JP2009162876A - Projector screen - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projector screen capable of performing a high-contrast and high-gradation display when using it together with a projector. <P>SOLUTION: Regarding the projector screen 32 for displaying an image projected from the projector 31 thereon, a display medium is packed in a cavity between two base plates, at least one of which is transparent, and the display medium is moved so as to display information on an image or the like. The projector screen is constituted of an information display panel 33 that can display the same image as the image projected from the projector. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a projector screen for projecting an image projected from a projector.

  Conventionally, a projector screen used for projecting an image projected from a projector has been used. Among various projector screens, there is known a projector screen that has a simple configuration, a wide viewing angle, and capable of projecting a bright image even under illumination (for example, see Patent Document 1).

JP 2006-84586 A

  Since the conventional projector screen described above has a function of reflecting and displaying an image projected from the projector, it is usually configured as a white or black screen or the like. In the conventional projector screen having such a structure, the contrast cannot be improved on the screen side. In addition, the conventional projector screen can display an image only at a contrast lower than the contrast that can be realized by the projector display element. For this reason, display using a conventional projector and a projector screen has a problem that high contrast and high gradation cannot be displayed.

  An object of the present invention is to solve the above-mentioned problems and to provide a projector screen capable of displaying high contrast and high gradation when used in combination with a projector.

  The projector screen according to the present invention is a projector screen for projecting an image projected from a projector, in which a display medium is sealed in a space between two substrates, at least one of which is transparent, and the display medium is moved to display an image, etc. This is a projector screen for displaying the above information, and is configured by an information display panel capable of displaying the same image as the image projected by the projector.

  As a preferred example of the projector screen according to the present invention, it is configured from a plurality of information display panels, and is configured such that one pixel of an image projected from the projector matches an integer multiple pixel of the information display panel. There is.

  According to the present invention, the projector screen is a projector screen for enclosing a display medium in a space between two substrates, at least one of which is transparent, and moving the display medium to display information such as an image. By configuring the information display panel that can display the same image as the image projected by the projector, it is possible to obtain a projector screen that can display high contrast and high gradation when used in combination with the projector. .

  First, a configuration of a charged particle movement type information display panel will be described as an example of an information display panel used as a projector screen of the present invention. In the information display panel, an electric field is applied to a display medium configured as a particle group including particles having at least an optical reflectance and a charging property sealed in a space between two opposing substrates. Along with the applied electric field direction, the display medium is attracted by an electric field force or a Coulomb force, and the display medium is moved by a change in the electric field direction, whereby information such as an image is displayed. Therefore, it is necessary to design the information display panel so that the display medium can move uniformly and maintain stability when rewriting the display repeatedly or when displaying the display information continuously. Here, the force applied to the particles constituting the particle group serving as the display medium includes, in addition to the force attracted by the Coulomb force between the particles, the electric mirror image force between the electrode and the substrate, intermolecular force, liquid crosslinking force, gravity Can be considered.

 The structure of the charged particle movement type information display panel used as the projector screen of the present invention will be described with reference to FIGS. 1 (a), (b) to FIGS. 4 (a), 4 (b), 5, and 6. FIG.

  In the example shown in FIGS. 1 (a) and 1 (b), the particles are configured as a particle group including particles having at least optical reflectance and chargeability, and are configured as particle groups having different optical reflectance and charging characteristics. At least two or more kinds of display media 3 (here, a white display medium 3W composed of a group of white particles 3Wa for display and a black display medium 3B composed of a group of black particles 3Ba for display) are formed of partition walls 4. In each cell, the substrates 1, 2, and 2 according to the electric field generated by applying a voltage between the electrode 5 (individual electrode) provided on the substrate 1 and the electrode 6 (individual electrode) provided on the substrate 2. Move vertically. Then, as shown in FIG. 1A, the white display medium 3W is visually recognized by the observer and white dot display is performed, or as shown in FIG. 1B, the black display medium 3B is visually recognized by the observer. Black dots are displayed. In addition, in FIG. 1 (a), (b), the partition in front is abbreviate | omitted.

