JP2014120378A - Portable type inclined illumination apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a portable inclined illumination apparatus superior in energy saving and capable of obtaining illumination efficient and suitable for makeup.SOLUTION: A portable oblique illumination device U does not dazzle use's eyes even if the illumination device is placed faceup on a desk because of directional surface emission illumination. Owing to this, even with a user holding a mirror MR opposite to a user face UF, the mirror MR does not obstruct the illumination since the user's face UF is illuminated from obliquely downward. Furthermore, the entire user's face UF can be illuminated without casting a shadow on the user's face UF.

Description

  The present invention relates to a lighting device, and more particularly to a portable oblique lighting device that can efficiently illuminate a person.

  In general, people often make makeup while looking in the mirror, but it is known from experience that the finish of makeup varies greatly depending on the lighting environment. However, in recent years, there have been opportunities to apply makeup regardless of location, such as on the table of a coffee shop, in the middle of work or in the bathroom, etc. In order to ensure that the makeup finish is satisfactory, ensure a predetermined lighting environment. There is a need to. However, it is impossible to walk with a large lighting device, and there is a fact that those who make up make the best efforts in a limited lighting environment.

  Patent Document 1 discloses a portable planar lighting device that can be stored in a wallet, a handbag, a decorative case, and the like and is suitable for carrying.

JP 2007-335227 A JP 09-262134 A

  However, the planar illumination device of Patent Document 1 is configured so that the thickness of the light guide plate increases as the distance from the light source increases in order to emit planar light with high emission efficiency and no luminance unevenness. Since the thickness of the light guide plate is increased in accordance with the thickness of the light guide plate and is relatively bulky, there is a problem that a large space is required when it is put in a handbag or the like. In addition, since the light emitted from the surface illumination device spreads over the entire area, useless light is emitted in addition to the necessary parts. Therefore, when trying to obtain the illuminance necessary for makeup, the battery decreases quickly. There is a problem of becoming.

  On the other hand, Patent Document 2 discloses a technique in which a lighting device is attached to a part of a portable device with a mirror, and the lighting device can be turned on and off by a switch ON and OFF. However, in such a conventional technique, since the illumination device is provided around the mirror, there is a problem that the illumination light easily enters the eyes of the user viewing the mirror and feels dazzling. On the other hand, if the angle of the mirror is changed in order to suppress glare, there is a problem that illumination light strikes a place other than his / her face, and illumination suitable for makeup cannot be obtained.

  The present invention has been made in view of the above circumstances, and provides a portable oblique illumination device that is thin and convenient for carrying, can save energy, is highly efficient, and can provide illumination suitable for makeup. The purpose is to do.

The portable oblique illumination device according to claim 1 is:
A light source having a plurality of light emitting points having a color rendering property of Ra80 or higher,
An incident surface on which light emitted from the light source is incident, a first main surface from which incident light is emitted, a second main surface disposed opposite to the first main surface and substantially parallel to the first main surface, and the first main surface Or a light guide plate provided with optical path deflecting means provided on the second main surface;
A housing that houses the light source and the light guide plate;
A portable oblique illumination device having a drive circuit for supplying a current from a battery to the light source,

After the light from the light source is incident from the incident surface, the light is guided between the first main surface and the second main surface, and through the optical path deflecting unit, the light from the first main surface. The angle θmax formed between the normal line of the first main surface and the direction of the maximum luminance peak of the emitted light satisfies 15 ° <θmax <60 °.

  According to the present invention, the angle θmax formed between the normal line of the first main surface and the direction of the maximum luminance peak of the emitted light satisfies 15 ° <θmax <60 °, so that the first emission surface faces upward. For example, when the portable oblique illumination device is placed near the hand on the desk, the maximum luminance peak direction of the emitted light is directed to the vicinity of the face of the user in front of the desk, so that it is difficult to make a shadow on the face. Can illuminate the entire face. In particular, since a high color rendering light source of Ra80 or higher is used, it is possible to emit illumination light close to natural light, so by using the portable oblique illumination device at the time of makeup, even under a fluorescent lamp with poor color rendering properties, A situation close to natural light can be realized, and the finish of the makeup can be made good. Furthermore, even when applying makeup with a strong eye color such as eye makeup or teak, the face is illuminated with the mirror close to it, so it is possible to achieve makeup with a color close to natural light. A color rendering property of Ra 80 or higher can be realized by, for example, using a high color rendering LED, and using a white LED (around Ra 70) and a red LED in combination.

  By placing the portable oblique illumination device close to the desk, the illumination location can be easily changed simply by moving it back and forth on the desk. Alternatively, even when a mirror is provided so as to face the face during makeup, there is an advantage that the mirror does not get in the way because it is illuminated from below.

  The portable oblique illumination device according to claim 2 is characterized in that, in the invention according to claim 1, the portable oblique illumination device is capable of illuminating a human face with a predetermined illuminance distribution. .

  By dedicating the portable oblique illumination device to a person's face, it is possible to set an angle for illuminating a directional illumination to the optimal portion of the face as compared to a general-purpose illumination device. By limiting the illumination range to the periphery of the face, the periphery of the face becomes brighter, and illumination close to natural light can be realized around the face by a high color rendering light source. For example, there is no difference in color at the time of makeup, and a color environment that does not feel strange even when going outdoors is realized. Note that “a person's face can be illuminated with a predetermined illuminance distribution” means that, for example, when illuminating a person's face 15 cm away horizontally and 35-45 cm away vertically from a portable oblique illumination device, The minimum illuminance is 50% or more, and the spread of illumination light in this case is preferably 40 to 80 degrees, or 30 cm in the horizontal direction and 35 to 45 cm in the vertical direction from the portable oblique illumination device. When illuminating the face of a distant person, it is said that the minimum illuminance is 50% or more with respect to the maximum illuminance on the face. In this case, the spread of illumination light is preferably 30 to 70 degrees.

  A portable oblique illumination device according to a third aspect is the invention according to the first or second aspect, wherein the light guide plate has a rectangular shape.

  Because of this slim shape, it is easy to put vertically in a handbag pocket, etc., and it is easy to store.

  According to a fourth aspect of the present invention, in the portable oblique illumination device according to the third aspect, the light source is installed on the long side of the light guide plate, and the light emitted from the first main surface is emitted from the light source plate. The maximum luminance peak direction is inclined in a direction in which a short side extends with respect to the normal line of the first main surface.

  The light source is installed on the long side of the light guide plate, and the maximum luminance peak direction of the emitted light emitted from the first main surface extends a short side with respect to the normal line of the first main surface If the mobile phone is tilted in the direction, the entire face can be appropriately illuminated even if the portable oblique illumination device is placed near the hand without taking up space on the desk.

