JP2019204604A - Luminaire - Google Patents

Abstract

To provide a luminaire in which emitting light presents gradation.SOLUTION: A luminaire 1 includes a transparent tabular body 10, a scattering body 20 provided at least at one main surface of the transparent tabular body 10, and a light source 30. Emission light from the light source 30 propagates in the main surface direction d of the transparent tabular body 10 inside the transparent tabular body 10. The content of scattering materials contained in the scattering body 20 is equal to or greater than 0.3% by percentage by mass, and average internal transmissivity is 1-97% at the wavelength of 380-780 nm in 50 mm length of the transparent tabular body 10.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a lighting device having a transparent plate-like body.

  In recent years, from the viewpoint of improving design and functionality, there has been a demand for a device that makes a simple window a kind of display device. 2. Description of the Related Art There is known an illumination device that displays an image or introduces light into a transparent glass so as to protect the privacy by making it invisible from the outside like a polished glass (Patent Document 1 and Patent Document 2).

  Patent Document 1 discloses a lighting device that is attached to a window glass of a predetermined size and causes a light guide plate including an LED module to emit light so that the interior is not visible from the outside. Patent Document 2 discloses a retrofitting method that can be installed relatively easily and a light emitting window unit for the subsequent method.

JP, 2006-58327, A JP 2006-81653 A

In recent years, from the viewpoint of design properties, it is sometimes preferred that the intensity distribution of light emitted from the lighting device is not uniform but exhibits gradation, that is, that the light emission intensity has a distribution.
An object of this invention is to provide the illuminating device with which the emitted light exhibits gradation.

  The illuminating device of the present invention includes a transparent plate, a scatterer provided on at least one main surface of the transparent plate, and a light source, and the light emitted from the light source is the transparent plate. The inside of the body propagates in the direction of the main surface of the transparent plate-like body, and the content of the scattering material contained in the scatterer is 0.3% or more in terms of mass percentage, and is 50 mm long of the transparent plate-like body The average internal transmittance at a wavelength of 380 to 780 nm is 1 to 97%.

  In the lighting device of the present invention, the emitted light exhibits gradation.

1 is a schematic cross-sectional view showing a first embodiment of a lighting device 1 according to the present invention. The schematic sectional drawing of the form which attached the illuminating device 1 of 1st Embodiment with respect to the existing window glass 60 from the indoor side. The schematic sectional drawing which shows 2nd Embodiment of the illuminating device 1 which concerns on this invention. The measurement result of the luminance of the test body 12. The content of Fe ₂ O ₃ contained in the transparent plate-shaped object of the test specimens of Examples, and the content of the scattering material contained in the scattering body, a graph showing the relationship between the a.

  Hereinafter, the details and other features of the present invention will be described based on embodiments for carrying out the invention. In the following drawings, the same or corresponding members or parts are denoted by the same or corresponding reference numerals, and redundant description is omitted. Also, the drawings are not intended to show relative ratios between members or parts unless otherwise specified. Thus, specific dimensions can be selected as appropriate in light of the following non-limiting embodiments.

  In the present specification, “to” indicating a numerical range is used in the sense of including the numerical values described before and after the numerical value as a lower limit value and an upper limit value.

  A preferred embodiment of a lighting device according to the present invention will be described in detail with reference to FIGS.

  FIG. 1 is a schematic cross-sectional view showing a first embodiment of a lighting device according to the present invention. Based on FIG. 1, the illuminating device of this embodiment is explained in full detail.

  The illuminating device 1 of this embodiment is provided with the transparent plate-like body 10 which is transparent plate shapes, such as a window glass and a transparent resin body, the scatterer 20 provided in the transparent plate-like body 10, and the light source 30. ing.

  The transparent plate-like body 10 has a predetermined thickness and length, and has an end surface 11 in the thickness direction and a main surface 12 in the length direction. The transparent plate 10 is a transparent glass plate, transparent resin (organic glass) or the like, and if it is a transparent resin, for example, an acrylic resin, a polycarbonate resin, a polyimide resin, a PET resin, an FRP material, or the like is used. Is more preferable. For easy understanding, one of the main surfaces 12 is a first main surface 12a, and a main surface facing the first main surface 12a is a second main surface 12b.

