed to the casing.

[0083] 100: Line light emission device 1: LED 2, 21, 22: Lens body 2a: Flat surface 2b: Curved surface 3: Casing 31: Side wall 31h: Screw hole 32: Side wall 4: Fixing mechanism 41: Pressing member 42, 42a, 42b: Inclined surface 43: First reference surface 44: Second reference surface

Claims

1. A line light emission device comprising: a plurality of LEDs arranged along a predetermined direction; a long lens body provided on the light emission side of the plurality of LEDs and extending along the arrangement direction of the plurality of LEDs; a casing housing the plurality of LEDs and the lens body; and a fixing mechanism for fixing the lens body to the casing, wherein the light from the LEDs is focused by the lens body and emitted as line light, the lens body having a flat surface and a curved surface; the fixing mechanism having: a pressing member provided so as to be able to move back and forth in the direction toward the lens body when viewed from the arrangement direction and which moves toward the lens body and presses the lens body; and a first reference surface and a second reference surface formed on the inner wall of the casing so as to be on the opposite side of the pressing member with the lens body in between when viewed from the arrangement direction, the pressing member presses the lens body so that the lens body comes into contact with both the first reference surface and the second reference surface and is fixed therein.

2. The fixing mechanism further has an inclined surface formed on at least one of the pressing surface of the pressing member or the pressed surface of the lens body, which is inclined with respect to the direction of travel of the pressing member, and the pressing member presses the lens body via the inclined surface, thereby generating a force oblique to the direction of travel, and the force causes the lens body to come into contact with both the first reference surface and the second reference surface, as described in claim 1.

3. The line light emission device according to claim 2, wherein the inclined surface is a plane formed on the surface of the elongated lens body from one end to the other in the direction of arrangement.

4. The line light emission device according to claim 2, wherein the inclined surfaces are formed on both the pressing surface of the pressing member and the pressed surface of the lens body, and these two inclined surfaces are inclined in the same direction.

5. The line light emission device according to claim 2, wherein the first reference plane and the second reference plane are perpendicular to each other, and the inclined plane is inclined at an angle of 45 degrees with respect to both the first reference plane and the second reference plane.

6. The line light emission device according to claim 1, wherein, viewed from the direction of arrangement, the direction of travel of the pressing member includes a directional component perpendicular to the direction of line light emission.

7. The line light emission device according to claim 1, wherein a plurality of the pressing members are provided intermittently along the arrangement direction.

8. The line light emission device according to claim 7, wherein the plurality of pressing members are intermittently provided along the entire length of the lens body in the direction of arrangement, and the first reference surface and the second reference surface are continuously or intermittently provided along the entire length of the lens body in the direction of arrangement.

9. The line light emission device according to claim 1, wherein the pressing member is a screw that is screwed into a screw hole formed in the casing.

10. The line light emission device according to claim 9, wherein the screw has a conical shape at its tip, and the inclined surface of the tip presses against the lens body.

11. The line light emission device according to claim 1, wherein the lens body is a cylindrical lens, and the fixing mechanism brings the flat surface into contact with either the first reference surface or the second reference surface.

12. The line light emission device according to claim 11, wherein a plurality of cylindrical lenses are provided so that their optical axes coincide with each other.

13. The line light emission device according to claim 1, wherein the casing extends along the direction of arrangement and has a pair of side walls that face each other on either side of the lens body from a direction perpendicular to the direction of line light emission, and the distance between the pair of side walls as viewed from the direction of arrangement is partially enlarged such that it is greater than the width dimension of the lens body at the position where the lens body is sandwiched.

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