JP6807687B2 - Lighting device and liquid crystal display device - Google Patents

Description

The present invention relates to a lighting device and a liquid crystal display device using an electrodeposition element.

The invention of a high-contrast backlight applied to a keypad portion of a mobile phone or the like is disclosed (see, for example, Patent Document 1). In the backlight described in Patent Document 1, the ambient brightness is detected by an optical sensor, and the electrochromic layer is switched to a transparent state or a reflective state according to the brightness. Since the switching is performed entirely, it cannot be used for local dimming (partial dimming, partial drive) in a liquid crystal display device, for example.

Local dimming is a method of improving the contrast by individually controlling the amount of light emitted from LED (light emitting diode) elements arranged on the back side of a liquid crystal panel, and is a method of improving the contrast ratio of different areas in the same screen. It can be greatly enhanced.

It is said that the biggest difference between a direct type backlight and an edge type backlight is related to local dimming. The direct type, which allows easy local dimming, has become the mainstream of backlights by taking advantage of this strength.

For example, the edge type backlight adopts a structure in which the light emitted from the LED elements arranged above and below is guided to the central part by the light guide plate, and therefore, in principle, the light emitted from the backlight is divided into small pieces. Have difficulty. Therefore, even when local dimming is supported, it is difficult to improve the contrast performance as much as when local dimming is performed using a direct backlight. On the other hand, in the field of portable devices and notebook computers, there is a strong demand for thinning, and it is desirable to use an edge type backlight.

The electrochromic display element is a non-emission type display element that utilizes the phenomenon of color change of a substance due to an electrochemical reversible reaction (electrolytic redox reaction) by applying a voltage (energization).

Among electrochromic materials (materials that undergo an electrochemical oxidation or reduction reaction when a voltage is applied (energized), which causes discoloration such as color development or decolorization), a part of the material due to the oxidation or reduction reaction. However, for example, a material that precipitates / deposits on an electrode (electrodeposition) or disappears from the electrode is called an electrodeposition material. Further, an element using an electrodeposition material is called an electrodeposition element.

FIG. 15 is a schematic cross-sectional view showing a configuration example of an electrodeposition element.

The electrodeposition element is composed of, for example, an upper substrate 10a and a lower substrate 10b arranged so as to face each other substantially in parallel, and an electrolyte layer 15 arranged between the two substrates 10a and 10b.

The upper substrate 10a and the lower substrate 10b include an upper transparent substrate 11a and a lower transparent substrate 11b, respectively, and an upper transparent electrode 12a and a lower transparent electrode 12b formed on the transparent substrates 11a and 11b, respectively. The transparent electrodes 12a and 12b are electrodes having a smooth surface. The transparent electrodes 12a and 12b may be patterned electrodes or non-patterned electrodes (solid electrodes).

The electrolyte layer 15 is arranged in the inner region of the sealing material (sealing portion) 14 between the upper substrate 10a and the lower substrate 10b, and contains a silver-containing electrodeposition material (for example, AgNO ₃ ).

The electrodeposition element shown in FIG. 15 can be electrically switched between a transparent state and a mirror state by, for example, a DC voltage applied to the electrodes 12a and 12b.

As an example, when the lower transparent electrode 12b is grounded and a negative DC voltage is applied to the upper transparent electrode 12a, the silver ions contained in the electrolyte layer 15 become metal in the vicinity of the upper transparent electrode 12a (the electrode on the negative voltage side). It changes to silver and deposits and deposits on the electrode 12a to form a silver thin film (mirror surface). The silver thin film acts as a mirror surface and specularly reflects the light incident on it. The silver thin film disappears from the upper transparent electrode 12a with the passage of time by releasing the applied voltage or by applying a voltage having the opposite polarity. When no voltage is applied, the light incident on the electrodeposition element in which silver is not deposited on the transparent electrodes 12a and 12b is transmitted therethrough.

The electrodeposition element shown in FIG. 15 is used as a mirror device that commutatively realizes a transparent state and a mirror state (reflection state) by applying-no application of a DC voltage.

Special Table 2011-514984

An object of the present invention is to provide a high quality lighting device and a liquid crystal display device.

According to one aspect of the present invention, a light source, a first substrate which is arranged at a position where light emitted from the light source is incident from a side surface and has (i) a first electrode and a light extraction structure, and (ii) the first. An electrolyte layer containing a silver-containing electrodeposition material, which is arranged so as to face substantially parallel to one substrate and has a second electrode, and (iii) between the first substrate and the second substrate. The electrodeposition element has an electrodeposition element that extracts light incident from the side surface and traveling inside as illumination light, and the electrodeposition element is viewed from the normal direction of the first and second substrates. At that time, in the arrangement region of the electrolyte layer, the transparent state and the mirror state at the positions of the first pixel and the second pixel defined at the positions where the first electrode and the second electrode overlap can be switched independently of each other. The light extraction structure is arranged at the positions of the first and second pixels of the first substrate, and the light traveling inside is emitted from the positions of the first and second pixels of the second substrate. A lighting device that is extracted as illumination light is provided.

Further, according to another aspect of the present invention, the illuminating device, a liquid crystal cell arranged at a position where the illuminating light emitted from the illuminating device is incident, driving the liquid crystal cell, and being emitted from the illuminating device. Provided is a liquid crystal display device including a control device that controls to synchronize the emission regions of the illumination light.

Further, according to another aspect of the present invention, the illuminating device, the liquid crystal cell arranged at the position where the illuminating light emitted from the illuminating device is incident, and the emission region of the illuminating light emitted from the illuminating device are defined. A liquid crystal display device including a control device that controls according to the ambient brightness is provided.

According to the present invention, it is possible to provide a high quality lighting device and a liquid crystal display device.

1A and 1B are schematic plan views showing an upper substrate 20 and a lower substrate 30 of the lighting device according to the first embodiment, respectively, and FIGS. 1C and 1D show the lighting device according to the first embodiment, respectively. It is a schematic plan view and sectional view which shows the electrodeposition element used. FIG. 2 is a schematic cross-sectional view showing the lighting device according to the first embodiment. 3A and 3B are schematic cross-sectional views showing a fine concavo-convex film 60 arranged on the lower surface of the transparent substrate 31. 4A to 4C are schematic cross-sectional views showing the progress of light emitted from the light source 80. 5A to 5D are schematic perspective views showing a case where the number of pixels of the electrodeposition element is increased. 6A and 6B are schematic plan views showing the upper substrate 20 and the lower substrate 30 of the lighting device according to the second embodiment, respectively, and FIGS. 6C and 6D are the lighting devices according to the second embodiment, respectively. It is a schematic plan view and sectional view which shows the electrodeposition element used. FIG. 7 is a schematic cross-sectional view showing the lighting device according to the second embodiment. 8A-8D are schematic cross-sectional views showing the progress of light emitted from the light source 80. 9A and 9B are schematic views showing a part of the lighting device according to the first modification. 10A and 10B are schematic cross-sectional views showing a lighting device according to a second modification. FIG. 11 is a schematic cross-sectional view showing a lighting device according to a third modification. 12A is a schematic perspective view showing the liquid crystal display device according to the third embodiment, FIG. 12B is a schematic cross-sectional view showing the liquid crystal display element 100, and FIG. 12C is a schematic view showing the lighting device 200. Cross-sectional view. FIG. 13A is a schematic perspective view showing the liquid crystal display device according to the fourth embodiment, and FIG. 13B is a schematic view showing an example of an arrangement mode of the liquid crystal display elements 400f and 400r and the lighting device 500. 14A and 14B are schematic perspective views showing a liquid crystal display device according to a fifth embodiment, FIG. 14C is a schematic cross-sectional view showing a lighting device 700, and FIG. 14D is a reflection dot 740. It is a schematic cross-sectional view which shows the progress of the reflected light. FIG. 15 is a schematic cross-sectional view showing a configuration example of an electrodeposition element.

A method of manufacturing the lighting device according to the first embodiment will be described with reference to FIGS. 1A to 1D and FIG.

See FIG. 1A. For example, a transparent electrode (segment electrode) 22 is formed on a transparent substrate 21 which is a glass substrate with a transparent conductive material such as ITO (indium tin oxide). In the first embodiment, six transparent electrodes 22 electrically separated from each other are patterned on the transparent substrate 21. Each transparent electrode 22 has, for example, a rectangular shape having a length of 16000 μm (further terminal portion + 5000 μm) and a width of 14,000 μm, and the distance between the electrodes 22 adjacent to each other in the vertical and horizontal directions is 10 μm. Further, a metal film (reflection film) 23 is formed on one end side of the transparent substrate 21.

The metal film (reflection film) 23 is made of a metal such as Al or Ag. Other high reflectance metal materials may be used. It can also be made of a material other than metal, which has high reflectance.

See FIG. 1B. For example, a transparent electrode (common electrode) 32 is formed on a transparent substrate 31 which is a glass substrate with a transparent conductive material such as ITO. In the first embodiment, a rectangular transparent electrode 32 having a length of 32000 μm and a width of 42000 μm (further terminals +5000 μm) is patterned on the transparent substrate 31.

