JP2002357802A - Optical switching element, spatial light modulator and picture display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical switching element with a high utilization factor of light and capable of switching at a high speed, a spatial light modulator and a picture display device using it. SOLUTION: The optical switching element has a light transmission member 10 provided with a light incident plane 11, light-emitting planes 12, 13 and a total reflection surface 14 totally reflecting incident light, a reflection member (in this case, a reflection electrode 23) disposed opposite to the total reflection surface 14 of the light transmission member 10 and having at least one reflection plane fixed with at least an angle not in parallel with the total reflection surface 14 and a member 30 with a variable refractive index sandwiched between the reflection member and the light transmission member and containing a dual frequency drive liquid crystal. The refractive index of the member 30 with the variable refractive index is varied with an electric field produced between a transparent electrode 15 and the reflection electrode 23 and corresponding to the variation, the reflection plane of the incident light from the light incident plane 11 is switched either to the total reflection surface 14 or to the reflection electrode 23 so as to control the light-emitting planes of the outgoing light.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical switching element, a spatial light modulator, and an image display device. More specifically, the present invention relates to an optical switching element having high light use efficiency and capable of high-speed switching, and a spatial light modulation. The present invention relates to a container and an image display device using the same.

[0002]

2. Description of the Related Art As an optical switching element, one using liquid crystal is known, and there are a transmission type and a reflection type. In the transmission type, light that has been linearly polarized by the first polarizing plate is usually incident on the liquid crystal layer, and the orientation of liquid crystal molecules is controlled by an applied voltage to change the direction of light deflection. The light output is ON when the direction of deflection of the light transmitted through the liquid crystal is the direction transmitting the second polarizing plate, and is OFF when the light is not transmitted through the second polarizing plate. In such a configuration, two polarizing plates are required, and there is a problem that the light use efficiency is reduced. Also, in the case of the reflection type, the light use efficiency is low because the polarizing plate and the wavelength plate are combined. Further, in these systems, when the light is OFF, the light is blocked by the polarizing plate, so that there is a problem that the temperature of the polarizing plate is increased by the energy of the light.

As a technique for solving the above-mentioned problems, Japanese Patent Laid-Open No. 2000-171813 is disclosed. FIG. 29 is a diagram showing an optical switching element disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 2000-171813. FIG.
9, 101 is a light guide, 102 is a transparent electrode, 10
Reference numeral 3 denotes a liquid crystal driving IC substrate, 104 denotes an uneven structure, 105 denotes a reflective electrode, 107 and 108 denote liquid crystal molecules, and 112 denotes an electrode terminal. The orientation of the liquid crystal changes between the state shown by the liquid crystal molecules 107 and the state shown by the liquid crystal molecules 108 in FIG. 29 depending on whether or not a voltage is applied between the transparent electrode 102 and the reflective electrode 105. Which of the liquid crystal molecules 107 and 108 responds when a voltage is applied depends on the dielectric anisotropy of the liquid crystal molecules. For example, when the liquid crystal molecules 107 are oriented like the liquid crystal molecules 107, if the refractive index of the liquid crystal layer with respect to the incident light 109 becomes small, the incident light is totally reflected at the interface between the transparent electrode and the liquid crystal as shown by output light 110 in the figure.

On the other hand, if the refractive index of the liquid crystal layer with respect to the incident light 109 increases when the liquid crystal is oriented like the liquid crystal 108, the incident light passes through the liquid crystal layer and is reflected by the reflective electrode. As shown by light 111, it travels upward in FIG. Output light 110 or output light 1
When one of the lights shown in 11 is turned on, the other light is turned off.
, Thereby switching light. In Japanese Patent Application Laid-Open No. 2000-171813, light is switched by switching the direction of light. Therefore, it is possible to solve problems such as a decrease in light use efficiency and a rise in temperature of a polarizing plate, such as the above-described transmission type or reflection type. It can be done.

However, Japanese Patent Application Laid-Open No. 2000-171813 describes
According to the invention of Japanese Patent Application Laid-Open No. H11-229, a high speed light such as several tens of milliseconds when a normal nematic liquid crystal is used as a liquid crystal material, and several hundreds of microseconds even when a ferroelectric liquid crystal which is said to have a fast response speed is used. There is a problem that the switching operation cannot be performed.

The refractive index of the liquid crystal or the light guide depends on the wavelength of the incident light, and the amount of change in the refractive index varies depending on the material. It does not always change in the same way. Therefore, in the invention of Japanese Patent Application Laid-Open No. 2000-171813, as shown in FIG.
In the case where the light passes through the interface with the reflection electrode 08 and is reflected by the reflective electrode 105, the angle of refraction changes depending on the wavelength of the incident light, and as a result, the exit direction of the exit light beam changes.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, stabilizes the light emitting direction regardless of the wavelength of incident light, and performs high-speed switching with high light use efficiency. It is an object of the present invention to provide an optical switching element capable of performing the above. It is another object of the present invention to provide a spatial light modulator with high reliability and an image display device free from color misregistration by using this optical switching element.
The purpose corresponding to each claim is described below.

An object of the present invention is to provide an optical switching element having a simple structure, high durability and a high response speed. Another object of the present invention is to provide an optical switching element having a higher response speed.
A third object of the present invention is to provide an optical switching element having a high S / N ratio and high reliability.

Another object of the present invention is to provide an optical switching element having a simple structure and high S / N ratio and high reliability. A fifth object of the present invention is to provide a spatial light modulator having a high response speed. The invention of claim 6 is
It is an object of the present invention to provide a low-cost spatial light modulator with a high response speed. Another object of the present invention is to provide a low-cost and small-sized spatial light modulator in addition to the above.

An object of the present invention is to provide a low-cost image display device capable of performing high-definition display on a large screen. It is an object of the present invention to provide a low-cost image display device capable of performing high-definition display on a large screen. Another object of the present invention is to provide a low-cost and small-sized image display apparatus in addition to the above. It is an object of the present invention to provide an optical switching element in which the light emission direction is stable regardless of the wavelength of the incident light.

A further object of the present invention is to provide an optical switching element whose emission direction is stable without requiring a complicated control mechanism. A further object of the invention is to provide an optical switching element capable of controlling the emission direction to be constant regardless of the wavelength even when the environmental temperature changes. It is another object of the present invention to provide an optical switching element having a high response speed in addition to the above. It is an object of the present invention to provide a spatial light modulator in which the light emission direction is stable regardless of the wavelength of the incident light.

Another object of the present invention is to provide a low-cost spatial light modulator in addition to the above. A further object of the present invention is to provide a low-cost and small spatial light modulator in addition to the above. Claim 18
An object of the present invention is to provide a low-cost image display device capable of performing high-definition display on a large screen. It is an object of the present invention to provide a low-cost image display device capable of performing high-definition display on a large screen. In addition to the above, it is an object of the present invention to provide a low-cost and compact image display device.

[0013]

According to a first aspect of the present invention, there is provided a light guide member including a light incident surface, a light exit surface, and a total reflection surface having at least a region capable of totally reflecting incident light. , Provided to face the total reflection surface of the light guide member,
A reflecting member having at least one reflecting surface fixed at an angle which is not parallel to at least the total reflecting surface; and at least two reflecting members sandwiched between the reflecting surface and the light guide member.
A variable-refractive-index member including a frequency-driven liquid crystal.

According to a second aspect of the present invention, in the first aspect, the variable refractive index member is a liquid crystal / polymer composite in which a two-frequency driving liquid crystal is dispersed and held in a polymer matrix. Things.

A third aspect of the present invention is the liquid crystal display device according to the first or second aspect, wherein the two-frequency driving liquid crystal is oriented in a specific direction in advance.

According to a fourth aspect of the present invention, in the third aspect of the present invention, an alignment film is provided as means for previously aligning the two-frequency driving liquid crystal in a specific direction.

According to a fifth aspect of the present invention, the optical switching elements according to any one of the first to fourth aspects are arranged in a two-dimensional array.

According to a sixth aspect of the present invention, the optical switching elements according to any one of the first to fourth aspects are arranged in a one-dimensional array.

According to a seventh aspect of the present invention, in the sixth aspect of the present invention, the plane on which the optical switching elements are arranged one-dimensionally is configured to be rotatable about an axis parallel to the alignment direction of the optical switching elements. A driving means for rotating and driving the spatial light modulator is provided.

According to an eighth aspect of the present invention, there is provided a spatial light modulator according to the fifth aspect, means for causing a light beam to enter the spatial light modulator, and an image formed by the spatial light modulator is projected on a screen and displayed. And means for performing the following.

According to a ninth aspect of the present invention, there is provided a spatial light modulator according to the sixth aspect, a means for causing a light beam to enter the spatial light modulator, and a light beam emitted from the spatial light modulator. Scanning means for scanning in a direction perpendicular to the arrangement direction of the optical switching elements, and means for projecting a light beam emitted from the scanning means onto a screen for display.

According to a tenth aspect of the present invention, there is provided a spatial light modulator according to the seventh aspect, means for causing a light beam to enter the spatial light modulator, and an image formed by the spatial light modulator is projected on a screen and displayed. And means for performing the following.

According to the eleventh aspect of the present invention, there is provided a light guide member including a light incident surface, a light exit surface, and a total reflection surface having at least a region capable of totally reflecting incident light; A reflecting member that is provided to face the total reflection surface and has at least one reflection surface fixed at least at an angle that is not parallel to the total reflection surface, and is sandwiched between the reflection surface and the light guide member; An optical switching element having a variable-refractive-index member containing a liquid crystal material, characterized in that the optical switching element has means for controlling the direction of emitted light according to the wavelength of incident light.

According to a twelfth aspect of the present invention, in the eleventh aspect of the present invention, the means for controlling the direction of the outgoing light in accordance with the wavelength of the incident light includes an input angle and an incident position of the incident light to the light guide member. It has a function of adjusting according to the wavelength of light.

According to a thirteenth aspect, in the eleventh aspect, the means for controlling the direction of the outgoing light according to the wavelength of the incident light applies a bias voltage to the refractive index variable member in accordance with the wavelength of the incident light. It has the function of performing

The invention of claim 14 is the invention of claims 11 to 1
3. The liquid crystal display device according to claim 1, wherein the variable refractive index member is a liquid crystal / polymer composite in which a liquid crystal material is dispersed and held in a polymer matrix.

