CN115023649A

CN115023649A - Light control device, image display device, and display device

Info

Publication number: CN115023649A
Application number: CN202080095014.XA
Authority: CN
Inventors: 河野正洋; 町田晓夫; 角野宏治; 仲山正二
Original assignee: Sony Group Corp
Current assignee: Sony Group Corp
Priority date: 2020-02-05
Filing date: 2020-12-24
Publication date: 2022-09-06
Also published as: JPWO2021157247A1; WO2021157247A1

Abstract

The light control device 700 of the present disclosure includes a1 st electrode 712A, a 2 nd electrode 712B facing the 1 st electrode 712A, a light control layer 716 sandwiched between the 1 st electrode 712A and the 2 nd electrode 712B, and a control unit 30 controlling coloring/decoloring of the light control layer 716, the control unit 30 includes a secondary battery 31, a control circuit 32, and a capacitor 33, and the control unit 33 controls (a) charging of the capacitor 33 by the secondary battery 31 and (B) voltage application to the 1 st electrode 712A and the 2 nd electrode 712B based on discharging of the capacitor 33 at the time of coloring or decoloring of the light control layer 716.

Description

Light control device, image display device, and display device

Technical Field

The present disclosure relates to a light control device, an image Display device provided with the light control device, and a Display device provided with the image Display device, and more particularly, for example, to a Display device used for a Head Mounted Display (HMD).

Background

In recent years, an Augmented Reality technology (AR technology) for synthesizing and presenting various information as electronic information as additional information in a real environment (or a part thereof) has been attracting attention. In order to realize the augmented reality technology, for example, a head mounted display is studied as a device for presenting visual information. In addition, as an application field, work support in a real environment is expected, and examples thereof include provision of road guidance information, provision of technical information for a technician who performs maintenance or the like, and the like. In particular, the head-mounted display is very convenient because it does not take up hands. In addition, when viewing videos and images while moving outdoors, the videos, images and the external environment can be captured simultaneously in the field of view, and thus the videos and images can be smoothly moved.

A virtual image display device (display device) for allowing an observer to observe a two-dimensional image formed by an image forming device as an enlarged virtual image through a virtual image optical system is known. Further, by forming a virtual image based on a two-dimensional image in the display device, the observer can view an image of the outside world and the formed virtual image in an overlapping manner. However, in the case where the surrounding environment where the display device is placed is very bright or depending on the content of the virtual image formed, there may be a problem that sufficient contrast cannot be provided to the virtual image observed by the observer. Therefore, for example, a virtual image display device (display device) including a light control device is known from international publication No. WO2019/097895, which solves such a problem.

Documents of the prior art

Patent literature

Patent document 1: WO2019/097895 publication

Disclosure of Invention

Problems to be solved by the invention

However, when a light control layer constituting a light control device is formed of an electrochromic material or the like and the transmittance of light is changed by applying a color change based on an electrochemical redox reaction of a substance constituting the light control layer, which is generated by flowing an electric current through the light control layer, it may be difficult to color (develop color) or erase the light control layer in a short time (for example, within 12 seconds if it is a goggle shape or within 4 seconds if it is a spectacle size).

Accordingly, an object of the present disclosure is to provide a light control device having a configuration capable of coloring or decoloring in a short time, an image display device including the light control device, and a display device including the image display device.

Means for solving the problems

The light control device of the present disclosure for achieving the above object includes:

a1 st electrode;

a 2 nd electrode facing the 1 st electrode;

a light control layer sandwiched between the 1 st electrode and the 2 nd electrode; and

a control part for controlling the coloring/decoloring of the light adjusting layer,

the control unit includes a secondary battery, a control circuit, and a capacitor,

the control part controls:

(A) charging of a capacitor using a secondary battery; and

(B) the voltage is applied to the 1 st electrode and the 2 nd electrode based on the discharge of the capacitor at the time of coloring or decoloring of the light adjusting layer.

The image display device of the present disclosure for achieving the above object includes:

an image forming apparatus;

an optical device having a virtual image forming region in which a virtual image is formed from light emitted from the image forming device; and

a light control device that is disposed so as to face at least the virtual image forming region and adjusts the amount of external light that enters from the outside,

the dimming device is composed of the dimming device of the present disclosure.

The display device of the present disclosure for achieving the above object includes:

a frame to be worn on a head of an observer; and

an image display device mounted on the frame, wherein,

the image display device includes:

an image forming apparatus;

the dimming device is constituted by the dimming device of the present disclosure.

Drawings

Fig. 1A and 1B are a schematic front view of an optical device and a light control device (of which, the right eye is concerned) in a display device of example 1, and a schematic cross-sectional view along an arrow B-B in fig. 1A, respectively.

Fig. 2A and 2B are a schematic front view of an optical device and a light control device (of which, the right eye is the one) in a modification of the display device of embodiment 1, and a schematic cross-sectional view along arrow B-B in fig. 2A, respectively, and fig. 2C is a schematic front view of a modification of the light control device.

Fig. 3A and 3B are a schematic cross-sectional view of the same light control device as shown by the arrow B-B in fig. 1A and a schematic side view of the display device (mainly for the right eye) when the display device is viewed from the left eye side, respectively.

Fig. 4 is a conceptual diagram of an image display device in the display device of embodiment 1.

Fig. 5 is a conceptual diagram of a modification of the image display device in the display device of embodiment 1.

Fig. 6 is a schematic view of the display device of embodiment 1 as viewed from above.

Fig. 7 is a schematic view of the display device of embodiment 1 as viewed from the front.

Fig. 8 is a graph showing an example of a relationship between the voltage (Δ V) applied between the 1 st electrode and the 2 nd electrode constituting the light control device and the light transmittance.

The upper, middle, and lower stages of fig. 9 are graphs showing temporal changes in the voltage applied between the 1 st electrode and the 2 nd electrode constituting the light control device, the current flowing through the light control layer, and the light transmittance, respectively, in a state after the start of coloring.

The upper, middle, and lower stages of fig. 10 are graphs showing temporal changes in the voltage applied between the 1 st electrode and the 2 nd electrode constituting the light control device, the current flowing through the light control layer, and the light transmittance in the state after the start of decoloring.

Fig. 11A and 11B are conceptual views of a control unit constituting a light control device in embodiment 1 and a modification-1 thereof.

Fig. 12 is a conceptual diagram of a modification-2 of the control unit constituting the light control device in embodiment 1.

Fig. 13 is a block diagram showing an example of the circuit configuration of the control circuit and the secondary battery.

Fig. 14A and 14B are an equivalent circuit diagram of a charging circuit for charging a capacitor and a diagram showing changes in potential at each part of the equivalent circuit diagram shown in fig. 14A, respectively.

Fig. 15A and 15B are equivalent circuit diagrams of a light transmittance/polarity control circuit for controlling the light transmittance and changing the polarity of the voltage applied to the 1 st electrode and the 2 nd electrode.

Fig. 16 is a circuit diagram of another driving circuit of the dimming device 700.

Fig. 17 is a diagram showing an operation explanation of the drive circuit shown in fig. 16.

Fig. 18 is a conceptual diagram of an image display device in the display device of embodiment 2.

Fig. 19 is a conceptual diagram of an image display device in the display device of embodiment 3.

Fig. 20 is a schematic cross-sectional view showing a part of a reflection type volume hologram diffraction grating in the display device of example 3 in an enlarged manner.

Fig. 21 is a conceptual diagram of an image display device in the display device of embodiment 4.

Fig. 22 is a schematic view of the display device of example 5 viewed from above.

Fig. 23A and 23B are a schematic diagram of the display device of example 6 and a schematic diagram of a circuit for controlling the illuminance sensor, respectively, as viewed from above.

Fig. 24A and 24B are a schematic diagram of the display device of example 7 and a schematic diagram of a circuit for controlling the illuminance sensor, respectively, as viewed from above.

Fig. 25A and 25B are schematic cross-sectional views of the light control devices of embodiment 8 and embodiment 9, respectively, similar to the arrows B-B along fig. 1A.

Fig. 26 is a schematic view of a further modification of the display device of embodiment 1 as viewed from above.

Fig. 27A, 27B, 27C, 27D, 27E, 27F, 27G, and 27H are conceptual views of an optical device in a further modification of the display device of embodiment 1.

Fig. 28 is a conceptual diagram of an optical device in still another modification of the display device of embodiment 1.

Fig. 29A and 29B are schematic diagrams of an optical device in a modification of the display device of example 5, as viewed from above.

Fig. 30A and 30B are schematic views of an optical device in another modification of the display device of example 5, viewed from above and from the side, respectively.

Fig. 31 is a flowchart showing a flow of the operation of the light control device of embodiment 1.

Detailed Description

The present disclosure will be described below with reference to the drawings and examples, but the present disclosure is not limited to the examples, and various numerical values and materials in the examples are examples. The following procedure is described.

1. Description of the light control device of the present disclosure, the image display device of the present disclosure, and the entire display device of the present disclosure

2. Example 1 (light control device of the present disclosure, image display device of the present disclosure, optical device of the 1 st-a structure, image forming device of the 1 st structure)

3. Example 2 (modification of example 1, optical device of the 1 st to A Structure, image Forming apparatus of the 2 nd Structure)

4. Example 3 (another modification of example 1, optical device of the 1 st to B constructions, image forming apparatus of the 1 st construction)

5. Example 4 (still another modification of example 1, the optical device of the 1 st to B structure, the image forming apparatus of the 2 nd structure)

6. Example 5 (still another modification of example 1, the optical device of the 2 nd configuration, the image forming apparatus of the 2 nd configuration)

7. Example 6 (modifications of examples 1 to 5)

8. Example 7 (another modification of examples 1 to 5)

9. Example 8 (modifications of examples 1 to 7)

10. Example 9 (another modification of examples 1 to 7)

11. Others

< description of the light control device of the present disclosure, the image display device of the present disclosure, and the display device of the present disclosure as a whole >

In the light control device of the present disclosure, the light control device constituting the image display device of the present disclosure, and the light control device constituting the display device of the present disclosure (hereinafter, these may be collectively referred to as "the light control device of the present disclosure, etc."), the following modes can be adopted: the control part also controls

(C) And applying a voltage to the 1 st electrode and the 2 nd electrode by the secondary battery after a predetermined time has elapsed from the start of coloring or decoloring of the light control layer.

Furthermore, a predetermined time T is elapsed from the coloring of the dimming layer ₀ ' thereafter, voltage application to the 1 st electrode and the 2 nd electrode by the secondary battery is performed, but a predetermined time (coloring/predetermined time) may be elapsed)T ₁ After that, the voltage application to the 1 st electrode and the 2 nd electrode by the secondary battery is stopped. Similarly, a predetermined time T elapses from the decoloring of the light control layer ₀ "thereafter, voltage application to the 1 st electrode and the 2 nd electrode is performed by the secondary battery, but the predetermined time (decoloring/predetermined time) T may be elapsed ₁ "thereafter, the application of voltage to the 1 st electrode and the 2 nd electrode by the secondary battery is stopped. In some cases, the predetermined time T may be elapsed from the start of decoloring the light control layer ₀ "thereafter, the application of voltage to the 1 st electrode and the 2 nd electrode by the secondary battery is stopped. In addition, when coloring the light control layer, the value of the voltage applied to the 1 st electrode and the 2 nd electrode based on the discharge of the capacitor and the predetermined time T elapsed from the coloring of the light control layer ₀ After that, the values of the voltages applied to the 1 st electrode and the 2 nd electrode by the secondary battery may be set to the same value, and the value of the light transmittance of the light control layer may be defined by the voltages. The predetermined time T can also be set ₀ 、T ₀ ’、T ₀ ", predetermined time (coloring/predetermined time) T ₁ ', predetermined time (erasing/predetermined time) T ₁ "stored in advance in the control unit. Alternatively, the control unit may measure the voltages applied to the 1 st electrode and the 2 nd electrode, and when the voltages applied to the 1 st electrode and the 2 nd electrode reach a predetermined voltage or a predetermined voltage, the control unit may determine that the predetermined time T has been reached ₀ 、T ₀ ’、T ₀ ", prescribed time (coloring/prescribed time) T ₁ ', predetermined time (erasing/predetermined time) T ₁ ”。

In the light control device and the like of the present disclosure including the above preferred embodiments, the following embodiments can be provided:

the control unit applies a positive potential to one of the 1 st electrode and the 2 nd electrode and a negative potential to the other of the 1 st electrode and the 2 nd electrode during coloring of the light control device,

the control unit applies a voltage having a polarity opposite to that of the voltage applied to the 1 st electrode and the 2 nd electrode during coloring of the light control device during color erasing of the light control device. Specifically, for example, a voltage relatively higher than that of the 1 st electrode is applied to the 2 nd electrode during coloring of the light control device, and for example, a voltage relatively higher than that of the 2 nd electrode is applied to the 1 st electrode during decoloring of the light control device.

In the light control device of the present disclosure including the various preferred embodiments described above, the following embodiments can be provided:

q is the amount of charge for providing a desired light transmittance to the light-adjusting layer at the time of coloring ₀ The charge amount of the charged capacitor is Q ₁ A predetermined time T will elapse from the start of coloring or decoloring of the light control layer ₀ The charge amount of the capacitor is set to Q ₂ To satisfy

0.4<(Q ₁ -Q ₂ )/Q ₀

Preference is given to

1.0≤(Q ₁ -Q ₂ )/Q ₀ ≤10.0

In the embodiment, the control unit controls the voltage applied to the capacitor and the 1 st and 2 nd electrodes. Further, the following modes can be cited: as T ₀ A value of (b) satisfies

T is more than or equal to 0.1 (second) ₀ Less than or equal to 12 (second)

Preference is given to

T is more than or equal to 0.8 (second) ₀ Less than or equal to 4 seconds.

In addition, the predetermined time T may be set from the start of coloring of the light control device ₀ ' and a predetermined time T from the start of decoloring of the dimming device ₀ "may be the same or different. Specifically, for example, examples can be given

T ₀ ＝T ₀ ’＝T ₀ ”

Or alternatively

T ₀ ＝T ₀ ’>T ₀ ”

The relationship (2) of (c). Further, more specifically, with respect to T ₀ 、T ₀ ’、T ₀ The value of "may be determined by performing various tests in the light control device.

In the light control device of the present disclosure including the various preferred embodiments described above, a mode can be adopted in which a current flows through the light control layer when a voltage is applied to the 1 st electrode and the 2 nd electrode.

Specifically, the following method can be adopted: the dimming layer is constituted by a light shutter (shutter) to which a color change of a substance generated by a redox reaction of an inorganic or organic electrochromic material is applied. More specifically, the light control layer may include an inorganic or organic electrochromic material. That is, the light control layer may have a laminated structure of a reduction coloring layer made of tungsten oxide, an electrolyte layer made of tantalum oxide, and an oxidation coloring layer containing iridium atoms, for example, and in this case, the oxidation coloring layer may be made of an iridium tin oxide material. Specifically, the light modulation layer may have WO from the 1 st electrode side ₃ layer/Ta ₂ O ₅ layer/Ir _X Sn _1-X Laminated structure of inorganic electrochromic material layers such as O layer, or WO ₃ layer/Ta ₂ O ₅ layer/IrO _x A laminated structure of inorganic electrochromic material layers such as layers. Substitute WO ₃ Layer, can use MoO ₃ Layer, V ₂ O ₅ And (3) a layer. In addition, instead of IrO _x Layer of not only ZrO ₂ The layer or zirconium phosphate layer may be formed using a prussian blue complex/nickel-substituted prussian blue complex, and examples thereof include organic materials such as viologen derivatives, polythiophene derivatives, and prussian blue derivatives, and rhodium oxide (RhO) may be used as a material constituting the oxidation colored layer _x ) Nickel oxide (NiO) _x ) Chromium oxide (CrO) _x ) Zirconium oxide (ZrO) _x ) Inorganic materials such as zirconium phosphate, nickel hydroxide and copper chloride, metal complexes (prussian blue complex and ruthenium violet complex), and iron pentacyanococarbonyl ferrite; amine derivatives, phenazine, viologen derivatives, and the like. Examples of the electrolyte layer include gels and ionomers such as propylene carbonate, ionic liquids, acetonitrile, ethylene carbonate, and propylene carbonate.

Alternatively, the light control device may include an optical shutter based on a plating method (electrodeposition method or field deposition method) to which a plating/dissociation phenomenon caused by a reversible redox reaction of a metal (e.g., silver particles) is applied, that is, a method in which the light control layer includes an electrolyte containing metal ions. Such a dimming device is described in detail in example 9.

The color to be colored by the light control device may be a fixed color such as blue, brown, or black, or may be a color to be colored by the light control device to a desired color, or the color to be colored by the light control device may be variable. Specifically, for example, a light control device colored red, a light control device colored green, and a light control device colored blue may be stacked. In the present specification, the term "coloring" includes "coloring".

In the light control device of the present disclosure including the various preferred embodiments described above, a moisture holding member (described in detail later) may be disposed at least between the 2 nd electrode and the 2 nd substrate.

In the light control device of the present disclosure including the various preferred embodiments described above, the following embodiments can be provided: the effective area of the light modulation layer is A (mm) ² ) When the capacitance of the capacitor is C (farad), the capacitance satisfies

C/A>1×10 ^-6 (F/mm ² )。

In the light control device of the present disclosure and the like including the various preferred embodiments described above, the capacitor may be configured by a plurality of capacitors connected in parallel.

In the light control device of the present disclosure including the various preferred embodiments described above, the following embodiments can be provided: the control circuit includes:

a current limiting circuit that limits a current at the time of discharge of the secondary battery; and

and a voltage control circuit (regulator) for controlling voltages applied to the 1 st electrode and the 2 nd electrode from the capacitor and the secondary battery.

In the light control device of the present disclosure including the various preferred embodiments described above, the secondary battery may be configured as a lithium ion battery.

The light control device of the present disclosure including the various preferred embodiments described above can be configured as follows:

comprises a1 st substrate and a 2 nd substrate facing the 1 st substrate,

the 1 st electrode is provided on the facing surface of the 1 st substrate facing the 2 nd substrate,

the 2 nd electrode is provided on the facing surface of the 2 nd substrate facing the 1 st substrate.

Specific examples of the material forming the transparent 1 st substrate and the transparent 2 nd substrate constituting the light control device include transparent glass substrates such as soda lime glass and white board glass, plastic substrates, plastic sheets, and plastic films. Examples of the plastic include cellulose esters such as polyethylene terephthalate, polyethylene naphthalate, polycarbonate, and cellulose acetate, fluorine polymers such as polyvinylidene fluoride or copolymers of polytetrafluoroethylene and hexafluoropropylene, polyethers such as polyoxymethylene, polyacetals, polystyrenes, polyethylenes, polypropylenes, and polyolefins such as methylpentene polymers, polyimides such as polyamideimide or polyetherimide, polyamides, polyether sulfones, polyphenylene sulfides, polyvinylidene fluoride, tetraacetyl cellulose, brominated phenoloxides, polyarylates, polysulfones, COP (cycloolefin polymer), TAC films, and highly transparent self-adhesive acrylic films. The plastic sheet or film may have rigidity that does not easily bend, or may have flexibility. When the 1 st substrate and the 2 nd substrate are formed of transparent plastic substrates, a barrier layer made of an inorganic material or an organic material may be formed on the inner surface of the substrates.

The 2 nd substrate also has a function as a protective substrate, for example. The 1 st substrate faces the optical device with a gap, faces the optical device without a gap, or also serves as a member constituting the optical device (for example, a protective member provided in the optical device). A hard coat layer (for example, made of acrylic modified colloidal silica particles, organic materials of a phenyl group and an acrylate group, and methyl ethyl ketone) made of an organic/inorganic mixed layer and an antireflection film made of a fluorine resin may be formed on the outer surface of the 2 nd substrate.

Further, if necessary, the inorganic material film may be provided on the 2 nd substrate, so that rigidity can be imparted to the 2 nd substrate, and distortion is less likely to occur in the 2 nd substrate when the light control device is mounted. Examples of the inorganic material film include alumina, silicon oxide, silicon nitride, and niobium oxide. The inorganic material film can be formed by, for example, a PVD method, a CVD method, a laser ablation method, or an atomic layer deposition method (ALD method).

The 1 st substrate and the 2 nd substrate are sealed and bonded at their outer peripheral portions with a sealing agent. As the sealing agent, various resins such as epoxy resin, urethane resin, acrylic resin, vinyl acetate resin, olefin thiol resin, silicone resin, modified polymer resin, and the like, heat curing type, photo curing type, moisture curing type, anaerobic curing type, and the like can be used.

In the light control device of the present disclosure and the like including the various preferred embodiments described above, the following embodiments can be provided:

the 1 st electrode is composed of a plurality of 1 st electrode segments (segments) in a strip shape extending in the 1 st direction,

the 2 nd electrode is composed of a plurality of strip-shaped 2 nd electrode segments extending in a 2 nd direction different from the 1 st direction,

the control of the light blocking rate of the portion of the light control device corresponding to the repetition region (minimum unit region where the light blocking rate of the light control device changes) of the 1 st electrode segment and the 2 nd electrode segment is performed according to the control of the voltage applied to the 1 st electrode segment and the 2 nd electrode segment. That is, the light shielding rate can be controlled according to the simple matrix system. An example in which the 1 st direction and the 2 nd direction are orthogonal can be given. When the light control device is colored, for example, a voltage higher than that of the 1 st electrode is applied to the 2 nd electrode, and when the light control device is decolored, for example, a voltage higher than that of the 2 nd electrode is applied to the 1 st electrode.

Alternatively, a Thin Film Transistor (TFT) may be provided in each of the minimum unit regions for controlling the light shielding rate of the minimum unit region in which the light shielding rate of the light control device changes. That is, the light shielding rate may be controlled according to an active matrix (active matrix) system. Alternatively, either one of the 1 st electrode and the 2 nd electrode may be a so-called beta electrode (electrode not patterned), or both may be so-called beta electrodes (electrode not patterned).

As described above, the 1 st electrode may or may not be patterned. The 2 nd electrode may or may not be patterned. Examples of the material constituting the 1 st electrode and the 2 nd electrode include a transparent conductive material, specifically, Indium Tin Oxide (ITO) containing Sn-doped In ₂ O ₃ Crystalline ITO and amorphous ITO), fluorine-doped SnO ₂ (FTO), IFO (F-doped In) ₂ O ₃ ) Antimony doped SnO ₂ (ATO)、SnO ₂ ZnO (including Al-doped ZnO and B-doped ZnO), Indium-Zinc composite Oxide (IZO), spinel-type Oxide, and YbFe ₂ O ₄ And structured oxides, conductive polymers such as polyaniline, polypyrrole, and polythiophene, but the present invention is not limited to these, and 2 or more kinds of these may be used in combination. Alternatively, the 1 st electrode and the 2 nd electrode may be formed of fine wires made of a metal such as gold, silver, copper, aluminum, nickel, or titanium, or an alloy thereof. The 1 st electrode may be provided with an auxiliary electrode (1 st auxiliary electrode), and the 2 nd electrode may be provided with an auxiliary electrode (2 nd auxiliary electrode). The auxiliary electrode can be made of a metal such as gold, silver, copper, aluminum, nickel, or titanium, or an alloy thereof, or can be formed using a silver paste or a copper paste. The auxiliary electrodes (1 st auxiliary electrode and 2 nd auxiliary electrode) are required to have lower resistance than the 1 st electrode and the 2 nd electrode. The 1 st electrode, the 2 nd electrode, and the auxiliary electrodes (the 1 st auxiliary electrode and the 2 nd auxiliary electrode) can be formed by various physical vapor deposition methods (PVD methods) such as vacuum deposition method and sputtering method, various chemical vapor deposition methods (CVD method), various coating methods, various printing methods, and the like, and patterning can be performed by any method such as etching method, lift-off method, method using various masks, and the like.