  The transparent plate-like body 10 has an average internal transmittance of 1 to 97% at a wavelength of 380 to 780 nm at a length of 50 mm. When the average internal transmittance at a wavelength of 380 to 780 nm at a length of 50 mm is 97% or less, the light guided through the transparent plate 10 is attenuated, and the light emitted from the lighting device exhibits gradation. The average internal transmittance at a wavelength of 380 to 780 nm at a length of 50 mm is preferably 95% or less, more preferably 90% or less, further preferably 85% or less, particularly preferably 80% or less, and most preferably 75% or less. If the average internal transmittance at a wavelength of 380 to 780 nm at a length of 50 mm is too low, the lighting device 1 does not emit light. Therefore, the average internal transmittance at a wavelength of 380 to 780 nm at a length of 50 mm is 1% or more, and 5% or more. Preferably, 10% or more is more preferable, and 20% or more is more preferable.

  The average internal transmittance at a wavelength of 380 to 780 nm at a length of 50 mm is obtained as follows. The transmittance T (λ) at a length of 50 mm is such that the dimension of the main surface is 50 mm long × 50 mm wide, and the two end faces facing each other perpendicular to the main surface have an arithmetic average roughness Ra ≦ 5 nm. In the sample of the polished transparent plate-like body, the slit is cut by a spectrophotometer (for example, UH4150: manufactured by Hitachi High-Technologies Corporation) that is 50 mm long in the normal direction from one of the end faces and capable of measurement at a length of 50 mm. After making the beam width of incident light narrower than the plate thickness, etc., measurement is performed in the wavelength range of 380 to 780 nm.

  By removing the loss due to reflection on the surface from the thus obtained light transmittance at a length of 50 mm, the internal transmittance at a length of 50 mm can be obtained by the following procedure.

At least g line (435.8 nm), F line (486.1 nm), e line (546.1 nm), d line (587.6 nm), and C line (656.3 nm) of the sample of the transparent plate. The refractive index at a wavelength is measured by a V-block method with a precision refractometer (for example, KPR-2000: manufactured by Shimadzu Corporation), and the Sellmeier's dispersion formula [the following formula (I)] is calculated based on these values. Each coefficient B ₁ , B ₂ , B ₃ , C ₁ , C ₂ , C ₃ is determined by the method of least squares. Thereby, the refractive index n (λ) of the transparent plate-like body is obtained.
n (λ) = [1+ {B ₁ λ ² / (λ ² −C ₁ )} + {B ₂ λ ² / (λ ² −C ₂ )} + {B ₃ λ ² / (λ ² −C ₃ ) }] ^0.5 (I)

Based on the refractive index n (λ) obtained by the formula (I), the reflectance R (λ of one side of the rectangular parallelepiped transparent plate-like body is obtained by the relational expression of the refractive index and the reflectance [the following formula (II)]. )
R (λ) = (n (λ) −1) ² / (n (λ) +1) ² (II)

Since the transmittance T (λ) is a measurement value influenced by the surface reflection of the transparent plate-like body, it is necessary to exclude the influence of the surface reflection in order to obtain the internal transmittance T _inner (λ). Therefore, the internal transmittance T _inner (λ) at a length of 50 mm of the transparent plate is obtained by the following formula (III).
T _inner (λ) = − [(1−R (λ)) ² + {(1−R (λ)) ⁴ + 4R (λ) ² T (λ) ² } ^0.5 ] / 2R (λ) ² T (λ (III)

  The transparent plate 10 preferably has a visible light transmittance of 85% or less at a length of 50 mm. If the visible light transmittance is 85% or less, the light guided through the transparent plate 10 is attenuated, and the light emitted from the illumination device tends to exhibit gradation. The visible light transmittance is preferably 80% or less, more preferably 75% or less, and further preferably 70% or less. If the visible light transmittance is too low, the lighting device 1 does not emit light. Therefore, the visible light transmittance is preferably 1% or more, more preferably 5% or more, further preferably 10% or more, and particularly preferably 20% or more. The visible light transmittance is obtained by a method defined in JIS R 3106 (1998).

When the transparent plate-like body 10 is a glass plate, it is preferable that the transparent plate-like body 10 contains 1 to 1000 ppm of Fe ₂ O ₃ in terms of oxide-based mass parts per million. If Fe ₂ O ₃ is 1000ppm or less, the transmittance at a wavelength of 380~780nm the transparent plate-shaped object is high, it is possible to improve the brightness of the lighting device 1. Fe ₂ O ₃ is more preferably 500 ppm or less, further preferably 300 ppm or less, still more preferably 150 ppm or less, particularly preferably 100 ppm or less, and most preferably 25 ppm or less. Further, _Fe 2 _{O 3} is equal to 1ppm or more, it is possible to lower the transmittance at a wavelength of 380 to 780 nm. Moreover, the solubility of glass can be improved. Fe ₂ O ₃ may be 2 ppm or more, 5 ppm or more, or 10 ppm or more.

