KR20100020744A - Light guide and two branch line shape light source - Google Patents

Abstract

PURPOSE: A light guide and a two branch linear light source are provided to input light to an optical emission surface by converging the reflected light from a reflective surface by forming the reflective surface with a concave shape in a width direction of the light guide. CONSTITUTION: A light emission surface(5a,5b) opposite to a reflective surface(4a,4b) is formed on a light guide(1) with a transparent rod shape. The light guide is generated by the incident light from an LED. The reflective surface is extended to a length direction. The reflective surface is comprised of two surfaces crossing the vertical surface extended to the length direction of the reflective surface. A pair of protrusions(6a,6b) are installed on a side between the reflective surface and the light emission surface. The light emission surface is comprised of the common surface.

Description

LIGHT GUIDE AND TWO BRANCH LINE SHAPE LIGHT SOURCE}

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a light guide and a two-branch linear light source device, and in particular, to a light guide and a two-branch linear light source device used as an illuminating light source of an image reading device used in a facsimile, copier, image scanner, bar code reader, and the like. It is about.

In recent years, in an image reading apparatus such as a personal facsimile, a small and low power LED is used as a light source of a reading light source device by improving the output of a light emitting diode (hereinafter referred to as LED) and increasing the sensitivity of a CCD sensor as a light receiving element. To be used. The conventional linear light source device equipped with such an LED as a light source aims to reduce the number of light sources and to obtain a uniform illumination intensity, and allows the light emitted from the light source to enter the light guide using a light guide. It is known to guide light in a desired direction.

Patent Document 1 describes a light guide member having an inverted V-shaped light deflection surface at a position facing the light exit surface in the cross-sectional shape of the light guide body in the width direction. Since the light exit surface has a smaller curvature than the other parts, it is described that light emitted from the light exit surface is focused, for example, light having directivity to the original surface is irradiated.

Further, Patent Document 2 discloses a light-side surface in a cross-sectional shape in the width direction of the light guide, wherein the light exit surface is formed in the shape of a lens surface having a shape such as an arc or an ellipse, and opposes the light exit surface. The light guide body provided with two facing surfaces is described.

In addition, Patent Document 3 describes a light source device in which two sets are arranged so that an illumination unit equipped with a light source is opposite to one end surface of the light guide. The light guide is comprised of resin with high light transmittance, such as acryl and polycarbonate, or optical glass with high light transmittance, and the light emission surface is formed in one side surface. The light source includes, for example, one or a plurality of surface mount LEDs mounted thereon, and the light incident on the one end surface of the light guide from the LED is guided in the longitudinal direction while reflecting from the inner surface of the light guide, and from the light exit surface. It is comprised so that light may be emitted in the direction of an arrow. Each illumination unit is described in which light emitted from such a light exit surface is disposed so as to irradiate the original reading surface of the original surface so as to irradiate the original reading surface of each of the same areas.

[Patent Document 1: Japanese Patent Laid-Open No. 2001-159796]

[Patent Document 2: Japanese Patent Application Laid-Open No. 2000-59571]

[Patent Document 3: Japanese Patent Laid-Open No. 2005-229647]

However, since the light guide body of patent document 1 and patent document 2 irradiates light to a document reading surface from 1 direction, a shadow will arise if there are a flap and the step part by bonding to the paper surface to be irradiated. In addition, since the light source device described in Patent Document 3 is configured to irradiate light onto the document reading surface from two directions, even if there are a fold or a stepped portion due to bonding, no shadow is generated, but two light guides are arranged. As a result, the whole apparatus becomes large and cannot respond to the request for downsizing.

DISCLOSURE OF THE INVENTION In view of the above problems, an object of the present invention is to provide a light guide and a two-branch linear light source device that can irradiate light onto the document reading surface from two directions and realize miniaturization of the device. .

MEANS TO SOLVE THE PROBLEM This invention employ | adopts the following means in order to solve said subject.

The first means is a transparent rod-shaped light guide member having a light deflecting surface extending in a longitudinal direction and a light exiting surface opposing the light deflecting surface, wherein the light deflecting surface intersects a vertical plane extending in the longitudinal direction with respect to the light deflecting surface. It is a light guide body formed from two surfaces arrange | positioned.

The second means comprises, in the first means, an intersection angle formed by the intersection of the vertical planes with θ1, two intersection lines where each vertical plane intersects the light exit plane, and a curvature center line on the light exit plane side. When the angle is θ2, the light guide is characterized by having a relationship of θ1 ≧ θ2.

