JP2004184980A - Composite display system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a composite display system that is transparent and has an open feeling when it is not used, can simultaneously view display of a background and display of an electro-optical element during usage and can give an impression so that an image floats in a space. <P>SOLUTION: The composite display system arranging a second display body between a first display body 1 and an observer 3, transmits light when the second display body is impressed by voltage, and is made the electro-optical element 2 scattering light when voltage is impressed. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention relates to a composite display device in which display bodies are stacked, and more specifically, to a composite display device in which a display body disposed on an observer side can be visually recognized by using a transparent body.

  As a conventional example in which a display is stacked and a new display is performed, a first liquid crystal panel is disposed in front of a dial of a meter, and a light scattering state and a light transmitting state are provided between the dial and the first liquid crystal panel. There is a PDLC (polymer disperse liquid crystal) that can be switched between (see, for example, Patent Document 1). As a technique similar to the meter in the PDLC, there is a light control glass, which is in a light transmission state by applying a voltage, and in a light scattering state in a state in which no voltage is applied.

  In this conventional example, when the PDLC is in the light transmission state, the display content of the dial is visually recognized in addition to the display content of the first liquid crystal panel. When the PDLC is in the light scattering state, the information on the dial is visible. Instead, only the display content of the first liquid crystal panel is visually recognized. That is, the PDLC serves as a shielding plate for the dial.

  The PDLC is in a light transmission state by applying a voltage, and in a light scattering state when no voltage is applied. Therefore, the light scatterer is present when no voltage is applied, for example, when the power is turned off.

Japanese Patent Laid-Open No. 7-271310 (pages 2 to 4, FIGS. 1 and 2)

  When the power of the display device is on and the light transmission state and the light scattering state can be controlled by the presence or absence of the applied voltage, there is no problem even if PDLC is used as a shielding plate. It is desired to be a transparent body. For example, when a PDLC is placed in front of a vehicle instrument (instrument panel, etc.), there is a problem that the scale of the fuel gauge cannot be read and the odrip meter cannot be read unless the vehicle is turned on. .

  If the voltage is always applied to the PDLC, the problem that the instrument in the background cannot be read can be solved. However, the voltage applied to the PDLC is high, and due to the problem of power consumption, the voltage is not always applied in practice. could not.

  Accordingly, an object of the present invention is to provide a composite display body that is transparent when not in use, and whose presence itself is unobtrusive and does not give a feeling of pressure. Another object of the present invention is to provide a novel display using a transparent display body and a background display body.

  That is, according to the first aspect of the present invention, in the composite display device in which the second display body is disposed between the first display body and the observer, the second display body transmits light when no voltage is applied. A composite display device comprising an electro-optic element that scatters light when a voltage is applied.

  With such a configuration, the electro-optical element becomes transparent even when no voltage is not applied, and the display body disposed behind the electro-optical element can be visually recognized. Moreover, since it is a transparent body, it does not feel a sense of pressure due to its presence.

  Aspect 2 is the composite display device according to aspect 1, wherein the first display body is a meter. Aspect 3 is the composite display device according to aspect 1, wherein the first display body is a mirror. With such a configuration, a novel display such as a transparent display and a three-dimensional display can be performed in combination with an instrument or mirror behind.

  Aspect 4 is the composite display device according to aspect 1, in which a plurality of the second display bodies are arranged in a stacked manner. In the aspect 5, when the display patterns of the plurality of second display bodies are the same and one of the second display bodies is in the display state, the other second display body is in the non-display state. A composite display device according to a fourth aspect. With such a configuration, the display can be spatially moved on the second display body, and display that is three-dimensional and highly appealing to the viewer can be performed.

  Aspect 6 is a liquid crystal / cured resin in which the electro-optical element includes a liquid crystal layer sandwiched between a pair of substrates with transparent electrodes, and the liquid crystal layer includes a cured product of liquid crystal and a curable compound that is soluble in the liquid crystal. It is a composite display apparatus in any one of the aspects 1-5 which consist of composites.

