JP2020145036A - Lamp for movable body - Google Patents

Abstract

To acquire high contrast in a lamp for a movable body that controls a light flux by arranging a liquid crystal element on a light path.SOLUTION: A lamp 100 for a movable body divides incident light into two pieces of polarization and uses both pieces of polarization. The lamp 100 for a movable body is disposed with at least one absorption type wire grid polarizer with an absorption layer as a first polarizer 16 or second polarizer 20.SELECTED DRAWING: Figure 1

Description

The present invention relates to a moving light.

In recent years, a variable light distribution light (ADB: Adaptive Driving Beam) capable of controlling a light distribution pattern according to the situation of an oncoming vehicle, a vehicle in front, or the like has been adopted as a headlight of an automobile. In particular, a light distribution variable lamp using a liquid crystal element capable of quickly transmitting or blocking a light flux is known.

For example, the light emitted from the light source is separated into two polarized partial optical paths, a first liquid crystal mask, a first polarizing filter and a first lens are arranged on the first partial optical path, and a first lens is placed on the second partial optical path. Disclosed is an automobile headlight in which two liquid crystal masks, a second polarizing filter, and a second lens are arranged, and the first lens and the second lens have different focal lengths (Patent Document 1).

Japanese Unexamined Patent Publication No. 2017-212210

By the way, in the moving body illuminating lamp whose light flux is controlled by arranging a liquid crystal element on the optical path, there is a problem that a high contrast between the irradiated portion and the non-irradiated portion cannot be obtained due to the influence of stray light inside the device. ..

An object of the present invention is to improve the glare of an oncoming vehicle, the visibility of the own vehicle, and the like by improving the contrast of the headlight for a moving body.

One aspect of the present invention is a mobile headlight that separates incident light into two polarized lights and utilizes both of the polarized lights, in which at least one absorbing wire grid polarizer having an absorbing layer is arranged. It is a moving light that is characterized by being polarized light.

Here, a beam splitter that separates the incident light into the polarized light, a liquid crystal element arranged on the optical path of the polarized light, a first wire grid polarizer arranged on the incident surface side of the liquid crystal element, and the liquid crystal. A second wire grid polarizing element arranged on the exit surface side of the element is provided, and at least one of the first wire grid polarizer and the second wire grid polarizer is the absorption type wire grid polarizer. Suitable.

Further, in the absorption type wire grid polarizer, it is preferable that the absorption layer is arranged on a surface facing the liquid crystal element.

Further, the beam splitter includes a third wire grid polarizer, the third wire grid polarizer is the absorption type wire grid polarizer, and the absorption layer is arranged on the light emitting surface side. Is preferable.

Further, it is preferable that the absorption type wire grid polarizer includes a wire grid made of metal, and the absorption layer is formed on the upper surface or the lower surface of the wire grid according to the shape of the wire grid.

Further, the absorption layer is preferably a dye-based polarizing layer obtained by stretching a polyvinyl alcohol film dyed with a dichroic dye.

Further, it is preferable that the absorption layer is formed on the upper surface of the wire grid, and the extending direction of the wire grid and the transmission axis of polarized light are parallel to each other.

Further, it is preferable that the liquid crystal element is driven by a driving element made of a low-temperature polysilicon layer.

Further, it is preferable that the 1/2 wavelength plate is arranged on one of the polarized light paths.

Further, it is preferable that the 1/2 wavelength plate is arranged on the incident surface side of the first wire grid polarizer.

Further, the liquid crystal element is preferably composed of a first liquid crystal element arranged on one optical path of the polarized light and a second liquid crystal element arranged on the other optical path of the polarized light.

Further, the absorption type wire grid polarizer may be composed of a grid-like structure that is transparent to the incident light and fine particles that are embedded in the gaps between the structures and are opaque to the incident light. Suitable.

Further, it is preferable that the absorption type wire grid polarizer contains a non-conductive material in which the product kd of the extinction coefficient k and the layer thickness d is 200 μm or more when the extinction coefficient k and the layer thickness d are taken.

Further, the liquid crystal element is preferably a reflective liquid crystal element.

Further, it is preferable to provide a lens capable of optimal irradiation on the optical path of the light transmitted through the wire grid polarizer at night to confirm a traffic obstacle at a distance of 40 m in front of the wire grid polarizer.

According to the present invention, it is possible to obtain high contrast in a moving headlight that controls a luminous flux by arranging a liquid crystal element on an optical path.

It is a figure which shows the structure of the illumination lamp for a moving body in embodiment of this invention. It is a figure which shows the structure of the polarizer in the embodiment of this invention. It is a figure which shows the structure of the polarizer in the embodiment of this invention. It is a figure which shows the structure of the polarizer in the embodiment of this invention. It is a figure which shows the structure of the illumination lamp for a moving body in the modification 1. It is a figure which shows the structure of the illumination lamp for a moving body in the modification 2. It is a figure which shows the structure of the illumination lamp for a moving body in the modification 3. It is a figure which shows the structure of the illumination lamp for a moving body in the modification 4. It is a figure which shows the structure of the illumination lamp for a moving body in the modification 5.

As shown in FIG. 1, the moving light 100 according to the embodiment of the present invention includes a light source 10, a beam splitter 12, a reflector 14, a first polarizing element 16 (16a, 16b), a liquid crystal element 18, and a second. It includes a splitter 20 (20a, 20b) and a lens 22 (22a, 22b).

The moving body lighting 100 is mounted on a moving body such as an automobile, and is used as a headlight or the like that illuminates the moving direction of the moving body. In particular, it functions as a variable light distribution light (ADB) capable of controlling a light distribution pattern according to the situation of an oncoming vehicle, a vehicle in front, or the like by a camera attached to the vehicle or other sensing. As a result, the irradiation portion such as a road or a passerby can obtain a good field of view while blocking the irradiation to the oncoming vehicle or the like to prevent glare.