[0027] The invention of claim 15 is the invention of claims 11 to 1
4. The optical switching element according to any one of 4), wherein the optical switching element is arranged in a two-dimensional array.

[0028] The invention of claim 16 is the invention of claims 11 to 1
4. The optical switching element according to any one of 4), wherein the optical switching element is arranged in a one-dimensional array.

According to a seventeenth aspect, in the sixteenth aspect, a plane in which the optical switching elements are arranged one-dimensionally is configured to be rotatable around an axis parallel to the alignment direction of the optical switching elements. A driving means for rotating and driving the spatial light modulator is provided.

According to an eighteenth aspect of the present invention, there is provided the spatial light modulator according to the fifteenth aspect, means for causing a light beam to enter the spatial light modulator, and an image formed by the spatial light modulator is projected on a screen and displayed. And means for performing the following.

According to a nineteenth aspect of the present invention, there is provided a spatial light modulator according to the sixteenth aspect, means for causing a light beam to enter the spatial light modulator, and a light beam emitted from the spatial light modulator. Scanning means for scanning in a direction perpendicular to the arrangement direction of the optical switching elements, and means for projecting a light beam emitted from the scanning means onto a screen for display.

According to a twentieth aspect of the present invention, there is provided a spatial light modulator according to the seventeenth aspect, means for causing a light beam to enter the spatial light modulator, and an image formed by the spatial light modulator is projected on a screen and displayed. And means for performing the following.

[0033]

Embodiments of the present invention will be specifically described below with reference to the accompanying drawings. In all the drawings for describing the embodiments, portions having similar functions are denoted by the same reference numerals, and repeated description thereof will be omitted.

[Embodiment 1] FIG. 1 is a view for explaining a configuration example of an optical switching element according to the present invention. In the figure, reference numeral 1 denotes an optical switching element, 10 denotes a light guide member, 11 denotes an incident surface, 12 is a first exit surface, 13 is a second exit surface, 1
4 is a total reflection surface, 15 is a transparent electrode, 20 is a reflection surface, 21 is a substrate, 22 is a slope forming surface member, 23 is a reflection electrode, and 30 is a refractive index variable member (variable refractive index layer). The optical switching element 1 shown in FIG.
2, a light guide member 10 having a surface (total reflection surface) 14 having a portion (region) capable of totally reflecting incident light, and a light guide member 10 facing the total reflection surface 14 of the light guide member 10. A reflecting member (here, indicating the reflecting electrode 23) having at least one reflecting surface 20 fixed at an angle which is not parallel to the total reflecting surface;
And a variable-refractive-index member 30 including at least a dual-frequency drive liquid crystal sandwiched between the light guide member 10 and the light guide member 10.

Further, a transparent electrode 15 is provided on the total reflection surface 14 of the light guide member 10, and the reflection member 23 is formed of a metal material. The reflective electrode 23 is provided so that the refractive index of the variable member 30 can be controlled. The reflection electrode 23 may be provided separately such as a reflection member and a lower electrode.

The operation principle will be described with reference to FIG. Light from a light source (not shown) is incident on the incident surface 1 of the light guide member 10.
Light enters from 1. The incident light passes through the inside of the light guide member 10 and enters the transparent electrode 15 provided on the total reflection surface 14 of the light guide member 10. The refractive index of the transparent electrode 15 is larger than the refractive index of the light guide member 10, and light enters the transparent electrode 15. As described later, the refractive index of the refractive index variable member 30 is
The voltage applied between the transparent electrode 14 and the reflective electrode 23 is changed by an electric field generated. The refractive index of the light guide member 10 is n ₁ , the refractive index of the variable refractive index member 30 is n ₂ , and the incident angle of light from the light guide member 10 at the interface between the light guide member 10 and the transparent electrode 15 is θ _1. , Transparent electrode 15 and variable refractive index member 30
Assuming that the refractive angle of the refractive index variable member 30 at the interface with is θ ₂ , n ₁ sin θ ₁ = n ₂ sin θ ₂ regardless of the refractive index of the transparent electrode 15. The refractive index n ₂ of the refractive index variable member 30 is

[0037]

(Equation 1)

When the above condition is satisfied, the light incident from the light guide member 10 is totally reflected at the interface between the transparent electrode 15 and the refractive index variable member 30. The totally reflected light passes through the light guide member 10 and exits from the first exit surface 12 as shown in FIG. Further, the refractive index n ₂ of the refractive index variable member 30 is given by the above equation (1).
Is not satisfied, the light incident from the light guide member 10 enters the variable refractive index member 30. The light that has entered the refractive index variable member 30 is reflected by the reflective electrode 15, changes its direction, passes through the transparent electrode 15 and the light guide member 10 and changes from the second exit surface 13, as shown in FIG. Emit.

As described above, by controlling the refractive index of the refractive index variable member 30 by the voltage, for example, ON when the light is emitted from the first emission surface 12 and OFF when the light is emitted from the second emission surface 13. And vice versa, OFF when the light is emitted from the first emission surface 12, and the second emission surface 1
The light can be switched such that the light emitted from 3 is ON.

The light reflected by the reflection electrode 15 and emitted from the second emission surface 13 is reflected at the interface between the transparent electrode 15 and the variable refractive index member 30, the interface between the transparent electrode 15 and the light guide member 10, and When perpendicular to the second exit surface 13, reflection at each interface and exit surface is minimized. Therefore, it is more preferable to set the inclination α of the reflection electrode 23 as in Expression 2.

[0041]

(Equation 2)

Next, the refractive index variable member 30 will be described. The refractive index variable member 30 is configured to include at least a two-frequency driving liquid crystal. The dual-frequency drive liquid crystal is a liquid crystal having a different sign of dielectric anisotropy of the liquid crystal depending on the frequency of a voltage applied to the liquid crystal, and is characterized by a high-speed alignment operation. Dielectric anisotropy is a property in which the dielectric constant differs between the major axis direction and the minor axis direction of liquid crystal molecules. When an electric field is applied, the direction in which the dielectric constant is larger is oriented in the direction of the electric field. Since the dielectric anisotropy is positive when the dielectric constant in the major axis direction of the liquid crystal molecules is larger than the dielectric constant in the minor axis direction,
When the dielectric anisotropy is positive, the major axis of the liquid crystal molecules is oriented in the direction of the electric field, and when the dielectric anisotropy is negative, the minor axis of the liquid crystal molecules is oriented in the direction of the electric field.

FIG. 3 is a graph showing the dielectric anisotropy of the dual frequency driven liquid crystal.
It is a figure showing an example of a wave number characteristic. High frequency of applied voltage
When the frequency exceeds the crossover frequency fc, dielectric anisotropy occurs.
Sex becomes negative. For example, as shown in FIG.
Frequency f ₁When the voltage of
The liquid crystal molecules are aligned in the direction of the electric field. Long axis bending of liquid crystal
Folding rate n_//, The refractive index in the minor axis direction is n_⊥(<N_//)
And the long axis of the liquid crystal molecules is aligned with the direction of the electric field,
Has a refractive index of n_//And the refractive index in the x-axis direction and the y-axis direction
Is n_⊥Becomes Frequency f above the crossover frequency_Two
When the voltage is applied, the short axis of the liquid crystal molecules
Orientation. At this time, the direction of the liquid crystal molecules is regulated in the xy plane.
Since no controlling force acts, the major axis of the liquid crystal molecule is shown in FIG.
As shown in (B), they are oriented in random directions in the xy plane.
Therefore, the refractive index in the xy plane direction is n_⊥And n_//The average value of
And the refractive index in the z-axis direction is n_⊥Becomes

In the dual-frequency liquid crystal, whether the long axis is oriented in the direction of the electric field or the short axis is oriented in the direction of the electric field,
Since the Lorentz force acts on the liquid crystal molecules, the alignment movement is performed at a higher speed as compared with a normal liquid crystal material such as a nematic liquid crystal. Therefore, an optical switching element having a high switching speed can be manufactured.

Next, the change in the refractive index with respect to the incident light will be described. As described above, the incident light is reflected by the refractive index variable member 30.
Whether or not the light is totally reflected at the interface between the transparent electrode 15 and the transparent electrode 15 is determined by the refractive index of the refractive index variable member 30, more strictly, by the refractive index of the incident light in the electric field vector direction. The refractive index of the liquid crystal molecule can be represented by a refractive index ellipsoid E as shown in FIG. When light is incident at an incident angle β, the refractive index with respect to P-polarized light (linearly polarized light whose electric field vector is parallel to the plane of incidence) is equal to the refractive index ellipsoid E of the refractive index variable member 30 and the incident light, as shown in FIG. The refractive index with respect to the S-polarized light (linearly polarized light whose electric field vector is perpendicular to the plane of incidence) is n _P , which is parallel to the P-polarized light of the ellipse formed by crossing the vertical plane. N _S is parallel to the elliptical S-polarized light formed by the intersection of the body E and a plane perpendicular to the incident light.

The x, y, the refractive index of the z-axis direction n _x, n _y, When n _z, by applying a voltage of a frequency f _1,
When light enters when the long axis of the dual-frequency drive liquid crystal is oriented in the z-axis direction as shown in FIG. 4A, _nz =
_{n //, n x = n y} = n ⊥ , and the refractive index n _P for P-polarized light and S-polarized light, n _S is

[0047]

(Equation 3)

Is as follows. When a voltage of frequency f ₂ is applied to orient the short axis of the liquid crystal molecules in the z-axis direction, the long axis of the liquid crystal molecules is random in the xy plane, and _nz = n
_{⊥, n x = n y =} (n // + n ⊥) / 2 , and the refractive index n _P for P-polarized light and S-polarized light ', n _S' is

[0049]

(Equation 4)

Is as follows. In order for the light emission direction to be switched between the first emission surface and the second emission surface when the frequency of the drive voltage is switched between f ₁ and f ₂ or between f ₂ and f ₁ , the refractive index of the light guide member is required. For n ₁ , (n _P > n ₁ , n _P ′ <n ₁ ) (5) and / or (n _S <n ₁ , n _S ′> n ₁ ) (6) I just need. When the incident light is P-polarized light, the above equation (5) is used.
Is satisfied, and in the case of S-polarized light, the above expression (6) may be satisfied. As long as the expressions (5) and (6) are satisfied, any polarization direction can be used.

