WO2013021756A1

WO2013021756A1 - Screen and image display device

Info

Publication number: WO2013021756A1
Application number: PCT/JP2012/067099
Authority: WO
Inventors: 孝史石川
Original assignee: 日本電気株式会社
Priority date: 2011-08-08
Filing date: 2012-07-04
Publication date: 2013-02-14
Also published as: JPWO2013021756A1; JP5928467B2

Abstract

This screen has a substrate, a screen layer laminated on the substrate, and a prism sheet disposed on the screen layer. The screen layer has a plurality of phosphor layers and black stripes disposed between each of the phosphor layers included in the plurality of phosphor layers that are adjacent to each other. The prism sheet has a prism surface on the side thereof opposite from the substrate. The prism surface has a plurality of prism rows and channel parts disposed in positions corresponding to the black stripes. The channel parts have a structure such that the width of the channel part becomes smaller toward the bottom part of the channel part.

Description

Screen and image display device

The present invention relates to a screen and an image display device.

As an image display device that displays an image according to an image signal, there is a rear projector that displays an image by irradiating light from the rear side of the screen.

In Patent Document 1 (Japanese Translation of PCT International Publication No. 2009-537868), a beam between a plurality of phosphor layers that are excited by beam light and output visible light of different colors and adjacent phosphor layers are provided on a substrate. A rear projector is disclosed that displays an image by scanning a light beam output from a light source provided on the rear side of a screen on a screen in which a screen layer formed with a divider that blocks light is laminated. Yes. Patent Document 1 discloses a prism sheet in which prisms are arranged in a certain direction on one surface of a sheet, and the prism surface on which the prisms are formed faces the opposite side of the substrate. Techniques for placement are disclosed.

The light output from the phosphor layer is isotropically diffused, and about half is output to the rear side of the screen. Therefore, the light extraction efficiency to the front side of the screen is deteriorated. Therefore, as disclosed in Patent Document 1, the light output from the phosphor layer to the rear side of the screen is arranged by arranging the prism sheet so that the prism surface faces the light source side arranged on the side opposite to the substrate. Is reflected to the front side of the screen by the prism, so that the light extraction efficiency can be increased.

JP 2009-537868 A

When a prism sheet is provided as disclosed in Patent Document 1, the beam light applied to the prism sheet is divided by the prism and is incident on the screen layer. It becomes larger than the beam diameter at the time of irradiation (see FIG. 13A of Patent Document 1).

FIG. 1 is a cross-sectional view showing a schematic configuration of a screen 20 having the above-described screen layer and prism sheet.

The screen layer 21 is laminated on the substrate 4.

The screen layer 21 includes a plurality of phosphor layers that output visible light of different colors, for example, a phosphor layer 211R that outputs red visible light, a phosphor layer 211G that outputs green visible light, and a blue layer A phosphor layer 211B that outputs visible light and a divider 212 that shields the beam light output from the light source are formed between adjacent phosphor layers.

The prism sheet 22 is disposed on the screen layer 21 such that the prism surface faces the opposite side of the screen layer 21.

In FIG. 1, it is assumed that beam light is irradiated from the vertical direction to the screen 20 at a position on the prism sheet 22 corresponding to the divider 212. As described above, the light beam applied to the prism sheet 22 is divided by the prism. Therefore, as shown in FIG. 1, the beam diameter D 2 when entering the screen layer 21 is larger than the beam diameter D 1 when irradiating the prism sheet 22. As shown in FIG. 2, when the screen 20 is irradiated with light beams from an oblique direction, the beam diameter D2 further increases.

When the beam diameter D2 at the time of incidence on the screen layer 21 is increased, as shown in FIGS. 1 and 2, the beam light is simultaneously incident on the adjacent phosphor layers, for example, the phosphor layer 211R and the phosphor layer 211G. So-called crosstalk may occur. When crosstalk occurs, there is a problem that visible light of different colors is simultaneously output from the respective phosphor layers, and the color purity of the display image is lowered.