  According to a fifth aspect of the present invention, in the portable oblique illumination device according to any one of the first to fourth aspects, the casing has a foldable leg.

  If the portable oblique lighting device is provided with a foldable leg, the leg can be folded when being carried, and the leg can be stood up when placed on a desk. Furthermore, when used in an unstable place such as on a bag, by standing only a part of the leg part, the leg part can be stably inserted by inserting or hanging the leg part into the gap or end of the bag. An oblique illumination device can be used. In addition, as long as the same function is realizable, the shape of a leg part is not ask | required.

  A portable oblique illumination device according to a sixth aspect of the invention is characterized in that in the invention according to any one of the first to fifth aspects, a mirror connected to the housing is provided.

  By connecting a mirror to the housing, it is not necessary to carry the mirror separately. Since the portable oblique illumination device of the present invention can emit directional illumination light, even when the mirror and the housing are integrated, the reflected light to the mirror can be reduced and the glare felt by the user can be suppressed. Can do. For example, even when the mirror connected to the housing is brought close to the face during makeup, directional illumination light is emitted from the first main surface, so that the entire face is illuminated. The light that enters the eyes can be dimmed so that there is no such thing. Even when the angle between the mirror and the portable oblique illumination device is 90 ° or more, the reflection of illumination light by the mirror is small, so that glare is alleviated even when the entire face is illuminated brightly. The mirror may be removable.

  The portable oblique illumination device according to claim 7 is the invention according to any one of claims 1 to 6, wherein the color temperature of the light source can be adjusted, and the light whose color temperature is adjusted is the light source. Is emitted.

  By changing the color temperature of the light source, it is possible to change the illumination color (spectral distribution) according to the state of illumination, such as a strong reddish, yellowish, or bluish color, and vividly enhance the color. . The color temperature of the light source can be adjusted by, for example, using one or more LEDs (for example, 6000K and 3000K LED chips, white LED chip and red LED chip) to increase or decrease one emission color by changing the current ratio. This is possible.

The portable oblique illumination device according to claim 8 is the invention according to any one of claims 1 to 7, wherein the light guide plate is formed of a material of a medium having a refractive index greater than 1.4, and the optical path deflecting unit includes: It has a plurality of inclined surfaces discretely arranged along the light guide direction of the light guide plate,
After the light from the light source is incident on the light guide plate, the light is incident on the first main surface or the second main surface at an angle including a total reflection angle, and is transmitted and refracted on the inclined surface. It comes out from the surface,
The light emitted from the first main surface has a luminance peak in an angle range inclined by 40 degrees or more in a direction away from the light source with respect to the normal line of the first main surface.

  As the optical path deflecting means, a plurality of inclined surfaces arranged discretely along the light guide direction of the light guide plate are provided on the first main surface, so that the second main surface includes a total reflection angle. When light incident on an angle and further reflected and directed toward the exit surface enters the inclined surface inclined so as to face the incident surface, the incident angle becomes deep, so that Fresnel reflection can be effectively reduced. Luminance light having a luminance peak in an angle range that is refracted by the inclined surface and inclined by 40 degrees or more in the direction away from the light source from the normal direction of the first main surface can be obtained. A plurality of “luminance peaks” may exist.

  The portable oblique illumination device according to claim 9 is the invention according to claim 8, characterized in that an inclination angle γ of the inclined surface with respect to the first main surface is 25 degrees to 40 degrees.

  Thereby, high intensity light can be emitted in a direction inclined by 40 degrees or more from the normal direction of the first main surface.

  The portable oblique illumination device according to claim 10 is the invention according to any one of claims 1 to 9, wherein the light source includes a plurality of light emitting portions on the first main surface and the second main surface. It is arranged at a predetermined pitch along the incident surface extending in the intersecting direction.

  The required illuminance can be obtained by using a light source having a plurality of light emitting portions. Even when a plurality of light emitting units are used, a diffusion effect is produced by transmitting the light guide plate, and uniform illumination can be realized.

  The portable oblique illumination device according to claim 11 is the invention according to any one of claims 1 to 10, wherein the light source intersects the first main surface and the second main surface of the light guide plate. It is characterized by being arranged to face only one side surface extending in the direction.

  Thereby, although the number of the light sources can be reduced and the cost can be suppressed, a bright portable oblique illumination device can be provided.

  A portable oblique illumination device according to a twelfth aspect is the invention according to any one of the first to seventh aspects, wherein the optical path deflecting means is discretely arranged on the second main surface along the incident surface. An inclined surface that extends, and the light from the light source is incident on the light guide plate, is then transmitted and refracted by the inclined surface, and is emitted from the first main surface.

  The light incident from the incident surface is reflected by the inclined surface to obtain luminance light having a luminance peak in an angle range inclined in a direction away from the light source from the normal direction of the first main surface. it can. Thereby, although it is a thin light-guide plate, the illumination light provided with directivity can be efficiently irradiated outside.

  According to a thirteenth aspect of the present invention, in the invention according to the twelfth aspect, the optical path deflecting unit is a V groove or a trapezoidal groove that is discretely arranged on the second main surface and is parallel to the incident surface. The angle θv1 formed by the inclined surface on the incident surface side and the normal line of the first main surface satisfies 50 ° <θv1 <75 °.

  Thereby, although it is a thin light-guide plate, the illumination light provided with directivity can be efficiently irradiated outside.

  A portable oblique illumination device according to a fourteenth aspect is the invention according to any one of the first to seventh aspects, wherein the optical path deflecting means is a diffusing dot, and is emitted when light enters the diffusing dot. Assuming that the diffusion angle of incident light is σ (°), 5 ° <σ <15 ° is satisfied.

  By imparting diffusion characteristics to the thin light guide plate, the illuminance distribution of the emitted light emitted from the portable oblique illumination device can be made uniform, and the luminance unevenness of the light emitting surface can be reduced. By setting the diffusion angle σ (°) to satisfy 5 ° <σ <15 °, the directivity of the illumination light can be ensured while reducing the luminance unevenness of the light emitting surface. Specifically, the luminance unevenness of the light emitting surface can be reduced by making σ larger than 5 °, and the directivity of the illumination light can be secured by making σ smaller than 15 °.

  The portable oblique illumination device according to claim 15 is the invention according to any one of claims 1 to 14, wherein an end surface intersecting the first main surface and the second main surface is light from the light source. The incident surface has a first deflecting surface and a second deflecting surface, and light from the light source passes through the first deflecting surface and then travels toward the second main surface. Is incident on the reflecting surface at an angle including a total reflection angle, and after passing through the second deflecting surface, is deflected toward the first main surface and then exits the emitting surface. Is incident at an angle including the total reflection angle, then passes through the optical path deflecting means and exits from the first main surface.

