JP2009093988A - Lighting system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multiple-light-source direct hang type lighting system realizing thickness reduction and increasing use efficiency of light. <P>SOLUTION: The lighting system includes a reflecting member 1, a plurality of linear light sources 2, a light control member 3 and a diffusing member 4 in this order. The light sources 2 are disposed in parallel with one another on the same plane. The reflecting member 1 alternately has recesses surrounding the respective light sources 2 and coupling parts. Each recess in the reflecting member 1 has a curved surface symmetric centering around a part closest to the light source 2 and has a form that the part closest to the light source 2 is protruded toward the light source such that light reflected from the reflecting member 1 and incident upon the light control member 3 complements light directly incident upon the light control member 3 from the light source to unifomize light incident upon the entire of the light control member 3. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an illumination device and an image display device, and in particular, can uniformly distribute light emitted from a linear light source such as a CCFL (Cold Cathode Fluorescent Tube), thereby reducing the thickness and improving light utilization efficiency. The present invention relates to a direct backlight device and a liquid crystal display device using the same.

Taking an illumination device for an image display device as an example, the edge light system that guides the light of the light source arranged on the side of the light guide plate in the front direction with the light guide plate and makes it uniform with the diffusion sheet, and the light source on the back side of the illumination surface And a direct system in which light is made uniform with a diffusion sheet.
The direct type has a tendency to increase in thickness because it has a light source on the back of the device. For this reason, in fields where thinness is required such as mobile phones, mobile PCs, car navigation systems, etc. The edge light method that can be realized is the mainstream.

  On the other hand, in recent years, there has been an increasing demand for larger displays and higher brightness mainly in televisions and personal computer monitors. In particular, with the increase in the size of the display, in the edge light system, the ratio of the length of the peripheral portion where the light source can be arranged to the display area decreases, and the amount of light is insufficient, so that sufficient luminance cannot be obtained. Further, the edge light system has a problem that the weight of the light guide plate increases as the display becomes larger. As described above, in the edge light system, it has become difficult to meet market demands such as an increase in display size and brightness in recent years.

Therefore, in large display applications, a direct system using a plurality of light sources is adopted. In this method, the ratio of the luminous flux emitted from the light source is high, and the number of light sources can be increased freely.
That is, since the amount of light can be increased freely, the required high brightness can be easily obtained, and there is no reduction in brightness due to an increase in size. Furthermore, since a light guide plate for directing light in the front direction is not necessary, the weight can be reduced.

  However, the direct method needs to solve unique problems such as elimination of lamp image, thinning, and energy saving. In particular, in a direct illumination system using a plurality of light sources, the energy of emitted light is large at positions facing each light source and small at positions facing between the light sources. For this reason, the lamp image appears as brightness unevenness far more conspicuous than in the edge light system. Therefore, it is difficult to eliminate the lamp image by means conventionally used in the edge light system, that is, means such as a diffusion film in which a diffusion material is applied to the film surface.

  Therefore, in order to eliminate the lamp image, a diffusion sheet containing a diffusion material is widely used. For example, in order to obtain good diffusibility and light utilization efficiency, inorganic particles and cross-linked organic fine particles are blended with a light diffusing material in a base resin such as methacrylic resin, polycarbonate resin, styrene resin, and vinyl chloride resin. Thus, a light diffusion sheet is produced.

  However, in the method using a diffusion sheet containing these diffusing materials, not only the light is easily absorbed into the diffusing material, but also the light diffuses in unnecessary directions, so that the light use efficiency is reduced and from the viewpoint of energy saving. It is not preferable. Further, the lamp image can be reduced by arranging a large number of light sources close to each other. However, since the number of light sources increases, a large amount of power is consumed, which causes a problem of cost increase.

  There has also been proposed a method of erasing the lamp image by giving the reflecting sheet a unique shape (Patent Document 1). However, in the shape of the reflective sheet described in the patent document, since there is a convex surface for connecting adjacent concave surfaces, it is difficult to further reduce the thickness. Further, this convex surface may cause uneven brightness.