The structure in which one of the 1 st substrate and the 2 nd substrate also serves as a light guide plate (constituting an optical device, described later) can be adopted, and this structure can reduce the weight of the entire display device without making a user (observer) of the display device feel uncomfortable. One of the 1 st substrate and the 2 nd substrate may be thinner than the other substrate. In the display device including the light control device, the size and the position of the actual light control region of the light control device may be determined based on a signal for displaying an image in the image forming apparatus. The size of the light modulating device may be the same size as the optical device, may be larger, or may be smaller. In short, the 2 nd deflection unit (which is a virtual image forming region, described later) may be located within the orthographic image of the light control device.

In some cases, the light control device can be detachably disposed. In order to detachably dispose the light control device, for example, the light control device may be attached to, for example, a frame using screws made of transparent plastic, or the light control device may be engaged with a groove cut in the frame, or the light control device may be attached to the frame by attaching a magnet to the frame, or the light control device may be fitted to a sliding portion provided in the frame. Alternatively, at least one of the 1 st substrate and the 2 nd substrate may be attached to, for example, a frame. Alternatively, the light control device may be attached to the optical device. That is, the light control device may be attached to the optical device in a close contact state or may be attached to the optical device with a gap therebetween. In this case, one of the light guide plate and the substrate constituting the light control device may be sealed and bonded at an outer edge portion by a sealing member. As the sealing member, various resins such as epoxy resin, urethane resin, acrylic resin, vinyl acetate resin, olefin thiol resin, silicone resin, modified polymer resin, and the like, thermosetting type, photo-curing type, moisture curing type, anaerobic curing type, and the like can be used. However, the present invention is not limited to these examples. The optical device and the light control device may be arranged in this order from the observer side, or the light control device and the optical device may be arranged in this order. The connector may be attached to the light control device (specifically, the connector may be attached to the 1 st electrode or the 2 nd electrode), and the light control device may be electrically connected to a control unit (for example, may be included in a control device for controlling the image forming apparatus) for controlling a light shielding rate (light transmittance) of the light control device through the connector and the wiring.

The maximum light transmittance of the light control device may be 50% or more and the minimum light transmittance of the light control device may be 30% or less. The upper limit value of the maximum light transmittance of the light control device may be 99%, and the lower limit value of the minimum light transmittance of the light control device may be 1%. Here, at

(light transmittance) ═ 100 (%) - (light-shielding rate)

The relationship (2) of (c).

When the light blocking ratio of the virtual image projection region of the light control device including the projection image onto the virtual image of the light control device is "1" during the operation of the light control device, the light blocking ratio of the other region of the light control device may be "1" or may be, for example, 0.95 or less. Alternatively, the light blocking ratio of the other region of the light control device may be set to, for example, 30% or less. On the other hand, the light blocking ratio of the virtual image projection region of the light control device can be set to 35% to 99%, for example, 80%, during operation of the light control device. In this way, the light shielding rate of the virtual image projection area may be constant or may be changed according to the illuminance of the environment in which the display device is placed.

In the display device and the like of the present disclosure, the light shielding rate may be changed gradually (that is, may be changed continuously), and may be changed in a stepwise manner, or may be changed continuously or stepwise from a constant value depending on the arrangement state and shape of the electrodes. That is, the light control device may be set to a state in which the color is gradually changed, and may be set to a state in which the color is continuously or stepwise changed from the state in which the color is changed to a constant color. The light shielding rate can be controlled by the voltage applied to the 1 st electrode and the 2 nd electrode. The potential difference between the 1 st electrode and the 2 nd electrode may be controlled, or the voltage applied to the 1 st electrode and the voltage applied to the 2 nd electrode may be independently controlled. In the case of adjusting the light shielding rate, the test pattern may be displayed on the optical device.

The light control device and the like of the present disclosure further include an illuminance sensor (or 2 nd illuminance sensor) that measures illuminance of an environment in which the display device is placed, and the control unit can start coloring and decoloring of the light control device and can also set the light transmittance according to a measurement result of the illuminance sensor (or 2 nd illuminance sensor). Alternatively, the light control device may further include a switch or the like that can be operated by an observer, and the control unit may start coloring or decoloring of the light control device and may set the light transmittance according to the operation of the switch or the like by the observer. Alternatively, for example, the display device may further include a microphone, and the start of coloring and the start of decoloring of the light control device may be controlled by voice input through the microphone. Specifically, the start of coloring and the start of decoloring of the light control device may be controlled based on an instruction of a natural voice of the observer. Alternatively, the display device may further include an infrared ray incident/emitting device, and the infrared ray incident/emitting device may control the start of coloring and the start of decoloring of the light control device. Specifically, the start of coloring and the start of decoloring of the light control device may be controlled by detecting blinking of the observer by the infrared light incident and emitting device. Alternatively, in the image display device and the display device of the present disclosure, the control unit may start coloring and decoloring of the light control device and may set the light transmittance in synchronization with start of image formation or end of image formation in the image forming device.

As described above, the display device of the present disclosure can be configured as follows: the display device is further provided with an illuminance sensor (ambient illuminance measurement sensor) for measuring the illuminance of the environment in which the display device is placed, and the light blocking rate of the light control device is controlled on the basis of the measurement result of the illuminance sensor (ambient illuminance measurement sensor). Alternatively, the following method can be adopted: the image forming apparatus further includes an illuminance sensor (ambient illuminance measurement sensor) for measuring illuminance of an environment in which the display device is placed, and the brightness of the image formed by the image forming apparatus is controlled based on a measurement result of the illuminance sensor (ambient illuminance measurement sensor). These means may also be combined.

Alternatively, the display device of the present disclosure may be configured as follows: the lighting control device further includes a 2 nd illuminance sensor (for convenience, may be referred to as a "transmitted light illuminance measurement sensor") for measuring illuminance based on light transmitted through the lighting control device from an external environment, and the light blocking ratio of the lighting control device is controlled based on a measurement result of the 2 nd illuminance sensor (transmitted light illuminance measurement sensor). Alternatively, the following method can be adopted: the image forming apparatus further includes a 2 nd illuminance sensor (transmitted light illuminance measuring sensor) for measuring illuminance based on light transmitted through the light control device from an external environment, and the luminance of an image formed by the image forming apparatus is controlled based on a measurement result of the 2 nd illuminance sensor (transmitted light illuminance measuring sensor). It is desirable to arrange the 2 nd illuminance sensor (transmitted light illuminance measurement sensor) closer to the observer than the optical device. At least 2 of the 2 nd illuminance sensors (transmitted light illuminance measuring sensors) may be arranged to measure the illuminance based on light passing through a portion with a high light blocking ratio and to measure the illuminance based on light passing through a portion with a low light blocking ratio. These means may also be combined. Further, these methods may be combined with a method of performing control based on the measurement result of the illuminance sensor (ambient illuminance measurement sensor).

The illuminance sensor (ambient illuminance measurement sensor, transmitted light illuminance measurement sensor) may be a known illuminance sensor, and the illuminance sensor may be controlled by a known control circuit.

The light transmittance (light blocking ratio) can be manually controlled and adjusted by the observer observing the brightness of light passing through the light control device and the optical device and operating a switch or the like (specifically, a switch, a button, a dial, a slider, a knob, and the like, and the same applies hereinafter) by the observer, or the light blocking ratio can be controlled and adjusted based on the measurement result of a 2 nd illuminance sensor (transmitted light illuminance measurement sensor) measuring illuminance based on light transmitted through the light control device from the external environment. In addition, the control and adjustment of the light transmittance (light shielding rate), specifically, the control of the voltage applied to the 1 st electrode and the 2 nd electrode may be sufficient. At least 2 of the 2 nd illuminance sensors (transmitted light illuminance measuring sensors) may be arranged to measure the illuminance based on light passing through a portion with a high light blocking ratio and to measure the illuminance based on light passing through a portion with a low light blocking ratio.

The optical device is of a semi-transmissive type (see-through type). Specifically, at least a portion of the optical device facing the eyeball (pupil) of the observer is made semi-transmissive (see-through), and the external view can be observed through the portion of the optical device and the light control device. The term "semi-transmissive" does not mean that 1/2 (50%) of incident light is transmitted or reflected, but means that a part of incident light is transmitted and the rest is reflected. The display device may include 1 image display device (monocular type) or 2 image display devices (binocular type). In the case where 2 image display devices are provided, the light blocking ratio in one light modulation device and the light blocking ratio in the other light modulation device can be equalized by adjusting the voltages applied to the 1 st electrode and the 2 nd electrode in each of the one light modulation device and the other light modulation device. The light blocking ratio in one light control device and the light blocking ratio in the other light control device can be controlled based on, for example, the measurement result of the 2 nd illuminance sensor (transmitted light illuminance measurement sensor) that measures the illuminance of light transmitted through the light control device from the external environment, or can be manually controlled and adjusted by an observer who observes the brightness of light that has passed through one light control device and the optical device and the brightness of light that has passed through the other light control device and the optical device, and operates a switch or the like. In the case of adjusting the light shielding rate, the test pattern may be displayed on the optical device.

In the light control device of the present disclosure including the preferred embodiments and configurations described above, the light control device can be bent, and thus the light control device can be easily and reliably attached to the image display device or the display device.

Further, when a light modulation layer constituting a light modulation device is formed of an electrochromic material and the transmittance of light is changed by applying a color change of a substance generated by an oxidation-reduction reaction of the electrochromic material, there occurs a phenomenon that the color change does not occur in the light modulation layer when moisture is not present inside the light modulation layer. Therefore, in the light control device and the like of the present disclosure including the preferred embodiments described above, for example, the following embodiments can be provided: in this case, the 1 st substrate may be disposed closer to the viewer than the 2 nd substrate, and the water retaining member may be disposed at least between the 2 nd electrode and the 2 nd substrate as described above. Further, at least a part of the end (side surface) of the light control device may be configured to include the sealing agent and the water holding member from the 1 st substrate side (that is, at least a part of the end of the light control device may be configured to include a laminated structure of the sealing agent and the water holding member extension portion extending from the water holding member from the 1 st substrate side).

Further, the following method can be adopted: the 2 nd electrode is formed on the 1 st substrate from the light modulation layer and is separated from the 1 st electrode, and the moisture holding member covers at least the 2 nd electrode and the light modulation layer.

The resin constituting the water retaining member may be an acrylic resin, a silicone resin, or a urethane resin. Alternatively, the moisture retaining member may be formed of an ultraviolet curable resin. Alternatively, the moisture retaining member can be made of a material called OCA (Optical Clear Adhesive). Alternatively, the water retaining member may be made of at least 1 material selected from the group consisting of an epoxy resin, a polyethylene resin such as polyvinyl alcohol or polyvinyl butyral, a water-containing gel, and a porous material. As the water-containing gel, for example, a mixture of sodium polyacrylate and polyethylene glycol having a dendritic group at the terminal can be exemplified, and as the porous material, silica or the like surface-modified with an organic silane compound can be exemplified. The "water-holding member" may be alternatively referred to as a proton-supplying member, a transparent adhesive member capable of holding water, or a transparent sealing agent capable of holding water. Although depending on the form of the moisture holding member, for example, when the moisture holding member is in the form of a sheet, the 2 nd substrate and the 2 nd electrode can be bonded together via the moisture holding member, and the 2 nd substrate and the sealing agent can be bonded together, and a thermoplastic ultraviolet-curable moisture holding member can also be used. Alternatively, when the moisture holding member is in a liquid state, the moisture holding member may be applied from the 2 nd electrode to the sealing agent, precured as necessary, and then the 2 nd substrate and the moisture holding member may be stacked together while being pressed as necessary, and the moisture holding member may be cured by ultraviolet rays. Alternatively, depending on the material used, the moisture retaining member may be attached to the sealing agent from the 2 nd electrode by a heat lamination method or the like.

The sealing agent functions as a moisture barrier layer, but a structure in which a part of the sealing agent is composed of an auxiliary electrode may be adopted, and in this case, a structure in which the auxiliary electrode is composed of a1 st auxiliary electrode formed on the 1 st electrode and a 2 nd auxiliary electrode formed on the 2 nd electrode separately from the 1 st auxiliary electrode may be adopted. By providing the auxiliary electrode in this manner, an appropriate voltage can be easily applied to the 1 st electrode and the 2 nd electrode, and the voltage drop in the 1 st electrode or the 2 nd electrode can be suppressed, so that the occurrence of unevenness in coloring of the light control device can be reduced. The same applies to the following.

Alternatively, the sealing agent may be formed of a resin, and in this case, the young's modulus of the resin forming the sealing agent may be 1 × 10 ⁷ Pa or less, and in these cases, an auxiliary electrode may be provided inside a part of the sealing agent. Here, the auxiliary electrode may be configured to include a1 st auxiliary electrode formed on the 1 st electrode and a 2 nd auxiliary electrode formed on the 2 nd electrode separately from the 1 st auxiliary electrode. Examples of the resin constituting the sealing agent include various resins such as thermosetting type, photocurable type, moisture curable type, anaerobic curable type and the like, and examples thereof include acrylic resins, urethane resins, silicone resins, fluorine resins, vinyl acetate resins, olefin thiol resins, modified polymer resins, polyimide resins and the likeAnd 1 resin selected from the group consisting of epoxy resins. When the sealing agent is made of a resin, an inorganic filler such as silica or alumina may be added to the resin.

Alternatively, the sealing agent may be configured to include a convex portion provided at the edge of the first substrate 1, and in this case, the auxiliary electrode may be provided inside a part of the sealing agent. Here, the auxiliary electrode may be configured to include a1 st auxiliary electrode formed on the 1 st electrode and a 2 nd auxiliary electrode formed on the 2 nd electrode separately from the 1 st auxiliary electrode. The convex portion on the edge portion of the 1 st substrate can be formed by hot stamping the edge portion of the 1 st substrate using, for example, a hot stamping apparatus, or can be formed by various physical vapor deposition methods (PVD methods), various chemical vapor deposition methods (CVD methods), or various printing methods.

The cross-sectional shape of the sealing agent may be narrowed as the sealing agent approaches the 2 nd substrate. By forming the sealing agent in such a shape in cross section, when the water holding member is disposed at least on the 2 nd electrode and the water holding member extending portion extending from the water holding member is disposed on the sealing agent, the problem of air bubbles being generated and being mixed into the water holding member can be avoided. The cross-sectional shape of the sealing agent can be formed by various methods such as formation of a sealing agent by a printing method and formation of a sealing agent by a sputtering method using a metal mask.

Further, the young's modulus of the material (specifically, resin) constituting the moisture retaining member is desirably 1 × 10 ⁶ Pa or less can thereby absorb various steps occurring inside the light control device, and also can reduce variations in the thickness of the water holding member in the central portion of the light control device and variations in the thickness of the extension portion of the water holding member (that is, can achieve uniform distance between the 1 st substrate and the 2 nd substrate as a whole), and as a result, can prevent the occurrence of degradation in visibility. Specifically, it is possible to suppress the occurrence of distortion or deviation in the external image when the external environment is observed by the light control device.

The moisture holding member is disposed at least on the 2 nd electrode, and the moisture holding member extending portion extending from the moisture holding member is disposed on the sealing agent, and specifically, for example, the moisture holding member may be bonded or attached to the 2 nd electrode, and the moisture holding member extending portion may be bonded or attached to the sealing agent. The 2 nd substrate may be disposed on the moisture holding member and the moisture holding member extension portion, and specifically, for example, the 2 nd substrate may be bonded or adhered to the moisture holding member and the moisture holding member extension portion.

The region in which the value of the light blocking ratio is increased in the light control device may be the entire region of the light control device or may be a region of a part of the light control device. That is, the light blocking ratio of the region of the light control device that faces the region of the 2 nd deflection unit (for example, a region of a part of the 2 nd deflection unit described later) where the virtual image is actually formed may be controlled. In other words, when a virtual image is formed in a part of the virtual image forming region from light emitted from the image forming apparatus, the light control apparatus may be controlled such that the light blocking rate of the virtual image projection region of the light control apparatus (the region of the light control apparatus corresponding to the virtual image forming region in the optical apparatus) including a projection image of the virtual image to the light control apparatus is higher than the light blocking rate of the other region of the light control apparatus. Further, the following method can be adopted: in the light control device, the position of the virtual image projection region is not fixed but varies depending on the formation position of the virtual image, and the number of virtual image projection regions also varies depending on the number of virtual images (or the number of a series of virtual image groups, the number of virtual image groups that are blocked, and the like).

In the display device of the present disclosure including various preferred embodiments described above (hereinafter, these may be collectively referred to as "the display device of the present disclosure, etc."), the following embodiments can be provided: the frame includes a front mirror (front) portion disposed on the front of the observer, 2 temple (temple) portions rotatably attached to both ends of the front mirror portion via hinges, and a nose pad portion, and the light control device is disposed on the front mirror portion. Alternatively, the optical device may be attached to the front portion of the mirror, and in this case, the light control device may be attached to the optical device. In these cases, the light control device may be fitted to the rim portion with the rim portion (rim) provided at the front portion of the mirror, or the optical device may be fitted to the rim portion. Alternatively, the space between the light control device and the optical device may communicate with the outside. In the display device and the like of the present disclosure, the optical device and the light control device may be arranged in this order from the observer side, or the light control device and the optical device may be arranged in this order.

Examples of the adhesive that can transmit water vapor include adhesives based on nonpolar materials such as silicone-based or ethylene-vinyl alcohol-based copolymers, styrene-based butadiene, and the like, which have high water vapor diffusion properties, and the water permeability of the adhesive can be 2 × 10 g/m ² Day to 1.1X 10 ³ Gram/m ² Day. The moisture permeability can be measured according to JIS K7129: 2008, a test was carried out on a test piece of 50mm × 50mm under conditions of a test temperature of 25 ℃. + -. 0.5 ℃ and a relative humidity of 90. + -. 2%. The measurement was performed using a dry-wet sensor.

In addition, the image display device of the present disclosure including the preferred embodiments described above and the display device of the present disclosure including the preferred embodiments described above can be configured as follows: the optical device includes:

a light guide plate that causes light incident from the image forming apparatus to propagate therein by total reflection and then to be emitted toward an observer;

a1 st deflection unit deflecting light incident on the light guide plate so that the light incident on the light guide plate is totally reflected inside the light guide plate; and

and a 2 nd deflection unit configured to deflect the light propagating through total reflection in the light guide plate so that the light propagating through total reflection in the light guide plate is emitted from the light guide plate.

For convenience, such an optical device will be referred to as "optical device of configuration 1". The virtual image forming region of the optical device is constituted by the 2 nd deflecting unit. The 2 nd deflection unit (virtual image forming region) is located within the projection image of the dimming device. The term "total reflection" means total internal reflection or total reflection inside the light guide plate. Light incident from the image forming device propagates by total reflection inside the light guide plate and then exits toward the observer, and the 2 nd deflecting unit constitutes a virtual image forming region of the optical device. There are cases where the 2 nd deflection unit (virtual image forming region) is located within the projection image of the light control device, and where the light control device is located within the projection image of the 2 nd deflection unit (virtual image forming region).

In the optical device of the 1 st configuration, as described above, the 1 st deflecting means may reflect light incident on the light guide plate, and the 2 nd deflecting means may transmit and reflect light (multiple continuous) propagating by total reflection in the light guide plate. In this case, the 1 st deflection unit may function as a mirror and the 2 nd deflection unit may function as a semi-transmissive mirror. For convenience, such an optical device of configuration 1 will be referred to as "optical device of configuration 1-a".

In the optical device of the 1 st-a structure, the 1 st deflecting means may be made of, for example, a metal containing an alloy, and may be composed of a light reflecting film (one kind of mirror) for reflecting light incident on the light guide plate, and a diffraction grating (for example, a hologram diffraction grating film) for diffracting light incident on the light guide plate. Alternatively, the 1 st deflecting means may be constituted by, for example, a multilayer laminated structure in which a plurality of dielectric laminated films are laminated, a half mirror, or a polarization beam splitter. The 2 nd deflection unit may be a multilayer laminated structure in which a plurality of dielectric laminated films are laminated, a half mirror, a polarization beam splitter, or a hologram diffraction grating film. Further, the 1 st deflecting means and the 2 nd deflecting means are disposed inside the light guide plate (embedded inside the light guide plate), but in the 1 st deflecting means, the parallel light incident on the light guide plate is reflected or diffracted so that the parallel light incident on the light guide plate is totally reflected inside the light guide plate. On the other hand, in the 2 nd deflection unit, parallel light propagating through total reflection inside the light guide plate is reflected or diffracted (a plurality of times) and exits from the light guide plate as parallel light. In some cases, one of the 1 st deflecting unit and the 2 nd deflecting unit may be disposed on the outer surface of the light guide plate.

Alternatively, the 1 st deflecting means may diffract light incident on the light guide plate, and the 2 nd deflecting means may diffract light propagating through total reflection in the light guide plate a plurality of times. In this case, the 1 st deflecting means and the 2 nd deflecting means may be configured by diffraction grating elements, and the following configuration may be adopted: the diffraction grating elements are constituted by reflection type diffraction grating elements, or transmission type diffraction grating elements, or one of the diffraction grating elements is constituted by reflection type diffraction grating elements, and the other diffraction grating element is constituted by transmission type diffraction grating elements. As the diffraction grating element, a volume hologram diffraction grating can be cited. The volume hologram diffraction grating is a hologram diffraction grating that diffracts and reflects only the +1 st order diffracted light. The 1 st deflecting unit composed of a hologram diffraction grating is sometimes referred to as a "1 st diffraction grating member" for convenience, and the 2 nd deflecting unit composed of a hologram diffraction grating is sometimes referred to as a "2 nd diffraction grating member" for convenience. For convenience, the optical device of the 1 st configuration is referred to as an "optical device of the 1 st-B configuration". The interference fringes of the hologram diffraction grating layer extend substantially in the Y direction. Here, in the light guide plate, the X direction is a longitudinal direction (horizontal direction) of the light guide plate, the Y direction is a width direction (height direction, vertical direction) of the light guide plate, and the Z direction is a thickness direction of the light guide plate.

In the optical device of the 1 st to the 3 rd configuration, the 3 rd deflecting means may be provided to which the light emitted from the 1 st deflecting means is incident. Further, the light emitted from the 3 rd deflecting means enters the 2 nd deflecting means. Here, the 1 st deflection unit, the 2 nd deflection unit, and the 3 rd deflection unit are formed of volume hologram diffraction gratings, and the wave number vector obtained when the wave number vector of the 1 st deflection unit is projected on the light guide plate is k ^v ₁ Wave number vector to be possessed at 2 nd deflection unitThe wave number vector obtained when the light is projected on the light guide plate is k ^v ₂ K represents a wave number vector obtained when the wave number vector of the 3 rd deflection unit is projected on the light guide plate ^v ₃ When it is preferable to satisfy

k ^v ₁ +k ^v ₂ +k ^v ₃ ＝0。

With the image display device in the display device and the like of the present disclosure, monochrome (for example, green and blue) image display can be performed. In this case, for example, the following configuration can be adopted: the view angle is divided into two (more specifically, divided into two, for example), for example, and the 1 st deflecting unit is formed by stacking 2 diffraction grating members corresponding to each of the two divided view angle groups. Alternatively, the following configuration can be adopted: in order to cope with diffraction reflection of P types of light having different wavelength bands (or wavelengths) of P types (for example, 3 types of wavelength bands of red, green, and blue, P is 3), a1 st diffraction grating member or a 2 nd diffraction grating member is formed by laminating P layers of diffraction grating layers including hologram diffraction gratings in order to display a color image. Interference fringes corresponding to 1 wavelength band (or wavelength) are formed in each diffraction grating layer. Alternatively, the following configuration may be adopted: in order to cope with the diffraction reflection of P types of light having different P types of wavelength bands (or wavelengths), P types of interference fringes are formed in the 1 st diffraction grating member or the 2 nd diffraction grating member composed of 1 diffraction grating layer. Alternatively, for example, the following configuration may be adopted: the 1 st light guide plate is provided with a diffraction grating member comprising a diffraction grating layer including a hologram diffraction grating for diffracting and reflecting light having a wavelength band (or wavelength) of red, the 2 nd light guide plate is provided with a diffraction grating member comprising a diffraction grating layer including a hologram diffraction grating for diffracting and reflecting light having a wavelength band (or wavelength) of green, the 3 rd light guide plate is provided with a diffraction grating member comprising a diffraction grating layer including a hologram diffraction grating for diffracting and reflecting light having a wavelength band (or wavelength) of blue, and the 1 st light guide plate, the 2 nd light guide plate and the 3 rd light guide plate are stacked with a gap therebetween. Alternatively, the following configuration can be adopted: the viewing angle is divided into three, for example, viewing angles, and the 1 st diffraction grating member or the 2 nd diffraction grating member is formed by laminating diffraction grating layers corresponding to the respective viewing angles. Further, by adopting these configurations, it is possible to increase the diffraction efficiency, increase the diffraction acceptance angle, and optimize the diffraction angle when light having each wavelength band (or wavelength) is diffracted and reflected by the 1 st diffraction grating member or the 2 nd diffraction grating member. The protective member is preferably disposed so that the observer does not touch the hologram diffraction grating. The 1 st substrate or the 2 nd substrate constituting the light control device may also serve as a protective member.