  With such a configuration, the solubility with the liquid crystal is improved, alignment defects can be reduced, and the transparency of the electro-optic element is improved. Further, the alignment stability of the liquid crystal molecules is excellent, and the life of the composite display device is improved.

  According to the present invention, it is transparent when not in use, its presence itself is unobtrusive, does not give a feeling of pressure, has a feeling of openness, and when used, the display of the electro-optic element and the display behind (background) Can be displayed at the same time. Further, since the portions other than the display portion of the electro-optic element are transparent, it is possible to realize a display that gives an impression that an image or a message is floating in the space.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a conceptual diagram schematically showing the basic arrangement of the composite display device of the present invention. As shown in FIG. 1, an electro-optic element 2 as a second display body is disposed between the first display body 1 and the observer 3.

The electro-optical element 2 used in the present invention is one in which the liquid crystal layer sandwiched between the transparent substrates 21 and 22 can repeatedly take a light transmitting state and a light scattering state. The light transmission state and the light scattering state are states applied to visible light. As the light transmission state, when the electro-optic element 2 is not displaying, for example, when the power is turned off, the background side of the electro-optic element 2 can be seen, and the light transmittance is preferably high so as to give a sense of openness. The light transmittance is preferably 50% or more, particularly preferably 80% or more, but can be appropriately selected according to the required degree of openness and transparency. Moreover, there is no restriction | limiting in particular as a light-scattering state, However, For the purpose of shielding the display of the 1st display body 1, the one where a scattering property is higher is preferable. In particular, the haze value is preferably 80% or more. The haze value was measured with HGS-3DP manufactured by Suga Test Instruments Co., Ltd. The haze is defined in JIS R3212, 7105, and is given by haze value = (diffuse transmittance / total light transmittance) × 100 (%).
In the present invention, the first display body may be a landscape in a visual field direction that can be seen through the electro-optical element 2 installed in a driver's seat such as a train, an automobile, or an airplane. For example, in an automobile, the composite display device of the present invention is installed on a dashboard, and an observer can view the display of the electro-optic element and the visual field in the same visual field direction.
Further, the person or the person on the other side or the other person when the person exchanges necessary information or delivers the article is included as the first display body. It corresponds to the person in charge of service at the cash register, counter, and reception at banks, stations, supermarkets, department stores, convenience stores and the like.
The first display body 1 may be an object to be visually recognized by an observer. It may be a displayed product, a person who wants to provide services, or a ticket machine that provides tickets. In the present invention, the viewer can appropriately view the first display body and can display specific information on the second display body.
Furthermore, although depending on the incident direction of the light beam to the electro-optical element 2, when the electro-optical element 2 is disposed on the front surface of a vehicle speedometer or the like, the light beam from the speedometer or the like is used at night. A higher forward scattering rate is preferred.

  The switching between the light transmitting state and the light scattering state is performed by the electro-optic element 2 including a liquid crystal layer 27 and a transparent substrate with a pair of transparent electrodes that sandwich the liquid crystal layer 27, and a voltage is applied between the transparent electrodes 23 and 24. Can be realized by causing the liquid crystal layer 27 to be in a light-scattering state when the voltage is applied, and causing the liquid crystal layer 27 to be in a light-transmitting state when voltage application between the transparent electrodes 23 and 24 is stopped.

  As the liquid crystal layer 27, a liquid crystal / cured resin composite comprising a liquid crystal and a cured product of a curable compound soluble in the liquid crystal can be used. The liquid crystal layer 27 composed of a liquid crystal and a curable resin sandwiches a mixture containing a liquid crystal and a curable compound between a pair of transparent substrates with a transparent electrode, and uses a means such as heat, ultraviolet rays, or an electron beam to achieve this curable property. The compound can be cured to form a liquid crystal / cured resin composite layer.

  Such a cured resin may be any known resin as long as it has transparency and does not violate the gist of the present invention. It is particularly preferable to have a structure in which the cured resin is separated from the viewpoint of high-speed response and driving voltage reduction.

