JP2020060762A - Polarized light source and display device capable of suppressing reflection of light - Google Patents

Abstract

To provide a light source and display device configured to emit light not susceptible to reflection to a surrounding environment, which may allow for not only preventing malfunction of an automatic safety device due to false recognition but also improving visibility for people.SOLUTION: Provided is a light source, or display device, capable of providing visible polarized light in such a way that vertically polarized light is incident on a reflective medium, when converting light emitted from an induced light source into polarized light, or emitting polarized light using light emitted from an induced light source, and irradiating the light reflective medium with the light.SELECTED DRAWING: Figure 1

Description

  The present invention converts a light emitted from a light inducing source into polarized light, or emits polarized light by using light emitted from a light inducing source, and irradiates light to a medium that reflects the light, when a reflective medium is used. The present invention relates to a light source or a display device capable of providing polarized light in the visible region so that polarized light in a direction perpendicular to the light source is incident.

  Generally, human eyes, a camera as an image recognition device, and the like sense light as an image of the surroundings. 2. Description of the Related Art In recent years, image recognition devices have become indispensable in automatic driving safety technology in the fields of automobiles, robots, etc. Usually, a change in light due to operation is detected using a camera to operate the automatic safety device. This automatic safety device detects not only visible light but also various light such as ultraviolet light and infrared light. Therefore, it is indispensable to eliminate malfunction in light sensing, and various related techniques are disclosed in Patent Documents 1 and 2, for example. One of the main causes of malfunction is due to reflected light. For example, if there is a puddle, snow surface, or ice surface on the road, they will function as a reflection surface of light, and if light indicating the presence of people or traffic lights is reflected on these surfaces, The safety device may erroneously recognize that there are people and traffic lights in the place. This erroneous recognition not only causes a malfunction of a car, a motorcycle, or a robot that performs autonomous driving, but may also cause erroneous recognition by human eyes.

  Such erroneous recognition can occur not only in the outdoor environment, but also in the indoor environment, in particular, due to light reflection due to water, marble, pottery, stainless furniture, and the like. In recent years, the use of devices that use the face recognition function and the motion recognition function is increasing even indoors, and thus there has been a demand for a technique that does not cause a malfunction due to a misrecognition.

Japanese Patent No. 5859897 JP, 2014-072592, A

  Conventional automatic driving safety devices and cameras have taken measures to prevent malfunctions, such as image processing on the light receiving side. However, it is difficult to determine whether the received light is the light due to reflection. Until now, the method that can prevent malfunctions has been to suppress reflection by using a camera or application on the light-receiving side. Fundamentally, measures are taken to prevent reflection of the light itself on the light-emitting side. Was not. On the other hand, the invention of the present application provides a prescription that prevents erroneous recognition caused by the light that has hitherto been emitted to the surrounding environment, not only eliminates the malfunction of the automatic safety device, but also makes it visible to humans. The present invention provides a light source and a display device that can improve the brightness.

  As a result of intensive studies to achieve such an object, the present inventors converted the light emitted from the light-induced source into polarized light, or emitted the polarized light using the light emitted from the light-induced source, PROBLEM TO BE SOLVED: To provide a light source or a display device that emits polarized light in a visible light region so that vertically polarized light is incident on a reflective medium when irradiating the medium that reflects light. Then, they have found that it is possible to prevent erroneous recognition by the human eye, erroneous recognition in a safety device that recognizes light or motion, etc., and have completed the present invention. Further, it has been found that a display device in which the light source is transparent and further can display characters and images can be realized by using the technique of the present invention. In particular, the present invention is important in that it can prevent malfunctions due to misrecognition of various devices in an environment where light reflection may occur due to a medium that reflects light.

That is, the present invention relates to 1) to 8).
1)
When the light emitted from the light-induced source is converted into polarized light or the light emitted from the light-induced source is used to emit polarized light and the medium that reflects the light is irradiated with the light, it is perpendicular to the reflective medium. A light source or display device capable of providing polarized light in the visible range such that directional polarized light is incident.
2)
The light source or display device according to 1), wherein the light transmittance is 40% or more and 100% or less.
3)
The light source according to 1) or 2), which includes a polarized light emitting element that emits polarized light in the visible range, or a display device 4).
3. The light source according to 3), wherein the polarized light emitting element is a polarized light emitting element that emits light in the visible range by utilizing light in the ultraviolet range to the near-ultraviolet visible range emitted from a light inducing source. Or display device.
5)
An optical system comprising the light source or display device according to any one of 1) to 4) above and a medium capable of reflecting light.
6)
The light source according to any one of 1) to 4) or the display device or the optical system according to 5), which is used outdoors.
7)
The light source according to any one of 1) to 4), or the display device, or the optical system according to 5), which is used for a driving device.
8)
The light source according to any one of 1) to 4), the display device, or the optical system according to 5), which is used for vehicles such as automobiles, motorcycles, bicycles, and ships.

  When the light emitted from the light-induced source is converted into polarized light or the light emitted from the light-induced source is used to emit polarized light and the medium that reflects the light is irradiated with the light, it is perpendicular to the reflective medium. By providing a light source or a display device capable of providing polarized light in the visible range so that polarized light in a directional direction is incident, the human eye may misrecognize it or a safety device that recognizes light or motion may misidentify it. It can prevent malfunction. In particular, the present invention is important in that misrecognition of various devices can be prevented in an environment where light reflection may occur due to a medium that reflects light. Further, according to the technique of the present invention, since it is possible to provide a light source that emits visible polarized light while having a transmittance of 90% or more, it is a light source that is transparent but can emit polarized light. Furthermore, since the light source emits polarized light in the visible region even when light in the ultraviolet region is made incident, it is possible to provide the light source or display device of the present invention which uses invisible light as a light inducing source. Further, a display device capable of providing an arbitrary image can be provided by controlling the polarization of the liquid crystal cell.

  It is preferable that the light source or the display device emits vertically polarized light even when a driver such as a polarizing light blocking plate or an automobile or a motorcycle uses a polarizing lens or polarizing sunglasses on the light receiving side. Generally, safety devices such as automobiles and drivers use absorption type polarized lenses and polarized sunglasses, but the light absorption axis of the light absorption type polarized lenses and polarized sunglasses is horizontal to the reflective medium, that is, It is a parallel direction. The reason is that the light reflected by the water surface, snow, asphalt, etc. is in the horizontal direction (S-polarized light), so that only the polarized light is absorbed and the light of the opposite axis, that is, the direction perpendicular to the reflection medium ( This is because by transmitting the P-polarized light, it is possible to obtain information in which reflection of the surrounding environment is suppressed, improve visibility, prevent misidentification, and reduce malfunction due to eye fatigue and misidentification of equipment. . If the light source or the display device of the present invention is provided, only the polarized light in the vertical direction can be provided to the surroundings. Therefore, not only the above-described antireflection effect can be provided, but also a general polarized lens or polarized sunglasses is used. Information can be provided to drivers and devices without obstructing the display. Therefore, the light source and display device of the present invention is a device that can provide accurate visual information even to a device or a driver using a general polarized lens or polarized sunglasses.

Substitution drawing for Example 3

Drawing substitute photograph of Comparative Example 3

  When the light emitted from the light-induced source is converted into polarized light or the light emitted from the light-induced source is used to emit polarized light and the medium that reflects the light is irradiated with the light, it is perpendicular to the reflective medium. It is a light source or a display device capable of providing polarized light in the visible region so that polarized light in a direction is incident. It should be noted that the horizontal direction or the vertical direction of the present application does not indicate an infinitely accurate angle, for example, 0 ° or 90 °, but merely indicates a rough direction thereof. Specifically, when the vertical direction is 0 ° or the horizontal direction is 90 °, the effect of the present application is exhibited even if the angle is different from each other by about ± 10 °.

  It is generally known that light is reflected by a medium that reflects light, and the reflected light has a polarization. For example, when the incident light makes an angle of 30 ° to 80 ° with the medium that reflects the light, the light that is reflected and visible has a relatively strong polarization. Generally, when the angle is called the Brewster's angle, the light in the direction perpendicular to the reflective medium has significantly less reflection, and the ratio of the light polarized in the horizontal direction to the reflective medium is larger than that of the reflected light. Grows. That is, although the reflected light has a polarized light, the present application provides a light source or a display device utilizing this phenomenon, and a light source capable of emitting the polarized light so as to be incident in a direction perpendicular to a medium that reflects light. By doing so, it is possible to provide a light source capable of suppressing light reflection and a display device using the same.

  The angle formed between the light source or the display device of the present application and the medium that reflects light is not particularly limited, and the light source or the display device can be arranged at any angle. The angle between the light emitted from the light source or the display device (light emission) and the medium that reflects the light is 30 ° to 85 ° when the vertical direction to the reflective medium is 0 °. Better, but preferably 40 ° to 80 °, more preferably 50 ° to 75 °. It is not necessary that the total amount of light emitted from the light source or the display device of the present application is in the range of 30 ° to 85 °, and a part of the light incident on the reflection medium is emitted in the angle range to reflect the light. A light source or display device that can be reduced or suppressed can be achieved.

  The above-mentioned medium that reflects light is, for example, water, snow, ice, stone, other than those existing in a natural environment such as leaves, metal such as silver, aluminum, copper, iron, mirror, plastic, marble, asphalt, Examples thereof include paper and glass, and examples include asphalt and plastic to which water, snow, ice, etc. adhere, and the medium is not particularly limited as long as it can reflect light.

  In order to realize the light source or the display device used in the present invention, a light-induced source for emitting the light is required, and the light from the light-induced source is converted into polarized light, or the light from the light-induced source is used. It is necessary to emit polarized light by utilizing. The light of the light source used in the present application or the light of the light-inducing source capable of making light incident on the display device is not particularly limited as long as it can emit light, and examples thereof include an LED lamp, a white light bulb, a xenon lamp, and an ultraviolet lamp. A mercury lamp or the like can be used and is not particularly limited. The light inducing source used in the present invention may be a general light emitting device as long as it can emit light. As a general light emitting device, for example, a device capable of emitting light and displaying an image or the like, such as a liquid crystal display, an OLED, an FED, a CRT, an LED display, an LED micro display, can be used. The wavelength of the light from these photo-stimulation sources is not limited and may be any wavelength. For example, a photostimulation source capable of emitting light having a wavelength in the ultraviolet range, the visible range, the infrared range, or the like can be used.

