JP2015014765A - Screen and display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that since projection light projected to an outer frame part positioned at the outer peripheral part of a display part of a screen to which video light is projected is reflected and diffused, it is recognized as a video or stray light by a viewer, and that external light such as sunlight or illumination light made incident from the outside such as a window is reflected and diffused by the outer frame part.SOLUTION: The screen includes an outer frame part 101 positioned so as to surround the periphery of the display part on the same surface as the display part which reflects video light and displays a video, and equipped with a light absorption layer 13 which absorbs light.

Description

  The present invention relates to a screen structure on which image light is projected and a display device using the screen.

  Projection display devices such as projectors project image light emitted from an optical engine onto a screen. “Image light” means light having image information. A “screen” is a surface that displays projected image light. The screen is generally a flat surface, but may be a curved surface, and is not necessarily limited to a flat surface. The screen according to the present invention includes a display unit that is an area of a surface that displays projected image light and an outer frame portion that is an area of a surface that is located outside the display unit and does not display image light. The projection display device displays an image on a display unit of the screen by projecting image light onto the screen.

  For example, a screen used in a front projection projector for conference diffuses light other than video light projected from the projector toward the viewer. The light other than the image light projected from the projector means sunlight or illumination light incident from the outside such as a window. Due to the influence of light other than the image light projected from the projector, the screen looks white as a whole, and as a result, no contrast can be obtained. “Contrast” refers to a light / dark ratio, which is a light / dark ratio between a bright part and a dark part. Consumers tend to desire screens that are difficult to diffuse light other than video light, such as high-contrast applications, for home theater applications, for example. In order to obtain high contrast, it is necessary to make the screen difficult to diffuse sunlight or illumination light incident from the outside such as a window.

  When installing the projector and the screen, it is difficult to project the image light so that the end of the image light completely coincides with the end of the display portion of the screen. For example, when the image light is projected smaller than the size of the display portion of the screen, an area where no image is displayed on the screen occurs. When the image light is projected largely with respect to the size of the display portion of the screen, the entire image is not displayed on the display portion of the screen and is lost. In general, a method is used in which image light including a portion that is not displayed, such as distortion at the edge of an image or noise, is greatly projected with respect to the screen size. This method is called an overscan method.

  In the overscan method, image light is projected outside the display portion of the screen. Video light outside the screen display is called overscan light. For example, Patent Document 1 proposes a configuration of a reflective screen that projects from the front.

Japanese Patent Laying-Open No. 2006-23693 (paragraph 0010)

  In Patent Document 1, the projected image light is reflected to the front by the white resin layer. Most of the incident light on the non-projection side inclined surface is absorbed by the non-projection side inclined surface. A part of the incident light on the non-projection side inclined surface is reflected on the non-projection side inclined surface. The light reflected to the front in the white resin layer and the non-projection side inclined surface is diffused in the transparent diffusion layer. However, when the overscan light hits the screen, the overscan light is recognized by the observer as a noise signal. The noise signal causes discomfort to the observer. In Patent Document 1, since the surface that displays the projected image light is not distinguished from the surface that is located outside the display unit and does not display the image light, the overscan light is directed to the observer side and the image light. Similarly, it is for reflection and diffusion. Further, when the image light is displayed on the entire screen, the overscan light reaches the peripheral surface of the projection display device such as a wall or a ceiling. As a result, stray light is generated. The “stray light” here is light emitted when light other than video light is emitted. Here, the overscan light recognized as a noise signal is also called stray light. Thus, there is a problem that the overscan light hitting the screen is recognized by the observer as stray light.

  The screen according to the present invention includes an outer frame portion that surrounds the display portion on the same surface as the display portion that reflects the image light and displays the image, and has a light absorption layer that absorbs the light. It is characterized by.

  The present invention provides a screen that reduces stray light from the outer frame portion of the screen.

It is a block diagram of the display apparatus which concerns on Embodiment 1 of this invention. It is a front view of the screen which concerns on Embodiment 1 of this invention. It is sectional drawing of a part of screen concerning Embodiment 1 of the present invention. It is sectional drawing of a part of screen concerning Embodiment 1 of the present invention. It is a front view of the screen which concerns on Embodiment 1 of this invention. It is a front view of the screen which concerns on Embodiment 1 of this invention. It is sectional drawing of a part of screen concerning Embodiment 2 of the present invention. It is sectional drawing of a part of screen concerning Embodiment 3 of the present invention. It is a block diagram of the display apparatus which concerns on Embodiment 4 of this invention.

