JP2009086531A - Pixel substrate, spatial light modulator and manufacturing method of pixel substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pixel substrate which has nanosized pixels and can respond to real-time driving, a spatial light modulator, and a manufacturing method of the pixel substrate. <P>SOLUTION: The spatial light modulator 10 comprises the pixel substrate 20; an ultraviolet laser 11 which outputs ultraviolet beam; a beam aperture 12 which forms the shape of the ultraviolet beam; and a mirror 13 which reflects the ultraviolet beam. The pixel substrate 20 includes a first transparent substrate 21 having translucency and a second transparent substrate 22 including a plurality of triangular pyramid-like projection parts 22a constituting the nanosized pixels, and the mirror 13 performs pixel selection scanning to each triangular pyramid-like projection part 22a with the ultraviolet beam at a response speed of several μs, whereby the pixel substrate responds to the real-time driving. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a pixel substrate, a spatial light modulator, and a method for manufacturing the pixel substrate that are used in, for example, a spatial image reproduction method for displaying a stereoscopic image.

  CRT (Cathode Ray Tube), LCD (Liquid Crystal Display), PDP (Plasma Display Panel), FED (Field Emission Display), etc. are commercially available as typical display elements for high-definition digital Hi-Vision receivers. In addition, various display methods such as organic EL have been researched and developed. When a CRT is enlarged, the volume and weight increase and it is difficult to introduce the CRT into a normal home. Therefore, flat displays such as LCDs and PDPs are mainly spreading for large screens.

  On the other hand, the stereoscopic video display method includes (1) a method based on parallax information, (2) a method based on depth information (depth sampling method), (3) a method based on luminance information (depth fusion method), and (4). There are aerial image reproduction methods. More specifically, in the method (1), the time division method (with glasses) and the space division method (with glasses, without), and in the method (4), there are integral photography, light beam reproduction method, holography method, etc. Has been developed. Most of the methods (1) to (3) have been put into practical use, but the method (4) is still in the research stage. Among these methods, the most natural three-dimensional image display method that hardly gives viewers eyestrain is the aerial image reproduction method (4).

  In this 3D television system based on the spatial image reproduction method, a spatial light modulator that has a spatial resolution about the wavelength of visible light and can be driven in real time is required as an indispensable device. Not developed. At present, research is being carried out by diverting flat displays such as LCD and PDP for high-definition video and input / output devices for super high-definition video.

  For example, LCD panels are used in real-time holography and integral photography (see, for example, Non-Patent Documents 1 and 2).

  Research on electrophoresis is also underway. For example, in a microcapsule type electrophoretic display, a pigment that is colored and charged positively or negatively is enclosed in a polymer microcapsule that encloses a liquid, and this is moved to the front substrate side or the back substrate side by an external electric field. A contrast as a reflective display is obtained (for example, see Non-Patent Document 3).

  In this type of system, there are a case where the colored particles are moved in the lateral direction within the substrate surface, a twisting ball type which rotates a sphere, or a toner type. In particular, an electro-powder fluid type in which fine particles made of a polymer are caused to fly in an electric field has been recently developed (for example, see Non-Patent Document 4).

  In addition, an electrolytic deposition method in which silver ions are deposited from an electrolyte on a transparent substrate by an applied voltage to reflect external light has been studied, and high reflectance characteristics are obtained at a low voltage. Further, as a method of applying a thermal coloring reaction, a display using a viologen coloring reaction has been prototyped (for example, see Non-Patent Document 5).

  On the other hand, in the mechanical external light modulation system, DMD (Digital Micro-mirror Device) has already been put on the market as a spatial light modulator manufactured by applying a semiconductor microfabrication technology called MEMS (Micro-Electro Mechanical Systems). (For example, refer nonpatent literature 6). This device produces a fine mirror array of a dozen micron squares corresponding to pixel dots, and modulates incident light with the tilt of the mirror for each pixel dot. In a similar manner, by applying a voltage between two small and thin metal face plates, an attractive force is generated between them to control the distance between the two, and the interference effect of incident light is used to make the light Spatial light modulators that control reflection and absorption of light have been developed (see Non-Patent Document 7, for example).