  By selecting a curable compound that can be dissolved in the liquid crystal, the alignment state of the mixture when uncured can be controlled, and high transparency can be obtained when the curable compound is cured.

  It is preferable to appropriately select the pretilt angle of the liquid crystal molecules depending on whether the liquid crystal has a positive or negative dielectric anisotropy. When the dielectric anisotropy is positive, the pretilt angle is preferably 30 ° or less with respect to the substrate surface, and when the dielectric anisotropy is negative, it is preferably 60 ° or more with respect to the substrate surface. By having a pretilt angle within these ranges, alignment defects can be reduced and transparency is improved. When the pretilt angle is 60 ° or more, the rubbing process may or may not be performed. The pretilt angle is more preferably 70 ° or more. The pretilt angle has a maximum value of 90 ° in a direction perpendicular to the substrate surface. That is, the pretilt angle does not become 100 °.

  Examples of the curable compound having high solubility with the liquid crystal include the compound of the formula (1) and the compound of the formula (2).

A ¹ —O— (R ¹ ) _m —O—Z—O— (R ² ) _n O—A ² Formula (1)
_{^{A 3 - (OR 3) o}} -O-Z'-O- (R 4 O) p -A 4 ··· formula (2)
Here, A ¹ , A ² , A ³ and A ⁴ are each independently an acryloyl group, a methacryloyl group, a glycidyl group or an allyl group, and R ¹ , R ² , R ³ and R ⁴ are each independently , An alkylene group having 2 to 12 carbon atoms, Z and Z ′ are each independently a divalent mesogen structure part, and m, n, o, and p are each independently an integer of 1 to 10. is there.

R ¹ , R ² , R ³ , R between the mesogenic structure parts Z, Z ′ in the curable compounds of the formulas (1), (2) and the cured sites A ¹ , A ² , A ³ , A ⁴ By introducing an oxyalkylene structure containing ⁴ with high molecular mobility, the molecular mobility at the curing site in the curing process can be improved even in a state where the mesogen structure is oriented during curing, and it is sufficient in a short time Can be cured.

The curing sites A ¹ , A ² , A ³ , and A ⁴ of the formulas (1) and (2) may be any of the functional groups that can be photocured or thermally cured. The acryloyl group and methacryloyl group suitable for photocuring are preferable.

The number of carbon atoms of R ¹ , R ² , R ³ and R ⁴ in formulas (1) and (2) is preferably 2 to 6 from the viewpoint of molecular mobility, and an ethylene group having 2 carbon atoms and 3 carbon atoms having 3 carbon atoms. More preferred is a propylene group.

  Examples of the mesogen structure parts Z and Z ′ in the formulas (1) and (2) include polyphenylene groups in which 1,4-phenylene groups are linked. The 1,4-phenylene group may be partially or wholly substituted with 1,4-cyclohexylene group. In addition, some or all of the hydrogen atoms of these 1,4-phenylene groups and substituted 1,4-cyclohexylene groups may be alkyl groups having 1 to 2 carbon atoms, halogen atoms, carboxyl groups, alkoxycarbonyl groups, etc. It may be substituted with a substituent.

  Preferable mesogen structure parts Z and Z ′ include a biphenylene group in which two 1,4-phenylene groups are connected (hereinafter, a biphenylene group in which two 1,4-phenylene groups are connected is also referred to as a 4,4-biphenylene group). ) Three linked terphenylene groups and those in which 1 to 4 of these hydrogen atoms are substituted with an alkyl group having 1 to 2 carbon atoms, a fluorine atom, a chlorine atom or a carboxyl group. Most preferred is a 4,4-biphenylene group having no substituent. All the bonds between 1,4-phenylene groups or 1,4-cyclohexylene groups constituting the mesogenic structure may be single bonds or any of the following bonds.

  M, n, o, and p in the formulas (1) and (2) are each independently preferably 1 to 10, and more preferably 1 to 4. It is because compatibility with a liquid crystal will fall if too large, and transparency of the cured resin after hardening will fall.