  Each of the two light beams divided by the incident surface is totally reflected and guided to the plurality of inclined surfaces in the same direction, so that the inclined direction is bright, the loss of incident light is small, and the incident surface of the light guide plate Light that directly reaches the facing surface is reduced, and light extraction efficiency is increased. That is, since the two light beams divided by the first deflection surface and the second deflection surface constituting the incident surface are totally reflected by the reflection surface and the emission surface, and are guided to the optical path deflecting unit. The number of times the light is reciprocated and guided in the light guide plate is reduced, thereby prompting the light emitted from the light source to enter the light path deflecting means without being attenuated as much as possible, thereby increasing the light extraction efficiency. It is.

  According to a sixteenth aspect of the present invention, in the portable oblique illumination device according to the fifteenth aspect, the first deflection surface and the second deflection surface are surfaces inclined in different directions.

  Light directly incident from the light source facing the incident surface is divided by the first deflection surface and the second deflection surface inclined in different directions, so that there is little light loss and light is reciprocated between end surfaces. The number of times of light decreases and the light extraction efficiency increases.

  The portable oblique illumination device according to claim 17 is the invention according to claim 15 or 16, wherein the light transmitted through the first deflection surface or the second deflection surface is first incident on the first main surface. Alternatively, it is totally reflected by the second main surface.

  Except for the diffracted light generated at the edge of the light guide plate, the light transmitted through the first deflecting surface or the second deflecting surface is totally reflected by the first main surface or the second main surface incident first. Therefore, it is possible to obtain bright illumination with low loss.

  The portable oblique illumination device according to claim 18 is characterized in that, in the invention according to any one of claims 1 to 17, a reflection plate is provided adjacent to the second main surface of the light guide plate. .

  Since the light emitted from the second main surface is reflected by the reflector, can be incident again from the second main surface, and emitted from the first main surface, a portable oblique illumination device with high emission efficiency is provided. it can.

  The portable oblique illumination device according to claim 19 is the invention according to any one of claims 1 to 18, wherein a diffusion plate is provided adjacent to the first main surface of the light guide plate. .

  By transmitting the light emitted from the emission surface through the diffuser plate, the emitted light can be appropriately spread and illuminated over a wide range, and the illuminance unevenness can be further reduced.

  ADVANTAGE OF THE INVENTION According to this invention, although it is thin and convenient for carrying, it is excellent in energy saving, can provide the portable diagonal illuminating device which can obtain the illumination suitable for makeup | decoration with high efficiency.

It is a schematic sectional drawing which shows the outline | summary of the portable diagonal illuminating device which concerns on this embodiment. It is an expanded sectional view for explanation which takes out and shows only LED2 and a part of light guide plate 1 of a first embodiment. It is a figure which shows the angle characteristic of the illumination light intensity of the portable diagonal illuminating device of 1st embodiment. It is sectional drawing similar to FIG. 2 concerning a modification. It is a figure for demonstrating the specification aspect of the portable diagonal illuminating device U of 1st embodiment. It is a figure for demonstrating another specification aspect of the portable diagonal illuminating device. It is a figure for demonstrating another specification aspect of the portable diagonal illuminating device. It is a figure for demonstrating another specification aspect of the portable diagonal illuminating device. It is a perspective view of the portable diagonal illuminating device U concerning a modification. It is a figure for demonstrating the specification aspect of the portable diagonal illuminating device. It is a figure for demonstrating the specification aspect of the portable diagonal illuminating device U of 2nd embodiment. It is a figure which shows the angle characteristic of the illumination light intensity of the portable diagonal illuminating device of 2nd embodiment. It is a figure for demonstrating the specification aspect of the portable diagonal illuminating device U of 3rd embodiment. It is a figure which shows the angle characteristic of the illumination light intensity of the portable diagonal illuminating device of 3rd embodiment. It is a figure for demonstrating the specification aspect of the portable diagonal illuminating device U of 4th embodiment. It is a figure for demonstrating the specification aspect of the portable diagonal illuminating device U of 5th embodiment. It is an enlarged view for demonstrating the specification aspect of the portable diagonal illuminating device U of 5th embodiment. It is a perspective view of the light-guide plate provided with the diffusion dot used in 5th embodiment. It is a figure which shows the angle characteristic of the illumination light intensity | strength of the portable diagonal illuminating device of 5th embodiment. In the illumination light of the portable diagonal illuminating device of 5th embodiment, it is a figure which takes an illuminance ratio on a vertical axis | shaft and takes a position on a horizontal axis.

  Embodiments of the present invention will be described below with reference to the drawings. Moreover, the same code | symbol is used about the same structural member, and detailed description is abbreviate | omitted suitably.

  The portable oblique illumination device according to the present invention is a portable oblique illumination device U having an irradiation surface that emits surface light. For example, as shown in FIG. The light guide plate 1 provided with a second main surface 12 facing the first main surface and extending substantially in parallel, and the light guide plate 1 extending in a direction intersecting the first main surface 11 and the second main surface 12. A plurality of light-emitting elements 2 disposed to face one side surface portion (one end face) serving as an incident surface 13, and guides light emitted from the light-emitting elements 2 into the light guide plate 1. Thus, the portable oblique illumination device U for the lighting apparatus is ejected from the first main surface 11.

  The light guide plate 1 is a flat plate whose longitudinal direction is perpendicular to the paper surface, and is integrally accommodated in a case (housing) 3 together with the light emitting element 2 so as to expose the first main surface 11. Composed. A battery accommodating portion 34 is formed at the light source side end of the case 3, and the button battery BT accommodated therein is connected to the substrate 21 by a lead wire (not shown).

  The light emitting element 2 may be a light source that emits illumination light in the direction of the incident surface 13. For example, a linear light source (cold cathode tube) or a plurality of light sources arranged at intervals in the longitudinal direction of the incident surface 13 may be used. A point light source (LED) can be used. Further, it is preferable to use an LED that emits white light with low power consumption and high emission intensity. Therefore, in the present embodiment, a white LED is used. Therefore, it replaces with the light emitting element 2, and demonstrates from now on as LED2. A plurality of LEDs 2 are arranged at substantially equal intervals (for example, a pitch of about 15 mm) in the longitudinal direction (direction perpendicular to the paper surface) of the substrate 21 accommodated in the case 3.