The material constituting the 1 st diffraction grating member and the 2 nd diffraction grating member may be a photopolymer material. The materials and basic structures of the 1 st diffraction grating member and the 2 nd diffraction grating member formed of the hologram diffraction grating may be the same as those of the conventional hologram diffraction grating. In the diffraction grating member, interference fringes are formed extending from the inside to the surface, and the method of forming the interference fringes itself may be the same as the conventional method of forming the interference fringes. Specifically, for example, the member constituting the diffraction grating member (for example, photopolymer material) may be irradiated with object light from the 1 st prescribed direction on one side, and the member constituting the diffraction grating member may be irradiated with reference light from the 2 nd prescribed direction on the other side, so that interference fringes formed by the object light and the reference light are recorded inside the member constituting the diffraction grating member. By appropriately selecting the 1 st prescribed direction, the 2 nd prescribed direction, and the wavelengths of the object light and the reference light, a desired pitch of the interference fringes and a desired inclination angle (tilt angle) of the interference fringes on the surface of the diffraction grating member can be obtained. The tilt angle of the interference fringes means an angle formed by the surface of the diffraction grating member (or diffraction grating layer) and the interference fringes. In the case where the 1 st diffraction grating member and the 2 nd diffraction grating member are configured by a laminated structure of P diffraction grating layers including hologram diffraction gratings, the P diffraction grating layers may be laminated (bonded) using, for example, an ultraviolet-curable adhesive after the P diffraction grating layers are separately produced for the lamination of such diffraction grating layers. Alternatively, the P-layer diffraction grating layer may be produced by producing 1 diffraction grating layer using a photopolymer material having adhesive properties, and then successively pasting a photopolymer material having adhesive properties on the diffraction grating layer to produce a diffraction grating layer. If necessary, the produced diffraction grating layer may be irradiated with energy rays, so that monomers in the photopolymer material remaining without being polymerized at the time of irradiation with the object light and the reference light of the diffraction grating layer may be polymerized and fixed. Further, the resin composition may be stabilized by heat treatment as necessary.

Alternatively, in the image display device in the display device and the like of the present disclosure, the optical device may be configured by a semi-transmissive mirror into which light emitted from the image forming device is incident and which emits the light toward the pupil of the observer, or may be configured by a Polarization Beam Splitter (PBS). The virtual image forming region of the optical device is constituted by a semi-transmissive mirror or a polarizing beam splitter. The light emitted from the image forming apparatus may be propagated through the air and incident on the semi-transmissive mirror or the polarization beam splitter, and may be propagated through a transparent member such as a glass plate or a plastic plate (specifically, a member made of the same material as that of a light guide plate described later) and incident on the semi-transmissive mirror or the polarization beam splitter. The semi-transmissive mirror or the polarization beam splitter may be attached to the image forming apparatus via the transparent member, or the semi-transmissive mirror or the polarization beam splitter may be attached to the image forming apparatus via a member different from the transparent member. For convenience, such an optical device is referred to as "optical device of configuration 2". The semi-transmissive mirror may be constituted by the 1 st deflection unit in the optical device of the 1 st-a structure, for example, a light reflection film (a kind of mirror) made of metal including an alloy and reflecting light, and a diffraction grating (for example, a hologram diffraction grating film). Alternatively, the optical device may be configured by a prism on which light emitted from the image forming apparatus is incident and which emits the light toward the pupil of the observer.

In the image display device of the display device and the like of the present disclosure including the various preferred embodiments and configurations described above, the image forming device may have a plurality of pixels arranged in a two-dimensional matrix. For convenience, the structure of such an image forming apparatus is referred to as "the image forming apparatus of the 1 st structure".

As the image forming apparatus having the configuration 1, for example, there can be mentioned an image forming apparatus including a reflection type spatial light modulation device and a light source; an image forming device including a transmissive spatial light modulation device and a light source; among image forming apparatuses including light emitting elements such as organic EL (Electro Luminescence) elements, inorganic EL elements, Light Emitting Diodes (LEDs), and semiconductor laser elements, an image forming apparatus including an organic EL light emitting element (organic EL display apparatus), an image forming apparatus including a reflection type spatial light modulation device and a light source, and an image forming apparatus including a light emitting element are preferable. Examples of the spatial light modulation device include a light valve, for example, a transmissive or reflective Liquid Crystal display device such as LCOS (Liquid Crystal On Silicon), and a Digital Micromirror Device (DMD), and examples of the light source include a light emitting element. The reflective spatial light modulation device may be configured by a liquid crystal display device and a polarization beam splitter that reflects a part of light from the light source and guides the reflected light to the liquid crystal display device, and passes a part of the light reflected by the liquid crystal display device and guides the light to an optical device (for example, a light guide plate). Examples of the light emitting element constituting the light source include a red light emitting element, a green light emitting element, a blue light emitting element, and a white light emitting element. Alternatively, white light may be obtained by mixing red light, green light, and blue light emitted from the red light emitting element, the green light emitting element, and the blue light emitting element with a light pipe to make the luminance uniform. Examples of the light-emitting element include a semiconductor laser element, a solid-state laser, and an LED. The number of pixels may be determined according to specifications required for the image display device, and specific values of the number of pixels may be, for example, 320 × 240, 432 × 240, 640 × 480, 854 × 480, 1024 × 768, 1920 × 1080, or the like. In the image forming apparatus of the configuration 1, a diaphragm corresponding to an image emitting portion that emits an image from the image forming apparatus may be disposed at a position of a focal point (focal point on the image forming apparatus side) in front of a lens system (described later).

Alternatively, in the image display device such as the display device of the present disclosure including the preferred embodiments and configurations described above, the image forming apparatus may include a light source and a scanning unit that scans light emitted from the light source to form an image. For convenience, such an image forming apparatus is referred to as "image forming apparatus of structure 2".

The light source in the image forming apparatus according to configuration 2 may be a light emitting element, specifically, a red light emitting element, a green light emitting element, a blue light emitting element, and a white light emitting element, or may be a light pipe that mixes red light, green light, and blue light emitted from the red light emitting element, the green light emitting element, and the blue light emitting element to obtain white light with uniform brightness. Examples of the light-emitting element include a semiconductor laser element, a solid-state laser, and an LED. The number of pixels (dummy pixels) in the image forming apparatus having the configuration 2 may be determined in accordance with specifications required for the image display apparatus, and specific values of the number of pixels (dummy pixels) may be, for example, 320 × 240, 432 × 240, 640 × 480, 854 × 480, 1024 × 768, 1920 × 1080, or the like. In the case of performing color image display and configuring the light source with red, green, and blue light-emitting elements, for example, it is preferable to perform color synthesis using a cross prism. Examples of the scanning unit include a MEMS (Micro Electro Mechanical Systems) mirror and a galvano mirror each having a micromirror capable of rotating in two dimensions, which horizontally and vertically scans light emitted from a light source. In the image forming apparatus of the 2 nd configuration, a MEMS mirror and a galvano mirror, which correspond to an image emitting portion that emits an image from the image forming apparatus, may be disposed at a position of a front focal point (focal point on the image forming apparatus side) of a lens system (described later).

In the image forming apparatus according to the configuration 1 or the image forming apparatus according to the configuration 2, the light beams that are formed into a plurality of parallel beams by the optical system (the optical system that converts the output light into the parallel beams, which may be referred to as a "parallel beam output optical system", specifically, for example, a collimating optical system or a relay optical system) are input to the light guide plate, and it is necessary to store the light wave surface information after being output from the light guide plate via the 1 st deflecting means and the 2 nd deflecting means, based on the light wave surface information when the light beams are input to the light guide plate. To generate a plurality of parallel lights, for example, a light emitting portion of the image forming apparatus may be positioned at a focal length (position) in the parallel light emitting optical system. The parallel light emitting optical system has a function of converting positional information of pixels into angular information in an optical system of the optical device. As the parallel light emitting optical system, a convex lens, a concave lens, a free-form surface prism, a hologram lens, or an optical system having a positive optical power as a whole, which is a combination of these, can be exemplified. The light shielding portion having the opening may be disposed between the parallel light emitting optical system and the light guide plate so that undesired light emitted from the parallel light emitting optical system does not enter the light guide plate.

The light guide plate has 2 parallel surfaces (1 st surface and 2 nd surface) extending in parallel with an axis (a longitudinal direction, a horizontal direction, and an X direction) of the light guide plate. The width direction (height direction, vertical direction) of the light guide plate corresponds to the Y direction. The thickness direction of the light guide plate corresponds to the Z direction. When the surface of the light guide plate on which light is incident is a light guide plate incident surface and the surface of the light guide plate from which light is emitted is a light guide plate exit surface, the light guide plate incident surface and the light guide plate exit surface may be formed by the 1 st surface, or the light guide plate incident surface may be formed by the 1 st surface and the light guide plate exit surface may be formed by the 2 nd surface. The 1 st deflection unit is disposed on the 1 st surface or the 2 nd surface of the light guide plate, and the 2 nd deflection unit is disposed on the 1 st surface or the 2 nd surface of the light guide plate. The interference fringes of the diffraction grating member extend substantially parallel to the Y direction. Examples of the material constituting the light guide plate include optical glass such AS quartz glass and BK7, glass including soda lime glass and white plate glass, and plastic materials (for example, PMMA, polycarbonate resin, a laminated structure of polycarbonate resin and acrylic resin, cycloolefin polymer, amorphous polypropylene resin, and styrene resin including AS resin). The shape of the light guide plate is not limited to a flat plate, and may have a curved shape. As described above, the dimming device may also be bent.

In the display device and the like of the present disclosure, a light blocking member that blocks incident light to the optical device may be disposed in a region of the optical device where light emitted from the image forming apparatus enters. By arranging the light blocking member for blocking the incidence of the external light to the optical device in the region of the optical device on which the light emitted from the image forming apparatus is incident, even if the amount of the external light incident changes due to the operation of the light control device, the external light does not originally enter the region of the optical device on which the light emitted from the image forming apparatus is incident, and therefore, undesirable stray light or the like is not generated, and the image display quality in the display device is not degraded. Preferably, the light blocking member includes a region of the optical device, in which light emitted from the image forming apparatus enters, in a projected image to the optical device.

Alternatively, in the display device and the like of the present disclosure, a light blocking member that blocks the incidence of the external light to the 1 st deflecting unit may be disposed in a region of the 1 st deflecting unit on which the light emitted from the image forming apparatus is incident. By disposing the light blocking member for blocking the incidence of the external light to the light guide plate in the region of the light guide plate on which the light emitted from the image forming apparatus is incident, the external light is not incident on the region of the light guide plate on which the light emitted from the image forming apparatus is incident, and therefore, undesirable stray light or the like is not generated, and the image display quality in the display device is not degraded. Preferably, the light shielding member includes a region of the light guide plate on which light emitted from the image forming apparatus enters, in the orthographic projection image of the light guide plate.

The light blocking member may be disposed apart from the optical device (light guide plate) on a side of the optical device (light guide plate) opposite to a side on which the image forming apparatus is disposed. In the display device having such a configuration, the light shielding member may be made of, for example, an opaque plastic material, and such a light shielding member may be integrally extended from the housing of the image forming apparatus, attached to the housing of the image forming apparatus, integrally extended from the frame, or attached to the frame. Alternatively, the light blocking member may be disposed in a portion of the optical device (light guide plate) opposite to the side where the image forming apparatus is disposed, or the light blocking member may be disposed in the light control device. The light shielding member made of an opaque material may be formed on the surface of the optical device (light guide plate) by PVD method or CVD method, may be formed by printing method, or may be formed by bonding a film, sheet or foil made of an opaque material (plastic material, metal material, alloy material, or the like). Preferably, the light shielding member is configured to include a projected image of the end of the light control device onto the optical device (light guide plate) within the projected image onto the optical device (light guide plate).

In the display device and the like of the present disclosure, the frame may be configured by the mirror front portion disposed on the front of the observer and the 2 temple portions rotatably attached to both ends of the mirror front portion via the hinges as described above. A foot cover portion (tip portion) is attached to the tip portion of each temple portion as necessary. Specifically, for example, the image display device may be attached to the temple portion, and a case in which the image forming device is housed may be attached to the front portion of the mirror on the temple portion side. The image forming apparatus may be mounted (the housing may be mounted) by an appropriate method such as a method using screws. Further, a nose pad portion may be attached to the front portion of the mirror. The front part of the mirror and the 2 temple parts can be integrated. That is, when the entire display device of the present disclosure is viewed, the frame has approximately the same structure and appearance as those of ordinary eyeglasses and sunglasses. That is, when the entire display device and the like of the present disclosure are viewed, the assembly of the frame (including the rim portion) and the nose pad portion has substantially the same structure as that of ordinary eyeglasses or sunglasses. The nose pad portion may have a known structure. The speaker and the earphone part may be attached to the temple part. The material constituting the frame including the nose pad portion may be made of the same material as that constituting ordinary spectacles or sunglasses, such as metal, alloy, plastic, or a combination thereof.

In the display device and the like of the present disclosure, from the viewpoint of ease of design and mounting, it is desirable to provide a mode in which wirings (signal lines, power lines, and the like) from 1 or 2 image forming apparatuses are extended from the terminal portion of the leg portion and the inside of the leg portion to the outside and connected to the control device. Further, the following method can be adopted: each image forming apparatus includes an earphone unit, and an earphone-unit wiring from each image forming apparatus extends from a distal end portion of the leg unit to the earphone unit via the inside of the temple unit and the leg unit. Examples of the earphone unit include an ear type earphone unit and a bayonet type earphone unit. More specifically, the earphone part wiring is preferably routed from the tip part of the toe box part to the rear side of the auricle (concha) and extended to the earphone part. Further, a camera (image pickup device) may be attached to a central portion of the mirror front portion. Specifically, the camera includes, for example, a solid-state imaging element formed of a CCD or CMOS sensor and a lens. The wiring from the camera may be connected to one of the image display devices (or image forming devices) via the mirror front portion, for example, or may be included in a wiring extending from the image display device (or image forming device).

The display device of the present disclosure can be configured to receive a signal for displaying an image on the image display device (a signal for forming a virtual image on an optical device (e.g., a light guide plate)) from the outside. In such an aspect, for example, information and data related to an image displayed on the image display device can be recorded, stored, and stored in a so-called cloud computer or server, and by providing the display device with a communication means such as a mobile phone or a smartphone, or by combining the display device and the communication means, various information and data can be transmitted and received between the cloud computer, the server, and the display device, and a signal based on the various information and data, that is, a signal for displaying an image on the image display device (a signal for forming a virtual image in the optical device) can be received. Alternatively, a signal for displaying an image on the image display device (a signal for forming a virtual image on the optical device) may be stored in the display device. The image displayed on the image display device includes various information and various data. Alternatively, the display device may include a camera (imaging device), an image captured by the camera may be transmitted to the cloud computer or the server via the communication unit, various information and data corresponding to the image captured by the camera may be retrieved from the cloud computer or the server, the retrieved various information and data may be transmitted to the display device via the communication unit, and the image may be displayed on the image display device by the retrieved various information and data.

When an image captured by a camera (imaging device) is transmitted to a cloud computer or a server via a communication unit, the image captured by the camera may be displayed on an image display device and confirmed on an optical device (e.g., a light guide plate). Specifically, the light control device may display the outer edge of the spatial region imaged by the camera in a frame shape. Alternatively, the light blocking ratio of the region of the light control device corresponding to the spatial region imaged by the camera may be set to be higher than the light blocking ratio of the region of the light control device corresponding to the outside of the spatial region imaged by the camera. With such an approach, the spatial region imaged by the camera appears darker to the observer than the outside of the spatial region imaged by the camera. Alternatively, the light blocking ratio of the region of the light control device corresponding to the spatial region imaged by the camera may be set to be lower than the light blocking ratio of the region of the light control device corresponding to the outside of the spatial region imaged by the camera. With such an approach, the spatial region imaged by the camera appears brighter to the observer than outside the spatial region imaged by the camera. Further, this allows the observer to easily and reliably recognize where the camera is shooting the outside.

The position of the region of the light control device corresponding to the spatial region imaged by the camera (imaging device) can be corrected. Specifically, the display device includes, for example, a mobile phone or a smart phone, or the display device and the mobile phone, the smart phone, or the personal computer are combined, whereby the spatial region imaged by the camera can be displayed on the mobile phone, the smart phone, or the personal computer. In addition, when there is a difference between the spatial region displayed on the mobile phone, the smart phone, or the personal computer and the region of the light control device corresponding to the spatial region imaged by the camera, the difference between the spatial region displayed on the mobile phone, the smart phone, or the personal computer and the region of the light control device corresponding to the spatial region imaged by the camera may be eliminated by moving, rotating, or enlarging/reducing the region of the light control device corresponding to the spatial region imaged by the camera using a circuit (which can also be used by the mobile phone, the smart phone, or the personal computer) for controlling the light blocking ratio (light transmittance) of the light control device.

The display device of the present disclosure including the various modifications described above can be used, for example, for reception and display of an electronic mail, display of various information and the like at various sites on the internet, display of various descriptions, signs, symbols, marks, badges, patterns and the like at the time of driving, operation, maintenance, disassembly and the like of an observation target object such as various devices; display of various descriptions, signs, symbols, marks, badges, patterns, and the like relating to an observation target such as a person or an article; displaying a moving image and a still image; display of subtitles for movies and the like; displaying an explanatory sentence and a closed caption related to the video in synchronization with the video; various descriptions (various descriptions at the time of driving, operation, maintenance, and disassembly) relating to objects to be observed in drama, geisha, drama, wild, opera, concert, ballet, various dramas, amusement park (amusement park), art gallery, sightseeing spot, playing spot, sightseeing guide, and the like, and a display of an explanatory sentence or the like for explaining the content or the progress state, the background, and the like, and a display of a closed caption can be used. In the case of a drama, a geisha, an opera, a romance, an opera, a concert, a ballet, various dramas, an amusement park (amusement park), an art gallery, a sightseeing place, a playing place, a sightseeing guide, or the like, it is sufficient to display characters as an image related to an observation target object on a display device at an appropriate timing. Specifically, for example, an image signal is sent to a display device by an operation of an operator or under the control of a computer or the like according to a predetermined schedule or time distribution in accordance with a progress status of a movie or the like or a progress status of a drama or the like, and an image is displayed on the display device. Further, by displaying various descriptions relating to the observation target objects such as various devices, persons, and articles, photographing (imaging) the observation target objects such as various devices, persons, and articles with a camera, and analyzing the contents of the photographing (imaging) in the display device, it is possible to display various descriptions relating to the observation target objects such as various devices, persons, and articles, which have been created in advance, in the display device.

The image signal to the image forming apparatus may include not only an image signal (e.g., character data) but also, for example, luminance data (luminance information) or chrominance data (chrominance information) or both of the luminance data and the chrominance data, which are related to an image to be displayed. The luminance data may be luminance data corresponding to the luminance of a predetermined region including an observation target observed by an optical device (for example, a light guide plate), and the chromaticity data may be chromaticity data corresponding to the chromaticity of a predetermined region including an observation target observed by an optical device. In this way, the control of the luminance (brightness) of the displayed image can be performed by including the luminance data relating to the image, the control of the chromaticity (color) of the displayed image can be performed by including the chromaticity data relating to the image, and the control of the luminance (brightness) and the chromaticity (color) of the displayed image can be performed by including the luminance data relating to the image and the chromaticity data. In the case of luminance data corresponding to the luminance of a predetermined region including an observation target observed by an optical device, the value of the luminance data may be set so that the value of the luminance of the image is increased as the value of the luminance of the predetermined region including the observation target observed by the optical device is increased (that is, so that the image is displayed more brightly). In the case of chromaticity data corresponding to chromaticity of a predetermined region including an observation target object observed by an optical device, the chromaticity data may be set to have a value such that chromaticity of the predetermined region including the observation target object observed by the optical device and chromaticity of an image to be displayed are in a substantially complementary relationship. Complementary colors refer to combinations of colors in a positive relative relationship in a hue circle (color circle). There may be a complementary color such as green for red, purple for yellow, and orange for blue. It can be said that a color with reduced chroma is caused by mixing another color with a certain color at an appropriate ratio to turn white in the case of light and black in the case of an object, but the complementarity of visual effects in the parallel arrangement is different from the complementarity in the mixing. Also called residual color, contrast color, and reverse color. However, the range of complementary color indication is slightly wider than that of a color in which the opposite color directly indicates the complementary color. The combination of complementary colors with each other's colors has a synergistic effect that mutually sets off colors, which is called complementary hue.

For example, a Head Mounted Display (HMD) can be configured using the display device of the present disclosure. Further, the display device can be reduced in weight and size, which can significantly reduce the inconvenience of wearing the display device, and can also reduce the manufacturing cost. Alternatively, the display device and the like of the present disclosure can be applied to a Head Up Display (HUD) provided in a cockpit of a vehicle or an airplane. Specifically, in the HUD in which the virtual image forming region in which the virtual image is formed based on the light emitted from the image forming device is disposed on the front glass of the cockpit or the like of the vehicle or the airplane, or in the HUD in which the combiner having the virtual image forming region in which the virtual image is formed based on the light emitted from the image forming device is disposed on the front glass of the cockpit or the like of the vehicle or the airplane, at least a part of the virtual image forming region or the combiner and the light control device may be overlapped with each other. The display device and the like of the present disclosure can be used as both a camera (image pickup device) and a stereoscopic display device. In this case, the polarizing plate or the polarizing film may be detachably attached to an optical device (for example, a light guide plate) or the polarizing plate or the polarizing film may be bonded to the optical device as necessary. Further, the solar mirror can be configured by the light control device of the present disclosure, and the light control device of the present disclosure can be attached to a window (including not only a window for a house but also a window in any field such as a vehicle).

Example 1

Example 1 relates to a display device (specifically, a head mounted display, HMD) of the present disclosure, and specifically relates to a display device of mode 1 including the optical device of structure 1 (more specifically, the optical device of structure 1-a) and the image forming apparatus of structure 1. Fig. 1A shows a schematic front view of an optical device and a light control device (of which the right eye is used) in a display device of example 1, fig. 1B shows a schematic cross-sectional view along arrow B-B of fig. 1A, fig. 3A shows a schematic cross-sectional view of the same light control device as that along arrow B-B of fig. 1A, and fig. 3B shows a schematic side view of the display device (mainly the right eye) when the display device is viewed from the left eye side. Fig. 4 and 5 are conceptual views of the image display device in the display device of example 1, fig. 6 is a schematic view of the display device of example 1 as viewed from above, and fig. 7 is a schematic view of the display device of example 1 as viewed from the front.

The display device of embodiment 1 or embodiments 2 to 9 described later includes:

a frame 10 to be worn on the head of a viewer 20; and

the

image display devices

100, 200, 300, 400, and 500 are mounted on the frame 10.

The

image display devices

100, 200, 300, 400, and 500 in embodiment 1 or in embodiments 2 to 9 described below include:

image forming apparatuses

111, 211;

optical devices

120, 320, and 520 each having a virtual image forming region in which a virtual image is formed from light emitted from

image forming devices

111 and 211; and

the light control device 700 is disposed to face at least the virtual image forming region, and adjusts the amount of external light incident from the outside.

The display device of the embodiment is specifically a binocular type having 2 image display devices, but may be a monocular type having 1 image display device. Further, the

image forming apparatuses

111 and 211 display monochromatic images, but are not limited thereto.

