JP2020160189A - Spatial light modulator and holography device - Google Patents

Abstract

To provide a magnetooptic spatial light modulator included in a single-plate system full-colour holography device capable of reproducing a bright and clear image with high frame rate.SOLUTION: A spatial light modulator 10 comprises: a first layer spatial light modulator 11 including magnetic fine lines 41 arranged side by side with a pitch p1y; a second layer spatial light modulator 12 including magnetic fine lines 42 arranged side by side with a pitch p2y; a third layer spatial light modulator 13 including magnetic fine lines 43 arranged side by side with a pitch p3y. The three light modulators are stack from top in this order, and respectively receive light LBi, LGi and LRi of center wavelengths λB, λG and λR simultaneously from top (p1y/λB=p2y/λG=p3y/λR). The third layer spatial light modulator 13 optically rotates the light LRi into light LRo with the magnetic fine line 43 and reflects it. The second layer spatial light modulator 12 optically rotates the light LGi into light LGo with the magnetic fine line 42, reflects it, and transmits therethrough the light LRi, LRo. The first layer spatial light modulator 11 optically rotates the light LBi into light LBo with the magnetic fine line 41, reflects it, and transmits therethrough the light LGi, LRi, LGo and LRo.SELECTED DRAWING: Figure 6

Description

The present invention relates to a spatial light modulator that spatially modulates the phase and amplitude of light by a magneto-optical effect and emits the incident light, and a holographic apparatus using this spatial optical modulator.

Spatial light modulators use optical elements (optical modulation elements) as pixels and arrange them two-dimensionally in a matrix to spatially modulate the phase and amplitude of light. Display technology and recording technology. It is widely used in such fields. One of them is an electron holography apparatus that reproduces a desired stereoscopic image by using a spatial light modulator for a hologram that records interference fringes. In an electron holography apparatus (hereinafter, holography apparatus), the larger the pixel (pitch) with respect to the wavelength of the reproduced light, the narrower the viewing range angle. Therefore, as the spatial optical modulator used, a DMD (Digital Micromirror Device) or a liquid crystal in which movable micromirror surfaces equipped with semiconductor elements are arranged in an array has been conventionally applied (for example, Patent Documents 1 to 1). 3) In recent years, it has become easier to further miniaturize pixels, and in order to reproduce stereoscopic images as moving images, the development of a magneto-optical spatial optical modulator using a magneto-optical material, which is expected to have high-speed processing potential. Is underway.

In a magneto-optical spatial light modulator, the Faraday effect (Kerr effect in the case of reflection) is used to change the direction of polarized light (optical rotation) when light incident on a magnetic material is transmitted or reflected. There is. That is, in the magneto-optical spatial light modulator (hereinafter, as appropriate, the spatial light modulator), the magnetization direction of the light modulation element provided with the magnetic film is changed for each pixel in a different direction, and the light modulation element in each magnetization direction is used. , It is modulated into light with different polarization directions, and the polarized light with a specific direction among the emitted light is extracted by a polarization filter. As a method of changing the magnetization direction of the light modulation element mounted on such a magneto-optical spatial light modulator, a magnetic field generated by a current supplied to the wiring provided around the light modulation element is applied to the light modulation element. A magnetic field application method (for example, Patent Document 4) or a spin injection magnetization reversal method (for example, Patent Document 5) in which spin is injected by supplying an electric current from a pair of electrodes (wiring) connected above and below the light modulation element. There is. Further, there is a domain wall moving type spatial light modulator (for example, Patent Document 6) which can be said to be a modification of the spin injection magnetization reversal method.

The magnetic wall movement type spatial light modulator described in Patent Document 6 is different from the spatial light modulator in which magnetic films (optical modulation elements) separated for each pixel are two-dimensionally arranged as described in Patent Documents 4 and 5. , Fine wire-shaped magnetic materials (magnetic thin wires) are arranged side by side to form an optical modulation element in which each of the magnetic fine wires is continuously arranged in a row. Magnetic domains with a width of about 300 nm or less are likely to be generated so as to divide them in the wire direction, and when both ends are connected to a power supply and a direct current is supplied, the magnetic domains are formed by the spin of electrons injected in the opposite direction. Since the domain walls that separate them move, all magnetic domains shift. In a domain wall moving type spatial optical modulator, all magnetic domains generated in a desired magnetization direction near one end of a magnetic wire are moved to a predetermined pixel position by a current supply and arranged in a row on the magnetic wire. Set each of the pixels in the desired magnetization direction. Therefore, unlike the magneto-optical spatial light modulators described in Patent Documents 4 and 5, it is not necessary to provide wiring for each pixel, and there is no gap between the light modulation elements in the thin line direction of the magnetic thin wire. , The aperture ratio of the pixel (the effective region for modulating the light) can be made particularly high.

These magneto-optical spatial light modulators display the light and darkness of monochromatic light. Therefore, a color holography apparatus using a spatial light modulator, particularly a magneto-optical spatial light modulator, is a dedicated spatial light modulator for each laser beam of each color of red (R), green (G), and blue (B). (For example, Patent Document 1), which combines the light emitted from each of these three spatial light modulators into one, or the time of one frame is divided into three to generate laser light of each color. Full color by a time division method (for example, Patent Documents 2 and 3) in which light and darkness of pixels of this spatial light modulator is alternately switched between red, green, and blue by alternately incident on one spatial light modulator. The display is realized.

Japanese Patent No. 4963477 Japanese Patent No. 581570 Japanese Unexamined Patent Publication No. 2012-242513 JP-A-2009-115916 Japanese Patent No. 5054636 Japanese Patent No. 5782334

In the three-panel holography apparatus described in Patent Document 1, three spatial light modulators individually inject laser light of each color and superimpose the emitted light of each of the three spatial light modulators. Since the vessels are arranged apart from each other and a large number of optical systems such as reflectors are provided, the structure becomes complicated and the size becomes large. In the time-division holography apparatus described in Patent Documents 2 and 3, the reproduced image becomes dark with a small amount of light due to time division, and unexpected changes in color tone, blurring, etc. are likely to occur. Further, it is difficult to increase the frame rate of a time-division holography apparatus, even if it is a spatial light modulator of a spin injection magnetization reversal system having a high-speed response.

The present invention has been made in view of the above problems, and is a magneto-optical effect capable of reproducing a bright and clear image, easily increasing the frame rate, and configuring a full-color holography apparatus that does not increase in size. An object of the present invention is to provide a single-plate type full-color spatial light modulator.

Among the magneto-optical spatial light modulators described in Patent Documents 4 to 6, the present inventors have a magnetic wall movement method that makes it particularly easy to miniaturize pixels and does not require wiring (electrodes) for each pixel. By applying a spatial light modulator, we came up with the idea of selectively reflecting and transmitting light by color (wavelength range) to this spatial light modulator.

The spatial optical modulator according to the present invention is provided with a plurality of pixel arrays in which light in a plurality of wavelength ranges is used as incident light and pixels are two-dimensionally arranged in the x direction and the y direction in the incident direction of the incident light. The polarization direction of the optical rotation is changed to a binary angle for each wavelength range, and the light is reflected and emitted. In each of the pixel arrays, magnetic wires extending in the x direction are arranged side by side to form the magnetic wires. Pixels arranged in a row in the direction of the thin line are partitioned in each of the above, and light in a unique wavelength range different from each other in the incident light is rotated by the magnetic thin line and reflected. The spatial light modulator is characterized in that each of the pixel arrays has the magnetic fine wires arranged side by side at a pitch that is a constant multiple of the central wavelength of the unique wavelength region. Alternatively, in the spatial optical modulator, in each of the pixel arrays, the x-direction length of the pixel is a constant multiple of the center wavelength of the unique wavelength region, and the magnetic wire is further arranged in the wire direction of each of the pixels. It is characterized in that it is divided into two and rotates in a predetermined one of the binary angles in one region on the same side thereof.

With this configuration, the spatial optical modulator includes a pixel array in which the pixels arranged in a row are composed of magnetic fine wires, so that the pixels can be easily miniaturized, and there is no wiring for each pixel, so that there is no wiring for each pixel, and there are a plurality of wavelength ranges. Pixel arrays that individually photomodulate light can be arranged one on top of the other, resulting in a compact size. In addition, since each pixel array has a pixel pitch corresponding to the wavelength of light, the viewing range angles of the emitted light are uniform. It becomes a thing.

In the holography apparatus according to the present invention, the space light modulator, the magnetization means for which the magnetic thin wire of the pixel array is set as one of the pixels and has a binary magnetization direction, and the magnetic thin wire is generated into the magnetic thin wire. A current supply means for supplying a pulsed current that moves a magnetic zone in a thin line direction, a multi-wavelength light source that irradiates the spatial optical modulator with light in a plurality of wavelength regions, and light emitted from the spatial optical modulator are incident. It includes a polarizing filter.

With such a configuration, the holography apparatus can simultaneously inject light in a plurality of wavelength ranges into the spatial light modulator at the same time, and the emitted light has substantially the same optical path, so that the structure is not complicated and the size is not increased. ..

According to the spatial light modulator according to the present invention, a compact holographic apparatus capable of displaying a bright and clear full-color image at a high frame rate with a wide viewing angle can be obtained. According to the holography apparatus according to the present invention, a bright and clear full-color image can be displayed at a high frame rate with a wide viewing angle.

It is a schematic diagram explaining the structure of the spatial light modulator which concerns on this invention. It is a perspective sectional view schematically explaining the structure of the spatial light modulator according to the 1st Embodiment of this invention. It is a side view seen from the Y direction of the spatial light modulator shown in FIG. It is external drawing of the element array for schematically explaining the operation of the magnetic wire of the spatial light modulator which concerns on this invention. It is a schematic diagram explaining the structure of the holography apparatus which concerns on this invention. It is a partial cross-sectional view on the YZ plane for schematically explaining the optical path in the spatial light modulator according to 1st Embodiment of this invention. It is sectional drawing in the YZ plane of the pixel array for schematically explaining the light modulation operation by the spatial light modulator and the reproduction of a stereoscopic image which concerns on 1st Embodiment of this invention. It is a partially cutaway perspective sectional view schematically explaining the structure of the monochromatic spatial light modulator constituting the spatial light modulator according to the modification of the 1st Embodiment of this invention. It is a perspective sectional view schematically explaining the structure of the spatial light modulator according to the 2nd Embodiment of this invention. It is a side view seen from the Y direction of the spatial light modulator shown in FIG. It is a partial cross-sectional view on the YZ plane for schematically explaining the optical path in the spatial light modulator according to the 2nd Embodiment of this invention. It is sectional drawing in the XZ plane of the pixel array for schematically explaining the light modulation operation by the spatial light modulator and the reproduction of a stereoscopic image which concerns on 2nd Embodiment of this invention.

A mode for carrying out the spatial light modulator and the holographic apparatus according to the present invention will be described with reference to the drawings. In order to clarify the explanation, the spatial light modulator and its elements shown in the drawings may be exaggerated in size and positional relationship, or the shape may be simplified, and a plurality of spatial light modulators are provided. The number of elements may be reduced.

[Spatial light modulator]
The spatial light modulator according to the present invention is a reflection type spatial light modulator in which light is incident on one surface and reflected to emit light from the same surface, and the polarization direction of the incident light is binary for each pixel. The light is emitted by changing the angle (optical rotation). Pixels refer to means for displaying information (bright / dark) in the smallest unit of display by a spatial light modulator. Further, the spatial light modulator according to the present invention emits light that is incident on light in a plurality of wavelength ranges and is rotated in each wavelength range. Such a spatial light modulator is used as a display device of a holographic apparatus, as will be described later, and enables the display of a full-color stereoscopic image. Hereinafter, embodiments of the spatial light modulator according to the present invention will be described in detail.

[First Embodiment]
Spatial light modulator 10 according to the first embodiment of the present invention, as shown in FIG. 1, in order from the side which enters the light L _W i, the first layer spatial light modulator 11, a second layer spatial light modulator The vessels 12 and the third layer spatial light modulators 13 (collectively, monochromatic spatial light modulators 11, 12, 13) are stacked and provided. Each of the monochromatic space optical modulators 11, 12, and 13 has a pixel array in which pixels are two-dimensionally arranged in the horizontal (H) direction and the vertical (V) direction, and the area provided with the pixel array is a pixel area. It is called IA1, IA2, IA3. The spatial light modulator 10 can reproduce a high-definition image as the number of pixels of the monochromatic spatial light modulators 11, 12, and 13 increases. As an example, each pixel is 1920 (H) × 1080 (V). Arrange.

The incident light L _W i is the three different wavelength ranges of light L _B i, L _G i, include L _R i, the light L _B i that is incident on the spatial light modulator 10 is reflected by, the polarization direction of the pixel become light L _B o has changed in two ways to exit each. Similarly, the light L _G i, L _R i incident on the spatial light modulator 10, respectively light L _G o, is emitted as L _R o. In the present specification and drawings, the light L _B i and the light L _B o, referred to as light L _B in such a case that does not identify the orientation (polarization component) of the polarization. Similarly, referred respectively light L _G i and the light L _G o light L _G, light L _R i and the light L _R o light L _R, and. Further, the incident light L _B i, L _G i, and L _R i are referred to as incident light Li when the wavelength is not specified. Similarly, the outgoing light L _B o, referred to as L _G o, L _R o outgoing light Lo.

Light L _B, L _G, L _R is the wavelength in this order is short, also intended to respective wavelength regions do not overlap each other. Here, the light L _B is the central wavelength lambda _B = 408 nm of the blue light, the light L _G is the center wavelength lambda _G = green light 530 nm, the light L _R is the red light having a center wavelength lambda _R = 708 nm. In the present application, the center wavelength may be a value included in the wavelength range, and is preferably the wavelength (peak wavelength) having the largest amount of light.

Monochromatic spatial light modulator 11, 12 and 13, respectively, is a monochromatic light L _B, L _G, the spatial light modulator of L _R. The first layer spatial light modulator 11 provided in the uppermost layer of the spatial light modulator 10, in the pixel region IA1, light was rotated the direction of polarization of the light L _B i that is incident on the angle of the predetermined binary L _It is modulated to Bo and reflected. The second layer spatial light modulator 12 provided between the first layer spatial light modulator 11 and the third layer spatial light modulator 13, in the pixel region IA2, the direction of polarization of the light L _G i incident modulated to reflect a predetermined binary optical rotated to an angle L _G o. Third layer spatial light modulator 13 provided in the lowermost layer of the spatial light modulator 10, in the pixel region IA3, light was rotated the direction of polarization of the light L _R i incident on the angle of the predetermined binary L _It is modulated to Ro and reflected. Further, the first layer spatial light modulator 11 is light L _G, not and not modulated by transmit L _R, a second layer spatial light modulator 12 and not modulated by transmitted light L _R. In the spatial light modulator 10, under the third layer spatial light modulator 13 provided (light L _W i from the side far side to be incident) on is a relatively deep penetration easy long wavelength in medium light by a structure for modulating the L _R, the light L _B, L _G, the attenuation of L _R is suppressed. Hereinafter, each element of the monochromatic spatial light modulators 11, 12, and 13 will be described.

