JP2007065543A - Variable optical element and optical device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a variable optical element in which optical characteristics of the variable optical element can be locally changed into a desired pattern without decreasing the quantity of transmitting light in the variable optical element, and to provide an optical device using the variable optical element. <P>SOLUTION: The variable optical element using a semiconductor nano-crystal is characterized in that a current is locally applied to the semiconductor nano-crystal to change the refractive index and thereby, to locally modulate a phase of light transmitting the semiconductor nano-crystal. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a variable optical element capable of changing optical characteristics, and further relates to an optical device using the variable optical element.

Conventionally, a liquid crystal variable hologram element 50 shown in FIG. 5 using a polymer-dispersed liquid crystal or a polymer-stabilized liquid crystal is known as a variable optical element capable of changing optical characteristics (see Patent Document 1). In the liquid crystal variable hologram element 50, polymer layers 58 and liquid crystal layers 59 are alternately arranged between transparent substrates 56 and 57 at intervals of about the wavelength of light used. In the liquid crystal layer 59, for example, nematic liquid crystal grains 55 are arranged, and polymer dispersed liquid crystals in which the grains 55 are separated by a polymer are used. Alternatively, the liquid crystal layer 59 may be a polymer-stabilized liquid crystal in which liquid crystal molecules 53 are separated by a polymer wall or network.
As another variable optical element, a programmable mask that electrically controls light transmittance by a two-dimensional shutter array has been proposed for transferring a programmable pattern by photolithography (see Patent Document 2).
JP 2001-209037 A Special Table 2002-511980

However, in the optical device using the variable optical element using the liquid crystal described in Patent Document 1, the variable optical element is not controlled by multiple channels, and the optical element can be controlled in a desired pattern. There was a problem that I could not.
Further, the invention described in Patent Document 2 is a control of light transmittance by a shutter, and is a variable optical element that simply controls transmission and non-transmission of light, and there is a problem that its application is limited. there were.
In these conventional patent documents, nothing is described regarding changing the refractive index of the transparent region of the variable optical element.

  The present invention has been made in view of the above problems, and an object of the present invention is to locally change the optical characteristics of the variable optical element in a desired pattern without reducing the amount of transmitted light of the variable optical element. It is to provide a variable optical element capable of achieving the above. Furthermore, the present invention provides an optical device using the variable optical element.

  The invention of claim 1 is a variable optical element using a semiconductor nanocrystal, wherein the refractive index of the semiconductor nanocrystal is changed.

  According to a second aspect of the present invention, in the variable optical element according to the first aspect, a current is passed through the semiconductor nanocrystal to change a refractive index, thereby modulating a phase of light transmitted through the semiconductor nanocrystal. .

  According to a third aspect of the present invention, in the variable optical element according to the first aspect, the refractive index is changed by causing a current to flow locally in the semiconductor nanocrystal, thereby locally modulating the phase of light transmitted through the semiconductor nanocrystal. It is characterized by doing.

  According to a fourth aspect of the present invention, in the variable optical element according to any one of the first to third aspects, the semiconductor nanocrystal is dispersed in a transparent conductive polymer, and the two transparent electrodes facing each other are dispersed. It is characterized by being sandwiched.

  According to a fifth aspect of the present invention, in the variable optical element according to the fourth aspect, a layer containing semiconductor nanocrystals dispersed in the transparent conductive polymer is provided on a transparent electrode of one transparent substrate, and the other transparent It is characterized by being superimposed on a thin film transistor substrate in which at least an X electrode, a Y electrode, a thin film transistor, and a transparent electrode to be a pixel pixel are provided in an array on the substrate.

  According to a sixth aspect of the present invention, in the variable optical element according to the fourth aspect, the layer containing semiconductor nanocrystals dispersed in the transparent conductive polymer has at least an X electrode, a Y electrode, a thin film transistor, and a pixel on a transparent substrate. One transparent electrode serving as a pixel is provided on a thin film transistor substrate provided in an array, and the other transparent electrode is formed on the layer containing the semiconductor nanocrystal.