  FIG. 2 shows examples of curable compounds that can be used in the present invention. The mixture containing the liquid crystal and the curable compound may contain a plurality of curable compounds including the curable compounds represented by the above formulas (1) and (2). For example, when the mixture contains a plurality of curable compounds having different m, n, o, and p in formulas (1) and (2), the compatibility with the liquid crystal may be improved.

  The mixture containing a liquid crystal and a curable compound may contain a curing catalyst. In the case of photocuring, a photopolymerization initiator generally used for a photocurable compound such as benzoin ether, acetophenone, or phosphine oxide can be used. In the case of thermosetting, a curing catalyst such as peroxide, thiol, amine, or acid anhydride can be used depending on the type of curing site, and if necessary, curing aids such as amines can also be used. Can be used.

  The content of the curing catalyst is preferably 20% by weight or less of the curable compound to be contained, and more preferably 1 to 10% by weight when a high molecular weight or high specific resistance of the cured resin is required after curing.

  As a treatment method for aligning liquid crystal molecules so that the pretilt angle is 60 degrees or more with respect to the substrate surface, there is a method using a vertical alignment agent. The vertical alignment agent is, for example, a method using a surfactant, a method of treating the substrate interface such as a silane coupling agent containing an alkyl group or a fluoroalkyl group, or SE1211 manufactured by Nissan Chemical Industries, or JALS-682 manufactured by JSR. There is a method using a commercially available vertical alignment agent such as R3. In order to create a state in which the liquid crystal molecules are tilted in an arbitrary direction from the vertical alignment state, any known method may be adopted. These vertical alignment agents may or may not be rubbed. Alternatively, a method may be employed in which a slit is provided in the electrode or a triangular prism is disposed on the electrode so that the voltage is applied obliquely to the substrate.

  As the liquid crystal constituting the above mixture, either a positive or negative dielectric anisotropy can be used in combination with an alignment layer or the like, but the negative dielectric anisotropy is in terms of response speed and high transparency. It is preferable to use one. In order to reduce the driving voltage, it is preferable that the absolute value of the dielectric anisotropy is large. Moreover, when a dichroic dye is contained in the mixture, the light scattering state can be colored.

  The substrates 21 and 22 used in the electro-optic element 2 may be any substrate as long as transparency can be secured, and may be a glass substrate, a plastic sheet, or a film. The display surfaces of the first display body 1 and the electro-optical element 2 do not have to be flat, and may be curved.

  As the transparent electrodes 23 and 24 provided on the substrates 21 and 22, a transparent electrode material of metal oxide such as ITO (indium oxide-tin oxide) can be used.

  When using a liquid crystal having positive dielectric anisotropy as the liquid crystal, it is preferable from the viewpoint of transparency to rub the resin thin films 25 and 26 on the transparent electrode. A combination of alignment directions of the pair of alignment-treated substrates may be either parallel or orthogonal and may be arranged at an appropriate angle. In addition, when a liquid crystal having a negative dielectric anisotropy is used as the liquid crystal, it is preferable to use a vertical alignment agent or the like having a pretilt of 60 ° or more for the resin thin films 25 and 26 from the viewpoint of transparency. When a vertical alignment agent is used, rubbing is not necessary.

  The thickness of the liquid crystal layer 27 between the two substrates can be defined by a spacer or the like (not shown). The interval is preferably 1 to 50 μm, and more preferably 3 to 30 μm. If the thickness of the liquid crystal layer 27 is too narrow, the contrast is lowered, and if it is too large, the drive voltage tends to increase, which is often not preferable.

  Generally, in the scattering / transmission mode by PDLC, a light transmission state is taken when a voltage is applied between the electrodes, and a light scattering state is taken when the voltage application is stopped. In the case of the present invention, when the power is turned off and the electro-optic element is not used, it is transparent, and the light-scattering state is not applied when no voltage is applied so that the presence of the electro-optic element is not obstructive or does not give a feeling of pressure. I try to take it.