It should be noted that Patent Document 1 describes that the expansion of the beam diameter can be suppressed by thinning the prism sheet. However, for example, a thin prism sheet having a thickness of 50 μm or less is difficult to manufacture, is easily broken, and is difficult to handle.

An object of the present invention is to provide a screen and an image display device capable of suppressing a decrease in color purity of a display image.

In order to achieve the above object, the screen of the present invention comprises:
A substrate,
A screen layer laminated on the substrate;
A prism sheet disposed on the screen layer,
The screen layer has a plurality of phosphor layers and a black stripe disposed between adjacent ones of the phosphor layers included in the plurality of phosphor layers,
The prism sheet has a prism surface on the side opposite to the substrate,
The prism surface has a plurality of prism rows and a groove portion disposed at a position corresponding to the black stripe,
The groove has a structure in which the width of the groove decreases toward the bottom of the groove.

In order to achieve the above object, an image display device of the present invention provides:
The above screen;
A light source provided on the rear side of the screen for outputting beam light;
An optical scanning unit that scans the beam light output from the light source and irradiates the screen.

According to the present invention, it is possible to suppress a decrease in color purity of a display image.

It is a figure which shows the state by which the light beam was irradiated to the related screen from the perpendicular direction. It is a figure which shows the state by which the beam light was irradiated to the related screen from the diagonal direction. It is a figure which shows the structure of the image display apparatus of one Embodiment of this invention. It is sectional drawing of the screen shown in FIG. It is a figure which shows the irradiation state of the beam light to the related screen. It is a figure which shows the irradiation state of the beam light to the screen shown in FIG. It is a figure which shows the specific structural example of the screen shown in FIG. It is a figure which shows the state by which the beam light was irradiated to the screen shown in FIG. 4 from the orthogonal | vertical direction. It is a figure which shows the state by which the beam light was irradiated to the screen shown in FIG. 4 from the diagonal direction. It is a figure for demonstrating the inclination | tilt angle of the slope of the groove part shown in FIG. FIG. 5 is a diagram illustrating a state in which light output from the phosphor layer causes retroreflection on the screen illustrated in FIG. 4. It is a figure which shows the relationship between the inclination-angle of the slope of a groove part shown in FIG. 4, and a retroreflectance. It is a figure which shows an example of the manufacturing method of the screen shown in FIG. It is a figure which shows another example of the manufacturing method of the screen shown in FIG. It is a figure which shows another example of the manufacturing method of the screen shown in FIG. It is a figure which shows an example of the shape of the slope of the groove part shown in FIG. It is a figure which shows another example of the shape of the slope of the groove part shown in FIG. It is a figure which shows an example of the shape of the bottom part of the groove part shown in FIG. It is a figure which shows another example of the shape of the bottom part of the groove part shown in FIG.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

FIG. 3 is a diagram showing a configuration of the image display apparatus 1 according to the embodiment of the present invention.

The image display apparatus 1 shown in FIG. 3 includes a light source 2, an optical scanning unit 3, and a screen 10.

The light source 2 is provided on the rear side of the screen 10 and outputs beam light.

The light scanning unit 3 scans the beam light output from the light source 2 according to the image signal and irradiates the screen 10.

The screen 10 has a screen layer 11 and a prism sheet 12.

The screen layer 11 is formed with a plurality of phosphor layers that are excited by the beam light output from the light source 2 and output visible light of different colors in a stripe shape.

The prism sheet 12 is arranged on the light source 2 side of the screen layer 11 so that the prism surface on which the prism is formed faces the light source 2 side. The surface of the prism surface is covered with a low refractive material having a refractive index lower than that of the prism member or air.

In the image display device 1 shown in FIG. 3, the laser beam output from the light source 2 is scanned by the light scanning unit 3 and enters the screen layer 11 through the prism sheet 12. When the beam light is incident, visible light is output from the phosphor layer of the screen layer 11 and an image is displayed. Here, as described above, about half of the light output from the phosphor layer is output to the rear side of the screen 10. However, the light output to the rear side of the screen 10 is reflected to the front side of the screen 10 by the prism of the prism sheet 12. Therefore, the light extraction efficiency to the front side of the screen 10 can be increased.