The patterns of the transparent electrodes 22 and 32 are not limited to these, and may be patterned into a smaller rectangular shape, for example. Further, for example, an active element such as a TFT (thin film transistor) may be used for the portion of the transparent electrode 22 pattern.

In this way, the upper substrate (segment substrate) 20 in which the transparent electrode 22 is formed on the transparent substrate 21 and the lower substrate (common substrate) 30 in which the transparent electrode 32 is formed on the transparent substrate 31 are produced.

See FIGS. 1C and 1D. Next, the upper and lower substrates 20 and 30 are arranged so that the transparent electrodes 22 and 32 face each other, and cell formation is performed.

Since a small cell is used for the lighting device according to the first embodiment, the main sealing material 40 to which the gap control agent having a diameter of 50 μm is added is used without spraying the gap control agent on the 20th and 30th surfaces of the substrate.

In the case of manufacturing a lighting device using a cell having a large area, the gap control agent is sprayed on the 20th and 30th surfaces of the substrate.

In that case, for example, a gap control agent having a diameter of several μm to several hundred μm is sprayed on one of the substrates 20 and 30 so as to be 1 to 3 pieces / mm ² as an example. Depending on the diameter of the gap control agent, it is desirable to set the spray amount so that it does not affect the display, for example. In the case of an electrodeposition element, even if there is some gap unevenness, the effect on the display is small, so the amount of the gap control agent sprayed is not very important. It is also possible to control the gap by means of protrusions such as ribs. When using a rib spacer, it is desirable that the aspect ratio of the protrusion is high.

A main seal pattern is formed on one of the substrates 20 and 30. In FIG. 1C, the formation position of the main seal pattern is shown with diagonal lines. In the first embodiment, the ultraviolet curable sealing material 40 is used. As the sealing material 40, a thermosetting type or ultraviolet + heat curing type sealing material may be used. As described above, a gap control agent having a diameter of 50 μm is added to the sealing material 40.

At least the seal pattern is irradiated with ultraviolet rays to cure the seal material 40. When a thermosetting type sealing material is used, heat treatment is performed after the substrates 20 and 30 are overlapped.

Subsequently, the electrolytic solution 50 containing the electrodeposition material is sealed between the substrates 20 and 30. In the first embodiment, the vacuum injection method is used. An ODF (one drop fill) method or a capillary injection method may be used. The above-mentioned sealing material 40 is preferably a sealing material (seal material that is not corroded) that can withstand the electrolytic solution 50 used. Further, as will be described later, the manufactured electrodeposition element is arranged on the optical path of the light emitted from the light source. Therefore, it is desirable that the sealing material 40 is transparent to the light emitted from the light source, for example, transparent to visible light. Therefore, for example, a sealant containing no filler, a fluorine-based sealant, or the like is preferably used.

The electrolytic solution 50 containing the electrodeposition material is prepared by using an electrodeposition material (AgNO _3, etc.), a mediator (CuCl _2, etc.), a supporting electrolyte (LiBr, etc.), a solvent (DMF (N, N-dimethylformamide), etc.). It is composed. In the first embodiment, in DMF as a solvent, the AgNO ₃ as electrodeposition material was added 350 mM, added LiBr as 750mM supporting electrolyte, the CuCl ₂ is added 30mM as a mediator. In order to gel the electrolyte, for example, 10 wt% of PVB (polyvinyl butyral) may be added as a host polymer. By gelling (making a gel-like electrolyte layer), the reflectance of the electrodeposition element in the mirror state can be improved. In the first embodiment, the electrolytic solution 50 that does not gel is used.

As the electrodeposition material (silver compound), silver nitrate (AgNO ₃ ), silver chloride, silver oxide, silver bromide, silver iodide and the like can be used. The concentration of the silver compound is preferably, for example, 5 mM or more and 500 mM or less, but is not particularly limited.

The supporting electrolyte is not limited as long as it promotes the oxidation-reduction reaction of the electrodeposition material, for example, lithium salt (LiCl, LiBr, LiI, LiBF ₄ , LiClO _4, etc.), potassium salt (KCl, KBr, KI, etc.). Etc.), sodium salts (NaCl, NaBr, NaI, etc.) can be preferably used. The concentration of the supporting electrolyte is preferably, for example, 10 mM or more and 1 M or less, but is not particularly limited.

The solvent is not limited as long as it can stably hold the electrodeposition material or the like. It is possible to use a polar solvent such as water or propylene carbonate, a non-polar organic solvent, an ionic liquid, an ionic conductive polymer, a polymer electrolyte, or the like. Specifically, in addition to DMF, propylene carbonate, dimethyl sulfoxide, tetrahydrofuran, acetonitrile, polyvinyl sulfuric acid, polystyrene sulfonic acid, polyacrylic acid and the like can be used.

1C and 1D are schematic plan views and cross-sectional views showing the electrodeposition element (mirror device) produced in this manner, respectively.

The electrodeposition elements shown in both figures are, for example, upper and lower substrates 20 and 30 arranged so as to face each other substantially in parallel, and an electrolyte solution (electrolyte layer) 50 arranged between both substrates 20 and 30. Including.

The upper and lower substrates 20 and 30 include transparent substrates 21 and 31 and transparent electrodes 22 and 32 formed on the transparent substrates 21 and 31, respectively. The upper substrate 20 further includes a metal film (reflection film) 23. The metal film (reflective film) 23 is arranged at least in a part of a region (outer region of the sealing material 40) protruding from the transparent substrate 31 on the transparent substrate 21.

The electrolyte solution (electrolyte layer) 50 containing the silver-containing electrodeposition material is sealed inside the region between the upper substrate 20 and the lower substrate 30 surrounded by the transparent sealing material (sealing portion) 40 (seal portion). Placed).

Pixels are defined at positions where the electrodes 22 and 32 overlap inside the area surrounded by the sealing material 40 (the area where the electrolytic solution 50 is arranged) in a plan view (when viewed from the normal direction of the substrates 20 and 30). To. In the first embodiment, there are six rectangular pixels arranged in 2 rows and 3 columns. The sizes of the six rectangular pixels are equal to each other.

When a voltage is applied (energized) between the substrates 20 and 30 (electrodes 22 and 32), AgNO ₃ (electrodeposition material) is applied to the electrodes 22 and 32 (pixel portion) on the side to which the negative voltage is applied. A thin film of derived silver is formed and acts as a mirror surface. The silver thin film disappears from the electrodes 22 and 32 when the applied voltage is released or a voltage having the opposite polarity is applied.

Since the six transparent electrodes 22 are electrically separated (independent) from each other, for example, a DC voltage is applied to each pixel with the upper substrate 20 on the negative voltage side and the lower substrate 30 on the positive voltage side. It is possible to control the formation and non-formation of a silver thin film.

As an example, the lower substrate 30 (transparent electrode 32) is grounded, and a negative DC voltage is applied to the upper substrate 20 (transparent electrode 22). When a voltage is applied to one or more of the six transparent voltages 22, a silver thin film is formed on the transparent electrode 22 (pixel portion) to which the voltage is applied, and its position is in a mirror state (a state of reflecting light). Other positions are in a transparent state (a state in which light is transmitted). Further, unless a voltage is applied to all the six transparent electrodes 22, a silver thin film is not formed on the upper substrate 20, for example, the entire area within the arrangement region of the electrolytic solution 50 (inside the region surrounded by the sealing material 40) is in a transparent state. It becomes. In this way, the formation position of the silver thin film (reflection region) can be electrically controlled in the arrangement region of the electrolytic solution 50 (in the region surrounded by the sealing material 40).

That is, in the electrodeposition element shown in FIGS. 1C and 1D, for example, the DC voltage applied to the transparent electrodes 22 and 32 electrically switches between the transparent state and the mirror state for each pixel, and all the pixels are made transparent. All pixels can be in a mirror state, some pixels can be in a transparent state, and the remaining pixels can be in a mirror state. The electrodeposition elements shown in FIGS. 1C and 1D are mirror devices capable of switching between a transparent state and a mirror state, for example, by controlling the non-application-application of voltage for each pixel.

See FIG. By adding the fine concavo-convex film 60, the reflector (reflection member) 70, and the light source 80 to the electrodeposition elements shown in FIGS. 1C and 1D, the lighting device according to the first embodiment is manufactured.

The fine concavo-convex film 60 has, for example, a refractive index substantially equal to that of the transparent substrate 31, and is located at the pixel position on the lower surface (the surface opposite to the electrolytic solution 50) of the lower substrate 30 (transparent substrate 31) as an example. Is placed including.

