JP2008084560A - Lighting system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lighting system capable of providing display where light looks running, having a small number of light sources, and easy to downsize. <P>SOLUTION: A light guide body 32 is formed of a transparent resin, and a light source 31 comprising an RGB integration type LED is arranged in the vicinity of an end surface (light entering surface) thereof. A DOE (diffractive optical element) 31 having a one-dimensional spatial frequency is arranged on the undersurface side of the light guide body 32. In the DOE 31 having the one-dimensional spatial frequency, when it is assumed that an incident angle is constant, light is diffracted in a distinct direction depending on wavelength. Thereby, when the light source 31 is sequentially blinked, for instance, in the order of red, green and blue, display is implemented such that light looks running on the surface of the light guide body 32 while changing color. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an illuminating device used in an electronic device such as a mobile phone and a PDA, and more particularly to an illuminating device capable of displaying light as if traveling.

  In recent years, electronic devices such as mobile phones and PDAs (Personal Digital Assistants) have come to use lighting devices that capture light as one of the interfaces and emit light in various patterns.

  FIG. 1A is a schematic diagram illustrating an example of a conventional lighting device. In this illumination device, an LED (Light-Emitting Diode) 12a is disposed at one end of a light guide (LGP) 11 and an LED 12b is disposed at the other end. Each of these LEDs 12a and 12b is formed by integrating a red (R) light emitter, a green (G) light emitter, and a blue (B) light emitter, and the control circuit 13 controls the red light emitter, the green light emitter, and the blue light emitter. The light emission of the light emitters is individually controlled. Further, when the red light emitter, the green light emitter and the blue light emitter are caused to emit light simultaneously, white light is obtained. The light guide 11 is made of a resin mixed with a diffusing agent that diffuses light.

  In the illuminating device shown in FIG. 1A, for example, when the LED 12a arranged on the left side emits red light and the LED 12b arranged on the right side emits blue light, the surface of the light guide 11 is red from the left side to the right side. A gradation that continuously changes from blue to blue is observed.

  FIG.1 (b) is a schematic diagram which shows the other example of the conventional illuminating device. In this illuminating device, a plurality of LEDs 22 a to 22 e are arranged in one direction below the light guide 21. Each of these LEDs 22a to 22e is configured by integrating a red (R) light emitter, a green (G) light emitter, and a blue (B) light emitter, and the control circuit 23 controls the red light emitter, the green light emitter, and the blue light emitter. The light emitters are individually controlled. Also in this lighting device, the light guide 21 is formed of a resin mixed with a diffusing agent that diffuses light.

  In the illuminating device shown in FIG. 1B, for example, when the LEDs 22a to 22e emit light in red, yellow, green, light blue and blue in order from the left side, the surface of the light guide 21 is colored like a rainbow from the left side to the right side. A gradation that changes is observed. Note that yellow is obtained by simultaneously emitting red and green light emitters, and light blue is obtained by simultaneously emitting green and blue light emitters.

Patent Document 1 describes that a color filter is disposed between a light source and an optical fiber to change the color of light emitted from a light guide plate connected to the optical fiber. Patent Document 2 describes a light source unit in which light emitted from a light guide using a hologram is rainbow (rainbow color).
JP 2000-75270 A JP 2001-356703 A

  When the light is used as an information display interface, various illumination patterns are required for the illumination device. One of them is a display that allows light to run. In the illuminating device shown in FIG. 1A, it is not possible to realize a display in which light appears to run. In addition, the lighting device of FIG. 1A has a drawback that both ends are bright and the center is dark. Although it is possible to make the brightness uniform by making the distribution density of the diffusing agent in the central part of the light guide 11 higher than both sides, in that case, it becomes difficult to manufacture the light guide 11 Will occur.

  In the illuminating device of FIG.1 (b), the display which looks like light can be implement | achieved by light-emitting LED22a-22e in order. However, since the lighting device of FIG. 1B requires many LEDs, not only does the product cost increase, but the lighting device itself is increased in size, such as an electronic device that is required to be small and save power, such as a mobile phone. The problem that it becomes difficult to use it occurs.

  In view of the above, an object of the present invention is to provide an illumination device that can realize a display in which light appears to run, and can be easily miniaturized with a small number of light sources.

