JP2006275790A - Line light irradiation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a line light irradiation device that can position a reflector member and an LED accurately, can be assembled easily, does not generate any wobbling, and has a small number of components. <P>SOLUTION: The line light irradiation device comprises a casing 2; a light-emitting unit 3 for mounting a plurality of LEDs 32 on a long substrate 31 in a row or a plurality of rows; and a pair of reflector members 4 that is supported by a side plate 21 in the casing 2 and is arranged at the left/right of the light-emitting unit 3. Each reflector member 4 fixes the light-emitting unit 3 by pinching each outer surface provided at equal left/right positions from the luminous center of the light-emitting unit 3 directly or indirectly from both the sides for left/right directions, and by pressing a baseplate 22 in the casing 2 directly or indirectly for fixation for a longitudinal direction. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a line light irradiation apparatus that can irradiate line-shaped light using a plurality of LEDs, and is particularly suitably used for inspection of the presence or absence of scratches or mark reading in a predetermined irradiation region of a workpiece (product). It is about what can be done.

  Conventionally, when performing inline high-speed inspection of WEB (continuous material: film, paper, metal plate), etc., which is the object to be inspected, the surface of the flowing workpiece is successively captured as image information one after another using a line sensor camera. In the image information processing apparatus, a surface defect or the like is detected by detecting a part having a different brightness. As a lighting device (light irradiation device) used at that time, a device using a halogen lamp or a fluorescent lamp is typically known. Recently, as shown in Patent Document 1, A device in which a plurality of LEDs excellent in luminous stability, lifetime, etc. are arranged in a row has been developed.

  However, LEDs are point light sources, and even if they are arranged in a line to obtain line-shaped light, the LEDs are discontinuous as a whole, and there is a problem that uneven illuminance is generated. In particular, when an ultra-bright type LED called a power LED is used, a problem of heat dissipation also occurs, so the pitch between the light emitting portions of the LED must be increased, and the problem of uneven illuminance becomes significant.

  In view of this, the present inventors are developing a reflector member provided on the left and right sides of the LED array to effectively suppress uneven illumination.

  However, in actual assembly, it is not easy to accurately position the reflector member and the LED array, in particular, to arrange the reflector members symmetrically with respect to the optical axis of the LED. This causes a problem that high-quality light cannot be supplied. The first cause is an attachment error of the reflector member and the LED to the casing. At present, the reflector member and the board on which the LED is mounted are each attached to the casing, but due to an error in the attachment position at that time, the position difference between the reflector member and the LED array occurs. Secondly, there is a variation in the mounting position of the LED with respect to the substrate. If mechanical mounting is performed, it is possible to align the LEDs almost exactly in terms of only the LEDs, but it is difficult to prevent variations in the relative positions of the substrate and the LED rows.

An easy way to solve these problems is to improve the skill of the assembler and the processing accuracy. However, this has limitations, and costs and labor are increased accordingly.
JP 2001-215115 A

  Therefore, in the present invention, in order to solve these problems all at once, the reflector member and the light emitting unit are pressed and fixed in an assembling process, and accurate positioning between them is automatically performed. Therefore, it is an object of the present invention to provide a line light irradiation device that can be easily assembled without any variation in quality and can also suppress the number of parts.

  That is, the line light irradiation device according to the present invention includes a casing having at least a pair of left and right side plates and a bottom plate and an opening formed on the top plate side, and a plurality of LEDs on a long substrate in the longitudinal direction. And a pair of reflector members mounted on the side plate and disposed on the left and right sides of the light emitting unit, and a predetermined angle of light emitted from the LED when viewed from the longitudinal direction. The light spreading outward is reflected inward by the reflecting surface provided on the inner side surface of each reflector member, and the reflector member is set to be equal to the right and left from the light emission center of the light emitting unit. The left and right narrow pressure mechanisms configured to narrow the respective outward faces provided from both sides and match the light emission center of the light emitting unit with the symmetrical axis of the reflector member, Characterized in that a fixing mechanism for fixing the casing a light emitting unit that is positioned in the lateral direction by the mechanism.

  Here, the light emission center is basically a straight line connecting the light emitting portions of the LEDs in the central row when the LEDs are in an odd row such as one row. Strictly speaking, even with mechanical mounting, it is difficult to form a straight LED array, and when the LEDs are arranged slightly off the straight line, the variation in the light emitting part of each LED in the left-right direction A straight line indicating the average position is preferred. Actually, for example, as shown in FIG. 8, it may be set at the center between the outward faces of the LEDs most distant in the left-right direction. Moreover, when LED is an even number row | line | column, it is a straight line which shows the average center position of the light emission site | part of each LED in the left-right direction or the symmetrical centerline of right-and-left LED. Also in this case, the light emission center may be set to the center between the outward faces of the LEDs that are furthest off in the left-right direction.