  Further, a direct type backlight device (Patent Document 2) is proposed in which a luminance adjusting means having a linear transmittance of 20% to 90% is installed facing a plurality of light sources. However, in this apparatus, even if the light traveling direction can be controlled, since the brightness adjusting means is installed facing each light source, the lighting apparatus cannot be thinned.

  In a large illuminating device, the demand for thinning is not as strict as that of a cellular phone or mobile personal computer, but it is necessary to reduce the thickness by reducing the distance between the light source and the diffusion sheet or by reducing the optical film. However, if the light source and other members are brought close to each other or the optical film is reduced, a lamp image is likely to be generated, and uniform brightness cannot be obtained.

  In order to realize energy saving, it is necessary to increase the efficiency of light utilization. The direct method can increase the number of light sources as described above, and can easily obtain high luminance. However, an increase in the number of light sources is not preferable from the viewpoint of energy saving. Furthermore, if a large amount of diffusion material is used for the diffusion sheet to eliminate the lamp image, the light utilization efficiency is greatly reduced.

Japanese Patent No. 2852424 JP 2000-338895 A

Accordingly, an object of the present invention is to provide an illumination device of a direct type of a plurality of light sources that does not generate a lamp image even when a light source and another member are brought close to each other, and an image display device using the same.
Another object of the present invention is to provide a lighting device of a direct type with a plurality of light sources, which can be thinned and does not require the use of a large amount of diffusing material for eliminating the lamp image, and can improve the light utilization efficiency. It is to provide an image display device used.

In order to solve the above problems, the present inventors have found the following points and completed the present invention.
First, in a direct illumination system using a plurality of light sources, the energy of emitted light is large at a position facing each light source and small at a position facing between adjacent light sources. Therefore, a concave portion is provided on the reflecting member, and the shape of the concave portion is set so that the reflected light is less directly above each light source and proceeds at a position opposed to each light source, and a connecting portion that separates the respective concave portions is provided. As a result, the shape of the reflecting member has been optimized so that the incident light from the adjacent light sources can enter the light control member without overlapping while the reflected light and direct light emitted from one light source complement each other. . As a result, even if the distance between the light source and the diffusion sheet is made closer than before, the position facing the light source and the energy of the light emitted from the other are equal, and it is possible to simultaneously realize thinning and elimination of the lamp image. .

  Secondly, even if there are a plurality of light sources, the incident light from adjacent light sources does not easily overlap each other and enter the light control member. Therefore, by giving a specific shape to the optical control member, the light control member It has been found that the incident light on can be brought close to a direction perpendicular to the main surface of the diffusing member. As a result, the traveling direction of light gathers in a direction perpendicular to the main surface of the diffusing member, and it has also been found that uniform luminance can be maintained in the surface.

  Third, since the traveling direction of the incident light to the diffusing member is gathered in a direction perpendicular to the main surface of the diffusing member, the incident light passes through the specific diffusing member, and the rear of the light Scattering can be suppressed to a high degree, resulting in a uniform surface light source when viewed not only in the front direction but also from an oblique direction, and greatly reduces the use of diffusing materials that reduce light utilization efficiency It was found that high light utilization efficiency was achieved.

That is, the present invention made based on the above examination results includes a plurality of linear light sources arranged in parallel to each other on the same plane, a plurality of concave portions surrounding each linear light source, and a connecting portion connecting the concave portions. And a light control member disposed on the opposite side of the reflection member across the linear light source, and a diffusion member disposed on the light emission side of the light control member. It is a lighting device.
The concave portion of the reflecting member has a symmetrical curved surface centered on a portion closest to the light source when viewed from the longitudinal direction of the light source, and has a shape in which a portion closest to the light source protrudes toward the light source. . Furthermore, the shape of the reflecting member is such that the incident light incident on the light control member is directly incident from a single linear light source, is emitted from the linear light source, is reflected by the reflecting member, and is incident. The incident light incident on the light control member from the single linear light source is the direct light and the reflected light from the linear light source adjacent to the linear light source. Is set so as not to substantially contain. When reflected light from a plurality of linear light sources is incident on the light control member, the reflected light has a light intensity in which a substantially M-shape centered directly above the light control member in each linear light source is continuous. May be. In the reflecting member, the width of the concave portion (that is, the width in the left-right direction orthogonal to the longitudinal direction of the light source) is preferably 5/6 to 1/1 of the width of the connecting portion.