  The polarization axis of polarized light emitted from the light source or display device of the present application needs to be vertically polarized light when the medium that reflects the light is horizontal. Vertically polarized light is also commonly referred to as "P-polarized light." By irradiating the light-reflecting medium with vertically polarized light, the reflected light is attenuated and the reflection of the light can be suppressed. In the present invention, in order to provide a light source or a display device that emits “P-polarized light”, which is polarized light in the visible region so that light polarized in the vertical direction is incident on a medium that reflects light, An optical element that can convert polarized light, such as a general polarizing plate, is placed on the outermost surface of the light-induced source so that the light from the induced source can be converted into polarized light, or the light emitted from the light-induced source is used. Then, the element capable of emitting polarized light (polarized light emitting element) emits polarized light in a direction perpendicular to the reflection medium, thereby achieving the embodiment of the technology of the present application.

(Polarizer)
The above-mentioned polarizing plate is not particularly limited as long as it is a polarizing plate having a function of converting the light from the light inducing source into polarized light. Preferably, it has a function of converting visible light into polarized light. Examples of the polarizing plate include iodine-based polarizing plates, dye-based polarizing plates, dye-based polarizing plates that can control the polarization of only specific wavelengths, polarizing plates using polyene, and wire grid-type polarizing plates. Is also good. The polarizing plate has a polarization performance for light in a part or the whole wavelength range of 400 to 700 nm. Examples of iodine-based polarizing plates include those described in JP 2001-290029 A, JP 2010-072548 A, and the like, and examples of dye-based polarizing plates include JP 2001-033627 A and JP 2004-251962. Examples of the dye-based polarizing plate capable of controlling the polarization of only a specific wavelength include those described in JP 2007-084803 A, JP 2007-238888 A, and the like. Examples of the polarizing plate using polyene include those described in JP 2005-527847 A, JP 2005-517974 A, and the like, and as a wire grid type polarizer, JP 2003-518818 A. And those described in Japanese Patent Publication No. 2003-502708. Examples of the reflective polarizing plate include U.S. Pat. Nos. 3,610,729, WO95 / 17303, WO95 / 17692, WO95 / 17699, WO96 / 19347, WO99 / 36262, WO2005 / 0888363, and JP2007-298634A. Examples thereof include those described in WO2011 / 074701, and examples of the product include DBEF (manufactured by 3M Company). Further, it is preferable to use a reflective polarizing plate as the polarizing plate because not only can uniaxial linearly polarized light be transmitted, but also polarized light of different axes can be reflected to the inside and reused. Therefore, the use of the reflective polarizing plate as the polarizing plate is mentioned as one preferable mode of the present invention. Further, the light source or the display device of the present invention is achieved by arranging each of the above-mentioned polarizing plates in the light inducing source so that the light incident on the reflection medium becomes the light polarized in the vertical direction (P-polarized light). Therefore, it can be mentioned as one preferable form.

  In order to achieve the function of the present application, it is preferable to arrange the polarizing plate so that the polarization axis of the polarizing plate is perpendicular to the reflection medium, that is, the P-polarized light is emitted to the reflection medium. However, as a form of a polarizing plate whose polarization axis is perpendicular to the reflective medium, that is, which can provide P-polarized light to the reflective medium, the absorption axis of an iodine-based polarizing plate or a dye-based polarizing plate is defined as a reflective medium. Can be achieved by arranging the absorption axis of the polarizing plate in a horizontal direction, that is, in a direction parallel to the reflection medium. By arranging the absorption axis of the iodine-based polarizing plate or the dye-based polarizing plate in the horizontal direction, only the vertically polarized light is transmitted, and the vertical light is suppressed from being reflected. A device may be provided.

  As a more preferable form, it is preferable to use an element that emits polarized light in the visible light region at the time of display, instead of using an absorption type or birefringence type polarizing plate. An element that emits polarized light in the visible light region may be abbreviated as “polarized light emitting element” in the present application.

  The polarized light-emitting element refers to an element that emits polarized light in the visible range by irradiating the element with light in the ultraviolet range to the visible range from a light-induced source, and utilizes the function of the device to emit light. It can be used or used as a display device. Since the direction of polarized light emitted from the device is a wave (P-polarized light) perpendicular to the reflection medium, specifically, perpendicular to the reflection medium, a light source or display using the light source is performed. You can get the device.

  It is more preferable that the polarized light emitting element has a high light transmittance because not only a display emitting polarized light but also information passing through the element can be obtained. A display device having such a characteristic that both transparency and display are compatible with each other is called a transparent display or a see-through display, and it is possible to visually recognize the background through the display in addition to the displayed information. For example, by providing a sign, a signboard, or a general display device behind a light source or a display device that emits light in a direction (P-polarized light) perpendicular to the reflective medium of the present invention, the information is provided to people and equipment. However, light that suppresses reflection from the light source or the display device can be provided.

  It is preferable that the polarized light emitting element has high light transparency, but the transparency is not limited. Generally, having a transmittance of 40% to 100% makes it easy to visually recognize the background through the medium. Therefore, for example, the light transmittance of the light source or the display device is 40% or more and 100% or more. It is preferably below, for example, if it is 50% or more, it functions well as a device for providing background information, preferably 60% or more, more preferably 70% or more, further preferably 80% or more, particularly preferably 85% or more is good.

  As a method for maintaining the transparency of the polarized light emitting device, it is preferable that the device emits polarized light in the visible range but absorbs all or part of the light in the visible range of 380 to 780 nm. It is preferable to obtain a polarized light emitting element that emits polarized light in the visible range by utilizing light in the visible range of ultraviolet to near-ultraviolet. It should be noted that emitting light in the visible range by utilizing light in the ultraviolet to near-ultraviolet visible range from a light-induced source is generally called fluorescence emission or phosphorescence emission, and in the present application, the emitted light is polarized. It is preferably fluorescent emission.

  As one of preferred forms of an element (polarized light emitting element) that emits visible light using light in the ultraviolet to near-ultraviolet visible range, for example, in the light wavelength region, light having a wavelength shorter than 430 nm is used. It is an element that absorbs light in the range of near-ultraviolet visible region and emits polarized light having an emission spectrum peak in a part or all of the visible region of 380 nm to 780 nm, and a base material and polarized luminescent dyes described below. Including at least. With respect to the light in the ultraviolet to near-ultraviolet visible range, which is irradiated for causing the polarized light emitting element to emit polarized light, light of 300 to 430 nm can be preferably used, but invisible light or a wavelength at which eye sensitivity is extremely low. It is preferable to use the above light. Therefore, it is preferable to use light of 340 to 415 nm, more preferably 350 to 400 nm, and particularly preferably 350 to 390 nm. Irradiated light in the ultraviolet to near-ultraviolet visible region may or may not have polarized light and may have polarized light. The light in the ultraviolet to near-ultraviolet visible range with which the polarized light emitting element is irradiated may be a general light-inducing source such as an LED, or natural light including light in the ultraviolet to near-ultraviolet visible range, for example, sunlight.

<Substrate>
The polarized light emitting device uses a polymer film as a base material for adsorbing and orienting a polarized light emitting dye described later. The polymer film is preferably a hydrophilic film obtained by forming a hydrophilic polymer capable of adsorbing a polarized light-emitting dye having general dichroism, particularly a dye having a stilbene skeleton or a dye having a biphenyl skeleton. Polymer film is good. The hydrophilic polymer is not particularly limited, but, for example, a polyvinyl alcohol-based resin or a starch-based resin is preferable, and the polyvinyl alcohol-based resin is preferable from the viewpoints of the dyeability, processability and cross-linking property of the dichroic polarized light-emitting dye. It is preferably a resin or a derivative thereof. Examples of the polyvinyl alcohol-based resin and its derivative include, for example, polyvinyl alcohol or its derivative, and an olefin such as ethylene or propylene, or an unsaturated olefin such as crotonic acid, acrylic acid, methacrylic acid, and maleic acid. Examples thereof include those modified with saturated carboxylic acid and the like. Among them, a film made of polyvinyl alcohol or a derivative thereof is preferably used from the viewpoint of the adsorptivity and orientation of the dichroic polarized luminescent dye. As the base material, for example, a film made of a commercially available polyvinyl alcohol-based resin or a derivative thereof may be used, or may be produced by forming a film of the polyvinyl alcohol-based resin. The method for forming the polyvinyl alcohol-based resin film is not particularly limited, and examples thereof include a method for melt-extruding hydrous polyvinyl alcohol, a casting film forming method, a wet film forming method, and a gel film forming method (once cooling the polyvinyl alcohol aqueous solution. After gelation, the solvent is extracted and removed), a cast film-forming method (flowing an aqueous polyvinyl alcohol solution on a substrate and drying), and a combination of these methods can be used. The thickness of the substrate is usually 10 to 100 μm, preferably about 20 to 80 μm.

<Method of manufacturing polarized light emitting element>
The method for manufacturing the above polarized light emitting device is not limited to the following manufacturing method, but it is preferable to mainly use a film made of polyvinyl alcohol or a derivative thereof. A method for producing a polarized light emitting device will be described by taking the case of using a film made of polyvinyl alcohol or a derivative thereof as an example.

  The method for producing the polarized light-emitting device includes a step of preparing a base material, a swelling step of immersing the base material in a swelling liquid to swell the base material, and the swelled base material with one or more of the polarized light emitting dyes. In a dyeing solution containing at least a dye, and a dyeing step of adsorbing a polarized light emitting dye on the substrate, and dipping the substrate having the polarized light emitting dye adsorbed in a solution containing boric acid into the substrate. A cross-linking step of cross-linking, a stretching step of uniaxially stretching the polarized light-emitting dye cross-linked substrate in a certain direction to arrange the polarized light-emitting dye in a certain direction, and if necessary, the stretched substrate with a cleaning liquid. A production method including a washing step of washing and / or a drying step of drying the washed substrate will be exemplified and described below.

(Swelling process)
The swelling step will be described. The swelling step is preferably performed by immersing the substrate in a swelling liquid at 20 to 50 ° C. for 30 seconds to 10 minutes, and the swelling liquid is preferably water. The draw ratio of the base material with the swelling liquid is preferably adjusted to 1.00 to 1.50 times, and more preferably 1.10 to 1.35 times.