  In many cases, the liquid crystal layer 27 of the electro-optic element 2 manufactured as described above can have a very high response speed of 3 ms or less between the light transmission state and the light scattering state. In addition, compared with the conventional scattering / transmission mode, it is possible to obtain a very good transmission state even when viewed obliquely. For example, when the thermosetting compound having the composition exemplified above is used, it is possible to make almost no haze even when viewed at an angle of 40 ° from the vertical. That is, the viewing angle dependency of the light transmission state is good, and the display body is very transparent like glass.

  The first display 1 may be a mechanical display or an electric display such as a general liquid crystal display. The composite display device according to the present invention provides a new display by combining a first display body and a second display body, and these display states will be described with reference to the drawings.

  FIG. 3 is a diagram showing a speedometer for a vehicle, and FIG. 3A is a display in which the display of the first display body 1 and the display of the electro-optic element 2 as the second display body are combined. is there. FIG. 3B shows the display of the first display body 1, where the speedometer frame and numerical values are displayed (fixed display). Further, FIG. 3C shows the display of the electro-optical element 2, and here, the pointer of the speedometer is displayed. The pointer indicated by a broken line is an imaginary line, and the pixel of the electro-optic element 2 is formed at such a position, so that the pointer can be seen to move.

  FIG. 4 is also a diagram showing a vehicle speedometer, and FIG. 4A is a display in which the display of the first display body 1 and the display of the electro-optic element 2 as the second display body are combined. . FIG. 4B shows the display of the first display 1, and here the pointer of the speedometer is represented by a mechanical display. Further, FIG. 4C shows the display of the electro-optical element 2, and “55” and the numerical value of the speedometer are digitally shown. Note that the display of the electro-optical element 2 may be an arrow indicating the destination, such as a simple navigation system.

  Next, FIG. 5 will be described. FIG. 5A shows a display in which the display of the first display body 1 and the display of the electro-optical element 2 as the second display body are combined. FIG. 5B shows the display of the first display body 1, and FIG. 5C shows the display of the electro-optical element 2. Further, FIG. 5D also shows the display of the electro-optical element.

  The display of FIG. 5 shows the instrument panel for the vehicle, and the first display body 1 shows the speed and the tachometer. The display of the speed and tachometer may be a mechanical display or an electric display. FIG. 5C shows the instrument panel frame, where the hatched portion is in a light scattering state and the white portion is in a light transmitting state. An instrument panel display as shown in FIG. 5A can be represented by arranging each meter and direction indicator of the first display body 1 in this white portion (light transmission portion). Further, by applying a predetermined voltage to the light transmitting portion, the entire display area of the electro-optical element is made into a light scattering state as shown in FIG. 5D, and the display of the first display body 1 can be shielded. it can.

  Next, a mode in which the electro-optical element 2 is used as a shielding plate for the first display body 1 will be described with reference to FIGS. The hatched portions in FIGS. 6 and 7 indicate the light scattering state, and the white portions indicate the light transmitting state.

  6 (a) shows the total shielding state, FIG. 6 (b) shows the light transmission part only at the center, and the outer periphery of the light transmission part is light transmission in the order of FIG. 6 (c), FIG. 6 (d),. In FIG. 6 (h), the entire region is in a light transmission state. Therefore, with the passage of time from FIG. 6A to FIG. 6H over time, the first display body 1 gradually appears from the center. Moreover, when shielding the 1st display body 1, you may shield at once, and you may make it shield gradually from Fig.6 (h) to Fig.6 (a).

  FIG. 7A shows the total shielding state, and the light transmission state spreads outward so that the curtain opens in the order of FIG. 7B and FIG. 7C. The electro-optical element 2 may be displayed by forming a single band-shaped portion indicated by a broken line as one pixel, or by using a plurality of dots (pixels) to transmit and scatter light in the band-shaped portion indicated by the broken line. May be controlled.