The light source 10 is a member that outputs light emitted from the moving body illumination lamp 100. The light source 10 can be, for example, a light emitting diode (LED), a laser diode (LD), a halogen lamp, a high-pressure mercury lamp (HID), or the like. When an LED or LD is applied as the light source 10, it is preferable that a large number of individual LED elements are arranged in a two-dimensional matrix. The light source 10 outputs a substantially parallel, non-diffusing luminous flux composed of unpolarized light.

The beam splitter 12 is an optical element that separates the luminous flux from the light source 10 into two. That is, a part of the light incident on the beam splitter 12 is reflected, and the remaining part is transmitted. In the present embodiment, the beam splitter 12 is a polarizing beam splitter capable of separating the light incident from the light source 10 into polarization components orthogonal to each other. The beam splitter 12 can be configured to include a wire grid polarizer.

In the example of FIG. 1, the beam splitter 12 is arranged so as to be inclined by 45 ° with respect to the optical path of the light emitted from the light source 10. The beam splitter 12 separates the light incident from the light source 10 into polarization components (indicated by dots in the figure) perpendicular to the paper surface, reflects the light at 45 °, emits the light to the first optical path S1, and emits the light from the light source 10. The incident light is separated into polarization components (indicated by line marks in the figure) parallel to the paper surface and transmitted through the second optical path S2 along the incident direction of the light. However, the beam splitter 12 is not limited to such a configuration, and may be a beam splitter 12 that separates the polarization components of the light incident from the light source 10 in different directions.

The reflector 14 is a mirror that reflects light to change the direction of the optical path. The reflecting mirror 14 is arranged so as to reflect the light incident along the second optical path S2 at 45 °. As a result, the first optical path S1 and the second optical path S2 become substantially parallel optical paths. The reflector 14 may have a structure in which silver (Ag) is vapor-deposited on a substrate such as glass.

The first polarizer 16 is an optical element that transmits only the light of the polarizing component in a specific direction to the incident light and blocks the light of the polarizing component in the other direction. In the moving body illumination lamp 100 of FIG. 1, the first polarizing element 16a is arranged on the first optical path S1, and the first polarizing element 16b is arranged on the second optical path S2. The first polarizer 16a is arranged so that the transmission axes coincide with the polarized light separated along the first optical path S1 by the beam splitter 12. That is, the transmission axis of the first polarizer 16a is arranged so as to transmit the light of the polarization component in the direction perpendicular to the paper surface and block the polarization component in the other direction. The first polarizer 16b is arranged so that the transmission axes coincide with the polarized light separated along the second optical path S2 by the beam splitter 12. That is, the transmission axis of the first polarizer 16b is arranged so as to transmit the light of the polarization component in the direction parallel to the paper surface and block the polarization component in the other direction.

As described above, by providing the first polarizers 16 (16a, 16b) on the incident surface side of the liquid crystal element 18, as compared with the configuration in which the polarizer is not provided on the incident surface side of the liquid crystal element as in the prior art. The contrast of the light emitted from the moving body illumination lamp 100 can be improved.

The liquid crystal element 18 is an optical element including a liquid crystal layer capable of switching between a state of transmitting incident light and a state of blocking incident light. The liquid crystal element 18 is not particularly limited, but may be a drive type such as a TN system, a VA system, or an IPS system. Further, it is preferable that the liquid crystal element 18 constitutes a liquid crystal driving element with a low-temperature polysilicon layer. The liquid crystal element 18 has a configuration in which a large number of liquid crystal cells (pixels) are arranged in a two-dimensional matrix, and each liquid crystal cell (pixel) can be transitioned between a state in which incident light is transmitted and a state in which incident light is blocked. Is preferable. The liquid crystal element 18 is arranged so as to straddle the first optical path S1 and the second optical path S2. Therefore, the liquid crystal element 18 can control the light transmittance of the first optical path S1 and the light transmittance of the second optical path S2 to emit light having a free shape and intensity.

The second polarizer 20 is an optical element that transmits only the light of the polarizing component in a specific direction to the incident light and blocks the light of the polarizing component in the other direction. In the moving body illumination light 100 of FIG. 1, the second polarizing element 20a is arranged on the first optical path S1, and the second polarizing element 20b is arranged on the second optical path S2. The second polarizer 20a is arranged so that the transmission axes coincide with the polarization along the first optical path S1 transmitted by the liquid crystal element 18. That is, the second polarizer 20a transmits light on the first optical path S1 converted from the polarization component in the direction perpendicular to the paper surface to the polarization component in the direction parallel to the paper surface by the liquid crystal element 18, and polarizes in the other direction. The transmission axis is arranged so as to block the components. The second polarizer 20b is arranged so that the transmission axis coincides with the polarization along the second optical path S2 transmitted by the liquid crystal element 18. That is, the second polarizer 20b transmits light on the second optical path S2 converted from the polarization component in the direction parallel to the paper surface to the polarization component in the direction perpendicular to the paper surface by the liquid crystal element 18, and polarizes in the other direction. The transmission axis is arranged so as to block the components.

The lens 22 is an optical element that converges the transmitted light at the focal length. In the moving body illumination light 100 of FIG. 1, the lens 22a is arranged on the first optical path S1 and the lens 22b is arranged on the second optical path S2. For example, the focal length f1 of the lens 22a of the first optical path S1 and the focal length f2 of the lens 22b of the second optical path S2 may be different. As a result, the light incident on the lens 22a along the first optical path S1 is irradiated so as to converge at the focal length f1, and the light incident on the lens 22b along the second optical path S2 is converged at the focal length f2. Can be irradiated. That is, it is possible to focus on different positions depending on the moving body illumination lamp 100.