  In the example shown in FIGS. 2 (a) and 2 (b), the particles are configured as particle groups including particles having at least optical reflectance and chargeability, and are configured as particle groups having different optical reflectance and charging characteristics. At least two or more kinds of display media 3 (here, a white display medium 3W composed of a group of white particles 3Wa for display and a black display medium 3B composed of a group of black particles 3Ba for display) are formed of partition walls 4. In each cell, the substrates 1, 2, and 2 are formed according to the electric field generated by applying a voltage between the electrode 5 (line electrode) provided on the substrate 1 and the electrode 6 (line electrode) provided on the substrate 2. Move vertically. Then, as shown in FIG. 2 (a), the white display medium 3W is visually recognized by the observer and white dot display is performed, or as shown in FIG. 2 (b), the black display medium 3B is visually recognized by the observer. Black dots are displayed. In addition, in FIG. 2 (a), (b), the partition in front is abbreviate | omitted.

  In the example shown in FIGS. 3A and 3B, an example of color display in which a display unit (1 dot) is constituted by three cells is shown. In the example shown in FIGS. 3A and 3B, as the display medium, all of the cells 21-1 to 21-3 are filled with the white display medium 3W and the black display medium 3B, and the first cell 21-1. A red color filter 22R is provided on the viewer side, a green color filter 22G is provided on the viewer side of the second cell 21-2, a blue color filter 22B is provided on the viewer side of the third cell 21-3, A display unit (one dot) is composed of three cells, the first cell 21-1, the second cell 21-2, and the third cell 21-3. In this example, when performing color display, as shown in FIG. 3A, the white display medium 3W is moved in the first cell 21-1 to the third cell 21-3 to the viewer side. Thus, white dots are displayed to the observer, or, as shown in FIG. 3B, the black color is displayed in all of the first cell 21-1 to the third cell 21-3 on the observer side. By moving the medium 3B, black dots are displayed to the observer. In addition, in FIG. 3 (a), (b), the partition in front is abbreviate | omitted. Multicolor display can be performed by moving the display medium in each cell.

  In the example shown in FIGS. 4A and 4B, one type of display medium 3 (here, particles of display white particles 3Wa) configured as a particle group including particles having at least optical reflectance and chargeability. A white display medium 3W consisting of a group) in each cell formed by the partition walls 4, according to the electric field generated by applying a voltage between the electrode 5 and the black electrode 6 provided on the substrate 1, It moves in the direction parallel to the substrates 1 and 2. Then, as shown in FIG. 4A, the white display medium 3W is visually recognized by the observer and white dot display is performed, or as shown in FIG. 4B, the color of the black electrode 6 is changed by the observer. The black dots are displayed by visually recognizing. In addition, in the example shown to Fig.4 (a), (b), the partition in front is abbreviate | omitted. The color of the display medium and the color exhibited by the electrodes are not limited to this combination. Further, a color plate can be arranged under the transparent electrode to display the color of the color plate.

  In the example shown in FIG. 5, a microcapsule 8 in which a white display medium 3 </ b> W and a black display medium 3 </ b> B are filled as a display medium together with an insulating liquid 7 is disposed in the space between the substrates 1 and 2. In this example, the display medium in the microcapsule is moved in accordance with the electric field generated by applying a voltage between the electrode 5 provided on the substrate 1 and the electrode 6 provided on the substrate 2, and white / black Dot display. The example shown in FIG. 5 corresponds to the positional relationship between the microcapsule 8 and the individual electrodes 5 and 6. In addition, in FIG. 5, the partition in front is abbreviate | omitted.

  In the example shown in FIG. 6, the space between the substrates 1 and 2 is filled with microcapsules 8 filled with white display medium 3W and black display medium 3B as display media together with insulating liquid 7. In this example, the display medium in the microcapsule is moved in accordance with the electric field generated by applying a voltage between the electrode 5 provided on the substrate 1 and the electrode 6 provided on the substrate 2, and white / black Dot display. In the example shown in FIG. 6, the positional relationship between the microcapsule 8 and the individual electrodes 5 and 6 is not compatible. In FIG. 6, the front partition is omitted.