3A and 3B show schematic cross-sectional views of the fine concavo-convex film 60 arranged on the lower surface of the transparent substrate 31. The fine concavo-convex film 60 is provided with, for example, a triangular prism-shaped convex portion (see FIG. 3A) or a concave portion (see FIG. 3B), reflects light incident on these convex portions or concave portions (concave and convex structure), and is a lower substrate. It emits light in a direction intersecting the in-plane direction of 30 (transparent substrate 31). The intensity of the emitted light is the strongest in the normal direction of the lower substrate 30 (transparent substrate 31). The protrusions and recesses are arranged relatively sparsely at a position relatively close to the light source 80, and relatively densely at a position relatively far from the light source 80, for example. As a result, the in-plane uniformity of the emitted light intensity at the arrangement position of the fine concavo-convex film 60 is achieved.

The reflector 70 is made of, for example, Al or SUS and is arranged around the elect deposition element. In the example shown in this figure, the reflector 70 is arranged around the elect deposition element except for the periphery of the transparent substrate 21. Further, in relation to the fine concavo-convex film 60, the reflector 70 is arranged on the outside of the fine concavo-convex film 60 so as to cover, for example, the fine concavo-convex film 60. Further, the reflector 70 is fixed to the upper substrate 20 so as to be in contact with the metal film (reflection film) 23, and together with the upper substrate 20 and the like, one side (left side in FIG. 1C) side (seal material 40, lower) of the electrodeposition element. A space is defined on the outside of the side substrate 30).

The reflector 70 can be formed by using a plate-shaped member or a film having a high reflectance, for example, a reflectance of 90% or more, and reflects the light incident on the reflector 70 to reflect the light incident on the reflector 70 inside the electrodeposition element. It has a function of making it incident on.

The light source 80 is arranged in a space (side surface of the electrodeposition element) defined on one side of the electrodeposition element. For example, the metal film (reflecting film) 23 and the reflecting plate 70 are arranged around the light source 80 that is not on the electrodeposition element side. As the light source 80, a linear LED light source, a cold cathode fluorescent lamp (CCFL), or the like can be used. The linear LED light source is, for example, a light source in which point-shaped LED elements are arranged along one direction.

4A to 4C schematically show the progress of the light emitted from the light source 80. In FIG. 4A, for example, when all six pixel positions are in a transparent state, in FIG. 4B, of the six pixel positions, for example, the two pixel positions in the right column in FIG. 1C are in a transparent state, and the remaining four pixel positions are set in a transparent state. In the mirror state, FIG. 4C shows, for example, a case where the two pixel positions in the center row in FIG. 1C are in the transparent state and the remaining four pixel positions are in the mirror state among the six pixel positions.

In the first embodiment, the light emitted from the light source 80 is incident on the electrodeposition element from the side surface and travels in the element.

For example, a part of the light emitted from the light source 80 is incident on the lower substrate 30 (transparent substrate 31) and the side surface of the electrolytic solution 50, and enters the lower substrate 30 (transparent substrate 31), the electrolytic solution 50, and the electrolytic solution 50. , The process proceeds in the fine uneven film 60. Then, due to the uneven structure of the fine uneven film 60, the lower substrate 30 (transparent substrate 31) is reflected in the direction intersecting the in-plane direction, and the lower substrate 30 is emitted. The light emitted from the lower substrate 30 passes through the upper substrate 20 at the pixel position in the transparent state and is emitted as illumination light (see FIG. 4A and the like). The intensity of the illumination light is the strongest in the directions of the substrates 20 and 30 normals. The light incident on the side surface of the transparent substrate 31 and not reflected by the uneven structure is guided through the transparent substrate 31 by, for example, total internal reflection.

The light reflected by the uneven structure of the fine uneven film 60 and emitted from the lower substrate 30 may be reflected at the pixel position (silver thin film forming position) in the mirror state. In that case, for example, it is incident on the lower substrate 30 again, then is reflected by the concave-convex structure of the fine concave-convex film 60, passes through the pixel position in the transparent state, and is emitted from the upper substrate 20 side (FIG. See 4B and FIG. 4C).

The light may enter the metal film (reflection film) 23 or the reflection plate 70 of the upper substrate 20. In this case, the light is reflected by the metal film (reflecting film) 23 and the reflecting plate 70, and then incidents on, for example, the lower substrate 30. Finally, it is reflected by the concave-convex structure of the fine concave-convex film 60, passes through the transparent pixel position, and is emitted from the upper substrate 20 side (see FIGS. 4A to 4C).

In the lighting apparatus according to the first embodiment, the electrodeposition element has a plurality of pixels capable of independently switching between a transparent state and a mirror state, and the light reflected by the concave-convex structure of the fine concave-convex film 60 is, for example, It is emitted through the pixel position of the upper substrate 20. Therefore, in the lighting device according to the first embodiment, the light transmission state (transparent state and mirror state) of the positions of the plurality of pixels is controlled, and the desired pixel positions (in the embodiment, the fine concavo-convex film 60 and the reflector 70) are controlled. Light can be emitted (surface emission) from the pixel position on the substrate 20 side where is not arranged. That is, the illuminating device according to the first embodiment is an illuminating device capable of electrically selecting (controlling) a light emitting region. All or a part of the pixels of the electrodeposition element are made transparent, and light is emitted from the pixel positions in the transparent state. In the lighting device according to the first embodiment, the pixel position of the upper substrate 20 is the light emitting region.

In the lighting device according to the first embodiment, at least the transparent substrate 31 is included in the light guide portion. For example, a part of the light emitted from the light source 80 is incident on the transparent substrate 31 from the side surface to guide the inside of the transparent substrate 31. However, such light guidance is not performed on the upper substrate 20 (transparent substrate 21). Immediately after the light source 80 is emitted, the light traveling toward the upper substrate 20 (transparent substrate 21) is reflected and shielded by, for example, the metal film 23. The metal film 23 is an example of a structure that prevents the light emitted from the light source 80 from entering the upper substrate 20 (transparent substrate 21).

The lighting device according to the first embodiment is an edge-type backlight unit that guides the light emitted by the light source 80 into the electrodeposition element and emits it. For example, it can be used in a liquid crystal display device, and local dimming can be performed. Although it is an edge-type backlight unit, it can perform local dimming and realize a high-contrast display.

In the lighting device according to the first embodiment, for example, the light reflected by the transparent electrode 22 (pixel portion), the metal film (reflection film) 23, and the reflector 70 in the mirror state can be reused. Therefore, for example, when some pixels are mirrored and the remaining pixels are in a transparent state, the brightness of the light emitted from the pixel positions in the transparent state can be increased. Further, when the brightness of the emitted light is constant, the light emission brightness of the light source 80 can be lowered and the power consumption can be suppressed. Further, since the light emitted from the light source 80 is guided through the electrodeposition element and emitted, the thinness is remarkably realized. As described above, the illuminating device according to the first embodiment is a high quality illuminating device.

By increasing the number of pixels that can switch between the transparent state and the mirror state independently of each other, the light emission position can be controlled more finely. Further, the shape of the light emitting region can be changed by changing the shape of the pixels of the electrodeposition element.

5A to 5D show a case where the number of pixels of the electrodeposition element is increased. Pixels that can switch between the transparent state and the mirror state independently of each other are arranged in 8 rows and 8 columns. Pixels in the mirror state are shaded.

FIG. 5A shows a case where all pixel positions are in a transparent state. The aperture ratio is 100%. 5B to 5D show a case where some pixel positions are in a mirror state and the remaining pixel positions are in a transparent state. The aperture ratios in the light transmitting state shown in FIGS. 5B, 5C, and 5D are 75%, 50%, and 25%, respectively. If all the pixel positions are in the mirror state, the aperture ratio can be set to 0%. By using an illumination device provided with an electrodeposition element having a large number of pixels, the aperture position, aperture ratio, etc. can be changed more freely.

A method of manufacturing the lighting device according to the second embodiment will be described with reference to FIGS. 6A to 6D and FIG. The illuminating device according to the first embodiment is an illuminating device that emits illuminating light from the upper substrate 20 side, but in the illuminating device according to the second embodiment, the illuminating light is emitted from both the upper and lower substrate 20 and 30 sides. Is emitted. Further, in the lighting device according to the second embodiment, for example, the light emitted from the light source 80 is incident on both the transparent substrates 21 and 31 from the side surface to guide the inside of both the transparent substrates 21 and 31. Therefore, in the second embodiment, for example, the metal film 23 is not arranged.

FIG. 6A shows a schematic plan view of the upper substrate (segment substrate) 20 in the second embodiment. For example, on a transparent substrate 21 which is a glass substrate, six transparent electrodes (segment electrodes) 22 electrically separated from each other are formed of a transparent conductive material such as ITO. Each transparent electrode 22 has, for example, a rectangular shape having a length of 21,000 μm and a width of 14,000 μm, and the distance between the electrodes 22 adjacent to each other in the vertical and horizontal directions is 10 μm. Unlike the first embodiment, the metal film (reflection film) 23 is not formed.

FIG. 6B shows a schematic plan view of the lower substrate (common substrate) 30 in the second embodiment. For example, a transparent electrode (common electrode) 32 is formed on a transparent substrate 31 which is a glass substrate with a transparent conductive material such as ITO. In the second embodiment, for example, a rectangular ITO film having a length of 32,000 μm and a width of 47,000 μm is separated into two regions that are electrically independent of each other to form two transparent electrodes 32.