Embodiment 1 FIG.
FIG. 1 is a configuration diagram of a display device according to Embodiment 1 for carrying out the present invention. FIG. 2 is a front view of the screen 10. FIG. 3 is a cross-sectional view of a part of the screen 10. FIG. 4 is a cross-sectional view of a part of the screen 10. FIG. 5 is a front view of the screen 10. FIG. 6 is a front view of the screen 10. For ease of explanation, the coordinate axes of XYZ orthogonal coordinates are shown in each figure. In the following description, the front of the screen 10 is the + Z axis direction, and the rear is the −Z axis direction. The plane of the screen 10 is an XY plane composed of an X-axis direction and a Y-axis direction. From the front (+ Z axis direction) of the screen 10 to the rear (−Z axis direction), the right side is the + X axis direction, and the left side is the −X axis direction. The downward direction of the screen 10 (the direction of the ground) is the + Y axis direction, and the upward direction of the screen 10 (the sky direction) is the −Y axis direction. The front is the front side. In FIG. 1, the projection light 4 emitted from the projector 31 is reflected or diffused by the screen 10 and recognized as an image by the observer. The screen 10 is divided into a display unit 100 and an outer frame unit 101. The positional relationship between the display unit 100 and the outer frame unit 101 will be described later with reference to FIG. A part of the display unit 100 is 10a. A part of the outer frame portion 101 is 10b. The display unit 100 in the screen 10 includes a light reflection layer 11, a light diffusion layer 12, and a light absorption layer 13. On the other hand, the light reflection layer 11 and the light diffusion layer 12 are not provided on the outer frame portion 101 of the screen 10 on which the overscan light is projected.

  The configuration and function of the screen 10 will be described in detail. FIG. 2 shows a case where the screen 10 is viewed from the front (+ Z-axis direction). The screen 10 is divided into a display unit 100 and an outer frame unit 101 arranged around the display unit 100 in a frame shape. As shown in FIG. 3, the cross-sectional configuration of the display unit 100 of the screen 10 includes a light reflection layer 11, a light diffusion layer 12, and a light absorption layer 13. A light diffusion layer 12 is disposed in front of the screen 10 (+ Z-axis direction), and a light absorption layer 13 is disposed behind. The light reflection layer 11 is provided at the boundary between the light diffusion layer 12 and the light absorption layer 13. The light reflecting layer 11 has its reflecting surface directed obliquely downward in the front (+ Z axis direction). The boundary between the light diffusion layer 12 and the light reflection layer 11 or the light absorption layer 13 has the shape of a Fresnel lens 14. A “Fresnel lens” is a lens whose thickness is reduced by dividing a normal lens into concentric regions. Here, only the minimum necessary configuration of the display unit 100 of the screen 10 will be described, but a configuration may be added for reasons of manufacturing and improving optical characteristics.

  In the display unit 100, as a function necessary for obtaining good contrast, it is possible to absorb sunlight or illumination light incident from the outside such as a window as much as possible. Further, in the display unit 100, as a function necessary for obtaining a good contrast, only the projection light 4 emitted from the projector 31 is reflected to the viewer side positioned in front of the screen 10 (+ Z axis direction). Can be mentioned. In the display unit 100 including the light reflecting layer 11, the light diffusing layer 12, and the light absorbing layer 13, the projection light 4 emitted from the projector 31 is first diffused by the light diffusing layer 12 and then screened by the light reflecting layer 11. 10 is reflected to the viewer's side located in front of (+ Z axis direction) 10, diffused again by the light diffusion layer 12, and recognized as an image by the viewer. On the other hand, it is desirable that external light such as illumination light or sunlight incident from the outside such as a window is absorbed by the light absorption layer 13 and is not recognized by an observer. That is, when the projection light 4 is not projected from the projector 31, it is desirable that the appearance of the display unit 100 looks dark without diffusing external light or the like. On the other hand, when projecting the projection light 4, it is desirable that the image is efficiently reflected and diffused toward an observer in front of the screen 10 (+ Z axis direction) and recognized as an image.