As shown in FIGS. 2 and 3, the first layer spatial light modulator 11 is provided for each of the magnetic thin wires 41 and the magnetic thin wires 41 extending in the X direction arranged side by side on the substrate 61 and the substrate 61 at a pitch p1 _y. An electrode 51n connected to both ends, an electrode 51p (collectively, the electrode 51), and an insulating layer 64 that fills the space between the magnetic thin wires 41 and 41 are provided. The second layer space optical modulator 12 includes a substrate 62, a magnetic thin wire 42 extending in the X direction arranged side by side on the substrate 62 at a pitch p2 _y , and an electrode 52n and an electrode 52p connected to both ends of each magnetic thin wire 42 ( An electrode 52) and an insulating layer 64 that fills the space between the magnetic thin wires 42 and 42 are provided, not shown, but collectively as appropriate. The third layer space optical modulator 13 includes a substrate 63, a magnetic thin wire 43 extending in the X direction arranged side by side on the substrate 63 at a pitch p3 _y , and electrodes 53n and electrodes 53p (each of the magnetic thin wires 43 connected to both ends thereof) An electrode 53) and an insulating layer 64 that fills the space between the magnetic thin wires 43 and 43 are provided, not shown, but collectively as appropriate. The monochromatic spatial light modulators 11, 12, and 13 include the same number of magnetic fine wires 41, 42, and 43 as the number of pixels in the Y direction of the pixel array. For example, when designing the number of pixels in the Y direction to 1920, each 1920 Prepare this book. In FIG. 2, for the sake of brevity, a configuration is illustrated in which 16 magnetic thin wires 41, 42, and 43 are provided. Further, in FIGS. 2 and 3, the insulating layer 64 is transparent, and only the outline is represented by a broken line.

In the spatial light modulator 10, the X and Y directions are the pixel arrangement directions, and when used as a display device, one is the horizontal (H) direction and the other is the vertical (V) direction (see FIG. 1). In the present embodiment, it is preferable that the X direction, that is, the thin wire direction of the magnetic fine wires 41, 42, 43 is the vertical direction. Further, the Z direction (vertical direction), which is the stacking direction of the monochromatic spatial light modulators 11, 12, and 13, is the depth (D) direction. Incidentally, illustrating the side to be incident light L _W i as above.

The monochromatic spatial light modulators 11, 12, and 13 have substantially the same structure except for the dimensions in a plane (pointing to the XY plane) view, and are referred to as a monochromatic spatial light modulator 1 when not specified. The magnetic thin wires 41, 42, and 43 provided in the monochromatic spatial light modulator 1 are referred to as magnetic thin wires 4, and the widths W1, W2, and W3 are W, and the pitch, that is, the lengths of the pixels in the Y direction p1 _y , p2 _y. , P3 _y are referred to as p _y , and the pixel X-direction lengths p1 _x , p2 _x , and p3 _x are referred to as p _x . Similarly, the electrodes 51n, 52n and 53n are referred to as electrodes 5n, the electrodes 51p, 52p and 53p are referred to as electrodes 5p, the substrates 61, 62 and 63 are referred to as substrates 6, and the pixel regions IA1, IA2 and IA3 are referred to as pixel regions IA, respectively.

As shown in FIGS. 2, 3, and 4, the magnetic thin wire 4 (41, 42, 43) is a magnetic material formed in a straight line along the X direction, and the magnetic domain is divided in the thin line direction. By generating, one of them constitutes a plurality of pixels (optical modulation elements) arranged in a row in the X direction of the pixel array. For example, when the number of pixels in the X direction is 1080, each of the magnetic thin wires 41, 42, and 43 includes 1080 pixels continuously in the thin wire direction. In FIG. 4, for the sake of brevity, only the magnetic thin wire 4 and the electrodes 5n and 5p are shown for the monochromatic spatial light modulator 1. Further, in FIGS. 3 and 4, the arrows attached in the magnetic thin lines 4 (41, 42, 43) indicate the magnetization direction, and the magnetic domains having different magnetization directions are indicated by the presence or absence of shading. The magnetic thin wire 4 includes a region constituting the plurality of pixels (referred to as a pixel row), a writing region 4w (41w, 42w, 43w) on the side connected to the electrode 5n outside the pixel row, and electrodes at both ends. It has a region connected to 5n and 5p. The writing area 4w is a magnetic domain having a minimum length l _c or more of the magnetic domain in the thin line direction (X direction), and is aligned in the X direction in the monochromatic spatial light modulator 1 as shown in FIG. Provided. Minimum length l _c is the unit length of the writing, is set in the X-direction length p _x of the pixel (l _c = p _x).

The magnetic thin wire 4 is designed so that the width W is at least half the wavelength λ / 2 of the light so that the light in the wavelength range modulated by the monochromatic space optical modulator 1 exhibits a magneto-optical effect. On the other hand, the magnetic thin wire 4 preferably has a thickness (film thickness) of about 70 nm or less and a width W of about 300 nm or less so that magnetic domains can be easily divided only in the thin wire direction. Further, it is preferable that the width W of the magnetic thin wire 4 is not too large with respect to the minimum length l _c of the magnetic domain, that is, the pixel length p _x , so that the magnetic domain can be easily divided only in the thin wire direction. W is preferably 2p _x or less, and more preferably _px or less. However, even if the dimensions are not such, the magnetic domain can be set in the magnetic domain divided only in the wire direction by applying an external magnetic field in advance. Further, it is preferable that the adjacent magnetic thin wires 4 and 4 have a gap to the extent that they are not easily affected by the magnetization of each other. As further described below, the width W and the pitch p _y of the magnetic nanowire 4 (41, 42, 43) are monochromatic spatial light modulator 11, 12, 13 are designed to a unique value. Further, the magnetic thin wire 4 preferably has a thickness of 4 nm or more, although it depends on the material, in order to increase the optical rotation angle (car rotation angle) and reflect the magnetic wire 4. On the other hand, the magnetic thin wires 41 and 42 of the first and second layer spatial light modulators 11 and 12 have a thickness of 30 nm or less so as to easily transmit light in a part of the wavelength range as described later. More preferably, it is 20 nm or less.

A known ferromagnetic material can be applied to the magnetic thin wire 4, and it is preferably a material having a perpendicular magnetic anisotropy, and more preferably a material having a high magneto-optical effect (Kerr effect). Examples of such materials include a multilayer film in which a transition metal such as a Co / Pd multilayer film and Pd, Pt, and Cu are repeatedly laminated, and a rare earth metal and a transition metal such as Tb-Fe-Co and Gd-Fe. Examples thereof include an alloy with (RE-TM alloy) or a multilayer film such as a Tb / Co multilayer film. The magnetic thin wire 4 further has a protective film on the uppermost layer for preventing oxidation of the ferromagnetic material and a base film for ensuring adhesion on the lowermost layer, such as Ru, Ta, Cu, Pt, Au, and W. It may be provided with a non-magnetic metal film having a thickness of 1 to 10 nm (not shown). Alternatively, the magnetic thin wire 4 may be provided with an insulating film that transmits light such as MgO, SiO ₂ , Si ₃ N _4, etc. as the protective film or the base film, but is removed at the interface connected to the electrodes 5n and 5p. To. The magnetic thin wire 4 is formed into a fine wire shape by continuously forming these materials by a known method such as a sputtering method and using photolithography, etching, lift-off, chemical mechanical polishing (CMP) method, damascene method or the like. Being done.

In the writing region 4w, the magnetic thin wire 4 has a structure corresponding to the magnetization method (writing method) in order to change (magnetize) in a desired magnetization direction by the magnetization means 8 only in this region. Specifically, as shown in FIG. 4, the lower side of the magnetic thin wire 4 (opposing the magnetizing means 8) so that the magnetic field MF is vertically applied from the magnetic head of the magnetizing means 8 facing the writing region 4w. A laminated structure in which a soft magnetic layer is provided via a non-magnetic layer on the side opposite to the side to be magnetized (see Patent Document 6).

Further, the magnetic wire 41, the light L _B in a wavelength region in which the first layer spatial light modulator 11 modulates, it is preferable high reflectivity and magneto-optical effect, also, in the long wavelength range than the light L _B light L _G, it is preferred high transmittance for L _R, selecting such optical characteristics are such a material and thickness obtained. Similarly, the magnetic wire 42 is preferably a high reflectivity and magneto-optical effect for light L _G in a wavelength range the second layer spatial light modulator 12 modulates, also, in the long wavelength range than the light L _G light preferably it has high transmittance for L _R. The magnetic wire 43 preferably has a high reflectivity and magneto-optical effect for light L _R in a wavelength range third layer spatial light modulator 13 modulates. The reflectance and transmittance of the magnetic thin wires 41, 42, and 43 can be controlled not only by the material of the magnetic material alone or the thickness, but also by, for example, the material of the base film. The Kerr rotation angle of the light L _B by the magnetic wire 41 θk1, θk2 the Kerr rotation angle of the light L _G by the magnetic wire 42, the Kerr rotation angle of the light L _R according to the magnetic wire 43 represents a θk3, θk1, θk2, the Shitakei3 When either is not specified, it is called a car rotation angle θk.

The electrodes 5n and 5p are connected to one end and the other end as terminals of the magnetic thin wire 4 in order to supply a current from an external power source (pulse current source 7) to the magnetic thin wire 4 in the thin wire direction. The electrode 5n is connected to the negative electrode of the pulse current source 7, and the electrode 5p is connected to the positive electrode. In FIG. 4, the electrodes 5n and 5p are connected to the upper surface near both ends of the magnetic thin wire 4, but the present invention is not limited to this, and the electrodes 5n and 5p may be connected to, for example, the lower surface. The electrodes 5n and 5p are formed of a metal such as Cu, Al, Au, Ag, Ta, Cr, Co or a general metal electrode material such as an alloy thereof. The electrodes 51, 52, and 53 do not have to have the same material and dimensions, and can be designed according to the width W and the like of the magnetic thin wires 41, 42, and 43 to be connected.

The substrate 6 is a base for forming the magnetic thin wire 4. A known substrate material can be applied to the substrate 6, and a material having a low light reflectance is preferable, and for the substrates 61 and 62, a material having a higher light transmittance is preferable. Specifically, SiO ₂ (silicon oxide, glass), MgO (magnesium oxide), sapphire, GGG (gadolinium gallium garnet), SiC (silicon carbide), Ge (germanium) single crystal substrate, various transparent plastic substrates, etc. Can be mentioned. The substrates 61, 62, and 63 do not have to have the same material and thickness. Specifically, since the lowermost substrate 63 does not have to transmit light, the magnetic thin wires 41 and 42 and the magnetic thin wires 42 have a sufficient thickness to support the entire spatial light modulator 10 flatly. The substrates 61 and 62 provided between the layers between the and 43 can be thinned so as to sufficiently transmit light. Further, the substrate 61 may have a high transmittance of light L _G and L _R , and the substrate 62 may have a high transmittance of light L _R.

The insulating layer 64 is provided on the substrate 6 together with the magnetic thin wires 4 to insulate between the adjacent magnetic thin wires 4 and 4 and protect the side surfaces and the upper surface of the magnetic fine wires 4. In FIGS. 2 and 3, the insulating layer 64 is provided to have the total thickness of the magnetic thin wire 4 and the electrodes 5n and 5p connected to the magnetic thin wire 4, and exposes the upper surface of the electrodes 5n and 5p. In the writing area 4w, it is preferable to design the thickness of the insulating layer 64 so that the distance between the magnetic wire 4 and the magnetic head of the magnetizing means 8 is in an appropriate range according to the writing method. .. Insulating layer 64, a known inorganic insulating material can be applied, further light _{(L B, L G, L R} ) is preferably high transmittance material, specifically, such as SiO _2, Al ₂ O ₃ Examples thereof include an oxide film, Si ₃ N ₄ and Mg F ₂ . Further, the insulating layer 64 preferably has a refractive index equal to or close to that of the substrate 6. By selecting such a material, the light L _B traveling between adjacent magnetic wire 4, 4, L _G, L _R is hardly reflected by the interface between the insulating layer 64 and the substrate 6, it is not optically modulated light Li is Suppresses being emitted. Further, between the magnetic thin wires 4 and 4, the magnetic fine wires 4 may be embedded in parallel linear grooves formed by processing the substrate 6 so that the substrate 6 is provided instead of the insulating layer 64. .. Like the substrate 6, the insulating layer 64 does not have to have the same material and thickness in the monochromatic spatial light modulators 11, 12, and 13. For example, the insulating layer 64 of the second layer spatial light modulator 12 may be higher the transmittance of light L _G, L _R, the insulating layer 64 of the third layer spatial light modulator 13 has the transmittance of light L _R high Just do it.

As shown in FIG. 3, the spatial light modulator 10 has a longer X-direction length in the order of the first layer spatial light modulator 11, the second layer spatial light modulator 12, and the third layer spatial light modulator 13. It is designed and both ends in the X direction are formed in a stepped shape. That is, the second and third layer spatial light modulators 12 and 13 are outward in the X direction with respect to the pixel regions IA2 and IA3 as compared with the upper layer first and second layer spatial light modulators 11 and 12. It overhangs and is formed large. Due to such a structure, the spatial light modulator 10 includes not only the electrodes 51 connected to both ends of the magnetic thin wires 41 of the first layer spatial light modulator 11 on the uppermost layer, but also the second layer spatial light modulator below the electrodes 51. The electrodes 52 of 12 and the electrodes 53 of the third layer spatial light modulator 13 are exposed on the upper surface and can be connected to an external power source (pulse current source 7). Further, the writing area 42w of the magnetic thin wire 42 and the writing area 43w of the magnetic thin wire 43 are also arranged on the outer sides of the first and second layer spatial light modulators 11 and 12 (boards 61 and 62) in the X direction. Since only the insulating layer 64 is provided on the upper surface, the magnetic field can be applied by facing the external magnetization means 8 as well. Further, the first layer spatial light modulator 11 includes optical L _G i, L _G o and optical L _R i that enter and exit the pixel regions IA2 and IA3 of the lower second and third layer spatial light modulators 12 and 13. , so as not to block the L _R o magnetization means 8 and electrode 51, designing the position and length of the magnetic wire 41 of the write region 41w. Similarly, a second layer spatial light modulator 12, light L _R i for incident and exit to the pixel region IA3 of the third layer spatial light modulator 13, so as not to block the L _R o, the position of the write region 42w and Design the length of the magnetic wire 42.

Further, as will be described later, the magnetic thin wires 41, 42, and 43 are arranged side by side so that the ratios of the pitches p1 _y , p2 _y , p3 _y and the wavelengths λ _B , λ _G , and λ _R are equal. Therefore, the pitch becomes longer in the order of p1 _y , p2 _y , and p3 _y , that is, the length in the Y direction becomes longer in the order of the pixel regions IA1, IA2, and IA3. However, the substrates 61, 62, and 63 are formed in the same Y-direction length in accordance with the longest pixel region IA3. Further, as the outgoing light L _B o from pixel regions _{IA1, IA2, IA3, L G} o, each center of L _R o match, first, second, third layer spatial light modulator 11 and 12, 13 are preferably arranged and laminated, and here, they are arranged so that the centers of the pixel regions IA1, IA2, and IA3 coincide with each other in a plan view. Therefore, in the first and second layer spatial light modulators 11 and 12, magnetic thin wires 41 and 42 are not provided near both ends (both edges) in the Y direction, and only the insulating layer 64 is provided on the substrates 61 and 62. ..