(Dyeing process)
The dyeing step will be described. One or more polarized luminescent dyes described below are adsorbed on the substrate obtained through the swelling step. The dyeing step is not particularly limited as long as it is a method capable of adsorbing a polarized light emitting dye on a substrate, for example, a method of immersing the substrate in a dyeing solution containing a polarized light emitting dye, or a substrate Examples thereof include a method of applying a dyeing solution containing a polarized light emitting dye, and a method of immersing in a dyeing solution containing a polarized light emitting dye is preferable. The concentration of the polarized light emitting dye in the dyeing solution is not particularly limited as long as the polarized light emitting dye is sufficiently adsorbed in the substrate, but is, for example, 0.0001 to 1 mass% in the dyeing solution. It is preferable that it is 0.0001 to 0.5% by mass. The temperature of the dyeing solution in the dyeing step is preferably 5 to 80 ° C, more preferably 20 to 50 ° C, particularly preferably 40 to 50 ° C. Further, the time for immersing the substrate in the dyeing solution can be appropriately adjusted, and is preferably adjusted within 30 seconds to 20 minutes, more preferably within 1 to 10 minutes. The polarized light-emitting dye contained in the dyeing solution may be used alone or in combination of two or more. Since the polarized luminescent dyes have different luminescent colors due to differences in dye structure, etc., it is necessary to appropriately adjust the luminescent color to be generated by adding plural kinds of the polarized luminescent dyes to the substrate. You can In addition, the dyeing solution may further contain one or more kinds of organic dyes and / or fluorescent dyes, if necessary.

(Polarized luminescent dye)
The polarized luminescent dye is a compound having at least one of a stilbene skeleton and a biphenyl skeleton in the structure and emitting fluorescence, or a salt thereof. The polarized light-emitting dye can emit polarized light by having a dichroic ratio while having fluorescent light emission. In particular, a polarized light emitting dye having a stilbene skeleton or a biphenyl skeleton has both excellent fluorescent emission characteristics and a characteristic of having a high dichroic ratio when oriented. These characteristics are derived from each of the above skeletons, and further improve these characteristics, or to adjust various characteristics such as absorption wavelength, emission wavelength, various fastnesses such as light resistance, moisture resistance, ozone gas resistance, solubility, etc. It is possible to further introduce arbitrary substituents into the skeleton. When introducing this substituent, depending on the type and position of the substituent, although it is possible to achieve a high degree of polarization like conventional dye-based polarizing plates, the amount of emitted light is significantly reduced, and thus the fluorescence emission characteristics are excellent, and In order to have a high dichroic ratio, it is important to select the type of substituent and the substitution position. In addition, the above polarized luminescent dyes may be used alone or in combination of two or more.

(A) Dye Having Stilbene Skeleton The dye having a stilbene skeleton is preferably a compound represented by the formula (1) or a salt thereof.

  In the above formula (1), L and M may each independently have a nitro group, an amino group which may have a substituent, a carbonylamide group which may have a substituent, and a substituent. Naphthotriazole group, alkyl group having 1 to 20 carbon atoms which may have a substituent, vinyl group which may have a substituent, amide group which may have a substituent, and which may have a substituent It represents a good ureido group, an aryl group which may have a substituent, and a carbonyl group which may have a substituent, but is not necessarily limited thereto. It is known that a dye having a stilbene skeleton represented by the formula (1) has fluorescence emission and can obtain dichroism by being oriented. This is mainly due to the stilbene skeleton. In addition, any substituent may be introduced. However, when the stilbene skeleton has an azo group at the L position and the M position, fluorescence emission is significantly reduced, which is not preferable.

  Examples of the amino group which may have a substituent include an unsubstituted amino group, a methylamino group, an ethylamino group, an n-butylamino group, a tert-butylamino group, an n-hexylamino group and a dodecylamino group. Group, dimethylamino group, diethylamino group, di-n-butylamino group, ethylmethylamino group, ethylhexylamino group, and the like, optionally substituted alkylamino group having 1 to 20 carbon atoms, phenylamino group, diphenyl Substitution of arylamino group, methylcarbonylamino group, ethylcarbonylamino group, n-butyl-carbonylamino group and the like which may have a substituent such as amino group, naphthylamino group and N-phenyl-N-naphthylamino group C1-C20 alkylcarbonylamino group which may have a group, phenylcarbonylamino group, biphenyl Carbon number such as arylcarbonylamino group which may have a substituent such as carbonylamino group, naphthylcarbonylamino group, methylsulfonylamino group, ethylsulfonylamino group, propylsulfonylamino group, n-butyl-sulfonylamino group, etc. To arylsulfonylamino which may have a substituent such as an alkylsulfonylamino group having 20 to 20 carbon atoms, a phenylsulfonylamino group, and a naphthylsulfonylamino group, etc., and an alkyl having 1 to 20 carbon atoms which may have a substituent. It is preferably a carbonylamino group, an arylcarbonylamino group which may have a substituent, an alkylsulfonylamino group having 1 to 20 carbon atoms, or an arylsulfonylamino group which may have a substituent. Moreover, the C1-C20 alkylamino group which may have the said substituent, the arylamino group which may have a substituent, the C1-C20 alkylcarbonylamino which may have a substituent. The group, the arylcarbonylamino group which may have a substituent, the alkylsulfonylamino group having 1 to 20 carbon atoms, the substituent in the arylsulfonylamino group which may have a substituent are not particularly limited, Examples thereof include a nitro group, a cyano group, a hydroxyl group, a sulfonic acid group, a phosphoric acid group, a carboxy group, a carboxyalkyl group, a halogen atom, an alkoxyl group and an aryloxy group.

  Examples of the carboxyalkyl group include a methylcarboxy group and an ethylcarboxy group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. Examples of the alkoxyl group include a methoxy group, an ethoxy group and a propoxy group. Examples of the aryloxy group include a phenoxy group and a naphthoxy group.

As good carbonylamido group optionally having the above substituent, for example, N- methyl - carbonyl amide group (-CONHCH _3), N- ethyl - carbonyl amide group (-CONHC ₂ H _5), N- phenyl - carbonyl and amide group (-CONHC ₆ H ₅₎ can be mentioned.

  Examples of the naphthotriazole group which may have a substituent include a benzotriazole group and a naphthotriazole group.

  Examples of the alkyl group having 1 to 20 carbon atoms which may have a substituent include direct groups such as methyl group, ethyl group, n-butyl group, n-hexyl group, n-octyl group and n-dodecyl group. Examples thereof include a branched chain alkyl group such as a chain alkyl group, an isopropyl group, a sec-butyl group and a tertiary butyl group, and a cyclic alkyl group such as a cyclohexyl group and a cyclopentyl group.

  Examples of the vinyl group which may have a substituent include a vinyl group, a methylvinyl group, an ethylvinyl group, a divinyl group, and a pentadiene group.

As good amido group optionally having the above substituent, for example, acetamide group (-NHCOCH _3), such as benzamido group (-NHCOC ₆ H ₅₎ can be mentioned.

  Examples of the aryl group that may have a substituent include a phenyl group, a naphthyl group, a proposed toracenyl group, and a biphenyl group.

  Examples of the carbonyl group which may have a substituent include a methylcarbonyl group, an ethylcarbonyl group, an n-butyl-carbonyl group and a phenylcarbonyl group.

  The above-mentioned optionally substituted carbonylamide group, optionally substituted naphthotriazole group, optionally substituted C1-20 alkyl group, optionally substituted As a substituent in a vinyl group, an amide group which may have a substituent, an ureido group which may have a substituent, an aryl group which may have a substituent, and a carbonyl group which may have a substituent Is not particularly limited, but may be the same as the substituent described in the above-mentioned amino group which may have a substituent.

  The dye having a stilbene skeleton represented by the above formula (1) is particularly preferably a dye represented by the following formula (2) or a salt thereof, or a dye represented by the following formula (3) or a salt thereof. The use of these dyes is preferable because a polarized light emitting device that emits clear white light can be obtained.

  In the above formula (2), the substituent R is a hydrogen atom, a chlorine atom, a bromine atom, or a halogen atom such as a fluorine atom, a hydroxyl group, a carboxy group, a nitro group, an alkyl group which may have a substituent, or a substituent. It represents an alkoxyl group which may have or an amino group which may have a substituent. The alkyl group which may have a substituent may be the same as the alkyl group having 1 to 20 carbon atoms which may have a substituent. The alkoxyl group which may have a substituent is preferably a methoxy group, an ethoxy group or the like. The amino group which may have a substituent may be the same as above, and is preferably a methylamino group, a dimethylamino group, an ethylamino group, a diethylamino group, a phenylamino group or the like. The substituent R may be bonded to any carbon of the naphthalene ring in the naphthotriazole ring, but is preferably 3 position, 5 position when the carbon condensed with the triazole ring is the 1st position and the 2nd position. It is bonded to the 8th or 8th position.

In the above formula (2), n is an integer of 0 to 3, preferably 1 to 2. In the above formula (2), the — (SO ₃ H) group may be bonded to any carbon of the naphthalene ring in the naphthotriazole ring. The substitution position of the — (SO ₃ H) group on the naphthalene ring is, when n = 1, when the carbon condensed with the triazole ring is the 1-position and the 2-position, the 4-position, the 6-position, or the 7-position. Is preferable, and when n = 2, the 5th and 7th positions are preferable, and when 6th and 8th position is preferable, when n = 3, the 3rd, 6th and 8th positions are combinations. Is preferred. Further, it is particularly preferable that R is a hydrogen atom and n is 1.

  X in the above formula (2) represents a nitro group or an amino group which may have a substituent, and is preferably a nitro group. The amino that may have a substituent may be the same as described above, an alkylcarbonylamino group having 1 to 20 carbon atoms that may have a substituent, an arylcarbonylamino group that may have a substituent, It is preferably an alkylsulfonylamino group having 1 to 20 carbon atoms or an arylsulfonylamino group which may have a substituent.

  Y in the above formula (3) represents an alkyl group having 1 to 20 carbon atoms which may have a substituent, a vinyl group which may have a substituent, or an aryl group which may have a substituent. It is preferably an aryl group which may have a substituent, more preferably a naphthyl group which may have a substituent, and a naphthyl group in which an amino group and a sulfo group are substituted as a substituent. Is particularly preferable.

  Z in formula (3) represents the same substituent as described for X in formula (2) above, and is preferably a nitro group.

  Examples of the compound represented by the formula (1) include the Kayaphor series (manufactured by Nippon Kayaku Co., Ltd.) and the Whitex series (manufactured by Sumitomo Chemical Co., Ltd.) such as Whitex RP. Further, the compound represented by the formula (1) is exemplified below, but the compound is not limited to these.

(B) Dye having a biphenyl skeleton The dye having a biphenyl skeleton is preferably a compound represented by the formula (4) or a salt thereof.

  In the above formula (4), P and Q may each independently have a nitro group, an amino group which may have a substituent, a carbonylamide group which may have a substituent, and a substituent. Naphthotriazole group, alkyl group having 1 to 20 carbon atoms which may have a substituent, vinyl group which may have a substituent, amide group which may have a substituent, and which may have a substituent It represents a good ureido group, an aryl group which may have a substituent, a carbonyl group which may have a substituent, or an amino group which may have a substituent, but is not necessarily limited thereto. However, having an azo group at the P position and / or the Q position of the biphenyl skeleton is not preferable because the fluorescence emission becomes extremely small.