  As described above, the projector screen of the present invention is characterized in that, as described above, a display medium is sealed in a space between two substrates, at least one of which is transparent, and the display medium is moved to display information such as an image. The projector screen to be displayed is composed of an information display panel capable of displaying the same image as the image projected by the projector.

  FIG. 7 is a diagram for explaining an example of the projector screen according to the present invention. In the example shown in FIG. 7, 31 is a projector for projecting an image, and 32 is a projector screen configured by fixing an information display panel 33 to a frame 34. The information display panel 33 constituting the projector screen 32 is configured to be able to display the same image as the image projected by the projector 31. In this example, since the projector 31 projects an image on the screen 32, the information display panel 33 can display the same image in addition to the image projected by the projector 31. A high gradation display with contrast can be performed.

  In order to achieve the above-described present invention, the image projected by the projector 31 on the screen 32 and the image displayed by the information display panel 33 constituting the screen 32 are synchronized, and both images are displayed. The constituent pixels and the pixels need to be displayed correspondingly. FIGS. 8A and 8B are diagrams for explaining the relationship between the pixels of the image projected by the projector 31 and the pixels of the image displayed by the information display panel 33 in the present invention. In the example shown in FIG. 8A, one pixel 42 of the image 41 projected by the projector 31 and one pixel 44 of the image 43 displayed by the information display panel 33 are displayed in association with each other. Further, in the example shown in FIG. 8B, it is composed of one pixel 42 of the image 41 projected by the projector 31 and an integer multiple of the image 43 displayed by the information display panel 33, here, 4 × 2 × 2. The image area 45 to be displayed is displayed correspondingly. Of course, the number of integer multiple pixels is not limited to 2 × 2 depending on the setting.

  Actually, when a figure as shown in FIG. 9 is displayed so that the contrast becomes 1000: 1 on a conventional screen and the screen is replaced with the screen 32 of the present invention, the contrast becomes 5000: 1. From this, it can be seen that image display with high contrast can be achieved.

  Hereinafter, each member which comprises the information display panel used as a projector screen of this invention is demonstrated.

  As the substrate, at least one substrate is a transparent substrate on which the color of the display medium can be confirmed from the outside of the panel, and a material having high visible light transmittance and good heat resistance is preferable. The back substrate as the other substrate may be transparent or opaque. Examples of substrate materials include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethylene (PE), polycarbonate (PC), polyimide (PI), polyethersulfine (PES), acrylic polymer substrates Alternatively, a glass sheet, a quartz sheet, a metal sheet, or the like is used, and a transparent one is used on the display surface side. The thickness of the substrate is preferably from 2 to 2000 μm, more preferably from 5 to 1000 μm. If it is too thin, it will be difficult to maintain the strength and the uniform spacing between the substrates, and if it is thicker than 2000 μm, it will be inconvenient for a thin screen. is there.

  As a material for forming an electrode provided on the substrate, metals such as aluminum, silver, nickel, copper, and gold, indium tin oxide (ITO), indium zinc oxide (IZO), aluminum-doped zinc oxide (AZO), indium oxide, conductive Examples include conductive metal oxides such as conductive tin oxide, antimony tin oxide (ATO), and conductive zinc oxide, and conductive polymers such as polyaniline, polypyrrole, and polythiophene, which are appropriately selected and used. As a method for forming an electrode, a method of patterning and forming the above-exemplified materials into a thin film by a sputtering method, a vacuum deposition method, a CVD (chemical vapor deposition) method, a coating method, etc., a method of laminating a metal foil (for example, a rolled copper foil, etc.) Or a conductive agent mixed with a solvent or a synthetic resin binder and applied to form a pattern. The electrode provided on the viewing side (display surface side) substrate needs to be transparent, but the electrode provided on the back side substrate does not need to be transparent, and the electrode of the present invention is provided. In any case, the above-mentioned material that is conductive and capable of pattern formation can be suitably used. In addition, the electrode thickness should just be sufficient if electroconductivity is ensured and there is no trouble in light transmittance, and 0.01-10 micrometers, Preferably 0.05-5 micrometers is suitable. The material and thickness of the electrode provided on the back side substrate are the same as those of the electrode provided on the display surface side substrate described above, but need not be transparent. In this case, the external voltage input may be superimposed with direct current or alternating current.