In addition, in the

image display devices

100, 200, 300, and 400 of example 1 or in examples 2 to 4 and 6 to 9 described later,

includes optical systems (parallel light emitting optical systems) 112 and 254 for converting light emitted from the

image forming apparatuses

111 and 211 into parallel light,

the light beams that have been collimated by the

optical systems

112 and 254 enter the

optical devices

120 and 320, are guided, and are emitted.

The

optical devices

120 and 320 in embodiment 1 or in embodiments 2 to 4 and 6 to 9 described later have the structure 1, and include:

light guide plates

121 and 321 that allow light incident from the

image forming devices

111 and 211 to propagate therein by total reflection and then to be emitted toward the observer 20;

1

st deflection units

130 and 330 deflecting light incident on the

light guide plates

121 and 321 so that the light incident on the

light guide plates

121 and 321 is totally reflected inside the

light guide plates

121 and 321; and

the 2

nd deflection units

140 and 340 deflect light propagating through total reflection inside the

light guide plates

121 and 321 so that the light propagating through total reflection inside the

light guide plates

121 and 321 is emitted from the

light guide plates

121 and 321.

Further, the 2

nd deflection units

140 and 340 constitute a virtual image forming region of the optical device. In addition, the 2 nd deflecting means (virtual image forming region) 140, 340 is located within the projection image of the light control device 700. The 2

nd deflection units

140 and 340 are covered with one of the substrates constituting the light control device 700. The

optical devices

120 and 320 are of a see-through type (semi-transmissive type).

Here, in embodiment 1, the 1 st deflection unit 130 and the 2 nd deflection unit 140 are disposed inside the light guide plate 121. Further, the 1 st deflection unit 130 reflects light incident to the light guide plate 121, and the 2 nd deflection unit 140 transmits and reflects light propagating through total reflection inside the light guide plate 121 for a plurality of times. That is, the 1 st deflection unit 130 functions as a mirror, and the 2 nd deflection unit 140 functions as a semi-transmissive mirror. More specifically, the 1 st deflection unit 130 disposed inside the light guide plate 121 is formed of aluminum (Al) and is formed of a light reflection film (i) that reflects light incident on the light guide plate 121Seed mirror). On the other hand, the 2 nd deflection unit 140 provided inside the light guide plate 121 is composed of a multilayer laminated structure in which a plurality of dielectric laminated films are laminated. The dielectric laminated film is made of, for example, TiO as a high dielectric constant material ₂ Film and SiO as low dielectric constant material ₂ A membrane. A multilayer laminated structure in which a plurality of dielectric laminated films are laminated is disclosed in Japanese patent publication No. 2005-521099. In the drawings, 6 dielectric laminated films are illustrated, but not limited thereto. A sheet made of the same material as the material of the light guide plate 121 is sandwiched between the dielectric laminated film and the dielectric laminated film. In the 1 st deflection unit 130, the parallel light incident on the light guide plate 121 is reflected (or diffracted) so that the parallel light incident on the light guide plate 121 is totally reflected inside the light guide plate 121. On the other hand, in the 2 nd deflection unit 140, the parallel light propagating through total reflection inside the light guide plate 121 is reflected (or diffracted) a plurality of times and exits from the light guide plate 121 toward the pupil 21 of the observer 20 in a parallel light state.

The 1 st deflecting unit 130 may be formed by cutting out the portion 124 where the 1 st deflecting unit 130 of the light guide plate 121 is disposed, providing an inclined surface on which the 1 st deflecting unit 130 is to be formed in the light guide plate 121, vacuum-depositing a light reflecting film on the inclined surface, and then bonding the cut-out portion 124 of the light guide plate 121 to the 1 st deflecting unit 130. The 2 nd deflection unit 140 may be formed by preparing a multilayer laminated structure in which a plurality of layers of the same material (e.g., glass) as the material constituting the light guide plate 121 and a dielectric laminated film (which can be formed by, for example, a vacuum deposition method) are laminated, cutting out the portion 125 where the 2 nd deflection unit 140 of the light guide plate 121 is provided to form a slope, bonding the multilayer laminated structure to the slope, and finishing the outer shape by polishing or the like. In this way, the optical device 120 in which the 1 st deflection unit 130 and the 2 nd deflection unit 140 are provided inside the light guide plate 121 can be obtained.

Here, in embodiment 1, or embodiments 2 to 4 and embodiments 6 to 9 described later, the

light guide plates

121 and 321 made of optical glass or plastic material have 2 parallel surfaces (the 1 st surfaces 122 and 322 and the 2 nd surfaces 123 and 323) extending in parallel to the light propagation direction (X direction) of the total internal reflection of the

light guide plates

121 and 321. The 1

st surface

122, 322 and the 2

nd surface

123, 323 face each other. The parallel light enters from the 1

st surface

122, 322 corresponding to the light incident surface, propagates through total reflection inside, and then exits from the 1

st surface

122, 322 corresponding to the light exiting surface. However, the present invention is not limited to this, and the 2 nd surfaces 123 and 323 may constitute light incident surfaces, and the 1 st surfaces 122 and 322 may constitute light emitting surfaces.

In example 1 or example 3 to be described later, the image forming apparatus 111 constituting the image display apparatus 100 is an image forming apparatus having the 1 st configuration, and has a plurality of pixels arranged in a two-dimensional matrix. Specifically, as shown in fig. 4, the image forming apparatus 111 includes a reflective spatial light modulation device 150 and a light source 153 formed of a light emitting diode that emits white light. Each image forming apparatus 111 is entirely housed in a casing 113 (shown by a dashed-dotted line in fig. 4), and an opening (not shown) is provided in the casing 113, and light is emitted from an optical system (a parallel light emitting optical system, a collimating optical system) 112 through the opening. The reflective spatial light modulation device 150 includes a liquid crystal display device (LCD)151 configured by LCOS as a light valve, and a polarization beam splitter 152 that reflects a part of light from a light source 153 to guide to the liquid crystal display device 151 and passes a part of light reflected by the liquid crystal display device 151 to guide to the optical system 112. The liquid crystal display device 151 includes a plurality of (for example, 640 × 480) pixels (liquid crystal cells) arranged in a two-dimensional matrix. The polarization beam splitter 152 has a known structure and configuration. Unpolarized light emitted from the light source 153 impinges on the polarization beam splitter 152. In the polarization beam splitter 152, the P-polarized light component passes through and exits the system. On the other hand, the S-polarized light component is reflected by the polarization beam splitter 152, enters the liquid crystal display device 151, is reflected inside the liquid crystal display device 151, and is emitted from the liquid crystal display device 151. Here, of the light emitted from the liquid crystal display device 151, a large amount of P-polarized light components are included in the light emitted from the pixel displaying "white", and a large amount of S-polarized light components are included in the light emitted from the pixel displaying "black". Therefore, the P-polarized light component is guided to the optical system 112 by the polarization beam splitter 152 within the light that is emitted from the liquid crystal display device 151 and impinges on the polarization beam splitter 152. On the other hand, the S-polarized light component is reflected by the polarization beam splitter 152 and returned to the light source 153. The optical system 112 is composed of, for example, a convex lens, and the image forming device 111 (more specifically, the liquid crystal display device 151) is disposed at a focal length (position) in the optical system 112 in order to generate parallel light.

Alternatively, as shown in fig. 5, the image forming apparatus 111 'is constituted by an organic EL display apparatus 150'. The image emitted from the organic EL display device 150' is collimated by the convex lens 112 and directed toward the light guide plate 121. The organic EL display device 150' includes a plurality of (for example, 640 × 480) pixels (organic EL elements) arranged in a two-dimensional matrix.

The frame 10 is composed of a front mirror portion 11 disposed on the front side of the

observer

20, 2 temple portions 13 rotatably attached to both ends of the front mirror portion 11 via hinges 12, and a foot cover portion (also referred to as tip, ear rest, or ear pad) 14 attached to the tip end portion of each temple portion 13. In addition, a nose pad portion 10' is mounted. That is, the frame 10 and the assembly of the nose pad portion 10' have substantially the same structure as that of a general eyeglass. Each housing 113 is detachably attached to the temple portion 13 by an attachment member 19. The frame 10 is made of metal or plastic. Each housing 113 may be detachably attached to the temple portion 13 by an attachment member 19. Further, each housing 113 is shown as being attached to the inside of the temple portion 13, but may be attached to the outside of the temple portion 13.

Further, a wiring (signal line, power supply line, etc.) 15 extending from the image forming apparatus 111 extends from the distal end portion of the leg unit 14 to the outside via the inside of the temple unit 13 and the leg unit 14, and is connected to a control apparatus (including the control unit 30) 18. Each of the

image forming apparatuses

111A and 111B includes a headphone portion 16, and a wiring 16' for the headphone portion extending from each of the

image forming apparatuses

111A and 111B extends from a distal end portion of the foot cover portion 14 to the headphone portion 16 via the inside of the temple portion 13 and the foot cover portion 14. More specifically, the earphone part wiring 16' extends from the tip end part of the toe box part 14 to the rear side of the auricle (concha) to the earphone part 16. With such a configuration, the earphone unit 16 and the earphone unit wiring 16' are not arranged in a disorder, and a neat display device can be provided.

A camera 17 including a solid-state imaging element including a CCD or CMOS sensor and a lens (not shown) is mounted on the central portion of the mirror front portion 11 by an appropriate mounting member (not shown) as necessary. The signal from the camera 17 is sent to the control device 18 via a wiring (not shown) extending from the camera 17.

Here, in the display device of embodiment 1 or embodiments 2 to 9 to be described later, the light control device 700 is disposed in the mirror front portion 11. The

optical devices

120 and 320 are attached to the light control device 700. The mirror front 11 has a mirror rim 11 ', and the dimming device 700 is embedded in the mirror rim 11'. The

optical devices

120 and 320 and the light control device 700 are arranged in this order from the observer side, but the light control device 700 and the

optical devices

120 and 320 may be arranged in this order.

In embodiment 1 or embodiments 2 to 9 described later, the

optical devices

120, 320, and 520 overlap at least a part of the light control device 700 which is one type of light shutter. Specifically, in the example shown in fig. 1A and 1B, the

optical devices

120, 320, and 520 overlap a part of the light control device 700. However, the present invention is not limited to this, and the

optical devices

120, 320, and 520 may be overlapped with the light control device 700. That is, the external shapes of the

optical devices

120, 320, and 520 (more specifically, the

light guide plates

121 and 321 constituting the optical devices) and the

light guide members

602, 612, and 622 may be the same as the external shape of the light control device 700. Fig. 2A shows a schematic front view of the optical device and the light control device in such a manner (i.e., a modification of the display device of embodiment 1), and fig. 2B shows a schematic cross-sectional view of the optical device and the light control device along an arrow B-B of fig. 2A. In this modification, a gap is provided between the light control device 700 and the

light guide plates

121 and 321, and the light control device 700 and the

light guide plates

121 and 321 are bonded to each other at the outer peripheral portion with an adhesive 719D. The same may be said in the embodiments described below. In addition, the outer edge portions of the

light guide plates

121 and 321 are thus shielded by the mirror ring 11', which will be described later, and the outer edge portions of the

light guide plates

121 and 321 are not visible. Here, the nose side of the observer 20 is referred to as the inner side, the ear side is referred to as the outer side, and a region of the light control device 700 facing the virtual image forming region (2 nd deflection unit 140, 340) of the optical device is referred to as a virtual image forming region facing region 701.

In the display device of embodiment 1 or embodiments 2 to 9 described later, the light control device 700 includes:

the 1 st electrode 712A;

a 2 nd electrode 712B facing the 1 st electrode 712A;

a light modulation layer 716 sandwiched between the 1 st electrode 712A and the 2 nd electrode 712B; and

a control section 30 for controlling the coloring/decoloring of the light adjusting layer 716,

the control unit 30 includes a secondary battery 31, a control circuit 32, and a capacitor (also referred to as a capacitor, specifically, for example, an electric double layer capacitor, also referred to as a super capacitor or an ultra capacitor) 33,

the control part 30 controls

(A) Charging of the capacitor 33 by the secondary battery 31, an

(B) The voltage is applied to the 1 st electrode 712A and the 2 nd electrode 712B based on the discharge of the capacitor 33 when the light control layer 716 is colored or decolored.

Further, the control section 30 controls

(C) A predetermined time (T) elapses from the start of coloring or decoloring of the light control layer 716 ₀ ) The voltage is applied to the 1 st electrode 712A and the 2 nd electrode 712B by the secondary battery 31.

The 1 st electrode 712A and the 2 nd electrode 712B are connected to the control unit 30 via a connector not shown. In the example shown in fig. 11A, the number of the capacitors 33 is 1, but a plurality of capacitors 33 connected in parallel may be used to secure a desired capacitance.

In addition, a predetermined time T elapses from the start of coloring of the dimming layer 716 ₀ ' thereafter, voltage application to the 1 st electrode 712A and the 2 nd electrode 712B by the secondary battery 31 is performed, but a predetermined time (coloring/predetermined time) T may be elapsed ₁ ' thereafter, the secondary battery 31 stops the 1 st electrode 712A and the 2 nd electrodeA voltage is applied to the pole 712B. Similarly, a predetermined time T elapses from the decoloring of the light control layer 716 ₀ "thereafter, voltage application to the 1 st electrode 712A and the 2 nd electrode 712B is performed by the secondary battery 31, but a predetermined time (decoloring/predetermined time) T may be elapsed ₁ "thereafter, the voltage application to the 1 st electrode 712A and the 2 nd electrode 712B by the secondary battery 31 is stopped. In some cases, the predetermined time T may be elapsed from the decoloring of the light control layer 716 ₀ "thereafter, the voltage application to the 1 st electrode 712A and the 2 nd electrode 712B by the secondary battery 31 is stopped. In addition, when the light control layer 716 is colored, the value of the voltage applied to the 1 st electrode 712A and the 2 nd electrode 712B based on the discharge of the capacitor 33 and the predetermined time T elapsed from the start of coloring of the light control layer 716 ₀ The value of the voltage applied to the 1 st electrode 712A and the 2 nd electrode 712B by the secondary battery 31 after' can be set to the same value, and the value of the light transmittance of the light adjustment layer 716 can be defined by this voltage. The predetermined time T can also be set ₀ 、T ₀ ’、T ₀ ", prescribed time (coloring/prescribed time) T ₁ ', predetermined time (erasing/predetermined time) T ₁ "is stored in advance in the control unit 30. Alternatively, the control unit 30 may measure the voltage applied to the 1 st electrode 712A and the 2 nd electrode 712B, and when the voltage applied to the 1 st electrode 712A and the 2 nd electrode 712B reaches a predetermined voltage or a predetermined voltage, the control unit 30 may determine that the predetermined time T has elapsed ₀ 、T ₀ ’、T ₀ ", prescribed time (coloring/prescribed time) T ₁ ', predetermined time (erasing/predetermined time) T ₁ ”。

In addition, in the display device of the embodiment 1 or the embodiments 2 to 9 described later,

the control unit 30 applies a positive potential to one of the 1 st electrode 712A and the 2 nd electrode 712B and a negative potential to the other of the 1 st electrode 712A and the 2 nd electrode 712B during coloring of the light control device,

the control unit 30 applies a voltage having a polarity opposite to that of the light control device at the time of coloring to the 1 st electrode 712A and the 2 nd electrode 712B at the time of decoloring of the light control device. Specifically, for example, a voltage relatively higher than that of the 1 st electrode 712A is applied to the 2 nd electrode 712B during coloring of the light control device, and a voltage relatively higher than that of the 2 nd electrode 712B is applied to the 1 st electrode 712A during decoloring of the light control device.

In example 1 or the display devices according to examples 2 to 9 to be described later, the light control device 700 includes a1 st substrate 711A and a 2 nd substrate 711B facing the 1 st substrate 711A, the 1 st electrode 712A is provided on a facing surface of the 1 st substrate 711A facing the 2 nd substrate 711B, and the 2 nd electrode 712B is provided on a facing surface of the 2 nd substrate 711B facing the 1 st substrate 711A. In the illustrated example, the 1 st substrate 711A faces the viewer 20, but the 2 nd substrate 711B may face the viewer 20.

In addition, in the display device of embodiment 1 or embodiments 2 to 9 described later, the amount of charge for providing a desired light transmittance to the light-adjusting layer 716 at the time of coloring is set to Q ₀ The charge amount of the charged capacitor 33 is represented by Q ₁ A predetermined time T will elapse from the start of coloring or decoloring of the light control layer 716 ₀ The charge amount of the capacitor 33 is Q ₂ To satisfy

0.4<(Q ₁ -Q ₂ )/Q ₀

Preference is given to

1.0≤(Q ₁ -Q ₂ )/Q ₀ ≤10.0

In the embodiment of (1), the controller 30 controls the voltage applied to the capacitor 33 and the 1 st and 2

nd electrodes

712A, 712B. Further, as T ₀ A value of (a) satisfies

T is not less than 0.1 (second) ₀ Less than or equal to 12 (second)

Preference is given to

T is more than or equal to 0.8 (second) ₀ Less than or equal to 4 seconds.

Specifically, although not limited thereto, examples thereof include

Q ₀ 250 millifarad (dimming area 2500 mm) ² Condition (2)

Q ₁ 500 millifarad

Q ₂ At a rate of 250 millifarads,

can also give

T ₀ 4 seconds

T ₀ ' 4 seconds

T ₀ After 2 seconds.

In addition, the effective area of the light control layer 716 is defined as A (mm) ² ) When the capacitance of the capacitor 33 is C (farad), the capacitance satisfies

C/A>1×10 ^-6 [0.000001](F/mm ² )。

Specifically, it is set as

A＝2500mm ²

C-250 millifarads.

In addition, when the light control device is colored or decolored, a constant voltage is applied to the 1 st electrode 712A and the 2 nd electrode 712B from the capacitor (capacitor) 33 and (or) the secondary battery 31 to the 1 st electrode 712A and the 2 nd electrode 712B via the voltage control circuit (regulator) 50. The output voltage from the secondary battery 31 may be higher than a voltage at which damage does not occur in the material constituting the light modulation layer 716, and therefore, the problem of damage occurring in the material constituting the light modulation layer 716 can be avoided by passing through the voltage control circuit 50, but the voltage control circuit 50 may not be necessary.

In example 1 or the display devices of examples 2 to 9 to be described later, when a voltage is applied to the 1 st electrode 712A and the 2 nd electrode 712B, a current flows through the light control layer 716.

The dimming device 700 is composed of one type of light shutter to which a color change of a substance generated by an oxidation-reduction reaction of an electrochromic material is applied. Specifically, the dimming layer 716 comprises an electrochromic material. More specifically, the light modulation layer 716 has WO from the 1 st electrode side ₃ Layer (reduction coloring layer) 713/Ta ₂ O ₅ Layer (electrolyte layer) 714/Ir _X Sn _1-X A laminated structure of an O layer (oxidation coloring layer) 715. WO ₃ The layer 713 develops a color by reduction. In addition, Ta ₂ O ₅ Layer 714 constitutes the solid electrolyte, Ir _X Sn _1-X The O layer 715 is subjected to oxidation color development. A SiN layer or SiO layer is formed between the 1 st electrode 712A and the 1 st substrate 711A ₂ Layer of Al ₂ O ₃ Layer, TiO ₂ And a protective layer 719A made of a layer or a laminated film thereof. By forming the protective layer 719A, the light control device can be provided with ion blocking properties for preventing the passage of ions, water resistance, moisture resistance, and scratch resistance. A base layer 719B is formed between the 2 nd substrate 711B and the 2 nd electrode 712B. The 1 st substrate 711A and the 2 nd substrate 711B are sealed at their outer peripheral portions with a sealing agent 719C made of an ultraviolet curable resin such as an ultraviolet curable epoxy resin, and a thermosetting epoxy resin. The 1 st substrate 711A and the 2 nd substrate 711B are made of PEN (polyethylene naphthalate) resin, PES (polyethersulfone) resin, COP (cycloolefin polymer), colorless and transparent polyimide resin, TAC film, or highly transparent self-adhesive acrylic film, but are not limited thereto. The 1 st electrode 712A and the 2 nd electrode 712B made of a transparent conductive material such as ITO or IZO are not patterned, but are what are called "beta electrodes". The dimmer 700 itself can be made in a known manner.

At a temperature of Ir _X Sn _1-X In the O layer 715, Ir and H ₂ O reaction as iridium hydroxide Ir (OH) _n Are present. When a negative potential is applied to the 1 st electrode 712A and a positive potential is applied to the 2 nd electrode 712B, the secondary electrode Ir _X Sn _1-X O layer 715 towards Ta ₂ O ₅ Protons H of layer 714 ⁺ The electrons are released to the 2 nd electrode 712B, and the next oxidation reaction proceeds, Ir _X Sn _1-X The O layer 715 is colored.

Ir(OH) _n →IrO _X (OH) _n-X (coloring) + X.H ⁺ +X·e ^-

On the other hand, Ta ₂ O ₅ Protons H in layer 714 ⁺ To WO ₃ The electrons move in the layer 713 and are injected from the 1 st electrode 712A into WO ₃ Layer 713, in WO ₃ The subsequent reduction reaction is carried out in layer 713, WO ₃ Layer 713 is colored.

WO ₃ +X·H ⁺ +X·e ^- →H _X WO ₃ (coloring)

In contrast, a positive potential is applied to the 1 st electrode 712A, and a negative potential is applied to the 2 nd electrode 712BAt time of Ir _X Sn _1-X In the O layer 715, the reduction reaction proceeds in the reverse direction to the above direction to decolorize the film, and in WO ₃ The oxidation reaction proceeds in the reverse direction to the above direction in the layer 713, and the color is reduced. In addition, at Ta ₂ O ₅ Layer 714 includes H ₂ O, ionized by applying a voltage to the 1 st and 2

nd electrodes

712A and 712B, and containing protons H ⁺ 、OH ^- The state of the ions contributes to the coloring reaction and the decoloring reaction.

Fig. 8 shows an example of a relationship between the voltage (Δ V) applied between the 1 st electrode 712A and the 2 nd electrode 712B and the light transmittance. In the illustrated example, the light transmittance decreases as the value Δ V of the voltage applied between the 1 st electrode 712A and the 2 nd electrode 712B increases, but when Δ V exceeds 1 volt, the rate at which the light transmittance decreases. In addition, in the case where Δ V is 0.2 volts, it can be recognized that the dimming layer 716 starts coloring.

Fig. 9 shows a graph showing a change in current flowing through the light control layer 716 after the start of coloring in which a constant voltage (Δ V) is applied between the 1 st electrode 712A and the 2 nd electrode 712B constituting the light control device 700 as shown in the upper part of fig. 9, and a graph showing a change in light transmittance in the lower part of fig. 9. Further, a graph showing a change in current flowing through the light control layer 716 in a state after the start of decoloring in which a constant voltage (- Δ V) is applied between the 1 st electrode 712A and the 2 nd electrode 712B constituting the light control device 700 as shown in the upper stage of fig. 10 is shown in the middle stage of fig. 10, and a graph showing a change in light transmittance is shown in the lower stage of fig. 10. Here, the case of example 1 in which the current flowing through the dimming layer 716 is not limited is represented by "a", and the case of limiting the current flowing through the dimming layer 716 to 20 ma is represented by "B" as comparative example 1. In the case of example 1 in which the current flowing through the light control layer 716 is not limited, the voltage application to the 1 st electrode 712A and the 2 nd electrode 712B based on the discharge of the capacitor 33 is performed. After a voltage is applied to the 1 st electrode 712A and the 2 nd electrode 712B in response to discharge of the capacitor 33, a voltage is applied from the secondary battery 31 to the 1 st electrode 712A and the 2 nd electrode 712B.

In the case of comparative example 1 in which the current flowing through the light control layer 716 is limited to 20 ma, a long time is required for coloring and decoloring. On the other hand, in the case of example 1 in which the current flowing through the light control layer 716 is not limited, since the voltage application to the 1 st electrode 712A and the 2 nd electrode 712B is performed by the discharge of the capacitor 33, it is understood that the time required for coloring/decoloring is significantly shortened.

