JP6477026B2 - Video projection window - Google Patents

Description

  The present invention relates to a video projection window.

  Usually, the screen that displays the image light projected from the projector in a viewable manner is intended to display the image light projected from the projector regardless of whether it is a reflective type or a transmissive type. (Back side) cannot be observed. In the transmissive screen, the image light projected from the back side is transmitted to the observer side (front side) so that the image is displayed, so that the light from the back side can be transmitted. However, in such a transmissive screen, for example, because the surface has irregularities, it is possible to transmit light, but there is a case where the state on the back side cannot be observed.

  For example, there is a display device in which a screen is provided on a rear glass and an image is projected onto the screen according to a display device of a work machine (for example, Patent Document 1).

JP 2002-323869 A

  However, in the case of the display device disclosed in Patent Document 1, the amount of transmitted light and the direction of light vary greatly depending on the location, so the visibility on the other side is reduced and the background cannot be seen clearly.

  It is an object of the present invention to provide a video projection structure with high visibility of a projected video without reducing the visibility of a background image that can be seen through the video projection structure.

  According to one aspect of the present embodiment, a first transparent substrate that transmits light, a second transparent substrate that transmits light, the first transparent substrate, and the second transparent substrate. An image projection window sandwiched between the image projection films, the image projected from the image projection window among the images projected so as to be focused on the image projection film. Features.

  According to another aspect of the present embodiment, a first transparent substrate that transmits light, a second transparent substrate that transmits light, the first transparent substrate, and the second transparent substrate. A video projection window having a video projection film sandwiched between the transparent substrates of the video projection film, wherein the video projected through the video projection window is viewed from among the video images projected so as to be focused on the video projection film It is characterized by being able to.

  The video projection window used in the vehicle according to the present invention can increase the visibility of the projected video without reducing the visibility of the image seen through the video projection window.

Structure diagram of video projection window in the first embodiment Explanatory drawing of the image projection window in 1st Embodiment Process drawing (1) of the manufacturing method of the image projection window in 1st Embodiment Process drawing (2) of the manufacturing method of the image projection window in 1st Embodiment Modified example of video projection window in the first embodiment Explanatory drawing when the video projection window in 1st Embodiment is used for the vehicle Structure diagram of video projection window in second embodiment (1) Structural diagram of image projection window in second embodiment (2) Explanatory drawing of the image projection window in 2nd Embodiment Structural diagram of video projection window in the second embodiment (3) Process drawing (1) of the manufacturing method of the image projection window in 2nd Embodiment Process drawing (2) of the manufacturing method of the image projection window in 2nd Embodiment

  Modes for carrying out the invention will be described below. In addition, about the same member etc., the same code | symbol is attached | subjected and description is abbreviate | omitted.

  By the way, as an image projection window used in a vehicle, there is a method of attaching a film functioning as a screen to one surface of glass serving as a window. However, when a film is pasted on the outside of the window, the film is generally soft, so that it is likely to be exposed to wind and rain, or damaged by washing of the vehicle and the like, and a beautiful image is not easily obtained. In addition, when a film is attached to the inside of a window, for example, in the case of an automobile, the film surface is rubbed by opening and closing the window, and the film surface is damaged by wiping the window, and similarly, a beautiful image cannot be obtained. Cheap.

  Therefore, a highly durable video projection vehicle that can be used for a window of a vehicle or the like with high visibility of the video projected on the video projection window without reducing the visibility of the image seen through the video projection window. Windows are sought. That is, in the present application, the laminated glass structure can improve the durability of the image projection window as compared with the conventional one used by being attached to a vehicle window. In addition, as a laminated glass structure, an image projection vehicle window that can be used as a vehicle window with good visibility can be obtained by inserting an image projection film between the glasses.

[First Embodiment]
(Video projection window)
In the video projection window in this embodiment, the transmittance for visible light is preferably 1% or more, more preferably 5% or more, and further preferably 20% or more so that the outside scenery can be seen through. Further, in order to keep the gain as a screen appropriately, the visible light transmittance is preferably 90% or less, and more preferably 80% or less. In order to function as a screen, since a higher screen gain is better, the reflectance is preferably 5% or more, more preferably 25% or more, and further preferably 50% or more. Further, from the viewpoint of securing the transmittance, the reflectance is preferably 70% or less.

  The forward haze may be 15 or less and may be 10 or less. Further, the forward haze may be 0.2 or more, 0.5 or more, or 0.8 or more from the viewpoint of compatibility with the screen characteristics. The forward haze is a percentage of transmitted light that deviates by 2.5 ° or more from incident light.

  The rear haze may be 5 or more. Further, the rear haze may be 90 or less and 80 or less from the viewpoint of transparency. The back haze is a percentage of the reflected light that is deviated by 2.5 ° or more from the regular reflected light.

  The video projection structure is suitable for use in an environment where there is external light in the surroundings, and even if there is an environment of 100 lux or more within the range where the observer's line of sight to view the video projection structure can reach It is preferable that the projected image and the background can be seen. For this purpose, it is preferable that the rear haze is larger than the front haze.

  When light is incident on the surface of the image projection structure at an angle of 45 °, the light is scattered backward and in the normal direction of the image projection window with respect to the intensity of light scattered in the forward direction of the image projection window. The light intensity ratio (Ib / If) may be 0.8 or more, and is preferably larger than 1. It is important that external light that is incident on the image projection structure by oblique incidence is not visible to the viewer as much as possible. For this reason, it has been found that it is important for transparency that light on the side where the projection light is not incident on the image projection structure is difficult to be emitted to the observer. Therefore, it is necessary to maintain the above parameters appropriately. is there.

  In addition, as a parameter that achieves both transparency and gain as a screen, the light scattered in the normal direction of the image projection window when light is incident on the surface of the image projection structure at an angle of 45 ° is used. The ratio of the intensity of light scattered in the normal direction of the image projection window to the intensity (Ib / If) divided by the value of the forward haze is preferably 0.1 or more, and is 0.2 or more Preferably there is. The light source for measuring this parameter may be any light source that emits visible light. Specifically, the A light source, the B light source, the C light source, the D light source, D65, or their visible light range may be reproduced.