  As a specific structure, the reflector member includes a member main body and a protrusion that protrudes intermittently from the bottom surface of the member main body, and the left-right direction narrow pressure mechanism is formed by the inner surface of the protrusion. The thing which narrows each outward surface of a light emission unit can be mentioned. It is more preferable that this protrusion is capable of being slightly elastically deformed in the left-right direction.

  In order to be able to narrow pressure with the reflector member without adding a special structure to the light emitting unit, the right and left side surfaces of the LED package may be narrowed with the reflector member as the left and right outward surfaces.

  In order to prevent rattling of the reflector member and the LED in the casing and to eliminate the mounting structure that places a burden on assembly such as screwing, the reflector member is slightly attached to the side plate via the concave and convex engaging portions. The reflector member is pressed against the side plate by the reaction force that the reflector member narrows the light emitting unit from the left and right, and the backlash in the left and right direction between the side plate is eliminated. What is comprised so that it may be preferable.

  Furthermore, in order to reliably eliminate the backlash in the vertical direction (direction perpendicular to the bottom plate), an elastic portion is provided between the opposing surfaces of the reflector member and the casing, and the reflector member moves toward the bottom plate by the elastic return force of the elastic portion. It is desirable that the reflector is attached to the side plate so that the vertical backlash of the reflector member is eliminated.

  Specifically, the elastic portion is integrally formed on the top of the reflector member, and an intermediate member such as a light diffusing plate is inserted between the opposing surfaces of the reflector member and the casing, whereby the elastic portion is deformed. For example, the reflector member may be urged toward the bottom.

  In order to facilitate the assembly work by assembling the bottom plate last, the fixing mechanism is to fix the light emitting unit by sandwiching the light emitting unit in the vertical direction by a facing surface provided between the bottom plate and the side plate. Is desirable.

  More specifically, the fixing mechanism includes a flange that protrudes inwardly from the inner surface of the side plate, and by attaching the bottom plate and the side plate, the surface and the bottom plate facing the bottom plate side of the flange It is preferable that the right and left side portions of the substrate in the light emitting unit are sandwiched and fixed between.

  Further, the light emitting unit may be sandwiched and fixed between the reflector member and the bottom plate.

  In order to greatly improve the heat dissipation efficiency and to prevent rattling without excessive force due to the fixing mechanism acting on the light emitting unit, a heat conduction member having viscoelasticity is provided between the bottom plate and the light emitting unit. What intervenes is preferable. This is because the heat conducting member plays a role of a cushion, and even if there are parts such as a resistor on the back surface of the substrate of the light emitting unit, the heat conducting member is deformed so as to wrap around and adheres closely.

  In addition to the above, in order to improve the efficiency of heat dissipation, a through hole is provided in a portion corresponding to each LED of the substrate, and a second heat conducting member is inserted into the through hole, and the second heat conduction is achieved. It is desirable that the member is in contact with the back surface of the LED and the heat conducting member. Furthermore, it is desirable that the contact surface between the casing and the heat conducting member is an uneven surface.

  In order to be able to flexibly cope with various lengths and to achieve standardization of manufacturing, the length of the light emitting unit is different from the length of the reflector member, and the light emitting unit is compared with one or a plurality of light emitting units arranged in series. What is comprised so that the several reflector member in series from which a number differs from a number respond | corresponds is suitable.

  As a specific example of the reflector shape, for example, when viewed from the column direction, the reflector surface forms a parabola that expands in the light irradiation direction, and the light emitted from the LED is reflected to be substantially parallel. Can be mentioned.

  As an embodiment for eliminating unevenness in illuminance and making the emitted light uniform, for example, the reflector has a diffusing surface for diffusing light from the LED at the tip of the light irradiation direction side of the reflector. What you have is considered.

  In order to obtain light with less illuminance unevenness, it is preferable to further include a light diffusing plate that is disposed on the light irradiation direction side of the LED row and transmits the light emitted from the LED while averaging at least in the row direction. . Specific examples of the light diffusing plate include a lenticular lens and a prism sheet having a line perpendicular to the column direction. Of course, a normal diffusing plate having no directionality in diffusion may be used, or a diffusion plate having a diffusing direction such as a lenticular lens may be used.