The third means is the light guide according to the first means or the second means, wherein each of the light deflecting surfaces is formed in a concave shape with respect to the width direction of the light guide.

The fourth means is a transparent rod-shaped light guide member having a light deflecting surface extending in a longitudinal direction and a light exit surface facing the light deflection surface, wherein the light exit surface is formed of two curved surfaces having the same or different curvature. It is a light guide characterized by the above-mentioned.

The fifth means includes an LED, a light guide formed of a transparent rod-like body and generated by light incident from the LED, and emitting light in two directions from a longitudinal side surface of the rod-shaped body, and one of the two directions. A bi-branch linear light source device, comprising: a reflector reflecting light toward the other side of the light in the two directions.

The sixth means includes a light guide member according to any one of the first to fourth means, a light source provided to face the light incidence portion provided on at least one of both ends in the longitudinal direction of the light guide member, and the light of the light guide member. It has the same length as the emitting surface and is installed at a position substantially symmetrical with the light emitting surface with respect to the surface perpendicular to the center of the original reading surface, and the light in one of two directions emitted from the light emitting surface is different from the other of the two directions. A bi-branch linear light source device, comprising: a reflector reflecting toward a direction of light on the side.

According to the invention as set forth in claim 1, since the light deflecting surface of the light guide is formed of two faces arranged so as to intersect the vertical plane extending in the longitudinal direction with respect to the light deflecting surface, it is possible to emit light in two directions from one light guide. In the case where the light guide is applied to the light source device, light from two directions can be easily irradiated to the original reading surface.

According to the invention according to claim 2, the intersection angle formed by the intersection of the vertical planes extending in the longitudinal direction with respect to each light deflection surface of the light guide is θ1, and the two intersection lines where each vertical plane crosses the light exit plane and the curvature center line on the light exit plane side. When the angle formed by θ2 is θ2, the angle area of the light exit surface becomes small, and the angle of each light emitted from the light exit surface becomes large. And the formation area of the light exit surface can be narrowed, the degree of freedom in design at the time of shape design increases, and the formation of the projection for reinforcing the light guide can be facilitated, and the light guide can be easily fixed to the light source device.

According to the invention as set forth in claim 3, since each light deflection surface of the light guide is formed in a concave shape with respect to the width direction of the light guide, the light deflected from the light deflection surface can be converged and incident on the light exit surface. Irrespective of the shape of the surface, light emitted in two directions from the light exit surface can be converged and emitted.

According to the invention as set forth in claim 4, since the light exit surface of the light guide is formed of two curved surfaces having the same curvature or the other, it is preferable to converge the light exiting in two directions from the light exit surface in an arbitrary direction. It becomes easy.

According to the invention of claim 5, the two-branch linear light source device is formed of an LED and a transparent rod-shaped light guide, which is generated by light incident from the LED, and emits light in two directions from the longitudinal side surface of the rod-shaped body. By constructing a sieve and a reflector reflecting one light in two directions to the direction of the other light in the two directions, the configuration for irradiating light from the two directions to the original reading surface becomes easy, and only one light guide is used. As a result, the device can be miniaturized.

According to the invention of claim 6, the two-branch linear light source device is provided to face the light guide member according to any one of claims 1 to 4 and the light incidence portions provided on at least one of both ends of the light guide body in the longitudinal direction. The light source has the same length as the light exit plane of the light guide and is disposed at a position substantially symmetrical with the light exit plane with respect to the plane perpendicular to the center of the original reading plane, and emits light in one of two directions emitted from the light exit plane. By constructing a reflector reflecting toward the other side of the light in the two directions, the configuration for irradiating light from the two directions to the original reading surface becomes easy, and since only one light guide is used, the device can be miniaturized.

1st Embodiment of this invention is described using FIGS.

1 is a perspective view of a light guide 1 according to the invention of the present embodiment.

In Fig. 1, 1 is a light guide, 2 is a light incident surface formed on one end surface in the longitudinal direction of the light guide 1, 3 is the other end surface in the longitudinal direction of the light guide 1, 4a, 4b is a light deflection surface ( Reflecting surface), 5a and 5b are light exit surfaces, and 6a and 6b are pairs of projections provided on side surfaces between the light deflection surfaces 4a and 4b and the light exit surfaces 5a and 5b.