In addition, a magneto-optical spatial light modulator (MOSLM) using the Kerr effect has also been studied (for example, see Non-Patent Document 8).
T.A. Misina, M.M. Okui, and F.M. Okano, “Viewing-Zone Enhancing Method for Sampled Hologram what uses High-Order Diffraction”, Applied Optics, Vol. 41 (2002), p. 1489-1499 N. Hashimoto, K. et al. Kitamura, and S.K. Morokawa, “Real-time holography using high-resolution LCTV-SLM”, Proc. of SPIE 1461 (1991), pp. 291-302 B. Comiskey, J.A. D. Albert, H.M. Yoshizawa, and J.A. Jacobson, “An electrophoretic ink for all-printed reflective electrodisplays”, Nature Vol. 394 (1998) pp. 253-255 R. Hattori, S.H. Yamada, Y .; Masuda and N.M. Nihei and R.A. Sakurai, “Ultra Thin and Flexible Paper-like Display using QR-LPD Technology”, SID04 Digest (2004), pp. 136-139 H. Pettersson, T.W. Gruszecki, L. H. Johansson, A.D. Norberg, M.M. O. M.M. Edwards, and A.A. Hagfeldt, “Screen-printed electrochromic displays based in nanocrystal lines”, SID Digest of Technical Papers 123 (2002). J. et al. Grimmett, J.M. Huffman, “Advances in DLP Technology: The New 10.8 μm Pixel and Beyond”, Proc. Int. Display Worksshops / Asia Display '05 M.M. W. Miles, "A New Reflective FPD Technology Using Interferometric Modulation", Society for Information Display '97 Digest, Session 7.3. M.M. Inoue, P.M. Lim, T .; Imura, K .; Iwasaki, T .; Yamanaka, H .; Umezawa, and H.H. Horimai, "Development of Magneto-Optic Spatial Light Modulators and Their Application in Collinear Holography II", The Institute of Electronics, Information and Communication Engineers Technical Report MR2005-60 (2006-03), pp. 23-28 [in Japan]

  By the way, as described above, a stereoscopic television system based on the aerial image reproduction method is required to be driven in real time and to have a spatial resolution on the order of the wavelength of visible light. Specifically, since the wavelength of visible light is about 380 nm to 780 nm, a nano-sized pixel of about 200 nm to 800 nm square is required.

  However, the above-described conventional ones have problems in pixel size and response speed, and a three-dimensional television system based on the aerial image reproduction method cannot be realized.

  First, the pixel size will be described. As described above, the pixel size is determined by the structure and manufacturing technique in addition to the light modulation method or the display principle. For example, in the liquid crystal system, a TFT (Thin Film Transistor) for holding an image is required for each pixel dot. In order to ensure high contrast, the total liquid crystal thickness is required to be about 2 μm, and this liquid crystal layer must be sandwiched between two glass substrates or plastic substrates. Is said to be about 1 μm.

  Further, in the FED, for example, since there is a cell wall, it is difficult to produce a nano-sized pixel structure. In addition, the pixel size in the electrophoresis method is currently about several tens of μm square as the size of the microcapsule, and is about several tens of micron squares in the color reaction method. The mechanical external light modulation method is mainly determined by the accuracy of MEMS, but currently it has a pixel size of about 10 μm square for DMD and about 20 μm for optical interference type. It is difficult for the time being to extend the current technology.

  Next, regarding the response speed, for example, in a TN (Twisted Nematic) liquid crystal, it is typically about 10 ms due to the viscosity of liquid crystal molecules. Recently, researches on high-speed OCB (Optically Compensated Bend) liquid crystals that transition from a splay alignment state to a bend alignment state and turn on or off in the bend alignment state have become active, but the response speed is 3 ms. Degree. In the electrophoresis method, particles move or rotate by an electric field or a magnetic field, so that their response speed is only about several tens of ms. Note that the response speed in the mechanical external light modulation method is the smallest several μs, and this method enables real-time driving only in terms of response speed.

  On the other hand, the conventional flat display device performs pixel display by a matrix electric address method using cross wirings on the upper and lower sides of the panel. Therefore, if the matrix electrical addressing method is applied to a nano-sized pixel, a wiring with a small capacitance and resistance is essential, but there is a driving limit due to a time constant determined by the capacitance and resistance of the wiring. Realizing nano-sized pixels is difficult at present.