When the transparent plate-like body 10 is a glass plate, the composition of the glass plate is expressed in terms of mass percentage on the basis of oxide, and SiO ₂ is 60 to 85%, Al ₂ O ₃ is 0 to 10%, and MgO is 0 to 10 %, 0-20% of CaO, the SrO 0 to 15%, 0 to 15% of BaO, 2 to 20% of Na ₂ O, _0% to _{K 2 O,} B ₂ O ₃ 0-20% It is preferable to contain.

  If it is the above-mentioned composition, intensity | strength becomes strong as the transparent plate-shaped object 10, and it is excellent also in a weather resistance, and is especially preferable as an exterior material.

When the transparent plate 10 is a glass plate, the mass ratio of the Fe ²⁺ amount to the total Fe amount is preferably 60% or less, more preferably 50% or less in order to reduce the in-plane chromaticity difference of the lighting device 1. 30% or less is more preferable, and 15% or less is particularly preferable. Further, the lower limit of the mass ratio of the Fe ²⁺ amount relative to the total Fe amount is not particularly limited, but may be 0.1% or more, or 1% or more in order to improve the solubility of the glass when producing a glass plate. It may be 2% or more, or 5% or more.

  The thickness of the transparent plate 10 is preferably 1 to 10 mm. If the thickness of the transparent plate-like body 10 is 1 mm or more, the strength is increased. The thickness of the transparent plate-like body 10 is more preferably 2 mm or more, and further preferably 2.5 mm or more. Moreover, if the thickness of the transparent plate-like body 10 is 10 mm or less, it is lightweight. The thickness of the transparent plate-like body 10 is more preferably 6 mm or less, and further preferably 4 mm or less.

  The scatterer 20 is provided on at least one main surface 12 (the second main surface 12b side in this embodiment). The scatterer 20 is formed in a solid or dot shape by a wet coating method (spin coating method, spray coating method, dip coating method, die coating method, curtain coating method, screen printing method, pad printing method, ink jet method, flow coating method, A gravure coating method, a bar coating method, a flexo coating method, a slit coating method, a roll coating method, a sponge coating method, and the like). Further, it may be provided on the entire second main surface 12b or may be partial. In the embodiment, it is provided on the second main surface 12b side, but may be provided on the first main surface 12a side.

  The scatterer 20 has an effect of extracting light from the light source 30 from the inside of the transparent plate-like body 10 to the outside, and can illuminate the lighting device 1 brightly. The scatterer 20 includes a resin and a scattering material.

  Examples of the resin contained in the scatterer 20 include an acrylic resin, an acrylic urethane resin, a polyester acrylate resin, a polyurethane acrylate resin, an epoxy acrylate resin, a polyester resin, a polyolefin resin, a urethane resin, and an epoxy resin. Polycarbonate resin, cellulose resin, acetal resin, vinyl resin, polystyrene resin, polyamide resin, polyimide resin, melamine resin, phenol resin, silicone resin, polyarylate resin, polyvinyl alcohol resin And thermoplastic resins such as polyvinyl chloride resins, polysulfone resins, and fluorine resins, thermosetting resins, and ionizing radiation curable resins. Among these, the use of a thermoplastic resin is preferable from the viewpoint of the moldability of the sheet-like transparent molded body, but is not particularly limited. As the thermoplastic resin, acrylic resins, polyester resins, polyolefin resins, vinyl resins, polycarbonate resins, and polystyrene resins are preferably used. Polymethyl methacrylate resin, polyethylene terephthalate resin, polyethylene naphthalate resin More preferably, polypropylene resin, cycloolefin polymer resin, cellulose acetate propionate resin, polyvinyl butyral resin, polycarbonate resin, and polystyrene resin are used. These resins can be used alone or in combination of two or more. Examples of the ionizing radiation curable resin include acrylic, urethane, acrylic urethane, epoxy, and silicone resins. Among these, those having an acrylate-based functional group, such as relatively low molecular weight polyester resins, polyether resins, acrylic resins, epoxy resins, urethane resins, alkyd resins, spiroacetal resins, polybutadiene resins, polythiol polyene resins, many Monofunctional monomers such as ethyl (meth) acrylate, ethylhexyl (meth) acrylate, styrene, methylstyrene, N-vinylpyrrolidone as oligomers or prepolymers such as (meth) arylate of polyfunctional compounds such as polyhydric alcohols and reactive diluents And polyfunctional monomers such as polymethylolpropane tri (meth) acrylate, hexanediol (meth) acrylate, tripropylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate Preferred are those containing a relatively large amount of rate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, etc. . Further, the ionizing radiation curable resin may be mixed with a thermoplastic resin and a solvent. Examples of thermosetting resins include phenolic resins, epoxy resins, silicone resins, melamine resins, urethane resins, urea resins, and the like. Among these, epoxy resins and silicone resins are preferable. A calcined product of hydrolyzate of alkoxysilane (sol-gel silica) or silazane may be used. Examples of alkoxysilane include tetraalkoxysilane (tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, etc.), alkoxysilane having a perfluoropolyether group (perfluoropolyether triethoxysilane, etc.), perfluoroalkyl. Group-containing alkoxysilane (perfluoroethyltriethoxysilane, etc.), vinyl group-containing alkoxysilane (vinyltrimethoxysilane, vinyltriethoxysilane, etc.), epoxy group-containing alkoxysilane (2- (3,4-epoxycyclohexyl), etc. ) Ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, etc.) Alkoxysilanes (3-acryloyloxy propyl trimethoxysilane and the like) or the like having a Riroiruokishi group.