The patterns of the transparent electrodes 22 and 32 are not limited to these, and may be patterned to a smaller size, for example. Further, for example, an active element such as a TFT may be used for the portion of the transparent electrode 22 pattern.

The substrates 20 and 30 shown in FIGS. 6A and 6B are arranged so as to face each other to form a cell. The cell formation step is the same as that in the first embodiment.

6C and 6D show a schematic plan view and a cross-sectional view of the electrodeposition element (mirror device) used in the lighting device according to the second embodiment, respectively.

Compared with the electrodeposition element used in the lighting device according to the first embodiment, the shapes of all the pixels do not match, but in a plan view, the electrodes 22 are inside the region surrounded by the sealing material 40. It is similar in that six rectangular pixels are defined at positions where 32 overlaps.

Since the six transparent electrodes 22 are electrically separated (independent) from each other, for example, the four transparent electrodes 22 in the left column and the center column are on the negative voltage side, and the two transparent electrodes 22 in the right column are on the positive voltage side. By applying a DC voltage on the side, it is possible to control the formation and non-formation of the silver thin film for each pixel.

As an example, when a negative DC voltage is applied to one or more of the four transparent electrodes 22 in the left column and the center row with the lower substrate 30 (transparent electrode 32) grounded, the transparent electrode to which the voltage is applied is applied. A silver thin film is formed on the 22 (pixel portion), the position is in the mirror state, and the other positions are in the transparent state. Further, when a positive DC voltage is applied to one or more of the two transparent electrodes 22 in the right column with the lower substrate 30 (transparent electrode 32) grounded, the voltage faces the applied transparent electrode 22. A silver thin film is formed on the transparent electrode 32 (pixel portion) at the position, the position is in the mirror state, and the other positions are in the transparent state.

Unless a voltage is applied to all the six transparent electrodes 22, silver thin films are not formed on the upper and lower substrates 20 and 30, for example, the entire area within the arrangement region of the electrolytic solution 50 (in the region surrounded by the sealing material 40). Becomes transparent. In this way, the formation position of the silver thin film (reflection region) can be electrically controlled within the arrangement region of the electrolytic solution 50.

The electrodeposition element shown in FIGS. 6C and 6D electrically switches between a transparent state and a mirror state for each pixel by, for example, a DC voltage applied to the transparent electrodes 22 and 32, and makes all pixels transparent or all pixels. Can be in a mirror state, some pixels can be in a transparent state, and the remaining pixels can be in a mirror state. The electrodeposition element shown in FIGS. 6C and 6D is a mirror device capable of switching between a transparent state and a mirror state (reflection state), for example, by controlling the non-application-application of voltage for each pixel.

See FIG. 7. By adding the fine concavo-convex film 60, the reflector (reflection member) 70, and the light source 80 to the electrodeposition elements shown in FIGS. 6C and 6D, the lighting device according to the second embodiment is manufactured. The fine concavo-convex film 60, the reflector 70, and the light source 80 are, for example, the same as those used in the first embodiment.

In the first embodiment, for example, the six pixel positions on the upper substrate 20 side are selective light emission positions by switching between the transparent state and the mirror state. On the other hand, in the second embodiment, for the four pixels in the left column and the center column, the pixel position on the upper substrate 20 side is the selective light emission position, and for the two pixels in the right column, the lower The pixel position on the side substrate 30 side is the selective light emission position.

Therefore, the fine concavo-convex film 60 is arranged at the pixel positions in the left and center rows on the lower surface (the surface opposite to the electrolytic solution 50) of the lower substrate 30 (transparent substrate 31), including the pixel positions as an example. Will be done. Further, the pixel positions in the right column on the upper surface (the surface opposite to the electrolytic solution 50) of the upper substrate 20 (transparent substrate 21) include the pixel positions as an example.

The reflector 70 is arranged at the pixel position of the substrate on which light is not emitted, and is not arranged at the pixel position of the substrate on which light is emitted. For example, the reflector 70 is located at four pixel positions in the left row and the center row on the upper surface of the upper substrate 20 (transparent substrate 21) and two pixel positions in the right row on the lower surface of the lower substrate 30 (transparent substrate 31). Is not placed. In the example shown in this figure, the reflector 70 is arranged around the electrodeposition element except for the pixel position on the substrate side, which is a selective light emitting region. Further, in relation to the fine concavo-convex film 60, the reflector 70 is arranged on the outside of the fine concavo-convex film 60 so as to cover, for example, the fine concavo-convex film 60. Further, the reflector 70 defines a space on one side (left side in FIG. 6C) side (upper side, lower side substrates 20 and 30, and outside of the sealing material 40) of the electrodeposition element.

The light source 80 is arranged in a space (side surface of the electrodeposition element) defined on one side of the electrodeposition element. The reflector 70 is arranged around the light source 80, which is not on the electrodeposition element side.

8A-8D schematically show the progress of the light emitted from the light source 80. In FIG. 8A, for example, when all six pixel positions are in a transparent state, in FIG. 8B, for example, among the six pixel positions, four pixel positions in the right column and the center column in FIG. 6C are in a transparent state, and the left column. When the two pixel positions are in the mirror state, for example, in FIG. 8C, of the six pixels, the four pixel positions in the left column and the right column in FIG. 6C are in the transparent state, and the two pixel positions in the center column are in the mirror state. In the case of FIG. 8D, for example, of the six pixel positions, the two pixel positions in the right column in FIG. 6C are in the transparent state, and the four pixel positions in the left column and the center column are in the mirror state.

Also in the second embodiment, as in the first embodiment, the light emitted from the light source 80 is incident on the electrodeposition element from the side surface and travels in the element. In the lighting device according to the first embodiment, the light emitted from the light source 80 does not guide the inside of the upper substrate 20 (transparent substrate 21), for example, in the lower substrate 30 (transparent substrate 31), in the electrolytic solution 50, and in the electrolytic solution 50. In the second embodiment, the light emitted from the light source 80 is, for example, the upper substrate 20 (transparent substrate 21), the lower substrate 30 (transparent substrate 31), and electrolysis. It is incident on these from the side surface of the liquid 50 and travels in the upper substrate 20 (transparent substrate 21), the lower substrate 30 (transparent substrate 31), the electrolytic solution 50, and the fine concavo-convex film 60. That is, for example, the entire electrodeposition element is a light guide portion. Then, the light is reflected in the direction intersecting the in-plane direction of the upper substrate 20 (transparent substrate 21) and the lower substrate 30 (transparent substrate 31) by the concave-convex structure of the fine concave-convex film 60, and the upper substrate 20 and the lower substrate 30 are reflected. Is emitted. The light emitted from the upper substrate 20 and the lower substrate 30 passes through the lower substrate 30 and the upper substrate 20 at the pixel positions in the transparent state and is emitted as illumination light (see FIG. 8A and the like). The intensity of the illumination light is the strongest in the directions of the substrates 20 and 30 normals. For example, the light incident on the side surfaces of the transparent substrates 21 and 31 and not reflected by the uneven structure is totally reflected to guide the inside of the transparent substrates 21 and 31.

For example, the light reflected by the uneven structure of the fine uneven film 60 and emitted from the upper substrate 20 and the lower substrate 30 may be reflected at the pixel position in the mirror state. In that case, for example, the upper substrate 20 and the lower substrate 30 are incident again, and then the upper and lower substrates 20 are reflected by the concave-convex structure of the fine concave-convex film 60 and transmitted through the transparent pixel positions. , 30 (see FIGS. 8B to 8D).

For example, the light guided through the upper substrate 20 (transparent substrate 21) may be finally emitted from the upper substrate 20 side, or the light guided through the lower substrate 30 (transparent substrate 31) is guided. Light may eventually be emitted from the lower substrate 30 side (see FIGS. 8C and 8D).

The light may enter the reflector 70. In this case, the light is reflected by the reflector 70 and enters the inside of the electrodeposition element. Finally, it is reflected by the concavo-convex structure of the fine concavo-convex film 60, passes through the pixel positions in the transparent state, and is emitted as illumination light (see FIGS. 8A to 8D).

Also in the lighting device according to the second embodiment, the electrodeposition element has a plurality of pixels capable of independently switching between the transparent state and the mirror state, and the light reflected by the concave-convex structure of the fine concave-convex film 60 is emitted. For example, it is emitted through the pixel position of the upper substrate 20 or the lower substrate 30. Therefore, also in the lighting device according to the second embodiment, the light transmission state (transparent state and mirror state) of the positions of the plurality of pixels is controlled, and the desired pixel positions (in the embodiment, the fine concavo-convex film 60 and the reflector 70) are controlled. Light can be emitted (surface emission) from the pixels positions on the substrates 20 and 30 on which the above is not arranged. In the lighting device according to the second embodiment, the pixel positions on the substrates 20 and 30 on which the fine concavo-convex film 60 and the reflector 70 are not arranged are light emission regions. The lighting device according to the second embodiment is also a lighting device capable of electrically selecting (controlling) the light emitting region, and all or a part of the pixels of the electrodeposition element is made transparent, and the light emitting region is made transparent. Illumination light is emitted from the pixel position.