Next, the pixel sizes of the first, second, and third layer spatial light modulators 11, 12, and 13 will be described in detail. As described above, the spatial light modulator 10 is a display device of the holographic apparatus. Therefore, the first layer spatial light modulator 11, the light L _B i that enters the magnetic wire 41 is optical rotation in accordance with the magnetization direction, as reflected outgoing light L _B o is the diffracted light, magnetic wire pitch p1 _y and the width W1 of 41, the following equation based on the central wavelength lambda _B of the light L _B (1), is designed in the range of (2). Similarly, a second layer spatial light modulator 12, the pitch p2 _y and the width W2 of the magnetic wire 42, the following equation based on the central wavelength lambda _G of the light L _G (3), is designed in the range of (4) To. Then, the third layer spatial light modulator 13 is designed so that the pitch p3 _y and the width W3 of the magnetic thin wire 43 are within the ranges of the following equations (5) and (6) based on the central wavelength λ _R of the optical L _R. ..
λ _B / 2 ≦ W1 <λ _B ... (1)
p1 _y −W1 ≧ λ _B / 2 ・ ・ ・ (2)
λ _G / 2 ≦ W2 <λ _G ... (3)
p2 _y −W2 ≧ λ _G / 2 ・ ・ ・ (4)
λ _R / 2 ≦ W3 <λ _R ... (5)
p3 _y −W3 ≧ λ _R / 2 ・ ・ ・ (6)

Further, the width W1 of the magnetic thin wire 41 is W1 <λ _G / 2 so that it is difficult for the first layer spatial light modulator 11 to give an optical action when the light L _G , _LR is transmitted. It is preferable that W1 <λ _Gmin / 2 is more preferable. Similarly, the width W2 of the magnetic thin wire 42 is preferably W2 <λ _R / 2 so that the second layer spatial light modulator 12 does not easily give an optical action when transmitted through the light L _R. More preferably, W2 <λ _Rmin / 2. minimum wavelength of lambda _Gmin light _{L G (≦ λ G),} λ Rmin is the minimum wavelength of the light L _R (≦ λ _R), however, no substantial influence on the reproduced image, the light L _G, L Wavelength regions with low relative intensity in each of _R shall be excluded. This structure of the spatial light modulator 10, light L _G, L _R is an insulating layer 64 and the magnetic wire 41 arranged alternately in the Y direction of the first layer spatial light modulator 11, an insulating layer 64 Since it is magneto-optically transmitted as an integral medium, it is not rotated by the magnetic thin wire 41. Similarly, the light L _R is the magnetic wire 42 and the insulating layer 64 disposed alternately in the Y direction of the second layer spatial light modulator 12, since the transmission magnetically optically as an intermediary for the integral formed of an insulating layer 64 , The magnetic thin wire 42 does not rotate.

Here, in a holography apparatus using a spatial light modulator having a pixel length p, the diffraction angle φ of light having a wavelength λ emitted from a pixel is represented by the following equation (7). In the spatial light modulator 10, a monochromatic spatial light modulator 11, 12, 13, each of the outgoing light L _B o, L _G o, so L diffraction angle _R o phi matches the length Y direction of the pixel i.e. pitch p1 _y, p2 _y, p3 _y of the magnetic wire 41, 42, 43, each of the modulated light L _B, L _G, L the center wavelength of _{R λ B, λ G,} a matching ratio lambda _R (lower Equation (8)). With such a configuration, details as described later, the light only valid outgoing light L _B o reflected monochromatic spatial light modulator 11, 12, 13 assigned to each, L _G o, as L _R o , A stereoscopic image can be formed. Therefore, the incident light L _B i, L _G i, and L _R i can be incident on the spatial light modulator 10 as an integrated white light L _Wi . Further, in the holography apparatus, when the pixel length p is a multiple of a half wavelength of the wavelength λ, the emitted lights of each pixel interfere with each other particularly strongly. Therefore, monochromatic spatial light modulator 11, 12, light L _B, L _G, the half wavelength of L _R λ _B / 2 pixels in the Y-direction length p1 _y, p2 _y, p3 _y is the respective modulation, lambda It is preferably a multiple of _G / 2, λ _R / 2.
φ = sin ^-1 (λ / 2p) ・ ・ ・ (7)
p1 _y / λ _B = p2 _y / λ _G = p3 _y / λ _R ... (8)

Further, as represented by the following equation (9), the viewing angle Ψ of the light having the wavelength λ in the holography apparatus is twice the diffraction angle φ (Ψ = 2φ), and the pixel length p is small (short). As the viewing angle Ψ becomes wider, ideally, Ψ = 180 °, p = λ / 2. Therefore, in the spatial light modulator 10, the smaller the pixel length (pitch of magnetic fine wires 41, 42, 43) p1 _y , p2 _y , and p3 _y , the wider the viewing area angle Ψ _y (see FIG. 7) in the Y direction. .. Although it depends on the number of pixels of the spatial light modulator 10 and the application of the holography device 20, the pixel length is such that the observer can visually recognize the entire stereoscopic image with both eyes with the Y direction as the horizontal (H) direction. It is preferable that p _y is 4 times or less (Ψ _y ≧ 14.36 °) of the center wavelength λ of the incident light Li, and more preferably 2 times or less (Ψ _y ≧ 28.95 °). From equations (1) to (6), the pixel length p _y is minimized by p1 _y = λ _B , W1 = λ _B / 2, p2 _y = λ _G , W2 = λ _G / 2, p3. _y = λ _R , W3 = λ _R / 2, and at this time, Ψ _y = 60 °.
Ψ = 2 sin ^-1 (λ / 2p) ・ ・ ・ (9)

Since the light emitted from the monochromatic space optical modulator 1 is the light reflected by the magnetic thin wire 4 continuous in the X direction, it is not diffracted in the X direction and the axis is in the X direction along each magnetic thin wire 4. It becomes a cylindrical wave (pillar surface wave) parallel to. In this emitted light Lo, only the light generated on the magnetic thin wire 4 and reflected in the magnetic domain in a specific magnetization direction passes through the polarizer PFo and is divided in the X direction. As a result, depending on the pixel pattern, the magnetic zone length of the magnetic thin wire 4 may be small, and the emitted light Lo transmitted through the polarizing element PFo may be partially diffracted in the X direction. Therefore, the outgoing light L _B o transmitted through the polarizer PFo regardless pattern of pixels, L _G o, L _R o of such behavior is stabilized, the pixel length in the X direction of the first layer spatial light modulator 11 p1 _x is set equal to or larger than the central wavelength lambda _B of the light _{L B (p1 x ≧ λ B} ) is preferably, and more preferably a maximum wavelength lambda _Bmax least (p1 _x ≧ λ _Bmax). Similarly, the pixel length p2 _{x in} the X direction of the second layer spatial light modulator 12 is preferably set to p2 _x ≧ λ _G, and more preferably p2 _x ≧ λ _Gmax . The pixel length p3 _{x in} the X direction of the third layer spatial light modulator 13 is preferably set to p3 _x ≧ λ _R, and more preferably p3 _x ≧ λ _Rmax . In the present embodiment, the pixel lengths of the first, second, and third layer spatial light modulators 11, 12, and 13 are aligned and set to p1 _x = p2 _x = p3 _x = p _X ≧ λ _R. The arrangement of the pixels in the X direction at each of the pixel X-direction lengths p1 _x , p2 _x , p3 _x , and the magnetic thin wires 41, 42, and 43 is described in the method of driving the spatial light modulator described later. Set at the time of writing.

(Manufacturing method of spatial light modulator)
The spatial light modulator 10 according to the present embodiment is the same as the conventional domain wall moving type spatial light modulator (see Patent Document 6) and the magnetic recording medium, respectively, for each of the monochromatic spatial light modulators 11, 12, and 13. The substrates 61, 62, 63, particularly the back surfaces of the substrates 61, 62, are ground and polished to reduce the thickness to a desired thickness, and then superposed. Means for superimposing the monochromatic spatial light modulator 11, 12, 13 is not particularly limited as long as it does not interfere light L _G, the transmission of L _R. Specifically, a method of bonding the entire surface with an adhesive made of a translucent resin, a surface activation bonding or an atomic diffusion bonding applied to a laminated semiconductor device, and a peripheral portion (outside the pixel region IA3) are cured. A method of grasping with a tool and fixing each other can be applied, and at that time, a certain gap (gas such as air or an inert gas or vacuum) may be included between them. Further, in the spatial light modulator 10, an external magnetic field is applied as an initial setting before use (writing), and the magnetization directions of all the magnetic thin wires 41, 42, and 43 are set to a predetermined direction (vertical magnetic anisotropy material). If it consists of, for example, it is aligned downward). This initial setting may be made for the completed spatial light modulator 10, individually for the monochromatic spatial light modulators 11, 12, 13 before superposition, and further for the monochromatic space. It can be carried out at any stage after the magnetic material forming the magnetic thin wires 41, 42, 43 is formed in the middle of each of the manufacturing processes of the light modulators 11, 12, and 13.

[Holography equipment]
A holographic apparatus using the spatial light modulator according to the embodiment of the present invention as a hologram will be described with reference to FIG. The holography apparatus 20 according to the present embodiment includes a spatial light modulator 10, a multi-wavelength light source device 2, an output optical system 3, and a first drive unit 91, a first drive unit 91, as means for writing a pixel array to the spatial light modulator 10. It includes two drive units 92 and a third drive unit 93. The holography apparatus 20 is a horizontal parallax type, and therefore, the spatial light modulator 10 is arranged so that the X direction (the thin line direction of the magnetic thin lines 41, 42, 43) displays the vertical (V) direction.

Multi-wavelength light source unit 2, different incident light L _B i wavelength range, L _G i, a L _R i, one of the light (white light) is irradiated to the spatial light modulator 10 as L _W i. The multi-wavelength light source device 2 includes a laser light source 21, 22, 23, a synthetic optical system DP, a collimator lens CL, and a polarizer PFi. Laser light source 21 emits light L _B of the central wavelength lambda _B. Laser light source 22 emits light L _G of the center wavelength lambda _G. The laser light source 23 irradiates light L _R with a center wavelength λ _R. The synthetic optical system DP is, for example, a Philips type dichroic prism, which synthesizes light incident from three directions by aggregating the optical axes in one of the three directions. Therefore, the optical axis combining optical system DP are disposed such that the spatial light modulator 10, The laser light source 22 so as to be incident light L _G in the same direction is disposed. Collimator lens CL, the light L _B is irradiated to the spatial light modulator 10, L _G, the L _R, and the parallel light flux of the pixel region IA3 or more of the width of the third layer spatial light modulator 13 (diameter) To do. Polarizer PFi, the light L _B, which is the parallel light, L _G, the L _R, a specific one polarization component of the light (polarized light) L _B i, L _G i, to L _R i. Collimator lens CL or more polarizers PFi, is provided for each laser light source 21, 22, 23, before the light L _B are synthesized by combining optical system DP, L _G, it may be arranged for transmitting L _R .. Also, as a synthetic optical system DP, and a cross dichroic prism, transmitted through the dichroic mirror reflects light L _G and transmits light L _B (beam splitter), and reflects the light L _R and the light L _B, the L _G It may be combined with a dichroic mirror. Image light L _B, L _G, L _R, the width of each of the wavelength range, wherein the manner is not particularly limited so long as it does not overlap with each other, reproduced by holography device 20 as the respective wavelength ranges is narrow The color tone of VI becomes clear. Therefore, the laser light irradiated from the laser light source 21, the light L _B by transmitting color filter, L _G, may be obtained L _R.

Output optical system 3, emits light L _B o emitted from the spatial light modulator 10, L _G o, the L _R o, and outputs the three-dimensional image VI of the desired size. Output optics 3 includes outgoing light L _B o, L _G o, in order from the input side of L _R o, and a polarizer (analyzer) PFo, a magnifying optical system 31, a. Polarizer PFo is to shield the polarization of a particular orientation, spatial emitted light emitted from the light modulator _{10 L B o, L G o} , of L _R o, the incident light _{L B i, L G i,} L and transmits light optical rotation in a particular orientation relative to _R i. Polarizer PFo is disposed on the input side of a position where the emitted light _{L B o, L G o,} L R o is imaged colors image vI _B of, vI _G, the vI _R (see FIG. 7). The magnifying optical system 31 includes one or a plurality of lens arrays in which lenses and microlenses are two-dimensionally arranged according to the dimensions of the pixel regions IA1, IA2, and IA3 of the spatial optical modulator 10 and the dimensions of the image VI to be reproduced. FIG. 5 shows two lenses). The lens of the magnifying optical system 31 includes a cylindrical lens and a toroidal lens as needed, and adjusts the aspect ratio of the stereoscopic image VI.

In holography device 20, as polarizer PFo on the optical path of the incident light L _W i is not arranged, and the outgoing light L _B o, L _G o, as polarizer PFi on the optical path of L _R o is not disposed , The multi-wavelength light source device 2 and the output optical system 3 are arranged. Specifically, the incident angle α (0 ° ≤ α <90 °) of the incident light L _Wi is adjusted according to the arrangement of the multi-wavelength light source device 2, or the multi-wavelength light source device 2 or the output optical system is used as necessary. 3 comprises a beam splitter (half mirror), the incident light L _W i or outgoing light L _B o, L _G o, reflects the L _R o. When the magnetic thin wire 4 is made of a vertically magnetic anisotropy material, the magneto-optical effect is higher as the incident angle α of the incident light Li is closer to 0 °, and α = 0 °, that is, incident perpendicularly to the incident surface (XY plane). It becomes maximum when light Li is incident. Specifically, it is preferable that α ≦ 30 °. The emission angle of the emitted light Lo depends on the ratio of the pixel length p _{y to} the wavelength λ in addition to the incident angle in the Y direction.

The first drive unit 91 is a writing means of the first layer spatial light modulator 11, the second drive unit 92 is a writing means of the second layer space optical modulator 12, and the third drive unit 93 is a writing means of the third layer space optical modulator 13. Each includes a pulse current source 7, a magnetization means 8 (see FIG. 4), an image data receiving means, and a processing means (not shown). The pulse current source 7 of the first drive unit 91 is connected to all the magnetic thin wires 41 of the first layer spatial light modulator 11 to the electrodes 51n and 51p at both ends thereof, and a DC pulse current is transmitted from the electrode 51p to the electrode 51n. Supply. Similarly, the pulse current source 7 of the second drive unit 92 supplies DC pulse current to all the magnetic thin wires 42 of the second layer spatial light modulator 12 by connecting them to the electrodes 52n and 52p at both ends thereof. Further, the pulse current source 7 of the third drive unit 93 is connected to all the magnetic thin wires 43 of the third layer spatial light modulator 13 to the electrodes 53n and 53p at both ends thereof to supply a DC pulse current. As shown in FIG. 4, the pulse current source 7 may be connected to all the magnetic thin wires 4 of the monochromatic spatial light modulator 1 so as to supply a pulse current in parallel, or may be selectively connected to the magnetic thin wires 4. It may be a structure that can be connected.

The magnetizing means 8 of the first driving unit 91 writes the magnetic thin wire 41 of the first layer spatial light modulator 11 in the writing area 41w in a binary manner (upward or downward) based on the signal input to the first driving unit 91. ) Is the magnetization direction. The magnetization means 8 of the second drive unit 92 sets the magnetic wire 42 of the second layer spatial light modulator 12 in the magnetization direction based on the signal input to the second drive unit 92 in the writing region 42w. The magnetization means 8 of the third drive unit 93 sets the magnetic wire 43 of the third layer spatial light modulator 13 in the magnetization direction based on the signal input to the third drive unit 93 in the writing region 43w. The magnetizing means 8 includes, for example, a magnetic head having a structure similar to that of a recording (writing) head of a magnetic recording medium, and a current source that selects a direction and supplies a current to the coil of the magnetic head, and the magnetic head is magnetic. It is arranged so as to face the writing area 4w of the thin line 4. Each of the magnetizing means 8 does not have to be provided with a current source. For example, in each of the drive units 91, 92, and 93, the magnetizing means 8 has two current sources, a forward current source and a reverse current source, and a switch (matrix switcher). ), The switch connects the magnetic head facing each magnetic wire 4 to a forward current source or a reverse current source based on the input signal. Further, since the magnetic head of the magnetization means 8 is preferably close to the magnetic thin wire 4 (writing area 4w), the magnetic head is fixedly provided to the monochromatic spatial light modulator 1 and the current source is externally provided to the magnetic head. It may be configured to connect to. Further, the magnetization means 8 may be provided with a current magnetic field generation mechanism such as a half-turn coil or a one-turn coil instead of the magnetic head, and the current source may select and generate a magnetic field in two directions in the mechanism.