Next, the configuration of the screen 10 of this embodiment will be described.

FIG. 4 is a cross-sectional view of the screen 10 of the present embodiment in a direction orthogonal to the extending direction of the phosphor layer.

In FIG. 3, a screen layer 11 is laminated on a substrate 4 (not shown).

The screen layer 11 is excited by the beam light output from the light source 2, and outputs a phosphor layer 111R that outputs red visible light, a phosphor layer 111G that outputs green visible light, and blue visible light. The phosphor layers 111B to be formed are formed in a stripe shape in this order. Hereinafter, when the phosphor layers 111R, 111G, and 111B are not distinguished, they are referred to as the phosphor layer 111. The screen layer 11 is formed with a black stripe 112 that shields the beam light between the adjacent phosphor layers 111. The black stripe 112 corresponds to the divider 212 shown in FIG.

The color of visible light output from the phosphor layer 111, the number of phosphor layers 111 that output different colors of visible light, and the like can be changed as appropriate depending on the application of the screen 10. Further, for example, a blue light beam may be used, and instead of the phosphor layer 111B, a diffusion layer that diffuses the light beam and outputs diffused light may be formed. FIG. 4 shows an example in which a low refractive index layer 113 made of air or a low refractive material is formed between the phosphor layer 111 and the prism sheet 12. 113 is not necessarily essential.

A prism sheet 12 is disposed on the screen layer 11.

The prism sheet 12 has a prism row 121 in which prisms having a width larger than the wavelength of the light beam and a width in a direction perpendicular to the extending direction of the phosphor layer 111 are smaller than the width of the phosphor layer 111 are formed in a row. A plurality are formed. Examples of the prism member include PET (polyethylene terephthalate), PC (polycarbonate), PMMA (polymethyl methacrylate), and COP (cycloolefin polymer).

The plurality of prism rows 121 are formed substantially parallel to each other along the extending direction of the phosphor layer 111. The prism sheet 12 is arranged such that the prism surface on which the prism row 121 is formed faces the opposite side of the substrate 4.

Further, in the prism sheet 12, a groove 122 is formed at a position on the prism surface corresponding to the black stripe 112 of the screen layer 11 along the extending direction of the phosphor layer 111. The cross-sectional shape in the direction perpendicular to the extending direction of the phosphor layer 111 of the groove 122 is a trapezoid whose short side faces the substrate 4 side and whose long side faces the opposite side of the substrate 4 as shown in FIG. The width of the groove 122 decreases toward the bottom of the groove 122.

In FIG. 4, the screen layer 11 and the prism sheet 12 are in contact with each other. However, the present invention is not limited to this example. For example, an air layer is provided between the screen layer 11 and the prism sheet 12. May be present.

Next, the difference in the case where the light beam is irradiated on the screen 10 of the present embodiment and the screen 20 shown in FIG. 1 will be described.

FIG. 5 is a diagram showing the irradiation state of the beam light onto the screen layer 21 of the screen 20.

As shown in FIG. 5, it is assumed that the light beam tilted by a predetermined angle toward the phosphor layer 211R is irradiated at a position on the prism sheet 22 corresponding to the vicinity of the boundary between the phosphor layer 211G and the divider 212. The light beam is split by the prism of the prism sheet 22, and the beam diameter when entering the screen layer 21 is larger than the beam diameter when irradiating the prism sheet 22 in the direction orthogonal to the extending direction of the phosphor layer 211. growing. As a result, crosstalk in which the beam light is simultaneously incident on the adjacent phosphor layers 211R and 211G occurs, and visible light is simultaneously output from each phosphor layer, so that the color purity of the display image is lowered. In order to prevent a decrease in color purity of the display image, it is conceivable to turn off the laser light output around the position on the prism sheet 22 where the irradiation position of the laser light corresponds to the divider 212. However, when the output of the laser beam is turned off, the brightness of the display image decreases.