  The light control member may emit 60% or more of the incident light while being oriented in a direction perpendicular to the main surface of the light control member, and the light control member usually has at least a plurality of protrusions extending in parallel. Each of the protrusions may have a surface perpendicular to the main surface of the light control member.

  The backscattering probability by the diffusing member may be 10% or less. In the diffusing member, diffusing particles having a refractive index different from that of the matrix resin may be dispersed in the transparent matrix resin.

The lighting device of the present invention can be thinned. For example, the distance from the bottom of the reflecting member to the light emitting side of the diffusing member is preferably 20 mm or less.
The present invention also includes an image display device in which a transmissive display element is provided on the light emitting side of the illumination device.

In the specification, “the incident light incident on the light control member includes direct light and reflected light from a certain linear light source, but direct light and reflected light from a linear light source adjacent to the linear light source. "Substantially does not contain" means that in any section of the light control member, the linear shape adjacent to the linear light source with respect to the combined light intensity of the direct light and the reflected light from one linear light source. It means that the light intensity of direct light and reflected light from the light source is 15% or less.
In addition, “the light control member orients 60% or more of the incident light in a direction perpendicular to the main surface of the light control member” means that the incident light to the light control member passes through the light control member. It means that the ratio of the light that is emitted in the direction in which the emitted light is closer to the vertical direction than the traveling direction of the incident light with respect to the main surface of the light control member is 60% or more.

  In the illuminating device of the present invention, direct light and reflected light from the light source complement each other, and even if there are multiple light sources, incident light from adjacent light sources does not overlap with the light control member, respectively. Even if the positions of the light source and the light control member are close to each other between the light source and the light source, not only the incident light incident on the entire light control member can be made uniform, but also the lighting device can be made thin.

  In addition, in order to utilize such a property of incident light, the light control member can direct the incident light in a direction perpendicular to the main surface of the light control member, which is usually the most important as a lighting device. The light traveling in the direction perpendicular to the main surface of the light control member increases. As a result, light traveling to an unnecessary angle is reduced, and the light use efficiency of the light illumination device can be improved.

  Furthermore, since light is emitted in a direction perpendicular to the main surface of the light control member, the incident light on the diffusing member is also in a direction perpendicular to the main surface. % Or less. Thereby, the light absorbed by the diffusing material in the diffusing member and the light lost by the backscattering can be reduced, and the light utilization efficiency can be improved.

  By providing a transmissive display element on the lighting device of the present invention, a thin display can be realized and a screen display device with high light utilization efficiency can be easily obtained.

  The present invention will be more clearly understood from the following description of preferred embodiments with reference to the accompanying drawings. The drawings are not necessarily drawn to scale, but are exaggerated in illustrating the principles of the invention. In the accompanying drawings, the same part number in the plurality of drawings indicates the same part.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram for explaining one embodiment of the illumination device of the present invention, and shows a cross section orthogonal to the longitudinal direction of a linear light source disposed in the illumination device. As shown in FIG. 1, in the lighting device, the reflecting member 1 is disposed in the lower part of the case C opened upward, and the plurality of linear light sources 2 are flush with the concave portion 11 provided in the reflecting member 1. The light control member 3 is arranged in parallel with each other on the upper side, that is, on the opposite side of the reflection member 1 across the linear light source 2, and the diffusion member is disposed on the light emission side of the light control member 3. 4 is arranged. Further, the liquid crystal panel 5 is supported in the opening of the case C above the diffusion member 4.