The light guide 1 consists of rod-shaped transparent acrylic resin, the radius is formed into the thin rod shape of phi 5-6, 320 mm in length, and a pair of projection part 6a, 6b is a light guide ( Since only the both ends of 1) are hold | maintained, the light guide 1 bends and an illumination position shifts, and it is provided in order to make fixed holding easy. The light guide 1 is provided with a light incidence surface 2 on at least one longitudinal end face, and a first light deflection surface 4a and a second light deflection surface 4b are formed on one side surface extending in the longitudinal direction. The first light deflection surface 4a and the second light deflection surface 4b are formed such that the vertical planes extending in the longitudinal direction with respect to the first light deflection surface 4a and the second light deflection surface 4b intersect. Moreover, the light exit surface 5a, 5b is formed in the other side surface extended in the longitudinal direction of the light guide 1 facing the 1st light deflection surface 4a and the 2nd light deflection surface 4b. The light exit surfaces 5a and 5b are formed in a common plane and the cross section is substantially semicircular.

FIG. 2 shows the light guide 1 having the first light deflecting surface 4a and the second light deflecting surface 4b shown in FIG. 1 in one end surface in the longitudinal direction, that is, in the light incident surface 2 or in the longitudinal direction. It is the projection figure seen from the other end surface 3. As shown in FIG.

In this projection view, the first light deflection surface 4a and the second light deflection surface 4b are shown as line segments 4a and 4b. The line perpendicular | vertical with respect to the 1st light deflection surface 4a shown as a line segment in a projection view, and advancing toward the light deflection surface 5a from the center of the 1st light deflection surface 4a is made into the 1st vertical line 15a. In this manner, a line perpendicular to the second light deflection surface 4b shown as a line segment in the projection view and traveling from the center of the second light deflection surface 4b toward the light deflection surface 5b is referred to as the second vertical line 15b. do. These two vertical lines, the first vertical line 15a and the second vertical line 15b intersect at an intersecting angle θ1. In addition, the 1st vertical line 15a and the 2nd vertical line 15b are a surface extended in a longitudinal direction when seen from the perspective view shown in FIG. The virtual plane which extends in the longitudinal direction of the light guide 1 including this 1st vertical line 15a or the 2nd vertical line 15b is called "a vertical plane extended in the longitudinal direction with respect to a light deflecting surface."

As the first light deflection surface 4a and the second light deflection surface 4b are formed in parallel in the longitudinal direction with a large number of ridges and grooves in the longitudinal direction, as shown in the first light deflection surface 4a in FIG. By forming the 4a and the second light deflecting surface 4b on a plane, processing of a mold or the like used when the light guide 1 is produced by injection molding is facilitated. Moreover, the 1st light deflection surface 4a and the 2nd light deflection surface 4b are formed in the planar shape of the width direction 0.5 mm-2 mm, for example, 1 mm width, and the intersection angle (theta) 1 is 45 ° to 65 °, for example, 55 ° away from each other. In addition, in the 1st light deflection surface 4a and the 2nd light deflection surface 4b, the 1st vertical line 15a and the 2nd vertical line 15b are semi-circular on the light exit surface 5a, 5b side of the light guide 1, In addition to being installed so as to intersect at the curvature center line, it is disposed farther than the radius of the semi-circular shape to improve the convergence of the emitted light from the light exit surfaces 5a and 5b.

In the first light deflection surface 4a and the second light deflection surface 4b, since a large number of ridge-shaped grooves are formed in parallel in the longitudinal direction, the light incident from the light incidence surface 2 is internal to the light guide 1. While total reflection is repeated, light is efficiently guided in the longitudinal direction of the light guide 1, that is, the other end surface 3 direction. The light of the angular component of the guided longitudinal direction is directed to the light exit surface 5a and the light exit surface 5b facing each other by the first light deflection surface 4a and the second light deflection surface 4b. Direction), and is emitted from the light exit surface 5a and the light exit surface 5b according to Snell's law.

FIG. 3 is a cross-sectional view of the light guide 1 shown in FIG. 1 taken along a longitudinal direction from the center of the first light deflection surface 4a.

In FIG. 3, 7 is a light source which consists of LEDs. The light source 7 is disposed in the direction of irradiating light to the light incident part 2 formed at one end in the longitudinal direction of the light guide 1, and the light source 7 and the light guide 1 are separated from each other at an extremely close distance. The light emitted from the light source 7 is emitted into the atmosphere, and then enters the inside of the light guide 1.