When a voltage is applied to the transparent electrode and the lower electrode of this device at a frequency f ₁ lower than the crossover frequency fc, for example, when P-polarized light is incident as shown in FIG. The refractive index of the variable-refractive-index member 30 for P-polarized light is larger than the refractive index of the light-guiding member 10, and the incident light is transmitted through the variable-refractive-index member 30 without being totally reflected and reflected by the reflecting member. The light exits from the second exit surface 13. Also, when driving at a frequency f ₂ higher than fc, P
When polarized light is incident, the refractive index of the refractive index variable member 30 with respect to the P-polarized light is smaller than the refractive index of the light guide member 10, and is totally reflected at the interface between the transparent electrode 15 and the refractive index variable member 30. The light exits from the first exit surface. Since the change in the refractive index is reversed for S-polarized light, it is opposite to the case where the exit surface is P-polarized light.

As the two-frequency driving liquid crystal, for example,
-Dicyano-4-pentyloxyphenyl-4- (trans-4-ethylcyclohexyl) benzoate, 2,
3-dicyano-4pentyloxyphenyl-trans-
4-propyl-1-cyclohexanecarboxylate,
2,3-dicyano-4-ethoxyphenyl-4- (trans-4-pentylcyclohexyl) benzoate,
2,3-dicyano-4-ethoxyphenyl-4- (trans-4-butylcyclohexyl) benzoate,
3-dicyano-4-butoxyphenyl-4- (trans-4-butylcyclohexyl) benzoate and the like can be used.

The light guide member 10 is made of glass, plastic, or crystal having high transmittance for incident light. It is desirable to use an isotropic material having a small variation in the internal refractive index. Specific examples of the glass include flint glass, heavy flint glass, crown glass, heavy crown glass, light crown glass, borosilicate glass, quartz glass, and the like, and plastics such as polycarbonate, polymethyl acrylate, and polymethacrylic acid. Methyl and the like. As a manufacturing method, a general method such as a molding method using a mold or a shaping method using polishing can be used.

The slope forming member 22 can be formed by a method using a silicon process, a method of molding a thermosetting or thermoplastic resin with a mold, or the like.
The reflective electrode 23 is formed on the surface of the slope forming member 22 by a material such as aluminum having high reflectivity and good conductivity by sputtering, vapor deposition, or the like.

When a drive circuit or the like is incorporated in the substrate 21, it is necessary to provide a contact hole in the slope forming member 22 by etching or the like, and to electrically connect the reflective electrode 23 and the substrate 21.

FIG. 6 is a view for schematically explaining another example of the configuration of the optical switching element according to the present invention, and the reflection member is omitted. The orientation control is performed in advance so that the major axis of the dual-frequency driving liquid crystal 31 included in the refractive index variable member 30 is oriented in a direction perpendicular to the incident surface 11 when no electric field is applied. invention).

For example, it is assumed that the long axis of the two-frequency driving liquid crystal 31 having a positive dielectric anisotropy has been subjected to an alignment process in advance so as to be aligned in the x-axis direction in the xy plane. When a voltage is applied at the crossover frequency below the frequency f _1, two long axis of frequency driving liquid crystal 31, as in FIG. 6 (A), for orienting in the direction of the electric field, the refractive index in the z-axis direction is n _z = n _//, the refractive index of the x-axis and y-axis direction is _{n x = n y = n ⊥} . At this time, the refractive indexes n _P and n _S for P-polarized light and S-polarized light are

[0058]

(Equation 5)

Is as follows. This is the same as equation (3). When a voltage is applied in a cross-over frequency or higher frequency f _2, the long axis of the dual frequency addressable liquid crystal 31 is aligned in the direction parallel to the vertical direction, ie, the total reflection surface 14 on the field, the total reflection surface 14 by alignment treatment Since the liquid crystal 31 is oriented in the x-axis direction in a parallel plane, the dual-frequency drive liquid crystal 31 is oriented in the x-axis direction as a result. Therefore, _nz = _ny = n _// and _nx = n _} . In this case, the refractive index n _P ″ for P-polarized light and S-polarized light
And n _S "is,

[0060]

(Equation 6)

Is obtained. In order to switch the light emission direction between the first emission surface 12 and the second emission surface 13 when the frequency of the drive voltage is switched between f ₁ and f ₂ or between f ₂ and f ₁ , the light guide member 10 relative refractive index n _{1 of, (n P> n 1,} n P "<n 1) ··· (9) and / _{or, (n S <n 1,} n S"> n 1) ··· (10) When the incident light is P-polarized light, equation (9) may be satisfied, and when the incident light is S-polarized light, equation (10) may be satisfied. As long as the expressions (9) and (10) are satisfied, any polarization direction can be used.

When comparing equation (8) with equation (4), n _P ′ <
n _P is a _{", n S '<n S} ". That is, when the orientation treatment is performed in a direction perpendicular to the incident surface 11, the amount of change in the refractive index increases. Therefore, it is possible to increase the difference in refractive index upon application of a voltage of a frequency f ₁ and frequency f _2, it is possible to increase the margin of the incident angle β with respect to the light switching operation. That is, a margin for the error of the parallelism and the incident angle of the incident light is increased, and the incident angle β itself can be reduced.

FIG. 7 is a diagram showing still another configuration example of the optical switching element according to the present invention. The configuration of this embodiment is
The present invention is characterized in that alignment films 16 and 25 are provided as means for aligning the major axis direction of liquid crystal molecules in advance (the invention of claim 4). As a method of forming the alignment films 16 and 25, a rubbing method in which the surface of the organic polymer film is rubbed several times with a cotton cloth or a brush in a direction in which the long axis of the liquid crystal molecules is desired to be aligned (rubbing treatment); Various existing methods can be used, such as a method of forming a grating by an oblique evaporation method in which evaporation is performed obliquely, an etching method, or the like. Alignment film 1
Reference numerals 6 and 25 are provided on the surface sandwiching the refractive index variable member 30, that is, the outermost surface of the total reflection surface 14 of the light guide member 10 and the outermost surface of the reflection member.

A description will be given of still another configuration example of the present invention. The optical switching element of this configuration has the same configuration as that of FIG. 2, but the refractive index variable member 30 is a liquid crystal / polymer composite in which a two-frequency driving liquid crystal material is dispersed and held in a polymer matrix. (The invention of claim 2). Examples of such a structure include a structure in which fine capsules containing a liquid crystal material covered with a polymer film are bonded using a binder resin, or a mixture of a liquid crystal material and a polymer material (or a precursor thereof). Phase-separated,
There is a so-called polymer dispersed liquid crystal. Hereinafter, a polymer-dispersed liquid crystal will be described in more detail as an example.

The polymer matrix material is preferably a polymer transparent to incident light, and may be any of a thermoplastic resin, a thermosetting resin, and a photocurable resin. The polymer-dispersed liquid crystal is produced by (1) a polymer phase separation method in which a solution is formed from the liquid crystal and a thermosetting or photocurable (polymerizable) monomer or oligomer and phase separation is performed by polymerization; A solvent evaporation phase separation method in which a solution is formed and the solvent is evaporated to cause phase separation, and (3) a thermal phase separation method in which a liquid crystal and a thermoplastic polymer are heated and dissolved and then phase separated by cooling can be used. .

As the polymer, it is preferable to use a UV-curable resin from the viewpoint of easiness in the production process, separation from the liquid crystal phase, and the like. As a specific example, an ultraviolet curable acrylic resin is exemplified, and a resin containing an acrylic monomer or acrylic oligomer which is polymerized and cured by irradiation with ultraviolet light is particularly preferable. Examples of such a monomer or oligomer include (poly) ester acrylate, (poly) urethane acrylate, epoxy acrylate, polybutadiene acrylate, silicone acrylate, melamine acrylate, and (poly) phosphazene methacrylate. As another example, a thiol-ene system can be suitably used because of its high photocuring speed.

A photopolymerization initiator may be used in order to carry out the polymerization promptly. Examples thereof include acetophenones such as dichloroacetophenone and trichloroacetophenone;
Hydroxycyclohexyl phenyl ketone, benzophenone, Michler's ketone, benzoyl, benzoin alkyl ether, benzyldimethyl ketal, monosulfide, thioxanthones, azo compounds, diallyliodonium salts, triallylsulfonium salts, bis (trichloromethyl) triazine compounds and the like. Can be.

A liquid material in which a liquid crystal material is uniformly dissolved in the ultraviolet curable compound is used as a reflection member (here, the reflection electrode 2).
After the light is injected between 3) and the light guide member 10, the ultraviolet curable compound is cured by irradiating ultraviolet rays, and at the same time, the liquid crystal material is phase-separated to form a polymer dispersed liquid crystal layer.

In the case of this configuration, as a method of pre-aligning the liquid crystal in order to increase the amount of change in the refractive index, in addition to using the method of forming the alignment films 16 and 25 as described in the configuration of FIG. Alternatively, the following method can be used.

When polymerizing the polymer matrix of the variable-refractive-index member 30, an electric field is applied to the variable-refractive-index member 30, whereby the liquid crystal can be oriented in one direction. At this time, the polymer matrix material in contact with the liquid crystal is aligned in the same direction by being dragged by the alignment of the liquid crystal. When the polymer matrix material is polymerized in this state, the interface with the liquid crystal is fixed in a form following the orientation of the liquid crystal. Since this interface structure functions as an alignment film for the liquid crystal, even if the electric field is released after the polymer matrix material is cured, the liquid crystal aligns with the direction of the electric field applied during polymerization.