The shape of the partition provided on the substrate as required is appropriately set appropriately depending on the type of display medium involved in display, the shape of the electrode to be arranged, and the arrangement, and is not limited in general, but the width of the partition is 2 to 100 μm. The height of the partition wall is adjusted to 10 to 500 μm, preferably 10 to 200 μm, more preferably 10 to 100 μm, and particularly preferably 10 to 50 μm. The height of the partition wall is matched with the substrate interval, but the height of the partition wall can be partially made lower than the substrate interval.
In forming the partition wall, a both-rib method in which ribs are formed on each of the opposing substrates 1 and 2 and then bonded, and a single-rib method in which ribs are formed only on one substrate are conceivable. Any method is used in the present invention.
As shown in FIG. 10, the cells formed by the partition walls made up of these ribs are exemplified by a square shape, a triangular shape, a line shape, a circular shape, and a hexagonal shape as viewed from the plane of the substrate. And a mesh shape. It is better to make the portion corresponding to the cross section of the partition wall visible from the display surface side (the area of the cell frame) as small as possible, and the display becomes clearer.
Examples of the method for forming the partition include a mold transfer method, a screen printing method, a sand blast method, a photolithography method, and an additive method. Any of these methods can be suitably used for an information display panel mounted on the information display device of the present invention, and among these, a photolithography method using a resist film and a mold transfer method are suitably used.

Next, the chargeable particles (hereinafter also referred to as display particles) constituting the display medium in the charged particle movement type information display panel that is the subject of the present invention will be described. The display particles can be used as they are by using only the display particles to form a display medium, or by combining with other particles to form a display medium.
The particles can contain a charge control agent, a colorant, an inorganic additive, and the like, if necessary, in the resin as the main component. Examples of resins, charge control agents, colorants, and other additives will be given below.

  Examples of the resin include urethane resin, urea resin, acrylic resin, polyester resin, acrylic urethane resin, acrylic urethane silicone resin, acrylic urethane fluororesin, acrylic fluororesin, silicone resin, acrylic silicone resin, epoxy resin, polystyrene resin, styrene Acrylic resin, polyolefin resin, butyral resin, vinylidene chloride resin, melamine resin, phenol resin, fluororesin, polycarbonate resin, polysulfone resin, polyether resin, polyamide resin and the like can be mentioned, and two or more kinds can be mixed. In particular, acrylic urethane resin, acrylic silicone resin, acrylic fluororesin, acrylic urethane silicone resin, acrylic urethane fluororesin, fluororesin, and silicone resin are suitable from the viewpoint of controlling the adhesive force with the substrate.

  The charge control agent is not particularly limited. Examples of the negative charge control agent include salicylic acid metal complexes, metal-containing azo dyes, metal-containing oil-soluble dyes (including metal ions and metal atoms), and quaternary ammonium salt systems. Examples thereof include compounds, calixarene compounds, boron-containing compounds (benzyl acid boron complexes), and nitroimidazole derivatives. Examples of the positive charge control agent include nigrosine dyes, triphenylmethane compounds, quaternary ammonium salt compounds, polyamine resins, imidazole derivatives, and the like. In addition, metal oxides such as ultrafine silica, ultrafine titanium oxide, ultrafine alumina, nitrogen-containing cyclic compounds such as pyridine and derivatives and salts thereof, various organic pigments, resins containing fluorine, chlorine, nitrogen, etc. are also charged. It can also be used as a control agent.

  As the colorant, various organic or inorganic pigments and dyes as exemplified below can be used.