When the light control device 700 performs light control, the polarities of the voltages applied to the 1 st electrode 712A and the 2 nd electrode 712B need to be inverted in coloring and decoloring. In order to obtain a target light transmittance, it is necessary to change (control or set) the voltage applied between the 1 st electrode 712A and the 2 nd electrode 712B. In order to rapidly change the light transmittance, a large current needs to be passed between the 1 st electrode 712A and the 2 nd electrode 712B at the start of coloring or at the start of decoloring. When a large current flows between the 1 st electrode 712A and the 2 nd electrode 712B, for example, the voltage supplied to the image forming apparatus cannot be temporarily reduced, and the operation of the entire display apparatus becomes unstable.

Fig. 11A and 13 show circuit diagrams of the control unit 30. Fig. 13 is a circuit diagram of a secondary battery control unit 32A as a part of a control circuit 32 constituting the control unit 30. The control circuit 32 includes:

a current limiting circuit that limits a current at the time of discharge of the secondary battery 31; and

the voltage control circuit (regulator) 50 controls the voltages applied to the 1 st electrode 712A and the 2 nd electrode 712B from the capacitor 33 and the secondary battery.

Here, the current limiting circuit is included in the secondary battery control unit 32A. In the illustrated example, the number of the capacitors 33 is 1, but a plurality of capacitors 33 connected in parallel may be used to secure a desired capacitance.

The control circuit 32 includes a1 st switching unit 41 and a 2 nd switching unit 42. In addition, in the control unit 30, the positive electrode terminal 1031 and the negative electrode terminal 1032 of the secondary battery control unit 32A are connected to the 1 st switching unit 41 constituting the control circuit 32, and both ends of the capacitor 33 are also connected to the 1 st switching unit 41. Further, the light control device 700 is also connected to the 1 st switching unit 41 via the 2 nd switching unit 42. The polarity of the voltage applied to the 1 st electrode 712A and the 2 nd electrode 712B can be switched by switching the 2 nd switching unit 42.

The positive electrode terminal 1031 and the negative electrode terminal 1032 of the secondary battery control section 32A are also connected to an image forming apparatus or the like constituting a display device, and the image forming apparatus or the like is driven by the secondary battery 31. Here, secondary battery 31 is constituted by battery cell (assembled battery) 1001 shown in fig. 13.

In the light control device of the embodiment, the capacitor 33 is charged by the secondary battery 31 at a limited current value except when the capacitor 33 is discharged. When the coloring or decoloring of the light control device 700 is started, the voltage is applied to the 1 st electrode 712A and the 2 nd electrode 712B by the discharge of the capacitor 33. When the capacitor 33 is discharged and the voltage applied to the 1 st electrode 712A and the 2 nd electrode 712B is decreased, that is, when a predetermined time (T) has elapsed from the start of coloring or decoloring of the light control device 700 ₀ ) After that, voltage application to the 1 st electrode and the 2 nd electrode by the secondary battery 31 is performed. Fig. 31 shows a flow of the operation of the above light control device.

Specifically, in the 1 st switching unit 41, when the capacitor 33 is charged by the secondary battery 31 at the limited current value, the switching unit SW is turned on ₂ The switch part SW is set to the connection state ₁ 、SW ₃ The cutting state is established. If the charging of the capacitor 33 is completed, the switch unit SW is turned on ₂ The cutting state is established. When the coloring or decoloring of the light control device 700 is started, the switch unit SW is turned on ₁ 、SW ₂ The switch section SW is turned off ₃ The capacitor 33 is discharged in the connected state. Further, when discharging capacitor 33, switching unit SW may be set to be turned on when the backflow of current from capacitor 33 to secondary battery control unit 32A is prevented by secondary battery control unit 32A ₁ The connection state is established. Further, a predetermined time (T) elapses from the start of coloring or decoloring of the light control device 700 ₀ ) Then, the switch unit SW is turned on ₁ The switch is set to a connection stateSection SW ₂ 、SW ₃ The cutting state is established.

As shown in fig. 13, secondary battery control unit 32A, which is a part of control circuit 32 constituting control unit 30, includes an exterior member (not shown), a switch unit 1021, a current detection resistor 1014, a temperature detection element 1016, and a controller 1010. The switch unit 1021 includes a charge control switch 1022 and a discharge control switch 1024. The control unit includes a positive electrode terminal 1031 and a negative electrode terminal 1032, and the positive electrode terminal 1031 and the negative electrode terminal 1032 are connected to the positive electrode terminal and the negative electrode terminal of the charger, respectively, during charging to perform charging. In addition, when the display device is used, the positive electrode terminal 1031 and the negative electrode terminal 1032 are connected to the positive electrode terminal and the negative electrode terminal of the display device, respectively, and discharge is performed.

Battery unit 1001 (secondary battery 31) is configured by connecting a plurality of lithium ion batteries 1002 in series and/or in parallel. Fig. 13 shows a case where 6 lithium ion batteries 1002 are connected in 2-parallel 3-series connection (2P3S), but any connection method may be used so that P-parallel q-series connection (where P and q are integers) is used. That is, the lithium ion batteries may be connected in series, in parallel, or in a hybrid form.

The switch unit 1021 includes a charge control switch 1022 and a diode 1023, and a discharge control switch 1024 and a diode 1025, and is controlled by the controller 1010. Diode 1023 has a polarity in a reverse direction to a charging current flowing from positive terminal 1031 to battery cell 1001 and in a forward direction to a discharging current flowing from negative terminal 1032 to battery cell 1001. Diode 1025 has a polarity in the forward direction with respect to the charging current and in the reverse direction with respect to the discharging current. In the example, the switch unit is provided on the plus (+) side, but may be provided on the minus (-) side. The charge control switch 1022 is turned off when the battery voltage becomes the overcharge detection voltage or when the discharge of the capacitor 33 is started, and is controlled by the controller 1010 so that the charge current (or the reverse current) does not flow through the current path of the battery cell 1001. After the charge control switch 1022 is turned off, only discharge is enabled via the diode 1023. When a large current flows during charging or when discharging of capacitor 33 is started, the state is turned off, and controller 1010 controls the charging current (or the reverse current) flowing through the current path of battery cell 1001 so as to be interrupted. When the battery voltage reaches the over-discharge detection voltage, the discharge control switch 1024 is turned off, and is controlled by the controller 1010 so that the discharge current does not flow through the current path of the battery cell 1001. After the discharge control switch 1024 is turned off, only charge is enabled via the diode 1025. When a large current flows during discharge, the discharge state is turned off, and the controller 1010 controls the discharge current flowing through the current path of the battery cell 1001 to be cut off. In this way, the secondary battery control unit 32A also functions as a current limiting circuit that limits a current during discharge of the secondary battery 31.

The temperature detection element 1016 is composed of, for example, a thermistor, and is provided in the vicinity of the battery cell 1001, and the temperature measurement unit 1015 measures the temperature of the battery cell 1001 using the temperature detection element 1016 and sends the measurement result to the controller 1010. The voltage measuring unit 1012 measures the voltage of the battery cell 1001 and the voltages of the lithium ion batteries 1002 constituting the battery cell 1001, performs a/D conversion on the measurement results, and sends the measurement results to the controller 1010. The current measuring unit 1013 measures a current using the current detection resistor 1014, and sends the measurement result to the controller 1010.

The switch control unit 1020 controls the charge control switch 1022 and the discharge control switch 1024 of the switch unit 1021 based on the voltage and the current supplied from the voltage measurement unit 1012 and the current measurement unit 1013. When the voltage of any one of the lithium ion batteries 1002 becomes equal to or lower than the overcharge detection voltage or the overdischarge detection voltage or when a large current rapidly flows, the switch control unit 1020 transmits a control signal to the switch unit 1021 to prevent overcharge, overdischarge, and overcurrent charge and discharge. The charge control switch 1022 and the discharge control switch 1024 may be formed of semiconductor switches such as MOSFETs, for example. In this case, the

diodes

1023 and 1025 are formed by parasitic diodes of the MOSFET. When a p-channel FET is used as the MOSFET, the switch control unit 1020 supplies the control signal DO and the control signal CO to the gate portions of the charge control switch 1022 and the discharge control switch 1024, respectively. The charge control switch 1022 and the discharge control switch 1024 are turned on by a gate potential lower than the source potential by a predetermined value or more. That is, in the normal charging and discharging operations, the control signals CO and DO are set to the low level, and the charge control switch 1022 and the discharge control switch 1024 are set to the on state. For example, when overcharging or overdischarging occurs, the control signals CO and DO are set to the high level, and the charge control switch 1022 and the discharge control switch 1024 are set to the off state.

The Memory 1011 is configured by an EPROM (Erasable Programmable Read Only Memory) or the like as a nonvolatile Memory, for example. The memory 1011 stores in advance the numerical values calculated by the controller 1010, the internal resistance values of the lithium ion batteries 1002 in the initial state measured at the stage of the manufacturing process, and the like, and can be rewritten as appropriate. In addition, by storing the full charge capacity of the lithium ion battery 1002, it is possible to calculate, for example, the remaining capacity together with the controller 1010.

The temperature measuring unit 1015 measures the temperature using the temperature detecting element 1016, performs charge/discharge control during abnormal heat generation, and performs correction for calculating the remaining capacity.

The switching of the 1 st switch unit 41 and the 2 nd switch unit 42 may be performed based on the measurement result of the illuminance sensor (or the 2 nd illuminance sensor) as described above, may be performed by the operation of the observer 20, or may be performed in synchronization with the start of image formation or the end of image formation in the image forming apparatus.

As shown in fig. 11B, the voltage control circuit (regulator) 50 can be omitted as appropriate. As shown in fig. 12, the light control device 700 may be colored by providing

switching units

41A and 41B and 2

capacitors

33A and 33B, and applying a voltage higher than that of the 1 st electrode 712A to the 2 nd electrode 712B by discharging the capacitor 33A, and applying a voltage higher than that of the 2 nd electrode 712B to the 1 st electrode 712A by discharging the capacitor 33B, thereby decoloring the light control device 700. In these cases, the secondary battery control unit 32A may include a voltage control circuit that controls the value of the voltage applied to the 1 st electrode 712A and the 2 nd electrode 712B for controlling the light transmittance of the light modulation layer 716.

Fig. 14A shows a charging circuit 60 for charging the capacitor 33. The charging circuit 60 includes a comparator 61, a constant voltage IC with a current limiting function (hereinafter referred to as "constant voltage IC 62"), and a voltage control circuit (regulator) 50. Fig. 14B shows changes in potential at each site. In the charging circuit 60, the terminal voltage (V) of the constant voltage IC 62 is applied to the inverting terminal of the comparator 61 via the resistor R4 _ELDC ). By a reference voltage V _REF Resistors R1, R2, R3 to set the hysteresis voltage V ₁ 、V ₂ . Voltage at terminal (V) _ELDC ) Below voltage V ₂ At this time, the enable terminal EN of the constant voltage IC 62 transits to the "High, High" state, the constant voltage IC 62 turns ON (ON), and the limited current I flows _CHG The capacitor 33 is charged. Voltage at terminal (V) _ELDC ) To a voltage V ₁ (that is, the maximum voltage used by the capacitor 33), the enable terminal EN of the constant voltage IC 62 transitions to a "Low, Low" state, the constant voltage IC 62 turns OFF (OFF), and the charging ends. Such a charging circuit 60 may be disposed upstream of the capacitor 33 in the circuits shown in fig. 11A, 11B, and 12.

Fig. 15A and 15B illustrate light transmittance/

polarity control circuits

70A, 70B for controlling light transmittance and changing the polarity of the voltage applied to the 1 st electrode 712A and the 2 nd electrode 712B. The light transmittance/

polarity control circuits

70A and 70B control the voltages applied to the 1 st and 2

nd electrodes

712A and 712B according to the level of light transmittance, and control the polarities of the voltages applied to the 1 st and 2

nd electrodes

712A and 712B according to the coloring/decoloring instruction. The 2 nd switching unit 42 shown in fig. 11A and 11B is replaced with light transmittance/

polarity control circuits

70A and 70B.

The light transmittance/polarity control circuit 70A shown in fig. 15A is configured by 2

operational amplifiers

71A and 71B. To the non-inverting input parts of the operational amplifiers 71A, 71BV _DD Potential (V) with ground potential _DD X). The value of "x" is, for example, an integer of 2 or more. The potential V is input to the inverting input part of the operational amplifier 71B _IN . By potential V _IN The light transmittance of the light control device 700 is defined (set). The output unit of the operational amplifier 71B is connected to the 1 st electrode 712A of the light control device 700, and is also connected to the inverting input unit of the operational amplifier 71A. The output unit of the operational amplifier 71A is connected to the 2 nd electrode 712B of the light control device 700. The positive power supply of the 2

operational amplifiers

71A and 71B is connected to the voltage control circuit (regulator) 50, and the voltage control circuit 50 is connected to the capacitor 33. In addition, the negative power supplies of the 2

operational amplifiers

71A, 71B are grounded.

Alternatively, fig. 15B shows a light transmittance/polarity control circuit 70B, the light transmittance/polarity control circuit 70B includes 2 constant voltage circuits for outputting a + side voltage with reference to the ground, and the constant output voltage V with respect to one of the constant voltage circuits _out-1 And the output voltage V of the other constant voltage circuit is increased or decreased according to the output voltage control signal _out-2 Thereby, the light control device 700 performs control of coloring/decoloring (control of polarity of applied voltage) and control of light transmittance. In (V) _out-2 -V _out-1 )>In the case of 0, the light control device 700 is in the colored state at (V) _out-2 -V _out-1 )<In case 0, the light control device 700 is in the color erasing state. In addition, according to | V _out-2 -V _out-1 The value of | specifies the light transmission.

Fig. 16 shows a circuit diagram of another driving circuit of the light control device 700, and fig. 17 shows an explanation of the operation of the driving circuit shown in fig. 16. The DC voltage of the output of the D/a converter 81 changes according to the light transmittance setting signal of the light control device 700. When the DC voltage is high, the light transmittance of the light control device 700 decreases (coloring), and when the DC voltage is low, the light transmittance of the light control device 700 increases (decoloring). In addition, the edge portion of the DC voltage variation is extracted by the differentiating circuit 82. Further, after a few seconds have elapsed from the edge portion of the DC voltage change, the discharge current from the capacitor 33 starts to flow in the dimming layer 716. In addition, since the edge portion of the DC voltage change is bipolar, the polarity is unified in one direction by the absolute value circuit 83. In addition, a rectangular wave is generated by the comparator circuit 84, and is corrected to a waveform based on the ground by the level shifter circuit 85. Further, a delay for setting the period of the low level of the rectangular wave (the disabling period of the constant voltage IC 62) to the interval in which it is desired to avoid the discharge current from the capacitor 33 is generated with the single-multi delay IC 86.

In some cases, the light blocking rate of each region of the light control device may be controlled by dividing the 1 st electrode and/or the 2 nd electrode into a plurality of blocks and controlling the light blocking rate in each block. Alternatively, the light blocking rate in a plurality of regions of the light control device can be independently controlled by forming the 1 st electrode or the 2 nd electrode as a strip-shaped electrode or a mesh-shaped electrode, or by forming a strip-shaped auxiliary electrode or a mesh-shaped auxiliary electrode on the 1 st electrode or the 2 nd electrode. In some cases, the light control device may be constituted by a liquid crystal display device driven by, for example, an active matrix system or a simple matrix system, and the light shielding rate of the light control device may be controlled.

In the case where the control of the light shielding ratio in the light control device 700 is performed according to, for example, the simple matrix method, a schematic plan view of the light control device 700 is shown in fig. 2C,

the 1 st electrode 712A is composed of a plurality of strip-shaped 1 st electrode segments 712A' extending in the 1 st direction,

the 2 nd electrode 712B is composed of a plurality of strip-shaped 2 nd electrode segments 712B' extending in the 2 nd direction different from the 1 st direction,

the control of the light blocking rate of the portion of the light modulation device corresponding to the repetition region (the minimum unit region where the light blocking rate of the light modulation device changes) of the 1 st electrode segment 712A 'and the 2 nd electrode segment 712B' is performed according to the control of the voltage applied to the 1 st electrode segment 712A 'and the 2 nd electrode segment 712B'. The 1 st direction and the 2 nd direction are orthogonal, specifically, the 1 st direction extends in the lateral direction (X direction) and the 2 nd direction extends in the longitudinal direction (Y direction).

The dimming means 700 for achieving light transmission from 72% to 7% was evaluated. Make the light adjusting device 70The area of the region contributing to the dimming of 0 (hereinafter referred to as "dimming region") is, for example, 1120mm ² (═ 56mm by 20 mm). Further, the charge amount required for coloring/decoloring of such a light control device 700 can be measured to be 224 millicoulombs. Accordingly, the charge amount per unit area of the dimming region of the dimming device 700 is 0.2 millicoulomb/mm ² (＝224/1120)。

The area of the light modulation region is 1120mm ² In the light control device (1), it was experimentally confirmed that, when the current flowing between the 1 st electrode 712A and the 2 nd electrode 712B was not limited, the time required until the current flowing between the 1 st electrode 712A and the 2 nd electrode 712B became 20 milliamperes, for example, was 3.6 seconds after the coloring time and 1.8 seconds after the decoloring time. As is clear from the data of the current change with respect to time, 157 millicoulombs corresponding to 70% with respect to 224 millicoulombs of the charge amount after coloring were injected into the light control device during coloring, and 220 millicoulombs corresponding to 98% with respect to 224 millicoulombs of the charge amount after decoloring were injected into the light control device during decoloring. In addition, according to this, when the secondary battery 31 is subjected to a current limit of 20 ma at the time of coloring/decoloring, when the amount of charge necessary for coloring/decoloring is to be supplied from the capacitor 33 without impairing the operation speed, the amount of charge Q necessary for coloring/decoloring is required ₀ And the amount of change (Q) of the charge before and after the discharge of the capacitor 33 ₁ -Q ₂ ) Is Q ₀ X is 0.98 or more.

The charge amount is determined by the capacitance C of the capacitor 33 and the potential difference (V) before and after discharge ₁ -V ₂ ) And (6) determining. In practice, the voltage of the secondary battery 31 for charging the capacitor 33 is set to a commercial rated voltage of 3.7 volts. This voltage and the voltage V at the start of discharge of the capacitor 33 ₁ And (4) the equivalent. Voltage V if a current immediately after the light-adjusting layer 716 is sufficiently charged, i.e., below the limiting current, begins to flow ₂ When the voltage is set to 1.5 volts, the voltage control circuit has a simpler circuit configuration. Further, in this case, the voltage supply unit is configured to supply a charge of 220 mCoulombs corresponding to 98% in 224 mCoulombs relative to the decoloring-completed charge amount at a potential difference of 2.2 volts (3.7 volts to 1.5 volts)The capacitance C required for the capacitor 33 is set to

C＝Q/ΔV＝220[mC]/2.2[V]＝100[mF]

The above. Actually, a discharge current of the same level as that of the secondary battery 31 in the case where there is no current limitation can be obtained from the capacitor 33, and the average current in the discharge of the capacitor 33 at the time of decoloring is about 124 millicoulombs/second (124 milliamperes).

Discharge time T of capacitor 33 _Discahrge In general, when the output of the capacitor 33 is P, there is a case where P is the output

T _Discahrge ＝(1/2)×C×(V ₁ ² -V ₂ ² )/P

Such a relationship (see technical information of ELMA company, https:// www.elna.co.jp/modulator/double _ layer/pdf/calculation. pdf). Here, the output P (output current) × (output voltage), the output current is approximated by an average current during discharge of 124 millicoulombs/sec (124 milliamperes), and the output voltage is { (V) } ₁ +V ₂ ) 2.6 volts is approximate output voltage

T _Discahrge ＝(1/2)×100[mC/V]×(3.7 ² -1.5 ² )[V ² ]

/(124X 2.6) [ mC.V/sec ]

Is approximately equal to 1.8 seconds,

it is understood that the operation speed equivalent to the discharge by the secondary battery in the case where there is no current limitation can be obtained by driving the light control device 700 by the capacitor 33. Further, although the discharge voltage of the capacitor 33 decreases with the discharge, a constant voltage is applied to the light control device 700 by the voltage control circuit.

In the light control device, the actual operation speed of the light control device and the amount of charge required for the capacitor 33 are different depending on the area of the light control region, the range of required light transmittance, the limit current, the rated voltage of the secondary battery 31, and the voltage applied between the electrodes of the light control device. The example described above is in the size of sunglasses (area contributing to the light modulation: 1120 mm) ² ) In the light modulation device of (3), the transmittance range of the light transmittance is 72% to 8%Coloring/decoloring and voltage V between electrodes ₂ An example of this is 1.5 volts. It is assumed that the current discharged by the capacitor 33 in this case is about 300 ma at maximum.

In addition, the charge amount per unit area is 0.2 millicoulombs/mm ² The value of (d) is the amount of charge required for coloring and decoloring the light control device, which is experimentally confirmed, but actually, when the light transmittance range is to be widened, a larger amount of charge is required. Since the charge amount of the capacitor 33 also varies depending on the voltage, the capacitance C [ F/mm ] per unit area is a capacitance capable of supplying a necessary charge amount even at a low voltage (0.2 volt) ² ]Can be estimated as

C＝Q[mC/mm ² ]/V[V]

＝0.2×10 ^-3 /0.2

＝0.001[F/mm ² ]，

Considering a narrower light transmittance range and voltage, the voltage is set to

C/A>1×10 ^-6 [F/mm ² ]。

The operation time of the capacitor 33 corresponding to the limit current of 20 ma (3.6 seconds at the time of coloring and 1.8 seconds at the time of decoloring) was also experimentally confirmed. However, when the area of the light modulation region in the light modulation device is increased, the operation time is increased (slowed) regardless of the operation circuit. Therefore, the relationship between the area of the light control region and the operation time may be determined in consideration of the practical value and the actual operation speed.

As described above, since the display device of example 1 includes the light control device, it is possible to provide a high contrast to the virtual image observed by the observer. Further, the coloring/decoloring of the light control device can be promptly performed by applying the voltage to the 1 st electrode and the 2 nd electrode by the discharge of the capacitor, and a small-sized secondary battery can also be used. Further, since the capacitor is charged by the secondary battery, the entire configuration of the control unit can be simplified, and the display device can be reduced in weight and size. The control unit performs a predetermined time (T) from the start of coloring or decoloring of the light control device ₀ ) After based on twoSince the voltage is applied to the 1 st electrode and the 2 nd electrode of the secondary battery, the light transmittance value of the light control device can be stabilized.

Further, as described above, in the secondary battery control section, the controller performs control such as to suppress the flow of a large current from the secondary battery control section. Therefore, in the case of using such a secondary battery control unit, it is difficult to flow a large current between the 1 st electrode and the 2 nd electrode in order to rapidly change the light transmittance of the light modulation layer. However, in embodiment 1, the light control device includes a capacitor, and the coloring and decoloring of the light control device can be performed promptly by applying a voltage to the 1 st electrode and the 2 nd electrode based on the discharge of the capacitor. Further, if voltage application to the 1 st electrode and the 2 nd electrode by the secondary battery is performed after a predetermined time has elapsed from the start of coloring of the light adjustment layer, stabilization of the colored state of the light adjustment layer can be achieved.

Example 2

Embodiment 2 is a modification of embodiment 1, and relates to the optical device of the structure 1-a and the image forming apparatus of the structure 2. Fig. 18 shows a conceptual diagram of an image display apparatus 200 in a display apparatus (head mounted display) of embodiment 2, and in embodiment 2, an image forming apparatus 211(211A, 211B) is constituted by an image forming apparatus of the 2 nd configuration. That is, the scanning unit 253 is provided with the light source 251 and scans the parallel light emitted from the light source 251.

More specifically, image forming apparatus 211 includes:

a light source 251;

a collimating optical system 252 for collimating the light emitted from the light source 251;

a scanning unit 253 that scans the parallel light emitted from the collimating optical system 252; and

the relay optical system 254 relays and emits the parallel light scanned by the scanning unit 253.