In the moving body lighting 100, the light irradiation position, the irradiation range, and the irradiation intensity can be appropriately changed by controlling the light source 10 and the liquid crystal element 18. For example, when the moving body lighting 100 is mounted as a headlight of an automobile, a variable light distribution light capable of controlling a light distribution pattern according to the situation of an oncoming vehicle, a vehicle in front, a pedestrian, or the like. It can be used as (ADB).

Here, it is preferable that the first polarizer 16 is an absorption type wire grid polarizer having an absorption layer. Further, it is preferable that the second polarizer 20 is also an absorbent wire grid polarizer having an absorbing layer.

As shown in FIG. 2, the wire grid polarizer (WGP) has a configuration including an array of grids 32 arranged parallel to the surface of a transparent substrate 30 such as glass or resin. That is, it comprises a single periodic array of wire-like grids 32 on the substrate 30. When the period of the wire-shaped grid 32 is larger than about half of the wavelength of light, the wire grid polarizer behaves as a diffraction grating. When the period of the wire-shaped grid 32 is smaller than approximately half the wavelength of light, the wire grid polarizer behaves as a polarizer.

The substrate 30 is a member that structurally supports the structure 34 and the grid 32. The substrate 30 is made of a material having translucency with respect to a wavelength region of light to be polarized. When the light to be polarized is visible light, the substrate 30 can be, for example, a glass substrate. Further, the substrate 30 may be, for example, polymethylmethacrylate (PMMA), polycarbonate (PC), cycloolefin (COP), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), triacetate cellulose (TAC) or the like. It is preferable that the substrate 30 has no or small phase difference in the plane direction.

The structure 34 is a member for repeatedly providing an uneven structure on the surface of the substrate 30. That is, the structure 34 has a structure in which a linear structure extending along the Y direction is periodically and repeatedly arranged along the X direction. The structure 34 is made of a material having translucency with respect to the wavelength of light to be polarized. Specifically, the structure 34 preferably has a transmittance of 85% or more with respect to the wavelength of light to be polarized. When the light to be polarized is visible light, it is preferable that the structure 34 is a resin such as an epoxy resin, a polyimide resin, an acrylic resin, or a polycarbonate resin having translucency in the wavelength region of visible light. is there. The structure 34 is preferably, for example, a UV curable resin selected from the NIAC series manufactured by Daicel. Further, the structure 34 may have a multi-layer structure in which a plurality of different types of resins are laminated. By forming the structure 34 into a multi-layer structure, it is possible to form a structure 34 having the characteristics of each resin layer.

The grid 32 is a member for polarizing light by reflecting or absorbing light. The grid 32 has a linear structure that is repeatedly arranged on the surface of the substrate 30. That is, the grid 32 has a configuration in which linear structures extending along the Y direction are periodically and repeatedly arranged along the X direction.

The grid 32 is provided so as to be embedded in the recess of the structure 34 having the repeatedly uneven structure. However, the structure 34 may not be provided and only the grid 32 may be provided.

In the present embodiment, as shown in the cross-sectional view of FIG. 3, the grid 32 has a configuration in which the reflection polarizer 32a and the absorption layer 32b are superposed. The reflection polarizer 32a is made of a material that is opaque to the wavelength of light to be polarized. When the light to be polarized is visible light, the reflected polarizer 32a is, for example, a metal such as silver, copper, gold, aluminum, zinc, tungsten, nickel or platinum, or a metal such as tin oxide, indium oxide or zinc oxide. It can be composed of oxides and the like. It is preferable that the reflection polarizer 32a has a height of, for example, several tens to several hundreds of μm. The reflective polarizer 32a transmits light that oscillates in a direction orthogonal to the longitudinal direction of the grid 32, and reflects light that oscillates in a direction parallel to the longitudinal direction of the grid 32.

The absorption layer 32b has a property of absorbing at least a part of incident light. The absorption layer 32b can be, for example, silicon, germanium, or amorphous silicon. In FIG. 3, the absorption layer 32b is provided on the reflection polarizer 32a, but the reflection polarizer 32a and the absorption layer 32b may be interchanged. Further, the absorption layers 32b may be provided on both sides of the reflection polarizer 32a. Further, in FIG. 3, the absorption layer 32b is provided on the upper surface side of the substrate 30, but the absorption layer 32b may be provided on the lower surface side of the substrate 30. The absorption layer 32b may be provided on the side opposite to the reflective polarizer 32a with the substrate 30 interposed therebetween.

In the grid 32, for example, an aluminum layer having a thickness of 200 μm is formed as a reflective polarizer 32a on a substrate 30 such as TAC, and an amorphous silicon layer having a thickness of 20 nm is formed on the substrate 30 as an absorption layer 32b. It can be formed by processing them into a grid shape using the above. The grid 32 can also be formed by applying nanoimprint lithography technology (NIL). Specifically, a negative-shaped resist pattern is formed on the substrate 30 by nanoimprint, an unnecessary resist is removed by ashing, and then an aluminum layer is formed as a reflective polarizer 32a by CVD, and an amorphous silicon layer is absorbed. A continuous film is formed as 32b. Then, the grid 32 can be created by removing the resist by applying a method called lift-off. In addition, the reflective polarizer 32a can also be formed using metal self-assembly techniques (see Macromolecular Chemistry and Physics, Vol.217, No. 6 (2016)).