  According to an aspect of the present invention, the light guide includes a light guide having an incident surface on which light is incident and an output surface from which the light is emitted, and a plurality of light emitters that generate light having different wavelengths. There is provided an illumination device having a light source disposed in the vicinity of the incident surface and a diffractive optical element having a one-dimensional spatial frequency disposed on the surface of the light guide.

  The illuminating device of the present invention includes a light source including a plurality of light emitters, a light guide, and a diffractive optical element having a one-dimensional spatial frequency. In a diffractive optical element having a one-dimensional spatial frequency, if the incident angle is constant, light is diffracted in different directions depending on the wavelength. In the present invention, this characteristic is used to realize a display in which light appears to run.

  For example, when an LED in which a red light emitter, a green light emitter and a blue light emitter are integrated as a light source and these light emitters emit light simultaneously, the light is diffracted in a direction corresponding to the wavelength by a diffractive optical element. For this reason, the observer observes red, green, and blue light separately. When the red light emitter, the green light emitter, and the blue light emitter are blinked in a certain order, the light color changes and the light position also changes. That is, by controlling the light emission of the red light emitter, the green light emitter, and the blue light emitter at an appropriate timing, a display in which light appears to run while changing color is realized. In addition, the light source should just be comprised by the several light-emitting body which generate | occur | produces a mutually different wavelength.

  When the diffractive optical element is disposed on the light exit surface side of the light guide, a prism that adjusts the incident angle of light incident on the diffractive optical element to a predetermined angle is disposed on the side facing the light exit surface. Is preferred. In addition, if light incident on the light guide from the incident surface directly enters the diffractive optical element, it may become noise light and a desired display may not be obtained. For this reason, a member that prevents light entering the light guide from the incident surface from directly entering the diffractive optical element may be provided in the light guide.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

(First embodiment)
Fig.2 (a) is a schematic diagram which shows the illuminating device which concerns on the 1st Embodiment of this invention.

  The illuminating device according to the present embodiment includes a light source 31, a light guide 32, and a reflective diffractive optical element (Diffractive Optical) disposed on the back surface of the light guide 32 (the surface facing the surface from which light is emitted). Elements: hereinafter referred to as “DOE”) 33, and a control circuit (control unit) 34 that controls the light emission of the light source 31.

  The light source 31 is composed of a plurality of light emitters that generate light having different wavelengths. In the present embodiment, an RGB integrated LED in which a red (R) light emitter, a green (G) light emitter, and a blue (B) light emitter are integrated is used as the light source 31. The control circuit 34 individually controls the light emission of the red light emitter, the green light emitter, and the blue light emitter constituting the light source 31. The light source 31 is not limited to the RGB integrated LED, and may be any light source that includes a plurality of light emitters that generate light having different wavelengths. These light emitters are preferably housed in one package like RGB integrated LEDs, but may be used in combination with those individually packaged. The same applies to other embodiments.

  The light guide 32 is formed in a rod shape (cuboid shape) from a transparent resin such as PMMA (polymethyl methacrylate) or glass. The light source 31 is disposed in the vicinity of one end face (incident slope) of the light guide 32. The light generated by the light source 31 enters the light guide 32 through the end face of the light guide 32.

  The DOE 33 is disposed on the back side of the light guide 32 as described above, and has a one-dimensional spatial frequency. In the present embodiment, it is assumed that the DOE 33 is configured by rectangular unevenness arranged at a predetermined pitch on the back side of the light guide 32.

  In the DOE 33 having a one-dimensional spatial frequency, when the incident angle is constant, light is diffracted in different directions depending on the wavelength, and red light is diffracted at a larger angle than blue light. Using this characteristic, the spatial frequency of the DOE 33 and the position of the light source 31 are determined so that the wavelength (color) of the light that can be seen by the observer changes continuously according to the position of the light guide 32. . Here, the incident angle of light with respect to the DOE 33 is θi, the outgoing angle is θo, the spatial frequency of the DOE 33 (the number of line pairs (unevenness) per unit length) is f, the wavelength of light is λ, and the diffracted light order is N. Then, there is a relationship shown in the following formula (1) between them.

sin θi + sin θo = Nfλ (1)
In the illumination device of the present embodiment configured as shown in FIG. 2A, when the red light emitter, the green light emitter, and the blue light emitter of the light source 31 are turned on at the same time, the vicinity of the end near the light source 31 is An iridescent gradation of blue and red near the end on the far side is observed. In addition, by changing the light emission intensity of each of the red, green, and blue light emitters of the light source 31 at a predetermined timing, a display in which light appears to run on the surface of the light guide 32 while changing the color is realized.