FIG. 8 is a diagram schematically showing the structure of the refractive index variable member 30 and a configuration in which a reflecting member and the like are omitted for the purpose of explaining the operation. The refractive index variable member 30 has a structure in which a two-frequency driving liquid crystal having a fine particle diameter is dispersed and held in an ultraviolet curable resin. When the ultraviolet curable resin is cured, an electrostatic field is applied in the x-axis direction in the drawing by means (not shown). The two-frequency drive liquid crystal is applied and the long axis is oriented in the x-axis direction and cured. The transparent electrode 15 and the lower electrode 23 'of this device
For dual frequency addressable liquid crystal molecules as shown in FIG. 8 (A) in the case of applying a voltage at a low frequency f ₁ than crossover frequency fc is oriented in the z-axis direction, P-polarized light as shown in FIG example Is incident, the P of the refractive index variable member 30
The refractive index for the polarized light is larger than the refractive index of the light guide member 10, and the incident light passes through the refractive index variable member 30 without being totally reflected, is reflected by a reflection member (not shown), and is reflected from the second emission surface. Emit.

On the other hand, the above-mentioned element is operated at a frequency f higher than fc.
When driven at _2, as shown in FIG. 8 (B), the long axis of the liquid crystal molecules are oriented in the x-axis direction in the figure, for example, the refractive index light-guiding member 10 of the refractive index variable member 30 with respect to P-polarized light Electrode 15 and the refractive index variable member 3
The light is totally reflected at the interface with 0 and exits from the first exit surface 12. Since the change in the refractive index is reversed for s-polarized light, it is reversed for the case where the exit surface is p-polarized. In FIG. 8A, the refractive index variable member 30 is hardly scattered.
In order to allow the liquid crystal to pass through the inside, the particle diameter of the liquid crystal droplet is preferably ５ of the wavelength of the incident light, more preferably 1/10 or less. It has been experimentally found that the response speed becomes extremely high when the liquid crystal becomes such a minute droplet, so that an optical switching element having a higher response speed can be formed.

FIG. 9 is a view for explaining still another example of the configuration of the present invention (the invention of claim 6). FIG. 9A is a schematic perspective view of an optical switching element, and FIG. 9B is a schematic cross-sectional view of the optical switching element of FIG. 9A, and FIG. 9C is a schematic cross-sectional view of the same in the y-direction. In the configuration of this configuration example, the reflection members and the reflection electrodes as individual electrodes are arranged in a one-dimensional direction, and the refractive index variable member 30 is sandwiched between the light guide member 10 and the reflection electrode 23. A transparent electrode 15 is provided on the total reflection surface of the light guide member 10 as a common electrode. It is preferable that the substrate 21 is connected to the reflection electrode 23 which is an individual electrode, and a driving element for selectively supplying a signal to the reflection electrode 23 is provided. By selectively applying a voltage signal to each individual electrode (reflecting electrode 23) arranged in an array, the refractive index of the refractive index variable member 30 is spatially modulated, and ON / OFF of linear light (spatial light modulation) is performed. ) Can be. Also, two-dimensional spatial light modulation can be performed by combining with a scanning device that scans in a direction perpendicular to the direction in which the individual electrodes are arranged.

FIG. 10 is a schematic diagram schematically showing an example of the configuration of an image display device using the spatial light modulator according to the present invention. In FIG. 10, reference numeral 40 denotes a spatial light modulator, and 41 denotes a light source. , 42 are a collimating lens, 43 is a scanning mechanism, 44 is a projection lens, 45 is a screen, and 46 is two-dimensional spatial modulation data. In this configuration example, the driving of the individual reflection electrodes of the spatial light modulator 40 and the driving of the scanning device are controlled by an image signal, and the obtained two-dimensional spatial light-modulated light beam is projected on a screen to thereby display the image display device. Can be formed (the invention of claim 9). In FIG. 10, the spatial light modulator 40
The outgoing light totally reflected by the total reflection surface and emitted from the first emission surface is projected as ON, but the light reflected by the reflection member and emitted from the second emission surface is projected as ON. May be.

FIG. 11 is a diagram for explaining another configuration example of the image display device according to the present invention. As shown in FIG. 11, the one-dimensional spatial light modulator 40 itself includes a scanning mechanism 4.
7 and scanning in a direction perpendicular to the direction in which the reflection members are arranged, a more compact two-dimensional spatial light modulator can be formed (the invention of claim 7).

FIG. 12 is a diagram for explaining still another example of the configuration of the image display device according to the present invention. In this configuration example, the scanning mechanism 47 is attached to the one-dimensional spatial light modulator 40 itself.
Is provided, and scanning is performed in a direction perpendicular to the direction in which the reflecting members are arranged, whereby a compact image display device can be provided (the invention of claim 10). In the case of the two-dimensional system by scanning the one-dimensional spatial light modulator 40, the incident angle of the light beam from the light source 41 to the spatial light modulator 40 changes according to the scanning. Does function as an optical switching element if the total reflection condition (Equation 1) is satisfied even if the incident angle changes. 9, 10, and 1.
In the configuration examples of FIGS. 1 and 12, the one-dimensional array of light guide members 10 is shared and one light guide member 10 is used.
May be divided for each optical switching element. The scanning mechanisms 43 and 47 can use an existing method such as a galvano method using Lorentz force, a method using electrostatic force, and a method using electrostriction or magnetostriction.

FIG. 13 is a schematic perspective view for explaining another configuration example of the spatial light modulator according to the present invention. FIG.
As shown in FIG. 3, the reflection member (here, the reflection electrode 23) is
By arranging them in a dimensional array, a two-dimensional spatial light modulator can be formed (the invention of claim 5). In this case, since two-dimensional spatial light modulation can be performed only by the spatial light modulator, the scanning mechanisms 43 and 4 as in the configuration examples of FIGS.
The image display device can be formed without providing the image display device 7 (the invention of claim 8). It should be noted that in FIG.
Are common, but the light guide member 10 may be divided for each optical switching element.

In an image display apparatus using the above-described one-dimensional array spatial light modulator or two-dimensional array spatial light modulator, incident light of a plurality of wavelengths such as red, green, and blue is used, and time division is performed. A full-color image can be displayed by displaying an image of each color (field sequential method) or by providing a plurality of spatial light modulators and projecting the images of each color simultaneously.

An example in which the optical switch element according to the first embodiment of the present invention as described above is embodied will be described below. (Embodiment 1) FIG. 14 is a view for explaining an example of a manufacturing process of an optical switching element. (A) Production of reflection control member As shown in FIG.
A driving element 26 of OSFET is formed, and a CV
An oxide film 27 of silicon oxide having a thickness of 5 μm was deposited by Method D. Next, the inclined surface w and the contact hole 24 were formed by performing patterning using a photomask on which an area gradation pattern was formed and performing dry etching. After filling the hole by metal CVD, aluminum was deposited to a thickness of 0.1 μm by sputtering.
The reflection control member 28 was obtained by patterning so as to be a reflection member and a lower electrode (reflection electrode 23).

(B) Cell Production As shown in FIG. 14B, flint glass (F2,
n = 1.615 at 633 nm)
0 transparent electrode 1 made of 50 nm thick ITO on the total reflection surface
5 and the reflection control member 28 obtained in FIG. 14A were bonded together using a sealing material 29 made of an epoxy resin, thereby producing an empty cell. An injection hole (not shown) was provided in a part of the sealing material.

(C) Injection As shown in FIG. 14 (C), the inside of the empty cell obtained in FIG. 14 (B) was evacuated, and then the dual-frequency driving liquid crystal (MQ001543, manufactured by Merck Ltd.) was placed in the empty cell. _n⊥ = no = 1.4
978, n _// = ne = 1.7192, Δn = 0.221
The variable refractive index member 30 according to 4) was injected, and the injection hole was sealed. Laser light (wavelength: 670 nm) is incident as P-polarized light from the incident surface onto the optical switching element thus manufactured, and a peak value of 20 V is applied between the transparent electrode and the lower electrode.
Was applied. When the frequency of the applied rectangular wave was switched between 1 kHz and 100 kHz, the light emitted from the first emission surface 12 could be switched at high speed in accordance with the applied frequency.

(Example 2) FIG. 15 is a view for explaining another example of the manufacturing process of the optical switching element. (A) Production of reflection control member As shown in FIG.
A plurality of driving elements 26 formed by OSFETs were formed one-dimensionally, and an oxide film 27 of silicon oxide having a thickness of 5 μm was deposited thereon by CVD. Next, the inclined surface w and the contact hole 24 were formed by performing patterning using a photomask on which an area gradation pattern was formed and performing dry etching. Then, after filling the holes by metal CVD, aluminum was deposited to a thickness of 0.1 μm by sputtering, and patterning was performed so as to be a reflecting member and a lower electrode (reflecting electrode 23). A polyimide precursor is coated on the surface of the reflecting member and the lower electrode, patterned by a photolithography method using a striped photomask, heated at 250 ° C. and imidized to form a grating with a pitch of 1 μm and an average depth of 0.5 μm. An oriented film was formed by forming the polyimide film thus obtained.

(B) Cell Production As shown in FIG. 15B, flint glass (F2,
n = 1.615 at 633 nm)
0 transparent electrode 1 made of 50 nm thick ITO on the total reflection surface
5 is further coated with a polyimide precursor, patterned by a photolithography method using a striped photomask, and then heated at 250 ° C. to imidize to form a grating with a pitch of 1 μm and an average depth of 0.5 μm. An alignment cell 16 formed by forming the polyimide film thus obtained and the reflection control member 28 shown in FIG. 15A were bonded together by using a sealing material 29 made of an epoxy resin to produce an empty cell. An injection hole (not shown) was provided in a part of the sealing material 29.

[0084] (C) in as shown in infusion diagram 15 (C), FIG. 15 after evacuating the inside air cells (B), dual frequency addressable liquid crystal (manufactured by Merck & Co. in the air cell, MX001543, n _⊥ = no = 1.4978,
n _// = ne = 1.7192, Δn = 0.2214), and the injection hole was sealed.

Laser light (wavelength 670 nm) is incident on the optical switching element manufactured as described above as P-polarized light from the incident surface, and is interposed between the transparent electrode 15 and the lower electrode (reflective electrode 23) which is an individual electrode. A unipolar rectangular wave having a peak value of 20 V was applied. When the frequency of the applied rectangular wave was selectively switched between 1 kHz and 100 kHz, the light emitted from the second emission surface could be spatially modulated at high speed in accordance with the applied frequency.