(How to drive the spatial light modulator)
The method of setting (writing) each pixel of the monochromatic spatial light modulators 11, 12, and 13 of the spatial light modulator 10 in the magnetization direction based on the image data is a conventional domain wall moving type spatial light modulator (spatial light modulator). This is the same as in Patent Document 6). The first drive unit 91 receives a blue digital signal of image data from the outside (a connected personal computer or the like), the second drive unit 92 receives a green digital signal, and the third drive unit 93 receives a red digital signal. To receive. The first driving unit 91 divides one frame of the received image data into a group of pixels (pixel strings) arranged in a row in the vertical (V) direction, and divides the data of the pixel rows into the pixels. The data is output to the magnetizing means 8 arranged on the magnetic thin wire 41 of the first layer space optical modulator 11 corresponding to the row. Then, the first drive unit 91 controls the magnetization means 8 in synchronization with the pulse current supplied by the pulse current source 7 to generate a magnetic field in the direction corresponding to the signal during the pulse stop time (base period). .. For example, when the signal '1' indicates "bright", the magnetic field is upward, and since '0' indicates "dark", the magnetic field is downward. Similarly, in the second and third layer spatial optical modulators 12 and 13, the second and third drive units 92 and 93 divide the received image data into pixel string data and correspond to the pixel string. It is output to the magnetization means 8 arranged on the magnetic thin wires 42 and 43 to generate a magnetic field in the magnetization means 8.

The pulse current supplied by the pulse current source 7 has a current value, a pulse width (peak period), and a stop time (base period) set in each of the drive units 91, 92, and 93. The current value of the pulse current is set to be equal to or higher than the current density for moving the magnetic domain wall that divides the magnetic thin wire 4 in the thin wire direction, based on the material and cross-sectional area (product of width W and thickness) of the magnetic thin wire 4. Further, the pulse current is set to a time during which the pulse width (peak period) moves the domain wall by the pixel length p _X based on the domain wall moving speed in the magnetic wire 4 calculated from the current value, while the stop time. (Base period) is set to be longer than the time required for the magnetizing means 8 to write the magnetic domain wall 4 to the writing area 4w. Such a pulse current is supplied by the number of pixels in the X direction, and the magnetization means 8 generates a magnetic field for each pulse base period. Further, for each of the monochromatic spatial light modulators 11, 12, and 13, the number of pulses after writing the last pixel in the pixel array is set according to the distance from the writing area 4w of the magnetic thin wire 4 to the pixel area IA. The pulse width may be set so that the domain wall is moved by the pixel length p _X with two or more pulses.

In the spatial light modulator 10, each of the monochromatic spatial light modulators 11, 12, and 13 may be written in parallel by the drive units 91, 92, and 93, or may be executed one by one in order. Also, the odd-numbered sequence and the even-numbered sequence in the monochromatic spatial light modulator 1 may be executed in a plurality of times. Further, writing in the upward magnetization direction and writing in the downward magnetization direction may be alternately performed for each pulse. In this case, the pulse current source 7 is configured to be selectively connectable to each magnetic wire 4, and during the peak period immediately after writing, the pulse current is supplied only to the written magnetic wire 4 to move in the magnetic domain. Let me. However, in writing by any of the procedures, the time required to write the image for one frame is sufficiently shortened, and specifically, it is 1/2 or less of 1/60 second (≈16.7 ms). Is preferable, and even shorter is preferable. The shorter the writing (rewriting) time of the image in one frame, the higher the ratio of the real time for displaying the image can be increased, and the reproduced image VI becomes brighter. When writing is executed in parallel by the drive units 91, 92, and 93, the respective processes may be independent (asynchronous) from each other, or the pulse currents of the pulse current source 7 may be matched and synchronized. You may let me.

(Operation of holography equipment)
Reproduction of a full-color stereoscopic image by a holographic apparatus using the spatial light modulator according to the first embodiment will be described with reference to FIGS. 6, 7, and 5 including the optical modulation operation of the spatial light modulator. .. In FIG. 6, the monochromatic spatial light modulators 11, 12, and 13 show only magnetic thin wires 41, 42, and 43, respectively, and the substrates 61, 62, 63 and the insulating layer 64 are omitted. In FIG. 7, for the sake of brevity, the monochromatic spatial light modulator 1 is illustrated in a configuration including eight magnetic thin wires 4, the insulating layer 64 is omitted, and the arrows attached in the magnetic thin wires 4 indicate the magnetization direction. Represent.

When the incident light L _W i from the multi-wavelength light source device 2 is irradiated to the spatial light modulator 10 from above, as shown in FIG. 6, the light L _B i of the incident light L _W i is, the uppermost is reflected by the magnetic wire 41 in one layer spatial light modulator 11, is emitted upward of the spatial light modulator 10 becomes emission light L _B o. Further, the light L _G i, L _R i of the incident light L _W i is the first layer spatial light modulator 11 (magnetic wire 41, the insulating layer 64, the substrate 61) through the second layer spatial light modulator Reach vessel 12. The light L _G i is reflected by the magnetic thin wire 42 to become the emitted light L _G o and is emitted upward. Outgoing light L _G o is emitted upward of the spatial light modulator 10 is transmitted through the first layer spatial light modulator 11 similarly to the incident light L _G i. On the other hand, the light L _R i, the second layer spatial light modulator 12 (magnetic wire 42, the insulating layer 64, the substrate 62) further passes through and reaches the third layer spatial light modulator 13. Then, the light L _R i is reflected by the magnetic thin wire 43 to become the emitted light L _R o and is emitted upward. Outgoing light L _R o, the second layer spatial light modulator 12, is emitted upward of the spatial light modulator 10 sequentially passes through the first layer spatial light modulator 11. In FIG. 6, the incident light _{L B i, L G i,} L R i is represented by the hatched or hollow arrow. On the other hand, outgoing light _{L B o, L G o,} L R o is the light diffracted light interferes as described below, representing each part by a thick arrow.

Here, the optical modulation operation of the spatial light modulator according to the present embodiment and the reproduction of a stereoscopic image of monochromatic light by the monochromatic spatial light modulator will be described with reference to FIG. 7. The magnetic domain of the magnetic wire 4 is divided in the direction of the magnetic domain by the writing described in the driving method of the spatial light modulator, and each magnetic domain indicates an upward or downward magnetization direction. In the cross section shown in FIG. 7, magnetic domains in the downward magnetization direction are generated in the fifth and sixth magnetic thin wires 4 from the left, and magnetic domains in the upward magnetization direction are generated in the other magnetic thin wires 4. When light Li, which is one polarization component and parallel light, is incident on the monochromatic spatial light modulator 1 from above, it is reflected by the magnetic thin wire 4 and the emitted light Lo is emitted upward. By reflecting from the magnetic thin wire 4 having a width W smaller than the wavelength λ, the emitted light Lo is diffracted and spread in the width direction, that is, the Y direction of the magnetic thin wire 4, and is a cylindrical wave (pillar surface wave) along the magnetic thin wire 4. ). Further, due to the magneto-optical effect, the direction of polarization of the emitted light Lo changes according to the magnetization direction in the incident region of the magnetic thin wire 4, and the angle + θk in the magnetic domain in which the magnetization direction is upward and the angle −θk in the magnetic domain which is downward. Rotate with. In FIG. 7, the incident light Li is represented by a linear arrow, and further, a double-headed arrow indicating the direction of polarization is attached. Similarly, the emitted light Lo is represented by a linear arrow diverging from the magnetic thin wire 4 and emitted with a double-headed arrow indicating the direction of polarized light, and at an angle −θk with respect to the incident light Li. Let the direction of the rotated polarized light be the Y direction (represented by the longest double-headed arrow).

In monochromatic spatial light modulator 1, the magnetic nanowire 4 is arranged at a pitch p _y number times the wavelength λ of the incident light Li, the light Lo emitted diverge from each magnetic thin wire 4, Strengthen each other in phase by interference. In FIG. 7, the wave surface of the light in which the plurality of lights interfere is represented by a wavy line. Further, the interfering emitted light Lo includes polarized light rotated at an angle + θk and polarized light rotated at an angle −θk with respect to the incident light Li. A polarizer PFo is arranged above the spatial light modulator 10 (monochromatic spatial light modulator 1) so as to block polarized light in the Y direction. Therefore, after passing through the polarizer PFo, the emitted light Lo weakens or further disappears in the portion including the light emitted from the magnetic domain in which the magnetization direction of the magnetic thin wire 4 is downward to form a light-dark pattern. Then, the emitted light Lo transmitted through the polarizing element PFo forms an image vI of monochromatic light at a position at a predetermined distance from the emitting surface of the monochromatic spatial light modulator 1. The emission surface of the monochromatic spatial light modulator 1 is a light reflecting surface, that is, the surface of the magnetic thin wire 4, and this surface becomes the hologram surface P of the holography apparatus 20.

Outgoing light L _B o emitted from the spatial light modulator _{10, L G o, L R} o passes through the polarizer PFo output optical system 3 disposed above the spatial light modulator 10, as described above In addition, each pixel is formed in a light / dark pattern (blue and black, green and black, red and black) according to the magnetization direction. Polarizer PFo outgoing light transmitted through the _{L B o, L G o,} L R o is imaged image vI _B of each light color, vI _G, vI _R a (vI in Figure 7). These 3 Tsunozo vI _B, vI _G, vI _R forms an image in an enlarged or reduced in the same position in the desired size and aspect ratio by enlarging optical system 31 of the output optical system 3, by mixing three-dimensional image of a full color It becomes VI.

Holography device 20, the outgoing light L _B o of the spatial light modulator _{10, L G o, L R} o each image vI _B by, vI _G, same position vI _R, without image aligned in the same size It may be corrected by the magnifying optical system 31 so that the image formation position and the dimensions are aligned on the output side of the output optical system 3. Image vI _B by spatial light modulator 10, vI _G, the imaging position and size of the vI _R, may be adjusted in light-dark pattern for each pixel of the monochromatic spatial light modulator 11, 12, 13, The positions of the hologram surfaces P1, P2, and P3 may be adjusted. Further, the deviation in the X direction can be corrected by the pulse current source 7 by moving the pixel sequence on the magnetic thin wires 41, 42, 43 and adjusting the pixel lengths p1 _x , p2 _x , and p3 _x .

Incidentally, the light L _B i is incident on the insulating layer 64 between the magnetic wire 41, or the first layer spatial light modulator 11 by the full with the magnetic wire 41 which transmits part not reflected transmitted, even if the emission is reflected by the magnetic thin wire 42 of the second layer spatial light modulator 12, since such light L _B do not interfere not aligned is the outgoing light L _B o and pitch that is reflected by the magnetic wire 41 , it does not affect the image vI _B. Light L _B emitted is reflected by the magnetic thin wire 43 of the first layer spatial light modulator 11 and the second layer spatial light modulator 12 is transmitted through the third layer spatial light modulator 13, L _G is the same. Thus, the spatial light modulator 10, by providing by laminating a pixel length p1 _y, p2 _y, p3 _y monochromatic spatial light modulator 11, 12, 13 of the formula (8), the light L _B i , L _G i, and enters the laminating direction collectively L _R i, a light L _B i in the first layer spatial light modulator 11, the light L _G i in the second layer spatial light modulator 12, light L the _R i in the third layer spatial light modulator 13, light emitted L _B o which each is optically modulated, L _G o, as L _R o only effective light, to obtain a three-dimensional image VI of full-color holography device 20 Can be done.
p1 _y / λ _B = p2 _y / λ _G = p3 _y / λ _R ... (8)

(Modified example of spatial light modulator)
In the spatial light modulator 10, the “bright” pixel may be a magnetic domain in the downward magnetization direction, and the “dark” pixel may be a magnetic domain in the upward magnetization direction. In this case, in the holography apparatus 20, the polarizer PFo is used. , It is arranged so as to block the light emitted from the magnetic domain whose magnetization direction is upward. The polarization direction of the outgoing light L _B o transmitted through the polarizer PFo, L _G o, L magnetization direction of the magnetic domain for emitting _R o is may be different monochromatic spatial light modulator 11, 12, 13, this In this case, the monochromatic spatial light modulators 11, 12, and 13 individually set the magnetization directions of the light / dark pixels. Further, the sizes of the car rotation angles θk1, θk2, and θk3 of the magnetic thin wires 41, 42, and 43 may be different from each other. In these cases, the outgoing light _{L B o, L G o,} L R o respectively, so that the polarization of the person who is shielded by the polarizer PFo are aligned in the same direction, the incident light L _B i, L _G i, The direction of polarization of L _R i is adjusted individually. Therefore, multi-wavelength light source device 2, provided with a polarizer PFi each laser light source 21, the light L _B before being combined by the combining optical system DP, L _G, L _R each predetermined polarization L _B i, L _G i, L _R i.

Spatial light modulator 10, below the second embodiment (FIG. 9, see FIG. 11) similarly to the first light L _G by absorbing light L _B between the second layer spatial light modulator 11 and 12, may comprise a first optical filter LF1 for transmitting L _R, also the second, the second optical filter that transmits light L _R by absorbing light L _G between the third layer spatial light modulator 12, 13 LF2 may be provided. By providing the first optical filter LF1 between the magnetic thin wires 41 and 42, the light L _Bi transmitted through the first layer spatial light modulator 11 is reflected by the magnetic thin wires 42 and the magnetic thin wires 43 and emitted. Can be prevented. Similarly, by providing the second optical filter LF2 between the layers of magnetic thin wire 42 and 43, prevent the light L _G i which has passed through the second layer spatial light modulator 12, and emits the reflected magnetic wire 43 can do. The configuration of the optical filters LF1 and LF2 will be described in the second embodiment. When the optical filters LF1 and LF2 have an incident angle dependence, the incident angle α of the incident light L _Wi to the spatial light modulator 10 is set to the corresponding incident angle α (> 0 °). Spatial light modulator 10, by adopting such a structure, emitted light _{L B o, L G o,} L R o non, it is emitted light which is not modulated with a predetermined magnetic wire 41, 42 and 43 image It is possible to suppress the occurrence of color bleeding and the like.

As described above, the reflectance and transmittance of the thin magnetic wires 41, 42, 43 may be controlled by the base film. Specifically, the first layer spatial light modulator 11 includes the underlying magnetic thin wire 41, the light L _G and reflects the light L _B, a dielectric multilayer film that transmits L _R. The second layer spatial light modulator 12, the base of the magnetic wire 42 comprises a dielectric multilayer film that transmits light L _R reflected light L _G. Third layer spatial light modulator 13, the base of the magnetic thin wire 43, or provided with a dielectric multilayer film which reflects light L _R, and an insulating film which transmits light L _R, further under the insulating film A metal film that reflects light L _R is provided. The dielectric multilayer film is obtained by alternately and repeatedly laminating two or more types of insulating films (dielectric films) having different refractive indexes, similarly to a known reflective optical filter. Spatial light modulator 10, by adopting such a structure, it is possible to increase the quantity of emitted light _{L B o, L G o,} L R o. Since the reflectance of the dielectric multilayer film has an incident angle dependence, the incident angle α of the incident light L _Wi to the spatial light modulator 10 is set to the corresponding incident angle α (> 0 °). ..