FIG. 6 is a diagram showing the irradiation state of the beam light onto the screen layer 11 of the screen 10. In FIG. 6, similarly to FIG. 5, the beam light tilted by a predetermined angle toward the phosphor layer 111 R at a position on the prism sheet 12 corresponding to the vicinity of the boundary between the phosphor layer 111 G and the black stripe 112. Is irradiated.

As described above, in the prism sheet 12, the width in the direction orthogonal to the extending direction of the phosphor layer 111 decreases toward the bottom at the position corresponding to the black stripe 112 (the extending direction of the phosphor layer 111). The groove 122 is formed in such a manner that the width in the direction orthogonal to the width increases toward the opposite side of the substrate 4. Therefore, as shown in FIG. 6, the light beam is applied to the slope of the groove 122 on the phosphor 111 G side and the bottom of the groove 122.

The beam light applied to the inclined surface of the groove 122 on the phosphor layer 111G side is refracted toward the phosphor layer 111G, and the beam light applied to the bottom of the groove 122 is refracted toward the black stripe 112 side. As a result, compared to the screen 20, the expansion of the beam diameter at the time of incidence on the screen layer 11 is suppressed, and beam light does not enter the adjacent phosphor layers 111R and 111G at the same time, so that crosstalk occurs. Therefore, it is possible to suppress a decrease in color purity of the display image.

An example of a specific configuration (dimension) of the screen 10 is shown in FIG.

The width of the phosphor layer 111 is 0.48 mm, and the width of the black stripe 112 is 0.12 mm. In addition, the width of one subpixel composed of the phosphor 111 and the black stripe 112 is 0.60 mm.

The thickness of the prism sheet 12 is 0.20 mm. The width of the prism portion, which is an area where the prism row 121 is formed, sandwiched between two adjacent groove portions 122 is 0.336 mm. The bottom of the groove 122 is substantially parallel to the screen layer 11 and the distance between the bottom of the groove 122 and the screen layer 11 is 0.08 mm. The width of the bottom of the groove 122 is the same as the width of the black stripe 112. The width of the bottom of the groove 122 is not necessarily the same as the width of the black stripe 112, and the width of the bottom of the groove 122 may be larger than the width of the black stripe 112. However, if the width of the bottom of the groove 122 is increased, the width of the prism is reduced and the effect of improving the light extraction efficiency is reduced. Therefore, the width of the bottom of the groove 122 and the width of the black stripe 112 are the same. Is preferred. The slope thickness of the groove 122 (depth of the groove 122) is 0.12 mm. The inclination angle of the slope of the groove 122 with respect to the bottom of the groove 122 is 59 degrees, and the width of the slope of the groove 122 is 0.072 mm.

When the simulation is performed on the screen 10 shown in FIG. 7 assuming that the light beam is irradiated under the same conditions as in FIG. 6, the incident amount of the light beam irradiated on the prism sheet 12 to the phosphor layer 111G is 57%. The amount of incident light on the phosphor layer 111R was 0%.

On the other hand, when the simulation is performed on the screen 20 assuming that the prism sheet 22 has a sheet thickness of 0.2 mm and the light beam is irradiated under the same conditions as in FIG. Was 75%, and the amount of incident light on the phosphor layer 211R was 11%. From the above simulation results, it can be seen that the provision of the groove 122 in the prism sheet 12 can prevent the simultaneous incidence of the beam light to the adjacent phosphor layers 111.

In addition, in the screen 10 of this embodiment, even if the irradiation position and irradiation angle of a laser beam change, it can prevent a laser beam from entering into the adjacent fluorescent substance layer 111 simultaneously.

FIG. 8 is a diagram showing a state in which beam light is irradiated from the vertical direction on the screen 10 of the present embodiment. In FIG. 8, the state A shows a state where the beam light is irradiated to the position on the prism sheet 12 corresponding to the phosphor layer 111G, and the state B is near the slope of the groove 122 on the phosphor layer 111G side. The state in which the light beam is irradiated is shown, and the state C shows a state in which the light beam is irradiated in the vicinity of the slope of the groove 122 on the phosphor layer 111R side.