The lighting device according to the second embodiment is also an edge-type backlight unit that guides the light emitted by the light source 80 into the electrodeposition element and emits it. For example, it is used for a liquid crystal display device for local dimming. It can be performed.

The lighting device according to the second embodiment can exhibit the same effect as that according to the first embodiment. Further, according to the lighting device according to the second embodiment, the illumination light can be emitted from both the substrates 20 and 30 sides, and the emission surface can be switched. The lighting device according to the second embodiment is also a high quality lighting device.

A first modification is shown in FIGS. 9A and 9B.

As shown in FIG. 9A, protrusions may be provided on the side surfaces of the transparent substrates 21 and 31 of the lighting device according to the embodiment on the light source 80 side (the surface on which the light emitted by the light source 80 is incident). In the case of the first embodiment (see FIG. 2), protrusions are provided on the transparent substrate 31, and in the case of the second embodiment (see FIG. 7), protrusions are provided on at least one of the transparent substrates 21 and 31, preferably both. .. The protrusions can emit the light source 80 to parallelize the light incident from the side surfaces of the transparent substrates 21 and 31, and guide the inside of the transparent substrates 21 and 31.

As shown in FIG. 9B, for example, protrusions may be provided on the side surface of the seal pattern 40 (the surface on which the light emitted by the light source 80 is incident) arranged along the side surface of the transparent substrate 31 on the light source 80 side. The light incident on the electrolytic solution 50 can be parallelized.

The protrusions shown in FIGS. 9A and 9B are arranged so as to face the region between the light sources (point light sources) which are LED elements, for example.

A second modification is shown in FIGS. 10A and 10B. The side surface of the transparent substrates 21 and 31 of the lighting device according to the embodiment on the light source 80 side (the surface on which the light emitted by the light source 80 is incident) is configured to have a larger area than the parallel cross section in the inner region of the main seal pattern 40, for example. You may.

As shown in FIG. 10A, in the case of the first embodiment, the side surface of the transparent substrate 31 on the light source 80 side, and in the case of the second embodiment, of the transparent substrates 21 and 31 as shown in FIG. 10B. The side surface of at least one of the above on the light source 80 side is configured to have a larger area than the parallel cross section in the arrangement region of the electrolytic solution 50, for example. In addition, FIG. 10B shows an example in which the side surface of both the transparent substrates 21 and 31 on the light source 80 side is configured to have a larger area than the cross section parallel to those of the substrates 21 and 31 in the arrangement region of the electrolytic solution 50. ..

With such a configuration, the light emitted from the light source 80 is likely to be incident from the side surfaces of the transparent substrates 21 and 31 (increase in the amount of light taken in), the amount of light guiding the inside of the transparent substrates 21 and 31 is large, and the electrolytic solution layer. The amount of light incident on 50 can be reduced. It is desirable that the cross-sectional shapes of the transparent substrates 21 and 31 change gently, for example, in the outer region of the main seal pattern 40.

For example, in a conventional edge type backlight, if the side surface of the light guide plate on the light source side is formed into a large area by gently changing the cross-sectional shape, there arises a problem that the frame becomes thick, but the illumination according to the second modification. In the device, such a problem does not occur.

FIG. 11 shows a third modification. In the lighting device according to the embodiment, the thicknesses of the transparent substrate 21 and the transparent substrate 31 can be made different from each other. Shown in this figure is a modified example of the lighting device according to the second embodiment. In the third modification, if the thicknesses of the transparent substrate 21 and the transparent substrate 31 are different from each other according to the area ratio of the light emitting region between the upper substrate 20 (transparent substrate 21) and the lower substrate 30 (transparent substrate 31). Let me. In the second embodiment, the ratio of the area of the light emitting region on the upper substrate 20 side to the area of the light emitting region on the lower substrate 30 side is, for example, 2: 1. Therefore, in the third modification, as an example, it is transparent. The ratio of the thickness of the substrate 21 to the thickness of the transparent substrate 31 is set to 1: 2, and the brightness of the light emitted from the upper substrate 20 side and the brightness of the light emitted from the lower substrate 30 side are made uniform.

For example, by adopting a light capture structure as described with reference to FIG. 10B and adjusting the area of the side surfaces of the transparent substrates 21 and 31 on the light source 80 side, the light emitted from both substrates 20 and 30 can be adjusted. It is also possible to make the brightness uniform.

FIG. 12A is a schematic perspective view showing the liquid crystal display device according to the third embodiment. The liquid crystal display device according to the third embodiment includes a liquid crystal display element 100, a lighting device 200, and a control device 300.

FIG. 12B shows a schematic cross-sectional view of the liquid crystal display element 100. As the liquid crystal display element 100, various known liquid crystal display elements can be used. This figure shows an example.

The liquid crystal display element 100 includes a liquid crystal cell 110 and polarizing plates 160 and 170 arranged on the upper and lower surfaces of the liquid crystal cell 11. The polarizing plates 160 and 170 are arranged on, for example, Cross Nicol.

The liquid crystal cell 110 includes an upper substrate 120 and a lower substrate 130 which are arranged so as to face each other substantially in parallel, and a liquid crystal layer 150 which is arranged between the two substrates 120 and 130.

The upper substrate 120 was formed on the transparent substrate 121, the transparent electrode 122 formed on the transparent substrate 121, the insulating film 123 formed on the transparent substrate 121 so as to cover the transparent electrode 122, and the insulating film 123. The alignment film 124 is provided.

Similarly, the lower substrate 130 is on the transparent substrate 131, the transparent electrode 132 formed on the transparent substrate 131, the insulating film 133 formed on the transparent substrate 131 so as to cover the transparent electrode 132, and the insulating film 133. The alignment film 134 formed on the surface is provided.

The transparent substrates 121 and 131 are, for example, glass substrates, the transparent electrodes 122 and 132 are, for example, ITO electrodes, and the insulating films 123 and 133 are, for example, SiO ₂ films. The alignment films 124 and 134 are formed by using a vertically alignment film material such as polyimide. The alignment films 124 and 134 are subjected to, for example, anti-parallel rubbing treatment.

The liquid crystal layer 150 is a vertically oriented liquid crystal layer formed by using a liquid crystal material having a negative dielectric anisotropy.

A display unit (pixel) for displaying is defined at a position where the electrodes 122 and 132 overlap in the arrangement region of the liquid crystal layer 150 in a plan view (when viewed from the normal direction of the substrates 120 and 130).

For example, a voltage is applied between the transparent electrodes 122 and 132 to change the liquid crystal molecular orientation state of the liquid crystal layer 150 for each display unit, and the liquid crystal cell 110 is driven to display a character. The liquid crystal display element 100 is, for example, a normally black type liquid crystal display element having a plurality of display units capable of independently switching between a light-transmitting state and a light-shielding state. A liquid crystal display element having a single display unit may be used.

The illumination device 200 is arranged so as to be laminated on the surface of the polarizing plate 170 opposite to the liquid crystal cell 110 (directly below the liquid crystal display element 100). The lighting device 200 emits illumination light toward the liquid crystal display element 100. (The illumination light of the illumination device 200 is incident on the liquid crystal cell 110.) The display surface of the liquid crystal display element 100 is a surface opposite to the illumination device 200.

As the illuminating device 200, for example, the illuminating device according to the first embodiment can be used. Here, the lighting device is provided with an electrodeposition element having a large number of pixels (see FIGS. 5A to 5D). It differs from the lighting device according to the first embodiment in that pixels capable of switching between a transparent state and a mirror state independently of each other are arranged in 8 rows and 8 columns.

FIG. 12C shows a schematic cross-sectional view of the lighting device 200. For example, in the lighting device according to the first embodiment, the rectangular transparent electrodes 22 are formed in 2 rows and 3 columns (see FIG. 1A), and these are formed in a small size rectangular shape in 8 rows and 8 columns. , The lighting device 200 can be manufactured.

The control device 300 controls the light transmission state (transparent state and mirror state) of a plurality of pixels (pixels arranged in 8 rows and 8 columns) of the lighting device 200, so that the emission region of the illumination light is set in pixel units. Control. Further, the liquid crystal molecular orientation state of the liquid crystal layer 150 of the liquid crystal display element 100 is changed for each display unit, for example, and the light transmission state (translucency state and light shielding state) of each display unit is controlled (driving the liquid crystal cell 110). ). Further, it controls to synchronize the emission region of the illumination light of the illumination device 200 with the drive of the liquid crystal cell 110.

For example, one or more display units of the liquid crystal display element 100 are set to be in a translucent state, and illumination light incident on the display unit in a translucent state is emitted at a position corresponding to the display unit in the translucent state. The pixel position of the lighting device 200 is set to the transparent state, and the other pixel positions are set to the mirror state. Specifically, the illumination light is emitted from the pixel position directly below the display unit that is in the translucent state (single or multiple pixel positions that include the display unit that is in the translucent state in plan view). Illumination light is not emitted from other pixel positions. In this way, the light emitting region of the lighting device 200 is controlled according to the display of the liquid crystal display element 100 (the liquid crystal molecular orientation state of the liquid crystal layer 150). By performing such control (local dimming), for example, high-quality display with high contrast can be performed.