In the monochromatic spatial light modulator 1 (11, 12, 13), the electrodes 5n and 5p are respectively arranged in a single row in FIG. 2, but may be arranged in a staggered manner. In particular, the first layer spatial light modulator 11 having relatively small pixels and magnetic fine wires 41 arranged side by side at a narrow pitch can be easily connected to the pulse current source 7 by arranging the electrodes 51n and 51p in a staggered manner. Further, in the monochromatic space optical modulator 1, it is sufficient that the magnetic fine wires 4 are arranged in a straight line and parallel to the X direction in the pixel region IA, and otherwise, the shift movement of the magnetic domain due to the pulse current is not affected. It may be curved as long as it has a moderately gentle curvature. For example, in the first layer spatial light modulator 11, the magnetic wire 41 is bent outward in the Y direction so as to widen the distance between the magnetic wire 41 and the adjacent magnetic wire 41 outside the pixel region IA1, and the electrodes 51n connected to both ends. , 51p and the pitch of the writing area 41w can be widened. By having such a structure, the first layer space optical modulator 11 can easily connect the pulse current source 7 to the electrodes 51n and 51p even if the pixels are relatively small, and all the magnetic thin wires 41 are written. The magnetization means 8 (magnetic head) is likely to face each of the inclusion regions 41w, and it is unlikely to affect the adjacent magnetic thin wire 41 during writing.

The monochromatic spatial light modulator 1 may be configured to include other than the current source of the magnetization means 8 as in the spatial light modulator (for example, Patent Documents 4 and 5) in which the magnetic material is separated for each pixel. For example, in order to perform writing by the spin injection magnetization reversal method, the monochromatic spatial light modulator 1 includes a TMR element structure in which the magnetic thin wire 4 becomes a magnetization free layer in the writing region 4w, and a pair of electrodes connected above and below the TMR element structure. .. Specifically, in the writing area 4w, an insulating film such as MgO, Al ₂ O ₃ , MgAl ₂ O ₄ is sandwiched above or below the magnetic thin wire 4, and a magnetic film having a larger coercive force than the magnetic thin wire 4 (magnetization). (Fixed layer) is laminated to form an electrode with a metal electrode material before forming the magnetic thin wire 4 and after forming the magnetized fixed layer (see Patent Document 6). Further, the magnetic thin wire 4 is formed to have a thickness of 10 nm or less so that spin injection magnetization reversal is possible, and the length of one side of the writing region 4w, that is, the length in the thin wire direction and the width W of the magnetic thin wire 4 is 500 nm. Below, it is preferably formed to be 300 nm or less. In this case, the current source of the magnetization means 8 is connected to the pair of electrodes to supply a current that reverses the spin injection magnetization of the magnetic wire 4 in the writing region 4w. By having such a structure, the monochromatic spatial light modulator 1 can be accurately magnetized (written) with respect to each writing region 4w of the magnetic fine wires 4 arranged side by side at a narrow pitch.

Further, in the magnetic field application method, a lead wire may be arranged so as to surround the writing area 4w in a plan view, and a current may be passed through the lead wire to generate a magnetic field. However, it is preferable to provide a magnetic shield layer with a magnetic film on the magnetic thin wire 4 in this region so that the magnetic field is not applied to the outside of the writing region 4w of the magnetic fine wire 4, particularly on the pixel array side. Further, as a simpler structure, the two conductors may be extended in the Y direction so that the magnetic field is applied in the same direction over the writing region 4w of all the magnetic thin wires 4 of the monochromatic spatial light modulator 1. By passing currents through the two conductors in opposite directions, a magnetic field is generated upward or downward in the writing region 4w. Further, the pulse current source 7 is configured to be selectively connectable to each magnetic wire 4, and the pulse current is supplied only to the magnetic wire 4 which is the direction of the magnetic field generated by the magnetizing means 8 in the immediately preceding base period. And move the magnetic domain. The spatial light modulator 10 does not have to have the same writing method as the monochromatic spatial light modulators 11, 12, and 13. For example, the first layer spatial light modulator 11 having a narrow width W1 and pitch p1 _{y of} the magnetic thin wire 41 and a small area of the writing area 41w can be used as a spin injection magnetization reversal method, and other second and third layer spatial light. The modulators 12 and 13 can be of the magnetic field application method.

The spatial light modulators 10 are spaced apart so that the monochromatic spatial light modulators 11, 12, and 13, respectively, insulate adjacent magnetic wires 4 and 4 from each other and prevent them from magnetically affecting each other. Installed side by side. Here, in the field of a magneto-optical recording medium such as a magneto-optical disk in which one pixel is replaced with one bit and a magnetic thin wire is used as a continuous recording area (track), parallel beams formed on a substrate in order to increase the recording density. A land-and-groove recording method is known in which recording areas are provided both inside (bottom) and top of a large number of grooves. When the same structure is applied to the spatial light modulator of the domain wall movement type, the magnetic fine wires are arranged side by side without any gap in the plan view, so that the aperture ratio of the pixel can be set to 1. Hereinafter, the spatial light modulator according to the modified example of the embodiment of the present invention will be described with reference to FIG. The same elements as those in the above-described embodiments (see FIGS. 1 to 7) are designated by the same reference numerals, and the description thereof will be omitted.

Spatial light modulator 10A according to a modification of the embodiment of the present invention, from the side (top) in the order of incidence of light L _W i, the first layer spatial light modulator 11A, second layer spatial light modulator 12A, A third layer spatial light modulator 13A (collectively, monochromatic spatial light modulators 11A, 12A, 13A) is provided in an overlapping manner. The first layer spatial light modulator 11A, like the first layer spatial light modulator 11 of the spatial light modulator 10 according to the embodiment, the light L _B i of the incident light L _W i reflecting causes modulated And emit. The second layer spatial light modulator 12A, like the second layer spatial light modulator 12, the reflected light L _G i of the incident light L _W i, emitted by modulated. Then, a third layer spatial light modulator 13A, like the third layer spatial light modulator 13, the reflected light L _R i of the incident light L _W i, emitted by modulated. The monochromatic spatial light modulators 11A, 12A, 13A have substantially the same structure except for the dimensions in a plan view, like the monochromatic spatial light modulators 11, 12, 13 of the first embodiment, and the monochromatic spatial light is not specified. It is referred to as a modulator 1A.

As shown in FIG. 8, the monochromatic space optical modulator 1A includes a substrate 6, a plurality of magnetic thin wires 4 extending in the X direction provided on the substrate 6, and electrodes 5n and electrodes connected to both ends of each magnetic thin wire 4. It is provided with an insulating layer 64 that covers 5p and the magnetic thin wire 4. The number of the magnetic thin wires 4 is the number of pixels in the Y direction of the pixel array, but in FIG. 8, for the sake of brevity, an example is provided in which eight magnetic wires are provided. Further, in the monochromatic spatial light modulator 1A, the odd-numbered magnetic fine wires 4 are formed on the surface of the substrate 6 in the Y direction, and the even-numbered magnetic fine wires 4 are deposited on the substrate 6 in a thickness h of the insulating layer 64. It is formed on the surface. That is, in the monochromatic spatial light modulator 1A, the magnetic thin wires 4 are alternately arranged one by one in a staggered manner. The magnetic thin wires 4 are magnetic fine wires 41, 42, 43 in each of the monochromatic spatial light modulators 11A, 12A, and 13A, and have the same configuration as that of the above embodiment except for the arrangement, dimensions, and the like. The electrodes 5n, 5p, the substrate 6, and the insulating layer 64 have the same configurations as those in the above embodiment.

In the monochromatic spatial light modulator 1A, the distance between the lower magnetic wire 4 and the upper magnetic wire 4 adjacent to each other in the plan view in the Y direction is not particularly specified, and may be 0 or more, that is, do not overlap. Monochromatic spatial light modulator 1A, by such a structure, the magnetic nanowire 4 together with each other (h-t) or more, or (2p _y -W) with juxtaposed with a clearance of at least (t: (Thickness of the magnetic thin wire 4), the pitch can be narrowed to the same value as the width W in a plan view ( _py ≧ W). In particular, as shown in FIG. 8, by _py = W, that is, when the magnetic fine wires 4 are arranged side by side without gaps in a plan view, the magnetic fine wires 4 can be easily formed as described later.

Further, in the monochromatic spatial light modulator 1A, the lower magnetic wire 4 is formed longer than the upper magnetic wire 4 by extending in both directions, and the upper magnetic wire 4 is formed on the outside in the X direction (an electrode connected to the magnetic wire 4). A writing area 4w of the lower magnetic thin wire 4 is provided on the outside of 5n). Then, the insulating layer 64 has a stepped shape at both ends in the X direction so that not only the upper surface but also the upper surfaces of the electrodes 5n and 5p connected to the lower magnetic wire 4 are exposed and the magnetic field application to the writing region 4w is not hindered. It has been thinned to. With such a structure, the monochromatic spatial light modulator 1A can easily connect the pulse current source 7 to the electrodes 5n and 5p for the magnetic thin wires 4 in the upper and lower stages, respectively, and in each writing area 4w. Writing can be performed with the magnetizing means 8 facing each other in close proximity to each other.

Here, the length of the path of the incident light Li from the height position of the upper magnetic wire 4 to the height position of the lower magnetic wire 4 determines the approach angle of the incident light Li to be α _i (0 ° ≤ α _i). If <90 °), it is expressed as (h / cos α _i ). Further, when the refractive index of the insulating layer 64 and n _i, the optical distance (optical path length) because a _{(n i × d / cosα i} ), the outgoing light Lo reflected in the upper part of the magnetic nanowire 4 'lower The difference in the optical path length is twice that of the emitted light Lo'reflected by the magnetic thin wire 4. From this, when the following equation (10) is established (N: natural number), the emitted light Lo reflected by the upper and lower magnetic thin wires 4 and 4 has the same phase and emits by strengthening the amount of light with each other. Since the approach angle α _i is the angle of the incident light Li traveling through the insulating layer 64, the incident angle α ₀ (0 ° ≦ α ₀ <90 °) from the outside (in the air, the refractive index is 1). On the other hand, it is expressed by the following equation (11). Therefore, the equation (10) can be expressed by the following equation (12).
h = N / 2 × λ × cos α _i / n _i・ ・ ・ (10)
^{_{α i = sin -1 (sinα 0}} / n i) ··· (11)
h = N / 2 × λ × √ (n _i ² −sin ² α ₀ ) / n _i ² ··· (12)

Therefore, the step h1 of the magnetic wire 41 in the first layer space optical modulator 11A, the step h2 of the magnetic wire 42 in the second layer space optical modulator 12A, and the step h3 of the magnetic wire 43 in the third layer space optical modulator 13A are , Represented by the following equations (13), (14) and (15), respectively, and when the insulating layer 64 is made of the same material, they are different from each other in proportion to the wavelength of the light to be modulated. Note that N in the following equations (13), (14), and (15) is not particularly specified as long as it is a natural number, and it does not have to be the same value, but it is preferably small, and N = 1 is the most preferable. .. When N is large, the steps h1, h2, and h3 become large, making it difficult to form the magnetic thin wire 4 by the manufacturing method described later, and the insulating layer 64 becomes thick and the light is attenuated, so that the reflection from the magnetic thin wire 4 Light causes a difference in the amount of light between the upper and lower stages.
h1 = N / 2 × λ _B × √ (n _i ² −sin ² α ₀ ) / n _i ² ··· (13)
h2 = N / 2 × λ _G × √ (n _i ² −sin ² α ₀ ) / n _i ² ··· (14)
h3 = N / 2 × λ _R × √ (n _i ² −sin ² α ₀ ) / n _i ² ··· (15)

The width W1 and pitch p1 _y of the magnetic wire 41 in the first layer spatial light modulator 11A, the width W2 and pitch p2 _y of the magnetic wire 42 in the second layer spatial light modulator 12A, and the third layer spatial light modulator 13A. The width W3 and the pitch p3 _y of the magnetic thin wire 43 in the above are the same as the above-described embodiment, of the formulas (1), (3), (5), and (8). Therefore, the most preferable examples in this modification are W1 = p1 _y = λ _B / 2, W2 = p2 _y = λ _G / 2, W3 = p3 _y = λ _R / 2, and in this case, the equation (9) Therefore, Ψ _y = 180 °. As described above, the spatial light modulator 10A can have a larger viewing area angle Ψ _y than the spatial light modulator 10 according to the embodiment.
λ _B / 2 ≦ W1 <λ _B ... (1)
λ _G / 2 ≦ W2 <λ _G ... (3)
λ _R / 2 ≦ W3 <λ _R ... (5)
p1 _y / λ _B = p2 _y / λ _G = p3 _y / λ _R ... (8)
Ψ = 2 sin ^-1 (λ / 2p) ・ ・ ・ (9)

On the other hand, the pixel lengths p1 _x , p2 _x , and p3 _{x in} the X direction of the monochromatic spatial light modulators 11A, 12A, and 13A are p1 _x ≧ λ _B , p2 _x ≧ λ _G , and p3 _x ≧, as in the above embodiment. It is preferably set in the range of λ _R , and the pixel lengths may be aligned and set to p1 _x = p2 _x = p3 _x = p _X ≧ λ _R.

In the spatial light modulator 10A according to this modification, similarly to the spatial light modulator 10 (see FIGS. 2 and 3), the monochromatic spatial light modulators 11A, 12A, and 13A become longer in the X direction in this order. It is formed, and both ends in the X direction are formed in a stepped shape. Further, as described above, since each of the monochromatic spatial light modulators 11A, 12A, and 13A is formed in a two-step step shape by the upper and lower magnetic thin wires 4 and 4, the total number of steps is six.

The spatial light modulator 10A according to this modification is obtained by manufacturing and superimposing the monochromatic spatial light modulators 11A, 12A, and 13A, respectively, similarly to the spatial light modulator 10. The monochromatic spatial light modulators 11A, 12A, and 13A can be manufactured in the same manner as the land and groove recording type optical magnetic recording medium. As an example, an insulating film having a thickness of h (insulating layer 64) on the substrate 6, a photolithography and etching, the width p _y, the grooves (ridges) of the half of the number of the magnetic thin wire 4 at a pitch 2p _y Form. When the magnetic film is formed from above, the upper and lower magnetic thin wires 4 are formed at the same time. Alternatively, the substrate 6 may be etched to form a groove having a depth h. The groove is formed so that the lower ground (top surface, bottom surface) of each of the upper and lower magnetic thin wires 4 is flat and smooth, and the side surface is substantially vertical, especially closer to the reverse taper so as not to adhere the magnetic film. preferable. Incidentally, it may be formed separately lower magnetic nanowire 4 and the upper magnetic nanowire 4, in this case, it is easy to form a magnetic thin wire 4 to W <p _y.

The method of setting (writing) each pixel of the monochromatic spatial light modulators 11A, 12A, and 13A of the spatial light modulator 10A in the magnetization direction based on the image data is the same as that of the above embodiment, and is a magnetic field application method. , Spin injection magnetization reversal method can be used. In the case of the magnetic field application method, the upper writing area is prevented from being applied from the magnetization means 8 for applying the magnetic field to the writing area 4w of the upper magnetic wire 4 to the lower magnetic field 4. It is preferable to provide a magnetic shield layer between the upper magnetic wire 4 and the lower magnetic wire 4 directly below and in the vicinity of 4w.

The spatial light modulator 10A according to this modification has the same optical modulation operation as the spatial light modulator 10 according to the embodiment (see FIGS. 6 and 7), and the holography apparatus 20 replaces the spatial light modulator 10. It can be used for (see FIG. 5). Here, incident on the lower part of the magnetic nanowire 4 monochromatic spatial light modulator 1A, so that the reflected light Li, Lo is not blocked in the upper part of the magnetic nanowire 4, the incident light L _W i to the spatial light modulator 10A , When incident vertically in the Y direction, that is, incident non-vertically, it is preferable to incline only in the X direction.