In addition, in order to prevent the temperature rise of the LED and the casing,
It is desirable to provide a flow path for flowing the cooling fluid.

  When the casing is composed of a side plate and a bottom plate so as to open in the light irradiation direction and the LED is held on the bottom plate, the bottom plate has the highest temperature. It is preferable that it is provided inside the bottom plate.

  In order to cool the LEDs uniformly and to further improve the convenience on the piping, the flow path is a path extending in the column direction, and is reciprocated at least once.

  According to the present invention having such a configuration, since the reflector member and the LED of the light emitting unit are accurately positioned, it is possible to prevent deterioration of light quality due to inaccurate positioning as in the prior art, and screw The reflector member and the light emitting unit are fixed only by pressing the members without stopping, etc., so that the assembly is extremely simple and the number of parts can be reduced as much as possible. It becomes possible to prevent rattling.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
The line light irradiation apparatus 1 according to this embodiment irradiates, for example, a predetermined irradiation region of a test object (work) with line-shaped light, and is obtained by photographing the predetermined irradiation region with an imaging device (not shown). The obtained image data is used in a product inspection system or the like that takes in an image processing apparatus (not shown) and performs automatic surface inspection for the presence or absence of scratches or the like.

  Specifically, as shown in FIGS. 1 to 5, the line light irradiation device 1 includes a casing 2, a light emitting unit 3 in which a plurality of LEDs 32 are mounted on a long wiring substrate 31, and a casing 2. A pair of reflector members 4 supported by the side plates 21 and disposed on the left and right sides of the light emitting unit 3 are provided. In the following description, the row direction of the LEDs 32 is also referred to as a longitudinal direction, the direction perpendicular to the longitudinal direction and perpendicular to the side plate 21 of the casing 2 is defined as the left-right direction, the direction perpendicular to the longitudinal direction and the bottom plate 22 of the casing 2. For convenience, the direction orthogonal to the vertical direction will be referred to as the vertical direction.

  Each part is described in detail below.

  As shown in FIGS. 1 to 3, the casing 2 has a rectangular parallelepiped shape made of a long metal, and includes a pair of left and right side plates 21, a top plate 24, a bottom plate 22, and an end plate 23.

  The side plate 21 and the top plate 24 are integrated, for example, extruded (pulled). A plurality of grooves extending in the longitudinal direction are provided on the outer surface of the side plate 21, and the protrusions formed therebetween serve as the radiation fins F. A top plate 24 extends inwardly from the top of the side plate 21, and a strip-shaped opening M for emitting line light is formed between the left and right top plates 24. The bottom plate 22 is a thick flat plate that is extruded (drawn) and molded in the same manner as the side plate 21, and is in close contact with the bottom surface of the side plate 21 that is spaced apart with the inner surfaces facing each other by screwing or the like. The bottom plate 22 is provided with a flow path R extending in the longitudinal direction for flowing the cooling fluid. As shown in FIG. 7, the circulation path R is configured to reciprocate at least once so that the inlet and the outlet open to the same end plate 23. In addition, when using this distribution route R, it is necessary to attach the cover member 25 (it shows with an imaginary line in FIG. 3. This cover member 25 is not attached in another figure.) To the bottom of the baseplate 22. FIG. . The end plate 23 is a rectangular plate attached to each end face of the side plate 21.

  As shown in FIGS. 2 to 4, the light emitting unit 3 is a device in which a plurality of LEDs 32 are mechanically mounted on a surface of a belt-like printed wiring board 31 in a line substantially linearly with the optical axis aligned in a certain direction. is there. The LED 32 is a so-called power LED that can continuously pass a current of 200 mA or more. In this embodiment, the LED 32 is a surface-mounting device in which the LED element 322 is disposed in the center of a thin rectangular plate 321. Of the type. For example, the LEDs 32 are arranged so that the LED elements 322 are arranged in a substantially straight line at a predetermined interval.

  The reflector member 4 includes a member main body 41 having a long plate shape as shown in FIGS. 2 to 5, and a plurality of protrusions 42 (one in each end in this example) protruding integrally from the outside of the bottom surface of the member main body 41. 1), and is attached to the inner side surface of the casing side plate 21 via an uneven engagement portion. The concave-convex engaging portion is a concave groove 51 and a protrusion 52 extending in the longitudinal direction that have a slight backlash and can be slidably engaged, and the concave groove is formed by sliding the reflector member 4 and the side plate 21 in the longitudinal direction. The reflector member 4 is configured to be attached to the side plate 21 by engaging the 51 and the protrusion 52.