  The present invention has been made in view of the above-described circumstances, and provides a pixel substrate, a spatial light modulator, and a method for manufacturing the pixel substrate that have nano-sized pixels and can support real-time driving. Objective.

  The pixel substrate of the present invention includes a first transparent substrate and a second transparent substrate having a plurality of pyramidal projections, and a surface corresponding to the bottom surface of the pyramid shape is the surface of the first transparent substrate. One apex of the protrusion, the apex of the protrusion is located on a side different from the first transparent substrate with respect to the surface corresponding to the bottom of the pyramid, and on each side of the protrusion of the pyramid Each has a structure in which a phosphor is formed.

  With this configuration, the pixel substrate of the present invention has independent nano-sized pixels when the pyramidal projections are fabricated in nano-size, and light of a predetermined wavelength is provided on each side of the pyramid-shaped projections. Further, real-time driving can be supported by irradiating either one of the electron beam and the electron beam and performing pixel selective scanning.

  The pixel substrate of the present invention includes a first transparent substrate and a second transparent substrate having a plurality of pyramid-shaped depressions, and the vertex of the depression is one of the first transparent substrates. A surface facing the surface and corresponding to the bottom surface of the pyramid shape is located on a side different from the first transparent substrate with respect to the apex of the recess portion, and on each side surface of the pyramid recess portion, Each has a configuration in which a phosphor is formed.

  With this configuration, the pyramid-shaped depressions are produced in nano-size, so that they have independent nano-sized pixels, and either a light beam or an electron beam of a predetermined wavelength is provided on each side of the pyramid-shaped depressions. Can be applied to real-time driving.

  Furthermore, the pixel substrate of the present invention has a configuration in which a light-transmitting conductive film is provided between the first transparent substrate and the second transparent substrate.

  With this configuration, the pixel substrate of the present invention can release the charge generated inside the second transparent substrate to the outside when the hollow portion is irradiated with either a light beam or an electron beam having a predetermined wavelength.

  Furthermore, the pixel substrate of the present invention has a configuration in which the pyramid shape is one of a triangular pyramid and a quadrangular pyramid.

  With this configuration, the pixel substrate of the present invention can suitably deposit the phosphor on the side surface of the protrusion or the depression.

  Furthermore, the pixel substrate of the present invention has a configuration in which the phosphor includes a material that emits light by either a light beam having a predetermined wavelength or an electron beam.

  With this configuration, the pixel substrate of the present invention can emit nano-sized pixels to a desired color by using either a light beam having a predetermined wavelength or an electron beam.

  The spatial light modulator according to the present invention includes a pixel substrate, a beam generation unit that generates a light beam or an electron beam having a predetermined wavelength, and a beam irradiation unit that irradiates the pixel substrate with the beam. The irradiation unit has a configuration in which the phosphors on the respective side surfaces emit light in an irradiation state including a state in which the center of the beam is decentered from the apex of the pyramid shape.

  With this configuration, the spatial light modulator of the present invention can arbitrarily determine the chromaticity of each nano-sized pixel and cope with real-time driving of full-color display.

  In the spatial light modulator according to the present invention, the beam irradiation means includes a plurality of optical systems that individually emit the phosphors on the side surfaces.

  With this configuration, the spatial light modulator of the present invention can perform full-color display in real time with a plurality of optical systems.

  A method for manufacturing a pixel substrate according to the present invention is a method for manufacturing a pixel substrate, wherein a plurality of pyramidal protrusions are formed on a substrate having translucency by a process including X-ray lithography, electroforming, powder molding, and a nanoimprint process. And a step of depositing a phosphor material that emits light in a predetermined color by a beam of light having a predetermined wavelength or an electron beam on each of the side surfaces of the pyramidal protrusions by oblique vapor deposition. Have.

  With this configuration, the pixel substrate manufacturing method of the present invention can produce the pyramid-shaped projections with a nano-size, so that either a light beam or an electron beam with a predetermined wavelength is provided on each side surface of the pyramid-shaped projections. Can be provided, and a spatial light modulator that can be driven in real time can be provided.