  In addition, as a parameter that achieves both transparency and a gain as a screen, “intensity of backscattered light at 45 ° incidence / 45 ° incidence when light is incident on the surface of the image projection structure at an angle of 45 °. The intensity of forward scattered light x backward haze / forward haze "is preferably 5 or more, and preferably 10 or more.

  If the image projection window satisfies the above optical conditions, it is possible to achieve both image visibility and background visibility even in an environment where ambient light exists. As external light, when there is direct sunlight, there is no direct sunlight, but when it is fine, it can be used even in an indoor environment of 100 lux or more.

  The video projection window in the first embodiment will be described with reference to FIG. The video projection window 100 in the present embodiment is a video projection vehicle window, and the video projection film is provided between the first transparent substrate 11 and the second transparent substrate 12 formed of glass or transparent resin. 20 is formed. The image projection film 20 is formed by laminating the first transparent layer 21, the reflective film 30, and the second transparent layer 22 from the first transparent substrate 11 side. A second transparent substrate 12 is formed.

  Concavities and convexities are formed on the surface of the first transparent layer 21, and a reflective film 30 is formed on the surface of the first transparent layer 21 where the concavities and convexities are formed. A second transparent layer 22 is formed on the reflective film 30 so as to embed irregularities.

  The first transparent layer 21 is preferably a transparent resin layer. The transparent resin is preferably a photo-curing resin such as an acrylic resin or an epoxy resin, a thermosetting resin, or a thermoplastic resin. In order to maintain transparency, the yellow index of the transparent resin is preferably 10 or less, and more preferably 5 or less so that the function as a window is not impaired. The transmittance of the first transparent layer 21 is preferably 50% or more, more preferably 75% or more, and further preferably 90% or more.

  The second transparent layer 22 is preferably a transparent resin layer. The transparent resin may be the same as that in the first transparent layer 21. The first transparent layer 21 may be made of the same material or may be made of a different material, but is preferably made of the same material. The second transparent layer 22 is preferably a transparent resin layer. The transmittance of the second transparent layer 22 is preferably 50% or more, more preferably 75% or more, and further preferably 90% or more.

  In the 1st transparent layer 21 and the 2nd transparent layer 22, thickness other than an uneven | corrugated | grooved part may be 0.5 micrometer or more and 50 micrometers or less.

  The reflective film 30 is formed of a metal film, a dielectric single layer, a multilayer film, or a combination thereof, and part of the light incident on the reflective film 30 is transmitted and the other part is reflected. Therefore, the reflective film 30 may be formed of any one of metal, metal oxide, and metal nitride. The reflective film 30 is preferably formed of a metal material containing aluminum (Al) or silver (Ag). The reflective film 30 is preferably made of a metal thin film or a film structure in which an oxide film, a metal thin film, and an oxide film are laminated in this order. The thickness of the metal thin film is preferably 1 nm to 100 nm or less, and more preferably 4 nm to 25 nm or less. Within this range, the function due to the roughness value Ra of the irregularities formed on the surface of the first transparent layer 21 can be utilized without hindering. The transmittance and reflectance of the image projection window in the present embodiment can be adjusted by changing the film thickness and type of the reflecting film 30.

The first transparent layer 21 and the second transparent layer 22 are preferably made of a material having a forward haze of 20 or less when the same material is processed into a flat plate having an average thickness, and more preferably 15 or less. preferable. Further, the absorption in the visible light range is exp when the extinction coefficients k ₁ and k _{2 of} the first transparent layer 21 and the second transparent layer 22 are A and the visible light wavelength λ is Ra. It is preferable that (−2πA × | k ₁ −k ₂ | / λ)> 0.25. The shape of the transparent resin and the unevenness may be a random unevenness, a lens array, a lens array having a plurality of shapes of lenses, a blazed hologram, a pseudo-blazed hologram, or the like. In particular, random unevenness is preferable because a film mold can be used, and the area can be easily increased.

  In the image projection window 100 according to the present embodiment, it is preferable that the difference in refractive index between adjacent layers is within 0.2 because the reflectance at the interface between the layers is suppressed to within 0.5%. Moreover, since the reflectance in each layer interface will be about 0.1% as it is less than 0.1, it is more preferable.

  The difference in refractive index between the first transparent layer 21 and the second transparent layer 22 is such that the wavelength of light in the visible range is λ with respect to the roughness value Ra of the unevenness formed on the surface of the first transparent layer 21. When the absolute value of the difference in refractive index is Δn, the value of Δn × Ra / λ is preferably within 1. Further, in consideration of interface reflection, transmitted scattered light, and the degree of freedom of the concavo-convex structure, the difference in refractive index between the first transparent layer 21 and the second transparent layer 22 is preferably within 0.1. Is more preferably within 0.05, and even more preferably within 0.02. Moreover, when the 1st transparent layer 21 and the 2nd transparent layer 22 are formed with the organic resin, ratio of the volume ratio of the double bond and the triple bond contained in resin of each layer is 50%-150%. A range is preferable. Further, the first transparent layer 21 and the second transparent layer 22 preferably have a material density ratio in the range of 80% to 120%.

  As the glass constituting the first transparent substrate 11 and the second transparent substrate 12, soda lime glass is preferable. In order to improve durability, chemical strengthening, hard coating, or the like may be performed. As the transparent resin constituting the first transparent substrate 11 and the second transparent substrate 12, polycarbonate, PET film, PEN film, cycloolefin polymer film, polyester film and the like are preferable. In particular, it is preferable that the substrate has no birefringence.

  If the first transparent substrate 11 and the second transparent substrate 12 are transparent resins such as a PET film, a PEN film, and a cycloolefin film, the video projection window 100 in the present embodiment is used as a window glass for an automobile. When used, it is preferable because of its good adhesion to the interlayer film for laminated glass.