  The invention of claim 7 provides the variable optical element according to any one of claims 4 to 6, wherein the transparent conductive polymer is polythiophene, polyparaphenylene, polyparaphenylene vinylene, polyfuran, polyfluorene, It is characterized by being at least one or a mixture of two or more selected from polyalkylfluorene, polypyrrole, polyselenophene, polyaniline, and derivatives thereof, and copolymers of these monomers.

  According to an eighth aspect of the present invention, in the variable optical element according to any one of the first to seventh aspects, the semiconductor nanocrystal is formed of one or more types of semiconductor nanocrystals. Features.

  A ninth aspect of the invention is an optical apparatus using the variable optical element according to any one of the first to eighth aspects.

  According to a tenth aspect of the present invention, in the optical device according to the ninth aspect, the optical device is a light exposure device, and the variable optical element is used for an optical diaphragm of a modified illumination of the light exposure device. And

  ADVANTAGE OF THE INVENTION According to this invention, the variable optical element which can modulate the phase of transmitted light can be obtained by using a semiconductor nanocrystal for a variable optical element and changing the refractive index of a semiconductor nanocrystal. Furthermore, there is provided a variable optical element that can locally change the optical characteristics in a desired pattern without reducing the amount of transmitted light by locally changing the refractive index of the semiconductor nanocrystal by flowing a current locally. By selecting a semiconductor nanocrystal material and its particle size, and a material used for a transparent substrate as a support base material, a variable optical element corresponding to infrared light, visible light, and ultraviolet light can be obtained.

  By using the variable optical element of the present invention, an optical device that can locally change optical characteristics into a desired pattern without reducing the amount of transmitted light becomes possible. By using the variable optical element of the present invention as an optical diaphragm for modified illumination of an optical exposure apparatus, an optical exposure apparatus having a variable aperture becomes possible, and an optical aperture shape optimum for a desired pattern shape can be easily obtained in a short time. Can do.

The variable optical element of the present invention uses a semiconductor nanocrystal, and makes the refractive index of the semiconductor nanocrystal variable. A variable optical element that changes the refractive index of the semiconductor nanocrystal by passing an electric current or the like through the semiconductor nanocrystal and modulates the phase of light transmitted through the semiconductor nanocrystal can be obtained. Furthermore, by locally controlling the current flowing through the semiconductor nanocrystal, a variable optical element whose optical characteristics can be changed into a pattern is obtained.
Hereinafter, embodiments of the variable optical element of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a schematic external view showing a variable optical element according to a first embodiment of the present invention. A variable optical element 10 whose refractive index is changed includes a transparent electrode 11 provided on a transparent substrate 11a and a transparent electrode 11 thereof. A layer (hereinafter referred to as a variable refractive index layer) 13 including a semiconductor nanocrystal 12 formed on the electrode 11, an X electrode 15 a, a Y electrode 15 b, a thin film transistor (TFT) 16, a pixel pixel, and a transparent substrate 14. And a substrate 18 (hereinafter referred to as a TFT substrate) provided with an array of transparent electrodes 17.

In the present invention, the term “transparent” means that the light transmittance is high enough to exhibit the function as an optical element in the wavelength region of light used as the optical element.
In FIG. 1, a part of the transparent electrode 11 provided with the refractive index variable layer 13 is cut away, and the refractive index variable layer 13 and the TFT substrate 18 are shown separated from each other. It is for understanding. Actually, the refractive index variable layer 13 and the TFT substrate 18 on the transparent electrode 11 are in close contact with each other.

In the present invention, the transparent substrate 11a and the transparent substrate 14 are preferably materials having high light transmittance and high surface smoothness used as optical elements, such as optically polished low expansion glass, synthetic quartz glass, and polymer films. Etc. are used.
As the transparent electrode 11 and the transparent electrode 17, a transparent conductive film in which a conductive oxide metal such as indium oxide (referred to as ITO) is formed by a method such as sputtering is used.