  The compound represented by the above formula (4) is preferably a compound represented by the following formula (5).

In the above formula (5), j represents an integer of 0 to 2. The preferred substitution position of the (SO ₃ H)-group is not particularly limited, but when the vinyl group is the 1st position, the 2nd position, the 4th position and the 6th position are preferable, and the 2nd position or the 4th position is particularly preferable.

In the above formula (5), R ₁ , R ₂ , R ₃ , and R ₄ are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxyl group having 1 to 4 carbon atoms, an aralkyloxy group, or an alkenyloxy group. A group, an alkylsulfonyl group having 1 to 4 carbon atoms, an arylsulfonyl group having 6 to 20 carbon atoms, a carbonamido group, a sulfonamide group, and a carboxyalkyl group. The carboxyalkyl group may be the same as above.

  Examples of the alkyl group having 1 to 4 carbon atoms include a methyl group, an ethyl group, a propyl group, an n-butyl group, a sec-butyl group, a tert-butyl group and a cyclobutyl group.

  Examples of the alkoxy group having 1 to 4 carbon atoms include a methoxy group, an ethoxy group, a propoxy group, an n-butoxy group, a sec-butoxy group, a tert-butoxy group and a cyclobutoxy group.

  Examples of the aralkyloxy group include aralkyloxy groups having 7 to 18 carbon atoms.

  Examples of the alkenyloxy group include an alkenyloxy group having 1 to 18 carbon atoms.

  Examples of the alkylsulfonyl group having 1 to 4 carbon atoms include a methylsulfonyl group, an ethylsulfonyl group, a propylsulfonyl group, an n-butylsulfonyl group, a sec-butylsulfonyl group, a tert-butylsulfonyl group and a cyclobutylsulfonyl group. To be

  Examples of the arylsulfonyl group having 6 to 20 carbon atoms include a phenylsulfonyl group, a naphthylsulfonyl group and a biphenylsulfonyl group.

In the above formula (5), the preferred substitution positions of R _{1 to} R ₄ are preferably the 2-position, 4-position and 6-position when the vinyl group is the 1-position.

  A method for synthesizing the polarized light-emitting dye represented by the above formula (5) will be described below. The polarized light-emitting dye represented by the formula (5) can be produced by a known method, but for example, it can be obtained by condensing 4-nitrobenzaldehyde-2-sulfonic acid with a phosphonate and then reducing the nitro group.

  The compound represented by the formula (5) is exemplified by the following compounds described in JP-A-4-226162.

The salts of the compounds represented by the above formulas (1) to (5) are salts formed with an inorganic cation or an organic cation. Examples of the inorganic cations include cations such as alkali metals, such as lithium, sodium, and potassium, and ammonium ions (NH ₄ ⁺ ). Examples of the organic cation include organic ammonium represented by the following formula (D).

In formula (D), Z ₁ to Z ₄ each independently represent a hydrogen atom, alkyl, hydroxyalkyl, or hydroxyalkoxyalkyl, and at least one of Z _{1 to} Z ₄ is a group other than a hydrogen atom.

Specific examples of Z _{1 to} Z ₄ include C ₁ -C ₆ alkyl such as methyl, ethyl, butyl, pentyl, and hexyl, preferably C ₁ -C ₄ alkyl; hydroxymethyl, 2-hydroxyethyl, 3-hydroxy. Hydroxy C ₁ -C ₆ alkyl such as propyl, 2-hydroxypropyl, 4-hydroxybutyl, 3-hydroxybutyl, and 2-hydroxybutyl, preferably hydroxy C ₁ -C ₄ alkyl; and hydroxyethoxymethyl, 2-hydroxy. Hydroxy C ₁ -C ₆ alkoxy C ₁ -C ₆ alkyl such as ethoxyethyl, 3-hydroxyethoxypropyl, 3-hydroxyethoxybutyl, and 2-hydroxyethoxybutyl, preferably hydroxy C ₁ -C ₄ alkoxy C ₁ -C. _4- alkyl etc. are mentioned.

  Among these inorganic cations and organic cations, more preferred are cations such as sodium, potassium, lithium, monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine, and ammonium. Ions are mentioned. Among these, lithium ion, ammonium ion, and sodium ion are more preferable.

In addition, as the polarized light emitting dye that can be used in the polarized light emitting element, for example,
C. I. Fluorescent Brighter 5,
C. I. Fluorescent Brighter 8,
C. I. Fluorescent Brighter 12,
C. I. Fluorescent Brighter 28,
C. I. Fluorescent Brighter 30,
C. I. Fluorescent Brighter 33,
C. I. Fluorescent Brighter 350,
C. I. Fluorescent Brighter 360,
C. I. Fluorescent Brighter 365,
And the like. These fluorescent dyes may be a free acid or an alkali metal salt (for example, Na salt, K salt, Li salt), ammonium salt or salt of amines.

A polarized light emitting element that emits polarized light can be obtained by orienting one type or a combination of two or more types of the polarized light emitting dyes obtained above. When two or more types of polarized light emitting dyes are used in the polarized light emitting device, it is possible to adjust various emission colors by adjusting the mixing ratio between the polarized light emitting dyes. For example, the polarized light emitted from the polarized light emitting element can be made white by adjusting the absolute values of the chromaticity a ^* value and the b ^* value to be 5 or less. The chromaticity a ^* value and b ^* value are obtained according to JIS Z 8781-4: 2013 based on the spectral distribution measured for the light emitted from the polarized light emitting element when the light is incident on the polarized light emitting element. To be The object color display method defined in JIS Z 8781-4: 2013 corresponds to the object color display method defined by the International Commission on Illumination (abbreviation "CIE"). The measurement of chromaticity a ^* value and b ^* value is usually performed by irradiating a measurement sample with natural light. However, in the specification and claims of the present application, a polarized light emitting device has a short wavelength such as an ultraviolet light region. The chromaticity a ^* value and b ^* value can be confirmed by irradiating the above-mentioned light and measuring the emitted light. The absolute value of a ^* of the emitted light is 5 or less, preferably 4 or less, more preferably 3 or less, further preferably 2 or less, particularly preferably 1 or less. The absolute value of b ^* of the emitted light is 5 or less, preferably 4 or less, more preferably 3 or less, still more preferably 2 or less, and particularly preferably 1 or less. If the absolute values of the a ^* value and the b ^* value are independently 5 or less, it can be sensed as white by human eyes, and if both are 5 or less, more preferred white light emission is sensed. You can Since the polarized light emitted is white, it can be used as a natural light source such as sunlight, or as a light source having a paper white color, and the application is simple even when placed on a display using a color filter or the like. There is. Regarding the emission intensity, there is no problem in applying it to a display as long as it can sense that it is glowing. In particular, as features of the present application, it is important that the emitted light has a high degree of polarization and that the transmittance in the visible light region be high.

(2) Other Dyes The polarized light emitting device includes, in addition to a dye or a salt thereof having a stilbene skeleton or a biphenyl skeleton, singly or in a plurality, for the purpose of color adjustment and the like within a range not impairing the polarized light emitting function. If necessary, one or more other organic dyes or other fluorescent dyes may be further contained. Other organic dyes are not particularly limited, but those having high dichroism are preferable, and dyes having little influence on the optical characteristics of the dye having a stilbene skeleton or a biphenyl skeleton are preferable. Other organic dyes include, for example, C.I. I. Direct Yellow 12, C.I. I. Direct Yellow 28, C.I. I. Direct Yellow 44, 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 247, C.I. I. Direct Blue 69, C.I. I. Direct Blue 78, C.I. I. Direct Green 80, and C.I. I. Direct Green 59 and the like can be mentioned. These organic dyes may be free acids, or may be alkali metal salts (for example, Na salt, K salt, Li salt), ammonium salts or salts of amines.

  When the other organic dye or the other fluorescent dye is used in combination, it is possible to select the dye to be mixed and adjust the mixing ratio and the like in order to adjust the desired color of the polarized light emitting element. Depending on the purpose of preparation, the mixing ratio of the organic dye or the fluorescent dye is not particularly limited, but generally, the total amount of these other organic dyes or other fluorescent dyes relative to 100 parts by mass of the polarized light emitting device. Is preferably used in the range of 0.01 to 10 parts by mass.

  The dyeing solution may further contain a dyeing aid, if necessary, in addition to the above dyes. Examples of the dyeing aid include sodium carbonate, sodium hydrogen carbonate, sodium chloride, sodium sulfate (Glauber's salt), anhydrous sodium sulfate, sodium tripolyphosphate, and the like, and preferably sodium sulfate. The content of the dyeing aid can be arbitrarily adjusted by the above-mentioned immersion time based on the dyeability of the dye used and the temperature of the dyeing solution, etc., but it is 0.0001 to 10% by mass in the dyeing solution. It is more preferably 0.0001 to 2% by mass.

  After the dyeing step, a preliminary washing step can be optionally performed in order to remove the dyeing solution attached to the surface of the base material in the dyeing step. By passing through the preliminary washing step, it is possible to prevent the dye remaining on the surface of the substrate from being transferred to the liquid to be treated next. In the preliminary cleaning step, water is generally used as the cleaning liquid. As for the cleaning method, it is preferable to immerse the dyed substrate in the cleaning liquid, and it is also possible to perform cleaning by applying the cleaning liquid to the substrate. The washing time is not particularly limited, but is preferably 1 to 300 seconds, more preferably 1 to 60 seconds. The temperature of the cleaning liquid in the preliminary cleaning step needs to be a temperature at which the material forming the substrate is not dissolved, and the cleaning treatment is generally performed at 5 to 40 ° C. It should be noted that the performance of the polarized light emitting element is not particularly affected even without the preliminary cleaning step, and therefore the preliminary cleaning step can be omitted.