(Reflective member)
As shown in FIG. 1, the reflecting member 1 has recesses 11 surrounding the linear light sources 2 from below and flat connecting portions 12 that connect the recesses alternately and continuously. In addition, the connection part 12 is normally arrange | positioned on the same plane mutually.
The light emitted from the light source 2 is divided into direct light 7 that directly enters the light control member 3 and reflected light 8 that is reflected by the concave portion of the reflection member and enters the light control member 3. Most of the linear light source 2 is present below the connecting portion 12 except for a part of the upper part, and viewed from the longitudinal direction of the light source 2 (the direction perpendicular to the paper surface of FIG. 1). Therefore, even if the linear light sources 2 are adjacent to each other, the incident light incident on the light control member 3 is composed of the direct light 7 and the reflected light 8 from the single linear light source 2. In addition, direct light and reflected light from the linear light source adjacent to the linear light source are substantially excluded and are not included.

  The concave portion 11 has a curved surface symmetric with respect to a portion closest to the light source, in this example, a portion directly below the light source 2 in the paper surface orthogonal to the longitudinal direction of the light source 2, and as shown in FIG. The protrusion 13 which is the portion closest to the light source has a shape protruding toward the light source. The shape of the curved surface of the recess 11 is not particularly limited as long as the reflected light that complements the direct light from the light source 2 is generated. For example, a double ellipse as shown in FIG. It preferably has a shape.

  In addition, by providing the protrusions 13 in the respective concave portions 11, it is possible to adjust the reflected light distribution so that the reflected light concentrates the light intensity at the portions facing each other between the light sources. As a result, the light intensity of the reflected light can draw a substantially M-shape centered on the portion directly above the light control member in each linear light source. And since a reflective member is provided with a recessed part and a connection part continuously, when the reflected light from the linear light source enclosed by each recessed part injects into a light control member, it centers on each linear light source. The light intensity in which the substantially M shape is continuous can be shown.

  In the double ellipse shape, the light intensity when the reflected light is incident on the light control member 3 can be adjusted by adjusting the angle at which the major axes of the ellipses intersect (the inclination angle of the ellipse), Since the light is incident on the light control member at a position between the light source 2 and the light source 2, it is possible to suppress only the light directly above the light source 2 from being brightened, and uniform light intensity in the entire light control member. For example, from the viewpoint of making the light intensity in the entire light control member uniform, the inclination angle of the ellipse is preferably about 160 to 200 °, more preferably about 170 to 190 °.

  The coupling portion 12 is a concave portion so that incident light incident on the light control member from the single linear light source does not substantially include direct light and reflected light from the linear light source adjacent to the linear light source. 11, the width of the connecting portion 12 (Wp: dimension in the horizontal direction on the paper surface) and the width of the concave portion 11 (Wc: dimension in the horizontal direction on the paper surface). Although not particularly limited as long as it can be achieved, for example, the width of the recess 11 is preferably about 5/6 to 1/1 of the width of the connecting portion 12, and more preferably about 17/20 to 19/20.

  The material of the reflecting member 1 is not particularly limited as long as it can generate specularly reflected light, and a known reflecting member can be used. From the viewpoint of lightness, a metal or the like is formed on a resin molded product formed from an olefin resin or the like. It is preferable to use a reflective member (for example, a reflective sheet) coated or vapor-deposited.

(Linear light source)
The plurality of linear light sources 2 are arranged in parallel to each other on the same plane, and each linear light source is arranged at the center in the width direction (that is, the left-right direction on the paper surface) of the recess 11 surrounding the light source. The light source is not particularly limited as long as it has a linear shape, but is usually a fluorescent tube such as a cold cathode fluorescent tube (CCFL). The position at which the light source 2 is disposed is not particularly limited as long as it is between the light control member 3 and the reflecting member 1 while being at the center in the width direction of the recess 11. It is preferable to arrange the light source 2 on the surface. By arranging the light source in such a place, the reflected light is unlikely to return to the light source itself, and the light absorbed by the fluorescent tube can be reduced.