  The image projection window 100 in the present embodiment is a reflection type image projection window, and projects an image from the projector 110 onto the image projection window 100 and is reflected by the image projection window 100 as shown in FIG. This is for viewing by the observer on the side where the projector 110 is installed.

  In the image projection window 100 in the present embodiment, it is preferable that the transmitted color shows a bluish color because a transparent feeling is given. In the chromaticity diagram, when white light is transmitted, it is more preferable that x <0.33.

(Method for manufacturing image projection window)
Next, the manufacturing method of the video projection window in this Embodiment is demonstrated based on FIG.3 and FIG.4.

  First, as shown in FIG. 3 (a), a mold 90 having an uneven surface 90a formed on the surface is prepared. The mold 90 may be a resin film having irregularities formed on the surface, or may be a white or black film with a matte surface, a glossy surface, or a release film. It may be a mold in which irregularities are formed. Regarding the surface characteristics, it is preferable that the change in glossiness within the same plane is small, and when the ratio of glossiness at two different locations within the same plane is taken, it may be within 50% to 200%. preferable. It is preferable that the film having unevenness on the surface is not subjected to easy adhesion treatment. Mold or film with irregularities formed on the surface, for example, the surface of the material with irregularities formed by cutting, dry etching, wet etching, sand blasting, surface molding by extrusion molding, molding mixed members such as fine particles Concavities and convexities may be formed by using a surface structure generated when the film is formed or by applying a self-organizing material. The mold material may be Ni-based material, stainless steel, Cu-based material, quartz, glass or the like. Moreover, a mold release treatment may be performed on the formed uneven surface.

  On the other hand, the entire surface of the unevenness of the surface of the mold 90 may be partially or partially partially uneven. In the case of such a surface, the ratio of the glossiness at two different places in the same plane may not be within the above range. A highly anisotropic shape can be created by stretching a film with irregularities, sandblasting the film in an oblique direction, or the like.

  Next, as shown in FIG. 3B, a first transparent substrate 11 such as a glass substrate is prepared, and a resin material for forming the first transparent layer 21 on the first transparent substrate 11. The UV curable resin (ultraviolet curable resin) is applied by die coating, spin coating, inkjet coating, spray coating, or the like. Thereafter, the mold 90 is placed on the UV curable resin applied on the first transparent substrate 11. The mold 90 is placed so that the surface of the mold 90 on which the unevenness 90a is formed is on the UV curable resin. Thereafter, the UV curable resin is cured by irradiating the UV curable resin with 200 to 10,000 mJ of UV light (ultraviolet light), thereby forming the first transparent layer 21. In addition, when forming the 1st transparent layer 21 with a thermosetting resin, after mounting the shaping | molding die 90 on a thermosetting resin, a thermosetting resin is hardened by heating. When the first transparent layer 21 is formed of a thermoplastic resin, the thermoplastic resin is heated to place the mold 90 and then cooled to solidify the thermoplastic resin.

  Next, as shown in FIG. 3C, the mold 90 is peeled off from the first transparent layer 21. Thereby, the surface of the unevenness 21a formed on the surface of the first transparent layer 21 is exposed.

  Next, as shown in FIG. 4A, a reflective film 30 is formed on the surface of the first transparent layer 21 where the irregularities 21a are formed. The reflective film 30 is formed by depositing an Al film on the surface on which the irregularities 21a are formed by vacuum deposition or sputtering.

  The reflective film 30 is preferably formed to have a thickness of 1 nm to 100 nm or less, more preferably 4 nm to 25 nm. The reflective film 30 is formed so as to have a reflectance of preferably 5% or more, more preferably 15% or more, and further preferably 30% or more. Moreover, it is preferable that the reflectance of the reflective film 30 does not change abruptly depending on the color. When the wavelength of typical light for each of RGB is 630 nm, 530 nm, and 465 nm, it is preferable that the ratio of Log (common logarithm) values of the respective reflectances is in the range of 0.5 to 2.

  Next, as shown in FIG. 4B, the second transparent layer 22 is formed on the reflective film 30. Specifically, a UV curable resin (ultraviolet curable resin) for forming the second transparent layer 22 is formed on the reflective film 30 formed on the unevenness 21a in the first transparent layer 21. Apply by die coating. Thereafter, the UV curable resin is cured by irradiating the UV curable resin with UV light (ultraviolet light) to form the second transparent layer 22. Note that the second transparent layer 22 may be formed of a thermosetting resin or a thermoplastic resin. As a result, the image projection film 20 including the first transparent layer 21, the reflective film 30, and the second transparent layer 22 is formed on the first transparent substrate 11.

  The video projection film 20 may have the following configuration. It may be a half mirror laminated with a scattering material. It may be reflected, deflected, or diffused by a volume hologram. It may be deflected, reflected, or diffused by a kinoform hologram or other irregular surface or a structure in which a reflective film is formed on the surface. A cholesteric liquid crystal or a polymer cholesteric liquid crystal may be used. The cholesteric liquid crystal may be aligned and formed on the uneven surface. The surface of the polymer cholesteric liquid crystal may be roughened by etching or the like. A cholesteric liquid crystal in which a liquid crystal layer is formed using a substrate having horizontal alignment and vertical alignment may be used. A cholesteric liquid crystal to which a surfactant is added may be applied on a substrate and the application surface may be vertically distributed, or the orientation of the application surface may be reduced. .

  Next, as shown in FIG. 4C, the second transparent substrate 12 is pasted on the image projection film 20 with an adhesive layer (not shown).

  About the 1st transparent substrate 11 and the 2nd transparent substrate 12, it is 0.05 mm-less than 10 mm as a range with which durability as a base material is maintained, Preferably, it is less than 0.1 mm-5 mm.

  Moreover, when a transparent resin film is used for the first transparent substrate 11, the thickness is preferably such that a roll process can be applied, 0.01 mm to 0.5 mm, more preferably 0.05 mm to 0.3 mm. More preferably, it is within 0.15 mm.

  In addition, when this image projection window is used for an automobile, the image projection film 20 has a thickness of 0.05 mm to 0.3 mm, and even if a film is partially introduced between the window glasses, foam biting is suppressed. It's easy to do.