(Crosslinking process)
After the dyeing step or the pre-washing step, the substrate may contain a crosslinking agent. The method of incorporating the cross-linking agent into the base material is preferably to immerse the base material in the treatment solution containing the cross-linking agent, while the treatment solution may be applied or applied to the base material. A solution containing boric acid is used as the crosslinking agent in the treatment solution. The solvent in the treatment solution is not particularly limited, but water is preferable. The concentration of boric acid in the treatment solution is preferably 0.1 to 15% by mass, and more preferably 0.1 to 10% by mass. The temperature of the treatment solution is preferably 30 to 80 ° C, more preferably 40 to 75 ° C. Further, the processing time of this crosslinking step is preferably 30 seconds to 10 minutes, more preferably 1 to 6 minutes. Since the method for producing a polarized light emitting device according to the present invention has this cross-linking step, the obtained polarizing device has a high degree of polarization of emitted light and exhibits a high contrast as a display body. This is an excellent action that cannot be expected from the function of boric acid used in the prior art for the purpose of improving water resistance or light transmission. Further, in the crosslinking step, if necessary, a fixing treatment may be further performed with an aqueous solution containing a cationic polymer compound. By the fixing treatment, the dye can be fixed in the polarized light emitting device. At this time, as the cationic polymer compound, for example, cation, dicyanamide and formalin polymerization condensate as a dicyan system, dicyandiamide / diethylenetriamine polycondensate as a polyamine system, epichlorohydrin / dimethylamine addition polymer as a polycation system, dimethyl A diallylammonium chloride / dioxide ion copolymer, a diallylamine salt polymer, a dimethyldiallylammonium chloride polymer, an allylamine salt polymer, a dialkylaminoethyl acrylate quaternary salt polymer and the like are used.

(Stretching process)
After passing through the crosslinking step, a stretching step is performed. The stretching step is performed by uniaxially stretching the substrate in a fixed direction, and may be either a wet stretching method or a dry stretching method. The stretching ratio is preferably 3 times or more, and more preferably 5 to 8 times.

  In the wet stretching method, it is preferable to stretch the substrate in water, a water-soluble organic solvent or a mixed solution thereof. More preferably, the stretching treatment is performed while immersing the substrate in a solution containing at least one crosslinking agent. As the cross-linking agent, for example, boric acid in the cross-linking agent step can be used, and preferably the stretching treatment can be performed in the treatment solution used in the cross-linking step. The stretching temperature is preferably 40 to 70 ° C, more preferably 45 to 60 ° C. The stretching time is usually 30 seconds to 20 minutes, preferably 2 to 7 minutes. The wet stretching process may be performed in one stage or in multiple stages of two or more stages. The stretching treatment may be optionally performed before the dyeing step, and in this case, the dye orientation can be performed together with the dyeing.

  In the dry stretching method, when the stretching heating medium is an air medium, it is preferable to stretch the substrate at a temperature of the air medium from room temperature to 180 ° C. Further, the humidity is preferably in an atmosphere of 20 to 95% RH. Examples of the method for heating the base material include, but are not limited to, inter-roll zone stretching method, roll heating stretching method, hot pressure stretching method, and infrared heating stretching method. The dry stretching process may be performed in one stage or in multiple stages of two or more stages.

(Washing process)
During the stretching step, the cross-linking agent may be deposited or foreign matter may adhere to the surface of the base material, so that a cleaning step for cleaning the surface of the base material can be performed. The cleaning time is preferably 1 second to 5 minutes. As for the cleaning method, it is preferable to immerse the base material in the cleaning liquid, while the cleaning liquid may be applied to or applied to the base material to be cleaned. Water is preferable as the cleaning liquid. The cleaning treatment may be carried out in one step or in a multi-step treatment of two or more steps. The temperature of the washing solution in the washing step is not particularly limited, but is usually 5 to 50 ° C, preferably 10 to 40 ° C, and may be room temperature.

  As the solvent of the solution or treatment liquid used in each of the above-mentioned steps, in addition to the water, for example, dimethyl sulfoxide, N-methylpyrrolidone, methanol, ethanol, propanol, isopropyl alcohol, glycerin, ethylene glycol, propylene glycol, diethylene glycol. , Alcohols such as triethylene glycol, tetraethylene glycol or trimethylolpropane, amines such as ethylenediamine and diethylenetriamine, and the like. The solvent of the solution or treatment liquid is not limited to these, but is most preferably water. Moreover, the solvent of these solutions or a processing liquid may be used individually by 1 type, and may use 2 or more types of mixture.

(Drying process)
After the washing process, the base material is dried. The drying treatment can be carried out by natural drying, but in order to further improve the drying efficiency, it can be carried out by compression with a roll, removal of surface water by an air knife or a water-absorbing roll, and the like. It is also possible to do so. The temperature of the drying treatment is preferably 20 to 100 ° C, more preferably 60 to 100 ° C. The drying time is preferably 30 seconds to 20 minutes, more preferably 5 to 10 minutes.

  The polarized light emitting device according to the present invention can be manufactured by the above method. The polarized light emitting element according to the present invention is an element that exhibits polarized light emission and polarized light in the ultraviolet region, and has high durability because the dichroic dye does not decompose even in a high temperature and high humidity heat environment.

  When the polarized light emitting device is irradiated with light in the ultraviolet range to the visible range, particularly light in the ultraviolet range to the near-ultraviolet range, it emits polarized light in the visible range using its energy. Since the light emitted by the polarized light emitting element is polarized light in the visible range, when observing the polarized light emitting element through a general polarizing plate having a polarization function for light in the visible range, the visible light range is By changing the angle of the axis of a general polarizing plate having a polarizing function, it is possible to visually recognize the light of the axis that emitted polarized light and the light of the axis that emits significantly less light. The polarization degree of the light emitted by the polarized light emitting element is 70% or more, preferably 80% or more, more preferably 90% or more, further preferably 95% or more, and particularly preferably 99% or more. Further, a polarized light emitting element using a polarized light emitting dye having a biphenyl skeleton or a stilbene skeleton transmits light in the visible range, and thus has high transmittance. If the transmittance of light in the visible region of the polarized light emitting element is 50% or more in the transmittance corrected for the luminosity factor, a liquid crystal display having a significantly high transmittance can be obtained as compared with a conventional liquid crystal display. , Preferably 60% or more, more preferably 70% or more, further preferably 80% or more, particularly preferably 90% or more. Since the polarized light emitting element used in the present application has a high transmittance, absorption in the visible light region is small in the non-emission state, and a highly transparent polarized light emitting element can be obtained. Therefore, it is preferable to use the polarized light emitting element in the present invention. one of.

[Polarized light emitting plate]
A polarized light emitting plate can be obtained by providing a transparent protective layer on at least one surface of the polarized light emitting element. The transparent protective layer is used to improve the water resistance and handleability of the polarized light emitting element, and the transparent protective layer does not affect the polarization function of the polarized light emitting element.

  The transparent protective layer is preferably a transparent protective film having excellent optical transparency and mechanical strength. Further, the transparent protective layer is preferably a film having a layer shape capable of maintaining the shape of the polarized light emitting device, and is a plastic film excellent in thermal stability, moisture shielding property, etc. in addition to transparency and mechanical strength. Preferably there is. As a material for forming such a protective film, for example, a cellulose acetate film, an acrylic film, a fluorine film such as an ethylene tetrafluoride / hexafluoropropylene copolymer, or a polyester resin or a polyolefin resin. Alternatively, a film made of a polyamide resin can be used, and preferably a triacetyl cellulose (TAC) film or a cycloolefin film is used. The thickness of the transparent protective layer is preferably 1 μm to 200 μm, more preferably 10 μm to 150 μm, and particularly preferably 40 μm to 100 μm. The method for producing the above polarizing plate is not particularly limited, but for example, the polarizing plate can be produced by stacking a transparent protective layer on a polarized light emitting element and laminating it with a known formulation.

  The polarized light emitting plate may further include an adhesive layer for bonding the transparent protective layer and the polarized light emitting element between the transparent protective layer and the polarized light emitting element. The adhesive constituting the adhesive layer is not particularly limited, and examples thereof include polyvinyl alcohol adhesive, urethane emulsion adhesive, acrylic adhesive, polyester-isocyanate adhesive, and the like, and preferably A polyvinyl alcohol adhesive is used. After the transparent protective layer and the polarized light emitting device are bonded together with an adhesive, the polarized light emitting plate can be produced by performing drying or heat treatment at an appropriate temperature.

  Further, the polarized light emitting plate may appropriately include various known functional layers such as an antireflection layer, an antiglare layer, and a further transparent protective layer on the exposed surface of the transparent protective layer. When producing a layer having such various functionalities, a method of coating a material having various functionalities on the exposed surface of the transparent protective layer is preferable, and various functional layers or films are bonded via an adhesive or a pressure-sensitive adhesive. It is also possible to attach it to the exposed surface of the transparent protective layer.

  Examples of the further transparent protective layer include hard coat layers such as acrylic and polysiloxane bases, and urethane based protective layers. Further, an antireflection layer may be provided on the exposed transparent protective layer in order to further improve the single transmittance. The antireflection layer can be formed, for example, by subjecting a material such as silicon dioxide or titanium oxide to vapor deposition or sputtering treatment on the transparent protective layer, or by applying a fluorine-based material thinly on the transparent protective layer.

  By installing the polarized light emitting element or the polarized light emitted from the polarized light emitting plate so that the polarized light is emitted in the direction perpendicular to the reflection medium (emits P-polarized light), reflection can be attenuated in the reflection medium in the horizontal direction. A preferable form can be provided as the light source of the present application.

  By arranging the polarized light emitting element or the polarized light emitting plate so that polarized light is emitted in a direction perpendicular to the reflection medium, it can be utilized as a light source capable of emitting light capable of suppressing reflection. Or, it is possible to provide images and characters by processing a polarized light emitting plate or by combining with a liquid crystal cell, etc. Furthermore, by using a medium that controls the phase of polarized light, the phase of emitted polarized light can be changed. It is possible to convert not only linearly polarized light, but also light and wavelength converted into various polarized lights such as circularly polarized light and elliptically polarized light, and it becomes possible to display characters and images. Using a medium for controlling the phase together with the polarized light emitting plate is mentioned as one preferable mode of the present invention. Examples of the medium for controlling the phase include a case where a retardation plate (also called a wave plate, a retardation film or the like) is dynamically driven, or a liquid crystal cell which electrically drives and controls a liquid crystal. . In particular, it is preferable to use a liquid crystal cell capable of electrically controlling the phase as a medium for controlling the phase. Light has the properties of particles and waves, but when light is expressed as a wave, it means that the phase of the wave can be controlled. When focusing on the polarization performance, for example, a wave plate is an optical functional element that gives a predetermined phase difference to linearly polarized light, and polarization is relative to light of a specific axis in other axes (for example, 90 °). , It is possible to provide different phases. That is, by providing a retardation plate on the optical path of one polarized light, it is possible to newly provide polarized light of the opposite axis, circularly polarized light, elliptically polarized light, or the like. Therefore, the retardation plate is an element capable of changing the polarization state of incident light by making a phase difference between two orthogonal polarization components by using an oriented birefringent material (for example, a stretched film). Can be said. As a specific application of this wave plate, for example, when the wavelength of specific light is λ, by setting the slow axis of the λ / 2 retardation plate at 45 ° with respect to the axis of polarization, It is possible to rotate the linearly polarized light incident on the wave plate (phase difference plate) by 90 ° and emit it as polarized light having a polarization axis in a direction orthogonal (90 °) to the incident polarization axis. Further, when the slow axis of the λ / 4 retardation plate is set at 45 ° with respect to the polarization axis, linearly polarized light incident on the wave plate (retardation plate) may be emitted as circularly polarized light. It is possible. In recent years, a depolarizing film has been sold, and it is possible to eliminate emitted polarized light. Examples of the depolarization film include “SRF manufactured by Toyobo Co., Ltd.” and the like. The transmittance of such a retardation plate is preferably 50 to 99%, preferably 70 to 99%, more preferably 80 to 99%.