Further, for example, the grid 32 may be formed by applying a dispersion liquid in which fine particles of the material constituting the grid 32 are dispersed in the gaps of the structure 34 having the repeatedly uneven structure. As a method for applying the dispersion liquid, for example, a spin coating method can be applied. Further, a method of filling the gaps of the structure 34 with the dispersion liquid by utilizing the capillary phenomenon may be applied.

Here, it is preferable that the fine particles contain 20% or more of the particle size equal to or less than the gap (approximately the width W1 of the grid 32) of the structure 34. By setting the particle size to such a value, the fine particles can be appropriately filled in the recesses of the structure 34 having the repeatedly uneven structure. Further, the dispersion medium for dispersing the fine particles may be, for example, water, an organic solvent (alcohol, etc.) or the like. The concentration of the fine particles in the dispersion is preferably 10% or more and 90% or less. The grid 32 can be formed by removing the dispersion medium contained in the dispersion liquid coated in this way. For example, the dispersion medium can be removed by evaporating the dispersion medium by heating in a state where the dispersion liquid is applied. If necessary, the application of the dispersion liquid and the removal of the dispersion medium may be repeated.

At this time, a plurality of different materials may be laminated to form the grid 32. For example, fine particles made of a material such as silver (Ag) for forming the reflective polarizer 32a may be applied, and fine particles made of a material such as carbon black for forming the absorption layer 32b may be applied. In this case, a dispersion liquid in which fine particles made of a material such as silver (Ag) are dispersed is applied and dried to form a reflective polarizer 32a. Then, a dispersion liquid in which fine particles made of a material such as carbon black are dispersed is applied and dried to form an absorption layer 32b.

The periodic structure of the grid 32 is set according to the wavelength of light to be polarized. The pitch P on which the grid 32 is arranged is preferably set to 1/5 to 1/2 times the wavelength of the light to be polarized. For example, when the light to be polarized is visible light, the pitch P of the grid 32 is preferably 400 nm or less, and more preferably 150 nm or less. Further, the width W1 of the grid 32 is preferably 200 nm or less, and more preferably 30 nm or more and 100 nm or less. Therefore, the pitch P of the structure 34 is also 400 nm or less, and the width W2 of the structure 34 is a value obtained by subtracting the width W1 of the grid 32 from the pitch P, and is preferably 50 nm or more and 120 nm or less, for example.

Further, the layer thickness d of the grid 32 is preferably 200 nm or more. Further, the aspect ratio (layer thickness d / width W1) of the grid 32 is preferably 2 or more. Further, when the grid 32 has an extinction coefficient k and a layer thickness d, the product kd of the extinction coefficient k and the layer thickness d is preferably 100 nm or more, and more preferably 200 nm or more. is there. Here, the extinction coefficient k is the change in intensity due to the absorption of light in the substance I = I ₀ exp (-ax) (however, the initial intensity I _{0 of the} light incident on the substance, the absorption coefficient a, and the thickness of the substance. It is a coefficient expressed by the relationship of the absorption coefficient a = 4πk / λ (however, the wavelength λ of light) when expressed by (x). Further, when the grid 32 has a multilayer structure, when the extinction coefficient of the material of the nth layer is k (n) and the layer thickness d (n), the extinction coefficient k (n) and the layer thickness d of each layer are taken. It is preferable that the sum of the products of (n), Σk (n) and d (n), is 200 nm or more. For example, in the grid 32 having a two-layer structure, when the first grid layer has an extinction coefficient k1 and a layer thickness d1, and the second grid layer has an extinction coefficient k2 and a layer thickness d2, k1 · d1 + k2 · d2 It is preferably 200 nm or more. By satisfying the condition of the product kd of the extinction coefficient k and the layer thickness d, excellent polarization characteristics can be obtained in both transmission and reflection even when the pitch P of the grid 32 is 400 nm or less.

In addition, such a wire grid polarizer can be obtained from the market under the product name Proflux PPL05C or Proflux PFU01C (both manufactured by Polatechno Co., Ltd.).

Further, a flattening layer may be provided on the surfaces of the grid 32 and the structure 34. The flattening layer is preferably a resin layer having a thickness of about 1 μm. Further, the refractive index of the flattening layer is preferably 1.5 or less, and more preferably 1.4 or less.

Further, the absorption layer 32b may include a polarizing element obtained by stretching a PVA-based resin (for example, a polyvinyl alcohol film) dyed with a dichroic dye. The thickness of the absorption layer 32b is preferably, for example, about 5 μm. The absorption layer 32b has an absorption axis in the stretching direction, and the absorption axis is arranged so as to be parallel to the extension direction of the grid 32.

The dichroic dye is preferably composed of a dye-based material. As the dichroic dye, for example, an azo compound, an anthraquinone compound, a tetrazine compound, a salt thereof, or the like can be used. Among them, when an azo compound or a salt thereof or the like is used, not only the optical characteristics are excellent, but also the durability of the optical characteristics under high temperature conditions and high temperature and high humidity conditions is higher than when iodine is used. Since it is excellent, long-term reliability can be obtained when used in a harsh environment such as a vehicle. Further, it is possible to obtain a polarizer in which the optical waveform and the hue are optimally adjusted for the moving body illumination lamp 100 by blending various dyes.

The following dyes can be exemplified as the azo compound dye.

(1) An azo compound represented by the chemical formula (1) or a salt thereof disclosed in the republished patent WO2009 / 057676 (A1).
(In the formula, R ₁ represents a hydrogen atom, a lower alkyl group, a lower alkoxyl group, a hydroxyl group, a sulfonic acid group, or a carboxyl group, and R _{2 to} R ₅ independently represent a hydrogen atom, a lower alkyl group, and a lower alkoxyl. Indicates a group or an acetylamino group, where X is a benzoylamino group which may have a substituent, a phenylamino group which may have a substituent, a phenylazo group which may have a substituent, or a substituent. It is a naphthotriazole group which may have, m is 1 or 2, n is 0 or 1.