  Moreover, the thickness of the first transparent layer 21 and the second transparent layer 22 other than the concavo-convex portions may be 0.5 μm or more, and is preferably 50 μm or less considering that it is created by a roll process. Further, it is preferable that the surface roughness Ra is 2 times or less of the unevenness Ra because the thickness is sufficient to suppress shrinkage and the like during molding while reducing the amount of resin and reducing the cost.

(Modification)
Next, a modified example of the video projection window in the present embodiment will be described.

  A modification of the image projection window in the present embodiment is an image projection window having a structure made of laminated glass, as shown in FIG. Specifically, in the video projection film 20 formed by the first transparent layer 21, the reflective film 30, and the second transparent layer 22, the first transparent layer 21 side is provided with the first transparent layer by the adhesive layer 51. The resin film 41 and the first glass substrate 61 are bonded to each other, and the second transparent resin film 42 and the second glass substrate 62 are bonded to the second transparent layer 22 side by the adhesive layer 52. Are bonded together. In addition, the 2nd glass substrate 62 may be adhere | attached on the 2nd transparent layer 22 with the contact bonding layer 52, without providing the 2nd transparent resin film 42. FIG. In this modification, the adhesive layers 51 and 52 are made of, for example, EVA (Ethylene-vinyl acetate) resin or PVB (Poly vinyl butyral) resin, acrylic adhesive, other adhesives, UV curable resin, or the like. .

  The adhesive layers 51 and 52 are for bonding the first glass substrate 61 to the first transparent resin film 41 and the second glass substrate 62 to the second transparent resin film 42, for example, And a thermoplastic resin composition containing a thermoplastic resin as a main component. Although the thickness of the adhesive layers 51 and 52 is not necessarily limited, for example, 0.01 to 1.5 mm is preferable, and 0.05 to 0.5 mm is more preferable.

  Examples of the thermoplastic resin used for the adhesive layers 51 and 52 include thermoplastic resins conventionally used for this type of application. For example, plasticized polyvinyl acetal resin, plasticized polyvinyl chloride resin, saturated polyester resin, plasticized saturated polyester resin, polyurethane resin, plasticized polyurethane resin, ethylene-vinyl acetate copolymer resin, ethylene- Examples include ethyl acrylate copolymer resins.

  The adhesive layers 51 and 52 preferably contain a UV absorbing material. The deterioration of the resin portion can be suppressed by including the UV absorbing material.

(Application of image projection window)
Next, the use of the video projection window in the present embodiment will be described.

  For video applications, the video projection window can be mounted on side windows, rear windows, and windshields. In particular, it is preferable to mount the video projection window on the outer periphery of the windshield because both high forward visibility and information display can be achieved.

  The laminated glass structure is good because it has sufficient durability against wind and rain, heat, and sunlight. In addition, when this video projection window is used, the visibility is sufficient and the window can be used as a window. Moreover, when it gets dirty, the surface can be cleaned by a method equivalent to a normal glass material, and can be easily cleaned by car washing or the like.

  In addition, by mounting on the side window, it is possible to display and provide surrounding information to the passenger, and to display images such as movies and sports.

  In addition, by mounting on the rear window, it is possible to assist recognition of an object that is difficult to see with an arrow or the like when there is an object behind when confirming the rear. Further, by displaying the part that becomes the blind spot behind, it is possible to safely proceed backward. At that time, since the focus of the projected image can be adjusted to the image projection unit, it is difficult to be affected by distortion due to the laminated shape or surface shape of the glass, and a clear image can be provided to the observer.

  Since the projection image from the projector can be focused on the image projection film, the image projection film is not easily affected by distortion due to the laminated shape of the glass near the focal position or the surface shape. In order to obtain a clearer image, the thickness unevenness of the transparent member on the projector side is preferably within 50%, preferably within 25%, and more preferably within 10%. In addition, this video projection window is mounted on the outer periphery of the windshield, and it is not always necessary to the driver by presenting arbitrary information, but when the driver needs it, he / she can visually recognize the necessary information. Can be used.

  Furthermore, when the first transparent layer 21 formed by a mold having anisotropic unevenness is provided, it is easier to display so as to be visible only to the driver or the passenger seat. As another method, the arithmetic average roughness of the projections and depressions is set to 0.3 μm or less so that strong reflected light is generated only in the direction close to the regular reflection of the projector so that the image is displayed only on the driver and the passenger seat. The position of the projector may be adjusted so that it can be seen. In addition, when the first transparent layer 21 having a concavo-convex shape and a controlled viewing angle is provided, a projection window having a high gain and a high transmittance and a wide viewing angle in a specific direction such as a horizontal direction or a vertical direction are provided. This is preferable for automobiles.

  Moreover, if the transparent substrate on the indoor side of the side window or rear window is colored glass, it can be used as a privacy window.

  Conversely, when the transparent substrate on the back side of the side window or rear window is colored glass, it can be used as a window that exhibits the function of the screen from the inside while expressing the clearness of the glass in appearance.

  Further, when the image projection window is applied to a windshield of an automobile, the haze value is preferably 4 or less, more preferably 2 or less, still more preferably 1 or less, and particularly preferably 0.8 or less. When the haze value is small, the visibility becomes good and the double image is suppressed. In this case, the first transparent substrate 11 and the second transparent substrate 12 may be made of a transparent resin film such as a PET film, a triacetyl cellulose film, or a cycloolefin film.

  Further, when the image projection window is applied to a windshield of an automobile, a double image can be suppressed by applying a low reflection film on the surface. The low reflection film may be on either surface, but is preferably applied on the incident side (observer side).