  The pixel substrate manufacturing method of the present invention is a method for manufacturing a pixel substrate, the step of forming a plurality of pyramid-shaped depressions on a substrate having translucency by etching, and the step of forming the pyramid-shaped depressions. And a step of depositing a phosphor material that emits light of a predetermined color by a beam of light having a predetermined wavelength or an electron beam on each of the side surfaces by an oblique vapor deposition method.

  With this configuration, the method for manufacturing a pixel substrate according to the present invention can produce a pyramid-shaped depression with a nano-size, so that either a light beam or an electron beam having a predetermined wavelength is provided on each side surface of the pyramid-shaped depression. Can be provided, and a spatial light modulator that can be driven in real time can be provided.

  The present invention can provide a pixel substrate, a spatial light modulator, and a method for manufacturing the pixel substrate that have nano-sized pixels and can be driven in real time.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
First, the configuration of the spatial light modulator according to the first embodiment of the present invention will be described. FIG. 1A conceptually shows the configuration of the spatial light modulator 10 in the present embodiment. FIG. 1B is a plan view conceptually showing the pixel substrate 20 in the present embodiment.

  As shown in FIGS. 1A and 1B, the spatial light modulator 10 in this embodiment includes a pixel substrate 20, an ultraviolet laser 11 that outputs ultraviolet rays, and a beam aperture 12 that shapes the shape of the ultraviolet beam. And a mirror 13 for reflecting the ultraviolet beam. An ultraviolet light emitting diode may be used in place of the ultraviolet laser 11.

  The ultraviolet laser 11 generates laser light in the ultraviolet region, for example, ultraviolet semiconductor laser light using gallium nitride (GaN), and outputs the laser light to the beam aperture 12. The ultraviolet laser 11 corresponds to the beam generating means of the present invention.

  The beam aperture 12 shapes the shape of the ultraviolet beam output from the ultraviolet laser 11 and outputs it to the mirror 13.

  The mirror 13 reflects the ultraviolet beam from the beam aperture 12 toward the pixel substrate 20. A mirror scanning control unit (not shown) for selectively scanning pixels on the pixel substrate 20 is connected to the mirror 13. Further, the mirror 13 is manufactured by, for example, a semiconductor microfabrication technique called MEMS, and reflects the ultraviolet beam from the beam aperture 12 by the control operation of the mirror scanning control unit, and the pixel with a response speed of several μs. Selective scanning is possible. The mirror 13 corresponds to the beam irradiation means of the present invention.

  The pixel substrate 20 includes a first transparent substrate 21 and a second transparent substrate 22 having a plurality of triangular pyramidal protrusions. The second transparent substrate 22 has an array of triangular pyramidal projections on one side, and the other side is a flat surface.

  The first transparent substrate 21 is made of a material that transmits light in the visible light region, for example, a glass substrate. The second transparent substrate 22 is made of a visible light transparent material such as glass or polymer, and includes a plurality of triangular pyramidal protrusions 22a formed in a triangular pyramid shape as shown in the figure. The triangular pyramidal protrusion 22a is formed by using, for example, a LIGA (Lithographie Galvanoforming and Abforming) process and a nanoprint technique. This LIGA process is a technique in which X-ray lithography using synchrotron radiation, electroforming, and metal or ceramic material molding (powder molding) are combined. The shape of the triangular pyramidal protrusion 22a is an equilateral triangle as viewed from above, but is not limited to the regular triangular pyramid shape. For example, the triangular pyramidal protrusion 22a is considered in consideration of the phosphor material deposition step described later. By optimizing the height dimension, the configuration can be other than the regular triangular pyramid shape.

  Further, the surface corresponding to the bottom surface of the triangular pyramidal protrusion 22a is opposed to the surface of the first transparent substrate 21, and the apex of the triangular pyramidal protrusion 22a is formed on the mirror 13 side. The triangular pyramidal protrusion 22a has three side surfaces 22b, 22c and 22d. On these side surfaces 22b, 22c, and 22d, phosphors that emit red, green, and blue light by an ultraviolet beam are formed, respectively. As the phosphor material, for example, an ultraviolet-excited phosphor made of an oxide phosphor, a sulfide phosphor, an organic material, or the like can be used.