The image forming apparatus 211 is entirely housed in a housing 213 (indicated by a one-dot chain line in fig. 18), and an opening (not shown) is provided in the housing 213, and light is emitted from the relay optical system 254 through the opening. Each housing 213 is detachably mounted to the temple portion 13 via a mounting member 19.

The light source 251 is constituted by a light emitting element that emits white light. The light emitted from the light source 251 enters the collimating optical system 252 having a positive optical power as a whole, and is emitted as parallel light. The parallel light is reflected by the total reflection mirror 256, and a virtual pixel (the number of pixels may be the same as that in example 1, for example) that is two-dimensionally imaged is generated by performing horizontal scanning and vertical scanning by the scanning unit 253 that is configured by an MEMS capable of two-dimensionally scanning the incident parallel light by rotating the micromirror in the two-dimensional direction. The light from the dummy pixel passes through a relay optical system (parallel light emitting optical system) 254 formed of a known relay optical system, and is incident on the optical device 120 as a parallel light beam.

The optical device 120 into which the light flux that is parallel light by the relay optical system 254 enters and guides and emits the light flux has the same configuration and structure as those of the optical device described in embodiment 1, and therefore, detailed description thereof is omitted. The display device of example 2 has substantially the same configuration and structure as those of the display device of example 1, except for the points that the image forming apparatus 211 is different from the above, and therefore, detailed description thereof is omitted.

Example 3

Example 3 is also a modification of example 1, and relates to the optical device of the 1 st configuration and the image forming apparatus of the 1 st configuration. Fig. 19 shows a conceptual diagram of an image display device 300 in the display device (head mounted display) of embodiment 3. Fig. 20 is a schematic cross-sectional view showing a part of a reflection type volume hologram diffraction grating in an enlarged manner. In example 3, the image forming apparatus 111 'is constituted by an organic EL display device 150' as in example 1. The image forming apparatus 111 'is constituted by an organic EL display device 150' as in example 1. Further, the image forming apparatus 111 in embodiment 1 shown in fig. 4 may be used as the image forming apparatus. The basic structure and structure of the optical device 320 are the same as those of the optical device 120 of embodiment 1, except that the structures and structures of the 1 st deflection unit and the 2 nd deflection unit are different.

In embodiment 3, the 1 st deflecting unit and the 2 nd deflecting unit are disposed on the surface of the light guide plate 321 (specifically, the 2 nd surface 323 of the light guide plate 321). The 1 st deflecting means diffracts light incident on the light guide plate 321, and the 2 nd deflecting means diffracts light propagating through total reflection inside the light guide plate 321. Here, the 1 st deflection unit and the 2 nd deflection unit are configured by diffraction grating elements, specifically, reflection type diffraction grating elements, more specifically, reflection type volume hologram diffraction gratings. In the following description, for convenience, the 1 st deflection unit formed of a reflection type volume hologram diffraction grating is referred to as "1 st diffraction grating member 330", and for convenience, the 2 nd deflection unit formed of a reflection type volume hologram diffraction grating is referred to as "2 nd diffraction grating member 340".

In example 3 or example 4 to be described later, the 1 st diffraction grating member 330 and the 2 nd diffraction grating member 340 have a structure in which 1 diffraction grating layer is laminated. Interference fringes corresponding to 1 wavelength band (or wavelength) are formed in each diffraction grating layer made of a photopolymer material, and the diffraction grating layer is manufactured by a conventional method. The pitch of the interference fringes formed in the diffraction grating layer (diffraction grating element, diffraction grating member) is constant, and the interference fringes are linear and extend in the Y direction. The axes of the 1 st diffraction grating member 330 and the 2 nd diffraction grating member 340 extend in the X direction, and the normal lines extend in the Z direction.

Fig. 20 is a partially enlarged cross-sectional view of a reflection type volume hologram diffraction grating. In the reflection type volume hologram diffraction grating, a grating having an inclination angle (tilt angle)

The interference fringes of (1). Here, the angle of inclination

Refers to the angle formed by the surface of the reflection type volume hologram diffraction grating and the interference fringes. Interference fringe reflection type volume hologramThe interior of the diffraction grating is formed continuously to the surface. The interference fringes satisfy the bragg condition. Here, the bragg condition is a condition satisfying the following formula (a). In formula (a), m represents a positive integer, λ represents a wavelength, d represents a pitch of a grating surface (a space in a normal direction of a virtual plane including interference fringes), and Θ represents a complementary angle of an angle incident to the interference fringes. When light enters the diffraction grating member at an incident angle ψ, the tilt angle Θ

The incidence angle ψ has a relationship as shown in formula (B).

m·λ＝2·d·sin(Θ) (A)

The 1 st diffraction grating member 330 is disposed (bonded) to the 2 nd surface 323 of the light guide plate 321 as described above, and diffracts (specifically, diffracts and reflects) the parallel light incident on the light guide plate 321 from the 1 st surface 322 so that the parallel light incident on the light guide plate 321 is totally reflected inside the light guide plate 321. The 2 nd diffraction grating member 340 is disposed (bonded) to the 2 nd surface 323 of the light guide plate 321 as described above, diffracts (specifically, multiply diffractively reflects) the parallel light propagating by total reflection in the light guide plate 321, and emits the parallel light from the 1 st surface 322 from the light guide plate 321 while remaining parallel.

In the light guide plate 321, the parallel light propagates inside by total reflection and is then emitted. At this time, the light guide plate 321 is thin and the optical path running inside the light guide plate 321 is long, so the number of total reflections reaching the 2 nd diffraction grating member 340 differs according to each viewing angle. More specifically, of the parallel light beams incident on the light guide plate 321, the number of reflections of the parallel light beams incident at an angle in a direction approaching the 2 nd diffraction grating member 340 is smaller than the number of reflections of the parallel light beams incident on the light guide plate 321 at an angle in a direction away from the 2 nd diffraction grating member 340. This is because the angle formed by the light propagating inside the light guide plate 321 and the normal line of the light guide plate 321 when the light is collided with the inner surface of the light guide plate 321 is smaller in the parallel light incident on the light guide plate 321 at an angle close to the direction of the 2 nd diffraction grating member 340 diffracted by the 1 st diffraction grating member 330 than in the parallel light incident on the light guide plate 321 at an angle in the direction opposite thereto. The shape of the interference fringes formed inside the 2 nd diffraction grating member 340 and the shape of the interference fringes formed inside the 1 st diffraction grating member 330 are symmetrical with respect to a virtual plane perpendicular to the axis of the light guide plate 321. The surfaces of the 1 st diffraction grating member 330 and the 2 nd diffraction grating member 340 not facing the light guide plate 321 may be covered with a transparent resin plate or a transparent resin film to prevent the 1 st diffraction grating member 330 and the 2 nd diffraction grating member 340 from being damaged. In addition, a transparent protective film may be attached to the 1 st surface 322 to protect the light guide plate 321.

The light guide plate 321 in embodiment 4 to be described later basically has the same structure and structure as those of the light guide plate 321 described above.

The display device of example 3 has substantially the same configuration and structure as those of the display device of example 1 except for the point that the optical device 320 is different as described above, and therefore, detailed description thereof is omitted.

Example 4

Example 4 is also a modification of example 1, and relates to the optical device of the 1 st-B structure and the image forming apparatus of the 2 nd structure. Fig. 21 shows a conceptual diagram of an image display apparatus in the display apparatus (head mounted display) of embodiment 4. The light source 251, the collimating optical system 252, the scanning unit 253, the parallel light emitting optical system (the relay optical system 254), and the like in the image display device 400 of embodiment 4 have the same structure and structure as those of embodiment 2 (the image forming apparatus of the 2 nd structure). The optical device 320 in embodiment 4 has the same structure and structure as the optical device 320 in embodiment 3. The display device of example 4 has substantially the same configuration and structure as those of the display device of example 1 except for the above difference, and therefore, detailed description thereof is omitted.

Example 5

Embodiment 5 is also a modification of the image display device of embodiment 1, and relates to the optical device of the 2 nd structure and the image forming apparatus of the 2 nd structure. Fig. 22 shows a schematic view of the display device of example 5 viewed from above.

In example 5, the optical device 520 constituting the image display device 500 is constituted by the half mirrors 530A and 530B into which the light emitted from the

light sources

251A and 251B is incident and which emit the light toward the pupil 21 of the observer 20. In example 5, light emitted from the light source 251(251A, 251B) disposed in the housing 213 propagates through the inside of an optical fiber (not shown), and enters the scanning unit 253(253A, 253B) of the portion of the mirror ring 11 'attached near the nose pad portion 10', for example, and light scanned by the scanning unit 253 enters the semi-transmissive mirrors 530A, 530B. Alternatively, light emitted from the

light sources

251A and 251B disposed in the housing 213 propagates through an optical fiber (not shown), and enters, for example, the scanning units 253(253A and 253B) attached above the portions of the mirror rings 11' corresponding to the eyes, respectively, and light scanned by the scanning units 253 enters the

semi-transmissive mirrors

530A and 530B. Alternatively, light emitted from

light sources

251A and 251B disposed in housing 213 is incident on scanning unit 253(253A and 253B) disposed in housing 213, and light scanned by scanning unit 253 is directly incident on half-

transmissive mirrors

530A and 530B. Then, the light reflected by the half-

transmissive mirrors

530A and 530B enters the pupil 21 of the observer 20. The image forming apparatus 211 described in embodiment 2 can be substantially used as the image forming apparatus. The display device of example 5 has substantially the same configuration and structure as the display device of example 1 except for the above differences, and therefore, detailed description thereof is omitted.

Example 6

Example 6 is a modification of example 1. Fig. 23A shows a schematic view of the display device of embodiment 6 as viewed from above. In addition, fig. 23B shows a schematic diagram of a circuit that controls the illuminance sensor.

The display device of embodiment 6 further includes an illuminance sensor (ambient illuminance measurement sensor) 901 that measures the illuminance of the environment in which the display device is placed, and the light blocking ratio of the light control device 700 is controlled based on the measurement result of the illuminance sensor (ambient illuminance measurement sensor) 901. The brightness of the images formed by the

image forming apparatuses

111 and 211 is controlled based on the measurement result of the illuminance sensor (ambient illuminance measurement sensor) 901, either collectively or independently. The ambient illuminance measurement sensor 901 having a known configuration and structure may be disposed, for example, at an outer end of the light control device 700. The ambient illuminance measurement sensor 901 is connected to the control device 18 via a connector and wiring not shown. The control device 18 includes a circuit for controlling the ambient illuminance measurement sensor 901. The circuit for controlling the ambient illuminance measurement sensor 901 includes: an illuminance calculation circuit that receives a measurement value from the ambient illuminance measurement sensor 901 and calculates illuminance; a comparison operation circuit for comparing the value of the illuminance obtained by the illuminance operation circuit with a standard value; the ambient illuminance measurement sensor control circuit may be a known circuit that controls the light control device 700 and/or the

image forming devices

111 and 211 based on the value obtained by the comparison and calculation circuit. The control of light control device 700 controls the light shielding rate of light control device 700, while the control of

image forming devices

111 and 211 controls the brightness of images formed by

image forming devices

111 and 211. The control of the light shielding ratio in light control device 700 and the control of the brightness of the image in

image forming devices

111 and 211 may be performed independently of each other or may be performed in association with each other.

For example, when the measurement result of the illuminance sensor (ambient illuminance measurement sensor) 901 becomes equal to or greater than a predetermined value (1 st illuminance measurement value), the light blocking ratio of the light control device 700 is set to be equal to or greater than a predetermined value (1 st light blocking ratio). On the other hand, when the measurement result of the illuminance sensor (ambient illuminance measurement sensor) 901 becomes equal to or less than the predetermined value (2 nd illuminance measurement value), the light blocking ratio of the light control device 700 is set to be equal to or less than the predetermined value (2 nd light blocking ratio). Here, 10 lux can be exemplified as the 1 st illuminance measurement value, any value of 99% to 70% can be exemplified as the 1 st light shielding rate, 0.01 lux can be exemplified as the 2 nd illuminance measurement value, and any value of 49% to 1% can be exemplified as the 2 nd light shielding rate.

The illuminance sensor (ambient illuminance measurement sensor) 901 in example 6 can be applied to the display devices described in examples 2 to 5. When the display device includes an imaging device, an illuminance sensor (ambient illuminance measurement sensor) 901 may be formed by a light receiving element for exposure measurement provided in the imaging device.

In the display device of example 6 or example 7 described below, the light blocking ratio of the light control device is controlled based on the measurement result of the illuminance sensor (ambient illuminance measurement sensor), the luminance of the image formed by the image forming device is controlled based on the measurement result of the illuminance sensor (ambient illuminance measurement sensor), the light blocking ratio of the light control device is controlled based on the measurement result of the 2 nd illuminance sensor (transmitted light illuminance measurement sensor), and the luminance of the image formed by the image forming device is controlled based on the measurement result of the 2 nd illuminance sensor (transmitted light illuminance measurement sensor), so that not only a high contrast can be provided to the virtual image observed by the observer, but also the observation state of the virtual image can be optimized based on the illuminance of the surrounding environment in which the display device is placed.

Example 7

Example 7 is also a modification of example 1. Fig. 24A shows a schematic view of the display device of embodiment 7 as viewed from above. In addition, fig. 24B shows a schematic diagram of a circuit that controls the 2 nd illuminance sensor.

The display device of example 7 further includes a 2 nd illuminance sensor (transmitted light illuminance measurement sensor) 902 that measures illuminance of light transmitted through the light control device from the external environment, that is, measures whether or not ambient light enters after being adjusted to a desired illuminance through the light control device, and controls the light blocking ratio of the light control device 700 based on the measurement result of the 2 nd illuminance sensor (transmitted light illuminance measurement sensor) 902. In addition, the brightness of the images formed by the

image forming apparatuses

111 and 211 is controlled based on the measurement result of the 2 nd illuminance sensor (transmitted light illuminance measurement sensor) 902, either collectively or independently. The transmitted light illuminance measurement sensor 902 having a known configuration and structure is disposed closer to the observer side than the

optical devices

120, 320, and 520. Specifically, the transmitted light illuminance measurement sensor 902 may be disposed on the inner surface of the

casing

113 or 213, for example. The transmitted light illuminance measurement sensor 902 is connected to the control device 18 via a connector and a wiring, not shown. The control device 18 includes a circuit for controlling the transmitted light illuminance measurement sensor 902. The circuit for controlling the transmitted light illuminance measurement sensor 902 includes: an illuminance calculation circuit that receives the measurement value from the transmitted light illuminance measurement sensor 902 and obtains illuminance; a comparison operation circuit for comparing the value of the illuminance obtained by the illuminance operation circuit with a standard value; the transmitted light illuminance measurement sensor control circuit may be a known circuit for controlling the light control device 700 and/or the

image forming devices

111 and 211 based on the value obtained by the comparison and calculation circuit. The light blocking rate of the light control device 700 is controlled in the control of the light control device 700, while the brightness of the image formed by the

image forming devices

111 and 211 is controlled in the control of the

image forming devices

111 and 211. The control of the light shielding rate in light control device 700 and the control of the brightness of the image in

image forming devices

111 and 211 may be performed independently or in association with each other. In addition, when the measurement result of the transmitted light illuminance measurement sensor 902 cannot be controlled to a desired illuminance in consideration of the illuminance of the ambient illuminance measurement sensor 901, that is, when the measurement result of the transmitted light illuminance measurement sensor 902 does not become the desired illuminance, or when finer illuminance adjustment is desired, the light blocking ratio of the light control device may be adjusted while monitoring the value of the transmitted light illuminance measurement sensor 902. At least 2 of the 2 nd illuminance sensors (transmitted light illuminance measuring sensors) may be arranged to measure the illuminance based on light passing through a portion with a high light blocking ratio and to measure the illuminance based on light passing through a portion with a low light blocking ratio.

The 2 nd illuminance sensor (transmitted light illuminance measurement sensor) 902 in example 7 can be applied to the display devices described in examples 2 to 5. Alternatively, the 2 nd illuminance sensor (transmitted light illuminance measuring sensor) 902 in example 7 and the illuminance sensor (ambient illuminance measuring sensor) 901 in example 6 may be combined, and in this case, the control of the light blocking ratio in the light control device 700 and the control of the brightness of the image in the

image forming devices

111 and 211 may be performed independently by performing various tests or may be performed in association with each other. By adjusting the voltages applied to the 1 st electrode and the 2 nd electrode in each of the right-eye light control device and the left-eye light control device, the light blocking ratio in the right-eye light control device and the light blocking ratio in the left-eye light control device can be equalized. The potential difference between the 1 st electrode and the 2 nd electrode may be controlled, or the voltage applied to the 1 st electrode and the voltage applied to the 2 nd electrode may be independently controlled. The light blocking ratio in the right-eye light control device and the light blocking ratio in the left-eye light control device can be controlled based on the measurement result of the 2 nd illuminance sensor (transmitted light illuminance measurement sensor) 902, for example, or can be manually controlled and adjusted by the observer 20 by observing the brightness of light passing through the right-eye light control device and the optical device and the brightness of light passing through the left-eye light control device and the optical device by the observer 20 and operating a switch, a button, a dial, a slider, a knob, or the like.

Example 8

Example 8 is a modification of example 1 to example 7. In the light control device according to example 8, a moisture holding member is disposed at least between the 2 nd electrode and the 2 nd substrate.

As shown in the schematic cross-sectional view of fig. 25A, a light control device 700' according to embodiment 8 includes:

the 1 st substrate 711A;

a 2 nd substrate 711B arranged to face the 1 st substrate 711A and on which external light is incident; and

a light modulation layer 716 provided between the 1 st substrate 711A and the 2 nd substrate 711B,

a1 st electrode 712A is disposed between the dimming layer 716 and the 1 st substrate 711A,

a 2 nd electrode 712B is disposed between the dimming layer 716 and the 2 nd substrate 711B,

the light control layer 716 has a laminated structure of a reduction coloring layer 713, an electrolyte layer 714, and an oxidation coloring layer 715.

Further, a moisture holding member 721 is disposed at least between the 2 nd electrode 712B and the 2 nd substrate 711B. The end surface of the water holding member 721 is exposed to the outside. At least a part of the end (side surface) of the light control device 700' is constituted by a sealing member 723 and a water holding member 721 from the 1 st substrate side. That is, at least a part of the end of the light control device 700' is configured by a laminated structure of the sealing member 723 and the moisture holding member extension 722 extending from the moisture holding member 721 from the 1 st substrate side. The sealing member 723 is provided at an edge portion of the 1 st substrate 711A, for example.

The 2 nd electrode 712B is formed to extend from the light modulation layer 716 to the 1 st substrate 711A and to be separated from the 1 st electrode 712A, and the moisture holding member 721 covers at least the 2 nd electrode 712B and the light modulation layer 716. That is, the 1 st electrode 712A is formed on the 1 st substrate 711A, the light modulation layer 716 is formed on the 1 st electrode 712A, the 2 nd electrode 712B is formed at least on the light modulation layer 716, and the moisture holding member 721 faces the 2 nd substrate 711B while covering at least the 2 nd electrode 712B. A moisture holding member extending portion 722 extending from the moisture holding member 721 is disposed between the sealing member 723 and the 2 nd substrate 711B. A part of the sealing member 723 is formed of an auxiliary electrode (not shown), and the auxiliary electrode is formed of copper (Cu). The remaining portion of the sealing member 723 is made of a resin, specifically, an acrylic adhesive. The auxiliary electrode includes a1 st auxiliary electrode (not shown) formed on the 1 st electrode 712A and a 2 nd auxiliary electrode (not shown) formed on the 2 nd electrode 712B separately from the 1 st auxiliary electrode. The sealing member 723 and the moisture holding member extension 722 form a sidewall of the light control device 700'. The sealing member 723 is provided without a gap.

The resin constituting the water retaining member 721 and the water retaining member extension 722, which can also be referred to as a proton supplying member, a transparent adhesive member capable of retaining water, or a transparent sealing member capable of retaining water, may be appropriately selected from acrylic resins, silicone resins, or urethane resins, and in example 8, specifically, is constituted by acrylic resins.

By the Young's modulus of 1X 10 ⁶ The moisture holding member 721 and the moisture holding member extension 722 are made of a material having Pa or less, and can absorb various steps generated inside the light control device and reduce the moisture holding member 7 in the central portion of the light control device21, and the thickness of the moisture holding member extension 722. That is, the distance between the 1 st substrate 711A and the 2 nd substrate 711B can be made uniform as a whole. As a result, the occurrence of deterioration in visibility can be prevented. Specifically, it is possible to suppress the occurrence of distortion or deviation in an image of the outside world when the outside world is observed through the dimming device 700'.

The 1 st electrode 712A and the 2 nd electrode 712B made of ITO or IZO are not patterned, and are what are called beta electrodes. A connector (not shown) is attached to a part of the auxiliary electrode of the light control device 700 ', and the 1 st electrode 712A and the 2 nd electrode 712B are electrically connected to the control unit 30 for controlling the light blocking ratio of the light control device 700'.

When moisture disappears inside the electrochromic element, a phenomenon occurs in which no color change occurs in the electrochromic element. However, in the light control device of example 8, since the entry and exit of moisture are generated via the end face of the moisture holding member extension portion (the side wall of the light control device), it is possible to avoid a problem that the reliability of the light control device, the image display device, or the display device is lowered. Further, if the auxiliary electrode is provided, an appropriate voltage can be easily applied to the 1 st electrode and the 2 nd electrode, and the voltage drop in the 1 st electrode or the 2 nd electrode can be suppressed, and as a result, the occurrence of unevenness in coloring of the light control device can be reduced.

Example 9

Example 9 is also a modification of examples 1 to 7. The light control device of example 9 is configured by one type of optical shutter based on a plating method (electrodeposition method or electric field deposition method) to which a plating/electrolysis phenomenon generated by a reversible redox reaction of a metal (e.g., silver particles) is applied. Fig. 25B shows a schematic cross-sectional view of a dimming device of embodiment 9.

In such a light control device, when the light control layer is formed of an electrolyte layer containing metal ions, it is desirable that the metal ions be formed of silver ions and the electrolyte contain at least 1 salt (referred to as "supporting electrolyte salt") selected from the group consisting of LiX, NaX, and KX (where X is a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom).

Further, the following is preferable: the coloring and decoloring of the light control device (specifically, the electrodeposition type light control device) are caused by the precipitation of the metal (for example, silver) on the 2 nd electrode and the dissolution of the metal (for example, silver) into the electrolyte based on the voltage application to the 1 st electrode and the 2 nd electrode. If the metal ions are silver ions and the 2 nd electrode is made of silver, that is, if the metal material and the metal ions constituting the 2 nd electrode are made of the same metal, an electrochemically stable electrode reaction can be achieved.

The electrolyte contains metal ions as a material that is colored (developed) by electrochemical reduction/oxidation and precipitation/dissolution associated therewith. Further, coloring (color development) and decoloring are performed by electrochemical precipitation/dissolution reaction of the metal ions, and the light shielding rate of the light control device is changed. In other words, the operation of the light control device in such a display device can be referred to as an operation in which precipitation of a metal and elution reaction of the precipitated metal due to so-called electrolytic plating are reversibly caused. As the metal ions capable of coloring (color development) and decoloring by electrochemical deposition/dissolution, there are no particular limitations on the metal ions, and in addition to the above silver (Ag), there can be exemplified ions of bismuth (Bi), copper (Cu), sodium (Na), lithium (Li), iron (Fe), chromium (Cr), nickel (Ni), and cadmium (Cd), and combinations of these ions, and among them, silver (Ag) and bismuth (Bi) are particularly preferable metal ions. Silver and bismuth can facilitate reversible reaction and have high discoloration degree when precipitated.

Further, metal ions are contained in the electrolyte, and specifically, a substance containing metal ions is dissolved in the electrolyte. More specifically, the substance containing metal ions includes at least 1 kind of silver halide such as AgF, AgCl, AgBr, and AgI, preferably AgI or AgBr, and the substance containing metal ions dissolves in the electrolyte. The concentration of the silver halide can be, for example, 0.03 mol/l to 2.0 mol/l.