  FIG. 2B schematically shows a change in the position of the light-emitting portion (light-visible portion: the same applies hereinafter) of the light guide 32 when the light source 31 emits light in the order of red, green, and blue. As described above, in the illumination device of the present embodiment, the red, green, and blue light emitters of the light source 31 are turned on and off in turn, so that the viewer can see the light on the surface of the light guide 32 from the left side to the right side. It seems to run while changing the color.

  The illumination device according to the present embodiment needs only one light source 31, and can be reduced in size and saved in power. Thereby, it can be used for a small electronic device such as a mobile phone that requires power saving. The illuminating device of this embodiment can be used for illumination when notifying an incoming call in a mobile phone, for example. Moreover, since the illumination device of the present embodiment can change the position of the light emitting part of the light guide 32 by controlling the red light emitter, the green light emitter, and the blue light emitter, for example, the remaining amount of the battery and the radio wave It can also be used as an indicator that indicates a state or the like.

  In the present embodiment, the DOE 33 is configured by irregularities arranged at a constant pitch. However, the DOE 33 may be configured by irregularities whose pitch changes continuously or intermittently.

(Second Embodiment)
FIG. 3 is a schematic diagram showing an illumination device according to the second embodiment of the present invention.

  The illumination device according to the present embodiment includes a light source 41, a light guide 42, a transmissive DOE 43 disposed on the surface of the light guide 42 (a surface from which light is emitted), and a control that controls light emission of the light source 41. And a circuit 44.

  The light source 41 is composed of a plurality of light emitters that generate light having different wavelengths. Also in the present embodiment, an RGB integrated LED in which a red light emitter, a green light emitter, and a blue light emitter are integrated is used as the light source 41. The control circuit 44 individually controls light emission of the red light emitter, the green light emitter, and the blue light emitter constituting the light source 41.

  The light guide 42 is formed in a rod shape (cuboid shape) from a transparent resin such as PMMA. The light source 41 is disposed in the vicinity of one end face of the light guide 42. The light generated by the light source 41 enters the light guide 42 through the end face of the light guide 42. In addition, on the back surface side of the light guide 42, a large number of prisms 45 that reflect light to the front surface side are provided as shown in an enlarged view in a circled portion in the drawing. These prisms 45 are formed by triangular irregularities provided on the back side of the light guide 42.

  The DOE 43 provided on the surface side of the light guide 42 has a one-dimensional spatial frequency. In the present embodiment, it is assumed that the DOE 43 is configured by rectangular unevenness provided on the surface of the light guide 42 at a constant pitch.

  As can be seen from the above equation (1), in a DOE having a one-dimensional spatial frequency, if the spatial frequency (f) is constant, the light diffraction direction (θo) is determined by the incident angle (θi) and the wavelength (λ ). In the present embodiment, the light from the light source 41 is reflected by the prism 45 and the incident angle (θi) of the light to the DOE 43 is adjusted so that the light having a predetermined wavelength is diffracted by the DOE 43 toward the eyes of the observer. is doing. Thereby, the freedom degree at the time of design of the light guide 42 or DOE43 becomes large, and design of an illuminating device becomes easy.

  4A is a plan view showing the DOE 43, and FIG. 4B is a cross-sectional view taken along the line II of FIG. 4A. In Fig.4 (a), the part which looks black shows the recessed part, and the part which looks white shows the convex part.

  As shown in FIGS. 4 (a) and 4 (b), the DOE 43 is composed of rectangular irregularities arranged at a constant pitch. The spatial frequency of the DOE 43 is expressed by the number of lines per unit length. For example, assuming that there are 250 sets of irregularities per mm, the spatial frequency is 250 line pitch (lp) / mm.

  5A to 5E are schematic views showing an example of a method for producing a molding die used for producing the DOE 43. FIG.