  In addition, one triangular pyramidal projection 22a constitutes one nano-sized pixel. The pixel size is determined by the length of one side of the bottom surface of the triangular pyramidal protrusion 22a and is, for example, about 200 nm to 800 nm. Therefore, for example, when displaying a high-definition television image having a pixel size of 500 nm and a pixel number of 1920 × 1080, a full-color image can be obtained with a display unit size of only about 1 mm × 0.5 mm.

  Here, the ultraviolet beam from the mirror 13 in the triangular pyramidal protrusion 22a will be described. FIG. 2 shows a triangular pyramidal protrusion 22a constituting one pixel. As shown in FIG. 2, the beam diameter of the ultraviolet beam irradiated from the mirror 13 (see FIG. 1) is within the projection plane in the beam irradiation direction of the three side surfaces 22b, 22c, 22d (for example, within the ABC region of FIG. 2). ) To be completely and maximum. With this configuration, the spatial light modulator 10 according to the present embodiment can display RGB colors independently of each other. Further, the mirror 13 is configured such that the chromaticity of each pixel is determined by decentering the beam center of the ultraviolet beam with respect to the apex of the triangular pyramidal protrusion 22a. Specifically, the chromaticity at the time of light emission of the triangular pyramidal protrusion 22a is adjusted by combining the irradiation area of the ultraviolet beam with respect to each of the three side surfaces 22b, 22c and 22d and the light emission characteristics of each phosphor material.

  As described above, the spatial light modulator 10 according to the present embodiment includes the triangular pyramidal protrusion 22a that constitutes a nano-sized pixel, and the mirror 13 reflects the ultraviolet beam from the beam aperture 12 so that each triangular shape is reflected. Since pixel selection scanning is performed at a response speed of several μs with respect to the conical protrusion 22a, real-time driving can be supported.

In the above-described configuration, a conductive film may be formed between the first transparent substrate 21 and the second transparent substrate 22. For example, a conductive film can be formed by depositing on the first transparent substrate 21 a transparent conductive metal oxide such as ITO (indium doped tin oxide), doped SnO ₂ , or ZnO. With this configuration, it is preferable that the charge generated in the triangular pyramidal protrusion 22a can be released to the outside by irradiating the triangular pyramidal protrusion 22a with an ultraviolet beam.

  In the above-described embodiment, the configuration is such that the ultraviolet beam is irradiated. However, for example, an electron beam may be irradiated instead of the ultraviolet ray. In this case, a phosphor that emits red, green, and blue light by an electron beam is used as the phosphor. Here, the number of electron beams is not limited to one, and a plurality of electron beams may be applied to each color phosphor.

  Next, a method for manufacturing the pixel substrate 20 in the present embodiment will be described.

  First, an X-ray resist film such as PMMA (Polymethylmethacrylate) is applied on a transparent substrate having conductivity. The thickness to be applied is determined according to the size (pixel size) of the triangular pyramidal protrusion 22a to be formed. For example, when the size of the bottom side of the triangular pyramidal projection 22a is about 500 nm, the thickness of the X-ray resist film is preferably about 500 nm.

  Subsequently, with respect to the PMMA film, as shown in FIG. 3A, three times of 120 degrees so that the distribution of the X-ray absorption amount in the thickness direction becomes the distribution shown in the AA section, the BB section, and the CC section, respectively. A symmetrical belt-shaped X-ray beam is irradiated.

  Here, in FIG. 3A, the direction of the AA section indicates the distribution in the thickness direction of the X-ray absorption amount in the longitudinal section of the PMMA film. Further, the direction of the BB cross section shows the distribution in the thickness direction of the X-ray absorption amount in the cross section rotated right by 60 ° with respect to the direction of the AA cross section. Furthermore, the direction of the CC cross section indicates the distribution in the thickness direction of the X-ray absorption amount in the cross section rotated 60 ° to the left with respect to the direction of the AA cross section. In each cross-sectional view, the direction from the bottom of the black triangle toward the apex corresponds to the direction in which the amount of X-ray absorption increases. As the X-ray used in this step, an appropriate energy, for example, an X-ray of about several keV is selected from synchrotron radiation, and the irradiation conditions are adjusted. For example, X-ray irradiation may be performed while moving the X-ray mask so that the distribution in the thickness direction of the X-ray absorption amount becomes the distribution shown in the AA cross section, the BB cross section, and the CC cross section, respectively.