  As the TFT substrate 18, an active matrix driving TFT substrate used in a liquid crystal display or the like can be used. The X electrode 15 a and the Y electrode 15 b are formed of a metal thin film such as Al, Ta, and W. It is used as a source line and a gate line, and is connected to a transparent electrode 17 serving as a pixel pixel via a TFT 16.

  The semiconductor nanocrystal 12 used in the present invention is preferably used in a particle size range of 1 to 100 nm, and more preferably in a range of about 2 to 10 nm.

  By making the particle shape of the semiconductor nanocrystal 12 small and spherical, the electrons therein cannot freely move, and discrete quantization energy levels are formed. The smaller the particle size, the higher the quantization energy level of the electrons, and the light absorption edge shifts to the short wavelength side. When carriers (electrons) are injected into the quantum level of the semiconductor nanocrystal, a phenomenon (bleaching) in which the absorption coefficient of the absorption peak corresponding to the quantum level decreases is observed. At this time, the inventor has found that a change in refractive index occurs due to a change in the light absorption coefficient, and has completed the present invention that functions as a refractive index modulation element by controlling carrier injection. is there.

  According to the Kramers-Kronig relation, the refractive index changes greatly in the vicinity of the absorption peak. The relationship between the real part (ε ′) and the imaginary part (ε ″) of the dielectric constant (ε) is expressed by the following formulas 1 and 2.

  Here, ε∞ represents the real part of the dielectric constant at ω = ∞, and P represents the main value of Cauchy. The relationship between the dielectric constant and the refractive index n can be expressed as Equation 3 regarding the real part and the imaginary part, and the imaginary part of n (ω) can be described with respect to the absorption coefficient α (ω).

  For narrow absorption peaks where the absorption coefficient decreases rapidly on the long wavelength side of the absorption line, generally exponentially, the refractive index change Δn outside the full width at half maximum is a simple shape as shown in equation (4). It can be described by.

Here, α _max is the peak value of the absorption coefficient, Ω ₀ is the peak position, and Γ is the full width at half maximum of the absorption line.

As an example, when the wavelength λ ₀ is 365 nm, the peak position Ω ₀ is 330 nm, and the full width at half maximum Γ is 25 nm (0.3 eV), carriers are injected into the nanocrystal material, and the peak value of the absorption coefficient is α _max = 4 × 10 ^When changing from ⁴ cm ⁻¹ to α _max = 4 × 10 ³ cm ⁻¹ , it can be seen that a negative refractive index change (−0.0554) occurs on the long wavelength side of 35 nm (0.36 eV) from the peak position. .

Assuming that the refractive index difference acting as the variable optical element is four-valued, it is necessary to add a maximum phase difference of 3 / 4λ (3 / 2π) of the light transmitted through the element. The relationship between the refractive index difference (Δn = n ₀ −n ₁ ) and the phase difference (ΔΦ) is given by Equation 5. Here, L is the element length.

  When the wavelength of light is 365 nm and the element length is 5 μm, the refractive index difference Δn that gives a phase difference (ΔΦ) of 3 / 2π is 0.0548. It can be seen that a refractive index difference for obtaining a quaternary phase difference can be obtained. In the case of binary values, a phase difference of λ / 2 (π) can be obtained with a refractive index of 0.0365, so that the refractive index difference may be small.

  Examples of the material of the semiconductor nanocrystal 12 used in the present invention include I-VII compounds such as CuCl, II-VI compounds such as CdS, CdSe, CdTe, CdO, ZnS, ZnSe, ZnTe, ZnO, GaAs, and GaP. There are III-V group compounds such as InS, GaAlAs, InAlAs, etc., and one or more of these materials can be mixed and used as the semiconductor nanocrystal 12. For example, a semiconductor nanocrystal such as CdSe, CdSe / ZnS, or CdTe / CdS can be used when the light used as the optical element is in the visible region, and ZnO can be used when the light is in the ultraviolet region. As the nanocrystal cap material, TOPO (Tricylphosphine), alkylamine, or the like is used.