  The inner side surface 4a of the member main body 41 is inclined, and when each reflector member 4 is attached to the side plate 21, the distance between the inner side surfaces 4a gradually increases toward the opening M. ing. In addition, substantially the entire area of the inner side surface 4a is made into a mirror surface by vapor deposition surface processing so as to function as a reflection surface that reflects light from the LED 32. In addition, the opening side tip portion of the inner side surface 4a may be formed as a partially diffusing surface by forming fine irregularities or by painting it with white. The inclination of the inner surface 4a is a parabola that extends toward the opening when viewed from the longitudinal direction, and is configured to reflect the light emitted from the LED 32 so as to be substantially parallel to the optical axis. It doesn't matter.

  As the reflector member 4, metal or resin can be used. In this embodiment, a plurality of reflector members 4 are held in series on one side plate 21, but one reflector member 4 may be provided on one side plate.

  In this embodiment, as specifically shown in FIGS. 3 and 4, in the left-right direction, the left and right side surfaces 32a, 32b of the LED package 321 are narrowed directly or indirectly from both sides by the respective reflector members 4. A left and right narrow pressure mechanism configured to press is provided, and a fixing mechanism for fixing the light emitting unit 3 positioned in the left and right direction by the left and right narrow pressure mechanism to the casing 2 is provided in the vertical direction.

  First, the left and right narrow pressure mechanism will be described in detail. In this embodiment, the left and right side surfaces 32a and 32b of the LED package 321 in the corresponding part are sandwiched between the inner surfaces of the plurality of protrusions 42 provided on the reflector member 4. In the natural state, the width between the inner surfaces of the left and right protrusions 42 is slightly narrower than the left and right width dimensions of the LED package 321, and when the LEDs 32 are sandwiched by these protrusions 42, the protrusions 42 are slightly elastically deformed to narrow the LED 32 (see FIG. The arrow next to 4 indicates the direction of narrow pressure). On the other hand, the reflector member 4 is urged outward in the left-right direction by the reaction force, and is pressed against the casing side plate 21 without backlash.

  Next, the fixing mechanism will be described in detail. In this embodiment, the flange 26 is integrally protruded inward from the bottom inner surface of the casing side plate 21, and the casing bottom plate 22 is fastened to the casing side plate 21, whereby the surface of the flange 26 facing the bottom plate 22 side is The left and right side portions of the substrate 31 of the light emitting unit 2 are sandwiched and fixed with the bottom plate 22 (the vertical arrows in FIG. 4 indicate the urging direction by the flange portion 26). A heat conducting member 9 is interposed between the back surface of the light emitting unit 3 and the inner surface of the casing bottom plate 22. The heat conducting member 9 is a belt-like flat plate having substantially the same width as the wiring board 31 and is formed of a material having predetermined viscoelasticity and insulating properties such as silicone. When the side plate 21 and the bottom plate 22 are fastened, the heat conducting member 9 is deformed so as to dent a component such as a resistor disposed on the back side of the wiring board 31, and ideally makes surface contact with the wiring board 31. Thus, the heat conduction efficiency from the LED 32 to the bottom plate 22 is increased.

  In the present embodiment, a plurality of triangular protrusions 7 (one in each end, two in total in this example) that are elastic portions that are elastically deformable in the vertical direction are further provided from the top surface of the reflector member 4. It is protruding.

In a state where the reflector member 4 is attached to the casing side plate 21, a gap is formed between the reflector member 4 and the casing top plate 24, and a strip-shaped diffusion plate 8 having a constant thickness is slid along the longitudinal direction in the gap. By inserting, a force in the immersion direction acts on the protrusion 7 from the top plate 24 through the diffusion plate 8, and the reflector member 4 is urged toward the bottom plate 22 by the elastic restoring force of the protrusion 7. It is. As a result, the backlash in the vertical direction of the reflector member 4 due to the concave-convex engagement is eliminated, and the reflector member 4 is positioned in the vertical direction.

  Next, an example of the assembly method of this line light irradiation apparatus 1 is demonstrated easily.

  First, the end plate 23 is attached to one end portion in the longitudinal direction of the side plate 21.

  Next, the reflector member 4 is slid and inserted from the other end portion in the longitudinal direction of the side plate 21 and engaged with the side plate 21 (this state is shown in FIG. 2).

  Next, the light emitting unit 3 is fitted from the bottom so that the LED package 321 is sandwiched between the left and right protrusions 42. One or more heat conductive members 9 are attached to the back surface of the light emitting unit 3 so that the lengths are uniform.