  The LED 2 is a white LED, and emits white light by combining a blue LED and a phosphor (for example, a yellow phosphor) that is excited by light from the blue LED and emits excitation light having a predetermined wavelength. The white LED may be a high color rendering LED that is a combination of a red LED, a blue LED, and a green LED. Here, by using a high color rendering LED of Ra80 or higher, it is possible to realize a portable oblique illumination device suitable for applications requiring high color reproducibility.

  For example, the substrate 21 has a length approximately equal to the entire width in the longitudinal direction of the incident surface 13, and a plurality of chip-type LEDs 2 are mounted on the substrate 21 at a predetermined pitch. Thus, although the board | substrate 21 is united in the longitudinal direction, it is good also as a structure which divides | segments into several board | substrates and each is electrically connected. Moreover, the board | substrate 21 is connected with the button battery BT in the battery accommodating part 34 with a lead wire, and the brightness of a portable diagonal illuminating device can be adjusted by adjusting the electric current which flows into LED with a drive circuit not shown. It is. The circuit for driving the LED is well known and will not be described in detail. Further, a dial or the like for manually adjusting the brightness may be provided. Furthermore, the color temperature can be adjusted according to the user's preference by using a plurality of LEDs of different emission colors and increasing or decreasing the emission of at least one color.

  FIG. 2 is an explanatory enlarged sectional view showing only the LED 2 and a part of the light guide plate 1. The normal direction of the first main surface is the z-axis, the direction away from the light source is the x-axis, and the direction orthogonal to the z-axis and the x-axis is the y-axis (the same applies hereinafter). In FIG. 2, the incident surface 13 has a V-shaped groove shape, and has a first deflection plane 13 a and a second deflection plane 13 b that are inclined so as to approach the outer peripheral side of the LED 2 with the center in the thickness direction of the light guide plate 1 as a boundary. Therefore, the light emitted from the upper half of the LED 2 is refracted by the first deflection plane 13a and travels toward the second main surface 12, and the light emitted from the lower half of the LED 2 is refracted by the second deflection plane 13b. Then, it is directed to the first main surface 11.

  Here, the inclination angle θ of the first deflection plane 13a and the second deflection plane 13b is desirably up to 20 degrees. When the inclination is greater than 20 degrees, the high intensity light emitted from the LED 2 does not become a total reflection component on the first main surface 11 and the second main surface 12 and is emitted at a position close to the LED 2. Light extraction efficiency deteriorates. In addition, by tilting the first deflection plane 13a and the second deflection plane 13b by 20 degrees, the low-intensity light emitted from the LED 2 at a radiation angle of 70 degrees (cosine 0.34) is incident and incident on the incident plane 13 Fresnel reflection is relatively small at an angle of 50 degrees.

  On the other hand, from another viewpoint, the inclination angle θ of the first deflection plane 13a and the second deflection plane 13b is preferably equal to or greater than an angle of atan (t / (2L)). Here, referring to FIG. 2, the thickness of the light guide plate is t (mm), and the distance from the incident surface 13 to the end surface opposite to the incident surface of the light guide plate 1 is L (mm). When t = 3 and L = 55, by setting atan (t / (2L)) = 1.5 degrees or more, there is no guided light that directly reaches the end surface opposite to the incident surface 13, and high intensity light is emitted. Since it is guided to the optical path deflecting means 15 and light can be extracted in the outward path as much as possible, it is possible to prevent absorption or flare light loss due to light guide reciprocation.

  Furthermore, it is preferable that all light beams (excluding edge diffracted light) incident from the first deflection plane 13a and the second deflection plane 13b are incident on the first main surface 11 and the second main surface 12 that are incident first at a total reflection angle. . When the light guide plate 1 is formed of a material having a refractive index of 1.5, the refracted all incident light beams are refracted at the inclination angle θ of the first deflection plane 13a and the second deflection plane 13b of 6 ° or less and the first main surface 11 and the first deflection plane 13b. Two total reflections will occur at the main surface 12. However, as described above, it is desirable that the first deflection plane 13a and the second deflection plane 13b are inclined at an inclination angle θ = 1.5 degrees or more. In the present embodiment, the first deflection plane 13a and the second deflection plane 13b are each inclined by 10 degrees.

  The light emitted from the LED 2 enters from the incident surface 13 and is guided through the light guide plate 1. That is, light is guided between the lower surface (first main surface 11) and the upper surface (second main surface) of the light guide plate 1 while being totally reflected, and is directed to the optical path deflecting means 15 provided on the first main surface 11. Light that is incident and deviates from the total reflection angle is transmitted through the optical path deflecting means 15 and emitted from the first main surface 11 to emit light.

  More specifically, an optical path deflecting unit 15 is provided on the first main surface 11, and illumination light is irradiated through the optical path deflecting unit 15 by deflecting a predetermined angle from the normal direction of the first main surface 11. Yes. Referring to FIG. 2, the angle θ formed between the perpendicular line of first main surface 11 and the maximum intensity direction of the emitted light is preferably 40 degrees or more.

  The optical path deflecting means 15 shown in FIG. 2 employs a plurality of V grooves provided in the first main surface 11 and extending in the direction perpendicular to the paper surface. Further, the V groove constituting the optical path deflecting means 15 includes a first inclined surface V1A on the light source side (an inclined surface inclined so as to shift to the light source side from the reflecting surface side toward the emitting surface side) and the first inclined surface. The first inclined surface V2A and the second inclined surface V2A that forms the V-groove together with the first inclined surface V1A, and changing the inclination angle γ (30 degrees in this case) between the first inclined surface V1A and the first principal surface 11 The direction of the maximum peak intensity light of the illumination light deflected by a predetermined angle θ from the normal direction of 11 can be adjusted.

  Here, the light guide plate 1 is made of a transparent material having a refractive index of about 1.4 or more and transmitting visible light (for example, PMMA: acryl having a refractive index of about 1.5), and has a V-groove optical path deflection. The means 15 can be formed by additional machining or can be formed integrally. In addition, the light guide plate 1 may be a glass material, acrylic other than PMMA, polycarbonate, a silicon resin sheet having plasticity, or the like depending on applications.

  The V groove constituting the optical path deflecting means 15 is not provided within a predetermined distance from the incident surface 13. For example, the V-groove is not provided in the non-arrangement region Lb (see FIG. 1: about 5 mm) close to the light source, and the V-groove is provided only in the arrangement region farther from the light source. When the V-groove is provided in the vicinity of the incident surface, the LED 2 that is a point light source is discretely arranged, so that the incident light is reflected before mixing, and a bright line is generated in the vicinity of the incident surface of the portable oblique illumination device. As a result, the luminance distribution becomes uneven. Therefore, a non-arrangement region is provided so that the optical path is deflected after the incident lights overlap each other.