  The semiconductor nanocrystal 12 is preferably dispersed in a transparent conductive binder resin and used as a resin solution. The binder resin solution is applied onto the transparent electrode 11 by a method such as a spin coating method, an ink jet method, or a screen printing method, The refractive index variable layer 13 is formed by drying and removing water or other solvent used in the solution.

In the present invention, as the conductive binder resin for dispersing the semiconductor nanocrystals, a transparent conductive polymer 12a having a high transmittance in the wavelength region of light used as an optical element is used.
As the transparent conductive polymer 12a, polythiophene, polyparaphenylene, polyparaphenylene vinylene, polyfuran, polyfluorene, polyalkylfluorene, polypyrrole, polyselenophene, polyaniline, and derivatives thereof, and copolymerization of these monomers A mixture of at least one or two or more selected from those can be used. Among the above transparent conductive polymers, a conductive polymer containing polydioxythiophene is more preferable because it is easily dissolved or dispersed in water or other solvents, has high transparency and conductivity, and is excellent in film formability.

In the present invention, the concentration of the semiconductor nanocrystal 12 contained in the transparent conductive polymer 12a is preferably in the range of about 0.1 to 50 parts of the semiconductor nanocrystals with respect to 100 parts of the resin.
In the formed refractive index variable layer 13, the periphery of the semiconductor nanocrystal 12 is surrounded by the conductive polymer 12a.

  Next, the effect of the semiconductor nanocrystal 12 of the present invention will be described. The semiconductor nanocrystal 12 has a spherical shape with a particle size of about 1 to 10 μm, so that electrons can only exist at the quantization energy level due to the so-called quantum size effect, and the quantization energy level becomes smaller as the particle size becomes smaller. Get higher. That is, as the particle size becomes smaller, the light absorption wavelength of the semiconductor nanocrystal 12 shifts to the shorter wavelength side. Then, an external carrier such as an electric current is applied to the semiconductor nanocrystal 12 to change the absorption coefficient of light absorption of the semiconductor nanocrystal 12, thereby causing a change in the refractive index of the semiconductor nanocrystal 12. This causes a phase change of the transmitted light. In this case, the transmitted light is preferably transparent region light having a longer wavelength than the absorption edge of light absorption of the semiconductor nanocrystal 12. In this case, since the change of the occupation state of the carrier due to light absorption can be ignored, the refractive index modulation is not affected.

  In the present invention, the current applied from the outside is due to the two transparent electrodes facing each other. More preferably, in order to control the current locally, at least one of the transparent electrodes is a thin film transistor (TFT). ) Is preferred. The semiconductor nanocrystal 12 provided on the transparent electrode of the transparent substrate and the arrayed TFT substrate are overlapped, and the current flowing between the two transparent electrodes facing each other is controlled by controlling the current of the predetermined TFT. The refractive index of 12 can be locally modulated, and the phase of light transmitted through a desired portion of each pixel in the array can be changed.

  The transmitted light 19 enters the variable optical element 10 from the TFT substrate 18 side and exits from the refractive index variable layer 13 side. At this time, a current is passed through a desired pixel to cause a change in the refractive index of a predetermined semiconductor nanocrystal 12, and to cause a phase change of light that is locally transmitted through the semiconductor nanocrystal 12 in a pattern. In this way, it is possible to obtain a variable optical element that can locally change the optical characteristics into a desired pattern without reducing the amount of light transmitted through the optical element. Moreover, a variable optical element corresponding to infrared light, visible light, and ultraviolet light can be obtained by selecting a semiconductor nanocrystal material, its particle size, and a material used for a transparent substrate as a support substrate.