(2) An azo compound represented by the chemical formula (2) disclosed in the republished patent WO2007 / 145210 (A1) or a salt thereof.
(In the formula, A represents a phenyl group having a substituent or a naphthyl group having 1 to 3 sulfonic acid groups, X represents -N = N- or -NHCO-, and R _{1 to} R ₄ are respectively. It independently indicates a hydrogen atom, a lower alkyl group or a lower alkoxyl group, and indicates m = 1 to 3, n = 0 or 1).

(3) Trisazo dye represented by the chemical formula (3) disclosed in the republished patent WO2006 / 057214 (A1).
(In the formula, R ₁ represents a sulfonic acid group, a carboxyl group or a lower alkoxy group, and R ₂ represents a sulfonic acid group, a carboxyl group, a lower alkyl group or a lower alkoxy group, where both R ₁ and R ₂ represent. Except for sulfonic acid groups. R _{3 to} R ₆ are independent hydrogen atoms, lower alkyl groups or lower alkoxyl groups, and R ₇ and R ₈ are independent hydrogen atoms, amino groups, hydroxyl groups, sulfonic acid groups or carboxyls. Represents a group.)

(4) A metal-containing disazo compound represented by the chemical formula (4) disclosed in JP-A-2004-251963 or a salt thereof.
(In the formula, M represents a transition metal selected from copper, nickel, zinc and iron; A ¹ represents optionally substituted phenyl or optionally substituted naphthyl; B ¹ may be substituted. It represents a good 1- or 2-naphthol residue, the hydroxyl group of which naphthol is adjacent to the azo group and is complex-bonded to the transition metal represented by M; R ¹ and R ² are independent of each other. Represents hydrogen, lower alkyl, lower alkoxy, carboxyl, sulfo, sulfamoyl, N-alkyl sulfamoyl, amino, acylamino, nitro or halogen.

(5) A trisazo compound represented by the chemical formula (5).
(In the formula, A ² and B ² each independently represent optionally substituted phenyl or optionally substituted naphthyl; R ³ and R ⁴ independently represent hydrogen, lower alkyl, lower alkoxy, respectively. Represents carboxyl, sulfo, sulfamoyl, N-alkylsulfamoyl, amino, acylamino, nitro or halogen; m represents 0 or 1).

(6) A water-soluble compound represented by the chemical formula (6) disclosed in JP-A No. 3-12606 or a copper complex salt compound thereof.
(In the formula, A represents a phenyl group or a naphthyl group substituted with a methyl group, and R represents an amino group, a methylamino group, an ethylamino group or a phenylamino group.)

(7) A water-soluble disuazo compound represented by the chemical formula (7) disclosed in JP-A-59-14255, or a copper complex salt compound thereof.

(8) Others, for example, C.I. I. Direct Yellow 12, C.I. I. Direct Yellow 28, C.I. I. Direct Yellow 44, C.I. I. Direct Yellow 142, C.I. I. Direct Orange 26, C.I. I. Direct Orange 39, C.I. I. Direct Orange 71, C.I. I. Direct Orange 107, C.I. I. Direct Red 2, C.I. I. Direct Red 31, C.I. I. Direct Red 79, C.I. I. Direct Red 81, C.I. I. Direct Red 117, C.I. I. Direct Red 247, C.I. I. Direct Green 80, C.I. I. Direct Green 59, C.I. I. Direct Blue 71, C.I. I. Direct Blue 78, C.I. I. Direct Blue 168, C.I. I. Direct Blue 202, C.I. I. Direct Violet 9, C.I. I. Direct Violet 51, C.I. I. Direct Brown 106, C.I. I. Direct Brown 223 and the like. In addition, it is preferable to blend two or three or more of these dyes so as to supplement the polarization characteristics at each wavelength in the visible region and dye them on PVA to obtain a hue exhibiting neutral gray. Further, an achromatic polarizing plate series manufactured by Polatechno Co., Ltd., which is a dye-based polarizing plate designed so that the transmittance of each wavelength in the visible light region is equalized, may be used.

Examples of commercially available dyes include Kayafect Violet P Liquid (manufactured by Nippon Kayaku Co., Ltd.), Kayafect Yellow Y, Kayafect Orange G, Kayafect Blue KW, and Kayafect Blue Liquid 400.

It is preferable that at least one of the first polarizer 16a and the first polarizing element 16b and the second polarizer 20a and the second polarizing element 20b is an absorption type wire grid polarizer. As a result, the stray light generated in the moving body lighting 100 can be absorbed by the absorbing layer 32b included in the absorbing wire grid polarizing element, and the contrast can be improved in the illumination by the moving body lighting 100. ..

At this time, it is preferable to arrange the absorption type wire grid polarizer so that the absorption layer 32b faces the liquid crystal element 18. That is, when the absorption type wire grid polarizer is applied to the first polarizer 16a, the first polarizer 16a is arranged so that the absorption layer 32b faces the incident surface side of the liquid crystal element 18. Similarly, when the absorption type wire grid polarizer is applied to the first polarizer 16b, the first polarizer 16b is arranged so that the absorption layer 32b faces the incident surface side of the liquid crystal element 18. When an absorption type wire grid polarizer is applied to the second polarizer 20a, the second polarizer 20a is arranged so that the absorption layer 32b faces the exit surface side of the liquid crystal element 18. Similarly, when the absorption type wire grid polarizer is applied to the second polarizer 20b, the second polarizer 20b is arranged so that the absorption layer 32b faces the exit surface side of the liquid crystal element 18.