  The distance between the light sources and the thickness of the lighting device can be freely selected according to the required luminance and the shape of the reflecting member. For example, from the viewpoint of achieving both weight reduction and high luminance, light control is performed from the bottom surface of the reflecting member. The ratio of the distance to the member (L1) and the distance between adjacent light sources (W1) is preferably about (L1) / (W1) = 55/100 to 80/100, preferably about 60/100 to 70/100. More preferred.

(Light control member)
The light control member 3 functions to make the traveling directions of the direct light 7 and the reflected light 8 from the light source 2 closer to the normal direction (or vertical direction) with respect to the main surface of the light control member 3. Therefore, it is preferable that the light control member 3 emits 60% or more of the incident light oriented in a direction perpendicular to the main surface of the light control member. The light control member may emit 70% or more of the incident light, more preferably 80% or more of the incident light, with the light control member oriented in a direction perpendicular to the main surface of the light control member.

  By providing a reflecting member having such a specific shape, even if there are a plurality of light sources, incident light from adjacent light sources does not enter the light control member in an overlapping manner, but from a single linear light source. Incident light incident on the light control member substantially does not include direct light and reflected light from the linear light source adjacent to the linear light source.

Therefore, as shown in FIG. 3, which is a cross-sectional view taken along a plane orthogonal to the longitudinal direction of the linear light source 2, for example, the light control member 3 has at least so that the amount of light traveling in the vertical direction is relatively large. The light emitting surface has a plurality of protrusions 30 extending in parallel with the longitudinal direction of the light source 2 and the light source, and each protrusion 30 is a vertical surface 31 perpendicular to the main surface of the light control member 3. And a right triangle having an inclined surface 32 inclined.
The range of the angle (vertical angle) formed by the vertical surface 31 and the inclined surface 32 is such that the light control member 3 determines the traveling direction of the incident light in a direction normal to the main surface of the light control member 3 (or vertical). Although it does not restrict | limit as long as it can approach (direction), For example, about 30-75 degrees is preferable, More preferably, it is about 40-70 degrees. The pitch of the ridges 30 is preferably about 0.01 to 0.5 mm, more preferably about 0.05 to 0.3 mm.

  Further, as shown in FIG. 4, the light control member 3 has a plurality of ridges 30 extending in parallel on both the light emitting side and the light incident side, and each of the ridges 30 corresponds to the light control member 3. You may have a perpendicular surface perpendicular | vertical with respect to a main surface. Thus, when it has the protrusion 30 on both surfaces, after it radiate | emits from the light control member 3, the ratio of the light which advances to a perpendicular direction can be raised.

  Such a light control member 3 is preferably formed of a light-transmitting material. If it is so-called transparent, any of a thermoplastic resin, a thermosetting resin, and a photocurable resin can be preferably used. For example, such resins include (meth) acrylic resins, (meth) acrylic-styrene copolymer resins, styrene resins, aromatic vinyl resins, olefin resins, ethylene-vinyl acetate copolymer resins, Examples thereof include vinyl chloride resin, vinyl ester resin, polycarbonate, fluorine resin, urethane resin, silicone resin, amide resin, imide resin, polyester resin, epoxy resin, phenol resin, urea resin, melamine resin, and the like. For example, the refractive index of such a transparent resin is preferably about 1.48 to 1.62, and more preferably about 1.50 to 1.60.

  The light control member may be directly molded from the transparent resin using a known or conventional method such as injection molding, compression molding, transfer molding, or the like according to the characteristics of the resin, or molding a predetermined shape. The body may be cut and produced by dicing.

(Diffusion member)
With respect to the diffusing member used for reducing the lamp image and widening the viewing angle, in the present invention, the light control member causes the light traveling direction to approach the direction perpendicular to the main surface of the light control member. The backscattering probability can be reduced to 10% or less, and the amount of the diffusing material in the diffusing member can be reduced. Therefore, it is possible to eliminate light absorption by the diffusing material and light utilization efficiency reduction due to backscattering.