(Second Embodiment)
FIG. 2 is a schematic external view showing a second embodiment of the variable optical element of the present invention. The variable optical element 20 whose refractive index can be changed is formed on a transparent substrate 24 with an X electrode, a Y electrode, a thin film transistor (TFT). ) And a transparent electrode to be a pixel pixel on a TFT substrate 28 provided in an array, a layer (hereinafter referred to as a refractive index variable layer) 23 in which a semiconductor nanocrystal 22 is formed, and a transparent electrode 21 are provided. Formed. In FIG. 2, the TFT surface is not shown because it is covered with the refractive index variable layer 23, but the same TFT substrate as the TFT substrate 1 of FIG. 1 can be used.

In the first embodiment, the refractive index variable layer having the semiconductor nanocrystal is formed on the transparent substrate, whereas in the second embodiment, the refractive index variable layer 23 having the semiconductor nanocrystal 22 is formed on the TFT substrate 28. It is formed directly on the top. The semiconductor nanocrystal 22 is preferably used in a form dispersed in the transparent conductive polymer 22a. The other transparent electrode 21 opposite to the transparent electrode of the TFT substrate is formed on the entire surface of the refractive index variable layer 23.
The transparent electrode 21 may be formed and formed directly on the refractive index variable layer 23 by a method such as sputtering, or the transparent electrode formed on the transparent substrate may be adhered and overlapped.

  In the second embodiment, the same materials and methods as those in the first embodiment can be used for the TFT substrate 28, the semiconductor nanocrystal 22, and the transparent conductive polymer 22a as the binder resin and the coating method.

  Although not shown in FIG. 2, in the present embodiment, a mode in which a transparent protective layer is further provided on the transparent electrode 21 with a glass substrate or a transparent resin is also possible. In this case, the refractive index of the protective layer is preferably approximately the same as that of the transparent substrate 24.

  As schematically shown in FIG. 2, the light 29 incident on the variable optical element 20 has a predetermined phase on the incident side to the TFT substrate, but the semiconductor nanocrystal 22 of the refractive index variable layer 23 By transmitting the light, the phase is modulated, and the outgoing light becomes the outgoing light 29b having a different phase. In this way, it is possible to obtain a variable optical element that can locally change the optical characteristics into a desired pattern without reducing the amount of light transmitted through the optical element.

(Optical device)
The variable optical element of the present invention can change the refractive index of an arbitrary shape in the transparent region, and by selecting a semiconductor nanocrystal material constituting the variable optical element, its particle size, and a support substrate It can be applied to optical devices for various uses corresponding to infrared light, visible light, and ultraviolet light. For example, it can be used for an imaging device, a display device, an optical measurement device, a light exposure device, and the like.
Next, the case where the variable optical element of the present invention is used for an optical diaphragm of an optical exposure apparatus will be described.

(Light exposure equipment)
FIG. 3 is a schematic view of a light exposure apparatus when the variable optical element of the present invention is used for an optical diaphragm for modified illumination of a light exposure apparatus (stepper). The light exposure apparatus shown in FIG. 3 includes a modified illumination system 34 including a light source 31 such as a mercury lamp or an excimer laser, an optical aperture 32 using the variable optical element of the present invention, and a condenser lens 33, and a photo having a predetermined pattern. It comprises a mask (also referred to as a reticle) 35, a projection lens 36, and a substrate 37 provided with a resist film on the projection surface. In this case, because of the modified illumination, the position where the exposure light 38 for exposing the resist film passes through the optical aperture 32 is shifted from the optical axis of the apparatus, and the incident light to the photomask 35 is inclined.

  In the optical exposure apparatus of the present invention, the shape of the light source is defined by the shape of the phase difference modulation area where the phase difference of the light of the optical aperture 32 is different from the surroundings, and the phase difference modulation area of the optical aperture 32 is variable. is there. When changing the shape of the light source according to the purpose of use, a current is locally passed through the array of TFT substrates at a predetermined position of the optical diaphragm 32 by the variable optical element, and the phase difference modulation regions having different desired phase differences are patterned. What is necessary is just to form.