Further, even if absorption layers are provided on both the incident surface and the exit surface of the first polarizing elements 16a and 16b and the second polarizing elements 20a and 20b, the contrast in the moving body illumination lamp 100 can be improved.

In the moving light 100, stray light is generated when light is incident on the liquid crystal element 18 or when light is emitted from the liquid crystal element 18, and the contrast of the light emitted by the stray light may be lowered. Therefore, by arranging the absorption type wire grid polarizer so that the absorption layer 32b faces the liquid crystal element 18, the stray light generated by the liquid crystal element 18 can be effectively absorbed, and the moving body illumination lamp 100 can be used. It is possible to improve the contrast of the irradiation light of.

The contrast of the moving headlight 100 is measured by using the Ushio, Inc. spectral radiance meter USR-45 series, and when the light from the light source 10 is transmitted and blocked by the control of the liquid crystal element 18, the moving body is used. It was obtained by measuring the brightness emitted from the illuminating lamp 100.

Further, the beam splitter 12 may be used as an absorption type wire grid polarizer. As a result, the beam splitter 12 can also improve the contrast of the irradiation light from the moving body illuminating light 100 by absorbing the stray light in the moving body illuminating light 100.

For example, it is preferable to arrange the beam splitter 12 so that the absorption layer 32b is located on the light emitting surface side. As a result, the stray light generated in the reflector 14 and the first polarizing element 16 and returned to the first polarizing element 16 can be effectively absorbed by the absorption layer 32b. Thereby, the contrast of the irradiation light from the moving body illumination lamp 100 can be improved.

When the drivers of automobiles wear polarized sunglasses, the absorption axis of the sunglasses and the polarization axis of the light emitted from the moving light 100 may coincide with each other and may not be visible. In the moving body illumination lamp 100 shown in FIG. 1, since the light emitted from the lens 22a and the light emitted from the lens 22b have polarization components orthogonal to each other, at least one of the polarization axes of the light is the absorption axis of the sunglasses. Since they do not match, visibility to the driver wearing polarized sunglasses can be ensured.

[Modification 1]
FIG. 5 shows the configuration of the moving body illumination lamp 102 in the first modification of the above embodiment. In the moving light 102, the 1/2 wavelength plate 24 is arranged on one of the polarized light paths separated into the first optical path S1 and the second optical path S2 by the beam splitter 12.

In the example of FIG. 5, the 1/2 wavelength plate 24 is arranged on the second optical path S2 between the reflector 14 and the first polarizer 16. Thereby, the polarization directions (directions perpendicular to the paper surface) of the light incident on the first polarizer 16 in the first optical path S1 and the second optical path S2 can be aligned. However, the 1/2 wavelength plate 24 may be arranged in the first optical path S1 between the beam splitter 12 and the first polarizer 16. In this case, the polarization directions (directions parallel to the paper surface) of the light incident on the first polarizer 16 in the first optical path S1 and the second optical path S2 can be aligned.

With such a configuration, the polarization component of the first optical path S1 or the second optical path S2 is rotated by 90 degrees before being incident on the first polarizing element 16, and the first optical path is rotated 90 degrees before being incident on the first optical path 16. The polarization components of the light in S1 and the second optical path S2 can be matched. Therefore, the first polarizing element 16 and the second polarizing element 20 can be combined into one, and the configuration of the moving light 102 can be simplified.

Further, it is not necessary to control the liquid crystal element 18 in consideration of two orthogonal polarizations as in the moving headlight 100. Therefore, the configuration of the control circuit and the like of the liquid crystal element 18 can be simplified.

When the polarization directions of the light of the first optical path S1 and the second optical path S2 are the same as in the moving light 102, when the driver of the automobile wears the polarized sunglasses, the absorption axis of the sunglasses is used. If the polarization axes of the light emitted from the moving light 102 are aligned with each other, it may be difficult to visually recognize the light. Therefore, for example, the problem of visibility is solved by providing a retardation plate in either the first optical path S1 or the second optical path S2 and shifting the optical axis of the light emitted from the moving body illumination lamp 102. Can be done.

Also in the moving body illumination light 102, it is preferable that at least one of the first polarizing element 16 and the second polarizing element 20 is an absorption type wire grid polarizer. As a result, the stray light generated in the moving body illuminating light 102 can be absorbed by the absorbing layer 32b included in the absorbing wire grid polarizer, and the contrast can be improved in the illumination by the moving body illuminating light 102. ..

Further, in the moving body illumination lamp 102, the beam splitter 12 may be used as an absorption type wire grid polarizer. As a result, the beam splitter 12 can also improve the contrast of the irradiation light from the moving body illuminating light 102 by absorbing the stray light in the moving body illuminating light 102.

[Modification 2]
FIG. 6 shows the configuration of the moving body illumination lamp 104 in the second modification of the above embodiment. In the moving body lighting 104, similarly to the moving body lighting 102, the 1/2 wavelength plate 24 is placed on one of the polarized light paths separated into the first optical path S1 and the second optical path S2 by the beam splitter 12. Is placed.

The moving body illumination light 104 has a configuration in which the 1/2 wavelength plate 24 is arranged on the second optical path S2 between the beam splitter 12 and the reflector 14. Thereby, the polarization directions (directions perpendicular to the paper surface) of the light incident on the first polarizer 16 in the first optical path S1 and the second optical path S2 can be aligned.