(Embodiment 3) FIG. 16 is a view for explaining another example of the manufacturing process of the optical switching element. (A) Production of reflection control member As shown in FIG.
A plurality of drive elements 26 formed of SFETs were formed two-dimensionally, and a 5 μm thick silicon oxide was deposited thereon by a CVD method to form an oxide film 27. Next, the inclined surface w and the contact hole 24 were formed by performing patterning using a photomask on which an area gradation pattern was formed and performing dry etching. After filling the hole by metal CVD, aluminum was sputtered to 0.1.
Deposited in a thickness of μm, and a reflection member and lower electrode (reflection electrode 23)
Patterned so that

(B) Cell Production As shown in FIG. 16B, flint glass (F2, n
= 1.615 at 633 nm)
Transparent electrode 15 made of 50 nm thick ITO on the total reflection surface of
And the reflection control member of FIG. 16A are bonded together using a sealing material 29 made of epoxy resin.
An empty cell was prepared. An injection hole (not shown) was provided in a part of the sealing material 29.

(C) Injection As shown in FIG. 16B, after evacuating the inside of the empty cell, a two-frequency driving liquid crystal (MX00154 manufactured by Merck & Co., Ltd.) is used.
_{3, n ⊥ = no = 1.4978} , n // = ne = 1.719
2, Δn = 0.2214) and an ultraviolet curable compound (NO
A mixture (liquid crystal concentration: 40% by weight) of a mixture of NOA81 (manufactured by RAND, acrylic monomer) was injected, and the injection hole was sealed.

(D) Curing As shown in FIG. 16 (D), while applying an electrostatic field in a direction perpendicular to the plane of FIG.
V light (50 mW / cm ² ) was applied to form a polymer dispersed liquid crystal.

Laser light (wavelength: 670 nm) is incident as P-polarized light from the incident surface on the optical switching element thus manufactured, and a wave is generated between the transparent electrode 15 and the lower electrode (reflective electrode 23) which is an individual electrode. A unipolar rectangular wave having a high value of 20 V was applied. Selectively change the frequency of the applied rectangular wave to 1
By switching between kHz and 100 kHz, the light emitted from the second emission surface could be spatially modulated at high speed in accordance with the applied frequency, and an image could be displayed on the screen using the projection lens.

[Second Embodiment] The present invention is characterized in that the direction of outgoing light is controlled according to the wavelength of incident light (claim 11). As a method of controlling the direction of the emitted light according to the wavelength, a deflecting means for deflecting the direction of the emitted light according to the wavelength is provided. The direction of the emitted light is controlled by controlling the incident angle according to the wavelength of the incident light. Or controlling the refractive index according to the wavelength of the incident light so that the emission direction is constant. This makes it possible to make the direction of the emitted light constant regardless of the wavelength of the incident light.

FIG. 17 is a diagram for explaining the function of the optical switching element according to the present invention, in which drive elements and the like that are unnecessary for the description are omitted. In the optical switching element having this configuration, the wavelength λ of the incident light from the light source 41 is λ1>λ2>.
When there are three types of light sources of λ3, the incident position and the incident angle of the incident light incident on the light guide member 10 from each light source are changed according to the wavelength so that the position and the direction of the emitted light become the same. Thus, the direction of the outgoing light can be made constant regardless of the wavelength of the incident light with a simple configuration.

FIG. 18 is a diagram showing still another configuration example of the optical switching element of the present invention. The light switching element shown in FIG. 18 includes a light guide member 10 including a light incident surface 11, a light exit surface 12, and a surface having a portion capable of totally reflecting incident light (a total reflection surface 14); A reflecting member (here, a reflecting electrode 23) that is provided to face the total reflection surface 14 of the light guide member 10 and includes at least one reflection surface fixed at least at an angle that is not parallel to the total reflection surface.
And a variable-refractive-index member 30 containing a liquid crystal material sandwiched between the light-guiding member 10 and the reflecting member having the reflecting surface. Further, a transparent electrode 15 is provided on the total reflection surface of the light guide member 10.
The reflective member is formed of a metal material, and the reflective electrode 23 is controlled so that the refractive index of the refractive index variable member 30 can be controlled by applying a voltage between the reflective member and the transparent electrode 15.
And The reflection electrode 23 may be provided separately such as a reflection member and a lower electrode.

The operating principle will be described with reference to FIG. Light from a light source (not shown) is incident on the light incident surface 1 of the light guide member 10.
Light enters from 1. The incident light passes through the inside of the light guide member 10 and enters the transparent electrode 15 provided on the total reflection surface 14 of the light guide member 10. The refractive index of the transparent electrode 15 is larger than the refractive index of the light guide member 10, and light enters the transparent electrode 15. As described later, the refractive index of the refractive index variable member 30 is
The voltage changes between the transparent electrode 15 and the reflective electrode 23 due to the electric field generated. The refractive index of the light guide member 10 is n ₁ , the refractive index of the variable refractive index member 30 is n ₂ , and the incident angle of light from the light guide member 10 at the interface between the light guide member 10 and the transparent electrode 15 is θ _1. , Transparent electrode 15 and variable refractive index member 30
Assuming that the refraction angle of the refractive index variable member 30 at the interface with is θ ₂ , n ₁ sin θ ₁ = n ₂ sin θ ₂ (11) regardless of the refractive index of the transparent electrode 15.

The refractive index n ₂ of the refractive index variable member 30 is

[0096]

(Equation 7)

When the above condition is satisfied, the light incident from the light guide member 10 is totally reflected at the interface between the transparent electrode 15 and the refractive index variable member 30. The totally reflected light passes through the light guide member 10 and exits from the first exit surface 12 as shown in FIG. If the refractive index n ₂ of the variable refractive index member 30 does not satisfy the above expression (11), the light incident from the light guide member 10 enters the variable refractive index member 30. Light incident on the refractive index variable member 30 is reflected by the reflective electrode 23,
As shown in FIG. 19B, the light passes through the transparent electrode 15 and the light guide member 10 while changing its direction, and exits from the second exit surface 13.

As described above, by controlling the refractive index of the refractive index variable member 30 with the voltage, it is possible to switch the light from the second emission surface 13 which is the output light.
Although it is possible to use the light from the first exit surface 12 as output light, even if the light is turned off, a slight reflection component is output, so that the S / N ratio deteriorates. Only light from the second exit surface 13 is used as output light.

The output light reflected by the reflection electrode 23 and emitted from the second emission surface 13 is reflected at the interface between the transparent electrode 15 and the refractive index variable member 30 and between the transparent electrode 15 and the light guide member 1.
When it is perpendicular to the interface with 0 and the second exit surface 13, the reflection at each interface and the exit surface is minimized. Therefore, it is more preferable to set the inclination angle α of the reflection electrode as shown in Expression (12).

[0100]

(Equation 8)

The refractive index of the variable refractive index member 30 depends on the wavelength of the incident light, and the rate of change and the amount of change vary depending on the material. For example, the light guide member 10 and the variable refractive index Does not necessarily change in the same way. Therefore, even if light is incident at a constant incident angle, the refraction angle changes depending on the wavelength, and as a result, the emission direction changes depending on the wavelength. Therefore, in the present invention, as shown in FIG. 18, a constant bias voltage is applied according to the wavelength of the incident light, in addition to the drive voltage generator 51 that changes the refractive index of the liquid crystal by applying a voltage to the reflective electrode 23. Voltage generator 52 is provided for controlling the refractive index of the refractive index variable member 30 by superimposing a bias voltage in accordance with the wavelength of the incident light source so as to make the angle of the emitted light constant.

For example, the refractive index variable member 30 for setting the light emission direction to the direction shown in FIG. 19B regardless of the wavelength of the incident light.
And the change in the refractive index due to the signal from the drive voltage generator 51 when the wavelength of the incident light is λ is n2.
Assuming that (λ) ′, when a light having a wavelength λ is incident, a bias voltage that gives a change in refractive index corresponding to δn (λ) = na−n2 (λ) ′ (14) is applied. become. As described above, according to the thirteenth aspect, by changing the applied bias voltage, it is possible to keep the direction of the outgoing light constant for incident light of any wavelength. Further, even when the refractive index characteristic changes due to a change in the environmental temperature, it is possible to flexibly cope with the adjustment of the bias voltage.

FIG. 20 is a view for explaining still another configuration example of the optical switching element of the present invention, wherein the variable refractive index member 30 is a liquid crystal / polymer composite. Invention). Examples of such a structure include a structure in which fine capsules containing a liquid crystal material covered with a polymer film are bonded using a binder resin, or a mixture of a liquid crystal material and a polymer material (or a precursor thereof). There is a so-called polymer-dispersed liquid crystal obtained by phase separation.
Hereinafter, a polymer-dispersed liquid crystal will be described in more detail by way of example.

As the liquid crystal material, a nematic liquid crystal, a smectic liquid crystal, a cholesteric liquid crystal, or the like can be used. A single or two or more liquid crystal compounds or a mixture containing a substance other than the liquid crystal compound may be used. As the polymer matrix material, a polymer transparent to incident light is preferable, and any of a thermoplastic resin, a thermosetting resin, and a photocurable resin may be used. The polymer-dispersed liquid crystal is produced by (1) a polymer phase separation method in which a solution is formed from the liquid crystal and a thermosetting or photocurable (polymerizable) monomer or oligomer and the phases are separated by polymerization; (2) a liquid crystal, a polymer and a solvent are used. A solvent evaporation phase separation method in which a solution is formed and the solvent is evaporated to cause phase separation, and (3) a thermal phase separation method in which a liquid crystal and a thermoplastic polymer are heated and dissolved and then phase separated by cooling can be used. .