The spatial light modulator 10 and the spatial light modulator 10A (hereinafter collectively referred to as the spatial light modulator 10) are monochromatic spatial light modulators 11, 12, 13 (11A, 12A, 13A) with a jig as described above. When gripping and fixing, the jig may be provided with a piezoelectric actuator so that the positions of the jigs can be changed in the Y direction, or further in the X direction or the Z direction. Spatial light modulator 10, by adopting such a structure, the color image vI _B of, vI _G, it is possible to correct the deviation of the vI _R. When the structure is mechanically adjustable in the X direction, the correction can be performed without the movement of the pixel sequence in the magnetic thin wire 4 by the pulse current source 7, so that the spatial optical modulator 10 can be used for each of the magnetic thin wires 4. The position of the pixel can be fixed and set. Therefore, it is possible to form a notch (dent) or the like that traps the domain wall at the delimiter between adjacent pixels in the magnetic thin wire 4, and to accurately arrange the pixels at a preset position in the movement of the magnetic domain by the pulse current. (See Patent Document 6).

In the spatial light modulator 10, monochromatic spatial light modulators 11, 12, and 13 are superposed with the substrates 61, 62, and 63 facing downward, respectively, but they are turned upside down and the substrate 61 and the like are placed on the incident side of light. You may point it. Further, in this case, the spatial light modulator 10 is preferably formed so that the monochromatic spatial light modulators 11, 12, and 13 are shortened in the X direction in this order. In such a spatial light modulator 10, the electrodes 51, 52, and 53 are exposed on the lower side (opposite the incident side of the light), and the magnetization means 8 can be opposed to the lower side.

Further, in the spatial light modulator 10, the monochromatic spatial light modulators 11, 12, and 13 do not have to have the substrates 61, 62, and 63 on the same side above or below, respectively. For example, the first and second layer spatial light modulators 11 and 12 may be provided with the substrates 61 and 62 on the top, and the third layer spatial light modulator 13 may be provided with the substrate 63 on the bottom. In such a spatial light modulator 10, the second layer spatial light modulator 12 and the third layer spatial light modulator 13 are bonded to each other with the respective substrates 62 and 63 on the outside, and then the substrate 62 is thinned. The first layer spatial light modulator 11 is attached to the thinned substrate 62 with the substrate 61 facing upward. Before the second layer spatial light modulator 12 and the third layer spatial light modulator 13 are bonded to each other, the second layer spatial light modulator 12 puts the magnetization means 8 on the surface (on the insulating layer 64), respectively. The third layer spatial light modulator 13 is formed, and the metal pattern of the drawing wiring to be joined to the electrode 52 of the second layer spatial light modulator 12 is formed into Au, Cu, Co, Al, Ta, Ag, etc. or a multilayer thereof. It is formed of a membrane. Similarly, the second layer spatial light modulator 12 is formed with a metal pattern of the lead-out wiring to be joined to the electrode 51 on the thinned substrate 62, and the first layer spatial light modulator 11 is formed with the magnetization means 8. To.

Further, in the spatial light modulator 10, all of the monochromatic spatial light modulators 11, 12, and 13 do not have to be provided with the substrate 6. Specifically, the spatial light modulator 10 has a structure excluding the substrates 61 and 62, and has an insulating layer 64 between the magnetic thin wire 43 and the magnetic thin wire 42 and between the magnetic thin wire 42 and the magnetic thin wire 41 (interlayer), respectively. Only equipped. In such a spatial light modulator 10, first, a third layer spatial light modulator 13 is manufactured, and the insulating layer 64 on the upper surface thereof is flattened by a CMP method or the like. The magnetic thin wire 42 is formed on the flattened insulating layer 64, and the insulating layer 64 is similarly flattened to form the magnetic thin wire 41 and the insulating layer 64. After that, the insulating layers 64 at both ends in the X direction are etched stepwise to expose the electrodes 52 and 53 on the magnetic thin wires 42 and 43, and the insulating layers 64 on the writing areas 42w and 43w are thinned. Alternatively, it is turned upside down to form a magnetic thin wire 42 and a magnetic thin wire 43 on the first layer spatial light modulator 11 while forming an insulating layer 64 between them. As described above, the spatial light modulator 10 is provided with only one substrate 61 or substrate 63 on the uppermost surface or the lowermost surface, or the substrate 6 between the magnetic thin wires 41 and 42 and between the magnetic thin wires 42 and 43 is sufficiently thin. The difference in position between the hologram surfaces P1, P2, and P3 is suppressed by the conversion.

The spatial light modulator 10 is not limited to three monochromatic spatial light modulators 1, and may be provided by stacking two or four or more. Since the spatial optical modulator 10 can modulate light in a different wavelength range for each monochromatic spatial optical modulator 1, the color gamut of the image to be displayed can be increased by providing a large number of monochromatic spatial optical modulators 1. Can be done. The multi-wavelength light source device 2 includes the same number of laser light sources as the monochromatic space light modulator 1 in such a space light modulator 10, and synthesizes and irradiates light in different wavelength ranges.

The holography apparatus 20 may include two or more spatial light modulators 10 (10A) arranged in the X direction or the Y direction in order to obtain a higher definition stereoscopic image. For example, in order to reproduce an image of 8K (pixels: 7680 × 4320), the spatial light modulators 10 in which the pixels are arranged in 1920 × 1080 are arranged in 4 × 4 = 16 in the XY direction. For example, in the output optical system 3, the magnifying optics (lens) are arranged to face each other for each of the spatial light modulators 10 so that the image is not interrupted at the seam between the adjacent spatial light modulators 10 and 10. A light-shielding plate is provided so that the emitted light passing through the gaps between the light-shielding plates is enlarged and spliced into one image (see Patent Document 3).

As described above, according to the spatial light modulator according to the first embodiment of the present invention and its modification, the light is high-definition and compact, and light in a plurality of wavelength ranges is collectively incident at the same time, and each of them is individually incident. A single-plate full-color spatial light modulator that can be modulated and emitted can be configured. Then, according to the holography apparatus using the spatial light modulator, a bright full-color reproduced image can be obtained with a wide viewing angle.

[Second Embodiment]
The spatial light modulator according to the first embodiment and its modification is a display device of a holography device having a parallax in the thin line width direction of a magnetic thin line, but may also be a display device of a holography device having a parallax in the fine line direction. it can. Hereinafter, the spatial light modulator according to the second embodiment of the present invention will be described. The same elements as those in the first embodiment (see FIGS. 1 to 8) are designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIGS. 9 and 10, the spatial light modulator 10B according to the second embodiment of the present invention, like the spatial light modulator 10 according to the first embodiment (see FIG. 1), light L _W i 1st layer spatial light modulator 11B, 2nd layer spatial light modulator 12B, and 3rd layer spatial light modulator 13B (collectively, monochromatic) in order from the side to be incident (top in FIGS. 9 and 10). Spatial light modulators 11B, 12B, 13B) are stacked and provided. The spatial light modulator 10B further includes a first optical filter LF1 between the first layer spatial light modulator 11B and the second layer spatial light modulator 12B, and the second layer spatial light modulator 12B and the third layer spatial light. A second optical filter LF2 is provided between the modulators 13B. Each of the monochromatic space optical modulators 11B, 12B, and 13B has a pixel array in which pixels are two-dimensionally arranged in the horizontal (H) direction and the vertical (V) direction, and the area provided with the pixel array is the pixel area. It is referred to as IA1, IA2, IA3 (see FIG. 1). The first layer spatial light modulator 11B is reflected light L _B i of the incident light L _W i, emitted by modulated. The second layer spatial light modulator 12B is reflected light L _G i of the incident light L _W i, emitted by modulated. Then, a third layer spatial light modulator 13B is reflected light L _R i of the incident light L _W i, emitted by modulated. That is, monochromatic spatial light modulator 11B, 12B, 13B, like the monochromatic spatial light modulator 11, 12, 13 of the first embodiment, respectively, monochromatic light L _B, L _G, the spatial light modulator of L _R is there. Hereinafter, each element of the monochromatic spatial light modulators 11B, 12B, and 13B will be described.

The first layer space optical modulator 11B includes a substrate 61, a magnetic wire 41B extending in the X direction arranged side by side on the substrate 61, and an electrode 51n and an electrode 51p connected to both ends of each magnetic wire 41B. An electrode 51) and an insulating layer 64 that fills the space between the thin magnetic wires 41B and 41B are provided. The second layer space optical modulator 12B includes a substrate 62, a magnetic wire 42B extending in the X direction arranged side by side on the substrate 62, and electrodes 52n and electrodes 52p connected to both ends of each magnetic wire 42B (not shown, as appropriate). Collectively, the electrode 52) and the insulating layer 64 that fills the space between the magnetic thin wires 42B and 42B are provided. The third layer space optical modulator 13B includes a substrate 63, a magnetic wire 43B extending in the X direction arranged side by side on the substrate 63, and electrodes 53n and electrodes 53p connected to both ends of each magnetic wire 43B (not shown, as appropriate). Collectively, the electrode 53) and the insulating layer 64 that fills the space between the magnetic thin wires 43B and 43B are provided. The monochromatic spatial light modulators 11B, 12B, and 13B are provided with the same number of magnetic thin wires 41B, 42B, and 43B as the number of pixels in the Y direction of the pixel array. For example, when the number of pixels in the Y direction is 1080, each is 1080. Prepare this book. Further, in the spatial light modulator 10B, the magnetic thin wires 41B, 42B, and 43B are arranged so as to be shifted in the thin line width direction (Y direction) so as not to overlap each other in a plan view, and the monochromatic spatial light modulators 11B, 12B, and 13B are arranged. Magnetic thin wires 41B, 42B, and 43B are arranged side by side with a common pitch p _Y , respectively. In FIG. 9, for the sake of brevity, a configuration is illustrated in which eight magnetic thin wires 41B, 42B, and 43B are provided. Further, in FIGS. 9 and 10, the insulating layer 64 is transparent, and only the outline is represented by a broken line.

The monochromatic spatial light modulators 11B, 12B, and 13B have substantially the same structure except for the dimensions in a plane (pointing to the XY plane) view, and are referred to as monochromatic spatial light modulators 1B when not specified. The magnetic thin wires 41B, 42B, and 43B provided in the monochromatic spatial light modulator 1B are referred to as magnetic thin wires 4B, and the widths W1, W2, and W3 are W, and the X-direction lengths of the pixels are p1 _x , p2 _x. , P3 _x is called p _x . Similarly, the electrodes 51n, 52n and 53n are referred to as electrodes 5n, the electrodes 51p, 52p and 53p are referred to as electrodes 5p, the substrates 61, 62 and 63 are referred to as substrates 6, and the pixel regions IA1, IA2 and IA3 are referred to as pixel regions IA, respectively.

The magnetic wire 4B is a magnetic material formed in a straight line along the X direction, like the magnetic wire 4 (see FIG. 4) of the spatial light modulator 10 according to the first embodiment, and the magnetic domain is divided in the wire direction. A plurality of pixels (optical modulation elements) arranged in a row in the X direction of the pixel array are formed by generating the magnets. For example, when designing the number of pixels in the X direction to 1920, the magnetic fine wires 41B, 42B, and 43B each include 1920 pixels in the thin line direction in succession. In FIG. 10, the arrows attached to the thin magnetic wires 41B, 42B, and 43B indicate the magnetization direction, and the magnetic domains having different magnetization directions are indicated by the presence or absence of shading. The magnetic thin wire 4B includes an area constituting the plurality of pixels (referred to as a pixel array), a writing area 4w (41w, 42w, 43w) on the side connected to the electrode 5n outside the pixel array, and electrodes at both ends. It has a region connected to 5n and 5p. The magnetic thin wire 4B has a magnetic domain Dg (see FIG. 12) in a specific magnetization direction in a part of each pixel by writing, and here, in the downward magnetization direction, and of the electrode 5p in each pixel. It is provided on the side. The region of the pixel other than the magnetic domain Dg is referred to as an opening. Therefore, the magnetic thin wire 4B has a pixel divided in the thin wire direction into two magnetic domains having a magnetization direction of upward and downward, and a pixel composed of one magnetic domain having a magnetization direction of downward, and the magnetic domain having a magnetization direction of upward is In all cases, the X-direction length is the X-direction length (opening length) s _x (s1 _x , s2 _x , s3 _x ) of the opening of the pixel. With such a configuration, as will be described later, in the emitted light Lo reflected by the magnetic thin wire 4B, only the light reflected by the opening of the pixel passes through the polarizer PFo and is diffracted. The writing area 4w is set so that the length in the X direction is equal to or greater than the aperture length s _{x of the} pixel and the length in the X direction (p _{x −} s _x ) of the magnetic domain Dg or more.

The magnetic thin wire 4B is designed so that the width W is at least half the wavelength λ / 2 of the light so that the light in the wavelength range modulated by the monochromatic space optical modulator 1B shows a magneto-optical effect. Further, the magnetic wire 41B is preferably the reflected outgoing light L _B o is not substantially diffracted, Therefore, the width W1 is preferably W1 ≧ lambda _B, further to be W1 ≧ lambda _Bmax preferable. Similarly, the width W2 of the magnetic thin wire 42B is preferably W2 ≧ λ _G , and more preferably W2 ≧ λ _Gmax . The width W3 of the magnetic thin wire 43B is preferably W3 ≧ λ _R , and more preferably W3 ≧ λ _Rmax . On the other hand, the magnetic domain 4B preferably has a thickness (thickness) of about 70 nm or less and a width W of about 300 nm or less so that magnetic domains can be easily divided only in the wire direction. Further, the magnetic domain 4B has the minimum length of the magnetic domain, that is, the X-direction length s _x of the pixel opening or the X-direction length (p _x −s _x ) of the magnetic domain Dg so that the magnetic domain can be easily divided only in the wire direction. It is preferable that the width W is not too large, and specifically, the width W is preferably twice or less the minimum length. However, even if the dimensions are not such, the magnetic domain of the magnetic thin wire 4B can be in a state of being divided only in the thin wire direction by applying an external magnetic field in advance. Further, it is preferable that the adjacent magnetic thin wires 4B and 4B have a gap to the extent that they are not easily affected by the magnetization of each other. Further, the magnetic thin wire 4B preferably has a thickness of 4 nm or more, more preferably designed according to the material, in order to increase the optical rotation angle (car rotation angle) and reflect the magnetic thin wire 41B, 42B, 43B may have different thicknesses from each other.

As with the magnetic wire 4 of the first embodiment, a known ferromagnetic material, preferably a perpendicular magnetic anisotropy material, can be applied to the magnetic wire 4B, and a protective film or a base film may be provided. .. Further, in the writing region 4w, the magnetic thin wire 4B has a structure corresponding to the magnetization method (writing method) in order to change (magnetize) the desired magnetization direction by the magnetization means 8 only in this region. .. The writing method and the structure for it are as described in the first embodiment and its modification.

Further, the magnetic wire 41B is the light L _B of the first layer spatial light modulator 11B modulates, it is preferable high reflectivity and magneto-optical effect, also, in the long wavelength range than the light L _B light L _G, L is a low reflectance for _R, i.e. high transmittance or absorptivity are preferred, selecting such optical characteristics are such a material and thickness obtained. Similarly, the magnetic wire 42B is preferably highly reflective and magneto-optical effect for light L _G of the second layer spatial light modulator 12B modulates the reflectivity for light L _R of a long wavelength range than the light L _G Is preferably low. The magnetic thin wire 43B preferably has high reflectivity and magneto-optical effect for light L _R of the third layer spatial light modulator 13B modulates. The reflectance of the magnetic thin wires 41B, 42B, and 43B can be controlled not only by the material and thickness of the magnetic material alone, but also by, for example, the material of the base film, and as described in the modified example of the first embodiment. , The reflectance of light in a specific wavelength range can be increased by the dielectric multilayer film. The Kerr rotation angle of the light L _B by the magnetic wire 41B θk1, the Kerr rotation angle of the light L _G by magnetic wire 42B θk2, the Kerr rotation angle of the light L _R according to the magnetic wire 43B represents a θk3, θk1, θk2, the Shitakei3 When either is not specified, it is called a car rotation angle θk.