It can also be used by introducing it to the following parts.
・ Information display on the shade part of the windshield ・ Information display on the lower part of the windshield for automobiles ・ Information on the taxi and limousine in the car partition, advertisement in the video display bus (on the back of the driver)
-In car sun visors, minivans, SUVs, TV and DVD images are displayed as in-car partitions. ] Is displayed.
・ Display more detailed information around the meter. ・ Screen for door glass. ・ Connect to GPS, Internet, and external cameras, etc., when the weather is bad, such as rainy weather, snowfall, etc. Information and position information are displayed on the windshield.
・ Window glass on the back of the driver's seat (prevents reflection of interior lighting when driving underground)
・ Information display on railway side window glass ・ Suspended in advertisement ・ Partition part of Shinkansen ・ Glass function for window glass for linear motor car ・ Window for train In particular, when used after sunset, a decrease in contrast due to the influence of external light can be suppressed. For example, the video projection window in the first embodiment can be used as a window of a vehicle 300 such as a train as shown in FIG.

[Second Embodiment]
(Video projection window)
The video projector in the present invention is a video projection structure having a visible light transmittance of 5% or more and 90% or less, a front haze of 4 or more and 40 or less, and a rear haze of 0 or more and 60 or less. The intensity of the backscattered light when the light is incident at an angle of 45 ° with respect to the surface of the image projection window is lower than the intensity of the forward scattered light.

  The transmittance in visible light may be 20% or more, and may be 40% or more. Within this range, the visibility of the outside scenery is good. Moreover, in order to keep the gain as a screen suitable, the transmittance | permeability in visible light may be 80% or less. In order to function as a screen, the higher the screen gain, the better. Therefore, the reflectance may be 15% or less, or 10% or less. Moreover, it may be 1% or more, and may be 5% or more.

  The forward haze may be 5 or more, and may be 8 or more. It may be 20 or less. The forward haze is a percentage of transmitted light that deviates by 2.5 ° or more from incident light.

  The rear haze may be 5 or more. The rear haze may be 40 or less or 20 or less from the viewpoint of transparency. The back haze is a percentage of the reflected light that is deviated by 2.5 ° or more from the regular reflected light.

  The intensity of light scattered backward and in the normal direction of the video projection window when light is incident on the surface of the video projection structure from an angle of 45 ° is scattered forward and in the normal direction of the video projection window. Less than light intensity.

  Further, in terms of transparency with respect to visual recognition of the background, the reflectance (r), the rear haze (Hb), and the front when light is incident at an angle of 45 ° with respect to the surface of the video projection structure. And the ratio (r / If) of the ratio (Ib / If) of the intensity (Ib) of light scattered back and in the normal direction of the image projection window to the intensity (If) of light scattered in the normal direction of the image projection window × Hb × Ib / If) is preferably 500 or less, preferably 250 or less, and more preferably 100 or less.

  Further, in the visibility of the image, the forward logarithm of the transmittance (log T), the forward haze (Hf), and the front when the light is incident at an angle of 45 ° with respect to the surface of the image projection structure, The product (logT ×) of the ratio (Ib / If) of the intensity (Ib) of light scattered back and in the normal direction of the image projection window to the intensity (If) of light scattered in the normal direction of the image projection window Hf × Ib / If) is preferably 10 or more.

Further, in the balance between the visibility of the image and the visibility of the background, when the light loss is 100−transmittance (%) − reflectance (%), the square of the transmittance (T ² ) and the light loss (loss) ) And the image projection window behind and against the intensity (If) of light scattered forward and in the normal direction of the image projection window when light is incident on the surface of the image projection structure at an angle of 45 °. The product (T ² × loss × Ib / If) of the ratio (Ib / If) of the intensity (Ib) of the light scattered in the normal direction is preferably 100,000 or more. This is because the balance between gain and transmittance is good. When it is 200,000 or more, the effect of further improving the contrast becomes stronger.

  Next, a video projection window according to the second embodiment will be described with reference to FIG. The video projection window 200 in the present embodiment is a video projection vehicle window, and a video projection film 210 is formed between the first transparent substrate 211 and the second transparent substrate 212. The image projection film 210 is formed on the second transparent substrate 212 so as to cover the plurality of striped light scattering portions 220 extending in the one-dimensional direction, and the second transparent substrate 212 and the light scattering portion 220. And the formed transparent resin layer 230. The light scattering portion 220 is formed so that its cross section has a triangular shape, a trapezoidal shape, a bell shape, or the like. In the present embodiment, a structure in which a plurality of light scattering portions 220 extending in a one-dimensional direction is formed in a stripe shape as described above may be referred to as a louver structure. In the present embodiment, a plurality of light scattering portions 220 are linearly formed inside the transparent resin layer 230, and the plurality of light scattering portions 220 are arranged at a predetermined interval.

  In the present embodiment, the first transparent substrate 211 is formed of glass or a resin film that transmits light. For the transparent resin layer 230, a photo-curing resin such as an acrylic resin or an epoxy resin, a thermosetting resin, a thermoplastic resin, or the like can be used, and a yellow index is used to maintain transparency so that the function as a window is not impaired. Is preferably 10 or less, and is preferably 5 or less.

  The light scattering portion 220 is formed of a transparent resin containing a light scattering material or a transparent resin containing a light scattering material and a light absorbing material. As the transparent resin used for the light scattering portion 220, a photo-curing resin such as an acrylic resin or an epoxy resin, a thermosetting resin, a thermoplastic resin, or the like can be used. The light scattering material includes fine particles of high refractive index materials such as titanium oxide (refractive index: 2.5 to 2.7), zirconium oxide (refractive index: 2.4), aluminum oxide (refractive index: 1.76), and the like. , Fine particles of low refractive index materials such as porous silica (refractive index: 1.25 or lower), hollow silica (refractive index: 1.25 or lower), resin materials having different refractive indexes that are not compatible with the transparent resin, and crystallization A resin material having a thickness of 1 μm or less can be used. The concentration of the light scattering material contained in the light scattering portion 220 is preferably 0.01 vol% or more and 5 vol% or less, and more preferably 0.05 vol% or more and 1 vol% or less.