  The polarized light emitting device and the polarized light emitting plate used in the present application have absorption anisotropy in the ultraviolet to near-ultraviolet visible region, that is, have a polarizing function in the ultraviolet light region, and thus are converted into fluorescent light emission by the absorption anisotropy. The amount of light emitted from the polarized light emitting element can be controlled by the amount of absorbed light of polarized light on the irradiated axis. That is, the polarized light emitting element and the polarized light emitting plate described in the present application can control visible light emission by irradiating the absorption axis of light from the light inducing source, for example, ultraviolet polarized light, to the light of the polarized light emitting element or the polarized light emitting plate. . Specifically, the polarization axis of the light in the ultraviolet light region emitted from the light-induced source emits polarized light when the ultraviolet light absorption axis of the polarized light emitting element, and the polarized light emitting plate, coincides with the polarized light emitting element. When the polarization axis of the incident light in the ultraviolet light region is different from the ultraviolet absorption axes of the polarized light emitting element and the polarized light emitting plate, it does not emit polarized light. That is, it is preferable to use the polarized light emitting element and the polarized light emitting plate of the present application as a light source because the display can be controlled by the light in the ultraviolet region, that is, the light that does not affect the visual recognition and thus does not affect the display necessary for the visual recognition. .

  As the polarizing plate capable of controlling light in the ultraviolet region, for example, a polarizing plate using iodine or a dichroic dye described in WO 2005/015275 or the like can be used. When a layer or a film is provided to impart a protective function to the polarizing plate, it is preferable to laminate with a film having no ultraviolet absorbing ability or to provide a layer having no ultraviolet absorbing ability. Further, it may be a wire grid polarizing plate capable of controlling the polarization in the ultraviolet region. It is preferable to use the dye-based polarizing plate described in WO 2005/015275 or the like, which has low absorption in the visible light region and high transmittance. A polarizing plate capable of producing polarized light in the ultraviolet light region, a polarized light emitting element used in the present invention, and a polarized light emitting plate, and a medium capable of controlling the polarization in the ultraviolet light region and dynamically controlling the phase difference, specifically By using a liquid crystal cell for the constitution, it is possible to obtain a light source or a display device of the present invention, which is capable of displaying by using polarized light in the ultraviolet region and has extremely high transparency.

  By providing a light source or a display device that emits polarized light in the visible light region so that vertically polarized light is incident when the light is irradiated to a medium that reflects light, It is possible to provide a display device capable of preventing an erroneous recognition, or a safety device for recognizing light or operation, which can prevent erroneous operation due to erroneous recognition.

  The light source or display device of the present invention can be suitably used particularly in a vehicle or a ship. For example, not only can a driver or a device that senses light be provided with light with little reflection, and a light source or a display device with high anti-glare property can be provided. This is preferable because a display device capable of preventing malfunction can be provided.

  Hereinafter, the present invention will be described in more detail with reference to Examples, but these are merely examples and do not limit the present invention in any way. Further, “%” and “part” described below are based on mass unless otherwise specified. In each structural formula of the compounds used in each of the examples and comparative examples, the acidic functional group such as a sulfo group is described in the form of a free acid.

(Polarizer)
The display of the present application was produced by using SKN-18243P (manufactured by Pola Techno Co., Ltd.) as a general polarizing plate. A general polarizing plate is a polarizing plate product having a high polarizing function in the visible region and a remarkably low light transmittance in the ultraviolet region.

(Synthesis example 1)
35.2 parts of commercially available 4-amino-4'-nitrostilbene-2,2'-disulfonic acid was added to 300 parts of water and stirred, and the pH was adjusted to 0.5 with 35% hydrochloric acid. To the obtained solution, 10.9 parts of 40% sodium nitrite aqueous solution was added, and the mixture was stirred at 10 ° C. for 1 hour, and subsequently 17.2 parts of 6-aminonaphthalene-2-sulfonic acid was added, followed by addition of 15% sodium carbonate aqueous solution. After the pH was adjusted to 4.0, the mixture was stirred for 4 hours. 60 parts of sodium chloride was added to the obtained reaction solution, the precipitated solid was separated by filtration, and further washed with 100 parts of acetone to obtain 124.0 parts of a wet cake of the compound of formula (6) as an intermediate. .

  62.3 parts of the obtained dry powder of the formula (6) was added to 300 parts of water and stirred, and the pH was adjusted to 10.0 using a 25% aqueous sodium hydroxide solution. 20 parts of 28% ammonia water and 9.0 parts of copper sulfate pentahydrate were added to the obtained solution, and the mixture was stirred at 90 ° C. for 2 hours. 25 parts of sodium chloride was added to the obtained reaction solution, the precipitated solid was separated by filtration, and further washed with 100 parts of acetone to obtain 40.0 parts of a wet cake of the compound of the formula (7). The wet cake was dried with a hot air drier at 80 ° C. to obtain 20.0 parts of a compound (λmax: 376 nm) of the following formula (7).

(Production of polarized light emitting element)
A polyvinyl alcohol film (VF-PS # 7500 manufactured by Kuraray Co., Ltd.) having a thickness of 75 μm was immersed in warm water of 40 ° C. for 3 minutes to swell the film. The film obtained by swelling was 1.0 part by weight of 4,4′-bis- (sulfostyryl) biphenyl disodium aqueous solution (Tinopal NFW Liquid manufactured by BASF) described in Compound Example 5-1. The obtained compound (7) was immersed for 4 minutes in an aqueous solution containing 0.3 part by weight of Glauber's salt, 1.0 part by weight of Glauber's salt, and 1,500 parts by weight of water, for 4 minutes. The obtained film was stretched 5 times in a 3% aqueous solution of boric acid at 50 ° C. for 5 minutes. The film obtained by stretching was washed with water at room temperature for 20 seconds while keeping the tension, and dried to obtain a polarized light emitting device.

(Production of polarized light emitting plate using polarized light emitting element)
A triacetyl cellulose film (ZRD-60 manufactured by Fuji Film Co., Ltd.) containing no ultraviolet absorber was treated in a 1.5 N aqueous sodium hydroxide solution at 35 ° C. for 10 minutes, washed with water, and then dried at 70 ° C. for 10 minutes. It was The triacetyl cellulose film obtained by the alkali treatment was laminated on both surfaces of the polarized light emitting element with an aqueous solution containing 4% polyvinyl alcohol resin (NH-26 manufactured by Nippon Vinegar Bipovar Co., Ltd.) and dried at 70 ° C. for 10 minutes. A polarized light emitting plate was obtained. When the polarized light emitting plate was irradiated with ultraviolet light, white light was emitted, and when the light emission was further confirmed through a polarizing plate, white polarized light was emitted in the stretching axis direction during processing of the polarized light emitting element, while It was confirmed that polarized light was not emitted on the non-stretched axis.

(Production of ultraviolet polarizing element)
A polyvinyl alcohol film (VF-PS # 7500 manufactured by Kuraray Co., Ltd.) having a thickness of 75 μm was immersed in warm water of 40 ° C. for 3 minutes to swell the film. The film obtained by swelling was treated with C.I. I. Direct Yellow 28 was dipped for 4 minutes in an aqueous solution containing 0.2 parts of Glauber's salt, 1.5 parts of Glauber's salt, and 1500 parts of water for 4 minutes. The obtained film was immersed in a 3% aqueous boric acid solution at 50 ° C. for 5 minutes and stretched 5 times. The stretched film was washed with water at room temperature for 20 seconds while keeping the tension, and dried to obtain an ultraviolet ray polarization element having the highest polarization degree at 408 nm and the polarization at 340 nm to 415 nm.

(Preparation of ultraviolet polarizing plate)
A triacetylcellulose film (ZRD-60 manufactured by Fuji Film Co., Ltd.) containing no ultraviolet absorber is treated with a 1.5 N aqueous sodium hydroxide solution at 35 ° C. for 10 minutes, washed with water, and then dried at 70 ° C. for 10 minutes. Let The triacetyl cellulose film obtained by the alkali treatment was laminated on both surfaces of the ultraviolet ray polarizing element with an aqueous solution containing 4% of polyvinyl alcohol resin (NH-26 manufactured by Nippon Acetate Bipovar Co., Ltd.), and the temperature was adjusted to 70 ° C. at 10 ° C. It was dried for a minute to obtain a polarizing plate. Hereinafter, this polarizing plate will be referred to as an ultraviolet region polarizing plate.

  The obtained polarizing plate, polarized light emitting plate, and ultraviolet polarizing plate were evaluated as follows.

[Evaluation]
(A) Single transmittance Ts, parallel transmittance Tp, and orthogonal transmittance Tc
The single-piece transmittance Ts, parallel-position transmittance Tp, and orthogonal-position transmittance Tc of each measurement sample were measured using a spectrophotometer (“U-4100” manufactured by Hitachi, Ltd.). Here, the single transmittance Ts is the transmittance of each wavelength when one measurement sample is measured. The parallel transmittance Tp is a spectral transmittance of each wavelength measured by overlapping two measurement samples so that their absorption axis directions are parallel to each other. The orthogonal transmittance Tc is a spectral transmittance measured by overlapping two polarizing plates so that their absorption axes are orthogonal to each other. The measurement was performed over a wavelength range of 220 to 780 nm.
(B) Polarization degree ρ
The polarization degree ρ of each measurement sample was obtained by substituting the parallel transmittance Tp and the orthogonal transmittance Tc into the following formula (I).
(Equation 1)
ρ = {(Tp-Tc) / (Tp + Tc)} ^1/2 × 100 ... Formula (I)
(C) Single transmittance Ys corrected for luminosity
The single-body transmittance Ys of each measurement sample is in the wavelength range of 400 to 700 nm in the visible range, and the single-body transmittance Ts obtained at every predetermined wavelength interval dλ (here, 5 nm) is the visual sensitivity according to JIS Z 8722: 2009. It is the corrected transmittance. Specifically, it was calculated by substituting the single transmittance Ts into the formula (I). In the formula (V) below, Pλ represents a spectral distribution of standard light (C light source), and yλ represents a 2-degree visual field color matching function.