  By subjecting the transfer surface of the mold for forming the light guide plate 1 to a rough surface process, the first inclined surface V1A can be roughened or an anisotropic diffusion surface to have a diffusion effect as a diffusing means.

  The light beam emitted from the LED 2 is guided while being totally reflected between the first main surface 11 and the second main surface 12, and the light beam refracted by the optical path deflecting unit 15 is emitted from the first main surface 11 as illumination light. However, by disposing the reflector 4 on the outside of the second main surface 12, the light leaked to the outside of the second main surface 12 after being reflected by the optical path deflecting means 15 is reflected and guided again. The light can be returned to the inside of the optical plate 1, the intensity of the illumination light emitted from the first main surface 11 can be increased, and a highly efficient portable oblique illumination device U can be realized.

  The reflecting plate 4 may be made of a resin plate having a mirror treatment or a mirror film attached to the inner surface thereof, an aluminum sheet metal having a reflecting surface subjected to white coating white reflection treatment or mirror treatment, or the like. Moreover, you may form the inner surface of case 3 which accommodates the light-guide plate 1 as a reflective surface which gave the white reflection process and the mirror process of the white coating to the aluminum sheet metal, for example, and a reflective film (for example, Kimoto company make) (Ref white) may be used.

  A diffusion plate 5 is disposed above the light guide plate 1 via an air layer (for example, about 0.5 mm). By disposing the diffusing plate 5, illuminance unevenness and luminance unevenness on the exit surface of the portable oblique illumination device U can be reduced. In particular, it is possible to realize a high-quality portable oblique illumination device that suppresses the glare unique to the V-groove and is easy on the eyes.

  Further, if the diffuser plate 5 is arranged outside the first main surface 11, the emission surface (first main surface) even if the optical path deflecting means 15 is composed of a plurality of V grooves arranged discretely. It is possible to reduce the illuminance unevenness (brightness unevenness) of the illumination light in 11) and realize a high-quality portable oblique illumination device U that is uniform and gentle on the eyes. The diffusion plate 5 may be a conventionally known resin diffusion plate or resin diffusion film having translucency. The haze value of the diffuser plate is 65%. The haze value is a value obtained by Td / Tt × 100 (%). However, Td: diffuse transmittance, Tt: total light transmittance.

  In the present embodiment, light is guided while being totally reflected by the first main surface 11 and the second main surface 12 (light guide light having a refractive index of 1.5 and a reflection angle of 42 degrees to 83 degrees), so that the loss is kept low. Can do. In addition, the light guide light having a reflection angle of 83 to 90 degrees has a low intensity because it is light from the light source that has been refracted by the incident surface and diffracted light by the edge of the incident surface. Further, the guided light that is not totally reflected at a reflection angle of 38 to 42 degrees is low-intensity light that is emitted from the light source to the periphery, and is low-intensity because it is Fresnel-reflected on the incident surface. That is, since high intensity light is guided by total reflection, it is highly efficient.

  FIG. 3 shows the angle characteristics of the illumination light intensity of the portable oblique illumination device U of the first embodiment. The xz cross section shown in the figure corresponds to a plane parallel to the paper surface passing through the center of the portable oblique illumination device U shown in FIG. 1, that is, the upper and lower surfaces of the illumination space from the exit surface to the user's face. The yz section shown in FIG. 4 corresponds to a plane parallel to the width of the portable oblique illumination device U (direction perpendicular to the paper surface).

  The angle characteristic of the illumination light intensity shown in FIG. 3 is a calculation result by simulation. By providing the optical path deflecting means 15 formed of a V-groove having a predetermined shape on the first main surface 11 of the light guide plate 1, illumination light having an xz cross section is provided. As shown by the intensity RA, the illumination light distribution tilted from the perpendicular direction of the portable oblique illumination device U to the right side in the drawing, that is, toward the user side by a predetermined angle is shown. Further, as shown in the illumination light intensity RB of the yz section, it can be seen that the illumination light distribution changes substantially uniformly in the yz section direction.

  In this case, the high-intensity emitted light that is refracted and emitted from the inclined first inclined surface V1A has an incident angle of 23 degrees in the air, and the Fresnel reflection is small, so that the light extraction efficiency is high. Also, when an object parallel to the light emitting surface is illuminated, high intensity emitted light having an intensity peak in the direction of 53 degrees in the direction away from the light source with respect to the normal of the first main surface 11 due to the influence of the cosine component of the light emitting surface. Due to the presence, high illuminance can be obtained in a direction of about 40 degrees or more on the irradiated object side. In the illumination light intensity RA, an intensity peak near 20 degrees is reflected by the inclined first inclined surface V1A, and then reflected back by the diffuse reflection surface of the case 3 disposed on the back surface of the second main surface 12. Light emitted from the surface.

  FIG. 4 is a cross-sectional view showing the light guide plate 1 </ b> A according to the modification together with the LEDs 2. In this modification, a convex portion 15 ′ as an optical path deflecting unit is formed so as to protrude from the first main surface 11. The convex portion 15 'includes a light source side slope S1 and an opposite slope (inclined surface) S2. The slope angle γ of the slope S2 is 30 degrees. Other configurations are the same as those of the above-described embodiment. Such a convex portion 15 ′ can be transferred if a concave portion is formed in the mold, so that it can be manufactured easily and at a low cost.

  In FIG. 4, the light emitted from the lower half of the LED 2 is refracted by the first deflection plane 13a and travels toward the second main surface 12, and the light emitted from the upper half of the LED 2 is the second deflection plane 13b. After being guided through the light guide plate 1 so as to be refracted at the first principal surface 11 and then incident on the inclined surface S2, the light flux that is reflected and diffused and deviates from the total reflection angle is reflected on the first principal surface 11. Is emitted as illumination light. At this time, the light reflected by the second main surface 12 travels in the direction along the slope S1, so that it does not easily become a shadow, and the light extraction efficiency can be increased. In this modification, it is possible to emit high-intensity light having an intensity peak at an angle of θ = 53 degrees in a direction away from the light source with respect to the normal line of the first main surface 11.

  The portable oblique lighting device U of the first embodiment can be suitably applied to a portable lighting fixture. Therefore, the specification aspect of the portable oblique illumination device U of the first embodiment will be described with reference to FIG.

  In FIG. 5, the portable oblique illumination device U is placed on the desk DK at hand of the user US with the first main surface side facing up. As described above, light is emitted from the portable oblique illumination device U so that the angle θmax formed between the normal line of the first main surface and the maximum luminance peak direction of the emitted light satisfies 15 ° <θmax <60 °. Therefore, the face UF of the user US is brightly illuminated, and the user US can perform makeup while looking at the mirror MR held in the hand. The portable oblique illumination device U of the present embodiment is not dazzling even if the illumination is placed upward on the desk by directional surface emitting illumination. Therefore, even when the mirror MR is held so as to face the face UF at the time of makeup, the mirror MR is illuminated obliquely from the lower side, so that the mirror MR does not interfere with illumination, and the face UF cannot be shaded, and the face UF The whole can be illuminated. The user US can adjust the lighting condition of the face UF by appropriately moving the portable oblique illumination device U in the direction of the arrow on the desk.