  Further, as the light absorbing material, carbon black, titanium black, or the like can be used. The concentration of the light absorbing material contained in the light scattering portion 220 is preferably 0.01 vol% or more and 5 vol% or less, and more preferably 0.1 vol% or more and 3 vol% or less. It should be noted that by including a light absorbing material in the light scattering portion 220, part of the light propagating in the image projection window as unnecessary stray light can be absorbed, and the scattered light is reduced. It is possible to suppress the phenomenon of appearing cloudy and improve the transparency. Further, by reducing the concentration of the light scattering material or the light absorbing material, it is easy to make the material uniform, and the characteristics of the light scattering portion 220 can be made uniform easily.

  In the image projection window in the present embodiment, it is preferable that the refractive index of the first transparent substrate 211 and the second transparent substrate 212 is equal to the refractive index of the transparent resin layer 230. The difference between the refractive index of the first transparent substrate 211 and the second transparent substrate 212 and the refractive index of the transparent resin layer 230 and the refractive index of the light scattering portion 220 is preferably 0.01 or less, and 0.005 or less. Is more preferable, and 0.001 or less is still more preferable. This is because if the difference between the refractive index of the transparent resin layer 230 and the refractive index of the light scattering portion 220 is large, multiple images that are seen through the image projection window appear. In addition, the light scattering material and the light absorbing material often have a refractive index much larger or smaller than that of the organic resin, and the change in the refractive index is suppressed by reducing the concentration thereof. The material used is equivalent to the material used for the transparent resin layer 230, or the refractive index can be included in the above range by slight composition adjustment.

  The thickness of the first transparent substrate 211 and the second transparent substrate 212 is 0.05 mm to 0.3 mm between the window glass when the video projection window in the present embodiment is used for an automobile. Even if a film is partially introduced, it is easy to suppress foam biting.

  As shown in FIG. 8, the image projection window in the present embodiment has a light scattering fine particle 221 inside a transparent resin layer 230 formed between the first transparent substrate 211 and the first transparent substrate 211. May be dispersed. The light scattering fine particles 221 may be fine particles of a high refractive index material such as titanium oxide, zirconium oxide, or aluminum oxide described above, or fine particles of a low refractive index material such as porous silica or hollow silica. The light scattering fine particles 221 preferably have an average particle size of the light scattering fine particles 221 of 50 nm or more and 1000 nm or less, and more preferably 100 nm or more and 1000 nm or less. The light scattering fine particles are a kind of light scattering material.

  The image projection film 210 may have the following configuration. It may be transmitted, deflected, or diffused by a volume hologram. It may be deflected, scattered, or diffused by a kinoform hologram or other configuration having an uneven surface.

  Further, since the purpose of the video projection window is to be able to visually recognize the background, it is assumed that external light exists in the vicinity. In this case, external light is propagated and scattered by being incident on the image projection window, thereby causing a phenomenon in which the contrast of the image and background projected from the image projection window is reduced. Therefore, by forming the transparent resin with a light scattering material and a light absorbing material, it is possible to suppress the phenomenon that the external light is emitted from an unnecessary part and the contrast of the image and the background is lowered, and good visibility is achieved. Can be maintained. The amount of absorption is preferably 0.5% or more, preferably 5% or more, and more preferably 10% or more with respect to vertically incident light. Further, if the absorption is 90% or less, the amount of the projected image light can be appropriately used, and is preferably 75% or less, and more preferably 50% or less.

  Note that the video projection window 200 in the present embodiment is a transmissive video projection window. That is, as shown in FIG. 9, an image is projected from the projector 110 onto the image projection window 200, and an image that is seen through the image projection window 200 is on the side opposite to the side where the projector 110 is installed. It is for the observer to see.

(Method for manufacturing image projection window)
Next, a method for manufacturing a video projection window having the structure shown in FIG. 10 will be described as a method for manufacturing a video projection window in the present embodiment.

  The image projection window having the structure shown in FIG. 10 is made of laminated glass, and the first transparent substrate 211 is pasted by the adhesive layer 251, and the second transparent substrate 212 is pasted by the adhesive layer 252. It is of the structure that has been.

  A method of manufacturing the video projection window in the present embodiment shown in FIG. 10 will be described with reference to FIGS.

  First, as shown in FIG. 11A, a transparent resin layer 230 is formed on the first transparent resin film 241. Specifically, a photocurable resin is applied to the surface of the first transparent resin film 241 by spin coating, and a molding die 290 is pressed onto the photocurable resin applied by spin coating to irradiate ultraviolet rays. By doing so, the photocurable resin is cured to form the transparent resin layer 230. Thereafter, the mold 290 is peeled off from the transparent resin layer 230. Thereby, the transparent resin layer 230 having the groove 230a having a shape corresponding to the shape of the light scattering portion 220 is formed on the surface. The mold 290 is formed of a mold resin and is provided with a protrusion 290a having a shape corresponding to the shape of the light scattering portion 220. The mold 290 is pressed so that the surface on which the protrusions 290 a are provided is on the photocurable resin applied by spin coating, and the grooves 230 a corresponding to the shape of the protrusions 290 a are formed on the transparent resin layer 230. To be formed on the surface. As a result, a groove 230 a for forming the light scattering portion 220 having a louver structure can be formed on the surface of the transparent resin layer 230.

  Next, as illustrated in FIG. 11B, the light scattering portion 220 is formed in the groove 230 a of the transparent resin layer 230. Specifically, a paste containing an ultraviolet curable resin for forming the light scattering portion 220 is supplied to the groove 230a of the transparent resin layer 230, and the excess is scraped off with a doctor blade. Thereby, the paste is embedded in the groove 230 a of the transparent resin layer 230. Thereafter, the light scattering portion 220 is formed in the groove 230a of the transparent resin layer 230 by irradiating ultraviolet rays and curing the paste. In this manner, the light scattering portion 220 having a louver structure is formed. The light scattering part 220 formed in this way may be called a light scattering louver.

  The paste for forming the light scattering portion 220 is formed by mixing titanium oxide fine particles as a light diffusing material in a desired concentration with the ultraviolet curable resin used when forming the transparent resin layer 230. Yes.