Light incident on the light guide 1 from the light source 7 totally reflects the inside of the light guide 1 and is guided in the longitudinal direction X. FIG. In the process of being guided, the light incident on the inclined grooves of the mountain-shaped concave-convex grooves of the light deflecting surface 4a is redirected to the short side (width) direction Y of the light guide 1 and is emitted from the light exit surface 5a. . Since the angled uneven groove inclined surface of the light deflecting surface 4a is angled so that the light A1 from the light source 7 becomes light A2 that radiates in a direction substantially perpendicular to the light exit surface 5a, Light A1 incident on the uneven groove inclined surface of the light deflecting surface 4a travels in the width direction Y of the light guide 1 directed from the light deflecting surface 4a to the light exit surface 5a. Becomes Further, the light B1 incident on the light exit surface 5a from the light source 7 is totally reflected at the light exit surface 5a, and the light B2 proceeds in the longitudinal direction X while having the angle of incidence angle. do. Thereafter, the reflected light B2 is incident on the inclined surface of the uneven groove of the light deflecting surface 4a and is directed to the short side (width) of the light guide 1 from the light deflecting surface 4a to the light exit surface 5a. Light B3 proceeds to (Y).

As shown in FIG. 3, the vertex spacing of the mountain-shaped uneven groove of the light deflection surface 4a is formed so as to be wider on the side near the light source 7 and narrow on the far side. That is, the vertex spacing of the mountain-shaped uneven groove of the light deflection surface 4a is adjusted to be smaller as it moves away from the light source 7. By configuring in this way, the probability of changing the light incident from the light source 7 can be fixed or arbitrarily, and a desired illuminance distribution can be obtained. Moreover, although not shown, the film of aluminum is provided in the light guide 1 outer surface of the part in which the light deflection surface 4a was formed. The aluminum film functions as a reflective film, prevents light from exiting from the light deflecting surface 4a to the outside of the light guide 1, efficiently irradiates the side to be illuminated, and prevents stray light.

4 and 5 are perspective views showing a part of the two-branch linear light source device to which the light guide 1 shown in FIGS. 1 to 3 are applied, and a two-branch line shape cut along the width direction of the light guide 1, respectively. It is sectional drawing of a light source device.

In these figures, 8 is a reflector disposed at a position substantially symmetrical with the light guide 1 with respect to the plane perpendicular to the center of the original reading surface 9, 9 is the original reading surface, 10 is the case, 11 is the light guide. The holding portion formed in a substantially U-shape for fixing (1), the support portion formed in a substantially U-shape for fixing the light guide 1, extending from the bottom surface, and 13 and 14 are installed in the case 10 to pass through the light. It is a transparent window. In addition, the other structure corresponds to the structure of the same code | symbol shown in FIG.

The reflecting mirror 8 is composed of a groove-shaped mirror having the same length as the length in the longitudinal direction of the first light deflecting surface 4a and the second light deflecting surface 4b, for example, a bright aluminum plate or An aluminum film is formed on the reflection surface, and the shape is formed in elliptical cross section or parabolic cross section. By configuring in this way, the direction of the light emitted from the light exit surface 5b of the light guide 1 can be changed and guided to the document reading surface 9. Reflector 8 takes approximately all of the light emitted from second light exit surface 5b of light guide 1 and reaches the bottom surface from the top surface of case 10 to reflect toward original reading surface 9. Has the size of. In addition, it is preferable that the light guide 1 side be the window 14 from the reflecting mirror 8 of the case 10 so as not to block the reflected light. In addition, the light guide 1 and the reflector 8 are fixed to the case 10. In addition, the pair of projections 6a and 6b are sandwiched between the holding portion 11 and the supporting portion 12 so as to be fixed and held so as not to rotate. By holding and holding the light guide 1 in this way, it can be easily attached to an apparatus, without using an adhesive agent.

Since the light guide 1 and the light source 7 are spaced apart from each other, the light entering the light guide 1 has a refractive index of about 1.5 even when the light guide 1 is close to the incident angle 90. After the incident (inside the light guide), the angle exceeds the critical angle 42 ° with respect to the side surface of the light guide 1. Therefore, there is no light directly exiting from the side surface of the light guide 1, and all of the light incident on the light guide 1 from the light source 7 becomes totally reflected light. Light incident on the light guide 1 passes through the light guide 1 and is reflected by the first light redirecting surface 4a and the second light redirecting surface 4b, respectively, in two directions from the light exit surfaces 5a and 5b. Is emitted as the light P, Q, and the reflected light R reflected by the direct light P and light Q by the reflector 8 is irradiated onto the document reading surface 9.