  Further, the PMMA triangular pyramid projection array as shown in FIG. 3B is obtained by immersing the transparent substrate on which the PMMA film irradiated with X-rays as described above is formed in a developing solution.

  Next, a manufacturing method of a working mold used for the spatial light modulator by the nanoimprint process based on the PMMA triangular pyramidal projection array will be described with reference to FIG.

  First, a metal such as Ni or Ta is deposited in the space of the triangular pyramidal projection array by electroforming using the PMMA triangular pyramidal projection array shown in FIG. 4A (FIG. 4B).

  Then, PMMA is peeled off using a solvent or the like by a lift-off method to form a metal master mold (FIG. 4C). A prepolymer (Pre-Polymer) is poured into the gap using this metal master mold (FIG. 4D).

  Next, by irradiating the prepolymer with ultraviolet rays, ultraviolet polymerization is performed to cure (FIG. 4E). Finally, the metal master mold is peeled off to obtain a polymer working mold (FIG. 4F).

  Next, a method for depositing the phosphor material on the working mold is shown in FIG. As shown in FIGS. 5A to 5C, oblique evaporation is performed so that red, green, and blue phosphor materials are deposited on the side surfaces 22b, 22c, and 22d of the working mold, respectively. Here, an oblique deposition angle and other deposition conditions are obtained in advance so that the phosphor material is deposited only on each side surface. As the phosphor material, for example, an oxide phosphor, a sulfide phosphor, an organic material, or the like is used, and the film thickness is preferably about 100 nm. In particular, when an organic material is used, the film thickness can be made thinner than other phosphor materials, so that the pixel shape can be determined with high accuracy. In addition, by studying in advance the optimization of the oblique deposition angle of the phosphor material and the height of the triangular pyramidal projection 22a, the phosphors of each color can be deposited almost uniformly on each side by oblique deposition. preferable.

  As described above, according to the spatial light modulator 10 in the present embodiment, the plurality of triangular pyramidal protrusions 22a are respectively provided with the side surfaces 22b on which phosphors that emit red, green, and blue light are formed by ultraviolet beams. 22c and 22d constitute a nano-sized pixel, and the mirror 13 performs pixel selection scanning with a response speed of several μs for each triangular pyramidal protrusion 22a with respect to each of the triangular pyramidal projections 22a. be able to.

  In addition, according to the spatial light modulator 10 in the present embodiment, unlike the conventional pixel structure, the configuration including the plurality of triangular pyramidal protrusions 22a does not require a wall structure, and thus is higher than the conventional one. Pixel separation can be achieved with high precision. In addition, because it is configured to selectively scan pixels with an ultraviolet beam, it is an ultra-high resolution spatial light with ultra-high resolution and nano-pixel resolution exceeding the limit of electrical address determined by the resistance and capacitance of conventional wiring. A modulator can be obtained.

  Further, by using the spatial light modulator 10 in the present embodiment, it is possible to display a real image type stereoscopic image in real time. This can be, for example, a breakthrough for realizing highly realistic broadcasting on a stereoscopic television.

  In addition, the spatial light modulator 10 according to the present embodiment is mounted on, for example, eyeglasses, or applied to an ultra-compact and high-definition wearable display for one eye, thereby contributing to the spread and development of ubiquitous universal services. be able to.

  In addition, the spatial light modulator 10 in the present embodiment can be applied to a wearable display, for example, can assist medical operations and other device operations, or can be combined with a navigation system to It can also contribute to supporting activities for people with disabilities.

  In the above-described embodiment, the example in which the pixel is configured by the triangular pyramidal protrusion 22a has been described. However, the present invention is not limited to this, and the pixel may be configured by a quadrangular pyramidal protrusion. This quadrangular pyramidal protrusion is obtained, for example, by irradiating X-rays while moving the X-ray mask with respect to the AA cross-sectional direction in FIG. 3A and the direction orthogonal to this direction. In this case, it is preferable to optimize the height of the quadrangular pyramidal protrusions in consideration of oblique vapor deposition of the phosphor material. Further, as a phosphor material in the quadrangular pyramidal projection, for example, a cyan phosphor material can be used in addition to red, green, and blue on the four surfaces.