The electrodes 5n and 5p are connected to one end and the other end as terminals of the magnetic thin wire 4B in order to supply a current from an external power source (pulse current source 7) to the magnetic thin wire 4B in the thin wire direction. It is as described in 1 Embodiment. The substrate 6 (61, 62, 63) and the insulating layer 64 are as described in the first embodiment, respectively.

As will be described later, the spatial light modulator 10B has a pixel length p1 _x , in the order of the first layer spatial light modulator 11B, the second layer spatial light modulator 12B, and the third layer spatial light modulator 13B in the X direction. Since p2 _x and p3 _x become longer, the length in the X direction becomes longer in the order of the pixel regions IA1, IA2, and IA3. That is, the magnetic thin wires 41B, 42B, and 43B are formed so that the thin wire lengths of the pixel strings become longer in this order. Further, the second and third layer spatial light modulators 12B and 13B are extra in the X direction with respect to the pixel regions IA2 and IA3 as compared with the upper layer first and second layer spatial light modulators 11B and 12B. The spatial light modulator 10B is formed to be large, and both ends in the X direction are formed in a stepped manner. With such a structure, not only the electrodes 51 connected to both ends of the magnetic thin wire 41B of the first layer spatial light modulator 11B of the uppermost layer, but also the electrodes 52 and the third of the second layer spatial light modulator 12B below the electrodes 51. The electrode 53 of the layer-space light modulator 13B is exposed on the upper surface and can be connected to an external power source (pulse current source 7). Further, the writing area 42w of the magnetic thin wire 42B and the writing area 43w of the magnetic thin wire 43B are also arranged on the outer sides of the first and second layer spatial optical modulators 11B and 12B (boards 61 and 62) in the X direction. Since only the insulating layer 64 is provided on the upper surface, the magnetic field MF can be applied by facing the external magnetization means 8 (see FIG. 4). The first and second layer spatial light modulator 11B, 12B, the light L _R i, magnetizing means L _R o where X-direction length is input and output to the pixel region IA3 up the third layer spatial light modulator 13B The positions of the writing areas 41w and 42w and the lengths of the magnetic thin wires 41 and 42 are designed so as not to be blocked by the 8 and the electrodes 51 and 52.

Further, when the light L _G o reflected from the light L _G i and the magnetic wire 42B is incident on the magnetic thin wire 42B is transmitted through the first layer spatial light modulator 11B of the upper layer, so that unobstructed magnetic wire 41B, or so as not to undergo optical action passes through the magnetic wire 41B, the plan view of the light L _G i, L _G o of such magnetic thin wire 41B is not disposed on the optical path, the magnetic wire 41B and the magnetic wire 42B Design the positional relationship in. Similarly, the light L _R o of the optical path to the magnetic nanowire 41B reflected from the light L _R i and the magnetic wire 43B is incident on the magnetic thin wire 43B, so that 42B is not arranged, the position of the magnetic wire 41B, 42B and the magnetic wire 43B Design relationships. Specifically, the light L _G i, in the case where the incident angle in the Y direction L _R i (light L _W i) is 0 °, the magnetic wire 41B, 42B, so 43B do not overlap in plan view each other, Y Arrange them so that they are offset in the direction. Therefore, the monochromatic spatial light modulators 11B, 12B, and 13B are designed so that the magnetic thin wires 41B, 42B, and 43B are arranged side by side at a common pitch p _Y , respectively, and p _Y ≧ W1 + W2 + W3. The larger the incident angle, the wider the gap (in the Y direction) of the magnetic fine wires 41B, 42B, and 43B in the plan view, and the larger the pitch p _Y. In other words, the spatial light modulator 10B is to reduce the Y-direction length of the pixel, and in order to increase the aperture ratio, it is preferable incident angle is small in the Y direction of the incident light L _W i, 0 ° i.e. Y Most preferably, it is incident perpendicular to the direction. Further, as the outgoing light L _B o from pixel regions _{IA1, IA2, IA3, L G} o, each center of L _R o substantially matches, the first, second, third layer spatial light modulator 11B, 12B , 13B are preferably arranged and laminated, and here, they are arranged so that the centers of the pixel regions IA1, IA2, and IA3 coincide with each other in the X direction.

Next, the pixel sizes and the like of the first, second, and third layer spatial light modulators 11B, 12B, and 13B will be described in detail. The spatial light modulator 10B is a display device of a holographic apparatus, like the spatial light modulator 10 according to the first embodiment. Therefore, the first layer spatial light modulator 11B, together with the light L _B i that enters the magnetic wire 41B is optical rotation in accordance with the magnetization direction of the opening and the magnetic domain Dg of pixels, the outgoing light L _B reflected at the opening o as is transmitted through the polarizer (analyzer) PFo diffracted light, the X-direction length s1 _x, p1 _x -s1 _x of the opening and the magnetic domain Dg of pixels, based on the center wavelength lambda _B of the light L _B It is set in the range of the following equations (16) and (17). Similarly, a second layer spatial light modulator 12B is an X-direction length s2 _x, p2 _x -s2 _x of the opening and the magnetic domain Dg of pixels, the lower on the basis of the central wavelength lambda _G of the light L _G (18) , (19) is set. Then, a third layer spatial light modulator 13B is an X-direction length s3 _x, p3 _x -s3 _x of the opening and the magnetic domain Dg of pixels, the lower on the basis of the central wavelength lambda _R of the light L _R formula (20), It is set in the range of (21).
λ _B / 2 ≤ s1 _x <λ _B ... (16)
p1 _x −s1 _x ≧ λ _B / 2 ・ ・ ・ (17)
λ _G / 2 ≤ s2 _x <λ _G ... (18)
p2 _x −s2 _x ≧ λ _G / 2 ・ ・ ・ (19)
λ _R / 2 ≤ s3 _x <λ _R ... (20)
p3 _x −s3 _x ≧ λ _R / 2 ・ ・ ・ (21)

Further, in a holography apparatus using a spatial light modulator having a pixel length p, the diffraction angle φ of light having a wavelength λ emitted from a pixel is represented by the following equation (7). In the spatial light modulator 10B, monochromatic spatial light modulator 11B, 12B, 13B, as the polarizer PFo transmitted through the respective output light L _B o, L _G o, the diffraction angle of the L _R o phi match, pitch or pixel length p1 _x, p2 _x, p3 _x of the opening of the pixel, each modulated light L _B, L _G, L the center wavelength of _{R λ B, λ G,} a matching ratio lambda _R (lower Equation (22)). With such a configuration, details as described later, monochromatic spatial light modulator 11B assigned to each, 12B, effective emission light only light reflected by _{13B L B o, L G o} , as L _R o , A stereoscopic image can be formed. Therefore, the incident light L _B i, as L _G i, L white light integrally _R i L _W i, can be incident on the spatial light modulator 10B. Further, in the holography apparatus, when the pixel length p is a multiple of a half wavelength of the wavelength λ, the emitted lights of each pixel interfere with each other particularly strongly. Therefore, monochromatic spatial light modulator 11B, 12B, 13B, the light L _B, L _G, the half wavelength of L _R λ _B / 2 X direction length of the pixel p1 _x, p2 _x, p3 _x is the respective modulation, lambda It is preferably a multiple of _G / 2, λ _R / 2.
φ = sin ^-1 (λ / 2p) ・ ・ ・ (7)
p1 _x / λ _B = p2 _x / λ _G = p3 _x / λ _R ... (22)

Further, as represented by the following equation (9), the viewing angle Ψ of light having a wavelength λ in the holography apparatus becomes wider as the pixel length p is smaller (shorter). Therefore, in the spatial light modulator 10B, the smaller the pixel lengths p1 _x , p2 _x , and p3 _x , the wider the viewing angle Ψ _x (see FIG. 12) in the X direction. Although it depends on the number of pixels of the spatial optical modulator 10B and the application of the holography apparatus 20, the pixel length is such that the observer can visually recognize the entire stereoscopic image with both eyes with the X direction as the horizontal (H) direction. It is preferable that p _x is 4 times or less (Ψ _x ≧ 14.36 °) of the center wavelength λ of the incident light Li, and more preferably 2 times or less (Ψ _x ≧ 28.95 °). From equations (16) to (21), the pixel length p _x is minimized by p1 _x = λ _B , s1 _x = λ _B / 2, p2 _x = λ _G , s2 _x = λ _G / 2. , P3 _x = λ _R , s3 _x = λ _R / 2, and at this time, Ψ _x = 60 °.
Ψ = 2 sin ^-1 (λ / 2p) ・ ・ ・ (9)

The first optical filter LF1 absorbs light L _B transmits light L _G, L _R. The second optical filter LF2 transmits light L _R by absorbing light L _G. A known absorption type optical filter can be applied to the optical filters LF1 and LF2, and the optical filters are made of glass in which a light absorbing substance having wavelength selectivity is dispersed, a dielectric multilayer film, or the like. The first optical filter LF1 is arranged between the layers of magnetic thin wire 41B and the magnetic wire 42B, the magnetic wire 41B of the first layer spatial light modulator 11B, the light L _B i that is incident on the insulating layer 64 between 41B, the magnetic wire It is provided so as not to enter the 42B or the magnetic thin wire 43B. The second optical filter LF2 is placed between the layers of magnetic thin wire 42B and the magnetic wire 43B, the magnetic wire 42B of the second layer spatial light modulator 12B, the light L _G i that is incident on the insulating layer 64 between 42B, the magnetic wire It is provided so as not to enter the 43B. Accordingly, the optical filter LF1, LF2 is a plan view size and arrangement as provided in the entire optical path of the light L _W i incident on the pixel area IA3 of the third layer spatial light modulator 13B of the bottom layer. For example, if the incidence angle α is 0 ° of the incident light L _W i, the optical filter LF1, LF2 has only to overlap the entire pixel region IA3 in plan view. Spatial light modulator 10B is provided with the optical filter LF1, LF2, light L _B is the magnetic wire 42B, the 43B, the light L _G is the magnetic wire 43B, reach respectively (transmission, reflection) to to emit To prevent.

(Manufacturing method of spatial light modulator)
Similar to the spatial light modulator 10 according to the first embodiment, the spatial light modulator 10B according to the present embodiment manufactures each of the monochromatic spatial light modulators 11B, 12B, and 13B, and the optical filters LF1 and LF1 are in between. It is obtained by superimposing LF2 on both sides. Further, the first optical filter LF1 may be formed by laminating a dielectric multilayer film on the second layer spatial light modulator 12B or on the back surface of the substrate 61 of the first layer spatial light modulator 11B. The second optical filter LF2 may be formed on the third layer spatial light modulator 13B or on the back surface of the substrate 62 of the second layer spatial light modulator 12B.

[Holography equipment]
The spatial light modulator 10B according to the present embodiment can be used in the holography apparatus 20 shown in FIG. 5 in place of the spatial light modulator 10 according to the first embodiment. The holography apparatus 20 is of the horizontal parallax type, and therefore, the spatial light modulator 10B is arranged so that the X direction (the thin line directions of the magnetic thin lines 41B, 42B, 43B) displays the horizontal (H) direction. Further, if the magnetic wire 4B is made of a perpendicular magnetic anisotropy materials, the angle of incidence of the incident light L _W i to the spatial light modulator 10B α (0 ° ≦ α < 90 °) , it is alpha ≦ 30 ° Is preferable. On the other hand, when the optical filters LF1 and LF2 have an incident angle dependence, the incident angle α (> 0 °) corresponding thereto is set. As described above, in the spatial light modulator 10B, it is preferable that the light is vertically incident in the Y direction, that is, that the spatial light modulator 10B is inclined only in the X direction when it is incident non-vertically.

(How to drive the spatial light modulator)
The method of setting (writing) each pixel of the monochromatic spatial light modulators 11B, 12B, and 13B of the spatial light modulator 10B in the magnetization direction based on the image data is the same as that of the first embodiment, and a magnetic field is applied. Either the method or the spin injection magnetization reversal method can be used. However, in the present embodiment, in order to generate a magnetic domain Dg in the downward magnetization direction for each pixel, writing is performed with 2 pulses per pixel, and every other pulse, the opening of the pixel is opened based on the input signal. Write. The "dark" pixel is set in the opening in the same downward magnetization direction as the magnetic domain Dg, and the "bright" pixel is set in the opening in the upward magnetization direction. Further, the X-direction lengths of the pixel openings and the magnetic domain Dg are set by the pulse width (peak period) of the pulse current supplied by the pulse current source 7, and when the X-direction lengths are different from each other, they are alternately pulsed one by one. Change the pulse width.

(Operation of holography equipment)
Reproduction of a full-color stereoscopic image by a holographic apparatus using the spatial light modulator according to the second embodiment will be described with reference to FIGS. 11, 12, and 5 including the optical modulation operation of the spatial light modulator. .. In Figure 11, the light L _B i, L _B o, the light L _G i, L _G o, and light L _R i, L _R o is represented by the hatched or hollow arrow. In FIG. 12, for the sake of brevity, the monochromatic space optical modulator 1B shows only the pixel array portion of the magnetic thin wire 4B, and is exemplified by a configuration having eight pixels in the X direction. Also, as in FIG. 10, the magnetic thin wire is illustrated. The arrows in 4B indicate the magnetization direction, and the magnetic domains having different magnetization directions are indicated by the presence or absence of shading.

When the incident light L _W i from the multi-wavelength light source device 2 is irradiated to the spatial light modulator 10B from above, as shown in FIG. 11, is incident on the first layer spatial light modulator 11B of the top layer, the incident light L light L _B i of _W i is reflected by the magnetic wire 41B, and is emitted upward of the spatial light modulator 10B becomes outgoing light L _B o. Further, the incident light L _W i that enters the magnetic wire 41B, the insulating layer 64 between 41B is transmitted through the insulating layer 64 and the substrate 61 thereunder, and is incident on the first optical filter LF1. The first light L _B i of the incident light L _W i incident on the optical filter LF1 is absorbed by the first optical filter LF1, light L _G i, L _R i second layer spatial light of the underlying transmitted It is incident on the modulator 12B. The light L _G i is reflected by the magnetic thin wire 42B to become the emitted light L _G o and is emitted upward. Outgoing light L _G o, the first optical filter LF1 like the incident light L _G i, is emitted upward of the spatial light modulator 10B sequentially passes through the first layer spatial light modulator 11B. Further, the light L _G i, L _R i incident magnetic wire 42B, the insulating layer 64 between 42B is transmitted through the insulating layer 64 and the substrate 62 thereunder, and is incident on the second optical filter LF2. Light L _G i incident on the second optical filter LF2 is absorbed by the second optical filter LF2, the light L _R i is transmitted and enters the third layer spatial light modulator 13B underneath. The light L _R i is reflected by the magnetic thin wire 43B to become the emitted light L _R o and is emitted upward. Outgoing light L _R o, the second optical filter LF2 like the incident light L _R i, a second layer spatial light modulator 12B, a first optical filter LF1, and sequentially passes through the first layer spatial light modulator 11B space It is emitted above the light modulator 10B. On the other hand, the light L _R i incident magnetic wire 43B, the insulating layer 64 between 43B is transmitted through the insulating layer 64, it is absorbed on whether the substrate 63 is emitted from the rear surface and further transmitted through the substrate 63 underneath.