A second embodiment of the present invention will be described with reference to FIGS. 6 and 7.

6 and 7 (a) show one end surface of the light guide 1 having the first light deflecting surface 4a and the second light deflecting surface 4b according to the invention of the present embodiment, that is, light. 7 (b) shows a light incident surface of the light guide 1 to be contrasted with the light guide 1 shown in FIG. 7 (a). 2) or the projection view seen from the other end surface 3 in the longitudinal direction. In addition, the structure of the code | symbol shown by these figures corresponds to the structure of the same code | symbol shown in FIG.

In the projection diagram shown in FIG. 6, the 1st light deflection surface 4a and the 2nd light deflection surface 4b are shown as the line segments 4a and 4b. The line perpendicular | vertical with respect to the 1st light deflection surface 4a shown as a line segment in a projection diagram, and advancing toward the light deflection surface 5a from the center of the 1st light deflection surface 4a is made into the 1st vertical line 15a. Thus, the line perpendicular | vertical with respect to the 2nd light direction surface 4b shown as a line segment in a projection view, and advancing toward the light direction surface 5 from the center of the 2nd light direction surface 4b is the 2nd vertical line 15b. It is done. These two vertical lines, the first vertical line 15a and the second vertical line 15b intersect at an intersecting angle θ1. The virtual plane which extends in the longitudinal direction of the light guide 1 including this 1st vertical line 15a or the 2nd vertical line 15b is called "a vertical plane extended in the longitudinal direction with respect to a light deflecting surface."

The first light deflection surface 4a and the second light deflection surface 4b are spaced apart from each other such that the length in the width direction is, for example, a planar shape with a width of 1 mm, and the crossing angle θ1 is 55 °. Placed and placed. Further, the first light deflection surface 4a and the second light deflection surface 4b, the first vertical line 15a and the second vertical line 15b are circular on the light exit surfaces 5a and 5b side of the light guide 1. It is installed to cross at the center of curvature.

In FIG. 6, light incident from the light incidence plane 2 (not shown) of the light guide 1 from the light source 7 (not shown) repeats total reflection through the inside of the light guide 1. It is guided efficiently in the longitudinal direction of 1). The light of the angular component of the guided longitudinal direction is directed to the light exit surface 5a and the light exit surface 5b facing each other by the first light deflection surface 4a and the second light deflection surface 4b. Direction), and exits from the light exit surface 5a and the light exit surface 5b according to Snell's law. For example, since the light beam A1 deflected by the light deflecting surface 4a passes through the center of the light guide 1 (the center of the light guide 1), the light exit surface 5a does not change the angle. It is emitted. Further, the light rays b1 and c1, which are widened at an arbitrary angle θ with respect to the vertical plane of the light deflection surface 4a, enter the light exit surface 5a at an angle of incidence θ, and according to Snell's law, the normal of the incident surface about,

θ '= Sin (NSinθ) ^-1

Is radiated at an angle of. Here, N is the refractive index of the light guide 1. Therefore, by adjusting the curvature of the light exit surface 5a and the distance between the light deflection plane 4a and the center of curvature of the light exit surface 5a, light widening at an arbitrary angle θ is converged and irradiated in the same direction. It becomes possible. In the light guide 1 shown in FIG. 6, since the first vertical line 15a and the second vertical line 15b intersect at the central axis of the radius of curvature of the light exit surfaces 5a and 5b, the first vertical line 15a is provided. The light converges from the light exit surfaces 5a and 5b and exits in the same direction as the second vertical line 15b.

The light guide 1 shown to FIG. 7 (a) and FIG. 7 (b) has the same projection as the light guide 1 shown in FIG. The line perpendicular | vertical with respect to the 1st light deflection surface 4a shown as a line segment in a projection diagram, and advancing toward the light deflection surface 5a from the center of the 1st light deflection surface 4a is made into the 1st vertical line 15a. In this way, a line perpendicular to the second light deflection surface 4b indicated as the line segment in the projection view and traveling from the center of the second light deflection surface 4b toward the light deflection surface 5b is referred to as the second vertical line 15b. do. These two vertical lines, the first vertical line 15a and the second vertical line 15 intersect at an intersecting angle θ1. The virtual plane which includes this 1st vertical line 15a or the 2nd vertical line 15b, and extends in the longitudinal direction of the light guide 1 is called "a vertical plane extended in the longitudinal direction with respect to a light deflecting surface."