An electrolyte containing metal ions is sealed between the 1 st substrate and the 2 nd substrate, and the electrolyte may be an electrolytic solution or a polymer electrolyte. As the electrolytic solution, an electrolytic solution containing a metal salt or an alkyl quaternary ammonium salt in a solvent can be used. Specifically, as the electrolyte, water, ethanol, isopropanol, 2-ethoxyethanol, 2-methoxyethanol, propylene carbonate, dimethyl carbonate, ethylene carbonate, γ -butyrolactone, acetonitrile, sulfolane, dimethoxyethane, Dimethylformamide (DMF), Diethylformamide (DEF), Dimethylsulfoxide (DMSO), N-Dimethylacetamide (DMAA), N-Methylpropionamide (MPA), N-Methylpyrrolidone (MP), Dioxolane (DOL), Ethyl Acetate (EA), Tetrahydrofuran (THF), methyltetrahydrofuran (MeTHF), or a mixture thereof can be used. Examples of the matrix (base) polymer used in the polymer electrolyte include a polymer material having repeating units of alkylene oxide, alkylene imine, or alkylene sulfide in a main skeleton unit, a side chain unit, or a main skeleton unit and a side chain unit, a copolymer containing a plurality of these different units, a polymethyl methacrylate derivative, polyvinylidene fluoride, polyvinylidene chloride, polyacrylonitrile, a polycarbonate derivative, or a mixture thereof. In the case where the electrolyte is composed of a polymer electrolyte, the electrolyte may be a single layer, or may have a laminated structure in which a plurality of polymer electrolytes are laminated.

A matrix polymer that swells by adding water or an organic solvent can also be used. When a response speed or the like is particularly required, the metal ions contained in the electrolyte can be more easily moved by adding water or an organic solvent to the matrix polymer.

In addition, depending on the characteristics of the matrix polymer and the desired electrochemical reaction, it is preferable to add water, ethanol, isopropanol, or a mixture thereof when hydrophilicity is required, and it is preferable to add propylene carbonate, dimethyl carbonate, ethylene carbonate, γ -butyrolactone, acetonitrile, sulfolane, dimethoxyethane, ethanol, isopropanol, dimethylformamide, dimethyl sulfoxide, dimethylacetamide, N-methylpyrrolidone, or a mixture thereof when hydrophobicity is required.

As described above, the coloring and decoloring of the light control device (specifically, the electrodeposition type light control device) occurs by the precipitation of the metal on the 2 nd electrode and the dissolution of the metal into the electrolyte based on the voltage application to the 1 st electrode and the 2 nd electrode. Here, in general, unevenness is generated on the surface of the layer (metal layer) made of the metal deposited on the 2 nd electrode in contact with the electrolyte, and the surface of the metal layer in contact with the 2 nd electrode is seen as a black color. Therefore, in the case of use as a dimming device, it is desirable that the face of the metal layer in contact with the electrolyte face the observer side. In other words, the 1 st substrate is preferably disposed closer to the viewer than the 2 nd substrate.

Preferably, the 2 nd electrode is not patterned in the effective region of the light control device. That is, it is preferable that a portion of the 2 nd electrode occupying the effective region of the light control device is formed of a transparent electrode layer (so-called beta transparent electrode layer) which is not patterned. Specifically, it is preferable that the size of the projection image of the 2 nd electrode, which is not patterned, is the same as or larger than the projection image of the 2 nd deflection unit. The portion of the 2 nd electrode that is drawn to the outside, etc. may also be patterned.

As described above, by adding a salt (supporting electrolyte salt) containing an ion species different from the metal ion species to be precipitated/dissolved to the electrolyte, the electrochemical precipitation/dissolution reaction can be performed more efficiently and stably. Examples of such a supporting electrolyte salt include the lithium salt, potassium salt, sodium salt, and tetraalkylammonium salt. Specific examples of the lithium salt include LiCl, LiBr, LiI, and LiBF ₄ 、LiClO ₄ 、LiPF ₆ 、LiCF ₃ SO ₃ And the like. Specific examples of the potassium salt include KCl, KI, KBr and the like. Specific examples of the sodium salt include NaCl, NaI, and NaBr. Specific examples of the tetraalkylammonium salt include tetraethylammonium borofluoride, tetraethylammonium perchlorate, tetrabutylammonium borofluoride, tetrabutylammonium perchlorate, tetrabutylammonium halide, and the like. The alkyl chain length of the quaternary ammonium salt may be different from each other. Supporting electrolyte salt to containThe concentration of the metal ion substance may be, for example, about 1/2 to 5 times. In addition, inorganic particles may be mixed as a colorant in an electrolyte composed of a polymer electrolyte.

In addition, in the electrolyte, at least 1 kind of additives such as a growth inhibitor, a stress inhibitor, a brightener, a complexing agent, and a reducing agent may be added in order to reversibly and efficiently perform an electrochemical reaction, particularly deposition/dissolution of a metal. Such an additive is preferably an organic compound having a group having an oxygen atom or a sulfur atom, and for example, at least 1 selected from the group consisting of thiourea, 1-allyl-2-thiourea, mercaptobenzimidazole, coumarin, phthalic acid, succinic acid, salicylic acid, glycolic acid, dimethylamine borane (DMAB), trimethylamine borane (TMAB), tartaric acid, oxalic acid, and D-glucose-1, 5-lactone is preferably added. In particular, addition of mercaptobenzimidazole based on mercaptoalkylimidazole (see the following structural formula) is preferable because reversibility is improved and effects of excellent long-term storage stability and high-temperature storage stability can be obtained.

Wherein R1, R2 and R3 are each a hydrogen atom or a group consisting of C _n H _2n+1 (wherein n is an integer of 1 or more).

In addition, when an electrochemical reaction occurs, side reactions other than the predetermined reaction may occur. For example, in the case where a salt containing a halide is contained in the electrolyte, they are oxidized from an ionic state by a reaction shown below according to a potential. In addition, color development other than the desired color development occurs concomitantly.

I ₂ +2e ^- Either ^- (0.536V)

Br ₂ +2e ^- Either → or ← 2Br ^- (1.065V)

Cl ₂ +2e ^- Either → or ← 2Cl ^- (1.360V)

Therefore, in order to eliminate the occurrence of such unwanted color development, it is necessary to suppress the above-mentioned side reaction and reduce the oxidized halogen compound. In this case, a general reducing agent may be used as the reducing agent, and the reducing agent may be added to the electrolyte as an additive. As such a reducing agent, for example, an ascorbic acid compound, a trialkylalkanolamine represented by the following formula, and the like are preferable.

In particular, triethanolamine represented by the following formula, which is a type of trialkylamine, is preferably added to the electrolyte because of the excellent effects obtained even in long-term storage stability and high-temperature storage stability.

In addition, when a reduction reaction occurs due to a side reaction other than the predetermined reaction, an oxidizing agent is added. Therefore, in the case of metal deposition, it is preferable to add a reducing agent or an oxidizing agent to the electrolyte for suppressing a side reaction mainly caused by an anion species, which may occur in any of the 1 st electrode and the 2 nd electrode.

In the light control device of embodiment 9, the distance between the 1 st electrode and the 2 nd electrode is preferably 20 μm to 200 μm. It is preferable that the shorter the distance between the 1 st electrode and the 2 nd electrode, the lower the resistance between the electrodes, and the shorter the coloring/decoloring time and the lower the power consumption are achieved. However, when the distance between the 1 st electrode and the 2 nd electrode is less than 20 μm, the mechanical strength is reduced, and pinholes and cracks may occur. In addition, when the distance between the 1 st electrode and the 2 nd electrode is too short, the electric field concentration is shifted, so that color unevenness occurs, and there is a possibility that contrast when an observer observes an image is uneven.

The 1 st substrate and the 2 nd substrate are sealed and bonded at the outer edge portion by a sealant. As the sealing agent also called a sealing agent, various resins such as epoxy resin, urethane resin, acrylic resin, vinyl acetate resin, olefin thiol resin, silicone resin, modified polymer resin, and the like, and thermosetting type, photocurable type, moisture curable type, anaerobic curable type, and the like can be used. The electrolyte may contain a columnar structure as necessary. The columnar structure is composed of columnar structures such as columnar bodies, quadrangular columnar bodies, elliptic columnar bodies, and trapezoidal columnar bodies, which provide strong self-holding property (strength) between substrates and are arranged at a constant interval according to a predetermined pattern such as a grid arrangement. Further, the patterns may be arranged at predetermined intervals. Preferably, the columnar structures are not arranged randomly, but are arranged so that the interval between the substrates can be appropriately maintained and light passing through the light control device is not hindered, such as an arrangement with equal intervals, an arrangement with gradually changing intervals, and an arrangement with a predetermined arrangement pattern repeated at a constant cycle. A spacer may be disposed between the pair of substrates to uniformly maintain a gap between the substrates. As the separator, a resin or inorganic oxide sphere can be exemplified. In addition, a spacer coated with a thermoplastic resin on the surface can be suitably used. In order to uniformly maintain the gap between the substrates, only the columnar structure may be disposed, both the spacer and the columnar structure may be disposed, or only the spacer may be disposed instead of the columnar structure. The diameter of the spacer is set to be equal to or less than the height of the columnar structure when used together with the columnar structure, and preferably equal to the height of the columnar structure. When the columnar structure is not arranged, the diameter of the spacer corresponds to the thickness of the gap between the pair of substrates.

The 1 st electrode is preferably formed of a nanowire, and the average diameter of the nanowire is preferably 1 μm or less, preferably 0.5 μm or less. It is desirable that the average length of the nanowires (average length in the long axis direction) is 1 × 10 ^-6 m is more than and 5 x 10 ^-4 m is less than or equal to, preferably 5X 10 ^-6 m or more and 2.5X 10 ^-4 m or less, more preferably 1X 10 ^-5 mm or more and 1X 10 ^-4 m is less than or equal to m. In addition, the average diameter (average length in the short axis direction) of the nanowire was 1 μm (1 × 10) as described above ^-6 m) below (a), and (b) below,but is desirably preferably 5X 10 ^-9 m is more than and 5 x 10 ^-7 m is less than or equal to, more preferably 1X 10 ^-8 m is more than or equal to 1 multiplied by 10 ^-7 m is preferably 1X 10 or less ^-8 m is more than and 5 x 10 ^-8 m is less than or equal to m. If the average length of the nanowires is less than 1X 10 ^-6 When the 1 st electrode is formed by, for example, a coating method or a printing method, the number of contacts between nanowires is reduced, and conduction becomes difficult, and as a result, the resistance of the 1 st electrode may be increased. On the other hand, in excess of 5X 10 ^-4 When m is used, the nanowires are liable to be excessively entangled, and the dispersion stability may be deteriorated. The average diameter of the nano-wire exceeds 1 x 10 ^-6 When m is used, the properties as a conductor are good, but the haze due to light scattering is significant, and the transparency may be lost. On the other hand, the average diameter of the nanowires is less than 5 x 10 ^-9 When m is used, the transparency is good, but the conductivity may be deteriorated by oxidation.

As the conductive material constituting the 1 st electrode, any material can be used as long as it is an electrochemically stable conductive material, and specific examples thereof include metal materials such as silver (Ag), bismuth (Bi), platinum (Pt), chromium (Cr), aluminum (Al), cobalt (Co), and palladium (Pd), and among these, silver (Ag) is preferably used for the following reason. The 1 st electrode can be obtained by, for example, applying or printing a material obtained by dispersing nanowires made of a conductive material in a solvent onto the 1 st substrate and performing a heat treatment, or applying or printing a material obtained by dispersing fine particles made of a conductive material in a solvent onto the 1 st substrate and performing a heat treatment, and in these cases, the 1 st electrode is not patterned. Specifically, the portion of the 1 st electrode occupying the active area of the dimming device is preferably not patterned. Here, the effective region of the light control device is the same as or larger than a projection image of the 2 nd deflection unit described later. The same applies to the following. That is, the size of the projection image of the 1 st electrode not patterned is preferably the same as or larger than the projection image of the 2 nd deflection unit described later. Further, a portion of the 1 st electrode which is drawn out to the outside can be made of a conductive material. Alternatively, the pattern can be obtained by forming a metal thin film on the 1 st substrate and then patterning the metal thin film randomly (or irregularly). In addition, carbon (for example, carbon nanotubes) can be used as the conductive material, and in this case, the conductive material may be formed into ink using a resin and a solvent and printed on the 1 st substrate.

By forming the 1 st electrode by a coating method or a printing method using nanowires, the 1 st electrode in which nanowires are randomly (or irregularly or disorderly) arranged can be obtained, and as a result, the diffraction phenomenon of light passing through the 1 st electrode can be effectively prevented. Further, as described above, by setting the average diameter of the nanowires to 1 μm or less, preferably 0.5 μm or less, it is possible to more effectively prevent the diffraction phenomenon of light passing through the 1 st electrode and to reduce the light scattering intensity. For example, when a fluorescent lamp is observed by a light control device, if a diffraction phenomenon occurs in light passing through the 1 st electrode, a problem occurs in that the fluorescent lamp looks iridescent and the visual field is extremely poor, but the occurrence of such a problem can be reliably avoided by preventing the diffraction phenomenon from occurring in light passing through the 1 st electrode.

The 2 nd electrode may be a so-called transparent electrode, and specifically may be an Indium Tin Oxide (ITO) containing In doped with Sn ₂ O ₃ Crystalline ITO and amorphous ITO), fluorine-doped SnO ₂ (FTO), IFO (F-doped In) ₂ O ₃ ) Antimony doped SnO ₂ (ATO)、SnO ₂ ZnO (including Al-doped ZnO and B-doped ZnO), Indium-Zinc composite Oxide (IZO), spinel-type Oxide, and Oxide having YbFe ₂ O ₄ And structured oxides, conductive polymers such as polyaniline, polypyrrole, and polythiophene, but the present invention is not limited to these, and 2 or more kinds of these may be used in combination. The 2 nd electrode can be formed by a physical vapor deposition method (PVD method) such as a vacuum deposition method or a sputtering method, various chemical vapor deposition methods (CVD methods), various coating methods, or the like. The electrode can be patterned by any method such as an etching method, a lift-off method, or a method using various masks.

A specific example of the light control device 800 of example 9 is described below.

The dimming device 800 of embodiment 9 comprises:

a transparent 1 st substrate 801 and a transparent 2 nd substrate 803 facing the 1 st substrate 801;

a1 st electrode 802 provided on the 1 st substrate 801;

a 2 nd electrode 804 disposed on the 2 nd substrate 803; and

an electrolyte 805 containing metal ions sealed between the 1 st substrate 801 and the 2 nd substrate 803,

the 1 st electrode 802 is made of a conductive material in a thin wire form,

the 2 nd electrode 804 is formed of a transparent electrode layer.

The 1 st substrate 801 is disposed closer to the viewer than the 2 nd substrate 803. The 1 st electrode 802 is composed of a nanowire having an average diameter of 1 μm or less. More specifically, the conductive material constituting the 1 st electrode 802 is silver (Ag), and the 1 st electrode 802 is composed of silver nanowires. The average length of the silver nanowires (length in the major axis direction) and the average diameter of the nanowires (length in the minor axis direction) were 4 × 10 ^-4 m、5×10 ^-7 And m is selected. The 1 st electrode 802 is formed by randomly (or irregularly, disorderly) arranging silver nanowires, and is schematically shown in a layered state in the drawing. The metal ions are composed of silver (Ag) ions, and the electrolyte 805 contains a supporting electrolyte salt composed of LiI. By making the metal ions silver ions and making the 2 nd electrode 804 of silver, that is, by making the metal material and the metal ions constituting the 2 nd electrode 804 of the same metal, an electrochemically stable electrode reaction can be realized. The 1 st substrate 801 and the 2 nd substrate 803 are made of glass having a thickness of 0.4mm, and the interval between the 1 st substrate 801 and the 2 nd substrate 803 is 100 μm. The 2 nd electrode 804 includes a transparent electrode made of indium-tin composite oxide (ITO), and is formed by a combination of a PVD method such as a sputtering method and a lift-off method. The 1 st electrode 802 is not patterned, nor the 2 nd electrode 804, which are so-called beta electrodes. Specifically, the portions of the 1 st and 2

nd electrodes

802, 804 occupying the active area of the dimming device 800 are not patterned. Here, the effective area of the light control device 800 refers to the 2

nd deflection units

140 and 340 are the same or larger than the projected image. More specifically, the size of the projection image of the 1 st electrode 802 and the 2 nd electrode 804, which are not patterned, is larger than the projection image of the 2

nd deflection unit

140, 340. Further, a portion of the 1 st electrode 802 drawn to the outside is made of another conductive material (not shown). In addition, a portion where the 2 nd electrode 804 is drawn to the outside is patterned. The 1 st electrode 802 and the 2 nd electrode 804 are connected to the control device 18 via a connector and a wire, not shown. Outer edge portions of the 2

substrates

801 and 803 are sealed with a sealant 806. The 1 st substrate 801 of the light control device 800 is fixed to the light guide plate 121 by a sealing member, and a gap is formed between the 1 st substrate 801 and the light guide plate 121. The 1 st substrate 801 of the light control device 800 is set to have a length similar to that of the light guide plate 121, and the 1 st substrate 801 of the light control device 800 is fixed to the light guide plate 121 by a sealing member. The sealing member is disposed at the outer edge of the 1 st substrate 801.

The 1 st electrode 802 can be obtained by printing a material in which silver nanowires are dispersed in a solvent onto the 1 st substrate 801 according to a screen printing method and performing heat treatment.

A barrier layer (not shown) (for example, made of an inorganic material, specifically, alumina) may be formed between the 1 st substrate 801 and the 1 st electrode 802, and between the 2 nd substrate 803 and the 2 nd electrode 804. Further, a SiN layer or SiO layer may be formed between the 2 nd electrode 804 and the barrier layer ₂ Layer of Al ₂ O ₃ Layer, TiO ₂ A protective layer comprising a layer or a laminated film thereof. By forming the protective layer, the light control device can be provided with ion blocking properties, water resistance, moisture resistance, and scratch resistance that prevent the passage of ions.

1 part by mass of polyether having a molecular weight of about 35 ten thousand, 10 parts by mass of dimethyl sulfoxide (DMSO), 1.7 parts by mass of sodium iodide, and 1.7 parts by mass of silver iodide were mixed, heated to 120 ℃, and prepared into a uniform solution. In addition, triethanolamine, coumarin (see the following formula) and benzimidazole (see the following formula) were added to the solution, thereby obtaining an electrolyte 805. The solution was added so that triethanolamine, coumarin and benzimidazole were 10 g, 1.5 g and 1.5 g, respectively, per 1 liter of the solution.

Further, the 1 st substrate 801 having the 1 st electrode 802 and the 2 nd substrate 803 having the 2 nd electrode 804 are sealed at their outer edges with an olefin-based sealant 806. The sealant 806 contains 10 vol% of a separator (not shown) composed of plastic spherical beads having an average particle diameter of 100 μm. Further, an opening (injection port) is provided in a part of the sealant. Further, inside the battery cell to which the 1 st substrate 801 and the 2 nd substrate 803 obtained in this way are bonded, an electrolyte 805 containing AgI is vacuum-injected from an opening provided in a sealant, and then the opening is sealed, thereby obtaining the light control device 800.

Coloring and decoloring of the light control device (specifically, an electrodeposition type light control device) are caused by precipitation of silver on the 2 nd electrode 804 and dissolution of silver into the electrolyte 805 based on the voltage application to the 1 st electrode 802 and the 2 nd electrode 804. In addition, this enables control of the light transmittance of the light control device 800. Specifically, when a relatively positive voltage is applied to the 1 st electrode 802 and a relatively negative voltage is applied to the 2 nd electrode 804, the voltage applied to the 2 nd electrode 804 is changed according to the voltage applied to the 1 st electrode 802 and the voltage applied to the 2 nd electrode 804

Ag ⁺ +e ^- →Ag

This reaction causes silver to precipitate and form a thin layer of silver on the 2 nd electrode 804. Therefore, the light transmittance of the light control device 800 is low. On the other hand, in the reverse direction, when a negative voltage is applied to the 1 st electrode 802 and a positive voltage is applied to the 2 nd electrode 804, a voltage is generated

Ag→Ag ⁺ +e ^-

In this reaction, silver deposited on the 2 nd electrode 804 dissolves in the electrolyte 805. Thereby, the 2 nd electrode 804 in a colored state becomes a transparent state. Therefore, the light transmittance in the light control device 800 has a high value. The light transmittance in the light control device 800 can be controlled according to the values of the voltages applied to the 1 st electrode 802 and the 2 nd electrode 804 and the time of application. The voltages applied to the 1 st electrode 802 and the 2 nd electrode 804 can be controlled by an observer operating a control knob provided to the control device 18. That is, the observer may observe the images from the

optical devices

120 and 320 and adjust the light transmittance of the light control device 800 to improve the contrast of the images. As a result of various tests, it is expected that the maximum light transmittance of the light control device 800 is 50% or more (preferably 50% or more and 99% or less), and the minimum light transmittance is 30% or less (preferably 1% or more and 30% or less).

In the display device of example 9, the light control device is constituted by a so-called electrodeposition type light control device including the 1 st electrode made of a thin wire-like conductive material and the 2 nd electrode made of a transparent electrode layer, and thus the following display device can be provided: the image display device can provide a high contrast to an image observed by an observer, and can sufficiently increase the amount of external light incident on the image display device with low power consumption. Further, by forming the 1 st electrode by a printing method using silver nanowires, the 1 st electrode in which silver nanowires are randomly (or irregularly, disorderly) arranged can be obtained, and as a result, the diffraction phenomenon of light passing through the 1 st electrode can be effectively prevented. Further, by setting the average diameter of the silver nanowires as described above, the diffraction phenomenon of light passing through the 1 st electrode can be more effectively prevented, and the light scattering intensity can be reduced.

The present disclosure has been described above based on preferred embodiments, but the present disclosure is not limited to these embodiments. The configurations and structures of the display device (head mounted display) and the image display device described in the embodiments are examples, and can be changed as appropriate. For example, a surface relief type hologram may be disposed on the light guide plate (see U.S. Pat. No. 20040062505a 1). The optical device 320 may be configured such that the transmission type diffraction grating element constitutes the diffraction grating element, or alternatively, one of the 1 st deflection unit and the 2 nd deflection unit is configured by a reflection type diffraction grating element and the other is configured by a transmission type diffraction grating element. Alternatively, the diffraction grating element may be a reflection type blazed diffraction grating element. The display device of the present disclosure can also be used as a stereoscopic display device. In this case, the polarizing plate or the polarizing film may be detachably attached to the optical device or may be bonded to the optical device as needed.

In the embodiment, the

image forming apparatuses

111 and 211 are described as displaying a monochromatic (for example, green) image, but the

image forming apparatuses

111 and 211 may also display a color image, and in this case, for example, the light sources may be configured by light sources emitting red, green, and blue light, respectively. Specifically, for example, white light may be obtained by mixing red light, green light, and blue light emitted from a red light emitting element, a green light emitting element, and a blue light emitting element, respectively, using a light pipe to make the luminance uniform. In this case, the light passing through the light control device can be colored in a desired color by the light control device, and in this case, the color colored by the light control device can be changed. Specifically, for example, a light control device colored red, a light control device colored green, and a light control device colored blue may be stacked.

The image display devices described in embodiments 1 to 9 can be modified as described below. That is, as shown in a schematic view seen from above in fig. 26, a light blocking member 903 for preventing light from leaking out of the light guide plate 321 and reducing light utilization efficiency is formed on the outer surface of the light control device 700' facing the 1 st diffraction grating member 330.