  FIG. 4 is a schematic plan view showing an example of the shape of the optical diaphragm using the variable optical element according to the present invention. FIG. 4 (a) is a region in which two linear phase differences are provided, and FIG. 4 (b) is a substantially circular shape in which a region having different phase differences is provided. FIG. 4C shows four substantially circular regions with different phase differences. Each of the shapes in FIGS. 4A to 4C is formed by one optical aperture. Note that the above-described substantially circular shape does not necessarily have to be a perfect circle due to the structure of the TFT substrate, but the roundness can be increased as the pixel pixels of the TFT array are miniaturized.

In this way, an optical exposure apparatus using the optical diaphragm 32 with a variable optical element capable of locally changing the optical characteristics into a desired pattern is obtained.
According to the light exposure apparatus of the present invention, there is no need to replace an optical aperture having a different hole shape for transmitted light according to the purpose of use as in the prior art. It can be shortened. Furthermore, it becomes possible to set an optical aperture that is optimal for the pattern shape of the photomask to be exposed, and the resolution of the resist pattern can be maximized.
Hereinafter, the present invention will be described in more detail by way of examples.

Example 1
An ITO film was formed by sputtering on an optically polished quartz glass substrate having a thickness of 1 mm to form a transparent electrode having a surface resistance of 80 Ω / cm ² .
Next, ZnO having a particle diameter of 1 to 10 nm as a semiconductor nanocrystal material is dispersed in a conductive polymer aqueous solution (solid content: 5%) made of polyethylenedioxythiophene and polysulfonic acid as a binder resin, and the semiconductor nanocrystal of ZnO is dispersed. A conductive polymer solution was prepared. The concentration of semiconductor nanocrystals contained in the binder resin was 3 parts of semiconductor nanocrystals per 100 parts of resin.

  Next, the conductive polymer solution of the semiconductor nanocrystal is spin-coated on the transparent electrode of the quartz glass substrate, and after the film is formed, moisture is removed by drying. The thickness of the semiconductor nanocrystal and the conductive polymer is formed on the transparent electrode. A substrate provided with a 5 μm thick refractive index variable layer was obtained.

On the other hand, on a quartz glass substrate with a thickness of 1 mm, which is different from the above, pixel pixels are formed in an array using W metal thin film with X electrode, Y electrode, amorphous silicon with TFT, and surface resistance of 80Ω / cm ² ITO. A TFT substrate was obtained.
Next, the substrate provided with the above-described variable refractive index layer was superposed on this TFT substrate to form an array-shaped variable optical element in which the variable refractive index layer substrate and the TFT substrate were integrated.

This variable optical element is applied to an optical aperture of an i-line stepper, a current is passed through a predetermined TFT, and the refractive index of a portion of the semiconductor nanocrystal corresponding to the pixel pixel of that portion is changed to form a stop in a pattern. When the i-line resist on the semiconductor was exposed to light by a modified illumination method to form a pattern, a fine resist pattern with high resolution was formed.
Furthermore, by changing the pattern of the optical aperture to another shape, it was possible to easily obtain the optical aperture shape optimal for the desired pattern shape in a short time.

(Example 2)
The conductive polymer solution of the semiconductor nanocrystal made of ZnO used in Example 1 is directly applied to the TFT substrate in which pixel pixels are formed in an array on the quartz glass substrate having a thickness of 1 mm with an X electrode, a Y electrode, TFT, and ITO. After spin coating, moisture was removed by drying, and a 5 μm-thick refractive index variable layer made of semiconductor nanocrystals and a conductive polymer was provided on the TFT substrate. Subsequently, ITO was formed on the entire surface of the semiconductor nanocrystal by sputtering to form a transparent electrode having a surface resistance value of 80 Ω / cm ² , thereby obtaining a variable optical element having a refractive index variable layer.