  The results of studies conducted by the present inventors are shown below. Referring to FIG. 5, it is assumed that the face UF of a person US that is Lcm in the horizontal direction and Hcm in the vertical direction from the portable oblique illumination device U is illuminated with illumination light having a spread angle of A degrees. Here, conditions necessary for the minimum illuminance to be 50% or more with respect to the maximum illuminance in the face UF are summarized in Table 1.

  That is, when L = 15 cm and H = 35 to 45 cm, such as when the portable oblique illumination device U is disposed at a position close to the user US, the spread angle A at that time is set to 40 to 80 degrees. The minimum illuminance can be 50% or more with respect to the maximum illuminance at the face UF.

  On the other hand, when L = 30 cm and H = 35 to 45 cm, such as when the portable oblique illumination device U is placed away from the user US, the spread angle A at that time is set to 30 to 70 degrees. The minimum illuminance can be 50% or more with respect to the maximum illuminance in the face UF.

  FIG. 6 is a diagram showing another usage pattern of the portable oblique illumination device U, and shows a state in which a mirror MR is placed behind the portable oblique illumination device U placed on the desk DK. In this way, even when the mirror MR is placed on the back side of the portable oblique illumination device U, since the light incident on the mirror MR is small, the reflected light is suppressed from entering the eyes of the user US, and the glare is reduced. Alleviated. Moreover, since it illuminates from the slanting lower portable oblique illumination device U as in the above-described usage pattern, no shadow is formed on the face UF, and the entire face UF can be illuminated.

  FIG. 7 is a diagram showing another embodiment of the portable oblique illumination device U, and FIG. 8 is a diagram showing a usage form of the portable oblique illumination device U. As shown in FIG. 7, the portable oblique illumination device U is pivotally connected to a mirror MR by a hinge (not shown). Thus, by integrating the portable oblique illumination device U and the mirror MR, it is not necessary to carry the mirror MR separately, and it is possible to realize a compact and highly portable cosmetic tool. When carried, the portable oblique illumination device U and the mirror MR become compact, and when used, as shown in FIG. 8, the portable oblique illumination device U and the mirror MR are opened and set at about 100 degrees, The user US can perform makeup while illuminating the oblique illumination device U and looking at the mirror MR. Even if the angle between the mirror MR and the portable oblique illumination device U is 90 ° or more, because of the directional surface emitting illumination, there is little reflected light to the mirror MR, and the illumination light is not dazzled even when it enters the eyes. The mirror MR also has a function of preventing scratches on the light emitting surface as a lid of the portable oblique illumination device U. If the mirror MR can be removed, it can be used separately.

  FIG. 9 is a diagram showing another embodiment of the portable oblique illumination device U, and FIG. 10 is a diagram showing a usage form of the portable oblique illumination device U. As shown in FIG. 9A, the portable oblique illumination device U is provided with a pair of plate-like leg portions 31 that can be folded using a hinge (not shown) on the back surface of the case 3. When used on a desk, the legs 31 are set up on the desk surface. When carrying, compactness is ensured by folding the leg part 31. On the other hand, when used outside, as shown in FIG. 10, stable lighting can be performed by hooking on the depression of the bag BG placed on the knee or the like with only one leg 31 standing. In addition, as long as the same function is realizable, the shape of the leg part 31 is not ask | required.

  As shown in FIG. 9B, four rod-shaped leg portions 32 may be provided at the corners of the case 3 so as to be foldable, and as shown in FIG. By providing the projection 33 on the portion and similarly hooking it into the recess of the bag BG, stable illumination can be performed.

  Next, a second embodiment of the portable oblique illumination device will be described with reference to FIGS. The portable oblique illumination device of the second embodiment is different in that the light guide plate 1 of the portable oblique illumination device U of the first embodiment described above is replaced with the light guide plate 1B, and the other configurations are the same. Therefore, in FIG. 11, only the light guide plate 1B is displayed as the main configuration of the portable oblique illumination device.

  In FIG. 11, the inclination angle γ of the first slope V1A is 50 degrees. The other configuration is the same as the configuration shown in FIG. According to the angle characteristic of the illumination light intensity shown in FIG. 12, it is possible to emit high-intensity light having an intensity peak at an angle of θ = 55 degrees in a direction away from the light source with respect to the normal line of the first main surface 11. Light with a high emission intensity is 5 degrees in the incident angle in the air, and since the Fresnel reflection is small, it is highly efficient. The peak near 0 degree directly above the first main surface 11 is reflected by the first slope V1A, then emerges from the second main surface 12, is reflected back by the diffuse reflection surface disposed on the back surface thereof, and the first main surface 11 is reflected. It is the transmitted emitted light.

  Thus, directivity can be improved by inclining the angle of the 2nd slope V2A which connects the 1st main surface 11 and the 1st slope V1A in the direction which escapes from an outgoing direction. Further, even when a diffusion plate (haze ratio of 65%) is disposed above the first main surface 11, the diffusion plate has a low diffusion degree, so that there is little possibility of hindering directivity.

  Next, a third embodiment will be described with reference to FIGS. The portable oblique illumination device of the third embodiment is different in that the light guide plate 1 of the portable oblique illumination device U of the first embodiment described above is replaced with a light guide plate 1C, and other configurations are the same. Therefore, in FIG. 13, only the light guide plate 1C is displayed as the main configuration of the portable oblique illumination device.

  In FIG. 13, the inclination angle γ of the first slope V1A is 60 degrees. Further, the incident surface 13 is a flat surface. The other configuration is the same as the configuration shown in FIG. When the incident surface 13 is a flat surface, the direction of the high-intensity light beam of the total reflected light is nearly 10 degrees and parallel to the first main surface 11. Accordingly, the light can be extracted with high efficiency by setting the inclined surface to 60 degrees.