  The scattering material is a plurality of light scattering particles, and examples thereof include air bubbles, inorganic particles, resin particles, and glass. In addition, metal fine particles such as aluminum, silver, platinum, gold, copper, titanium, nickel, tin, tin-cobalt alloy, indium and chromium, or metal fine particles made of titanium oxide, aluminum oxide and zinc sulfide, glass Examples include a glittering material in which a metal or a metal oxide is coated, or a glittering material in which a natural mica or a synthetic mica is coated with a metal or a metal oxide.

  The scatterer 20 contains 0.3% or more of the scattering material in terms of mass percentage. If the content of the scattering material is 0.3% or more, the light emitted from the lighting device forms a gradation. The content of the scattering material is preferably 0.5% or more, more preferably 0.8% or more, and further preferably 1.0% or more. Moreover, although the upper limit of content of a scattering material is not specifically limited, In order to make the whole main surface of the scatterer 20 shine, content of a scattering material is preferable 4.0% or less. The content of the scattering material is preferably 3.0% or less, more preferably 2.0% or less, further preferably 1.5% or less, and particularly preferably 1.2% or less.

  The scatterer 20 may have a binder that binds a plurality of light scattering particles. The binder has a refractive index different from that of the light scattering particles, and examples thereof include a resin and glass.

  The light source 30 is an LED, an organic EL, a phosphor, a laser, or the like, and is disposed on the end surface 11 of the transparent plate-like body 10, and the light emitted from the light source 30 enters the end surface 11 of the transparent plate-like body 10. Light emitted from the light source 30 propagates in the main plate direction d of the transparent plate 10 inside the transparent plate 10. The LED may be a tape LED in which LED chips are arranged in a line, or an LED vision in which LED chips are arranged in a plane.

  Moreover, the illuminating device 1 of this embodiment is provided with the supporting member 40 which supports the transparent plate-like body 10, the scatterer 20, and the light source 30. In the present embodiment, the support member 40 is provided so as to support the end surfaces of the transparent plate-like body 10 and the scatterer 20, but the support member 40 supports at least one end surface of the transparent plate-like body 10. As long as it is provided, it may be provided only on one end face of the transparent plate-like body 10, may be provided only on two end faces, or may be provided in a frame shape around the transparent plate-like body 10. Good. The support member 40 is not limited to the case where it is provided on the entire at least one end face of the transparent plate-like body 10, and may be provided on a part of at least one end face of the transparent plate-like body 10.

  In the illumination device 1 of the present embodiment, the content of the scattering material contained in the scatterer 20 is 0.3% or more in terms of mass percentage, and the average at a wavelength of 380 to 780 nm in a 50 mm length of the transparent plate-like body. When the internal transmittance is 1 to 97%, the lighting device 1 exhibits gradation.