  As in Example 1, this variable optical element is applied to an optical aperture of an i-line stepper, and a current is passed through a predetermined TFT, and the refractive index of the semiconductor nanocrystal in that portion is changed to form the aperture in a pattern. When the i-line resist on the semiconductor was exposed by the modified illumination method, a fine resist pattern with high resolution was formed.

It is an external appearance schematic diagram which shows 1st Embodiment of the variable optical element of this invention. It is an external appearance schematic diagram which shows 2nd Embodiment of the variable optical element of this invention. It is the schematic of the optical exposure apparatus using the optical aperture diaphragm by the variable optical element of this invention. It is a top view of the shape example of the optical aperture stop by the variable optical element of this invention. This is a conventional variable optical element using a polymer dispersed liquid crystal or a polymer stabilized liquid crystal.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10, 20 Variable optical element 11, 21 Transparent electrode 11a Transparent substrate 12, 22 Semiconductor nanocrystal 12a, 22a Transparent conductive polymer 13, 23 Refractive index variable layer 14, 24 Transparent substrate 15a X electrode 15b Y electrode 16 Thin film transistor (TFT)
DESCRIPTION OF SYMBOLS 17 Transparent electrode 18 TFT substrate 19, 29 Light 29a Incident light 29b Outgoing light 31 Light source 32 Optical diaphragm 33 Condenser lens 34 Deformation illumination system 35 Photomask 36 Projection lens 37 Substrate provided with a resist film (projection surface)
38 Exposure light 41, 43, 45 Optical aperture 42, 44, 46 Phase modulation region of light 50 Liquid crystal variable hologram element 51, 52 Transparent electrode 53 Liquid crystal molecule 54 Drive power supply 55 Nematic liquid crystal particles 56, 57 Transparent substrate 58 Polymer layer 59 Liquid crystal layer

Claims (10)

  A variable optical element using a semiconductor nanocrystal, wherein the refractive index of the semiconductor nanocrystal is changed.   2. The variable optical element according to claim 1, wherein a current is passed through the semiconductor nanocrystal to change a refractive index to modulate a phase of light transmitted through the semiconductor nanocrystal.   2. The variable optical element according to claim 1, wherein a current is locally passed through the semiconductor nanocrystal to change a refractive index and locally modulate a phase of light transmitted through the semiconductor nanocrystal.   4. The variable optics according to claim 1, wherein the semiconductor nanocrystal is dispersed in a transparent conductive polymer and sandwiched between two transparent electrodes facing each other. 5. element.   A layer containing semiconductor nanocrystals dispersed in the transparent conductive polymer is provided on a transparent electrode of one transparent substrate, and at least an X electrode, a Y electrode, a thin film transistor, and a transparent pixel pixel are formed on the other transparent substrate. 5. The variable optical element according to claim 4, wherein the electrodes are superposed on a thin film transistor substrate provided in an array.   A layer containing semiconductor nanocrystals dispersed in the transparent conductive polymer is provided on a thin film transistor substrate in which at least an X electrode, a Y electrode, a thin film transistor, and one transparent electrode to be a pixel pixel are provided in an array on a transparent substrate. The variable optical element according to claim 4, wherein the other transparent electrode is formed on the layer including the semiconductor nanocrystal.   The transparent conductive polymer is polythiophene, polyparaphenylene, polyparaphenylene vinylene, polyfuran, polyfluorene, polyalkylfluorene, polypyrrole, polyselenophene, polyaniline, and derivatives thereof, and copolymers of these monomers The variable optical element according to claim 4, wherein the variable optical element is at least one selected from the group consisting of two or more.   The variable optical element according to claim 1, wherein the semiconductor nanocrystal is formed of one or more semiconductor nanocrystals.   An optical device using the variable optical element according to claim 1. The optical apparatus according to claim 9, wherein the optical apparatus is an optical exposure apparatus, and the variable optical element is used for an optical diaphragm of a modified illumination of the optical exposure apparatus.

Images