  Next, as illustrated in FIG. 11C, a photocurable resin that forms the second transparent resin film 242 is applied on the transparent resin layer 230 and the light scattering portion 220 to be the image projection film 210. As a result, the surface can be flattened when unevenness occurs when the light scattering portion 220 is formed. Specifically, an ultraviolet curable resin (not shown) used for forming the transparent resin layer 230 is applied on the transparent resin layer 230 and the light scattering portion 220, and then the applied photocurable resin is coated. A transparent substrate (not shown) is placed on the substrate, irradiated with ultraviolet rays, and then the transparent substrate is peeled off. Thereby, the second transparent resin film 242 is formed on the transparent resin layer 230 and the light scattering portion 220.

  Next, as shown in FIG. 12, the image projection window is laminated into glass. Specifically, two soda lime glasses to be the first transparent substrate 211 and the second transparent substrate 212 and PVB films to be the adhesive layers 251 and 252 are prepared. Thereafter, a PVB film to be an adhesive layer 251 and a first transparent substrate 211 are sequentially laminated on the first transparent resin film 241, and a PVB to be an adhesive layer 252 is formed on the second transparent resin film 242. A film and a second transparent substrate 212 are sequentially laminated. Thereafter, the image projection window shown in FIG. 10 which becomes a laminated glass having a light scattering louver can be produced by vacuum thermocompression bonding.

  The adhesive layers 251 and 252 are for adhering the first transparent substrate 211 and the second transparent substrate 212, and are made of, for example, a thermoplastic resin composition mainly composed of a thermoplastic resin. is there. Although the thickness of the adhesive layers 251 and 252 is not necessarily limited, for example, 0.025 to 1.0 mm is preferable, and 0.05 to 0.2 mm is more preferable.

  As an application for automobiles, the image projection window can be mounted on a side window, a rear window, or a windshield as in the first embodiment. In particular, mounting on the outer periphery of the windshield is preferable because both high forward visibility and information display can be achieved. By using this video projection window, it can be used to call attention and signage to the surroundings.

  In addition, by mounting on the side window, when the side door is opened, the door glass will be alerted. ] Can be displayed, and information can be provided to observers around the vehicle to alert the surroundings.

  Also, by mounting on the rear window, it is possible to alert the surroundings when traveling backward. At that time, the projected image can be focused on the image projection unit, so you can see the image at the same time as you actually see the vehicle, and there is no need to review the focal length for the image. Information can be recognized.

  Although it is not easily affected by distortion due to the laminated shape of the glass or the surface shape, the thickness unevenness of the transparent member on both the projector side and the image emitting side should be within 50%, and within 25% Preferably, it is more preferably within 10%.

  In addition, this video projection window is mounted on the outer peripheral portion of the windshield, and by presenting arbitrary information, taxi or buses can display the operation status, and the convenience of the user can be improved.

  Moreover, if the transparent substrate on the indoor side of the side window or rear window is colored glass, it can be used as a privacy window.

  Further, when the image projection window is applied to a windshield of an automobile, the haze value is preferably 4 or less, more preferably 2 or less, still more preferably 1 or less, and particularly preferably 0.8 or less. When the haze value is small, the visibility becomes good and the double image is suppressed. In this case, the first transparent substrate 11 and the second transparent substrate 12 may be made of a transparent resin film such as a PET film, a triacetyl cellulose film, or a cycloolefin film.

  Further, when the image projection window is applied to a windshield of an automobile, a double image can be suppressed by applying a low reflection film on the surface. The low reflection film may be on either surface, but is preferably applied to the transmission side (observer side).

In automobiles, etc.
・ Display of information to the outside on the shade part of the windshield ・ Installed on the rear glass, backlight ・ HMSL, information display on the back, bus destination display ・ Information display on the lower part of the car windshield ・ Taxi Information on limousine in-car partition, advertisement in video bus (inside of driver)
・ Information display on the car sun visor ・ In minivans and SUVs, TV and DVD images are displayed as in-car partitions ・ When the door on the side is opened, a warning is displayed on the door glass. ] Is displayed.
・ Around the meter ・ Door glass screen ・ Connect to GPS, the Internet, etc., display information such as advertisements for surrounding facilities ・ Indication of warnings such as stopping to the left and right vehicles, turning, etc.
・ Information display on railway side window glass ・ Suspended in advertisement ・ Partition part of Shinkansen ・ Glass function for window glass for linear motor car ・ Window for train Especially after sunset. For example, the video projection window in the first embodiment can be used as a window of a vehicle 300 such as a train as shown in FIG.

  The contents other than the above are the same as those in the first embodiment.

Example 1
First, as the mold 90, a sandblast film having random irregularities formed on the surface was used. The roughness value (Ra) of random irregularities formed on the surface of the mold 90 was about 1.2 μm.

  Next, as shown in FIG. 3B, a PET film having a thickness of 0.1 mm is prepared, and a UV curable resin (ultraviolet curable) for forming the first transparent layer 21 on the PET film is prepared. Resin) OGSOL EA-F5003 was applied by die coating. Thereafter, the mold 90 was placed on the UV curable resin applied on the PET film. The mold 90 was placed so that the surface of the mold 90 on which the random irregularities 90a are formed is on the UV curable resin. Thereafter, the UV curable resin was cured by irradiating the UV curable resin with 1000 mJ of UV light (ultraviolet light) to form the first transparent layer 21.

  Next, as shown in FIG. 3 (c), the mold 90 was peeled off from the first transparent layer 21. Thereby, the surface of the random unevenness | corrugation 21a currently formed in the surface of the 1st transparent layer 21 was exposed.

  Next, as shown to Fig.4 (a), in the 1st transparent layer 21, the reflecting film 30 was formed in the surface in which the random unevenness | corrugation 21a was formed. The reflective film 30 was formed by depositing an Al film with a thickness of 12 nm on the surface on which the random irregularities 21a were formed by vacuum deposition.