  In the diffusing member 4, it is preferable that diffusing particles or a diffusing material having a refractive index different from that of the matrix resin is dispersed in the transparent matrix resin. The transparent matrix resin is exemplified by the light control member. A transparent resin can be used.

  The diffusing material may be formed from the same organic material as the transparent resin, or may be formed from an inorganic material such as glass particles. The diffusing material may be substantially spherical, and the average particle diameter is preferably, for example, about 1 to 20 μm, more preferably about 2 to 18 μm. If the particle diameter is too small, the light diffusion efficiency may decrease, and if the particle diameter is too large, light diffusion in an unnecessary direction may increase.

The particle density (number of particles per square meter) in the matrix resin is preferably about 1.0 × 10 ^{12 to} 1.0 × 10 ¹⁸ from the viewpoint of reducing light absorption by the diffusing material. Preferably it is about 1.0 * 10 < ¹³ > -1.0 * 10 < ¹⁷ >. If the particle density is too low, light may not be diffused efficiently. If the particle density is too high, the amount of light absorbed by the diffusing material may increase.

  The matrix resin and the diffusing material usually have different refractive indexes. For example, the refractive index ratio (Rd / Rm) of the refractive index (Rd) of the diffusing material to the refractive index (Rm) of the matrix resin is 1 About 0.001 to 1.3 is preferable, and about 1.005 to 1.2 is more preferable.

The diffusing member is usually in the form of a sheet, and the thickness thereof may be appropriately set according to the particle diameter, particle density, etc. of the diffusing material, and is preferably about 50 to 1000 μm, and more preferably about 100 to 800 μm.
The diffusing member can be produced by a known method such as molding by mixing a diffusing material uniformly when the matrix resin is kneaded. The diffusion member may be disposed on the light emission side of the light control member via a spacer, or may be integrated by bonding the diffusion member and the light control member.

  In the illuminating device thus obtained, it is possible to reduce the thickness even if it is a direct type. For example, the distance from the bottom of the reflecting member to the light emitting side of the diffusing member is preferably 20 mm or less, more preferably It is 18 mm or less, more preferably 15 mm or less.

(Image display device)
The image display device of the present invention can be obtained by providing a transmissive display element on the light emitting side of the illumination device. For example, by placing a transmissive display element 5 such as a liquid crystal panel on the diffusing member 4 in FIG. 1, a liquid crystal display device having a uniform luminance within the panel display surface can be obtained.

The present invention will be described more specifically with reference to the following examples. However, the present invention is not limited to these examples.

[Example 1]
The reflecting member 1 of the illumination device of the present embodiment has a symmetrical shape with the light source as the center as shown in FIG. The light sources are 12 CCFLs, the distance between the light sources is 18.6 mm, and the distance from the bottom surface of the reflecting member 1 to the light incident side of the light control member 3 is 12 mm. A graph representing the amount of light reaching the light control member 3 is shown in FIG. From this figure, it can be seen that an equal amount of light reaches any place.
FIG. 6 shows the relationship between the position and intensity of the direct light and the reflected light that reach the light control member 3 when only one light source is turned on. As shown in FIG. 6, the reflected light draws a substantially M shape centered directly on the fluorescent tube, and the light incident on the light control member is reflected by the direct light from one light source and the reflecting member. It can be seen that the reflected light is substantially incident on the same place as the adjacent light source. Therefore, the light incident on the light control member is only two light traveling angles reflected by the light reflecting member directly emitted from the fluorescent tube.

  Moreover, the distribution of the diffusion angle by the diffusion member is shown in FIG. As can be seen from FIG. 8, when the direction perpendicular to the main surface is set to 0 °, light entering from the 0 ° direction does not diffuse at angles other than −90 ° to 90 °. Further, FIG. 9 shows the intensity distribution of light traveling in a direction perpendicular to the main surface of the diffusing member and a direction inclined by 45 ° from the vertical.