  The thickness of the scatterer 20 is preferably 5 to 30 μm. If it is 5 μm or more, a sufficient scattering effect is exhibited. 7 μm or more is more preferable, and 10 μm or more is more preferable. Moreover, if it is 30 micrometers or less, the adhesiveness to the transparent plate-shaped body 10 will be good, and film | membrane hardness will become large. 25 μm or less is more preferable, and 20 μm or less is more preferable.

In the illumination device 1 of the present embodiment, the content of the scattering material contained in the scatterer 20 is expressed in terms of mass percentage x (%), and the content of Fe ₂ O ₃ contained in the transparent plate 10 is based on the oxide. It is preferable that a represented by the following formula (1) is −170 or more, where z is a value represented by y (ppm) and x × log ₁₀ y in mass parts per million.
a = −14.9z ² + 108.8z−308.1 Formula (1)

“a” is an index representing the strength of gradation of the lighting device 1. As a is larger, the light intensity distribution becomes more prominent. If a is −170 or more, the intensity distribution of light emitted from the lighting device is not uniform and exhibits gradation. On the other hand, if a is more than −110, the gradation becomes stronger and light is emitted from a part of the main surface of the transparent plate 10 and the main surface of the scatterer 20. This is because the luminance decreases as the distance from the end face 11 on which light is incident.
In order for the main surface of the transparent plate-like body 10 and the entire main surface of the scatterer 20 to shine and exhibit gradation, a is preferably −170 to −110. a may be −160 or more, may be −150 or more, and may be −140 or more. Further, a may be −120 or less, or −130 or less.
In order to exhibit a gradation by illuminating a part of the main surface of the transparent plate 10 and the main surface of the scatterer 20, a is preferably more than -110. a may be −105 or more, or may be −100 or more.

  The illuminating device 1 of this embodiment may be used as exterior materials, such as a window, and may be used as interior materials, such as a lighting fixture.

Further, for the purpose of protecting the scatterer 20, the transparent plate-like body 10 may be laminated via the scatterer 20.
Moreover, it is good also as the laminated glass which further combined the transparent plate-like body with the transparent plate-like body 10 via the scatterer 20 and the intermediate film.

The illuminating device 1 of this embodiment can also be attached to the existing window glass.
FIG. 2 is a schematic cross-sectional view of a form in which the lighting device 1 of the present embodiment is attached to the existing window glass 60 from the indoor side. The lighting device 1 is attached by the spacer 80 so that the scatterer 20 faces the existing window glass 60 supported by the support member 70. The spacer 80 is disposed along the side edge of the main surface of the scatterer 20 facing the existing window glass 60. Thereby, the distance between the existing window glass 60 and the scatterer 20 is kept constant by the spacer 80. The illuminating device 1 may be attached so that the transparent plate-like body 10 faces the existing window glass 60.
The spacer 80 may be a metal spacer mainly made of aluminum or the like, or may be a resin spacer, and the spacer body is made of a hard resin and has a surface coated with a metal sheet such as aluminum. May be.

  FIG. 3 is a schematic cross-sectional view showing a second embodiment of the illumination device according to the present invention. The lighting device 1 of the present embodiment further includes a transparent member 50 provided on the transparent plate-like body 10. In addition, in order to make explanation easy to understand, the surface on which the transparent member 50 is provided in the main surface 12 is a first main surface 12a, and the opposite surface is a second main surface 12b.

  The transparent member 50 is disposed in the vicinity of the end surface 11 on the side of at least one main surface 12 (the first main surface 12a in the present embodiment), and reflects a light incident surface 51 on which light from the light source 30 is incident, and the incident light. The light reflecting surface 52 and the light emitting surface 53 that emits light in the direction of the transparent plate-like body 10 are provided. Further, the transparent member 50 has a triangular cross section, and may be a quadrangle or the like. Further, the transparent member 50 may be a columnar member extending from the end surface 11 of the transparent plate-like body 10 toward the center and extending in a columnar shape, and may be a triangular prism or a quadrangular prism. If it is a columnar member, the light from the light source 30 can be efficiently guided to the transparent plate 10. Of course, the shape of the transparent member 50 is not limited to that of the embodiment.

  The transparent member 50 is a transparent glass plate, transparent resin (organic glass), or the like. If the transparent member 50 is a transparent resin, for example, an acrylic resin, a polycarbonate resin, a polyimide resin, a PET resin, an FRP material, or the like is particularly used. preferable.