Alternatively, the optical device in the image display device described in embodiments 3 to 4 may be modified as described below. That is, as shown in a conceptual diagram of an optical device in a modification of the display device of example 1 in fig. 27A, the hologram diffraction grating on the light incident side can be used as the transmission type diffraction grating element 330B, and the hologram diffraction grating on the light emitting side can be used as the reflection type diffraction grating element 340A. Light enters the transmission type diffraction grating element 330B, and light exits the transmission type diffraction grating element 340B. Alternatively, as shown in a conceptual diagram of an optical device in a modification of the display device of embodiment 1 in fig. 27B, the hologram diffraction grating on the light incident side may be a reflection-type diffraction grating element 330A, and the hologram diffraction grating on the light emitting side may be a transmission-type diffraction grating element 340B. Alternatively, as shown in a conceptual diagram of an optical device in a modification of the display device of embodiment 1 in fig. 27C, the hologram diffraction grating on the light incident side may be a transmission type diffraction grating element 330B, and the hologram diffraction grating on the light emitting side may be a transmission type diffraction grating element 340B. Alternatively, as shown in a conceptual diagram of an optical device in a modification of the display device of embodiment 1 in fig. 27D, the hologram diffraction grating on the light incident side may be a reflection-type diffraction grating element 330A and a transmission-type diffraction grating element 330B, and the hologram diffraction grating on the light emitting side may be a reflection-type diffraction grating element 340A. Alternatively, as shown in a conceptual diagram of an optical device in a modification of the display device of example 1 in fig. 27E, the hologram diffraction grating on the light incident side may be a reflection-type diffraction grating element 330A and a transmission-type diffraction grating element 330B, and the hologram diffraction grating on the light emitting side may be a transmission-type diffraction grating element 340B. Alternatively, as shown in a conceptual diagram of an optical device in a modification of the display device of embodiment 1 in fig. 27F, the hologram diffraction grating on the light incident side may be a reflection-type diffraction grating element 330A, and the hologram diffraction gratings on the light emitting side may be a reflection-type diffraction grating element 340A and a transmission-type diffraction grating element 340B. Alternatively, as shown in a conceptual diagram of an optical device in a modification of the display device of embodiment 1 in fig. 27G, the hologram diffraction grating on the light incident side may be a transmission type diffraction grating element 330B, and the hologram diffraction gratings on the light emitting side may be a reflection type diffraction grating element 340A and a transmission type diffraction grating element 340B. Alternatively, as shown in a conceptual diagram of an optical device in a modification of the display device of embodiment 1 in fig. 27H, the hologram diffraction gratings on the light incident side may be a reflection-type diffraction grating element 330A and a transmission-type diffraction grating element 330B, and the hologram diffraction gratings on the light emitting side may be a reflection-type diffraction grating element 340A and a transmission-type diffraction grating element 340B.

The image display devices described in embodiments 3 to 4 can be modified as described below. That is, as shown in a conceptual diagram of an optical device and a light control device in a modification of the display device of example 1 in fig. 28, a1 st reflection type volume hologram diffraction grating 351, a 2 nd reflection type volume hologram diffraction grating 352, and a 3 rd reflection type volume hologram diffraction grating 353 may be provided. With the 1 st reflection type volume hologram diffraction grating 351, the interference fringes of the diffraction grating member extend substantially in the Y direction. With the 2 nd reflection type volume hologram diffraction grating 352, the interference fringes of the diffraction grating member extend in an oblique direction. With the 3 rd reflection type volume hologram diffraction grating 353, the interference fringes of the diffraction grating member extend substantially in the X direction. The light beams emitted from the

image forming apparatuses

111, 111', 211 are diffracted in the X direction by the 1 st reflection type volume hologram diffraction grating 351, propagate through the light guide plate 321, and enter the 2 nd reflection type volume hologram diffraction grating 352. Then, the light is diffracted obliquely downward by the 2 nd reflection type volume hologram diffraction grating 352, and enters the 3 rd reflection type volume hologram diffraction grating 352. Then, the 3 rd reflection type volume hologram diffraction grating 353 diffracts the light in the Z direction and enters the pupil 21 of the observer 20.

Fig. 29A and 29B are schematic diagrams showing a modification of the optical device constituting the optical device of the 2 nd structure described in example 5, as viewed from above.

In the example shown in fig. 29A, light from the light source 601 enters the light guide member 602 and collides with the polarization beam splitter 603 provided in the light guide member 602. Of the light from the light source 601 that impinges on the polarization beam splitter 603, the P-polarized light component passes through the polarization beam splitter 603, and the S-polarized light component is reflected by the polarization beam splitter 603 and directed to a liquid crystal display device (LCD)604 formed of an LCOS as a light valve. An image is formed by a liquid crystal display device (LCD) 604. Since the polarized light component of the light reflected by the liquid crystal display device (LCD)604 is occupied by the P-polarized light component, the light reflected by the liquid crystal display device (LCD)604 passes through the

polarization beam splitters

603 and 605, passes through the 1/4 wavelength plate 606, hits the reflection plate 607, is reflected, passes through the 1/4 wavelength plate 606, and is directed to the polarization beam splitter 605. The polarized light component of the light at this time is occupied by the S-polarized light component, and is reflected by the polarization beam splitter 605 and directed toward the pupil 21 of the observer 20. As described above, the image forming apparatus is configured by the light source 601 and the liquid crystal display device (LCD)604, the optical device is configured by the light guide member 602, the

polarizing beam splitters

603, 605, and 1/4, the wavelength plate 606, and the reflection plate 607, and the polarizing beam splitter 605 corresponds to a virtual image forming region of the optical device.

In the example shown in fig. 29B, light from the image forming device 611 travels through the light guide 612 and impinges on the half mirror 613, a part of the light passes through the half mirror 613, impinges on the reflective plate 614, is reflected, impinges on the half mirror 613 again, and a part of the light is reflected by the half mirror 613 and travels toward the pupil 21 of the observer 20. The optical device is configured of the light guide 612, the semi-transmissive mirror 613, and the reflector 614 as described above, and the semi-transmissive mirror 613 corresponds to a virtual image forming region of the optical device.

Alternatively, fig. 30A and 30B are schematic diagrams illustrating an optical device in another modification of the display device of example 5, as viewed from above and from the side. The optical device is composed of a 6-sided prism 622 and a convex lens 625. Light emitted from image forming apparatus 621 enters prism 622, impinges on prism surface 623, is reflected, travels through prism 622, impinges on prism surface 624, is reflected, and reaches pupil 21 of observer 20 via convex lens 625. Prism faces 623 and 624 are additionally tilted in opposing directions, and prism 622 is trapezoidal in planar shape, specifically, isosceles trapezoidal. A mirror coating is applied to prism faces 623, 624. If the thickness (height) of the portion of the prism 622 facing the pupil 21 is made thinner than 4mm, which is the average pupil diameter of a human being, the observer 20 can view an image of the outside world and a virtual image from the prism 622 in an overlapping manner.

According to circumstances, the following may also be employed: the light blocking ratio of the light control device is controlled from the 1 st predetermined region of the virtual image formation region opposing region toward the 2 nd predetermined region of the virtual image formation region opposing region by dividing the 1 st electrode and/or the 2 nd electrode into a plurality of blocks and controlling the light blocking ratio in each block. Alternatively, or in addition, the following may also be employed: the light blocking ratio in the plurality of regions of the light control device is independently controlled by using the 1 st electrode or the 2 nd electrode as a strip-shaped electrode or a mesh-shaped electrode, or by forming a strip-shaped auxiliary electrode or a mesh-shaped auxiliary electrode on the 1 st electrode or the 2 nd electrode, and the light blocking ratio of the light control device from the 1 st predetermined region of the virtual image formation region opposing region toward the 2 nd predetermined region of the virtual image formation region opposing region is controlled.

The present disclosure can also adopt the following configurations.

[A01] Light adjusting device

A light control device is provided with:

a1 st electrode;

a 2 nd electrode facing the 1 st electrode;

a control unit for controlling coloring/decoloring of the light adjusting layer,

the control part controls:

(A) charging of a capacitor using a secondary battery; and

[A02] In the dimming device according to [ a01],

the control part also controls

[A03] In the light control device described in [ a02], after a predetermined time has elapsed from the start of coloring of the light control layer, voltage application to the 1 st electrode and the 2 nd electrode by the secondary battery is performed, and after a predetermined time (coloring/predetermined time) has elapsed, voltage application to the 1 st electrode and the 2 nd electrode by the secondary battery is stopped.

[A04] In the light control device according to [ a02] or [ a03], after a predetermined time has elapsed from the start of decoloring with the light control layer, voltage application to the 1 st electrode and the 2 nd electrode by the secondary battery is performed, and after a predetermined time (decoloring/predetermined time) has elapsed, voltage application to the 1 st electrode and the 2 nd electrode by the secondary battery is stopped.

[A05] In the light control device according to [ a02] or [ a03], after a predetermined time has elapsed from the start of decoloring of the light control layer, the application of the voltage to the 1 st electrode and the 2 nd electrode by the secondary battery is suspended.

[A06] In the light control device described in [ A01] to [ A05], the control unit applies a positive potential to one of the 1 st electrode and the 2 nd electrode and a negative potential to the other of the 1 st electrode and the 2 nd electrode during coloring of the light control device,

the control unit applies a voltage having a polarity opposite to that of the voltage applied to the 1 st electrode and the 2 nd electrode during coloring of the light control device during color erasing of the light control device.

[A07]In [ A01]]To [ A06]]In the light control device according to any one of the above, Q is an amount of charge that provides a desired light transmittance to the light control layer at the time of coloring ₀ The charge amount of the charged capacitor is Q ₁ A predetermined time T will elapse from the start of coloring or decoloring of the light control layer ₀ The charge amount of the capacitor is set to Q ₂ To satisfy

0.4<(Q ₁ -Q ₂ )/Q ₀

In the embodiment, the control unit controls the voltage applied to the capacitor and the 1 st and 2 nd electrodes.

[A08] In the dimming device described in [ A07], to satisfy

1.0≤(Q ₁ -Q ₂ )/Q ₀ ≤10.0

[A09] The light control device according to [ A07] or [ A08], wherein

T is not less than 0.1 (second) ₀ Less than or equal to 12 seconds.

[A10] In the light control device according to any one of [ a01] to [ a09], when a voltage is applied to the 1 st electrode and the 2 nd electrode, a current flows through the light control layer.

[B01] In the dimming device according to any one of [ a01] to [ a10],

the light control layer has a laminated structure of a reduction coloring layer made of tungsten oxide, an electrolyte layer made of tantalum oxide, and an oxidation coloring layer containing iridium atoms.

[B02] In the light control device according to [ B01], the oxidation-colored layer is made of an iridium tin oxide-based material.

[B03] In the light control device according to [ B01] or [ B02], a moisture retaining member is disposed at least between the 2 nd electrode and the 2 nd substrate.

[B04] In the light control device according to [ B03], an end surface of the water retaining member is exposed to the outside.

[B05] The light control device according to [ B04], further comprising a sealing member provided at an edge portion of the 1 st substrate,

a moisture holding member extending portion extending from the moisture holding member is disposed between the sealing member and the 2 nd substrate.

[B06] In the light control device described in [ B05], the 2 nd electrode is formed to extend from the light control layer to the 1 st substrate and to be separated from the 1 st electrode,

the moisture holding member covers at least the 2 nd electrode and the light modulating layer.

[B07] In the light control device according to [ B05] or [ B06], a part of the sealing member is constituted by the auxiliary electrode.

[B08] In the light control device according to [ B07], the auxiliary electrode includes a1 st auxiliary electrode formed on the 1 st electrode and a 2 nd auxiliary electrode formed on the 2 nd electrode separately from the 1 st auxiliary electrode.

[B09] In the light control device according to [ B05] or [ B06], the sealing member is made of resin.

[B10]In [ B09]In the light control device, the Young's modulus of the resin constituting the sealing member is 1 × 10 ⁷ Pa or less.

[B11] The light control device according to [ B05] or [ B06], wherein an auxiliary electrode is provided at least inside a part of the sealing member.

[B12] In the light control device according to [ B11], the auxiliary electrode includes a1 st auxiliary electrode formed on the 1 st electrode and a 2 nd auxiliary electrode formed on the 2 nd electrode separately from the 1 st auxiliary electrode.

[B13] In the light control device according to [ B05] or [ B06], the sealing member is formed of a convex portion provided at an edge portion of the 1 st substrate.

[B14] In the light control device according to [ B13], an auxiliary electrode is provided inside a part of the sealing member.

[B15] In the light control device according to [ B14], the auxiliary electrode includes a1 st auxiliary electrode formed on the 1 st electrode and a 2 nd auxiliary electrode formed on the 2 nd electrode separately from the 1 st auxiliary electrode.

[B16] The light control device according to any one of [ B05] to [ B15], wherein a cross-sectional shape of the sealing member is a shape that becomes narrower as it approaches the 2 nd substrate.

[B17] The light control device according to any one of [ B03] to [ B16], wherein an inorganic material film is formed on a surface of the 2 nd substrate facing the water holding member.

[B18]In [ B03]To [ B17]In the light control device of any one of the above, the young's modulus of a material constituting the water holding member is 1 × 10 ⁶ Pa or less.

[B19] In the light control device according to [ B18], the resin constituting the water retaining member is an acrylic resin, a silicone resin, or a polyurethane resin.

[C01] In the display device of any one of [ A01] to [ A10],

the dimming device includes:

a transparent 1 st substrate and a transparent 2 nd substrate facing the 1 st substrate;

a1 st electrode disposed on the 1 st substrate;

a 2 nd electrode disposed on the 2 nd substrate; and

an electrolyte sealed between the 1 st substrate and the 2 nd substrate and containing metal ions,

the 1 st electrode is made of a conductive material in the form of a thin wire,

the 2 nd electrode is formed of a transparent electrode layer.

[C02] In the display device according to [ C01], the 1 st substrate is disposed closer to the viewer than the 2 nd substrate.

[C03] In the display device described in [ C02], the 1 st electrode is composed of a nanowire.

[C04] In the display device described in [ C03], the nanowires have an average diameter of 1 μm or less.

[C05] In the display device according to any one of [ C01] to [ C04], the 1 st electrode is made of silver.

[C06] In the display device of any one of [ C01] to [ C05], the 2 nd electrode is not patterned in an active area of the dimming device.

[C07] In the display device of any one of [ C01] to [ C06], the metal ion is composed of a silver ion,

the electrolyte contains at least 1 salt selected from the group consisting of LiX, NaX, and KX (wherein X is a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom).

[C08] In the display device according to any one of [ C01] to [ C07], coloring and decoloring of the light control device are caused by precipitation of the metal on the 2 nd electrode and dissolution of the metal in the electrolyte based on voltage application to the 1 st electrode and the 2 nd electrode.

[D01] In the dimming device according to any one of [ a01] to [ C08],

the effective area of the light modulation layer is defined as A (mm) ² ) When the capacitance of the capacitor is C (farad), the capacitance satisfies

C/A>1×10 ^-6 (F/mm ² )。

[D02] In the dimming device according to any one of [ a01] to [ D01], the capacitor is configured by a plurality of capacitors connected in parallel.

[D03] In the dimming device according to any one of [ a01] to [ D02],

the control circuit includes:

and a voltage control circuit for controlling voltages applied to the 1 st electrode and the 2 nd electrode from the capacitor and the secondary battery.

[D04] The light control device according to any one of [ a01] to [ D03], wherein the secondary battery is a lithium ion battery.

[D05] The display device according to any one of [ A01] to [ D04], further comprising an illuminance sensor (ambient illuminance measurement sensor) for measuring illuminance of an environment in which the display device is placed,

the light transmittance of the light control device is controlled based on the measurement result of the illuminance sensor (ambient illuminance measurement sensor).

[D06] The display device according to any one of [ A01] to [ D05], further comprising an illuminance sensor (ambient illuminance measurement sensor) for measuring illuminance of an environment in which the display device is placed,

the brightness of an image formed by the image forming apparatus is controlled based on the measurement result of the illuminance sensor (ambient illuminance measurement sensor).

[D07] The display device according to any one of [ A01] to [ D06], further comprising a 2 nd illuminance sensor (transmitted light illuminance measurement sensor) for measuring illuminance based on light transmitted through the light control device from an external environment,

the light transmittance of the light control device is controlled based on the measurement result of the 2 nd illuminance sensor (transmitted light illuminance measurement sensor).

[D08] The display device according to any one of [ A01] to [ D07], further comprising a 2 nd illuminance sensor (transmitted light illuminance measurement sensor) for measuring illuminance based on light transmitted through the light control device from an external environment,

the brightness of an image formed by the image forming apparatus is controlled based on the measurement result of the 2 nd illuminance sensor (transmitted light illuminance measurement sensor).

[D09] In the display device according to [ D07] or [ D08], the 2 nd illuminance sensor (transmitted light illuminance measurement sensor) is disposed closer to the observer side than the optical device.

[D10] In the display device according to any one of [ D05] to [ D09], when a measurement result by the illuminance sensor (ambient illuminance measurement sensor) is equal to or greater than a predetermined value, the light transmittance of the light control device is set to be equal to or less than the predetermined value.

[D11] In the display device according to any one of [ D05] to [ D09], when a measurement result by an illuminance sensor (ambient illuminance measurement sensor) is equal to or less than a predetermined value, the light transmittance of the light control device is equal to or more than the predetermined value.

[D12] In the display device according to [ D07] or [ D08], when the measurement result of the 2 nd illuminance sensor (transmitted light illuminance measurement sensor) is equal to or greater than a predetermined value, the light transmittance of the light control device is set to be equal to or less than the predetermined value.

[D13] In the display device according to [ D07] or [ D08], when the measurement result of the 2 nd illuminance sensor (transmitted light illuminance measurement sensor) is equal to or less than a predetermined value, the light transmittance of the light control device is equal to or more than the predetermined value.

[D14] In the display device according to any one of [ a01] to [ D13], a maximum light transmittance of the light control device is 50% or more, and a minimum light transmittance of the light control device is 30% or less.

[D15] In the dimming device according to any one of [ a01] to [ D14], the dimming device is curved.

[D16] The light control device according to any one of [ a01] to [ D15], wherein the 1 st substrate and the 2 nd substrate are made of a plastic material.

[E01] Image display device

An image display device is provided with:

an image forming apparatus;

a light control device that is disposed so as to face at least the virtual image forming region and that adjusts the amount of external light incident from the outside,

the light control device is constituted by the light control device described in any one of [ a01] to [ D16 ].

[E02] Display device

A display device is provided with:

a frame to be worn on a head of an observer; and

an image display device mounted to the frame, wherein,

the image display device includes:

an image forming apparatus;

Description of the symbols

10 … frame, 10 ' … nose pad, 11 … front mirror, 11 ' … rim, 12 … hinge, 13 … leg, 14 … foot cover, 15 … wiring (signal line, power line, etc.), 16 … ear set, 16 ' … ear set wiring, 17 … camera, 18 … control device, 19 … mounting component, 20 … observer, 21 … pupil, 30 … control unit, 31 … secondary battery, 32 … control circuit, 32a … secondary battery control unit, 33 … capacitor (capacitance), 41 … 1 st switch unit, SW … second switch unit ₁ 、SW ₂ 、SW ₃ … switch section, 42 … 2 nd switch section, 50 … voltage control circuit (regulator), 60 … charging circuit, 61 … comparator, 62 … constant voltage IC (constant voltage IC) with current limiting function, 70A, 70B … light transmittance/polarity control circuit, 71A, 71B … operational amplifier, 100, 200, 300, 400, 500 … image display device, 111A, 111B, 111', 211A, 211B … image forming device, 112 … optical system (collimating optical system), 113, 213 … housing, 120, 320, 520 … optical device, 121, 321 … light guide plate, 122, 322 … light guide plate 1 st surface, 123, 323 of light guide plate, 2 nd surface, 124, 125 … light guide plate, 130 … 1 st deflection unit, 140 … nd 2 nd deflection unit (virtual image forming region), 330 … th 1 st deflection unit (1 st diffraction grating member), 330A, 340A … reflection type diffraction grating element, 340 … nd 2 nd deflection unit (2 nd diffraction grating member,330B, 340B … transmissive diffraction grating element, 351 … 1 st reflective volume hologram diffraction grating, 352 … 2 nd reflective volume hologram diffraction grating, 353 … rd 3 rd reflective volume hologram diffraction grating, 150 … reflective spatial light modulation device, 150' … organic EL display device, 151 … liquid crystal display device (LCD), 152 … semi-transmissive Polarizing Beam Splitter (PBS), 153 … light source, 251A, 251B … light source, 252 … collimating optical system, 253 … scanning unit, 254 … optical system (relay optical system), 256 … total reflection mirror, 530A, 530B … semi-transmissive mirror, 601 … light source, 602 … light guide, 603, … polarizing beam splitter, … liquid crystal display device, 606 … 1/4 wavelength plate, 607 … reflective plate, 611 82604 image forming device, 612 light guide …, 612, 613 … mirror, 614 … reflective plate, 621 … image forming device, 622 … prism, 623, 624 … prism surface, 625 … convex lens, 700' … light adjusting device, 701 … virtual image forming region opposing region, 711a … 1 st substrate, 711B … nd substrate, 712a … 1 st electrode, 712B … nd electrode, 713 … WO2 ₃ Layer (reduction coloring layer), 714 … Ta ₂ O ₅ Layer (electrolyte layer), 715 … Ir _X Sn _1-X An O layer (oxidation-coloring layer), 716 … light modulation layer, 719a … protective layer, 719B … base layer, 719C … sealing agent, 719D … adhesive, 721 … moisture holding member, 722 … moisture holding member extension, 723 … sealing member, 800 … light modulation device, 801 … 1 st substrate, 802 … 1 st electrode, 803 … nd 2 substrate, 804 … nd 2 electrode, 805 … electrolyte, 806 … sealant, 901 … illuminance sensor (ambient illuminance measuring sensor), 902 … nd 2 illuminance sensor (transmitted light illuminance measuring sensor), 903 … light shielding member, 1001 … battery unit (battery pack), 1002 … magnesium secondary battery, 1010 … controller, 1011 … memory, 1012 … voltage measuring portion, … current measuring portion, 1014 … current detecting resistor, … temperature, 361016 measuring portion, 1020 temperature detecting element, … switch control portion, 361021 … switch portion, 361015 charge control switch portion, 1024 … discharge control switch, 1023, 1025 … diode, 1031 … anode terminal, 1032 … cathode terminal, CO, DO … control signal

Claims

1. A light control device is provided with:

a1 st electrode;

a 2 nd electrode facing the 1 st electrode;

the control part controls:

(A) charging of a capacitor using a secondary battery; and

2. The dimming device of claim 1,

the control part also controls

3. The dimming device of claim 1,

the control unit applies a voltage having a polarity opposite to that of the 1 st electrode and the 2 nd electrode when the light control device is used for color erasing.

4. The dimming device of claim 1,

q is the amount of charge for providing a desired light transmittance to the light-adjusting layer at the time of coloring ₀ Let the charge amount of the capacitor be Q ₁ A predetermined time T will elapse from the start of coloring or decoloring of the light control layer ₀ The charge amount of the capacitor is set to Q ₂ To satisfy

0.4<(Q ₁ -Q ₂ )/Q ₀

5. A dimming device as claimed in claim 4, wherein to satisfy

1.0≤(Q ₁ -Q ₂ )/Q ₀ ≤10.0

6. The dimming device of claim 4, wherein

T is not less than 0.1 (second) ₀ Less than or equal to 12 seconds.

7. The dimming device of claim 1,

when a voltage is applied to the 1 st electrode and the 2 nd electrode, a current flows through the light control layer.

8. The dimming device of claim 1,

9. The dimming device of claim 8,

the oxidation coloring layer is made of an iridium tin oxide material.

10. The dimming device of claim 1,

a moisture holding member is disposed at least between the 2 nd electrode and the 2 nd substrate.

11. The dimming device of claim 1,

in the effective area of the light-modulating layerIs set to A (mm) ² ) When the capacitance of the capacitor is C (farad), the capacitance satisfies

C/A>1×10 ^-6 (F/mm ² )。

12. The dimming device of claim 1,

the capacitor is formed of a plurality of capacitors connected in parallel.

13. The dimming device of claim 1,

the control circuit includes:

14. The dimming device of claim 1,

the secondary battery is constituted by a lithium ion battery.

15. An image display device is provided with:

an image forming apparatus;

the dimming device is constituted by the dimming device according to any one of claims 1 to 14.

16. A display device is provided with:

a frame to be worn on a head of an observer; and

an image display device mounted on the frame, wherein,

the image display device includes:

an image forming apparatus;