  First, a reticle (exposure mask) on which a preset spatial frequency pattern is drawn is prepared. Then, as shown in FIG. 5A, a photoresist is applied on the silicon substrate 51 to form a photoresist film 52. Next, stepper exposure (reduction exposure) is performed using a reticle prepared in advance, followed by development processing, and the reticle pattern is transferred to the resist film 52 as shown in FIG.

  Next, as shown in FIG. 5C, Ni (nickel) is sputtered on the entire upper surface of the silicon substrate 51 to form a base film 53. Thereafter, as shown in FIG. 5D, Ni is electroplated on the base film 73 until a sufficient thickness is formed, thereby forming a metal block 54.

  Next, as shown in FIG. 5 (e), the metal block 54 is removed from the silicon substrate 51 and processed into a predetermined shape, and then joined to the reinforcing plate 55 to form a molding die. However, when the metal block 54 has sufficient strength, the metal block 54 may be used as a molding die without joining the reinforcing plate 55.

  After the molding die with the uneven pattern formed in this way is combined with other molding dies, a transparent resin such as PMMA is injected into the space formed by those molding dies, and the conductive mold having the DOE 43 is provided. The light body 42 is formed.

  In the illumination device of the present embodiment as well, as in the first embodiment, the light appears to run while changing the color by controlling the light emission of the red light emitter, the green light emitter, and the blue light emitter of the light source 41. Display can be realized.

(Third embodiment)
FIG. 6 is a schematic view showing an illumination apparatus according to the third embodiment of the present invention.

  The illuminating device of the present embodiment includes a light source 61, a light guide 62, a transmissive DOE 63 disposed on the surface of the light guide 62 (a surface from which light is emitted), and a control for controlling light emission of the light source 61. And a circuit (not shown).

  The light guide 62 is formed in a rod shape with a transparent resin such as PMMA. In the vicinity of one end face of the light guide 62, a light source 61 composed of RGB integrated LEDs is disposed. In addition, prism surfaces 62 a, 62 b, and 62 c are provided on the back side of the light guide 62. The prism surface 62a is disposed on the side close to the light source 61, the prism surface 62c is disposed on the side far from the light source 61, and the prism surface 62b is disposed in the middle thereof. The prism surfaces 62 a and 62 c are surfaces inclined toward the center side of the light guide 62, and the prism surface 62 b is a surface parallel to the upper surface of the light guide 62. The prism surfaces 62a to 62c are provided with fine prisms (similar to the prism 45 in FIG. 3) so that the light reflected by the prism surfaces 62a to 62c is incident on the DOE 63 at a desired angle. Yes.

  In the present embodiment, the three prism surfaces 62 a to 62 c having different inclination angles are formed on the back surface side of the light guide 62, but more prism surfaces may be provided on the back surface side of the light guide 62. Further, if necessary, a metal film such as aluminum may be vapor-deposited on the prism surfaces 62a to 62c so that light is more reliably reflected by the prism surfaces 62a to 62c. Also in this embodiment, the same effects as those of the second embodiment are obtained.

  By the way, in the illuminating device thus configured, part of the light that has entered the light guide 62 from the light source 61 directly reaches the DOE 63 without being reflected by the prism surfaces 62a to 62c. Such light may cause light other than the desired wavelength (noise light) to reach the viewer's eyes and prevent desired illumination display. Therefore, the DOE 63 has high diffraction efficiency with respect to a desired incident angle condition, and with respect to light (hereinafter referred to as “unnecessary light”) that reaches the DOE 63 directly from the light source 61 (that is, without being reflected by the prism surface). Use a low diffraction efficiency.

  In the present embodiment, the spatial frequency of the DOE 63 and the position of the light source 61 are such that Nth-order diffracted light (where N is an arbitrary integer other than 0) is emitted in a direction perpendicular to the surface (exit surface) of the light guide 62. Etc. are determined. Since light that is not diffracted by the DOE 63 (0th order diffracted light) passes through the DOE 63 as it is, it is necessary to increase the angle difference between the Nth order diffracted light and the 0th order diffracted light. When the spatial frequency of the DOE 63 is low, it is preferable to determine the spatial frequency of the DOE 63 so that N is ± 1 to ± 3 (see the above-described equation (1)).