  Next, the outer frame portion 101 will be described with reference to FIG. The display unit 100 is slightly smaller than the size of the screen 10, and an outer frame unit 101 is provided outside the display unit 100. The reason for this is that, as described above, when the projector 31 and the screen 10 are installed, it is difficult to completely match the image light with the display unit 100 of the screen 10, and the projection light 4 that is larger than the display unit 100 is large. Is projected onto the screen 10. Then, the outer frame 101 absorbs the projection light 4, and the outer frame 101 functions as if it is a frame of the display unit 100.

  At this time, if the projection light 4 is diffused in the outer frame portion 101, it is recognized that an image is also reflected in the outer frame portion, so that the meaning of overscanning is lost. Further, if sunlight or illumination light or the like incident from the outside such as a window is reflected or diffused, the outer frame portion 101 will appear white to the observer. It is undesirable in appearance that the outer frame portion 101 appears white to the viewer. On the other hand, the reason why the projected light 4 is inconvenient in the visual sense even when it is mainly reflected or mainly transmitted by the outer frame portion 101 will be described. First, when the outer frame portion 101 mainly reflects the projection light 4, the reflected projection light 4 hits an indoor wall or ceiling, for example. By further reflecting or diffusing the projected light reflected by the reflected light of the projected light 4 such as an indoor wall or ceiling, the reflected or diffused light becomes stray light. As a result, the observer recognizes that the portion where the reflected projection light 4 is shining is shining. Or an observer will recognize as if the image is reflected. The same applies to the case where the outer frame portion 101 mainly transmits the projection light 4. That is, the transmitted light that has passed through hits, for example, an indoor wall or ceiling, and becomes stray light. As a result, the observer recognizes that the portion of the transmitted light that has been transmitted, such as the indoor wall or ceiling, is shining. Or an observer will recognize as if the image is reflected. Therefore, the outer frame portion 101 desirably has a structure that does not reflect, transmit, or diffuse the projection light 4.

  As described above, the display unit 100 in the screen 10 is required to have a function of absorbing illumination light or sunlight from the outside such as a window while reflecting or diffusing the projection light 4 toward the viewer. The outer frame portion 101 is required to have a function of absorbing any of projection light 4, illumination light, and sunlight from the outside such as a window.

  Next, the appearance of the screen 10 when the projection light 4 is not projected from the projector 31 will be described. FIG. 5 shows the screen 10 viewed from the front (+ Z-axis direction) in a state where the display is off. The function of the screen 10 is divided into a display unit 100 and an outer frame unit 101. When the projector 31 is not projecting the projection light 4, that is, when the display is turned off as the display device, it is desirable that the screen 10 does not easily recognize the boundary between the display unit 100 and the outer frame unit 101. Furthermore, it is desirable that the screen 10 has no difference in appearance in each region. The reason is that when the outer frame 101 is different in appearance from the display unit 100, the outer frame 101 is recognized as if it is a frame of the screen 10, and a frame unnecessary as a display device impairs the appearance. FIG. 6 shows the screen 10 viewed from the front (+ Z-axis direction) in a state where the display is on. When the projector 31 is projecting the projection light 4, that is, when the display is turned on as a display device, it is naturally desirable that an unnecessary noise signal or the like is not displayed on the outer frame portion 101 of the screen 10.

  In order to provide the above-described function, a method of fixing another component only to the outer frame portion 101 can be easily considered. In the method of fixing another component only to the outer frame 101, it is difficult to eliminate the difference in appearance between the display unit 100 and the outer frame 101. Another part fixed only to the outer frame portion 101 is recognized by the observer as if it were a frame of the screen 10. As a result, another component fixed only to the outer frame portion 101 deteriorates the appearance of the screen. The present invention solves such a problem without adding another part by adopting the configuration of the screen 10 described below.

  An example of a method for manufacturing the display unit 100 of the screen 10 will be described. As described above, the display unit 100 includes the light reflection layer 11, the light diffusion layer 12, and the light absorption layer 13. FIG. 3 is an enlarged cross-sectional view of 10a, which is a part of the display unit 100 in FIG. The Fresnel lens 14 of the light diffusion layer 12 is made of a photocurable resin or the like. Here, for the sake of simplicity, the light diffusion layer 12 is assumed to have the shape of the Fresnel lens 14. However, for reasons of manufacturing, the light diffusion layer 12 and the Fresnel lens 14 may be configured as separate layers. Possible. Next, the light reflecting layer 11 is generated on the surface of the Fresnel lens 14. As this method, for example, a method of generating a metal layer such as aluminum on the surface of the Fresnel lens 14 by vacuum deposition may be used. As a method of forming the light absorption layer 13, a method of using a resin in which a black pigment such as carbon particles is dispersed is used.