The control device 300 may control the emission brightness of the light source 80 of the lighting device 200. Further, the drive of the liquid crystal cell 110 may be controlled to synchronize the light emission of the light source 80. For example, the emission brightness of the light source 80 is controlled according to the area of the pixels (aperture ratio of the lighting device 200) that is made transparent according to the display of the liquid crystal display element 100 (the liquid crystal molecular orientation state of the liquid crystal layer 150). As an example, the light emission of the light source 80 is controlled so that the brightness of the illumination light emitted toward the liquid crystal display element 100 is constant. With such control, it is possible to perform higher quality display.

Further, by changing the emission brightness of the light source 80 according to the drive of the liquid crystal cell 110 (aperture ratio of the lighting device 200), it is possible to reduce the power consumption of the liquid crystal display device according to the third embodiment. According to the results of diligent research by the inventors of the present application, it is the same as the case where the electrodeposition element is not driven and the illumination light having a constant brightness is emitted from the entire irradiation surface and the case where the electrodeposition element is driven. Comparing with the case of emitting bright illumination light, it is known that the power consumption can be reduced in the latter case even if the power required for driving the electrodeposition element is taken into consideration.

Further, the liquid crystal display device according to the third embodiment is a thin liquid crystal display device because it uses a lighting device 200 that guides the inside of the electrodeposition element.

As described above, the liquid crystal display device according to the third embodiment is a high quality liquid crystal display device.

Since the power consumption of the lighting device 200 and the power consumption of the liquid crystal display device according to the third embodiment also depend on the performance of the electrodeposition element (light transmittance, reflectance, etc.), for example, light in a transparent state. It is desirable to configure the illuminating device 200 by using an electrodeposition element having high transmittance and high reflectance in the mirror state.

Further, in the liquid crystal display device according to the third embodiment, the pixels of the lighting device 200 are formed in a rectangular shape and arranged in 8 rows and 8 columns, but the pixels of the lighting device 200 are displayed in a display unit (in which the emitted light is incident). The shape corresponding to the shape of the display unit of the liquid crystal display element 100) may be formed, for example, the same shape as the shape of the display unit, or a shape slightly offset outward from the contour of the display unit. The liquid crystal display element 100 and the lighting device 200 are arranged so that the pixels (light emitting region of the lighting device 200) formed in a shape corresponding to the shape of the display unit of the liquid crystal display element 100 are located, for example, directly below the display unit. Deploy.

Further, it is also possible to perform halftone display on the liquid crystal display element 100 and control the transparent state and the mirror state in the electrodeposition element of the lighting device 200 to the intermediate state. The intermediate state means a state in which the Ag film is not formed on the entire surface and the Ag nucleus is partially formed. In the intermediate state, the reflectance and the light transmittance are intermediate values between the mirror state in which Ag is attached to the entire surface and the transparent state. An intermediate state can be realized by intermittently applying a drive voltage (see, for example, Japanese Patent Application Laid-Open No. 2015-082081). The degree of reflectance and light transmittance can be controlled, for example, by the applied voltage waveform.

By using the intermediate state, it is possible to efficiently obtain the effect of further improving the appearance and suppressing the power consumption. For example, if the light transmittance of the electrodeposition element is set to 0% when the image of a certain area is darkened, it cannot be visually recognized as a display. Therefore, by using the intermediate state, it is possible to control according to the brightness of the liquid crystal display element. Display performance can be improved by such control, and further, low power consumption can be realized.

FIG. 13A is a schematic perspective view showing a liquid crystal display device according to a fourth embodiment. The liquid crystal display device according to the fourth embodiment includes liquid crystal display elements 400f and 400r, a lighting device 500, and a control device 600.

FIG. 13B shows an example of the arrangement mode of the liquid crystal display elements 400f, 400r, and the lighting device 500.

As the illuminating device 500, for example, the illuminating device according to the second embodiment is used.

As the liquid crystal display elements 400f and 400r, various known liquid crystal display elements can be used. For example, a liquid crystal display element having the same structure as the liquid crystal display element 100 shown in FIG. 12B is used. Also in the liquid crystal display elements 400f and 400r, the display unit (pixel) is defined at a position where the electrodes overlap in the arrangement region of the liquid crystal layer in a plan view. The liquid crystal display elements 400f and 400r are also normally black type liquid crystal display elements having a plurality of display units capable of independently switching between a light transmissive state and a light blocking state, for example. A liquid crystal display element having a single display unit may be used.

The liquid crystal display element 400f is laminated and arranged on the upper substrate 20 side (immediately above the lighting device 500) of the lighting device 500. Further, the liquid crystal display element 400f is arranged so that the display unit is located directly above the light emitting region on the upper substrate 20 side of the lighting device 500.

The liquid crystal display element 400r is laminated and arranged on the lower substrate 30 side (directly below the lighting device 500) of the lighting device 500. Further, the liquid crystal display element 400r is arranged so that the display unit is located directly below the light emitting region on the lower substrate 30 side of the lighting device 500.

The lighting device 500 emits illumination light toward the liquid crystal display elements 400f and 400r. The display surfaces of the liquid crystal display elements 400f and 400r are surfaces opposite to the lighting device 500.

The control device 600 controls the emission region of the illumination light on a pixel-by-pixel basis by controlling the light transmission states (transparent state and mirror state) of the six pixel positions of the illumination device 500. Further, the liquid crystal molecular orientation state of the liquid crystal layers of the liquid crystal display elements 400f and 400r is changed for each display unit, for example, and the light transmission state (translucency state and light shielding state) of each display unit is controlled (liquid crystal display element 400f). , 400r liquid crystal cell is driven, respectively). Further, control is performed so that the emission region of the illumination light of the illumination device 500 is synchronized with the drive of the liquid crystal cells of the liquid crystal display elements 400f and 400r.

For example, among all the display units of the liquid crystal display elements 400f and 400r, one or a plurality of display units are set to the translucent state, and the positions corresponding to the translucent display units (the translucent state is set). The pixel position of the lighting device 500 (which emits the illumination light incident on the display unit) is set to the transparent state, and the other pixel positions are set to the mirror state. Specifically, the illumination light is emitted from the pixel position directly below or directly above the display unit in the translucent state (single or multiple pixel positions that include the display unit in the translucent state in plan view). Is emitted, and illumination light is not emitted from other pixel positions. In this way, the light emitting region of the lighting device 500 is controlled according to the display of the liquid crystal display elements 400f and 400r (the liquid crystal molecular orientation state of the liquid crystal layer of the liquid crystal display elements 400f and 400r). By performing such control (local dimming), for example, high-quality display with high contrast can be performed. The liquid crystal display device according to the fourth embodiment is a liquid crystal display device that partially drives two liquid crystal display elements 400f and 400r using one lighting device 500.

The control device 600 may control the emission brightness of the light source 80 of the lighting device 500. Further, control may be performed to synchronize the driving of the liquid crystal cells of the liquid crystal display elements 400f and 400r with the light emission of the light source 80. For example, the light source 80 is made transparent according to the display of the liquid crystal display elements 400f and 400r (the liquid crystal molecular orientation state of the liquid crystal layer of the liquid crystal display elements 400f and 400r) according to the area of the pixel (aperture ratio of the lighting device 500). Controls the emission brightness of. As an example, the light emission of the light source 80 is controlled so that the illumination light having a constant brightness is emitted toward the liquid crystal display elements 400f and 400r. With such control, it is possible to perform higher quality display.

Further, by changing the emission brightness of the light source 80 according to the drive of the liquid crystal cells of the liquid crystal display elements 400f and 400r (aperture ratio of the lighting device 500), it is possible to reduce the power consumption of the liquid crystal display device according to the fourth embodiment. Is.

Further, the liquid crystal display device according to the fourth embodiment is also a thin liquid crystal display device because it uses the lighting device 500 that guides the inside of the electrodeposition element.

In addition, in the liquid crystal display device according to the fourth embodiment, the liquid crystal display elements 400f and 400r arranged on the substrates 20 and 30 of the lighting device 500 are simultaneously driven, and double-sided display is performed using one lighting device 500. It can be performed.

The liquid crystal display device according to the fourth embodiment is also a high quality liquid crystal display device.

In the liquid crystal display device according to the fourth embodiment, as in the third embodiment, in order to reduce power consumption, for example, an electrodeposition element having high light transmittance in the transparent state and high reflectance in the mirror state is used. Therefore, it is desirable to configure the lighting device 500.

Further, the pixels of the lighting device 500 may be formed in a shape corresponding to the shape of the display unit (display unit of the liquid crystal display elements 400f and 400r) on which the emitted light is incident, and the liquid crystal display elements 400f and 400r are intermediate. Similar to the case of the third embodiment, the adjustment display may be performed and the transparent state and the mirror state of the electrodeposition element of the lighting device 500 may be controlled to the intermediate state.