As the polymer, it is preferable to use a UV-curable resin from the viewpoint of easiness in the production process, separation from the liquid crystal phase, and the like. As a specific example, an ultraviolet curable acrylic resin is exemplified, and a resin containing an acrylic monomer or acrylic oligomer which is polymerized and cured by irradiation with ultraviolet light is particularly preferable. Examples of such a monomer or oligomer include (poly) ester acrylate, (poly) urethane acrylate, epoxy acrylate, polybutadiene acrylate, silicone acrylate, melamine acrylate, and (poly) phosphazene methacrylate. As another example, a thiol-ene system can be suitably used because of its high photocuring speed.

Further, a photopolymerization initiator may be used in order to quickly carry out the polymerization. Examples thereof include acetophenones such as dichloroacetophenone and trichloroacetophenone, 1-hydroxycyclohexylphenyl ketone, benzophenone, Michler's ketone, benzoyl and benzoinalkyl. Examples include ether, benzyldimethyl ketal, monosulfide, thioxanthones, azo compounds, diallyliodonium salts, triallylsulfonium salts, and bis (trichloromethyl) triazine compounds.

A liquid material in which a liquid crystal material is uniformly dissolved in the above-mentioned ultraviolet-curable compound is injected between the reflecting member and the light-guiding member, and then the ultraviolet-curable compound is cured by performing ultraviolet irradiation. At the same time, the liquid crystal material is phase separated,
A polymer dispersed liquid crystal layer is formed.

The operation of the above configuration will be described. FIG. 21 is a schematic diagram for explaining the operation in the embodiment shown in FIG. 20, and in the figure, 32 is a liquid crystal droplet constituting the refractive index variable member 30. Transparent electrode 15 and lower electrode 23 '
21A, when no voltage is applied between
As shown in (1), the liquid crystal molecules in the liquid crystal droplet 32 are oriented in different directions, and as a result, are optically isotropic. When a voltage is applied between the electrodes, FIG.
As shown in (B), the major axis or minor axis of the liquid crystal molecules in the droplet is oriented in the direction of the electric field. Whether the major axis or the minor axis of the liquid crystal molecules is oriented in the direction of the electric field depends on the dielectric anisotropy of the liquid crystal molecules. The dielectric anisotropy is positive (the dielectric constant in the major axis direction is larger than the dielectric constant in the minor axis direction). In the case of (large), the major axis is oriented in the direction of the electric field, and when the dielectric anisotropy is negative (the permittivity in the minor axis is larger than the permittivity in the major axis), the minor axis is oriented in the direction of the electric field. I do. If the refractive index of the refractive index variable member 30 changes depending on the orientation of the liquid crystal, and, for example, P-polarized light (the direction of the electric field vector is parallel to the incident surface) is incident, a voltage is applied between the electrodes (the transparent electrode 15 and the lower electrode 23 '). Is not applied, the transparent electrode 15 is applied as shown in FIG.
The light is totally reflected at the interface between the light emitting element and the refractive index variable member 30 and exits from the first exit surface 12. Further, when a voltage is applied between the above-mentioned electrodes, as shown in FIG. 21B, incident light is transmitted through the variable refractive index member 30 without being totally reflected and reflected by a reflecting member (not shown). The light exits from the second exit surface 13.

In FIG. 21B, in order for the incident light to pass through the variable refractive index member 30 without being scattered, the particle size of the liquid crystal droplet 32 should be 1/5 of the wavelength of the incident light. It is better to be less than or equal to 1/10 or less. It has been experimentally found that the response speed becomes extremely high when the liquid crystal becomes such a minute droplet, so that an optical switching element having a higher response speed can be formed.

FIG. 22 is a view for explaining still another configuration example (the invention of claim 16) of the optical switching element of the present invention. FIG. 22 (A) is a schematic perspective view of the optical switching element.
FIG. 22B is a schematic cross-sectional view of the optical switching element of FIG. 22A in the x direction, and FIG.
This is shown in FIG. As shown in FIG. 22A, the reflection member and the reflection electrode 23 as an individual electrode are arranged in a one-dimensional direction, and the variable refractive index member 30 is sandwiched between the light guide member 10 and the reflection electrode 23. I have. A transparent electrode 15 is provided on the total reflection surface of the light guide member 10 as a common electrode. It is preferable that the substrate 21 is connected to the reflection electrode 23 which is an individual electrode, and a driving element for selectively supplying a signal to the reflection electrode 23 is provided. By selectively applying a voltage signal to each of the individual electrodes arranged in an array, the refractive index of the refractive index variable member is spatially modulated, thereby turning on the linear light.
/ OFF (spatial light modulation). Also, two-dimensional spatial light modulation can be performed by combining with a scanning device that scans in a direction perpendicular to the direction in which the individual electrodes are arranged.

As shown in FIG. 23, the spatial light modulator 4
Driving and scanning device for individual reflection electrodes of 0 (scanning mechanism 43)
Is controlled by an image signal, and the obtained two-dimensionally spatially modulated light beam (two-dimensionally spatially modulated data 46) is projected on a screen 45 to form an image display device. invention). In FIG. 23, the light emitted from the first emission surface 12 is totally reflected and projected as ON, but the light reflected by the reflecting member and emitted from the second emission surface 13 is projected as ON. Is also good.

As shown in FIG. 24, the one-dimensional spatial light modulator 4
A more compact two-dimensional spatial light modulator can be formed by providing the scanning mechanism 47 on the zero itself and scanning in a direction perpendicular to the direction in which the reflecting members are arranged (the invention of claim 17). . Further, as shown in FIG. 25, by providing a scanning mechanism 47 in the one-dimensional spatial light modulator itself and scanning in a direction perpendicular to the direction in which the reflecting members are arranged,
A compact image display device can be provided (the invention of claim 20). In the case of the two-dimensional system by scanning the one-dimensional spatial light modulator 40 as described above, the incident angle of the light beam from the light source 41 to the spatial light modulator 40 changes according to the scanning. In the present invention, the optical switching element functions as long as the total reflection condition (Equation 11) is satisfied even when the incident angle changes. In addition, FIG. 22, FIG. 23, FIG.
5 is a single one-dimensional array of light guide members 10, but the light guide member 10 may be divided for each optical switching element. As the scanning mechanism, an existing method such as a galvano method using Lorentz force, a method using electrostatic force, a method using electrostriction or magnetostriction can be used.

As shown in FIG. 26, a two-dimensional spatial light modulator can be formed by arranging the reflecting members (here, the reflecting electrodes 23) in a two-dimensional array.
Invention). In this case, since two-dimensional spatial light modulation can be performed only by the spatial light modulator, an image display device can be formed without providing a scanning mechanism as shown in FIGS. 10 and 12 (the invention of claim 18). In FIG. 13, the light guide member is shared by one, but the light guide member may be divided for each optical switching element.

In the image display device using the one-dimensional array spatial light modulator or the two-dimensional array spatial light modulator, incident light of a plurality of wavelengths such as red, green, and blue is used, and time division is performed. A full-color image can be displayed by displaying an image of each color (field sequential method) or by providing a plurality of spatial light modulators and projecting the images of each color simultaneously.

An example in which the optical switch element according to the second embodiment of the present invention is embodied will be described below.

(Example 2-1) FIG. 27 is a view for explaining an example of a manufacturing process of an optical switching element according to the present invention. (A) Production of Reflective Electrode As shown in FIG.
A drive element is formed by T, and 5
An oxide film 27 was formed by depositing silicon oxide having a thickness of μm. Next, patterning was performed using a photomask on which an area gradation pattern was formed, and dry etching was performed to form an inclined surface w having an inclination angle of 32 ° and a contact hole 24. Then, after filling the holes by metal CVD, aluminum was deposited to a thickness of 0.1 μm by sputtering, and patterning was performed so as to become a reflecting member and a lower electrode (reflecting electrode 23). A polyimide precursor is coated on the surface of the reflecting member and the lower electrode, patterned by a photolithography method using a striped photomask, and then heated at 250 ° C. to imidize to form a grating with a pitch of 1 μm and an average depth of 0.5 μm. The polyimide film thus formed was formed as an alignment film 25b.

(B) Cell Production As shown in FIG. 27B, flint glass (F2, λ
= 635 nm, n = 1.615, λ = 488 nm, n =
1.632) (a structure in which the angle between the incident surface 11 and the total reflection surface 14 is 70 ° and the total reflection surface 14 and the second emission surface 13 are parallel) 50 nm on the total reflection surface of the light guide member 10 After forming a transparent electrode 15 made of thick ITO, further applying a polyimide precursor and patterning it by a photolithography method using a stripe-shaped photomask, 25
Heat at 0 ° C. to imidize, pitch 1 μm average depth 0.1
An alignment cell 25a formed by forming a polyimide film having a 5 μm grating formed thereon and the reflective electrode 23 of FIG. 27A were bonded together using a sealing material 29 made of an epoxy resin, thereby producing an empty cell. An injection hole (not shown) was provided in a part of the sealing material 29.

(C) Injection As shown in FIG. 27 (C), after evacuating the empty cell in FIG. 27 (B), the nematic liquid crystal (λ = 635 nm, n
o = 1.49, ne = 1.69, λ = 488 nm and no =
1.49, ne = 1.72) and the injection hole was sealed.

Laser light of three wavelengths (R: 635 nm,
G: 532 nm, B: 488 nm) was incident on the incident surface 11 as P-polarized light. At this time, the incident angle of the laser beam on the incident surface 11 of the light guide member 10 is 0 for the R laser beam.
The laser beams were arranged so as to be 0.5 ° for the laser beam of G, 0.5 ° for the laser beam of G, and 2.2 ° for the laser beam of B.

When each laser beam is sequentially incident on the incident surface 11 of the light guide member 10 in a state where no voltage is applied between the transparent electrode 15 and the reflective electrode 23, the laser light is applied to the total reflection surface 14 of the light guide member 10. , And was emitted from the first emission surface 12. Next, while applying a voltage of 20 V between the transparent electrode 15 and the reflective electrode 23, each laser beam is applied to the incident surface 1 of the light guide member 10.
1 are sequentially incident, each laser beam is refracted into the refractive index variable member 30 and is reflected by the
Out of the light exit surface 13. At this time, the emission angle of each laser beam is perpendicular to the total reflection surface 14 and the second emission surface 13, so that the interface between the refractive index variable member 30 and the light guide member 10 and the light guide member 10 The reflection at the interface with air could be minimized. As described above, light could be switched without bending the emission direction regardless of the wavelength of the incident light.