With such a configuration, similarly to the first modification, the polarization component of the second optical path S2 is rotated by 90 degrees before being incident on the first polarizer 16, and the first is before being incident on the first polarizer 16. The polarization components of the light in the first optical path S1 and the second optical path S2 can be matched. Therefore, the first polarizing element 16 and the second polarizing element 20 can be combined into one, and the configuration of the moving body illumination lamp 104 can be simplified. Further, it is not necessary to control the liquid crystal element 18 in consideration of two orthogonal polarizations as in the moving headlight 100. Therefore, the configuration of the control circuit and the like of the liquid crystal element 18 can be simplified.

Also in the moving body illumination lamp 104, it is preferable that at least one of the first polarizing element 16 and the second polarizing element 20 is an absorption type wire grid polarizer. As a result, the stray light generated in the moving body illuminator 104 can be absorbed by the absorption layer 32b included in the absorbing wire grid polarizer, and the contrast can be improved in the illumination by the moving body illuminating light 104. ..

Further, in the moving body illumination lamp 104, the beam splitter 12 may be used as an absorption type wire grid polarizer. As a result, the beam splitter 12 can also improve the contrast of the irradiation light from the moving body lighting 104 by absorbing the stray light in the moving body lighting 104.

[Modification 3]
FIG. 7 shows the configuration of the moving body illumination lamp 106 in the third modification of the above embodiment. In the moving body illumination light 106, two liquid crystal elements 18a and a liquid crystal element 18b are provided as the liquid crystal element 18. That is, the liquid crystal element 18a is arranged on the first optical path S1, and the liquid crystal element 18b is arranged on the second optical path S2.

Here, it is preferable that the liquid crystal element 18a and the liquid crystal element 18b are exclusively set to either the O mode or the E mode, respectively. The O-mode liquid crystal element 18 is a mode in which the absorption axis direction of the first polarizing element 16 arranged on the incident surface side of the liquid crystal element 18 and the orientation direction of the liquid crystal element 18 are parallel. The E-mode liquid crystal element 18 is a mode in which the absorption axis direction of the first polarizer 16 arranged on the incident surface side of the liquid crystal element 18 and the orientation direction of the liquid crystal element 18 are orthogonal to each other.

With such a configuration, the configuration of the moving light 106 can be simplified and the manufacturing cost can be reduced.

Also in the moving light 106, it is preferable that at least one of the first polarizing element 16a and the first polarizing element 16b and the second polarizing element 20a and the second polarizing element 20b is an absorption type wire grid polarizer. .. As a result, the stray light generated in the moving body illuminator 106 can be absorbed by the absorption layer 32b included in the absorbing wire grid polarizer, and the contrast can be improved in the illumination by the moving body illuminating light 106. ..

Further, in the moving body illumination lamp 106, the beam splitter 12 may be used as an absorption type wire grid polarizer. As a result, the beam splitter 12 can also improve the contrast of the irradiation light from the moving body lighting 106 by absorbing the stray light in the moving body lighting 106.

[Modification example 4]
FIG. 8 shows the configuration of the moving body illumination lamp 108 in the modified example 4 of the above embodiment. In the moving light 108, a beam splitter 12a arranged on the first optical path S1 and a beam splitter 12b arranged on the second optical path S2 are provided as the beam splitter 12. The beam splitter 12a splits the light incident from the light source 10 into two, a first optical path S1 and a second optical path S2. In the moving light 108, for example, the beam splitter 12a separates the light incident from the light source 10 into a polarizing component perpendicular to the paper surface and reflects it on the first optical path S1 toward the liquid crystal element 18c, and is parallel to the paper surface. The polarization component is separated and transmitted through the second optical path S2 toward the beam splitter 12b. The beam splitter 12b reflects the light incident from the beam splitter 12a on the second optical path S2 toward the liquid crystal element 18d.

In the moving light 108, the liquid crystal element 18 (18c, 18d) is a reflective liquid crystal element capable of changing the state of incident polarized light by controlling the orientation state of the liquid crystal. The liquid crystal element 18c is arranged on the first optical path S1, and the liquid crystal element 18d is arranged on the second optical path S2. The liquid crystal elements 18 (18c, 18d) maintain the direction of incident polarized light by arranging a large number of liquid crystal cells (pixels) in a two-dimensional matrix and controlling the orientation state of each liquid crystal cell (pixel), or 90. It can be emitted as polarized light rotated in degrees. Therefore, the liquid crystal element 18 (18c, 18d) can control the polarization state of the light of the first optical path S1 and the polarization state of the light of the second optical path S2 to emit polarized light having a free shape and direction.

By controlling the orientation of the liquid crystal elements 18 (18c, 18d), the polarized light emitted by the liquid crystal element 18c and parallel to the paper surface passes through the beam splitter 12a and is incident on the second polarizer 20a. The second polarizer 20a is arranged so that the transmission axes coincide with each other in the same direction as the polarization along the first optical path S1. That is, the transmission axis of the second polarizer 20a is arranged so as to transmit the light of the polarizing component in the direction parallel to the paper surface and block the polarization component in the other direction. The second polarizer 20b is arranged so that the transmission axes coincide with each other in the same direction as the polarized light along the second optical path S2. That is, the transmission axis of the second polarizer 20b is arranged so as to transmit the light of the polarizing component in the direction perpendicular to the paper surface and block the polarization component in the other direction. The lenses 22 (22a, 22b) are arranged in the same manner as the moving body illumination lamp 100.

In this way, the moving body illumination lamp 108 using the reflective liquid crystal element 18 can be configured. By making the liquid crystal element 18 a reflective type, it is possible to suppress heat generation inside the moving body illumination lamp 108, and it is possible to improve the efficiency of the entire device.

In the moving light 108, the liquid crystal element 18 itself is a reflective type, but the liquid crystal element 18 may be a transmissive type and a reflecting mirror or the like is provided on the back surface thereof to function as a reflective optical element as a whole. Good.