  FIG. 8 also shows the instrument panel display for the vehicle. In front of the speedometer or the like of the first display body 1, an electro-optic element 2 according to the present invention is disposed so as to surround these instruments. The shaded portion in the figure is in a light transmitting state and is transparent. Therefore, it appears that the digital value “55” is displayed in a floating space.

  Thus, by using the composite display device according to the present invention, it becomes a transparent body that does not bother the presence of the electro-optical element 2 in the light transmission state, and in the light scattering state, it can be used as a shielding plate or a display body. Or can be used as In particular, when used as a display body, it is possible to give an impression that the display is generated in a space where there is nothing. Therefore, the present invention can provide a completely new display state that has never been seen before.

  Next, as another embodiment, a case where the first display body 1 is used as a mirror will be described. In FIG. 9, an electro-optical element 2 as a second display body is disposed in front of a vehicle rearview mirror. While the vehicle is running, a voltage is not applied between the transparent electrodes of the electro-optic element 2, and the light transmission state is established. By doing so, the electro-optical element 2 is transparent and does not interfere with the display of the rearview mirror. Note that the electro-optical element 2 may be displayed within a range that does not interfere with the field of view of the mirror even during traveling. Further, as information on the rear of the vehicle, the distance from the following vehicle obtained from the rear objective distance sensor, the distance from the wall surface when the vehicle is parked when the vehicle is parked, the object at the rear of the vehicle (person, For example, distance information with obstacles). Further, when a plurality of rear objective distance sensors are arranged in the vehicle, each distance information can be displayed on the rear mirror part (for example, the right end and the left end) so as to correspond to the position of the sensor. Cognition of the positional relationship with respect to obstacles improves. Note that not only the distance information but also the time information for the rear seat passenger, the estimated arrival time linked with the navigation system, and the like may be displayed as these information.

  When obtaining the rear information when the vehicle is parked, since the light-transmitting state is other than the display portion of the electro-optic element 2, the rear state and the rear objective distance can be obtained only by looking at the rearview mirror without hindering the visibility of the rearview mirror. Can be grasped. By using the back mirror as the first display body 1, the light beam of the display unit (light scattering unit) of the electro-optic element 2 is scattered twice, increasing the scattering intensity and displaying with high contrast. Can do. In this case, the electro-optical element 2 may be disposed so as to cover the entire surface of the rearview mirror, or may be disposed on a part of the rearview mirror, for example, the right half.

  As shown in FIG. 15, the electro-optical element 2 may be disposed between the observer 3 and the mirror that is the first display body 1. Unlike the rear-view mirror of the previous embodiment, this mirror reflects an instrument such as a speedometer in the instrument panel. Since the instrument can be seen through the mirror, information can be supplied not only to the driver but also to the passenger in the passenger seat depending on the mirror installation angle, etc. It can also be partially shielded by the optical element 2. Further, an illumination 4 such as a light source using a light guide or a projection light source may be provided. It is preferable to arrange the illumination 4 at a position where the illumination is not reflected on the observer 3.

  When the electro-optical element according to the present invention has sufficient scattering properties, light is scattered in all directions, so that the observer 3 can see the display of the electro-optical element 2 from various directions such as an oblique direction. . That is, the viewing angle of the electro-optic element 2 is very wide. In general, the ratio of the backscattering of light (the ratio of the light scattered to the first display body 1 side with respect to the electro-optical element 2) is the ratio of the forward scattering (the first display body with respect to the electro-optical element 2). Therefore, the illumination for illuminating the electro-optical element 2 is preferably arranged on the side opposite to the observer 3.

  As shown in FIG. 8, it is preferable to make the periphery of the electro-optic element 2 transparent because the state where the display appears to float in the air in the background behind the scene is emphasized. In order to achieve this purpose, it is preferable to seal the periphery of the electro-optic element 2 with a transparent resin layer and to make the frame transparent when there is a frame.

  Any known sealing agent can be used as long as it is a highly transparent resin. If a highly transparent resin is used, the electro-optic element 2 becomes more transparent on the entire surface, and the state that the display appears to float in the air is emphasized. For example, when a glass substrate is used, a state in which transparent glass floats in the air can be realized by using an epoxy resin or an acrylic resin having a refractive index close to that of glass.