  The transparent member 50 is fixed to the first main surface 12a of the transparent plate 10 with an adhesive or the like, but the average refractive index of the adhesive at 380 to 780 nm is that of the transparent plate 10 and the transparent member 50. What is as close as possible to the average refractive index at 380 to 780 nm is preferable. Specifically, the absolute value of the difference between the average refractive index at 380 to 780 nm of the adhesive and the average refractive index at 380 to 780 nm of the transparent plate 10 is 0.04 or less, and 380 to 380 of the adhesive. The absolute value of the difference between the average refractive index at 780 nm and the average refractive index at 380 to 780 nm of the transparent member 50 is 0.04 or less. Examples of the adhesive include urethane adhesives, polyester adhesives, epoxy adhesives, α-cyanoacrylate adhesives, acrylic adhesives, and the like containing a compound having a hydrolyzable silyl group. It is done.

  The light source 30 is separated from the transparent member 50, and is disposed on the first main surface 12 a side of the transparent plate 10 and at a position that does not interfere with the support member 40. The light source 30 has a light emitting surface 31 that emits light, and the light emitted from the light source 30 is incident on the light incident surface 51 of the transparent member 50 disposed in the vicinity of the end surface 11 of the transparent plate 10. Here, the light incident surface 51 and the light source 30 face each other. The light source 30 is arranged so that outgoing light can enter the light incident surface 51 of the transparent member 50. The light emitting surface 31 is preferably arranged to be inclined with respect to the thickness direction of the transparent plate-like body 10. The arrangement angle of the light emitting surface 31 corresponds to the angle of the light incident surface 51 of the transparent member 50 and is determined toward the direction in which the second main surface 12b of the transparent plate 10 is optically efficiently irradiated.

  Moreover, in this embodiment, although the transparent member 50 is arrange | positioned in the vicinity of the end surface 11, it is not limited to this, You may arrange | position in the center part of the transparent plate-shaped object 10. FIG. By selecting the position where the transparent member 50 is disposed, the position where the transparent plate-like body 10 emits light can be selected. The transparent member 50 is preferably disposed in the vicinity of the end surface 11 in order to make the entire transparent plate-like body 10 shine.

  Further, the transparent member 50 may be disposed in the vicinity of any end surface 11 of the transparent plate-like body 10. The position where the transparent member 50 is disposed can be appropriately selected depending on the application. When the transparent plate-like body 10 is used as a window, the transparent member 50 may be disposed in the vicinity of the lower end surface 11, may be disposed in the vicinity of the upper end surface 11, or may be disposed in the vicinity of the right end surface 11. You may arrange | position and may arrange | position in the vicinity of the left end surface 11. FIG.

  In the illumination device 1 of the present embodiment, the light source 30 is at a position where it does not interfere with the support member 40, and is arranged so that the emitted light can enter one surface of the transparent member 50. Thereby, the light source 30 can be easily arranged, and the light from the light source 30 passes through the transparent member 50 and enters the transparent plate 10, and the light is scattered by the scatterer 20, so that the transparent plate 10 can emit light. It is said.

  And it is preferable that the absolute value of the difference of the average refractive index in 380-780 nm of the transparent member 50 and the average refractive index in 380-780 nm of the transparent plate-shaped body 10 is 0.04 or less. Thereby, reflection between the transparent member 50 and the transparent plate-like body 10 can be suppressed, and light from the light source 30 can be efficiently introduced into the transparent plate-like body 10. The absolute value of the difference between the average refractive index at 380 to 780 nm of the transparent member 50 and the average refractive index at 380 to 780 nm of the transparent plate 10 is more preferably 0.03 or less, and 0.02 or less. More preferably, it is particularly preferably 0.01 or less.

  In addition, this invention is not limited to embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably. In addition, the material, shape, dimension, numerical value, form, number, arrangement location, and the like of each component in the above-described embodiment are arbitrary and are not limited as long as the present invention can be achieved.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited by these.

The inventor produced various test bodies of the lighting device 1 and evaluated the luminance. Examples 3, 4, 6, 7, 10, and 12 are examples, and examples 1, 2, 5, 8, 9, and 11 are comparative examples.
The materials and abbreviations used in each specimen are as follows.