FIG. 14A is a schematic perspective view showing a liquid crystal display device according to a fifth embodiment. The liquid crystal display device according to the fifth embodiment includes a liquid crystal display element 180, a lighting device 700, an electrodeposition element 800, and a control device 900. The electrodeposition element 800 is laminated and arranged on the upper surface of the lighting device 700, and the liquid crystal display element 180 is laminated and arranged on the upper surface of the electrodeposition element 800.

See FIG. 14B. The illuminating device 700 is, for example, a known edge type backlight, and includes a light source 710 and a light guide plate 720.

The electrodeposition element 800 has a configuration in which the metal film (reflection film) 23 is removed from the electrodeposition element used in the lighting device 200 shown in FIG. 12C, for example. The electrodeposition element 800 includes pixels arranged in 8 rows and 8 columns, which can switch between a transparent state and a mirror state independently of each other. In this figure, the pixels in the mirror state are shaded.

As the liquid crystal display element 180, various known liquid crystal display elements can be used. For example, a liquid crystal display element having the same structure as the liquid crystal display element 100 shown in FIG. 12B is used. Also in the liquid crystal display element 180, the display unit (pixel) is defined at a position where the electrodes overlap in the arrangement region of the liquid crystal layer in a plan view. The liquid crystal display element 180 is also a normally black type liquid crystal display element having a plurality of display units capable of switching between a light transmitting state and a light blocking state independently of each other, for example. A liquid crystal display element having a single display unit may be used.

The lighting device 700, the electrodeposition element 800, and the liquid crystal display element 180 include, for example, a light guide plate 720 portion of the lighting device 700, a pixel arrangement area (illumination light emission area) of the electrodeposition element 800, and a liquid crystal display element. The 180 display areas (arrangement areas of the display units) are stacked so as to overlap each other. For example, the polarizing plate 170 (see FIG. 12B) of the liquid crystal display element 180 is arranged on the upper surface of the electrodeposition element 800.

FIG. 14C shows a schematic cross-sectional view of the lighting device 700. The lighting device 700 includes a light source 710, a light guide plate 720, a light source cover 730, and reflection dots 740.

The light source 710 is, for example, a linear LED light source or CCFL. The light guide plate 720 is made of, for example, acrylic. The light source cover 730 is made of, for example, a high reflectance material and is arranged around the light source 710. The reflective dots 740 are formed of, for example, white ink.

The illuminating device 700 emits illuminating light toward the electrodeposition element 800. Specifically, the light emitted from the light source 710 is directly reflected by the light source cover 730, enters the light source from the side surface of the light guide plate 720, and travels in the light guide plate 720. Then, it is reflected by the reflection dots 740, emits the light guide plate 720, and is incident on the electrodeposition element 800.

FIG. 14D schematically shows the progress of the light reflected by the reflection dots 740. The light reflected by the reflection dots 740 and emitted from the light guide plate 720 and incident on the electrodeposition element 800 passes through the transparent pixel positions of the electrodeposition element 800 and is incident on the liquid crystal display element 180. .. The light emitted from the light guide plate 720 and incident on the pixel position of the electrodeposition element 800 in the reflected state is reflected and re-entered on the light guide plate 720 of the lighting device 700, and finally reflected by the reflection dots 740. Then, it passes through the transparent pixel position of the electrodeposition element 800 and is incident on the liquid crystal display element 180. The liquid crystal display element 180 is displayed by using the light incident on the liquid crystal display element 180.

The control device 900 controls the light transmission state (transparent state and mirror state) of a plurality of pixels (pixels arranged in 8 rows and 8 columns) of the electrodeposition element 800 so that the light is incident on the liquid crystal display element 180. The light emission region is controlled on a pixel-by-pixel basis. Further, the liquid crystal molecular orientation state of the liquid crystal layer of the liquid crystal display element 180 is changed for each display unit, for example, and the light transmission state (translucent state and light blocking state) of each display unit is controlled (the liquid crystal cell of the liquid crystal display element 180). To drive). Further, control is performed so that the light emitting region emitted from the electrodeposition element 800 is synchronized with the driving of the liquid crystal cell of the liquid crystal display element 180.

For example, one or more display units of the liquid crystal display element 180 are set to the translucent state, and light incident on the display unit in the translucent state is emitted at a position corresponding to the display unit in the translucent state. ) The pixel position of the electrodeposition element 800 is set to the transparent state, and the other pixel positions are set to the mirror state. Specifically, light is emitted from a pixel position directly below the display unit in the translucent state (a single or multiple pixel positions that include the display unit in the translucent state in a plan view), and the like. No light is emitted from the pixel position of. In this way, the light emitting region of the electrodeposition element 800 is controlled according to the display of the liquid crystal display element 180 (the liquid crystal molecular orientation state of the liquid crystal layer of the liquid crystal display element 180). By performing such control (local dimming), for example, high-quality display with high contrast can be performed.

The control device 900 may control the emission brightness of the light source 710 of the lighting device 700. Further, control may be performed to synchronize the drive of the liquid crystal cell of the liquid crystal display element 180 with the light emission of the light source 710 of the lighting device 700. For example, the area of the pixels of the electrodeposition element 800 (aperture ratio of the electrodeposition element 800), which is made transparent according to the display of the liquid crystal display element 180 (the liquid crystal molecular orientation state of the liquid crystal layer of the liquid crystal display element 180). The emission brightness of the light source 710 of the lighting device 700 is controlled accordingly. As an example, the light emission of the light source 710 of the lighting device 700 is controlled so that the brightness of the light emitted from the electrodeposition element 800 toward the liquid crystal display element 180 is constant. With such control, it is possible to perform higher quality display.

Further, by changing the emission brightness of the light source 710 of the lighting device 700 according to the drive of the liquid crystal cell of the liquid crystal display element 180 (aperture ratio of the electrodeposition element 800), the consumption of the liquid crystal display device according to the fifth embodiment is low. It is also possible to use electricity.

Further, since the lighting device 700, the electrodeposition element 800, and the liquid crystal display element 180 are laminated and arranged, the liquid crystal display device according to the fifth embodiment can also be made thinner.

As described above, the liquid crystal display device according to the fifth embodiment is a high quality liquid crystal display device.

Similar to the liquid crystal display devices according to the third and fourth embodiments, it is desirable to use the electrodeposition element 800 having high light transmittance in the transparent state and high reflectance in the mirror state, for example, in order to reduce power consumption. ..

Further, the pixels of the electrodeposition element 800 may be formed in a shape corresponding to the shape of the display unit (display unit of the liquid crystal display element 180) on which the emitted light is incident, and the liquid crystal display element 180 displays halftones. The same applies to the third and fourth embodiments, in that the transparent state and the mirror state of the electrodeposition element 800 may be controlled to intermediate states.

Further, in the liquid crystal display device according to the fifth embodiment, the lighting device 700 that emits light from one side is used, and the electrodeposition element 800 and the liquid crystal display element 180 are laminated and arranged on one side (light emitting surface) of the lighting device 700. An electrodeposition element and a liquid crystal display element may be laminated and arranged on both sides of the lighting device.

Although the present invention has been described above with reference to Examples and Modifications, the present invention is not limited thereto.

In the lighting apparatus according to the examples and modifications, for example, the fine concavo-convex film 60 is arranged on the substrates 20 and 30 as a light extraction structure for emitting light propagating in the electrodeposition element as illumination light, but light scattering A board or the like may be arranged. Further, a fine uneven structure may be formed on the surface of the substrates 20 and 30 (transparent substrates 21 and 31) opposite to the electrolytic solution 50 by, for example, roughening with blasting or the like. It is also possible to form a fine concavo-convex structure on the surface of the transparent substrates 21 and 31 on the electrolytic solution 50 side. These are all examples of substrates 20 and 30 having a fine concavo-convex structure (light extraction structure).

Further, in the lighting device according to the embodiment and the modified example, the fine concavo-convex film 60 is arranged on the substrates 30 and 20 facing the substrates 20 and 30 that emit the illumination light for each pixel position, specifically, the substrate 30. Although it is arranged including 20 pixel positions, it is also possible to arrange it in a part of the pixel positions instead of all of them.

For example, in the lighting device according to the second embodiment, the illumination light is emitted from only one pixel position to only one side of the substrates 20 and 30, but the substrates 20 and 30 are emitted from one pixel position. The illumination light may be emitted to both sides of the above. In this case, for example, the fine concavo-convex film 60 is arranged on the outside of both the transparent substrates 21 and 31 at the pixel positions, and the reflector 70 is not arranged. With such a configuration, control may be performed so that the illumination light is not emitted from both the substrates 21 and 31 at the same time, or control is performed so that the illumination light is emitted from both the substrates 21 and 31 at the same time. You may go.