In the light guide 1 shown in FIG. 7A, the first vertical line 15a and the second vertical line 15b intersect the outer side of the central axis of the cylindrical light guide 1, but are not shown in FIG. 7B. In the light guide 1 shown, "the 1st vertical line 15a and the 2nd vertical line 15b intersect inside the central axis of the cylindrical light guide 1. As shown in FIG. That is, in the light guide 1 shown in Fig. 7A, a vertical line including the first vertical line 15a and a vertical plane including the second vertical line 15b intersect the light exit surfaces 5a and 5b. The angle θ2 formed by the normal at is smaller than the crossing angle θ1 at which the first vertical line 15a and the second vertical line 15b intersect. On the other hand, in the light guide 1 shown in FIG. 7B, the vertical plane including the first vertical line 15 and the vertical plane including the second vertical line 15b intersect with the light exit surfaces 5a and 5b. The angle θ2 formed by the normal to the line is larger than the crossing angle θ1 at which the first vertical line 15a and the second vertical line 15b intersect.

In the light guide 1 shown in Fig. 7A, the angle regions of the light exit surfaces 5a and 5b are the angles of the light exit surfaces 5a and 5b of the light guide 1 shown in Fig. 7B. It becomes smaller than the area. In addition, in the light guide 1 shown to Fig.7 (a), the angle of each light radiate | emitted from the light emission surface 5a, 5b becomes large compared with the thing of the light guide 1 of FIG.7 (b). Therefore, as in the light guide 1 shown in Fig. 7A, by making the angle θ2 smaller than the angle θ1, the first light deflection surface 4a, the second light deflection surface 4b, and the light exit surface ( The formation area of 5a, 5b can be narrowed, the freedom of design at the time of shape design can be increased, and manufacture of the projection part 6a, 6b, the holding part 11, the support part 12, etc. as shown in FIG. This is facilitated.

A third embodiment of the present invention will be described with reference to FIG. 8.

FIG. 8: is a projection view which looked at the light guide 1 which has the 1st light deflection surface 4a and the 2nd light deflection surface 4b of the light guide 1 which concerns on FIG. 8, this invention from the cross section in the longitudinal direction. In addition, the structure of the code | symbol shown in such a figure corresponds to the structure of the same code | symbol shown in FIG.

The line perpendicular | vertical with respect to the 1st light deflection surface 4a shown as a line segment in a projection diagram, and advancing toward the light deflection surface 5a from the center of the 1st light deflection surface 4a is made into the 1st vertical line 15a. In this way, the line perpendicular to the second light deflection surface 4b indicated as the line segment in the projection view and traveling from the center of the second light deflection surface 4b toward the light deflection surface 5b is the second vertical line 15b. It is done. These two vertical lines, the first vertical line 15a and the second vertical line 15b intersect at an intersecting angle θ1. The virtual plane which includes this 1st vertical line 15a or the 2nd vertical line 15b, and extends in the longitudinal direction of the light guide 1 is called "a vertical plane extended in the longitudinal direction with respect to the light deflecting surface."

As shown in FIG. 8, the 1st light deflection surface 4a and the 2nd light deflection surface 4b are formed in one common semicircle, and the light exit surface 5a and the light exit surface 5b are common to the other. Is formed in a semicircular shape, and the two semicircular shapes are connected in a plane, and the first light deflection surface 4a and the second light deflection surface 4b are farther than one common semi-circular radius of the light exit surfaces 5a and 5b. It is placed in place. By configuring in this way, the convergence property of the emission light from the light emission surface 5a, 5b can be improved.

A fourth embodiment of the present invention will be described with reference to FIG.

FIG. 9A is an enlarged view of the first light deflecting surface 4a and the second light deflecting surface 4b of the light guide 1 shown in FIGS. 9B to 9D, and FIG. 9B is a light emitting surface ( Projection view seen from one end surface of the light guide 1 which concerns on invention of this embodiment which has a planar part in 5a, 5b), FIG.9 (c) is a part of light output surface 5a, 5b. Fig. 9 (d) is a projection view seen from one end face in the longitudinal direction of the light guide 1 according to the invention of the present embodiment having two inwardly facing planar portions, in part of the light exit surfaces 5a and 5b. It is a projection view seen from the one cross section of the longitudinal direction of the light guide 1 which concerns on invention of this embodiment which has two outwardly planar parts. In addition, the structure of the code | symbol shown in such a figure corresponds to the structure of the same code | symbol shown in FIG.