  In the above-described embodiment, the configuration in which pixel selection scanning is performed by one mirror 13 has been described as an example. However, the present invention is not limited to this, and for example, light is emitted in red, green, and blue. A configuration may be adopted in which full color display is performed using a total of three types of irradiation optical systems that perform pixel selective scanning by individually irradiating the phosphor material with an ultraviolet beam.

(Second Embodiment)
The spatial light modulator in the present embodiment is provided with a pixel substrate 30 as shown in FIG. 6 in place of the pixel substrate 20 of the spatial light modulator 10 (see FIG. 1) in the first embodiment. Therefore, the description which overlaps with the description of the spatial light modulator 10 in the first embodiment is omitted.

  As shown in FIGS. 6A and 6B, the pixel substrate 30 in the present embodiment includes a first transparent substrate 31 having a light transmitting property and a second transparent substrate 32 having a light transmitting property. I have.

  The 1st transparent substrate 31 is the structure equivalent to the 1st transparent substrate 21 in 1st Embodiment, and is comprised with the material which permeate | transmits the light of visible region, for example, a glass substrate.

  The second transparent substrate 32 is made of, for example, an etching material that transmits visible light, for example, a glass substrate, and has a plurality of triangular pyramid depressions that are formed in an equilateral triangle shape when viewed from above, as shown in the figure. 32a, and the other surface is a flat surface. The triangular pyramid depression 32a is produced by etching, for example, and has three side surfaces 32b, 32c, and 32d. On the side surfaces 32b, 32c, and 32d, phosphors that emit red, green, and blue light by ultraviolet rays are formed, respectively.

  Further, one triangular pyramid recess 32a constitutes one nano-sized pixel. The pixel size is determined by the length of one side of the bottom surface of the triangular pyramid depression 32a, and is preferably about 200 nm to 800 nm, for example. Further, the chromaticity of each pixel is determined by decentering the beam center of the ultraviolet beam with respect to the apex of the triangular pyramid depression 32a by the mirror 13 (see FIG. 1). Moreover, it is preferable to make the beam diameter of the ultraviolet beam irradiated from the mirror 13 smaller than the size of the surface corresponding to the bottom surface of the triangular pyramid depression 32a, as described in FIG.

  As described above, according to the spatial light modulator in the present embodiment, the plurality of triangular pyramid depressions 32a are respectively provided with the side surfaces 32b and 32c on which phosphors that emit red, green, and blue light are formed by ultraviolet rays. And 32d constitute a nano-sized pixel, and the mirror 13 performs pixel selection scanning with a response speed of several μs for each triangular pyramid depression 32a with respect to each of the triangular pyramid depressions 32a. Can do.

  In the above-described embodiment, the example in which the pixel is configured by the triangular pyramid depression 32a has been described. However, the present invention is not limited to this, and similarly to the description in the first embodiment, You may comprise a pixel by a pyramid hollow part.

  Further, similarly to the first embodiment, a conductive film may be formed between the first transparent substrate 31 and the second transparent substrate 32. With this configuration, it is preferable that the charge generated inside the second transparent substrate 32 can be released to the outside by irradiating the triangular pyramid depression 32a with an ultraviolet beam.

  As described above, the pixel substrate, the spatial light modulator, and the method for manufacturing the pixel substrate according to the present invention have the effect of having nano-sized pixels and being able to support real-time driving, and are It is useful as a pixel substrate and a spatial light modulator that can be used for a display that displays an image in real time, a display mounted on spectacles, an ultra-compact and high-definition wearable display, a manufacturing method of the pixel substrate, and the like.