In state A, the beam light is split by the prism and the beam diameter is increased, but all the beam light is incident on the phosphor layer 111G.

In the state B, the beam light applied to the slope of the groove 122 on the phosphor layer 111G side is refracted toward the phosphor layer 111G, enters the phosphor layer 111G, and is applied to the bottom of the groove 122. Refracts toward the black stripe 112 and enters the black stripe 112.

In the state C, the beam light applied to the slope of the groove 122 on the phosphor layer 111R side is refracted toward the phosphor layer 111R, enters the phosphor layer 111R, and is applied to the bottom of the groove 122. Refracts toward the black stripe 112 and enters the black stripe 112.

Therefore, in any of the states A to C, the beam light is not incident on the adjacent phosphor layers 111 at the same time.

FIG. 9 is a diagram showing a state in which the light beam in a state inclined by 30 degrees in the right direction is incident on the screen 10 of the present embodiment. In FIG. 9, states A to C are the same as states A to C in FIG.

Therefore, in any of the states A to C, the beam light is not incident on the adjacent phosphor layers 111 at the same time. Thus, in the screen 10 of this embodiment, even if the irradiation position and the irradiation angle of the laser beam are changed, it is possible to prevent the laser beam from being simultaneously incident on the adjacent phosphor layers 111.

In the case where the low refractive index layer 113 is formed, the laser beam irradiated to the inclined surface of the groove 122 and refracted toward the phosphor layer 111 side to the boundary surface between the prism sheet 12 and the low refractive index layer 113. When the incident angle exceeds the total reflection angle, the light is reflected to the light source 2 side. The condition for the beam light refracted on the inclined surface of the groove 122 not to be totally reflected at the boundary surface between the prism sheet 12 and the low refractive index layer 113 is expressed by Expression (1).

In Expression (1), θ ₁ is an inclination angle of the light beam irradiated on the inclined surface of the groove portion 122 from a direction orthogonal to the screen layer 11, θ ₂ is an inclination angle of the inclined surface of the groove portion 122 with respect to the screen layer 11, θ ₃ is an inclination angle of the light beam refracted on the slope of the groove 122 from a direction orthogonal to the screen layer 11, n ₁ is a refractive index of the surface of the prism sheet 12, n ₂ is a refractive index of the prism sheet 12, and n ₃ Is the refractive index of the low refractive index layer 113 (see FIG. 10).

From Equation (1), the maximum value of the inclination angle θ ₂ of the inclined surface of the groove 122 is determined by the inclination angle θ _{1 of the} light beam, that is, the maximum scanning angle of the light beam in the direction orthogonal to the direction in which the groove 122 is formed. You can see that Therefore, for example, in the formula (1), when θ ₁ = 30 degrees, n ₁ = n ₃ = 1.0, and n ₂ = 1.5, in order for the beam light to enter the phosphor layer 111, the groove portion inclination angle theta ₂ of the inclined surface 122 is required to be 60 degrees or less.

As shown in FIG. 11, the light output from the phosphor layer 111 to the light source 2 side and totally reflected by the slope of the groove 122 is reflected by the prism in accordance with the inclination angle θ ₂ of the slope of the groove 122. Thus, the rate of returning to the front side of the screen 10 (retroreflectance) changes.

FIG. 12 is a diagram showing the relationship between the slope angle θ ₂ of the slope of the groove 122 and the retroreflectance. 12, the horizontal axis shows the inclination angle theta ₂ of the inclined surface of the groove 122, and the vertical axis represents the retroreflectivity. In FIG. 12, the apex angle of the prism is 90 degrees, the refractive index of the prism material is 1.51, and the region in contact with the surface of the prism sheet 12 is an air layer (refractive index 1.0).

As shown in FIG. 12, the retroreflective ratio is best when the inclination angle theta ₂ of the inclined surface of the groove 122 is 70 degrees, it is possible to increase the light extraction efficiency.