[Comparative Example 1]
A lighting device was manufactured in the same manner as in Example 1 except that the shape of the reflecting member 1 was a flat surface without the concave portion 11 and the light control member 3 was not used. A graph showing the amount of light reaching the diffusing member 4 is shown in FIG. As is clear from this figure, the light intensity greatly decreased between the light sources, and there was significant luminance unevenness.
As described above, the preferred embodiments of the present invention have been described with reference to the drawings. However, various additions, modifications, or deletions can be made without departing from the spirit of the present invention, and these are also included in the present invention. It is included in the range.

It is a conceptual diagram which shows the cross-sectional structure of one Embodiment of the illuminating device of this invention. It is a conceptual diagram which shows the cross section of the reflection member used in FIG. It is a conceptual diagram which shows the cross-sectional structure of the light control member 3 used in FIG. It is a conceptual diagram which shows the cross-sectional structure of the light control member of the aspect different from FIG. In the illuminating device of Example 1, it is a figure showing the relationship between the position where the direct light and reflected light when all the light sources are turned on reach | attain the light control member 3, and light intensity. In the illuminating device of Example 1, it is a figure showing the relationship between the position and intensity | strength of the direct light which reaches | attains the light control member 3 when only one light source is turned on, and reflected light. In the illuminating device of the comparative example 1, it is a figure showing the relationship between the light intensity and the position where direct light and reflected light when all the light sources are turned on reach the diffusing member 4. In the illuminating device of Example 1, it is a figure which shows the relationship between the diffusion angle of a diffusion member, and intensity | strength. In the illuminating device of Example 1, it is a figure showing the intensity distribution of the light which each advances in the direction perpendicular | vertical with respect to the main surface of a diffusing member after passing through a diffusing member, and the direction inclined 45 degrees from perpendicular | vertical.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Reflective member 2 ... Linear light source 3 ... Light control member 4 ... Diffusion member 5 ... Transmission type display element 7 ... Direct light 8 ... Reflected light 11 ... Concave part 12 ... Connection part 13 ... Projection part 30 ... Projection 31 ... Vertical Surface 32 ... inclined surface

Claims (9)

A plurality of linear light sources arranged in parallel to each other on the same plane, a plurality of concave portions surrounding each linear light source and a reflection member alternately connecting the concave portions, and sandwiching the linear light sources A lighting device comprising: a light control member disposed on the opposite side of the reflecting member; and a diffusion member disposed on the light emitting side of the light control member,
The concave portion of the reflecting member has a symmetrical curved surface with the portion closest to the light source as the center, and the portion closest to the light source has a shape protruding toward the light source,
Incident light incident on the light control member includes direct light directly incident from a single linear light source, and reflected light that is emitted from the linear light source, reflected by the reflecting member, and incident to complement the direct light. And the incident light incident on the light control member from the single linear light source substantially does not include direct light and reflected light from the linear light source adjacent to the linear light source. The lighting device in which the shape of the reflecting member is set.   When reflected light from the plurality of linear light sources is incident on the light control member, the reflected light has a light intensity obtained by continuing a substantially M shape centering directly on the light source facing the light control member in each linear light source. The lighting device according to claim 1.   3. The lighting device according to claim 1, wherein in the reflecting member, the width of the concave portion is 5/6 to 1/1 of the width of the connecting portion.   The lighting device according to any one of claims 1 to 3, wherein the light control member emits 60% or more of incident light by being oriented in a direction perpendicular to a main surface of the light control member.   5. The light control member according to claim 1, wherein the light control member has a plurality of protrusions extending in parallel on at least a light emission surface, and each protrusion has a surface perpendicular to a main surface of the light control member. The lighting device according to item 1.   The lighting device according to claim 1, wherein a backscattering probability by the diffusing member is 10% or less.   The illuminating device according to any one of claims 1 to 6, wherein in the diffusing member, diffusing particles having a refractive index different from that of the matrix resin are dispersed in a transparent matrix resin.   The illuminating device according to any one of claims 1 to 7, wherein a distance from a bottom portion of the reflecting member to a light emitting side of the diffusing member is 20 mm or less.   The image display apparatus which provided the transmission type display element in the light-projection side of the illuminating device of any one of Claims 1-8.

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