Also in the moving body illumination lamp 108, it is preferable that at least one of the second polarizing element 20a and the second polarizing element 20b is an absorption type wire grid polarizer. As a result, the stray light generated in the moving body lighting 108 can be absorbed by the absorbing layer 32b included in the absorbing wire grid polarizer, and the contrast can be improved in the illumination by the moving body lighting 108. ..

Further, in the moving body illumination lamp 108, at least one of the beam splitter 12a and the beam splitter 12b may be used as an absorption type wire grid polarizer. As a result, the beam splitter 12a and the beam splitter 12b can also improve the contrast of the irradiation light from the moving body illuminating lamp 108 by absorbing the stray light in the moving body illuminating lamp 108.

[Modification 5]
FIG. 9 shows the configuration of the moving light 110 according to the modified example 5 of the above embodiment. The moving body illumination 110 includes a reflector 14 and a lens 22b in this order in the second optical path S2 that passes through the beam splitter 12.

In the moving body illuminating light 110, similarly to the moving body illuminating light 108, the liquid crystal element 18c is a reflective liquid crystal element capable of changing the state of incident polarized light by controlling the orientation of the liquid crystal layer. As a result, the light in the optical path S1 can be an irradiation light having a high contrast, and a highly safe ADB system becomes possible.

Also in the moving body illumination light 110, it is preferable that the beam splitter 12 is an absorption type wire grid polarizer. As a result, the stray light generated in the moving body illumination light 110 can be absorbed by the absorption layer, and the contrast in the optical path S1 can be improved.

Further, by not providing the polarizing element and the liquid crystal element in the optical path S2, the light transmitted through the beam splitter 12 can be used without loss. Further, it is preferable that the lens 22b provided on the exit side of the optical path S2 is suitable for recognizing an obstacle at a distance of 40 m ahead at night. As a result, it is possible to reduce the glare of the oncoming vehicle and improve the visibility with respect to the light irradiation by the moving body lighting 110.

10 Source, 12 (12a, 12b) Beam Splitter, 14 Reflector, 16 (16a, 16b) First Polarizer, 18 (18a, 18b, 18c, 18d) Liquid Crystal Element, 20 (20a, 20b) Second Polarizer , 22 (22a, 22b) lens, 24 1/2 wave plate, 30 substrate, 32 grid, 32a reflective splitter, 32b absorption layer, 34 structure, 100, 102, 104, 106, 108, 110 moving object illumination. light.

Claims (15)

A mobile headlight that separates incident light into two polarized lights and uses both of the polarized lights.
An illumination lamp for a moving body, characterized in that at least one absorbent wire grid polarizer having an absorbent layer is arranged. The moving light according to claim 1.
A beam splitter that separates the incident light into the polarized light,
A liquid crystal element arranged on the polarized light path and
A first wire grid polarizing element arranged on the incident surface side of the liquid crystal element, and a second wire grid polarizing element arranged on the exit surface side of the liquid crystal element.
With
An illumination lamp for a moving body, wherein at least one of the first wire grid polarizing element and the second wire grid polarizing element is the absorption type wire grid polarizing element. The moving light according to claim 2.
The absorption type wire grid polarizer is an illumination lamp for a moving body, characterized in that the absorption layer is arranged on a surface facing the liquid crystal element. The moving light according to claim 2 or 3.
The beam splitter includes a third wire grid polarizer.
The third wire grid polarizer is an absorption type wire grid polarizing element, and is a moving body illumination lamp characterized in that the absorption layer is arranged on a light emitting surface side. The moving light according to any one of claims 1 to 4.
The absorption type wire grid polarizer includes a wire grid made of metal.
An illumination lamp for a moving body, wherein the absorption layer is formed on the upper surface or the lower surface of the wire grid in accordance with the shape of the wire grid. The moving light according to claim 5.
The light absorbing layer is a dye-based polarizing layer obtained by stretching a polyvinyl alcohol film dyed with a dichroic dye. The moving light according to claim 6.
The absorption layer is formed on the upper surface of the wire grid, and is characterized in that the extending direction of the wire grid and the transmission axis of polarized light are parallel to each other. The moving light according to claim 2.
The liquid crystal element is a moving light that is characterized in that the liquid crystal is driven by a driving element made of a low-temperature polysilicon layer. The moving light according to claim 2.
A mobile headlight characterized in that a 1/2 wavelength plate is arranged on one of the polarized light paths. The moving light according to claim 9.
An illumination lamp for a moving body, characterized in that the 1/2 wavelength plate is arranged on the incident surface side of the first wire grid polarizer. The moving light according to claim 2.
The liquid crystal element is a moving body illumination characterized by comprising a first liquid crystal element arranged on one optical path of the polarized light and a second liquid crystal element arranged on the other optical path of the polarized light. light. The moving light according to any one of claims 1 to 11.
The absorption type wire grid polarizer is characterized by comprising a grid-like structure that is transparent to the incident light and fine particles that are embedded in the gaps between the structures and are opaque to the incident light. Illumination for moving objects. The moving light according to any one of claims 1 to 12.
The absorption type wire grid polarizer is for a moving body, which comprises a non-conductive material in which the product kd of the extinction coefficient k and the layer thickness d is 200 μm or more when the extinction coefficient k and the layer thickness d are taken. Illuminated light. The moving light according to claim 2.
The liquid crystal element is a moving light that is characterized by being a reflective liquid crystal element. The moving light according to claim 1.
For moving objects, the optical path of light transmitted through the wire grid polarizer is provided with a lens capable of optimal irradiation for confirming a traffic obstacle at a distance of 40 m in front of the wire grid polarizer at night. Illuminated light.