Examples of the black colorant include carbon black, copper oxide, manganese dioxide, aniline black, activated carbon and the like.
Examples of blue colorants include C.I. I. Pigment blue 15: 3, C.I. I. Pigment Blue 15, Bituminous Blue, Cobalt Blue, Alkaline Blue Lake, Victoria Blue Lake, Phthalocyanine Blue, Metal-free Phthalocyanine Blue, Phthalocyanine Blue Partial Chlorides, Fast Sky Blue, Indanthrene Blue BC, and the like.
Examples of red colorants include bengara, cadmium red, red lead, mercury sulfide, cadmium, permanent red 4R, risor red, pyrazolone red, watching red, calcium salt, lake red D, brilliant carmine 6B, eosin lake, rhodamine lake B, Alizarin Lake, Brilliant Carmine 3B, C.I. I. Pigment Red 2 etc.

Yellow colorants include chrome yellow, zinc yellow, cadmium yellow, yellow iron oxide, mineral first yellow, nickel titanium yellow, navel yellow, naphthol yellow S, Hansa Yellow G, Hansa Yellow 10G, Benzidine Yellow G, Benzidine Yellow GR, Quinoline Yellow Lake, Permanent Yellow NCG, Tartrazine Lake, C.I. I. Pigment Yellow 12 etc.
Examples of green colorants include chrome green, chromium oxide, pigment green B, C.I. I. Pigment Green 7, Malachite Green Lake, Final Yellow Green G, etc.
Examples of the orange colorant include red chrome yellow, molybdenum orange, permanent orange GTR, pyrazolone orange, Vulcan orange, indanthrene brilliant orange RK, benzidine orange G, indanthrene brilliant orange GK, C.I. I. Pigment Orange 31 etc.
Examples of purple colorants include manganese purple, first violet B, and methyl violet lake.
Examples of white colorants include zinc white, titanium oxide, antimony white, and zinc sulfide.

  Examples of extender pigments include barite powder, barium carbonate, clay, silica, white carbon, talc, and alumina white. Examples of various dyes such as basic, acidic, disperse, and direct dyes include nigrosine, methylene blue, rose bengal, quinoline yellow, and ultramarine blue.

Examples of inorganic additives include titanium oxide, zinc white, zinc sulfide, antimony oxide, calcium carbonate, lead white, talc, silica, calcium silicate, alumina white, cadmium yellow, cadmium red, cadmium orange, titanium yellow, Examples include bitumen, ultramarine blue, cobalt blue, cobalt green, cobalt violet, iron oxide, carbon black, manganese ferrite black, cobalt ferrite black, copper powder, and aluminum powder.
These pigments and inorganic additives can be used alone or in combination. Of these, carbon black is particularly preferable as the black pigment, and titanium oxide is preferable as the white pigment. The display agent of a desired color can be produced by blending the colorant.

  The display particles of the present invention (hereinafter also referred to as particles) preferably have an average particle diameter d (0.5) in the range of 1 to 20 μm and are uniform and uniform. If the average particle diameter d (0.5) is larger than this range, the display is not clear. If the average particle diameter d (0.5) is smaller than this range, the cohesive force between the particles becomes too large, which hinders movement as a display medium.

Further, in the present invention, regarding the particle size distribution of each display particle, the particle size distribution Span represented by the following formula is set to less than 5, preferably less than 3.
Span = (d (0.9) −d (0.1)) / d (0.5)
(However, d (0.5) is a numerical value expressing the particle diameter in μm that 50% of the particles are larger than this and 50% is smaller than this, and d (0.1) is a particle in which the ratio of the smaller particles is 10%. (Numerical value expressed in μm, and d (0.9) is a numerical value expressed in μm for a particle diameter of 90% or less.)
By keeping Span within a range of 5 or less, the size of each particle is uniform, and movement as a uniform display medium becomes possible.

  Furthermore, it is important that the ratio of d (0.5) of particles having the minimum diameter to d (0.5) of particles having the maximum diameter among the display particles used is 10 or less. Even if the particle size distribution Span is reduced, particles with different charging characteristics move in opposite directions, so that the particle size is close to each other and each particle can be easily moved in the opposite direction by the equivalent amount. This is within this range.