  The display unit 100 of the screen 10 manufactured in this manner has a function of absorbing illumination light or sunlight from the outside such as a window while reflecting and diffusing the projection light 4 toward the viewer. As shown in FIG. 3, illumination light or sunlight from the outside such as a window enters the screen 10 from an obliquely upward direction. For this reason, illumination light or sunlight from the outside such as a window is directly absorbed by the light absorption layer 13. When illumination light or sunlight from the outside such as a window is reflected by the light reflecting layer 11, the light is absorbed by the light absorbing layer 13 or goes downward. For this reason, light is not reflected on the observer side, and illumination light incident on the screen 10 or sunlight from the outside such as a window is not recognized by the observer. On the other hand, in the state in which the projection light 4 is projected, the projection light 4 travels from the obliquely downward direction to the screen 10 as shown in FIG. Therefore, the projection light 4 is reflected by the light reflecting layer 11 without being absorbed by the light absorbing layer 13. Further, the projection light 4 is appropriately diffused by the light diffusion layer 12 and reaches the observer, and is recognized as an image.

  In the outer frame portion 101, a necessary function can be obtained by adopting a configuration in which the light reflection layer 11 and the light diffusion layer 12 are not provided. FIG. 4 is an enlarged cross-sectional view of a part 10b of the outer frame portion 101 of the screen 100 in which the light absorption layer 13 is provided and the light reflection layer 11 and the light diffusion layer 12 are not formed. The light absorption layer 13 is disposed from the front (+ Z axis direction) to the rear of the screen 10. In this configuration, the projection light 4 projected on the outer frame portion 101 is not reflected or diffused. For this reason, the projection light 4 is prevented from being diffused by the light diffusion layer 12 and being recognized as an image by the observer. The front surface (+ Z-axis direction) of the light absorption layer 13 in the outer frame portion 101 and the front surface (+ Z-axis direction) of the light diffusion layer 12 in the display portion 100 are the same surface.

  The Fresnel lens 14 described above has concentric grooves and condenses light at one point. As described above, the Fresnel lens 14 in the present invention needs to have a structure in which the light reflected by the light reflecting layer 11 is directed downward. Therefore, the Fresnel lens 14 has a structure in which the upper part is cut out from the center of the lens. Alternatively, a linear Fresnel lens may be used in which the grooves are parallel straight lines and collect light on a straight line. In the drawings used in the above description, the surfaces of the display unit 100 and the outer frame unit 101 are flat surfaces, but may be surfaces having slight unevenness or curved surfaces.

  As described above, the present invention does not generate stray light due to reflection or diffusion of the projection light 4 projected on the outer frame portion. Further, the present invention does not project an image on the outer frame portion 101 of the screen 10. Furthermore, the present invention does not impair the appearance of the screen 10 even when no image light is projected.

Embodiment 2
In the present embodiment, in the outer frame portion 101 in the first embodiment, the light diffusion layer 12 is formed in front of the light absorption layer 13 (+ Z-axis direction). The outer frame portion 101 in the present embodiment does not include the light reflection layer 11 and the Fresnel lens 14 that the display portion 100 has.

  FIG. 7 is an enlarged cross-sectional view of a part 10b of the outer frame portion 101 of the screen 100 in which the light diffusion layer 12 and the light absorption layer 13 are provided and the light reflection layer 11 and the Fresnel lens 14 are not formed. is there. A light diffusion layer 12 is disposed in front of the screen 10 (+ Z-axis direction), and a light absorption layer 13 is disposed behind. In this configuration, since the light reflecting layer 11 and the Fresnel lens 14 are not formed, the projection light 4 projected on the outer frame portion 101 is not reflected by the light reflecting layer 11 and the Fresnel lens 14. Therefore, the projection light 4 is prevented from being recognized as an image by the observer by being reflected by the light reflection layer 11. Even in the configuration in which the light reflection layer 11 is not provided, the projection light 4 is slightly reflected at the interface between the Fresnel lens 14 and the light diffusion layer 12 and may be recognized as an image for the observer. The outer frame portion 101 of this configuration can also prevent the projection light 4 from being slightly reflected at the interface between the Fresnel lens 14 and the light diffusion layer 12 and being recognized as an image by the observer. The front surface (+ Z-axis direction) of the light diffusion layer 12 in the outer frame portion 101 and the front surface (+ Z-axis direction) of the light diffusion layer 12 in the display portion 100 are the same surface.