  Next, the bottom plate 22 is attached.

  Next, the diffusion plate 8 is slid and inserted from the other end portion in the longitudinal direction of the side plate 21, and the opening is closed with the diffusion plate 8 (this halfway state is shown in FIG. 6).

  Finally, the end plate 23 is attached to the other side end of the side plate 21 in the longitudinal direction.

  Note that this assembling method is merely an example, and other procedures are conceivable. For example, the procedure for attaching the bottom plate 22 and inserting the diffusion plate 8 may be reversed. In addition, after the reflector member 4 is inserted into the side plate 21, the end plate 23 may be attached to one end portion in the longitudinal direction of the side plate 21.

  Thus, according to the present embodiment, the reflector member 4 sandwiches the LED 32 mounted on the light emitting unit 3 from the left and right to narrow the pressure while the light emitting unit 3 is freely movable with respect to the casing 2. Therefore, the right and left positioning of the LED 32 with respect to the reflector member 4 can be performed accurately and without difficulty, and as a result, the quality of light for each product can be maintained at a high level.

  Moreover, since the reflector member 4 and the light emitting unit 3 are pressed against the casing 2 by a reaction force such as a narrow pressure applied to the LED 32, it is possible to prevent rattling of the reflector member 4 and the light emitting unit 3 in the casing 2.

  In addition, the mounting structure that increases the number of parts, which imposes a burden on assembly such as screwing, is eliminated as much as possible, so that labor and cost can be greatly reduced.

  In particular, in this embodiment, since the light emitting unit 3 is pressed against the casing bottom plate 22 via the heat conducting member 9 by the fixing mechanism, the heat generated from the LEDs 32 can be efficiently transmitted to the casing 2 and radiated.

  In addition, this invention is not restricted to the said embodiment (In the following description, the same code | symbol is attached | subjected to the member corresponding to the said embodiment as needed.).

  As the fixing mechanism, the light emitting unit 3 may be sandwiched and fixed between the reflector member 4 and the bottom plate 22.

Specifically, for example, the light emitting unit 3 may be pressed by providing a surface of the reflector member 4 that faces the casing bottom plate 22 such as a bottom surface of the member main body 41 or a step provided on the protrusion 42. In this case, the protruding body 7 may be interposed between the reflector member 4 and the casing 2 in the longitudinal direction as in the above embodiment. The reflector member 4 is urged in the direction of the bottom plate 22 by the elastic restoring force of the projecting body 7, so that the vertical play of the reflector member 4 attached to the side plate 21 can be eliminated and an unreasonable force is applied to the light emitting unit 3. It is because it can press-fix suitably.

  Further, for example, in the vertical direction, the casing top plate 24 and the protruding body 7 that is an elastic portion may be brought into direct contact without the diffusion plate 8 being interposed. The elastic portion may be provided on the casing side. In short, the elastic portion may be interposed between the opposing surfaces of the reflector member and the casing, such as between the reflector member bottom surface and the casing bottom plate in the longitudinal direction. .

  Conversely, in the left-right direction, spacers having the same left-right width dimension may be interposed between the left and right protrusions 42 and the left and right side surfaces 32a, 32b of the LED package 321.

  Further, the pressure may be directly reduced by the inner side surface 4a of the reflector member 4 without providing the protrusion 42. Further, the left and right outward surfaces sandwiched in the light emitting unit 3 are not limited to the left and right side surfaces 32 a and 32 b of the LED package 321, and may be any positions that are equal to the left and right from the light emission center. It may be formed by, for example.

  In addition, the reflector member may apply a force in a diagonally inward direction, that is, a direction in which the vertical direction and the horizontal direction are combined to the LED. In this case, the reflector member may be provided with an inclined surface that presses the left and right corners of the LED diagonally inward.

  In addition, various modifications such as a heat dissipation method and a casing shape are possible, and the LEDs are not limited to one row, but may be two rows or three rows. When the LEDs are in a plurality of rows, the outer surface of the outermost LED may be narrowed.

  Further, the heat conducting member is not always necessary, and can be omitted depending on the use mode. The LED is not limited to a power LED or chip type, and may be a type that operates with a normal current or a shell type. Further, a plurality of light emitting units may be connected in series or in parallel instead of incorporating one light emitting unit in the casing. In that case, the reflector member may correspond to the light emitting unit on a one-to-one basis, or a reflector member that is longer or shorter than the light emitting unit may be used. If it does in this way, the line light irradiation apparatus of various length can also be manufactured using few types of light emitting units and reflector members.