(Equation 2)

  Each of the obtained polarized light emitting plate, ultraviolet polarizing plate, and polarizing plate has a single transmittance of 375 nm (Ts 375), a polarization degree of 375 nm (ρ 375), a transmittance corrected to visual sensitivity (Ys), and Table 1 shows the polarization degree (ρy) corrected to the sensitivity. The polarization function of each of the obtained ultraviolet light region and visible light region can be understood.

(D) Measurement of polarization of emitted light An ultraviolet LED 375 nm hand light type black light (“PW-UV943H-04” manufactured by Nichia Corporation) was used as a light inducing source, and the light inducing source was cut by UV transmission and visible light. A filter (“IUV-340” manufactured by Isuzu Seiko Glass Co., Ltd.) was installed to cut visible light. Then, a polarizing plate having a polarizing function in the visible light region and the ultraviolet light region (“SKN-18043P” manufactured by Polatechno Co., thickness 180 μm, Ys 43%) is arranged, and each measurement sample, that is, a polarized light emitting plate, Ultraviolet polarizing plate, polarizing plate is installed, and polarized light emission of the polarized light emitting plate, ultraviolet polarizing plate and polarizing plate is measured using a spectral irradiance meter (“USR-40” manufactured by Ushio Inc.). did. That is, the light from the light-inducing source includes an ultraviolet transmission / visible cut filter, a polarizing plate having a polarizing function in the visible light region and the ultraviolet light region, and each measurement sample (polarized light emitting plate, ultraviolet light polarizing plate, polarizing plate). , And was arranged in such a manner that polarized light was incident on the spectroradiometer and the measurement was performed. At that time, the spectral emission amount of each wavelength measured by superimposing so that the absorption axis of the measurement sample that maximizes the absorption of ultraviolet rays and the absorption axis direction of the ultraviolet / visible polarizing plate are parallel to each other is Lw (weak emission axis). , Superimpose so that the absorption axis of the measurement sample that maximizes the absorption of ultraviolet rays and the absorption axis direction of a polarizing plate (“SKN-18043P” manufactured by Polatechno Co., Ltd.) having a polarizing function in the visible light region and the ultraviolet light region are orthogonal to each other. Lw and Ls were measured by setting the spectral emission amount of each wavelength measured by Ls (strong emission axis). Each measurement sample, that is, a polarized light emitting plate, an ultraviolet polarizing plate, a polarizing plate, and a polarizing plate having a polarizing function in the visible light region and the ultraviolet light region has absorption axes parallel to each other, and a visible light region when the absorption axes are orthogonal to each other. By confirming the energy amount of the light emitted in the above, the emission amount of the polarized light in the visible light region of 400 nm to 700 nm was evaluated.

  Table 2 shows Ls and Lw of each obtained polarizing plate at each wavelength of 460 nm, 550 nm, 610 nm, and 670 nm.

As shown in Table 2, in the polarized light emitting plate, a high Ls value is detected, and it is shown that the difference between the Ls value and the Lw value is significant at the four measured wavelengths. It can be seen that light is emitted by irradiating with and the emitted light has a polarization function. Further, it can be seen that the difference between the Lw value and the Ls value is more remarkable at each of the wavelengths, and that there is a good contrast. Further, the chromaticity a ^* value and b ^* value at Ls of the polarized light emitting plate obtained from JIS Z 8781-4: 2013 were a ^* value of 0.68 and b ^* value of -1.2. . From this, it can be seen that the polarized light emitting plate emits white light. On the other hand, it can be seen that the ultraviolet polarizing plate and the polarizing plate did not emit light even when irradiated with light from the light-induced source.

[Example 1]
A white LED light is used as a light inducing source, and SKN-18243P (manufactured by Pola-Techno Co., Ltd.) as a general polarizing plate has an absorption axis in a horizontal direction with respect to a mirror-finished plastic (polycarbonate plastic plate) which is a reflection medium. The polarizing plate is arranged as described above to provide a light source of the present application that emits vertically polarized light (P-polarized light). When the light from the obtained light source is applied to the reflective medium, the visibility of the reflected light from the reflective medium is significantly reduced, and thus when the light from the light source is reflected from the reflective medium, it is significantly suppressed. I found out.

[Comparative Example 1]
A white LED light is used as a light inducing source, and SKN-18243P (manufactured by Pola-Techno Co., Ltd.) is used as a general polarizing plate having an absorption axis in a direction perpendicular to a mirror surface plastic (polycarbonate plastic plate) which is a reflection medium. The polarizing plate was arranged so that the horizontally polarized light (S polarized light) was emitted. When the obtained light was applied to the reflection medium, the light reflection was remarkably confirmed even though it passed through the polarizing plate.

[Example 2]
The polarized light emitting plate was arranged such that polarized light (P-polarized light) was emitted in a direction perpendicular to the mirror-shaped plastic (polycarbonate plastic plate), which is the reflection medium, of the light emission axis of the polarized light emitting plate, and was used as the light source of the present application. Ultraviolet light (ultraviolet LED 375 nm hand light type black light ("PW-UV943H-04" manufactured by Nichia Corporation)) as a light inducing source was irradiated to the polarized light emitting plate with ultraviolet light. . At that time, a visible light cut filter (IUV-340 manufactured by Isuzu Glass Co., Ltd.) was used to irradiate the light emitting portion of the black light so that the visible light was not emitted, and the polarized light emitting plate emitted polarized light. The obtained polarized light was applied to a mirror surface plastic, and the reflected light reflected from the plastic plate was confirmed. The visibility of the reflection of the light emitted from the light source of the present application was significantly reduced. From this, it was found that a light source that suppresses reflection can be produced even though it is a transparent film by installing a transparent polarized light emitting film so as to emit vertically polarized light. The direction of irradiating the polarized light emitting plate with the ultraviolet light from the light inducing source is not limited to the direction from which it is visually recognized, and it is sufficient if the polarized light emitting plate can be irradiated with the ultraviolet light. It has been found that a suppressing light source is obtained.

[Comparative Example 2]
The polarized light emitting axis of the polarized light emitting plate was arranged so that polarized light (S polarized light) in the horizontal direction could be emitted with respect to the mirror-finished plastic (polycarbonate plastic plate) that is a reflection medium. Ultraviolet light (ultraviolet LED 375 nm hand light type black light (“PW-UV943H-04” manufactured by Nichia Chemical Industry Co., Ltd.)) was used as a light inducing source to irradiate the polarized light emitting plate with ultraviolet light. At that time, a visible light cut filter (IUV-340 manufactured by Isuzu Glass Co., Ltd.) was used for the light emitting portion of the black light so that the visible light was not emitted, and light was emitted to emit polarized light. When the obtained polarized light was irradiated to a plastic which is a mirror surface and the reflected light reflected from the plastic plate was confirmed, the reflected light of the emitted light was sufficiently confirmed. From this, even if a film that emits polarized light is installed so as to emit polarized light in the horizontal direction, a light source that can suppress reflection cannot be obtained.

[Example 2A]
In Example 2, as a light emitting device of natural light having the same amount of light as the light source in which the polarization emission axis of the polarization light emitting plate was vertically polarized (P-polarized), the polycarbonate plastic (reflection medium) which is a mirror surface was irradiated with the LED light. In this case, when the incident angle of light is 0 ° in the direction perpendicular to the reflective medium and the reflected light amount is 1, the reflected light amount from the reflecting surface when the incident angle of light is changed with respect to the reflective medium is measured and displayed. The results shown in 3 were obtained. At that time, the amount of reflected light of the light emitting device (white LED light) of natural light and the amount of reflected light of the polarized light emitting axis of the polarizing light emitting plate in the vertical direction (P polarized light) are reflected on the polycarbonate plastic which is a mirror surface. The amounts of reflected light when light is incident are compared, and the results shown in Table 3 below are obtained. The amount of reflected light is a value obtained by using a luminance meter (CA-2000 manufactured by Konica Minolta Co., Ltd.) as a measurement value, and the amount of reflected light is the reverse position of the natural light (white LED) or the light source through the reflection medium. The meter was installed at the same angle as the light incident angle, and the amount of reflected light was measured.
The results are shown below.

  Regarding the reflectance of light polarized in the direction perpendicular to the reflection surface, the amount of reflection is 3.6 times smaller than that of natural light at an inclination angle of 40 °, and about 67 times less at an inclination angle of 70 °. It was found that the reflectance of light polarized in the direction perpendicular to the reflecting surface was 0.008 and the amount of reflected light was infinitely small. From this, it can be seen that when the light from the light source of the present application is emitted to the reflective medium, the reflection can be significantly suppressed.

[Example 2B]
In Example 2, the polarized light emitting plate was arranged so that the polarized light emitting axis of the polarized light emitting plate emits polarized light (S polarized light) in the direction parallel to the polycarbonate plastic (reflection medium) which is the mirror surface, and the polarized light emitting axis is 45 with respect to the polarized light emitting axis. A retardation plate made of a polycarbonate resin having a retardation value of 270 nm at a wavelength of 540 nm was attached so that the angle became °. The retardation plate having a retardation value of 270 nm is a film that functions as a 1 / 2λ retardation plate at a wavelength of 540 nm and has a transmittance of 92% or more at 380 nm to 780 nm. Using. The light emitted from the polarized light emitting plate is irradiated with ultraviolet light from a light inducing source (ultraviolet LED 375 nm hand light type black light ("PW-UV943H-04" manufactured by Nichia Corporation)) from a direction that can be reflected and visually recognized. went. At that time, a visible light cut filter (IUV-340 manufactured by Isuzu Glass Co., Ltd.) was used to irradiate the light emitting portion of the black light so that the visible light was not emitted, and the polarized light emitting plate emitted polarized light. The obtained polarized light was irradiated onto a polycarbonate plastic which is a mirror surface as a reflection medium from an angle of 60 ° when the vertical direction of the reflection medium was 0 °, and the reflected light reflected from the plastic plate was confirmed. . As a result, the visibility of the reflection of the light emitted from the light source was significantly reduced. Therefore, even if a polarized light emitting element or a polarized light emitting plate that emits polarized light that is transparent is installed so as to emit polarized light in a direction parallel to the reflective medium, a film having a retardation value of 1 / 2λ is used. As a result, it was found that the polarized light emitted from the polarized light emitting plate was changed from the polarized light in the parallel direction (S polarized light) to the polarized light in the vertical direction (P polarized light) with respect to the reflective medium, and a light source capable of suppressing the reflection could be manufactured. It has been found that the direction of irradiating the polarized light emitting plate with the ultraviolet ray, which is the light inducing source, is not limited to the direction in which it is visually recognized, but a light source that suppresses reflection can be obtained by irradiating the light in any direction.