  Next, as shown in FIG. 4B, Oxol EA-F5003, which is a UV curable resin (ultraviolet curable resin) for forming the second transparent layer 22, is formed on the reflective film 30 by die coating. Applied. Thereafter, the UV curable resin was cured by irradiating the UV curable resin with 1000 mJ of UV light (ultraviolet light) to form the second transparent layer 22. As a result, the image projection film 20 is formed on the first transparent substrate 11 by the first transparent layer 21, the reflective film 30, and the second transparent layer 22.

  Next, as shown in FIG. 4C, the second transparent substrate 12 is pasted on the image projection film 20 with an adhesive layer (not shown).

  The manufactured image projection window has a transmittance of 25% at d-line and a reflectance of 35%.

(Example 2)
As the transparent resin film, a transparent polyethylene terephthalate (PET) film (refractive index: 1.58) having a thickness of 50 μm was prepared. The refractive index is a value measured at room temperature using d-line (wavelength 589 nm) of a sodium lamp. As an ultraviolet curable resin, Hitaroid 7981 (manufactured by Hitachi Chemical Co., Ltd., specific gravity 1.1) was prepared. An ultraviolet curable resin was applied to the surface of the transparent resin film by spin coating.

  A mold 290 having a plurality of protrusions arranged in a stripe on a flat surface was prepared. A molding die 290 was pressed onto the applied ultraviolet curable resin at a temperature of 25 ° C. and a gauge pressure of 0.5 MPa. The transparent resin layer 230 was formed by curing the photocurable resin by irradiating ultraviolet rays. Thereafter, the mold 290 was peeled off from the transparent resin layer 230.

  As a result, a groove having a groove pitch of 80 μm, a groove width of 40 μm, a groove depth of 80 μm, a groove length of 100 mm, and a triangular cross section is formed on the surface of the transparent resin layer 230 in an area of 800 mm × 300 mm. Been formed. Thereby, the groove | channel for forming the light-scattering part 220 used as a louver structure was able to be formed.

  As a paste for forming the light scattering portion 220, fine particles of titanium oxide (average particle size 0.2 μm, specific gravity 4.2) are used as the light scattering material in the ultraviolet curable resin used when forming the transparent resin layer 230. What was mixed so that it might become 0.2 vol% was prepared. The paste was supplied to the groove of the transparent resin layer 230, and the excess was scraped off with a doctor blade. Then, the light-scattering part 220 was formed in the groove | channel of the transparent resin layer 230 by irradiating an ultraviolet-ray and hardening a paste.

  Next, after applying the ultraviolet curable resin used when forming the transparent resin layer on the transparent resin layer 230 and the light scattering portion 220, the transparent substrate is placed on the ultraviolet curable resin, After irradiating with ultraviolet rays, the transparent substrate is peeled off. Thus, an image projection structure in which the second transparent resin film 242 was formed on the transparent resin layer 230 and the light scattering portion 220 was produced.

  Next, as shown in FIG. 12, the image projection window was laminated into glass. Specifically, two soda lime glasses (3 mm thickness) to be the first transparent substrate 211 and the second transparent substrate 212 and PVB films (250 μm thickness) to be the adhesive layers 251 and 252 were prepared. Thereafter, a PVB film to be an adhesive layer 251 and a first transparent substrate 211 are sequentially laminated on the first transparent resin film 241, and a PVB to be an adhesive layer 252 is formed on the second transparent resin film 242. A film and a second transparent substrate 212 were laminated in order. Then, the image projection window shown in FIG. 10 which becomes a laminated glass having a light scattering louver therein was manufactured by vacuum thermocompression bonding.

  The manufactured image projection window had a transmittance of 75%, a haze of 15%, and 85% of the light transmitted through the image projection window without being diffracted. Further, the diffracted light having the highest intensity diffracted in the image projection window is first-order diffracted light, and the diffraction efficiency of this first-order diffracted light is 5%.

(Example 3)
In Example 3, the image projection window produced in Example 1 can be used as a rear side window that is an image projection vehicle window of an automobile or the like. By using the image projection window prepared in Example 1 as the rear side window of an automobile or the like, it is possible to see the scenery outside the automobile and also to see the image projected on the rear side window with high visibility. Can do.

  As mentioned above, although the form which concerns on implementation of this invention was demonstrated, the said content does not limit the content of invention.

11 First transparent substrate 12 Second transparent substrate 20 Image projection film 21 First transparent layer 21a Random irregularities 22 Second transparent layer 30 Reflective film 41 First transparent resin film 42 Second transparent resin film 51 Adhesive layer 52 Adhesive layer 90 Mold 90a Random unevenness 100 Video projection window 110 Projector 200 Video projection window 210 Video projection film 211 First transparent substrate 212 Second transparent substrate 220 Light scattering portion 230 Transparent resin layer 230a Groove 241 First transparent resin film 242 Second transparent resin film 251 Adhesive layer 252 Adhesive layer 261 First glass substrate 262 Second glass substrate 290 Mold 290a Protrusion 300 Vehicle

Claims (5)

A first transparent substrate that transmits light;
A second transparent substrate that transmits light;
An image projection film sandwiched between the first transparent substrate and the second transparent substrate;
A video projection window comprising:
The video projection film has a first transparent resin layer, a reflective film, and a second transparent resin layer in the order close to the first transparent substrate,
The first transparent resin layer has irregularities on a surface far from the first transparent substrate, the reflective film is configured in a thickness range of 1 nm to 100 nm, and the second transparent resin layer is Constructed to fill the unevenness,
Among the images projected so as to be focused on the image projection film, the image reflected in the image projection window can be seen ,
A video projection window having a reflectance of 25% or more .   The image projection window according to claim 1, wherein the unevenness of the surface of the first transparent resin layer is random unevenness. 3. The image projection window according to claim 1, wherein the visible light transmittance is 1% or more and 90% or less, and the reflectance is 70 % or less. It said first transparent substrate and the second transparent substrate are both glass substrates or, both formed by polycarbonate, image projection window according to any one of claims 1 to 3. The image projection window, image projection window according to claim 1, any one of 4, characterized in that the video projection vehicle window used in a vehicle.

Images