Example 2-2 A drive voltage generator 51 and a bias voltage generator 52 were connected to the optical switching element manufactured in Example 2-1 as shown in FIG. The same R, G, and B lasers as in Example 2-1 were sequentially incident on the incident surface of the light guide member 10 at an incident angle of 0 °. When no voltage is applied between the transparent electrode 15 and the reflective electrode 23, all of the R, G, and B laser beams are totally reflected by the total reflection surface 14 of the light guide member 10 and are reflected from the first emission surface 12. Emitted. A voltage of 20 V is applied between the transparent electrode 15 and the reflective electrode 23, no bias voltage is applied when the incident light is R, and -3 V when the incident light is G.
, And in the case of B, a bias voltage of -5 V was superimposed. At this time, each laser beam was refracted into the refractive index variable member 30, reflected by the reflection electrode 23, and emitted from the second emission surface 13. The emission angle of each laser beam is the total reflection surface 1
4 and the second exit surface 13 were perpendicular to each other, and were the same for each laser beam. Therefore, the refractive index variable member 3
The reflection at the interface between the light guide member 10 and the light guide member 10 and the interface between the light guide member 10 and the air could be minimized. As mentioned above,
The light could be switched without bending the emission direction regardless of the wavelength of the incident light.

(Example 2-3) FIG. 28 is a view for explaining another example of the process of producing the optical switching element according to the present invention. (A) Production of Reflective Electrode As shown in FIG.
A plurality of SFET-based driving elements 26 were formed two-dimensionally, and 5 μm thick silicon oxide was deposited thereon by CVD. Next, patterning was performed using a photomask on which an area gradation pattern was formed, and dry etching was performed to form an inclined surface w having an inclination angle of 32 ° and a contact hole 24. After filling the hole by metal CVD, aluminum was sputtered to 0.1μ.
It was deposited to a thickness of m and patterned so as to serve as a reflection member and a lower electrode.

(B) Cell Production As shown in FIG. 28B, flint glass (F2, λ
= 635 nm, n = 1.615, λ = 488 nm, n =
1.632) (a structure in which the angle between the incident surface 11 and the total reflection surface 14 is 70 ° and the total reflection surface 14 and the second emission surface 13 are parallel to each other) 10 50 nm
An empty cell was produced by laminating a transparent electrode 15 formed of thick ITO and the reflective electrode portion prepared in (A) above using a sealing material 29 made of epoxy resin. An injection hole (not shown) was provided in a part of the sealing material 29.

(C) Injection As shown in FIG. 28 (C), after evacuating the empty cell of (B), the nematic liquid crystal (n = λ = 635 nm)
o = 1.49, ne = 1.69, λ = 488 nm and no =
1.49, ne = 1.72) and an ultraviolet curable compound (NO
A mixture (liquid crystal concentration: 30 wt%) 30 ′ of NOA81 (acrylic monomer, manufactured by RLAND) was injected, and the injection hole was sealed.

(D) Curing As shown in FIG. 28 (D), UV light (50 mW) was applied by a high-pressure mercury lamp while applying an electrostatic field in a direction perpendicular to the paper surface.
/ Cm ² ) to form a polymer-dispersed liquid crystal, whereby a refractive index variable member 30 was obtained.

The laser light having three wavelengths (R: 635 nm,
G: 532 nm, B: 488 nm) was incident on the incident surface 11 as P-polarized light. At this time, the incident angle of the laser beam on the incident surface 11 of the light guide member 10 was set to 0 ° for each of the R, G, and B laser beams. R, G, B when no voltage is applied between the transparent electrode 15 and the reflective electrode 23
All the laser beams were totally reflected by the total reflection surface 14 of the light guide member 10 and emitted from the first emission surface 12. Next, the transparent electrode 15
A voltage of 20 V was applied between the reflective electrode 23 and the reflective electrode 23. When the incident light was R, no bias voltage was applied. At this time, each laser beam is refracted into the refractive index variable member 30 and is reflected by the reflection electrode 23 so that the second emission surface 13
Emitted. The emission angle of each laser beam was perpendicular to the total reflection surface 14 and the second emission surface 13, and the emission direction was the same for each laser beam. Therefore, reflection at the interface between the refractive index variable member 30 and the light guide member 10 and at the interface between the light guide member 10 and air could be minimized. As described above, light could be switched without bending the emission direction regardless of the wavelength of the incident light.

(Example 2-4) An optical switching element in which the reflection electrodes 23 are two-dimensionally arranged was produced by the production method shown in Example 2-1. The light of the halogen lamp was collimated, separated by a dichroic filter, separated into R, G, and B, and shaped into the size of the incident surface 11 of the optical switching element, and irradiated sequentially. At this time, a signal corresponding to the image information is applied to the individual reflective electrode according to the wavelength of the incident light, and further, according to the R, G, and B of the incident light as described in Embodiment 2-2. Bias voltage was superimposed. An image could be displayed by projecting the signal light output from the second exit surface 13 onto a screen through a projection lens. The obtained image was a good full-color image with no deviation of the R, G, and B images.

[0128]

According to the first aspect of the present invention, there is provided a light guide member including a light incident surface, a light exit surface, and a surface having a portion capable of totally reflecting incident light (total reflection surface); A reflecting member that is provided to face the total reflection surface of the light guide member, and that includes at least one reflection surface that is fixed at least at an angle that is not parallel to the total reflection surface; and between the reflection surface and the light guide member In addition, since the refractive index variable member including at least the two-frequency driving liquid crystal is sandwiched, an optical switching element having a simple structure, high durability, and high response speed can be provided.

Effect of the second aspect of the invention: In the first aspect of the invention, since the variable-refractive-index member is a liquid crystal / polymer composite in which a dual-frequency driving liquid crystal material is dispersed and held in a polymer matrix, the response is further improved. An optical switching element having a high speed can be provided.

Effect of the invention of claim 3: claim 1 or 2
According to the invention, since the two-frequency driving liquid crystal is oriented in a specific direction in advance, an optical switching element having a high S / N ratio and high reliability can be provided.

Effect of the invention of claim 4 In the invention of claim 3, since an alignment film is provided as a means for previously aligning the dual frequency driving liquid crystal in a specific direction, the S / N ratio and the reliability are simple. Optical switching element having a high density can be provided.

Effect of the invention of claim 5: claims 1 to 4
Since the optical switching elements according to any one of the above are arranged in a two-dimensional array, a spatial light modulator having a high response speed can be provided.

Advantages of the invention of claim 6: claims 1 to 4
Since the optical switching elements according to any one of the above are arranged in a one-dimensional array, a spatial light modulator having a high response speed and a low cost can be provided.

According to the seventh aspect of the present invention, the plane in which the optical switching elements are arranged one-dimensionally is provided rotatably about an axis parallel to the alignment direction of the optical switching elements. Since the device and the driving mechanism for rotating and driving the spatial light modulator are provided, it is possible to provide a small spatial light modulator having a high response speed, a low cost, and a low cost.

According to the eighth aspect of the present invention, there is provided a spatial light modulator according to the fifth aspect, means for causing a light beam to enter the spatial light modulator, and an image formed by the spatial light modulator is projected onto a screen. Since the display device includes a display unit, a low-cost image display device capable of performing high-definition display on a large screen can be provided.

According to the ninth aspect of the present invention, there is provided a spatial light modulator according to the sixth aspect, means for causing a light beam to enter the spatial light modulator, and a light beam emitted from the spatial light modulator being subjected to the spatial light modulation. Since it has a scanning mechanism for scanning in a direction perpendicular to the alignment direction of the optical switching elements of the device, and means for projecting and displaying light beams emitted from the scanning mechanism on a screen, high-definition display can be performed on a large screen. And an inexpensive image display device.

According to the tenth aspect of the present invention, the spatial light modulator according to the seventh aspect, means for causing a light beam to enter the spatial light modulator, and an image formed by the spatial light modulator is projected on a screen. Display means, high-definition display can be performed on a large screen, and a low-cost and small-sized image display device can be provided.

According to the eleventh aspect of the present invention, there is provided a light guide member including a light incident surface, a light exit surface, and a surface having a portion capable of totally reflecting incident light (total reflection surface); A reflecting member that is provided to face the total reflection surface of the light member, and includes at least one reflection surface fixed at an angle that is not parallel to at least the total reflection surface, and between the reflection surface and the light guide member. In an optical switching element that holds a refractive index variable member including a liquid crystal material, the direction of emitted light is controlled in accordance with the wavelength of incident light, so that the light emitting direction is stable regardless of the wavelength of incident light. A switching element can be provided.

According to the twelfth aspect, in the eleventh aspect, the means for controlling the direction of the outgoing light according to the wavelength of the incident light includes the incident angle and the incident position of the incident light to the light guide member. Since the adjustment is performed in accordance with the wavelength of light, an optical switching element whose emission direction is stable can be provided without requiring a complicated control mechanism.

According to the thirteenth aspect, in the eleventh aspect, a bias voltage is applied to the variable-refractive-index member according to the wavelength of the incident light as means for controlling the direction of the outgoing light according to the wavelength of the incident light. Therefore, it is possible to provide an optical switching element capable of controlling the emission direction to be constant regardless of the wavelength even when the environmental temperature changes.

Effect of the invention of claim 14: In any one of the inventions of claims 11 to 13, the variable refractive index member is a liquid crystal / polymer composite in which a liquid crystal material is dispersed and held in a polymer matrix. In addition to the above, an optical switching element having a high response speed can be provided.

According to the fifteenth aspect of the present invention, since the optical switching elements according to any one of the eleventh to fourteenth aspects are arranged in a two-dimensional array, the light emission direction can be changed regardless of the wavelength of the incident light. A stable spatial light modulator can be provided.

According to the sixteenth aspect, since the optical switching elements according to any one of the eleventh to fourteenth aspects are arranged in a one-dimensional array, in addition to the above, a low-cost spatial light modulator can be provided. Can be provided.