<Transparent plate>
(G1-G4) A glass plate was used. Table 1 shows the composition of each glass plate and the average internal transmittance at a wavelength of 380 to 780 nm at a length of 50 mm. The dimensions are 500 mm long × 300 mm wide × 3 mm thick. The average internal transmittance was determined as follows. The glass plate is polished such that the dimensions are 50 mm × 50 mm × 1.8 mm, and the arithmetic average roughness Ra of the two opposite end faces of the glass plate is 1 nm, and the optical path length in the normal direction from one of the end faces The transmittance in the case of 50 mm was measured with a spectrophotometer (UH4150: manufactured by Hitachi High-Technologies Corporation), and the average internal transmittance (%) in the wavelength range of 380 to 780 nm in the case of an optical path length of 50 mm was calculated.
(G5) An acrylic plate was used. The dimensions are 500 mm long × 300 mm wide × 3 mm thick. The average internal transmittance at a wavelength of 380 to 780 nm at a length of 50 mm was 99.2%.

<Scatterer>
(R1) Iron oxide / titanium oxide coated alumina flakes (Xirallic (registered trademark), model number: NXT M260-30 SW Leonis Gold) manufactured by Merck Co., Ltd. using a kneader as a scattering material on a silicon resin. Evenly dispersed. The dimensions are length 500 mm × width 300 mm × thickness 15 μm.
(R2) A titanium oxide-coated silica flake having a particle size of 5 to 50 μm (Colorstream, model number: T10-04 Lapis Sunlight) as a scattering material was uniformly dispersed in a silicon resin using a kneader. The dimensions are length 500 mm × width 300 mm × thickness 15 μm.
The contents of the scattering material contained in the silicon resin are shown in Tables 2 and 3.

<Light source>
(L1) A tape LED (manufactured by Nichia Corporation, NESW157BT-5000K-R70, color temperature: 5000K) in which LED spheres are arranged at intervals of 5 mm was used. The output is DC 24V, 0.75A.
(L2) A tape LED (NESL157BT-3000K-R8000, color temperature: 3000K, manufactured by Nichia Corporation) in which LED spheres are arranged at intervals of 5 mm was used. The output is DC 24V, 0.75A.

  Twelve specimens of the lighting device 1 were produced using the above materials. Tables 2 and 3 show the materials used for each specimen.

  In the test bodies of Examples 1 to 11, the scatterer 20 was laminated on one main surface (one area of 500 mm × 300 mm) of the transparent plate 10 by screen printing. The light source 30 was disposed so as to be in contact with one end face (one region of 300 mm × 3 mm) of the transparent plate-like body 10, and the support member 40 that supports the end face of the transparent plate-like body 10 and the light source 30 was attached.

  In the test body of Example 12, as shown in FIG. 3, the scatterer 20 is laminated on one main surface 12b (one region of 500 mm × 300 mm) of the transparent plate 10 by screen printing, and the cross section is a right triangle. A transparent member 50 having a triangular prism shape was attached to the other main surface 12a of the transparent plate-like body 10. In FIG. 3, e is 5.0 mm and f is 14.5 mm. Optical glass was used as the transparent member 50.

In the dark room, light from the light source 30 is emitted so as to be incident at a uniform light intensity in all regions of one end face of the transparent plate-like body 10 in the specimens of Examples 1 to 11, and in the specimen of Example 12 Is emitted so as to be incident on the end surface 51 of the transparent member 50, and the luminance of light generated from one main surface (one region of 500 mm × 300 mm) of the scatterer is 1.5 m away from the scatterer. It was measured. Since the intensity of light incident on one end face (one region of 300 mm × 3 mm) of the transparent plate 10 is uniform and the scattering material contained in the scatterer is uniformly dispersed, The luminance in the horizontal direction of the main surface is substantially the same. Therefore, the luminance was measured at the center in the horizontal direction of the transparent plate. The luminance was measured with a luminance meter (CS-100A manufactured by Konica Minolta).
In Tables 2 and 3, “◯” indicates that the light emitted from the test specimen appeared to be gradation, and “X” indicates that the light emitted from the test specimen appeared uniform.

In the test specimens of Examples 3, 4, 6, 7, 10, and 12, the content of the scattering material contained in the scatterer is 0.3% or more, and the transparent plate-like body has a wavelength of 380 to 780 nm at a length of 50 mm. Since the average internal transmittance was in the range of 1 to 97%, the light emitted from the test specimen looked gradation.
In the test bodies of Examples 1 and 8, the content of the scattering material contained in the scatterer was less than 0.3%, and the light emitted from the test body did not look gradation and appeared uniform.
In the specimens of Examples 2, 5, and 9, the average internal transmittance at a wavelength of 380 to 780 nm in a 50 mm length of the transparent plate-like body is over 97%, so that the light emitted from the specimen does not look gradation and is uniform. Looked.