The figure which shows notionally the structure in 1st Embodiment of the spatial light modulator which concerns on this invention (a) The figure which shows notionally the structure of the spatial light modulator in 1st Embodiment (b) 1st Conceptual plan view of a pixel substrate in the embodiment Explanatory drawing which shows the relationship between the triangular pyramid projection part which comprises 1 pixel, and a beam spot in 1st Embodiment of the spatial light modulator which concerns on this invention. FIG. 4 is an explanatory diagram of an X-ray irradiation process and a development process in the first embodiment of the spatial light modulator according to the present invention. (A) A diagram showing a distribution in the thickness direction of an X-ray absorption amount with respect to a PMMA film. Diagram showing rear triangular pyramidal projection array Explanatory drawing about the manufacturing method by the nanoimprint process of the working mold used for a spatial light modulator in 1st Embodiment of the spatial light modulator which concerns on this invention (a) Explanatory drawing of a triangular pyramidal projection array (b) Electroforming Explanatory drawing of process (c) Explanatory drawing of lift-off process (d) Explanatory drawing of process for pouring prepolymer (e) Explanatory drawing of ultraviolet irradiation process (f) Diagram showing a state in which a working mold of polymer is obtained Explanatory drawing of the deposition process of the phosphor material in 1st Embodiment of the spatial light modulator which concerns on this invention (a) Top view and EE sectional drawing of triangular pyramidal projection array (b) Plan view of triangular pyramidal projection array FF cross section (c) Plane view and GG cross section of triangular pyramidal projection array The figure which shows notionally the structure in 2nd Embodiment of the spatial light modulator which concerns on this invention.

Explanation of symbols

10 Spatial light modulator 11 Ultraviolet laser (beam generating means)
12 Beam aperture 13 Mirror (beam irradiation means)
20, 30 Pixel substrate 21, 31 First transparent substrate 22, 32 Second transparent substrate 22a Triangular pyramidal projections 22b, 22c, 22d Triangular pyramidal projection side surfaces 32a Triangular pyramidal depressions 32b, 32c, 32d Triangular pyramidal depressions Part side

Claims (9)

A first transparent substrate, and a second transparent substrate having a plurality of pyramidal projections,
The surface corresponding to the bottom surface of the pyramid shape faces one surface of the first transparent substrate, and the apex of the protrusion is the first transparent substrate with respect to the surface corresponding to the bottom surface of the pyramid shape. A pixel substrate, characterized in that a phosphor is formed on each side surface of the pyramidal protrusions, which are located on different sides. A first transparent substrate, and a second transparent substrate having a plurality of pyramidal depressions,
The apex of the recess portion faces one surface of the first transparent substrate, and the surface corresponding to the bottom surface of the pyramid shape is a side different from the first transparent substrate with respect to the apex of the recess portion. And a phosphor is formed on each side surface of the pyramidal depression. The pixel substrate according to claim 1, further comprising a light-transmitting conductive film between the first transparent substrate and the second transparent substrate. The pixel substrate according to any one of claims 1 to 3, wherein the pyramid shape is one of a triangular pyramid and a quadrangular pyramid. 5. The pixel substrate according to claim 1, wherein the phosphor includes a material that emits light by a beam of light having a predetermined wavelength or an electron beam. 6. 6. The pixel substrate according to claim 1, a beam generation unit that generates a beam of light or electrons having a predetermined wavelength, and a beam irradiation unit that irradiates the pixel substrate with the beam. Prepared,
The spatial light modulator, wherein the beam irradiation means causes the phosphors on the side surfaces to emit light in an irradiation state including a state in which a center of the beam is decentered from the apex of the pyramid shape. The spatial light modulator according to claim 6, wherein the beam irradiation unit includes a plurality of optical systems that individually emit the phosphors on the side surfaces. A method of manufacturing a pixel substrate according to any one of claims 1, 3 to 5,
A step of forming a plurality of pyramidal protrusions on a substrate having translucency by a process including X-ray lithography, electroforming, powder molding and a nanoimprint process; and a predetermined wavelength on each side surface of the pyramidal protrusions Depositing a phosphor material that emits light of a predetermined color by one of the light and electron beams by an oblique vapor deposition method. A method for manufacturing a pixel substrate according to any one of claims 2 to 5,
A step of forming a plurality of pyramid-shaped depressions on a light-transmitting substrate by etching, and light emission in a predetermined color by one of light and electron beams of a predetermined wavelength on each side surface of the pyramid-shaped depressions Depositing the phosphor material to be deposited by oblique vapor deposition.