  According to the angle characteristics of the illumination light intensity shown in FIG. 14, it is possible to emit high-intensity light having an intensity peak at an angle of θ = 56 degrees in a direction away from the light source with respect to the normal line of the first main surface 11. Light having a high emission intensity is 4 degrees in the incident angle in the air, and is highly efficient because the Fresnel reflection is small. In the present embodiment, an intensity peak occurs at an angle of about 20 degrees on the side closer to the light source with respect to the normal line of the first main surface 11, and this is reflected by the first inclined plane V1A inclined at an inclination angle of 60 degrees. After that, the emitted light is emitted from the second main surface 12, reflected back by the diffuse reflection surface disposed on the back surface thereof, and transmitted through the first main surface 11. In other words, it can be seen that the efficiency deteriorates when the first slope V1A has an inclination angle larger than 60 degrees. When a diffusion plate (haze ratio of 65%) is arranged above the first main surface 11, there is little possibility of hindering directivity because the diffusion plate has a low diffusion degree.

  Next, a fourth embodiment will be described with reference to FIG. The portable oblique illumination device of the fourth embodiment is different in that the light guide plate 1 of the portable oblique illumination device U of the first embodiment described above is replaced with a light guide plate 1D, and the other configurations are the same. Therefore, in FIG. 15, only the light guide plate 1D is displayed as the main configuration of the portable oblique illumination device.

  In the present embodiment, the optical path deflecting means 15 in which the V grooves composed of the inclined surfaces V1A and V2A are discretely arranged is provided on the second main surface 12, and the illumination light of the light guide plate 1 is emitted when the surface light is emitted. It is possible to irradiate strong light in an inclined direction different from the perpendicular direction toward the main surface to be emitted (first main surface 11). An angle θv1 formed by the inclined surface V1A on the second main surface 12 side and the normal line of the first main surface 11 (or the second main surface 12) satisfies 50 ° <θv1 <75 °.

More specifically, an optical path deflecting unit 15 is provided on the second main surface 12, and illumination light is irradiated through the optical path deflecting unit 15 by deflecting a predetermined angle from the normal direction of the first main surface 11. Yes. Referring to FIG. 15, the angle θ _MAX formed by the perpendicular of first main surface 11 and the maximum intensity peak direction of the emitted light preferably satisfies 15 ° <θ _MAX <60 °, as will be described later.

  The optical path deflecting means 15 shown in FIG. 15 employs a plurality of V grooves provided in the second main surface 12 and extending in the direction perpendicular to the paper surface. With this configuration, since the optical path deflecting means 15 is provided on the second main surface 12 opposite to the exit surface, the illuminance distribution can be made uniform, and the illuminance distribution at the exit surface position can be made more uniform. Can be.

Further, the V groove constituting the optical path deflecting means 15 has a first inclined surface V1A (inclined surface) on the incident surface side and a second inclined surface (joint surface) V2A that forms the V groove together with the first inclined surface V1A. By changing the inclination angle between the first slope V1A and the second slope V2A, the direction of the maximum peak intensity light of the illumination light deflected by a predetermined angle θ _MAX from the normal direction of the first main surface 11 is adjusted. Can do.

  The light emitted from the LED 2 enters from the incident surface 13 and is guided through the light guide plate 1. That is, light is guided between the upper surface (first main surface 11) and the lower surface (second main surface 12) of the light guide plate 1 while being totally reflected, and enters the first inclined surface V1A of the optical path deflecting means 15. Light that is reflected and deviates from the total reflection condition is emitted from the first main surface 11 to emit light.

  Next, a fifth embodiment will be described with reference to FIGS. The optical path deflecting means provided on the light guide plate can be formed using diffusion dots in addition to the V-groove. For this purpose, a description will be given of the present embodiment in which diffusion dots DT1 are formed on the second main surface 12 as optical path deflecting means instead of V-grooves.

  This embodiment also differs only in that the light guide plate 1 of the portable oblique illumination device U of the first embodiment described above is replaced with a light guide plate 1E having diffusion dots (FIG. 16). The diffusion dot DT1 is obtained by applying diffusion ink in a dot shape. In FIG. 17, only the light guide plate 1E and the diffusion plate 5 are displayed as the main configuration of the portable oblique illumination device U according to the present embodiment.

  As shown in FIG. 18, in the light guide plate 1E, a plurality of diffusion dots DT1 are arranged on the second main surface 12 at a predetermined pitch so that the dot density gradually increases from the incident surface side. The diffusion dot DT1 has a diameter of 0.4 mm and is formed so that a predetermined diffusion characteristic, for example, a diffusion angle α satisfies 5 ° <σ <15 °. The diffusion plate 5 has a predetermined diffusion characteristic, for example, a diffusion angle β satisfying 20 ° <β <40 °.

  Here, when the diffusion angle α becomes large and approaches the perfect diffusion, the distribution of the diffused light in the diffusion dots becomes a Lambertian type, and the illumination light emitted from the portable oblique illumination device U has a substantially Lambertian type. Similarly, when the diffusion angle β of the diffusion plate becomes large and approaches perfect diffusion, the distribution of the diffused light in the diffusion dot DT1 becomes a Lambertian type, and the illumination light emitted from the portable oblique illumination device U is also a substantially Lambertian type. It has the characteristics of. That is, the illumination light intensity characteristic is substantially the same as that of the light guide plate having the V groove with the inclination angle θ1B = θ2B = 45 ° with respect to the normal line of the first main surface 11, θMAX = 0 °, and the x-axis and y-axis Has a substantially symmetrical illumination distribution.

  On the other hand, when the diffusion angles α <15 ° and β <40 °, the illumination light diffused and reflected (or refracted) by the diffusion dot DT1 and diffused by the diffusion plate has the directivity before being diffused by the diffusion dot DT1. Saved. That is, it is possible to emit illumination light that exhibits the maximum intensity in a direction inclined by a predetermined angle toward the light traveling direction. Therefore, according to the present embodiment shown in FIG. 16, the light emitted from the LED 2 and incident from the incident surface 13 of the light guide plate 1 is guided through the light guide plate 1 while being totally reflected, and is diffused into the diffusion dots DT1. By being incident, directivity is given, and when the light exits from the first main surface 11, it proceeds in an inclined direction (user side).

  FIG. 19 shows angular characteristics of illumination light intensity of a portable oblique illumination device including a light guide plate 1E on which diffusion dots DT1 (α = 10 °) are formed and a diffusion plate (β = 30 °). The illuminance ratio of the irradiated surface (here, the surface parallel to the first main surface) is shown. In this configuration, θMAX = about 20 °, and it can be seen that the positive region (user side) of the x axis is illuminated more efficiently. According to FIG. 19, as shown in the illumination light intensity RA of the xz cross section, the illumination light distribution tilted from the perpendicular direction of the portable oblique illumination device U to the right side in the drawing, that is, toward the user side by a predetermined angle. Further, as shown in the illumination light intensity RB of the yz section, it can be seen that the illumination light distribution changes substantially uniformly in the yz section direction.