As described above, in the case where the low refractive index layer 113 is formed, the maximum value of the inclination angle θ ₂ of the inclined surface of the groove 122 for allowing the beam light to enter the phosphor layer 111 is the maximum scanning angle of the beam light. Determined by. Therefore, within the scope of the inclination angle theta ₂ of the inclined surface of the groove 122 is determined by the maximum scan angle of the light beam, by an inclined angle theta ₂ as retroreflectivity is the highest, the beam to the phosphor layer 111 The light extraction efficiency can be increased while light is incident.

Next, a method for manufacturing the screen 10 of this embodiment will be described.

FIG. 13 is a diagram illustrating an example of a method for manufacturing the screen 10 of the present embodiment.

In step 1, the screen layer 11 is laminated on the substrate 4. Specifically, the phosphor layer 111 and the black stripe 112 are formed on the substrate 4, and the low refractive index layer 113 is formed on the phosphor layer 111. The method for manufacturing the screen layer 11 is well known to those skilled in the art and is not directly related to the present invention, and thus detailed description thereof is omitted.

In step 2, the prism sheet material 120 is laminated on the screen layer 11.

In step 3, the prism row 121 is formed on the surface of the prism sheet material 120 by the imprint method using the mold 31 corresponding to the shape of the prism row 121.

In step 4, the groove 122 is formed at a position corresponding to the black stripe 112 of the screen layer 11 using the dicer 32 corresponding to the shape of the groove 122. As a result, the prism sheet 12 in which the groove 122 is formed at a position corresponding to the prism row 121 and the black stripe 112 is laminated on the screen layer 11.

FIG. 14 is a diagram showing another example of the method for manufacturing the screen 10 of the present embodiment.

Step 1 and Step 2 are the same as those in FIG.

In step 3, a prism 33 corresponding to the shape of the prism row 121 and corresponding to the shape of the groove 122 at a position corresponding to the black stripe 112 is applied to the surface of the prism sheet material 120 by the imprint method. The row 121 and the groove 122 are formed in a lump. As a result, the prism sheet 12 in which the groove 122 is formed at a position corresponding to the prism row 121 and the black stripe 112 is laminated on the screen layer 11.

FIG. 15 is a diagram showing still another example of the method for manufacturing the screen 10 of the present embodiment.

Step 1 and Step 2 are the same as those in FIG.

In step 3, using the mold 34 corresponding to the shape of the groove 122, the groove 122 is formed at a position corresponding to the black stripe 112 on the surface of the prism sheet material 120 by the imprint method.

In step 4, the prism row 121 is formed by imprinting using a mold 31 corresponding to the shape of the prism row 121 in a region other than the region in which the groove 122 is formed in step 3 on the surface of the prism sheet material 120. Is formed. As a result, the prism sheet 12 having the groove 122 formed at the position corresponding to the prism row 121 and the black stripe 112 of the screen layer 11 is laminated on the screen layer 11.

In addition, in this embodiment, although the case where the inclined surface of the groove part 122 was a plane was demonstrated as an example, it is not restricted to this. For example, the slope of the groove 122 is a curved surface that is convex toward the opposite side of the substrate 4 as shown in FIG. 16A, or a polygon that is convex toward the opposite side of the substrate 4 as shown in FIG. It may be a shape. Note that the optimum shape of the inclined surface of the groove 122 is determined by conditions on the light source 2 side (such as the incident angle of the beam light).

In the present embodiment, the case where the bottom of the groove 122 is a plane has been described as an example, but the present invention is not limited to this. For example, as shown in FIG. 17A, the bottom of the groove 122 is a curved surface that is convex toward the side opposite to the substrate 4 (light source 2 side), or toward the side opposite to the substrate 4 as shown in FIG. 17B. It may be a convex polygonal shape. In short, the width of the groove 122 in the direction orthogonal to the extending direction of the phosphor layer 111 may be formed so as to decrease toward the bottom of the groove 122. As shown in FIGS. 17A and 17B, by making the bottom of the groove 122 convex toward the light source 2 side, the beam light applied to the bottom of the groove 122 is refracted toward the center of the black stripe 112. Therefore, the effect of suppressing the occurrence of crosstalk can be further enhanced.