[Example 2C]
In Example 2, the polarized light emitting axis of the polarized light emitting plate is arranged so that polarized light (P polarized light) in the vertical direction is emitted to the polycarbonate plastic plate (reflection medium) which is a mirror surface, and with respect to the polarized light emitting axis. A retardation plate made of a polycarbonate resin having a retardation value of 135 nm at a wavelength of 540 nm was laminated at 45 °. A retardation plate having a retardation value of 135 nm is a film functioning as a 1/4? Retardation plate at a wavelength of 540 nm and has a transmittance of 92% or more at 380 nm to 780 nm. Using. Light emitted from the light source of the present application, which is formed by laminating a retardation plate to the polarized light emitting plate, reflects the light emitted from the light source to emit ultraviolet light (ultraviolet LED 375 nm hand light type black light (Nichia) UV light irradiation was performed by "PW-UV943H-04" manufactured by Kogyo Co., Ltd.). At that time, the light emitting portion of the black light was irradiated with a visible light cut filter (IUV-340 manufactured by Isuzu Glass Co., Ltd. so that visible light was not emitted), and polarized light was emitted from the light source of the present application. The polarized light obtained from the light source is applied to a polycarbonate plastic, which is a mirror surface as a reflection medium, from an angle of 2 ° when the vertical direction of the reflection medium is 0 °, and the light reflected from the plastic plate is Using a polarizing plate in which a film having a retardation value of 135 nm with respect to the absorption axis was laminated at 45 °, from the polarizing plate side (position of the polarizing plate at an angle of ± 10 ° with respect to the vertical direction of the reflective medium). It was confirmed that the retardation plate was on the reflection medium side. As a result, it was found that the visibility of the reflected light from the light source was significantly reduced. From this, a film or the like having a retardation value of 1/4 λ, which is a transparent film and which is provided with a polarized light emitting element or a polarized light emitting plate that emits polarized light in a direction perpendicular to a reflection medium, is provided. It has been found that by using, it is possible to provide a light source capable of suppressing reflection when viewed through a polarizing plate. It has been found that the direction of irradiating the polarized light emitting plate with ultraviolet rays is not limited to the direction of visual recognition, and a light source that suppresses reflection can be obtained by irradiating light from any direction.

[Example 3]
The films were arranged so that the polarized light emission axes of the polarized light emitting plate were 90 ° in adjacent patterns, and a light source that emits polarized light having a pattern was produced. The polarized light emitting plate was irradiated with ultraviolet light from the direction of visual recognition using a light-induced source (ultraviolet LED 375 nm hand light type black light (“PW-UV943H-04” manufactured by Nichia Corporation)). At that time, a visible light cut filter (IUV-340 manufactured by Isuzu Glass Co., Ltd.) was used in the light emitting portion of the black light so that the visible light was not emitted. The light irradiated from the light source having the pattern was irradiated to the mirror surface plastic, and the reflected light reflected from the plastic plate was confirmed. In FIG. 1, in the pattern element of the polarized light emitting plate held by the finger, the position held by the finger is set as a position for emitting polarized light in the horizontal direction with respect to the reflection medium, and the position is set as a starting point, and the pattern is adjacent to each other by 90 °. The film is arranged so that At this time, any of the polarized light emitting plates forming the pattern has a pattern that emits polarized light whose polarization emission axes are different from each other in the horizontal direction and the vertical direction. It was On the other hand, when the reflected light of the polarized light obtained from it is confirmed, it can be seen that the reflected pattern and the pattern capable of suppressing the reflection are alternately provided. Furthermore, when the reflected light was confirmed, when the emission axis emitted vertically polarized light, reflection was suppressed and the light source functioned as a light source, but the emission axis emitted horizontally polarized light. In some cases, the reflection was not suppressed (Fig. 1). From this, it can be seen that the light source can provide light capable of suppressing reflection in a light source arranged perpendicular to the reflective medium. It has been found that the direction of irradiating the polarized light emitting plate with the ultraviolet light from the light inducing source is not limited to the visually recognizable direction, and a light source that suppresses reflection can be obtained by irradiating the light from any direction.

[Comparative Example 3]
In FIG. 1 in Example 3, the polarized light emission axis was set at an angle of 45 °, and reflected light was confirmed. As a result, the polarized light emitting plate has the same pattern as that of Example 3 (it emits polarized light so that the adjacent patterns have an angle of 90 °), but the polarized light obtained therefrom is reflected. Did not suppress the reflection as shown in FIG.

[Example 4]
In the structure of ultraviolet polarizing plate / liquid crystal cell / polarized light emitting plate, polarized light emitted from the polarized light emitting plate is emitted vertically to the polycarbonate plastic plate (reflection medium) which is the mirror surface. A transparent liquid crystal panel was prepared. The liquid crystal panel had a transmittance of 87% and had high transparency. In the liquid crystal panel, UV light is irradiated from the UV polarizing plate side with a light-inducing source (UV LED 375 nm hand light type black light (“PW-UV943H-04” manufactured by Nichia Corporation)). It was At that time, a visible light cut filter (IUV-340 manufactured by Isuzu Glass Co., Ltd.) was used in the light emitting portion of the black light so that the visible light was not emitted. Light emission from the obtained liquid crystal panel displayed characters and images according to the driving of the liquid crystal cell. When light emitted from the liquid crystal panel was applied to a plastic (reflective medium) as a mirror surface, and reflected light reflected from the plastic plate (reflective medium) was confirmed, light reflection was remarkably suppressed. From this, it was found that the display device of the present application capable of suppressing reflection that provides polarized light emission in the vertical direction with respect to the reflective medium could be manufactured.

[Comparative Example 4]
Same as Example 4 except that a transparent liquid crystal panel was produced so that the polarized light emitted from the polarized light emitting plate was emitted in the horizontal direction with respect to the polycarbonate plastic plate (reflection medium) which is the mirror surface. A display device was manufactured. When the light emitted from the obtained liquid crystal panel was applied to the plastic which is the mirror surface and the reflected light reflected from the plastic plate was confirmed, the reflection of the light was not suppressed and it was displayed on the reflective medium on the display device. I was able to fully confirm the characters and images displayed.

[Example 5]
In the front of each LED lamp that emits red, green, blue, and white, which is a light emitting device, the polarization emission axis of the polarization emission plate is perpendicular to the polycarbonate plastic plate (reflection medium) that is a mirror surface (P polarization). ) Is arranged so as to emit light, and the display device of the present application is manufactured. While illuminating each LED lamp that emits red, green, blue, and white light, the light source of ultraviolet light is emitted from the direction that is visually recognized by the polarized light emitting plate (ultraviolet LED 375 nm hand light type black light (manufactured by Nichia Corporation). "PW-UV943H-04")). At that time, the light emitting portion of the black light was irradiated with light using a visible light cut filter (IUV-340 manufactured by Isuzu Glass Co., Ltd.) so that visible light was not emitted. The polycarbonate resin, which is a mirror surface, was irradiated with the obtained light emission as a reflection medium from an angle of 60 ° when the vertical direction of the reflection medium was 0 °, and the reflected light reflected from the plastic plate was confirmed. As a result, the light of each LED lamp that emits red, green, blue, and white is sufficiently reflected by the reflective medium, while the visibility of the reflected light of the light emitted from the light source of the present invention with respect to the reflective medium. Fell significantly. From this, it was found that by using the light source of the present application for the reflective medium together with the LED lamp, it is possible to obtain a display device capable of emitting the reflected light and the light for which the reflection should be suppressed. This means that by using light from a light emitting device that does not have polarization and a light source that emits polarized light in a direction perpendicular to the reflection medium, the reflected light and the light whose reflection is to be suppressed are respectively It was found that the light source of the present invention capable of emitting light and a display device using the light source can be manufactured. From this, it can be understood that the high transparency of the polarized light emitting plate used in the light source of the present application does not reduce the amount of light reflected from the reflection medium of the light emitted from the light source having no polarization.

  From the above, when the light emitted from the light inducing source of the present application is converted into polarized light, or the light emitted from the light inducing source is used to emit polarized light, and when irradiating light to a medium that reflects light, , By providing a light source or an image display device capable of providing polarized light in the visible range so that vertically polarized light is incident on the reflective medium, it is possible to recognize human misrecognition and light and movement. It is possible to provide a display device that prevents malfunction due to misrecognition in the device. Further, a transparent polarized light emitting element or a polarized light emitting plate is installed so that polarized light is emitted in a direction perpendicular to a reflection medium, so that a light source or a display device which is transparent but can emit polarized light. It turns out that Such a light source or display device not only suppresses reflection when exposed to reflective plastics or stones (eg, marble), but it is also suitable for cars, bikes, bicycles and roads. By using it for a signage, a signboard, etc., it is possible to provide light whose reflection should be suppressed even in the presence of a puddle or snow in the environment. Similarly, a light source for ships or a display device can also provide light capable of suppressing reflection of light on the water surface.

  By using the light source or the display device of the present application, it is possible to provide light that can prevent malfunction due to erroneous recognition without taking measures to prevent malfunction in the conventional automatic safety device or image processing on the light receiving side of the camera. sell. Further, by using the light source or the display device of the present application, it is possible to provide light that suppresses light reflection, so that not only the malfunction due to the false recognition of the automatic safety device is eliminated, but also the visibility is improved for humans. It is possible to provide light capable of suppressing possible reflection. Further, as the light that does not reflect, it is possible to apply it by utilizing various advantages such as security and design.

Claims (8)

  When the light emitted from the light-induced source is converted into polarized light or the light emitted from the light-induced source is used to emit polarized light and the medium that reflects the light is irradiated with the light, it is perpendicular to the reflective medium. A light source or display device capable of providing polarized light in the visible range such that directional polarized light is incident.   The light source or display device according to claim 1, wherein the light transmittance is 40% or more and 100% or less.   The light source or display device according to claim 1 or 2, comprising a polarized light emitting element that emits polarized light in the visible range.   4. The light source according to claim 3, wherein the polarized light emitting element is a polarized light emitting element that emits light in the visible range by utilizing light in the ultraviolet range to the near-ultraviolet visible range emitted from the light inducing source. , Or display device.   An optical system comprising the light source or display device according to any one of claims 1 to 4 and a medium capable of reflecting light.   The light source according to any one of claims 1 to 4, a display device, or the optical system according to claim 5, which is used outdoors.   The light source according to any one of claims 1 to 4, a display device, or the optical system according to claim 5, which is used for a driving device.   The light source according to any one of claims 1 to 4, a display device, or the optical system according to claim 5, which is used for a vehicle such as an automobile, a motorcycle, a bicycle, or a ship.