  For example, a configuration in which a diffusion angle σ satisfying 5 ° <σ <15 ° can be provided by integrally forming a dot-like rough surface on the second main surface 12. It is possible to obtain a predetermined diffusion angle α by adjusting the surface roughness of the rough surface. With this configuration, since the diffusion angle σ is limited to a predetermined range, the illumination light emitted from the first main surface has a maximum intensity in a tilted direction deviating from the vertical direction of the first main surface by a predetermined angle. Illumination light having

  When diffusing dots are used as the optical path deflecting means, the light beam incident on the diffusing dots is only diffused after being diffused and emitted outside the light guide plate. The light beam that preserves the total reflection condition is further guided in the light guide plate after being deflected in the optical path. Accordingly, at least a part of the light beam reaches the end surface facing the incident surface of the light guide plate. The light that has reached the opposite end face is reflected by the end face or a casing provided outside the end face, re-enters the light guide plate, is guided to the light source inside the light guide plate, and is emitted in the direction of θ <0 °. To do. In this embodiment, in order to suppress the generation of illumination light emitted at θ <0 °, the opposite end surface of the incident surface is an absorption surface.

  The present invention is not limited to the embodiments described in the specification, and other embodiments and modifications are apparent to those skilled in the art from the embodiments and ideas described in the present specification. It is. For example, a trapezoidal groove may be provided instead of the V groove as the optical path deflecting means.

1-1E Light guide plate 2 Light emitting element (LED)
DESCRIPTION OF SYMBOLS 3 Case 4 Reflector 5 Diffuser 11 1st main surface 12 2nd main surface 13 Incident surface 14 End surface 15, 15 'Optical path deflecting means 21 Substrate 31, 32 Leg 33 Protrusion 34 Battery case V1A 1st inclined surface V2A 2nd Inclined surface DT1 Diffusion dot U Portable oblique illumination device BT Battery

Claims (19)

A light source having a plurality of light emitting points having a color rendering property of Ra80 or higher,
An incident surface on which light emitted from the light source is incident, a first main surface from which incident light is emitted, a second main surface disposed opposite to the first main surface and substantially parallel to the first main surface, and the first main surface Or a light guide plate provided with optical path deflecting means provided on the second main surface;
A housing that houses the light source and the light guide plate;
A portable oblique illumination device having a drive circuit for supplying a current from a battery to the light source,
After the light from the light source is incident from the incident surface, the light is guided between the first main surface and the second main surface, and through the optical path deflecting unit, the light from the first main surface. A portable oblique illumination device characterized in that an angle θmax formed between a normal line of the first main surface and a maximum luminance peak direction of the emitted light satisfies 15 ° <θmax <60 °. .   The portable oblique illumination device according to claim 1, wherein the portable oblique illumination device can illuminate a human face with a predetermined illuminance distribution.   The portable oblique illumination device according to claim 1, wherein the light guide plate has a rectangular shape.   The light source is installed on the long side of the light guide plate, and the maximum luminance peak direction of the emitted light emitted from the first main surface extends a short side with respect to the normal line of the first main surface. The portable oblique illumination device according to claim 3, wherein the portable oblique illumination device is inclined in a direction to be moved.   The portable oblique illumination device according to claim 1, wherein the housing has a foldable leg.   The portable oblique illumination device according to claim 1, further comprising a mirror connected to the housing.   The portable oblique illumination device according to claim 1, wherein the color temperature of the light source can be adjusted, and light having the adjusted color temperature is emitted from the light source. The light guide plate is formed from a material of a medium having a refractive index greater than 1.4, and the optical path deflecting means has a plurality of inclined surfaces arranged discretely along the light guide direction of the light guide plate,
After the light from the light source is incident on the light guide plate, the light is incident on the first main surface or the second main surface at an angle including a total reflection angle, and is transmitted and refracted on the inclined surface. It comes out from the surface,
The light emitted from the first main surface has a luminance peak in an angle range inclined by 40 degrees or more in a direction away from the light source with respect to a normal line of the first main surface. Item 8. The portable oblique illumination device according to any one of Items 1 to 7.   The portable oblique illumination device according to claim 8, wherein an inclination angle γ of the inclined surface with respect to the first main surface is 25 degrees to 40 degrees.   The light source includes a plurality of light emitting units arranged at a predetermined pitch along the incident surface extending in a direction intersecting the first main surface and the second main surface. The portable oblique illumination device according to any one of 1 to 9.   The said light source is arrange | positioned facing only one side surface extended in the direction which cross | intersects the said 1st main surface and the said 2nd main surface of the said light-guide plate, The any one of Claims 1-10 characterized by the above-mentioned. A portable oblique illumination device according to claim 1.   The optical path deflecting means is an inclined surface that is discretely arranged on the second main surface and extends along the incident surface, and the light from the light source is incident on the inclined surface after entering the light guide plate. The portable oblique illumination device according to any one of claims 1 to 7, wherein the portable oblique illumination device is transmitted and refracted and emitted from the first main surface.   The optical path deflecting means is a V-groove or trapezoidal groove that is discretely arranged on the second main surface and is parallel to the incident surface, and is formed by an inclined surface on the incident surface side and a normal line of the first main surface. 13. The portable oblique illumination device according to claim 12, wherein the angle θv1 satisfies 50 ° <θv1 <75 °.   The optical path deflecting means is a diffusing dot, and when light is incident on the diffusing dot, 5 ° <σ <15 ° is satisfied, where σ (°) is a diffusion angle of outgoing light. The portable oblique illumination device according to any one of claims 1 to 7.   An end surface intersecting the first main surface and the second main surface is an incident surface on which light from the light source is incident, and the incident surface includes a first deflection surface and a second deflection surface, Light from the light source passes through the first deflection surface, is then deflected toward the second main surface, and is incident on the reflection surface at an angle including a total reflection angle, while the second After passing through the deflecting surface, the light is deflected toward the first main surface, is incident on the exit surface at an angle including a total reflection angle, and then passes through the optical path deflecting means and passes through the first main surface. The portable oblique illumination device according to claim 1, wherein the portable oblique illumination device emits light further.   The portable oblique illumination device according to claim 15, wherein the first deflection surface and the second deflection surface are surfaces inclined in different directions.   The portable light according to claim 15 or 16, wherein the light transmitted through the first deflecting surface or the second deflecting surface is totally reflected by the first main surface or the first main surface that is incident first. Type oblique illumination device.   The portable oblique illumination device according to any one of claims 1 to 17, wherein a reflector is provided adjacent to the second main surface of the light guide plate.   The portable oblique illumination device according to claim 1, wherein a diffusion plate is provided adjacent to the first main surface of the light guide plate.

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