As described above, according to the present embodiment, the screen 10 has the stripe-shaped phosphor layer 111 and the screen layer 11 in which the black stripe 112 is formed between the adjacent phosphor layers 111 stacked on the substrate 4. A plurality of prism rows 121 substantially parallel to each other are formed along the extending direction of the phosphor layer 111, and the screen layer 11 is formed such that the prism surface on which the prism rows 121 are formed faces the opposite side of the substrate 4. The prism sheet 12 is disposed on the prism sheet 12, and a groove 122 having a width that decreases toward the bottom is formed in the prism sheet 12 at a position corresponding to the black stripe 112 of the prism surface.

Of the beam light irradiated to the position on the prism sheet 12 corresponding to the black stripe 112, the beam light irradiated to the inclined surface of the groove part 122 is refracted toward the phosphor layer 111 and is irradiated to the bottom part of the groove part 122. The light is refracted toward the black stripe 112, so that the expansion of the beam diameter is suppressed. Therefore, it is possible to suppress the occurrence of crosstalk due to the simultaneous incidence of light beams on the adjacent phosphor layers 111 that output visible light of different colors, and to prevent the color purity from being lowered.

As mentioned above, although this invention was demonstrated with reference to embodiment, this invention is not limited to the said embodiment. Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the present invention.

This application claims priority based on Japanese application 2011-172967 filed on August 8, 2011, the entire disclosure of which is incorporated herein.

Claims

A substrate,
A screen layer laminated on the substrate;
A prism sheet disposed on the screen layer,
The screen layer has a plurality of phosphor layers and a black stripe disposed between adjacent ones of the phosphor layers included in the plurality of phosphor layers,
The prism sheet has a prism surface on the side opposite to the substrate,
The prism surface has a plurality of prism rows and a groove portion disposed at a position corresponding to the black stripe,
The said groove part is a screen which has a structure where the width | variety of the said groove part becomes small toward the bottom part of the said groove part.
The screen of claim 1.
The prism surface is a screen covered with air or a material having a lower refractive index than the material of the prism.
The screen according to claim 1 or 2,
The screen has a width at the bottom of the groove that is greater than or equal to the width of the black stripe.
The screen according to any one of claims 1 to 3,
The inclination angle of the inclined surface of the groove portion with respect to the screen layer is an inclination angle at which the light output from the phosphor layer to the opposite side of the substrate and reflected by the inclined surface of the groove is reflected to the substrate side by the prism row. A screen.
The screen according to any one of claims 1 to 4,
A low refractive index layer having a lower refractive index than that of the prism sheet is formed between the screen layer and the prism sheet, and the fluorescent light from a direction orthogonal to the screen layer is irradiated to the inclined surface of the groove. The inclination angle of the beam light for exciting the body layer is θ 1 , the inclination angle of the inclined surface of the groove portion with respect to the screen layer is θ 2, and is orthogonal to the screen layer of the beam light refracted at the inclined surface of the groove portion. When the inclination angle from the direction is θ 3 , the refractive index of the surface of the prism surface is n 1 , the refractive index of the prism sheet is n 2, and the refractive index of the low refractive index layer is n 3 , the groove portion The screen is configured such that the maximum value of the inclination angle θ 2 of the inclined surface with respect to the screen layer satisfies the formula (1).
The screen according to any one of claims 1 to 5,
The screen has a convex curved surface as an inclined surface of the groove.
The screen according to any one of claims 1 to 5,
The inclined surface of the groove part is a convex polygonal screen.
The screen according to any one of claims 1 to 7,
The screen has a convex curved surface at the bottom of the groove.
The screen according to any one of claims 1 to 7,
The bottom of the groove is a convex polygonal screen.
A screen according to any one of claims 1 to 9,
A light source provided on the rear side of the screen for outputting beam light;
And an optical scanning unit that scans the beam light output from the light source and irradiates the screen with light.