The particle size distribution and the particle size can be obtained from a laser diffraction / scattering method or the like. When laser light is irradiated onto particles to be measured, a light intensity distribution pattern of diffracted / scattered light is spatially generated, and this light intensity pattern has a corresponding relationship with the particle diameter, so that the particle diameter and particle diameter distribution can be measured. .
Here, the particle size and particle size distribution in the present invention are obtained from a volume-based distribution. Specifically, using a Mastersizer2000 (Malvern Instruments Ltd.) measuring instrument, particles are introduced into a nitrogen stream, and the attached analysis software (software based on volume-based distribution using Mie theory) The diameter and particle size distribution can be measured.

Furthermore, when a display medium configured as a group of particles containing charged particles is driven in a gas space, it is important to manage the gas in the gap surrounding the display medium between the panel substrates, and display stability. Contributes to improvement. Specifically, it is important that the relative humidity at 25 ° C. is 60% RH or less, and preferably 50% RH or less for the humidity of the gas in the gap.
This gap portion refers to the electrodes 5 and 6 from the portion sandwiched between the opposing substrate 1 and substrate 2 in FIGS. 1A, 1B to 4A, 4B, 5 and 6, respectively. (When electrodes are provided inside the substrate), the occupied portion of the display medium 3, the occupied portion of the partition 4 (when the partition is provided), and the gas portion in contact with the so-called display medium excluding the panel seal portion And
The gas in the gap is not limited as long as it is in the humidity region described above, but dry air, dry nitrogen, dry argon, dry helium, dry carbon dioxide, dry methane, and the like are preferable. This gas needs to be sealed in the panel so that the humidity is maintained. For example, the display medium is filled and the panel is assembled in a predetermined humidity environment. It is important to apply a sealing material and a sealing method to prevent it.

The distance between the substrates in the information display panel of the present invention is not limited as long as the display medium can be moved and the contrast can be maintained, but is usually 10 to 500 μm, preferably 10 to 200 μm, more preferably 10 to 100 μm, particularly preferably. Is adjusted to 10 to 50 μm.
The volume occupancy of the display medium in the gas space between the opposing panel substrates is preferably 5 to 70%, more preferably 5 to 60%. When it exceeds 70%, the movement as a display medium is hindered, and when it is less than 5%, the contrast tends to be unclear.

  According to the projector screen of the present invention, when used in combination with a dedicated projector, the projector screen can be suitably used as a projector screen capable of displaying high contrast and high gradation.

(A), (b) is a figure which shows an example of the fundamental structure of the information display panel used as a screen for projectors of this invention. (A), (b) is a figure which shows the other example of the fundamental structure of the information display panel used as a screen for projectors of this invention. (A), (b) is a figure which shows the further another example of the fundamental structure of the information display panel used as a screen for projectors of this invention. (A), (b) is a figure which shows the further another example of the fundamental structure of the information display panel used as a screen for projectors of this invention. It is a figure which shows the further another example of the fundamental structure of the information display panel used as a screen for projectors of this invention. It is a figure which shows the further another example of the fundamental structure of the information display panel used as a screen for projectors of this invention. It is a figure for demonstrating an example of the screen for projectors of this invention. (A), (b) is a figure for demonstrating the relationship between the pixel of the image which the projector in this invention projects, and the pixel of the image which an information display panel displays, respectively. It is a figure which shows the display pattern in an Example. It is a figure which shows an example of the shape of the partition in the information display panel of this invention.

Explanation of symbols

1, 2 Substrate 3 Display medium (particle group)
3W white display medium
3B Black display medium 3Wa White display particles
3Ba Black display particles
4 Bulkhead 5 and 6 Electrode 7 Insulating liquid 8 Microcapsule 21-1 to 21-3 Cell 22R Red color filter 22G Green color filter 22B Blue color filter 31 Projector 32 Screen 33 Information display panel 34 Frame 41, 43 Image 42, 44 one pixel 45 pixel area

Claims (3)

  Projector screen for projecting an image projected from a projector, wherein a display medium is sealed in a space between two substrates, at least one of which is transparent, and the display medium is moved to display information such as an image A projector screen comprising an information display panel capable of displaying the same image as the image projected by the projector.   The projector screen according to claim 1, comprising a plurality of information display panels.   The projector screen according to claim 1, wherein one pixel of an image projected from the projector is configured to match an integer multiple pixel of the information display panel.

Images