In the liquid crystal display device according to the fourth embodiment, since the lighting device according to the second embodiment is used as the lighting device 500, the liquid crystal display in which the display units (display units that actually perform the display) do not overlap each other in a plan view. Elements 400f and 400r are adopted. If the lighting device 500 is a lighting device capable of emitting illumination light from one pixel position to both sides of the substrates 20 and 30, a liquid crystal display element in which the positions of display units that actually perform display overlap in a plan view. Can be used. In addition, the variety of display can be improved.

In the lighting device according to the embodiment and the modification, the transparent state and the mirror state of all the pixels of the electrodeposition element can be switched independently of each other, but the light transmission states of some pixels can also be matched. .. Any electrodeposition element containing a plurality of pixels capable of switching between a transparent state and a mirror state independently of each other may be used.

Further, in the lighting apparatus according to the examples and modifications, the transparent electrodes 22 and 32 are used as patterning electrodes, and silver is deposited on the patterning electrodes. For example, the insulating film is patterned on the solid electrode and the non-forming position of the insulating film is formed. Silver may be deposited at (exposed position of the electrode, for example, an opening). The insulating film can be configured to be included in at least one of the substrates 20 and 30.

Further, in the lighting device according to the embodiment and the modification, the sealing material 40 which is transparent to the light emitted from the light source 80, for example, transparent to the visible light is used, but for the light emitted from the light source 80. An opaque sealing material can also be used.

Further, in the lighting device according to the embodiment and the modified example, the light source 80 is arranged on one side surface of the electrodeposition element, for example, but it may be arranged on a plurality of side surfaces.

Further, in the lighting apparatus according to the examples and modifications, the bulk type electrodeposition element is used, but the interface type electrodeposition element can also be used.

Further, in the lighting device according to the first embodiment, in order to further suppress the light emitted from the light source 80 from entering the transparent substrate 21, black printing is performed on the electrode 22 and the metal film 23 non-formed region located near the light source 80. For example, the transparent substrate 21 may not be exposed on the light source 80 side.

Further, in the lighting device according to the second embodiment, the electrodes of the lower substrate 30 are two electrodes 32 that are electrically separated from each other, but the electrodes 32 do not have to be electrically separated.

Further, in the liquid crystal display device according to the fifth embodiment, the polarizing plate 170 is arranged between the liquid crystal cell of the liquid crystal display element 180 and the electrodeposition element 800. For example, the transparent substrate 131 of the liquid crystal cell of the liquid crystal display element 180 ( (See FIG. 12B) and the transparent substrate 21 on the upper side of the electrodeposition element 800 may be shared (same substrate), and the polarizing plate 170 may be arranged between the electrodeposition element 800 and the lighting device 700.

Further, in the liquid crystal display device according to the embodiment, the control device controls, for example, the drive of the liquid crystal cell and the emission region of the illumination light, and further controls the drive of the liquid crystal cell and the light emission of the light source. For example, the emission region of the illumination light may be controlled according to the brightness of the surroundings (usage environment) measured by the sensor, and the light emission of the light source may be controlled according to the brightness of the surroundings (usage environment). You may.

As an example, in an environment where external light is strong, such as directly under sunlight in the daytime, control is performed so that all pixel positions of the electrodeposition element are in a mirror state (control that does not form an emission region of illumination light), and is a reflection type. Used as a liquid crystal display device. Further, at this time, control is performed so that light is not emitted from, for example, a light source which is an LED element. Depending on the intensity (brightness) of the external light, some pixel positions may be in a mirror state and the remaining pixel positions may be in a transparent state.

On the other hand, in an environment where the outside light is weak, such as at night, the control as described in the embodiment is performed as a transmissive liquid crystal display device. By controlling the emission region of the illumination light and the light emission of the light source according to the ambient brightness, the power consumption can be further suppressed and good visibility can be ensured regardless of the usage environment.

Combinations of examples, modifications, etc. are also possible.

In addition, it will be obvious to those skilled in the art that various changes, improvements, combinations, etc. are possible. For example, the liquid crystal display element may be a TFT type.

The lighting device according to the embodiment and the modification is configured to include an electrodeposition element. Since the electrodeposition element does not have an air layer, it can be a lighting device having high energy efficiency and the like.

The lighting devices according to the examples and modifications can be used as various lighting devices including general lighting. It can be suitably used for products for which high contrast display, power saving, and thinning are desired, such as laptop computers, smartphones, mobile phones, and backlights used in various liquid crystal display devices. In particular, it is suitable for use in portable displays. It can also be used as a lighting device capable of displaying characters and images.

The lighting device according to the second embodiment can be used for a double-sided display. It can be suitably used for thin backlights such as mobile phones that switch between main display and sub display, notebook computers and smartphones that display both sides.

10a Upper substrate 10b Lower substrate 11a Upper transparent substrate 11b Lower transparent substrate 12a Upper transparent electrode 12b Lower transparent electrode 14 Sealing material 15 Electrolyte layer 20 Upper substrate 21 Transparent substrate 22 Transparent electrode 23 Metal film 30 Lower substrate 31 Transparent substrate 32 Transparent electrode 40 Sealing material 50 Electrolyte 60 Fine uneven film 70 Reflector 80 Light source 100 Liquid crystal display element 110 Liquid crystal cell 120 Upper substrate 121 Transparent substrate 122 Transparent electrode 123 Insulating film 124 Alignment film 130 Lower substrate 131 Transparent substrate 132 Transparent electrode 133 Insulating film 134 Alignment film 150 Liquid crystal layer 160, 170 Plate plate 180 Liquid crystal display element 200 Lighting device 300 Control device 400f, 400r Liquid crystal display element 500 Lighting device 600 Control device 700 Lighting device 710 Light source 720 Light guide plate 730 Light source cover 740 Reflective dots 800 Electrodeposition element 900 Control device

Claims (11)

Light source and
The light emitted from the light source is arranged at a position where it is incident from the side surface, and is arranged so as to (i) a first substrate having a first electrode and a light extraction structure and (ii) substantially parallel to the first substrate. A second substrate having two electrodes and (iii) an electrolyte layer arranged between the first substrate and the second substrate and containing a silver-containing electrodeposition material, incident from the side surface, and inside. It has an electrodeposition element that extracts the light traveling through the light as illumination light.
In the electrodeposition element,
When viewed from the normal direction of the first and second substrates, at the positions of the first pixel and the second pixel defined at the positions where the first electrode and the second electrode overlap in the arrangement region of the electrolyte layer. The transparent state and the mirror state can be switched independently of each other.
The light extraction structure is arranged at the positions of the first and second pixels of the first substrate.
The light traveling inside is an illumination device that is taken out as illumination light from the positions of the first and second pixels of the second substrate. The lighting device according to claim 1, wherein the electrodeposition element has a structure that prevents light emitted from the light source from entering the second substrate. The lighting device according to claim 2, wherein a reflective film is arranged on the second substrate as a structure for preventing the light emitted from the light source from entering the second substrate. The lighting device according to claim 2 or 3, wherein a protrusion that emits the light source and parallelizes the light incident from the side surface of the first substrate is formed on the side surface of the first substrate. The electrolyte layer is arranged in the inner region of the sealing material between the first substrate and the second substrate.
The claim that a protrusion that emits the light source and parallelizes the light incident from the side surface of the sealing material is formed on the side surface of the sealing material arranged along the side surface of the first substrate on the light source side. The lighting device according to any one of 2 to 4. The lighting device according to any one of claims 2 to 5, wherein the side surface of the first substrate on the light source side has a larger area than the parallel cross section in the arrangement region of the electrolyte layer. The electrodeposition element is arranged at a position where the light emitted from the light source is incident on both the side surface of the first substrate and the side surface of the second substrate.
In the electrodeposition element, the first electrode is defined at a position where the first electrode and the second electrode overlap in the arrangement region of the electrolyte layer when viewed from the normal direction of the first and second substrates. The transparent state and the mirror state at the positions of the 1 pixel, the 2nd pixel, and the 3rd pixel can be switched independently of each other, and the position of the 1st pixel or the 3rd pixel of the 2nd substrate can be switched. The light extraction structure is also placed at the position of
The lighting device according to claim 1, wherein the light traveling inside the electrodeposition element is also taken out as illumination light from the position of the first pixel or the position of the third pixel of the first substrate. Of the first substrate or the second substrate, the thickness of the substrate on the first substrate and the substrate having a smaller area ratio of the light emitting region on the second substrate is the substrate having a larger area ratio of the light emitting region. The lighting device according to claim 7, which is thicker than the thickness of the above. In addition
The illuminating device according to any one of claims 1 to 8, further comprising a reflecting member arranged around the electrodeposition element, reflecting incident light, and incident on the inside of the electrodeposition element. The lighting device according to any one of claims 1 to 9,
A liquid crystal cell arranged at a position where the illumination light emitted from the illumination device is incident, and
A liquid crystal display device including a control device that controls the drive of the liquid crystal cell and the synchronization of the emission region of the illumination light emitted from the lighting device. The liquid crystal display device according to claim 10, wherein the control device further controls the drive of the liquid crystal cell and the light emission of the light source of the lighting device.

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