  By determining the spatial frequency of the DOE 63 in this way, unnecessary light is diffracted in a direction other than the vertical direction, for example, as shown by a broken line in FIG. 7 and does not reach the observer, and Nth order diffracted light (solid line in FIG. 7). ) Is observed by the observer, and a desired illumination display is obtained.

(Fourth embodiment)
FIG. 8 is a schematic diagram showing an illumination apparatus according to the fourth embodiment of the present invention.

  The illuminating device of this embodiment includes a light source 71 composed of RGB integrated LEDs, a light guide 72, a transmissive DOE 73 disposed on the surface of the light guide 72 (a surface from which light is emitted), and a light source 71. And a control circuit (not shown) for controlling the light emission.

  The light guide 72 is formed in a rod shape with a transparent resin such as PMMA. The light source 71 is disposed in the vicinity of one end face of the light guide 72. A plurality of prisms 74 that prevent unnecessary light from entering the DOE 73 are provided in the light guide 72. The light guide 72 is formed by the method shown in FIG.

  In other words, the second light guide is provided with a first light guide 72a having a flat upper surface and a DOE 73 formed on the upper surface side and a prism 74 having triangular irregularities on the lower surface side. The body 72b is formed separately. Thereafter, the first light guide 72 a and the second light guide 72 b are joined and integrated with an optical adhesive to form the light guide 72.

  In the illumination device of this embodiment, as shown in FIG. 10, the light output from the light source 71 is reflected by the inclined surface of the prism 74 and enters the DOE 73 at a predetermined angle. In this case, since the incident angle θin with respect to the inclined surface of the prism 74 varies depending on the position of the prism 74, the incident angle of light with respect to the DOE 73 also varies depending on the position of the DOE 73. The angle θ of the inclined surface of each prism 74 is determined so that light is incident at a desired angle according to the position of the DOE 73. Further, in the present embodiment, the prism 74 prevents light that has entered the light guide 72 from the end face of the light guide 72 from directly entering the DOE 73, so that generation of noise light due to the light is avoided. Is done.

  In addition, on the back surface side of the light guide 72, in order to prevent light reflected from the back surface from entering the DOE 73 and generating noise light, black coating that absorbs light may be applied.

(Fifth embodiment)
FIG. 11A is a top view showing an illumination device according to the fifth embodiment of the present invention, and FIG. 11B is a side view of the illumination device as seen from the direction indicated by the arrow in FIG. 11A. FIG.

  The illuminating device according to the present embodiment controls the light source 81, which is an RGB integrated LED, the light guide 82, the DOE 83 provided on the light emitting portion of the upper surface of the light guide 82, and the light source 81. And a control unit (not shown).

  In this embodiment, as shown in FIGS. 11A and 11B, a prism surface (first surface) that reflects light emitted from the light source 81 in the horizontal direction is provided on one side of the light guide 82. ) 82a, 82b, 82c. Similar to the third embodiment, the prism surfaces 82a, 82b, and 82c are provided with a prism that reflects light so that the incident angle of the light with respect to the DOE 83 becomes a predetermined angle. The light reflected by the prism surfaces 82 a, 82 b, and 82 c is further reflected in the vertical direction by a 45-degree reflecting surface (second reflecting portion) 82 d provided below the DOE 83 and is incident on the DOE 83.

  The mobile phone is required to be as thin as possible, and the thickness of the lighting device may be limited. In the illumination device of this embodiment, the light emitted from the light source 81 is reflected in the horizontal plane by the prism surfaces 81a, 82b, and 82c, and then reflected in the vertical direction by the 45-degree reflective surface 82d and is incident on the DOE 83. The lighting device can be thinned.

(DOE characteristics)
FIG. 12A is a diagram showing the relationship between the incident angle and diffraction efficiency of 0th-order diffracted light, ± 1st-order diffracted light, ± 2nd-order diffracted light,... In transmission diffraction, and FIG. It is a figure which shows the relationship between the incident angle of ± 1st order diffracted light, ± 2nd order diffracted light,. 13A shows the relationship between the incident angle and diffraction efficiency of 0th-order diffracted light, ± 1st-order diffracted light, ± 2nd-order diffracted light,... In transmission diffraction, and FIG. It is a figure which shows the relationship between the incident angle of folding light, +/- 1st-order diffracted light, +/- 2nd-order diffracted light, ..., and diffraction efficiency. However, in FIGS. 12A and 12B, the DOE spatial frequency is about 250 line pairs / mm, and in FIGS. 13A and 13B, the DOE spatial frequency is about 700 line pairs / mm. Further, the cross-sectional shapes of the DOE are all rectangular, and the phase modulation is λ / 2. In these drawings, T indicates transmitted light, and R indicates reflected light. T0 indicates 0th-order diffracted light, and R0 indicates specularly reflected light.