  As described in detail above, according to the present invention, a line light irradiation device that can easily perform accurate positioning of the LED and the reflector member, prevent rattling thereof, and can be configured with a small number of parts. Can be provided.

1 is an overall perspective view showing a light irradiation apparatus according to an embodiment of the present invention. The assembly middle view which shows the inside of the light irradiation apparatus in the embodiment. The cross-sectional view of the light irradiation apparatus in the same embodiment. The principal part enlarged view in FIG. The perspective view which shows the reflector member in the embodiment. The assembly process figure of the light irradiation apparatus in the embodiment, and its partial enlarged view. The bottom view which shows the distribution channel of the light irradiation apparatus in the embodiment. Explanatory drawing explaining the light emission center in this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Light irradiation apparatus 2 ... Casing 21 ... Side plate 22 ... Bottom plate 26 ... Gutter part 3 ... Light emission unit 31 ... Board | substrate 32 ... LED
32a, 32b ... Faces outward (left and right sides of the LED)
4 ... Reflector member 4a ... Inner side surface 41 ... Member main body 42 ... Protrusion 7 ... Elastic part (projecting body)
8. Light diffusion plate (intermediate member)

Claims (11)

A casing that has at least a pair of left and right side plates and a bottom plate and has an opening formed on the top plate side, and a light emission that is positioned on the bottom plate and has a plurality of LEDs mounted in a row in the longitudinal direction on a long substrate A light source unit and a pair of reflector members disposed on the left and right sides of the light-emitting unit, and the light emitted from the LEDs as viewed from the longitudinal direction is spread outward by a predetermined angle or more. The reflection surface provided on the inner surface is configured to be reflected inward,
The left and right narrow pressures are configured so that the respective outward faces provided at equal positions on the left and right sides from the light emission center of the light emitting unit are narrowed from both sides by the respective reflector members, and the light emission center of the light emitting unit is aligned with the left and right symmetrical axes of the reflector members. A line light irradiation apparatus comprising a mechanism and a fixing mechanism for fixing a light emitting unit positioned in the left-right direction by the left-right narrow pressure mechanism to a casing.   The reflector member includes a member main body and a protrusion that protrudes intermittently from the bottom surface of the member main body, and the left-right direction narrow pressure mechanism is provided on each outward surface of the light emitting unit by the inner surface of the protrusion. The line light irradiation apparatus according to claim 1, wherein the pressure is narrowed.   The line light irradiation device according to claim 1, wherein the left and right outward surfaces are left and right side surfaces of an LED package.   The reflector member is attached with a slight backlash to the side plate via the concave / convex engaging portion, and the reflector member presses against the side plate by the reaction force that narrows the light emitting unit from the left and right. The line light irradiation device according to any one of claims 1 to 3, wherein a backlash in a lateral direction between the side plate and the side plate is eliminated.   An elastic portion is provided between the opposing surfaces of the reflector member and the casing, and the elastic restoring force of the elastic portion urges the reflector member in the direction of the bottom plate so that the vertical play of the reflector member attached to the side plate is eliminated. The line light irradiation apparatus of Claim 4 comprised in these.   The elastic portion is provided integrally on the top of the reflector member, and an intermediate member such as a light diffusing plate is inserted between the opposing surfaces of the reflector member and the casing, so that the elastic portion is deformed and the reflector member is attached in the bottom direction. The line light irradiation device according to claim 5, wherein   The line light irradiation device according to any one of claims 1 to 6, wherein the fixing mechanism sandwiches and fixes the light emitting unit in a vertical direction by an opposing surface provided between a bottom plate and a side plate.   The fixing mechanism includes a flange that protrudes inwardly from the inner side surface of the side plate, and the light emitting unit between the surface facing the bottom plate in the flange and the bottom plate by attaching the bottom plate and the side plate. The line light irradiation apparatus according to any one of claims 1 to 7, wherein the line light irradiation apparatus is configured so as to be sandwiched and fixed.   The line light irradiation device according to any one of claims 1 to 6, wherein the fixing mechanism sandwiches and fixes the light emitting unit between the reflector member and the bottom plate.   The line light irradiation apparatus according to claim 7, wherein a heat conductive member having viscoelasticity is interposed between the bottom plate and the light emitting unit. The length of the light emitting unit is different from the length of the reflector member, and one or a plurality of light emitting units arranged in series corresponds to a plurality of reflector members arranged in series different from the number of light emitting units. The light irradiation apparatus according to claim 1.