  Also in this embodiment, stray light due to reflection or diffusion of the projection light 4 projected on the outer frame portion is not generated, as in the above embodiment. Further, the present invention does not project an image on the outer frame portion 101 of the screen 10. Furthermore, the present invention does not impair the appearance of the screen 10 even when no image light is projected.

Embodiment 3
In the present embodiment, the Fresnel lens 14 is formed on the light diffusion layer 12 in the outer frame portion 101 in the first embodiment. That is, in the method for manufacturing the display unit 100 of the screen 10 described above, a method in which the light reflecting layer 11 is not formed only on the outer frame unit 101 is employed. Specifically, for example, in the method of forming the light reflecting layer 11 by depositing aluminum by vacuum deposition, the outer frame portion 101 is masked so that aluminum is not deposited. As another method, for example, in the method of forming the light reflecting layer 11 with a resin in which a pigment such as titanium dioxide having a high light reflectance is dispersed, the outer frame portion 101 is masked so that the resin is not formed. With this configuration, in the present embodiment, unlike the first and second embodiments, the display unit 100 and the outer frame unit 101 can be integrally formed.

  FIG. 8 is an enlarged cross-sectional view of a part 10b of the outer frame portion 101 of the screen 100 manufactured as described above. A light diffusion layer 12 is disposed in front of the screen 10 (+ Z-axis direction), and a light absorption layer 13 is disposed behind. The boundary between the light diffusion layer 12 and the light absorption layer 13 has the shape of the Fresnel lens 14. The lens surface of the Fresnel lens 14 has its surface facing obliquely downward in the front (+ Z-axis direction) like the reflection surface of the light reflection layer 11 in the display unit 100. The projection light 4 projected on the outer frame portion 101 is diffused by the light diffusion layer 12 and absorbed by the light absorption layer 13. For this reason, the projection light 4 projected on the outer frame portion 101 is not recognized by the observer as an image. On the other hand, sunlight or illumination light incident from the outside such as a window is absorbed by the light absorption layer 13 and does not impair the appearance of the screen. The front surface (+ Z-axis direction) of the light diffusion layer 12 in the outer frame portion 101 and the front surface (+ Z-axis direction) of the light diffusion layer 12 in the display portion 100 are the same surface.

  Also in this embodiment, stray light due to reflection or diffusion of the projection light 4 projected on the outer frame portion is not generated, as in the above embodiment. Further, the present invention does not project an image on the outer frame portion 101 of the screen 10.

Embodiment 4
In the present embodiment, as shown in FIG. 9, a display device 41 is obtained by combining the screen 10 of the first to third embodiments and the short focus projector 32. In the above configuration, the observer sees the screen from the center or from the top. When the screen in a state where the image light is not emitted from the center or the upper part is viewed, the display unit 100 has a black appearance due to the light diffusion layer 12 and the light absorption layer 13 on the back surface. In this case, the outer frame portion 101 has a black appearance due to the light absorption layer 13. Therefore, there is no difference in appearance between the display unit 100 and the outer frame unit 101 even in a screen in a state where no image light is emitted.

  DESCRIPTION OF SYMBOLS 10 Screen, 100 Display part, 101 Outer frame part, 11 Light reflection layer, 12 Light diffusion layer, 13 Light absorption layer, 14 Fresnel lens, 4 Projection light, 31 Projector, 32 Short focus type projector, 41 Display apparatus

Claims (4)

  A screen comprising: an outer frame portion having a light absorbing layer that absorbs light and is positioned around the display portion on the same surface as a display portion that reflects image light and displays an image. The screen according to claim 1, wherein the outer frame portion includes a light diffusion layer that exists on the front side of the light absorption layer and diffuses light. The screen according to claim 2, wherein the light diffusion layer has a Fresnel lens shape. A display device comprising the screen according to any one of claims 1 to 3.

Images