  As shown in FIGS. 12 (a) and 13 (a), in the case of transmission diffraction, within the range where the incident angle of light incident on the DOE from the light guide is about 30 degrees or less, ± 1st order and ± 2nd order High efficiency is stably obtained by folding light. In addition, when the light from the light source is directly incident on the DOE (which is a direct incident condition) with an incident angle of 75 degrees or more, N-order diffracted light such as ± 1st order and ± 2nd order is almost 0 including 0th order diffracted light. Yes, light is emitted outside the light guide and does not become noise light.

  On the other hand, as shown in FIGS. 12B and 13B, in the case of reflection diffraction, the diffraction efficiency of the 0th-order diffracted light (R0) is large when the incident angle is 75 degrees or more, which is the direct incident condition, Generation of N-order diffracted light such as ± 1st order and ± 2nd order is suppressed, and noise light at a new angle is not generated in the light guide. That is, since only the 0th-order diffracted light is totally reflected and propagated in the light guide plate, the illumination display is not affected.

  12 (a), 12 (b), 13 (a), and 13 (b), the spatial frequency of the DOE is 250 line pairs / mm or about 700 line pairs / mm, and the incident angle (from the light guide to the DOE). It can be understood that the influence of unnecessary light can be eliminated and desired illumination display by diffracted light can be achieved by using the incident angle with respect to the angle of 30 degrees or less.

(Example of illumination display)
FIGS. 14A and 14B show the lighting pattern of the light source when performing a display in which the light appears to run in the illumination devices of the first to fifth embodiments described above. As shown in FIG. 14 (a), the voltages applied to the red, green, and blue light emitters are instantaneously switched, whereby the light emission intensity (red (R) intensity, green (G) intensity of each light emitter. , Blue (B) intensity) changes instantaneously, and illumination changes in the order of red, yellow, green, light blue, blue, and black while light runs on the surface of the light guide.

  Further, as shown in FIG. 14B, by gradually increasing or decreasing the voltage applied to the red light emitter, the green light emitter and the blue light emitter, the light emission intensity (red (R) intensity, green color) of each light emitter. (G) Intensity, Blue (B) Intensity) gradually change, and illumination running on the surface of the light guide is displayed while the light gradually changes color.

  Hereinafter, various aspects of the present invention will be collectively described as supplementary notes.

(Appendix 1) A light guide having an incident surface on which light is incident and an output surface from which light is emitted;
Composed of a plurality of light emitters that generate light of different wavelengths, and a light source disposed in the vicinity of the incident surface of the light guide;
An illuminating device comprising: a diffractive optical element having a one-dimensional spatial frequency disposed on a surface of the light guide.

  (Additional remark 2) Furthermore, it has a control part which controls separately light emission of the several light-emitting body which comprises the said light source, The illuminating device of Additional remark 1 characterized by the above-mentioned.

  (Additional remark 3) LED which integrated red light emitting element, green light emitting element, and blue light emitting element is used as said light source, The illuminating device of Additional remark 2 characterized by the above-mentioned.

  (Additional remark 4) The said diffraction optical element is provided in the surface side facing the said output surface of the said light guide, The illuminating device of Additional remark 2 characterized by the above-mentioned.

  (Additional remark 5) The said diffraction optical element is provided in the said output surface side of the said light guide, The illuminating device of Additional remark 2 characterized by the above-mentioned.

  (Additional remark 6) The prism which controls the incident angle of the light which injects into the said diffractive optical element is arrange | positioned in the surface side facing the said output surface of the said light guide, The illumination of Additional remark 5 characterized by the above-mentioned. apparatus.

  (Supplementary note 7) The illumination device according to supplementary note 5, wherein a member for preventing light incident from the incident surface from directly entering the diffractive optical element is provided in the light guide body.

  (Supplementary note 8) The illumination device according to supplementary note 7, wherein the member is a prism, and light reflected by a surface of the prism is incident on the diffractive optical element.