Next, the optical modulation operation of the spatial light modulator according to the present embodiment and the reproduction of a stereoscopic image of monochromatic light by the monochromatic spatial light modulator will be described with reference to FIG. The magnetic domains of the magnetic wire 4B are divided in the direction of the magnetic domain by the writing described in the driving method of the spatial light modulator, and each magnetic domain indicates an upward or downward magnetization direction. In the cross section shown in FIG. 12, magnetic domains in the downward magnetization direction are generated in the openings of the fifth and sixth pixels from the left, and magnetic domains in the upward magnetization direction are generated in the openings of the other pixels. Therefore, in the magnetic thin wire 4B, one long magnetic domain having a downward magnetization direction is generated from the region of the fourth pixel to the sixth pixel from the left, and in the other regions, the magnetization directions are short upward and downward. Magnetic domains are generated alternately. When light Li, which is one polarization component and parallel light, is incident on the monochromatic space optical modulator 1B from above, it is reflected by the magnetic thin wire 4B, and the emitted light Lo having a length W in the Y direction and a width W of the magnetic thin wire 4B is upward. Exit to. Due to the magneto-optical effect, the emitted light Lo changes the direction of polarization according to the magnetization direction in the incident region of the magnetic thin wire 4B, and rotates at an angle + θk in a magnetic domain with an upward magnetization direction and an angle −θk in a magnetic domain with a downward magnetization direction. To do. In FIG. 12, the incident light Li is represented by a linear arrow, and further, a double-headed arrow indicating the direction of polarization is attached. Further, the emitted light Lo is represented by a linear arrow emitted from each magnetic domain of the magnetic thin wire 4B, has a double-headed arrow indicating the direction of polarization, and is a polarized light rotated at an angle −θk with respect to the incident light Li. The direction is the Y direction.

Above the spatial light modulator 10B (monochromatic spatial light modulator 1B), a polarizer PFo is arranged so as to block the polarized light in the Y direction emitted from the magnetic domain Dg whose magnetization direction is downward. Therefore, as for the emitted light Lo, only the light emitted from the magnetic domain in which the magnetization direction of the pixel opening is upward passes through the polarizer PFo. Since the length s _{x in} the X direction of the upward magnetic domain is smaller than the wavelength λ, the emitted light Lo transmitted through the polarizer PFo is diffracted in the X direction and spreads to become a cylindrical wave (column surface wave) along the Y direction. .. In FIG. 12, the emitted light Lo is represented by a linear arrow diverging from the polarizer PFo and emitting. In the magnetic wire 4B, since an upward magnetic domains are arranged at several times following the pitch p _x of the wavelength of the incident light Li lambda across the downward magnetic domains Dg, light Lo that diverges polarizer PFo is by interference Strengthen each other in the same phase. In FIG. 12, the wave surface of the light in which the plurality of lights interfere is represented by a wavy line. Then, the emitted light Lo transmitted through the polarizer PFo forms an image vI of monochromatic light at a position at a predetermined distance from the emitting surface of the polarizer PFo.

As described above, in the holography apparatus 20 using the spatial light modulator 10B according to the present embodiment, the polarizer PFo forms slits having a width less than the wavelength λ of the incident light Li at a pitch of several times or less the wavelength λ. It acts as a one-dimensional diffraction grating. Since the width and pitch of the slits is dependent on the magnetic domains generated in the magnetic wire 4B, the outgoing light L _B o emitted from the spatial light modulator 10B, L _G o, for each of L _R o, one polarizer PFo the transmitted light uniform diffraction angle phi, also can be imaged each image vI _B light color, vI _G, the vI _R. Also, the exit surface of the polarizer PFo becomes a common hologram surface of the image _{vI B, vI G, vI R} . These 3 Tsunozo vI _B, vI _G, vI _R forms an image in an enlarged or reduced in the same position in the desired size and aspect ratio by enlarging optical system 31 of the output optical system 3, by mixing three-dimensional image of a full color It becomes VI. Therefore, similarly to the first embodiment, the holographic device 20, the outgoing light L _B o of the spatial light modulator _{10B, L G o, L R} o each image vI _B by, vI _G, same position vI _R, the same The image does not have to be aligned with the dimensions, and may be corrected by the magnifying optical system 31 so that the imaging position and dimensions are aligned on the output side of the output optical system 3.

In the spatial optical modulator 10B according to the present embodiment, the magnetic thin wires 41B, 42B, and 43B are arranged so as to be offset from each other in the thin line width direction, and further, between the magnetic thin wire 41B and the magnetic thin wire 42B, the magnetic thin wire 42B and the magnetic thin wire 43B the layers, by providing the optical filter LF1, LF2, respectively, the light L _B o modulated only by the magnetic wire 41B, the light L _R o which only modulated by the light L _G o and the magnetic wire 43B, modulated only by the magnetic wire 42B Can be taken out. In the case where the magnetic wire 41B for reflecting the light L _G and the light L _R, the width W1 W1 <λ _G, and more preferably designed to W1 <lambda _Gmin, light reflected by the reflected light by the magnetic wire 42B it can be weaker than the L _G o. Similarly, when the magnetic thin wire 42B reflects light L _R , the width W2 is designed to be W2 <λ _R , more preferably W2 <λ _{R min} . Alternatively, the optical path of the light L _W i incident on the magnetic thin wire 41B, the upper surface of the magnetic thin wire 41B specifically, transmits light L _B, and the light L _G, a dielectric multilayer film that absorbs L _R It may be formed. Similarly, the upper surface of the magnetic thin wire 42B, and transmits light L _G, and may be a dielectric multilayer film for absorbing light L _R.

(Modification example)
The first optical filter LF1, the magnetic thin wires 42B, may be provided is limited to the upper surface of each of 43B, the on magnetic wire 42B, a dielectric multilayer which transmits light L _G, and absorbs light L _B membrane, on magnetic wire 43B, and transmits light L _R, and a dielectric multilayer film for absorbing light L _B, are formed respectively. Further, the dielectric multilayer film on the magnetic wire 43B is a structure in which even the light L _G absorbed, may be a second optical filter LF2.

No magnetic wire 43B reflects light L _G, i.e. if the transmitted or absorbed, the spatial light modulator 10B may not be provided a second optical filter LF2. Further, if the magnetic wire 42B does not reflect light L _B, the spatial light modulator 10B is a first optical filter LF1, rather than the magnetic wire 41B, 42B layers of magnetic thin wires 42B, disposed between layers of 43B You may. Further, the magnetic wire 42B, if the 43B do not both reflect light L _B, the spatial light modulator 10B may not be provided first optical filter LF1.

Magnetic thin wire 41B is, light L _G, not to and modulated in the transmit L _R, also the magnetic wire 42B is, if transmit light L _R and is no is modulated in its spatial light modulator 10B May be arranged so that the magnetic thin wires 41B, 42B, 43B overlap each other in a plan view. With such a configuration, the Y-direction length p _Y of the pixels can be designed to be smaller than the total thin line width (W1 + W2 + W3), and high definition can be achieved in the Y direction. Further, the monochromatic spatial light modulators 11B, 12B, and 13B can be designed to have different pixel lengths p1 _y , p2 _y , and p3 _y . Further, as in the monochromatic spatial light modulator 1A (see FIG. 8) of the spatial light modulator 10A according to the modified example of the first embodiment, the magnetic thin wires 4B are arranged alternately one by one in a staggered manner. Can be done.

In the spatial optical modulator 10B, the magnetic domain Dg may be set in the upward magnetization direction. In this case, the “bright” pixel is set as the downward magnetization direction, and in the holography apparatus 20, the polarizer PFo is used. , It is arranged so as to block the light emitted from the magnetic domain whose magnetization direction is upward. The polarization direction of the outgoing light L _B o transmitted through the polarizer _{PFo, L G o, L R} o domains of magnetization directions monochromatic spatial light modulator 11B for emitting, 12B, may be different in 13B, this In this case, the single-color spatial light modulators 11B, 12B, and 13B individually set the magnetic domain Dg and the magnetization directions of the light / dark pixels. Further, the sizes of the car rotation angles θk1, θk2, and θk3 of the magnetic thin wires 41B, 42B, and 43B may be different from each other. In these cases, the outgoing light _{L B o, L G o,} L R o respectively, so that the polarization of the person who is shielded by the polarizer PFo are aligned in the same direction, the incident light L _B i, L _G i, The direction of polarization of L _R i is adjusted individually. Therefore, multi-wavelength light source device 2, provided with a polarizer PFi each laser light source 21, the light L _B before being combined by the combining optical system DP, L _G, L _R each predetermined polarization L _B i, L _G i, L _R i.

As described above, in the present embodiment, the exit surface of the polarizer PFo becomes a common hologram surface of the image _{vI B, vI G, vI R} . However, the outgoing light L _B o, L _G o, may be arranged side by side polarizer for each L _R o in the outgoing direction, the image vI _B, vI _G, by shifting the hologram surface at vI _R, the output The imaging position and dimensions can be aligned on the output side of the optical system 3. Such a polarizer has wavelength selectivity and allows light other than a specific wavelength range to be transmitted regardless of the polarization direction. Alternatively, the outgoing light L _B o, L _G o, as distinct from the polarization direction of the light shielding by L _R o, placing a polarizer in accordance with the each of the polarization directions. In this case, the polarized light to be transmitted (the light emitted from the opening of the “bright” pixel) is set so as not to be shielded by another polarizing element.

Similar to the spatial light modulator 10 according to the first embodiment, the spatial light modulator 10B according to the present embodiment may have a substrate 61 or the like overlapped with the substrate 61 or the like directed toward the incident side of light, or the substrate 61 or The structure may include only one substrate 6 of the substrate 63. Further, the spatial light modulator 10B is not limited to three monochromatic spatial light modulators 1B, and may be provided by stacking two or four or more. The holography apparatus 20 may include two or more spatial light modulators 10B arranged in the X direction or the Y direction.

As described above, according to the second embodiment of the present invention and the spatial light modulator according to the modified example thereof, as in the first embodiment, the light is high-definition and compact, and light in a plurality of wavelength ranges is collectively collected. It is possible to construct a single-plate full-color spatial light modulator that is simultaneously incident and can be individually modulated and emitted. Then, according to the holography apparatus using the spatial light modulator, a bright full-color reproduced image can be obtained with a wide viewing angle.

Although each embodiment for implementing the spatial light modulator of the present invention has been described above, the present invention is not limited to these embodiments, and various modifications can be made within the scope of the claims. Is.

10, 10A, 10B Spatial Light Modulator 11, 11A, 11B First Layer Spatial Light Modulator (Pixel Array)
12, 12A, 12B second layer spatial light modulator (pixel array)
13, 13A, 13B Third layer spatial light modulator (pixel array)
1,1A, 1B Monochromatic space optical modulator 20 Holography device 2 Multi-wavelength light source device 3 Output optical system 4,4B Magnetic wire 41,41B Magnetic wire 42,42B Magnetic wire 43,43B Magnetic wire 5n, 5p Electrode 51n, 51p Electrode 52n, 52p Electrode 53n, 53p Electrode 6 Substrate 61 Substrate 62 Substrate 63 Substrate 64 Insulation layer 7 Pulse current source 8 Magnetizing means 91 1st drive unit 92 2nd drive unit 93 3rd drive unit

Claims (10)

Light in a plurality of wavelength regions is defined as incident light, and a plurality of pixel arrays in which pixels are two-dimensionally arranged in the x direction and the y direction are provided so as to be stacked in the incident direction of the incident light, and the polarization direction of the incident light is set for each wavelength region. It is a spatial light modulator that changes to a binary angle and reflects and emits light.
In each of the pixel arrays, magnetic thin wires extending in the x direction are arranged side by side, and pixels arranged in a line in each of the magnetic thin wires are partitioned, and light in a unique wavelength region different from each other in the incident light. A spatial optical modulator characterized in that the magnetic thin wires are rotated and reflected by the magnetic thin wires, and the magnetic fine wires are arranged side by side at a pitch constant times the center wavelength of the unique wavelength region. Light in a plurality of wavelength regions is defined as incident light, and a plurality of pixel arrays in which pixels are two-dimensionally arranged in the x direction and the y direction are provided so as to be stacked in the incident direction of the incident light, and the polarization direction of the incident light is set for each wavelength region. It is a spatial light modulator that changes to a binary angle and reflects and emits light.
In each of the pixel arrays, magnetic thin wires extending in the x direction are arranged side by side, and pixels arranged in a line in each of the magnetic thin wires are partitioned, and light in a unique wavelength region different from each other in the incident light Is rotated and reflected by the magnetic wire, and the x-direction length of the pixel is a constant multiple of the center wavelength of the unique wavelength region.
The magnetic light modulator is a spatial light modulator in which each of the pixels is further divided into two in the wire direction and is rotated in a predetermined one of the binary angles in one region on the same side thereof. In each of the pixel arrays, the magnetic fine wires are arranged side by side at the same pitch.
Before and after the light in the unique wavelength region of the pixel array is incident on the magnetic wire of the pixel array and reflected, the light of the other pixel array arranged on the incident side of the incident light is applied to the magnetic wire of the other pixel array. The spatial light modulator according to claim 2, wherein the spatial light modulator is not incident. According to claim 1 or 2, the pixel array transmits light in the specific wavelength region of each of the other pixel arrays arranged on the side opposite to the incident side of the incident light. The spatial light modulator described. In the pixel array, the parallel magnetic thin wires are alternately provided with steps and arranged in a staggered manner, and the optical path length of the incident light at the steps is the center of light in the unique wavelength region of the pixel array. The spatial light modulator according to claim 4, wherein the spatial light modulator is a multiple of 1/2 of the wavelength. The spatial light modulator according to any one of claims 1 to 5, wherein the constant of the constant multiple is a multiple of 1/2. The pixel array includes a first pixel array in which the magnetic fine wire is formed of a magnetic material that rotates and reflects light in the first wavelength region of the center wavelength λ ₁ .
It is arranged to face the incident surface of the light of the first pixel array and transmits the light in the first wavelength region, and the magnetic fine wire rotates the light in the second wavelength region having the central wavelength λ ₂ . A second pixel array made of a magnetic material that reflects light
It is arranged so as to face the incident surface of the light of the second pixel array and transmits the light in the second wavelength region and the light in the first wavelength region, and the magnetic thin wire is the _third with a center wavelength λ ₃ . The spatial light modulation according to any one of claims 1 to 6, characterized in that it is a third pixel array formed of a magnetic material that rotates and reflects light in a wavelength range of 3. vessel. The pixel array according to any one of claims 1 to 7, wherein the pixel array rotates and reflects light in each wavelength range from a short wavelength to a long wavelength in the order in which the incident light is arranged from the incident side. The spatial optical modulator according to one item. An optical filter is further provided between the pixel arrays.
The optical filter absorbs or reflects light in the unique wavelength range of the pixel array facing the incident side of the incident light, and all the pixels arranged on the opposite side of the incident side of the incident light. The spatial optical modulator according to any one of claims 1 to 8, wherein the light of each of the unique wavelength regions of the array is transmitted. The spatial light modulator according to any one of claims 1 to 9.
A magnetization means for setting the magnetic fine wire of the pixel array of the spatial light modulator into a binary magnetization direction as one of the pixels.
A current supply means for supplying the magnetic thin wire with a pulse current for moving the magnetic domain generated in the magnetic thin wire in the thin wire direction.
A multi-wavelength light source that irradiates the spatial light modulator with light in a plurality of wavelength ranges,
A holographic apparatus including a polarizing filter on which light emitted from the spatial light modulator is incident.

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