As shown in Fig. 9 (a), the first light deflection surface 4a and the second light deflection surface 4b of the light guide 1 shown in Figs. It is formed in a concave shape with respect to the radial direction. By such a configuration, for example, the light a1 to c1 emitted from the first light deflection surface 4a can be converged and incident on the light exit surface 5a. 9 (b) to 9 (c), by forming a part of the light exit surfaces 5a and 5b in a planar shape, the convergence of the emitted light from the light exit surfaces 5a and 5b is slightly increased. Although sacrificed, the luminous flux and direction of the emitted light from the light exit surfaces 5a and 5b can be arbitrarily controlled.

5th Embodiment of this invention is described using FIG.

FIG. 10 shows the light guide 1 according to the invention of the present embodiment having one light deflecting surface 4 and a cross section in which the light output surface 5a and the light output surface 5b are independent in a substantially semicircular shape. This is a projection view seen from one cross section in the longitudinal direction of.

In FIG. 10, 4 is one light deflecting surface which extends in the longitudinal direction to the side surface of the light guide 1, and the other structure corresponds to the structure of the same code | symbol shown in FIG.

As shown in FIG. 10, 16a is a normal line of the light emission surface 5a, and 16b is a normal line of the light emission surface 5b. The light guide 1 is composed of two curved surfaces formed in a substantially semicircular shape in which the normal lines 16a and 16b have different angles, the light output surface 5a and the light output surface 5b. With this configuration, the light which is changed from one light deflecting surface 4 and incident on the light exiting surfaces 5a and 5b is respectively formed by the light exiting surface 5a and the light exiting surface 5b each formed in a substantially semicircular shape. They can converge independently and emit in different directions.

A sixth embodiment of the present invention will be described with reference to FIG.

FIG. 11A shows the present embodiment having a first light deflecting surface 4a and a second light deflecting surface 4b, each having a light exiting surface 5a and a light exiting surface 5b each having an independent cross section in a substantially semicircular shape. Fig. 11 (b) is a projection view seen from one end face in the longitudinal direction of the light guide 1 according to the invention of the form, and FIG. 11 (b) shows the light guide 1 to be contrasted with the light guide 1 shown in Fig. 11 (a). It is a projection view seen from the cross section in the longitudinal direction. In addition, the structure of the code | symbol shown in such a figure corresponds to the structure of the same code | symbol shown in FIG.

A line perpendicular to the first light deflection surface 4a shown as a line segment in the projection diagram and traveling toward the light deflection surface 5b from the center of the first light deflection surface 4a is referred to as the first vertical line 15a. . In this manner, a line perpendicular to the second light deflection surface 4b indicated as the line segment in the projection view and traveling from the center of the second light deflection surface 4b toward the light deflection surface 5a is referred to as the second vertical line 15b. do. These two vertical lines, the first vertical line 15a and the second vertical line 15b intersect at an intersecting angle θ1. The virtual plane which extends in the longitudinal direction of the light guide 1 including this 1st vertical line 15a or the 2nd vertical line 15b is called "a vertical plane extended in the longitudinal direction with respect to a light deflecting surface."

In the light guide 1 shown in Figs. 11A and 11B, the normal 16a of the light exit surface 5a and the normal 16b of the light exit surface 5b have substantially different angles. It consists of two curved surfaces formed in semicircle shape, the light output surface 5a and the light output surface 5b, and differ in the direction of the 1st vertical line 15a and the 2nd vertical line 15b.

In the light guide 1 shown in FIG. 11A, the vertical plane including the first vertical line 15a and the vertical plane including the second vertical line 15b intersect with the light exit surfaces 5a and 6b. The angle θ2 formed by the normal line is approximately equal to the crossing angle θ1 at which the first vertical line 15a and the second vertical line 15b intersect. On the other hand, in the light guide 1 shown in FIG. 11B, the vertical plane including the first vertical line 15a and the vertical plane including the second vertical line 15b intersect with the light exit surfaces 5a and 5b. The angle θ2 formed by the normal to the line is larger than the crossing angle θ1 at which the first vertical line 15a and the second vertical line 15b intersect.