  (Additional remark 9) The said light guide is orthogonal to the said in-plane direction the 1st reflection part which reflects the light which injected from the said incident surface in the in-plane direction, and the light reflected by the said 1st reflection part. The illumination apparatus according to claim 5, further comprising: a second reflection portion that reflects in a direction, and the light reflected by the second reflection portion is incident on the diffractive optical element.

  (Additional remark 10) As the said diffractive optical element, the thing whose diffraction efficiency of the light which injects from the said light guide at an incident angle of 75 degree | times or more is lower than the diffraction efficiency of the light which injects at an incident angle of 30 degrees or less is used The illumination device according to appendix 1, characterized by:

FIGS. 1A and 1B are schematic views showing a conventional lighting device. FIG. 2 (a) is a schematic diagram showing the lighting device according to the first embodiment of the present invention, and FIG. 2 (b) is a schematic diagram of the lighting device when the light source emits light in the order of red, green, and blue. It is a schematic diagram which shows the position change of the light emission part of a light body. FIG. 3 is a schematic diagram showing an illumination device according to the second embodiment of the present invention. 4A is a plan view showing a DOE (diffractive optical element), and FIG. 4B is a cross-sectional view taken along the line II of FIG. 4A. FIGS. 5A to 5E are schematic views showing an example of a method for manufacturing a molding die used for manufacturing a DOE. FIG. 6 is a schematic view showing an illumination apparatus according to the third embodiment of the present invention. FIG. 7 is a schematic diagram showing the traveling directions of Nth-order diffracted light diffracted by DOE and unnecessary light. FIG. 8 is a schematic diagram showing an illumination apparatus according to the fourth embodiment of the present invention. It is a schematic diagram which shows the formation method of the light guide of the illuminating device of 4th Embodiment. FIG. 10 is a schematic diagram showing light reaching the DOE in the fourth embodiment. FIG. 11A is a top view showing an illumination device according to the fifth embodiment of the present invention, and FIG. 11B is a side view of the illumination device as seen from the direction indicated by the arrow in FIG. 11A. FIG. FIG. 12A is a diagram showing the relationship between the incident angle and diffraction efficiency of 0th-order diffracted light, ± 1st-order diffracted light, ± 2nd-order diffracted light,... In transmission diffraction, and FIG. It is a figure which shows the relationship between the incident angle of ± 1st order diffracted light, ± 2nd order diffracted light,. FIG. 13 (a) is a diagram showing the relationship between the incident angle and diffraction efficiency of 0th-order diffracted light, ± 1st-order diffracted light, ± 2nd-order diffracted light,... In transmission diffraction, and FIG. It is a figure which shows the relationship between the incident angle of ± 1st order diffracted light, ± 2nd order diffracted light,. FIGS. 14A and 14B are timing charts showing the lighting pattern of the light source when performing a display in which light appears to run.

Explanation of symbols

11, 21, 32, 42, 62, 72, 82 ... light guide,
12a, 12b, 22a-22e ... LED,
13, 23, 34 ... control circuit,
31, 41, 44, 61, 71, 81 ... light source,
33, 43, 63, 73, 83 ... DOE (diffractive optical element),
44, 74 ... Prism,
55. Silicon substrate,
52 ... Photoresist film,
53 ... Under film,
54 ... Metal block,
55. Reinforcing plate.

Claims (5)

A light guide having an incident surface on which light is incident and an output surface from which light is emitted; and
Composed of a plurality of light emitters that generate light of different wavelengths, and a light source disposed in the vicinity of the incident surface of the light guide;
An illuminating device comprising: a diffractive optical element having a one-dimensional spatial frequency disposed on a surface of the light guide.   The lighting device according to claim 1, further comprising a control unit that individually controls light emission of a plurality of light emitters constituting the light source.   The lighting device according to claim 2, wherein an LED in which a red light emitting element, a green light emitting element, and a blue light emitting element are integrated is used as the light source.   The illumination device according to claim 2, wherein the diffractive optical element is provided on the light exit surface side of the light guide.   The illumination device according to claim 4, wherein a prism that controls an incident angle of light incident on the diffractive optical element is disposed on a surface side of the light guide opposite to the emission surface.

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