The a described above was obtained as follows. FIG. 4 shows the measurement results of the luminance of the test body of Example 2. The horizontal axis is the relative value g of luminance when the vertical distance from the end surface from which the light of the transparent plate is incident is 50 mm, and the vertical axis is the end surface where the light of the transparent plate is incident. The distance h in the direction perpendicular to the end face from.
When a logarithmic approximate curve was obtained from the obtained results, it was “h = −195 × logeg + 23”, and its slope “−195” was set to a. Similarly, a was obtained for all the specimens.

Next, the relationship between a and the transparent plate-like body and scatterer was examined. As a result, the present inventors have found that there is a correlation between a, the content of Fe ₂ O ₃ contained in the transparent plate, and the content of the scattering material contained in the scatterer.
FIG. 5 shows the content of Fe ₂ O ₃ contained in the transparent plate-like body of the test bodies of Examples 2 to 4, 6, 7, 9, and 10, which are examples, and the content of the scattering material contained in the scatterer. It is the graph which showed the relationship with a. The abscissa represents the content of the scattering material contained in the scatterer 20 in terms of mass percentage x (%), and the content of Fe ₂ O ₃ contained in the transparent plate 10 represents the oxide based mass percentage. X × log ₁₀ y (= z) where y (ppm) is given, and the vertical axis is a. By obtaining a polynomial approximate curve, the following equation (1) was derived when z = x × log ₁₀ y.
a = −14.9z ² + 108.8z−308.1 (1)
In the specimens of Examples 3, 4, 6, 7, 10, and 12, a was −170 or more, the intensity distribution of light emitted from the specimen was remarkable, and the gradation was strong.
In the test bodies of Examples 3, 6, 7, 10, and 12, a is in the range of −170 to −110, and light is emitted from the main surface of the transparent plate 10 and the entire main surface of the scatterer 20. It was.
In the test body of Example 4, a was more than −110, and light was emitted from a part of the main surface of the transparent plate 10 and the main surface of the scatterer 20.

DESCRIPTION OF SYMBOLS 1 Illuminating device 10 Transparent plate-like body 20 Scattering body 30 Light source 40 Support member 50 Transparent member

Claims (11)

A transparent plate,
A scatterer provided on at least one main surface of the transparent plate;
A light source,
The emitted light from the light source propagates inside the transparent plate-like body in the main surface direction of the transparent plate-like body,
The content of the scattering material contained in the scatterer is 0.3% or more in terms of mass percentage,
The illuminating device whose average internal transmittance in wavelength 380-780 nm in 50 mm length of the said transparent plate-shaped object is 1 to 97%.   The lighting device according to claim 1, wherein the content of the scattering material included in the scatterer is 4.0% or less in terms of mass percentage.   The lighting device according to claim 1, wherein the scattering material is a glittering material obtained by coating natural mica or synthetic mica with a metal or a metal oxide.   The lighting device according to any one of claims 1 to 3, wherein the transparent plate-like body has a thickness of 1 to 10 mm.   The lighting device according to any one of claims 1 to 4, wherein a transparent member is provided on at least one main surface of the transparent plate-like body.   The lighting device according to claim 1, wherein the transparent plate is a glass plate. The lighting device according to claim 6, wherein the content of Fe ₂ O ₃ contained in the glass plate is 1 to 1000 ppm in terms of parts per million by mass based on oxide. The content of the scattering material contained in the scatterer is expressed in mass percentage x (%), and the content of Fe ₂ O ₃ contained in the glass plate is expressed in oxide based mass percentage y (ppm). The lighting device according to claim 6, wherein a represented by the following formula (1) is −170 or more, where z is a value represented by x × log ₁₀ y.
a = −14.9z ² + 108.8z−308.1 (1)   The lighting device according to claim 8, wherein the a is −110 or less.   The lighting device according to claim 8, wherein a is greater than −110. The glass plate is expressed in terms of mass percentage based on oxide, SiO ₂ is 60 to 85%, Al ₂ O ₃ is 0 to 10%, MgO is 0 to 10%, CaO is 0 to 20%, and SrO is 0 to 15%. % 0 to 15% of BaO, 2 to 20% of Na ₂ O, _0% to _{K 2 O,} wherein the B 2 _{O 3} in any one of claims 6-10 containing 0-20% Lighting equipment.

Images