In the light guide 1 shown in Fig. 11A, the angular areas of the light exit faces 5a and 5b are the angle areas of the light exit faces 5a and 5b of the light guide 1 shown in Fig. 11B. It becomes smaller than. In addition, in the light guide 1 shown to Fig.11 (a), the angle of the light radiate | emitted from the light emission surface 5a, 5b becomes large compared with the thing of the light guide 1 of FIG. 11 (b). Therefore, as in the light guide 1 shown in Fig. 11A, by making the angle θ2 equal to or smaller than the angle θ1, the first light deflection surface 4a, the second light deflection surface 4b, and the light are The formation area | region of emission surface 5a, 5b can be narrowed, and the freedom of design at the time of shape design can be increased.

1 is a perspective view of a light guide 1 according to the invention of the first embodiment.

FIG. 2 is a projection view seen from one cross section in the longitudinal direction of the light guide 1 shown in FIG. 1.

FIG. 3 is a cross-sectional view of the light guide 1 shown in FIG. 1 taken along a longitudinal direction from the center of the first light deflection surface 4a.

4 is a perspective view showing a part of a bi-branch linear light source device to which the light guide 1 shown in FIGS. 1 to 3 is applied.

FIG. 5 is a cross-sectional view of the bi-branch linear light source device cut along the width direction of the light guide 1 shown in FIGS. 1 to 3.

6 is a projection view seen from one cross section in the longitudinal direction of the light guide 1 according to the invention of the second embodiment.

7 is a projection view seen in one cross section in the longitudinal direction of the light guide 1 according to the invention of the second embodiment, and a light guide 1 for contrast with the light guide 1 according to the invention of the present embodiment. It is a projection view seen from the cross section in the longitudinal direction.

8 is a projection view seen from one cross section in the longitudinal direction of the light guide 1 according to the invention of the third embodiment.

9 is an enlarged view of the first light deflecting surface 4a and the second light deflecting surface 4b of the light guide 1 according to the invention of the fourth embodiment, and the light guide 1 according to the invention of the present embodiment. This is a projection view seen from one cross section in the longitudinal direction of.

FIG. 10 is a projection view seen from one cross section in the longitudinal direction of the light guide 1 according to the invention of the fifth embodiment. FIG.

11 is a projection view seen from one end face in the longitudinal direction of the light guide 1 according to the invention of the sixth embodiment, and a light guide 1 for contrast with the light guide 1 according to the invention of the present embodiment. It is a projection view seen from the cross section in the longitudinal direction.

[Description of the code]

1 light guide

2 light incident

3 other cross section

4, 4a, 4b light deflecting surface (reflective surface)

5a, 5b light exit

6a, 6b protrusions

7 light source

8 reflector

9 Original Reading Surface

10 cases

11 Maintenance

12 support

13, 14 windows

Claims (6)

In the transparent rod-shaped light guide body in which the light-deflecting surface extended in the longitudinal direction and the light output surface which opposes the light-deflecting surface are formed, And the light deflecting surface is formed of two faces arranged such that a vertical plane extending in the longitudinal direction with respect to the light deflecting surface intersects. The method according to claim 1, When the intersection angle formed by the intersection of the vertical planes is θ1, and the angle formed by the two intersection lines where each vertical plane intersects the light exit plane and the curvature center line on the light exit plane side is θ2, the relationship is θ1≥θ2. The light guide body which has it. The method according to claim 1 or 2, Each said light deflecting surface is formed in concave shape with respect to the width direction of a light guide body, The light guide body characterized by the above-mentioned. In the transparent rod-shaped light guide body in which the light-deflecting surface extended in the longitudinal direction and the light output surface which opposes the light-deflecting surface are formed, The light guide surface is formed of two curved surfaces having the same curvature or different curvatures. The light guide body is formed of an LED, a transparent rod-shaped body and is emitted by light incident from the LED, and emits light in two directions from a longitudinal side surface of the rod-shaped body; A bi-branch linear light source device, comprising: a reflector reflecting toward the direction of the other light in the direction. The light guide body of any one of Claims 1-4, the light source provided opposing the light incident part provided in at least one of the longitudinal direction both ends of the light guide body, and has the same length as the light exit surface of the said light guide body. And a position substantially symmetrical with the light exit plane with respect to a plane perpendicular to the center of the original reading surface, and reflects one of the two directions of light emitted from the light exit surface to the direction of the other of the two directions. A two-branch linear light source device comprising a reflector.

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