According to the seventeenth aspect of the present invention, the spatial light according to the sixteenth aspect, wherein the plane on which the optical switching elements are arranged one-dimensionally is provided rotatably about an axis parallel to the alignment direction of the optical switching elements. Since the modulator and the driving mechanism for driving the spatial light modulator to rotate are provided, it is possible to provide a small spatial light modulator with a high response speed, a low cost, and a low cost.

According to the eighteenth aspect of the present invention, the spatial light modulator according to the fifteenth aspect, means for causing a light beam to enter the spatial light modulator, and an image formed by the spatial light modulator is projected onto a screen. Since the display device includes a display unit, a low-cost image display device capable of performing high-definition display on a large screen can be provided.

According to the nineteenth aspect of the present invention, the spatial light modulator according to the sixteenth aspect, means for making a light beam incident on the spatial light modulator, and a light beam emitted from the spatial light modulator being subjected to the spatial light modulation Since it has a scanning mechanism for scanning in a direction perpendicular to the alignment direction of the optical switching elements of the device, and means for projecting and displaying light beams emitted from the scanning mechanism on a screen, high-definition display can be performed on a large screen. And an inexpensive image display device.

According to the twentieth aspect, the spatial light modulator according to the seventeenth aspect, means for causing a light beam to enter the spatial light modulator, and an image formed by the spatial light modulator is projected onto a screen. Display means, high-definition display can be performed on a large screen, and a low-cost and small-sized image display device can be provided.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration example of an optical switching element according to the present invention.

FIG. 2 is a diagram for explaining an operation principle of the optical switching element shown in FIG.

FIG. 3 is a diagram illustrating an example of a frequency characteristic of dielectric anisotropy of a two-frequency driving liquid crystal.

FIG. 4 is a diagram for explaining a change in alignment of liquid crystal molecules according to an applied voltage.

FIG. 5 is a diagram for explaining the action of liquid crystal molecules by an index ellipsoid.

FIG. 6 is a diagram schematically illustrating another configuration example of the optical switching element according to the present invention.

FIG. 7 is a diagram showing still another configuration example of the optical switching element according to the present invention.

FIG. 8 is a diagram schematically illustrating a structure of a variable refractive index member and a configuration in which a reflection member and the like are omitted for the purpose of describing the operation thereof.

FIG. 9 shows still another configuration example of the present invention (the invention of claim 6).
FIG.

FIG. 10 is a schematic diagram schematically illustrating an example of a configuration example of an image display device configured using the spatial light modulator according to the present invention.

FIG. 11 is a diagram for explaining another configuration example of the image display device according to the present invention.

FIG. 12 is a diagram for explaining still another configuration example of the image display device according to the present invention.

FIG. 13 is a schematic perspective view illustrating another configuration example of the spatial light modulator according to the present invention.

FIG. 14 is a diagram illustrating an example of a manufacturing process of an optical switching element.

FIG. 15 is a diagram for explaining another example of the manufacturing process of the optical switching element.

FIG. 16 is a diagram for explaining another example of the manufacturing process of the optical switching element.

FIG. 17 is a diagram for explaining a function of the optical switching element according to the present invention.

FIG. 18 is a diagram showing still another configuration example of the optical switching element of the present invention.

FIG. 19 is a diagram for explaining an operation example of the optical switching element according to the present invention.

FIG. 20 is a diagram for explaining still another configuration example of the optical switching element of the present invention.

FIG. 21 is a schematic diagram for explaining the operation in the embodiment shown in FIG. 20;

FIG. 22 is a diagram for explaining still another configuration example (the invention of claim 16) of the optical switching element of the present invention.

FIG. 23 is a schematic diagram schematically illustrating an example of a configuration example of an image display device configured using the spatial light modulator according to the present invention.

FIG. 24 is a diagram for explaining another configuration example of the image display device according to the present invention.

FIG. 25 is a diagram for explaining still another configuration example of the image display device according to the present invention.

FIG. 26 is a schematic perspective view illustrating another configuration example of the spatial light modulator according to the present invention.

FIG. 27 is a diagram for explaining an example of a manufacturing process of the optical switching element according to the present invention.

FIG. 28 is a diagram for explaining another example of the manufacturing process of the optical switching element according to the present invention.

FIG. 29 is a diagram showing an optical switching element disclosed in Japanese Patent Application Laid-Open No. 2000-171813.

FIG. 30 is a diagram for describing a problem in the configuration of JP-A-2000-171813.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Optical switching element, 10 ... Light guide member, 11 ... Incident surface, 12 ... 1st emission surface, 13 ... 2nd emission surface, 14 ...
Total reflection surface, 15 ... Transparent electrode, 16, 25, 25a, 25
b: alignment film, 20: reflection surface, 21: substrate, 22: slope forming surface member, 23: reflection electrode, 23 ': lower electrode, 24 ...
Contact hole, 26: drive element, 27: oxide film, 2
8: Reflection control member, 29: Seal member, 30: Variable refractive index member (variable refractive index layer), 31: Dual frequency drive liquid crystal, 32
... liquid crystal droplet, 40 ... spatial light modulator, 41 ... light source, 42 ... collimating lens, 43 ... scanning mechanism, 44 ...
Projection lens, 45 screen, 46 two-dimensional spatial modulation data, 47 scanning mechanism, 51 driving voltage generator, 5
2. Bias voltage generator, 101 light guide, 102
Transparent electrode, 103: IC substrate for driving liquid crystal, 104: uneven structure, 105: reflective electrode, 107, 108: liquid crystal molecules,
109 ... incident light, 110 ... output light, 111 ... output light, 1
12 ... electrode terminals.

Continued on the front page F term (reference) 2H088 EA40 GA10 HA03 HA06 HA21 HA30 2H089 HA04 TA04 TA07 TA17 TA20 2H090 JA03 KA11 LA20 MA06 2H093 NA17 NB29 NE04 NE06 NF11

Claims (20)

[Claims] 1. A light guide member comprising: a light incident surface, a light exit surface, and a total reflection surface having at least a region capable of totally reflecting incident light; A reflecting member having at least one reflecting surface fixed to an angle that is not parallel to at least the total reflecting surface, and at least two reflecting members sandwiched between the reflecting surface and the light guide member; An optical switching element comprising: a refractive index variable member including a frequency-driven liquid crystal. 2. The optical switching element according to claim 1, wherein the variable refractive index member is a liquid crystal / polymer composite in which a two-frequency driving liquid crystal is dispersed and held in a polymer matrix. Switching element. 3. The optical switching device according to claim 1, wherein the two-frequency driving liquid crystal is oriented in a specific direction in advance. 4. The optical switching element according to claim 3, wherein an alignment film is provided as means for previously aligning the two-frequency driven liquid crystal in a specific direction. 5. A spatial light modulator, wherein the optical switching elements according to claim 1 are arranged in a two-dimensional array. 6. A spatial light modulator, wherein the optical switching elements according to claim 1 are arranged in a one-dimensional array. 7. The spatial light modulator according to claim 6, wherein a plane on which the optical switching elements are arranged one-dimensionally is configured to be rotatable about an axis parallel to an alignment direction of the optical switching elements. A spatial light modulator comprising a driving means for rotating and driving the spatial light modulator. 8. A spatial light modulator according to claim 5, comprising: means for causing a light beam to enter the spatial light modulator; and means for projecting and displaying an image formed by the spatial light modulator on a screen. An image display device characterized by the above-mentioned. 9. The spatial light modulator according to claim 6, means for causing a light beam to enter the spatial light modulator, and a light beam emitted from the spatial light modulator to an optical switching element of the spatial light modulator. An image display device comprising: a scanning unit that scans in a direction perpendicular to an alignment direction; and a unit that projects a light beam emitted from the scanning unit onto a screen and displays the screen. 10. A spatial light modulator according to claim 7, comprising means for causing a light beam to enter the spatial light modulator, and means for projecting and displaying an image formed by the spatial light modulator on a screen. An image display device characterized by the above-mentioned. 11. A light guide member comprising a light incident surface, a light exit surface, and a total reflection surface having at least a region capable of totally reflecting incident light, and opposing the total reflection surface of the light guide member. A reflecting member having at least one reflecting surface fixed at an angle that is not parallel to at least the total reflecting surface, and a liquid crystal material sandwiched between the reflecting surface and the light guide member. An optical switching element having a variable refractive index member including: means for controlling an outgoing light direction according to the wavelength of incident light. 12. The optical switching device according to claim 11, wherein the means for controlling the direction of the outgoing light according to the wavelength of the incident light determines the incident angle and the incident position of the incident light on the light guide member. An optical switching element having a function of adjusting the wavelength according to the wavelength. 13. The optical switching element according to claim 11, wherein the means for controlling the direction of the emitted light according to the wavelength of the incident light applies a bias voltage to the refractive index variable member according to the wavelength of the incident light. An optical switching element having a function. 14. The optical switching element according to claim 11, wherein the variable refractive index member is a liquid crystal / polymer composite in which a liquid crystal material is dispersed and held in a polymer matrix. Characteristic optical switching element. 15. A spatial light modulator, wherein the optical switching elements according to claim 11 are arranged in a two-dimensional array. 16. A spatial light modulator, wherein the optical switching elements according to claim 11 are arranged in a one-dimensional array. 17. The spatial light modulator according to claim 16, wherein a plane in which the optical switching elements are one-dimensionally arranged is:
A spatial light modulator characterized by being rotatable about an axis parallel to the direction in which the optical switching elements are arranged, and having driving means for rotationally driving the spatial light modulator. 18. The spatial light modulator according to claim 15,
An image display apparatus comprising: means for causing a light beam to enter the spatial light modulator; and means for projecting and displaying an image formed by the spatial light modulator on a screen. 19. The spatial light modulator according to claim 16,
Means for causing a light beam to enter the spatial light modulator; scanning means for scanning a light beam emitted from the spatial light modulator in a direction perpendicular to an alignment direction of optical switching elements of the spatial light modulator; Means for projecting a light beam emitted from the means on a screen for display. 20. The spatial light modulator according to claim 17,
An image display apparatus comprising: means for causing a light beam to enter the spatial light modulator; and means for projecting and displaying an image formed by the spatial light modulator on a screen.