  As the electro-optical element 2, elements of any size can be used including those having a diagonal length of as small as about 3 cm and those as large as about 3 m. Also, several electro-optical elements can be connected to form a large electro-optical element.

Further, it is preferable that at least one of the electro-optic elements 2 is subjected to an AR coating (low reflection coating) process made of a dielectric multilayer film having different refractive indexes such as SiO ₂ and TiO ₂ . Thereby, reflection of external light on the glass substrate surface is reduced, and the contrast is increased. Although it is better to apply the AR coating on both sides, it may be applied only to the viewer 3 side. Alternatively, a low reflective plastic film may be bonded.

  In the composite display device of the present invention, it is preferable to apply AR coating to both surfaces of the first display body 1. As another method for realizing low reflection, a resin having a refractive index equivalent to that of a substrate such as glass may be filled between the first display body 1 and the electro-optical element 2.

  Further, a UV cut filter may be disposed on the outer surface of the electro-optical element 2 in order to protect the liquid crystal layer 27 of the electro-optical element 2 from ultraviolet rays. The UV cut filter preferably has high transparency.

  If a plastic film is used as the AR coating or UV cut filter as described above and this is applied to the viewer 3 side, it can also function as a film tear prevention film particularly when used for vehicles. .

  As another embodiment, as shown in FIG. 11, two electro-optical elements 2 arranged between the first display body 1 and the observer 3 may be laminated. In order to perform a display in which the same pattern moves three-dimensionally, the display pattern is the same for one electro-optical element 11 and the other electro-optical element 12 disposed on the viewer 3 side. It is preferable. For example, if one electro-optical element 11 is a dot matrix type display pattern, the other electro-optical element 12 is also preferably a dot matrix type, and the size of each dot (pixel) is preferably the same. Note that the size of the display pattern may be changed in order to attract more attention to the observer. For example, when the size of the display pattern of the electro-optic element on the viewer side is increased, an impression that the display is imminent can be given to the viewer.

  When one electro-optical element 11 is a dot matrix type and a display “EMERGENCY” is formed as shown in FIG. 12, the other electro-optical element 12 can also form a display “EMERGENCY”. With reference to FIG. 12, it will be described that a new display can be obtained when the two electro-optic elements 11 and 12 are stacked so that the same display is possible. FIG. 12 is a perspective view showing a display state of the electro-optical elements 11 and 12. The electro-optic elements 11 and 12 both transmit light when no voltage is applied and scatter light when a voltage is applied.

  FIG. 12A shows a display state at a specific time. One electro-optical element 11 displays “EMERGENCY” and the other electro-optical element 12 displays nothing. At the next time shown in FIG. 12B, nothing is displayed on one electro-optical element 11, and “EMERGENCY” is displayed on the other electro-optical element 12. Further, at the next time shown in FIG. 12C, the display of “EMERGENCY” is again performed on one electro-optical element 11 and nothing is displayed on the other electro-optical element 12. By repeating these in time, the display can be moved spatially. Compared to the conventional blinking of a flat display, the observer 3 can be alerted by a three-dimensional display.

  Further, in order to improve the cosmetics and appeal of the display, it is preferable to provide the illumination 4 between the first display body 1 and the electro-optical element 11. The illumination 4 is preferably disposed at a position that does not hinder the visibility of the first display body 1. As a position that does not hinder the visibility, the illumination 4 is used as a projection light source, and the chief ray incident angle θ from the light source indicated by a broken line in FIG. 11 is the central portion of the electro-optical element 11. It is preferable that the angle is obliquely rearward at 45 ° to 60 ° with respect to the normal of the display surface.

  Further, by using a plurality of light sources having different colors as the illumination 4, the appeal can be further improved. Referring to FIG. 12, the electro-optic element 11 is irradiated with a light source that develops red color at the time of FIG. 12A, and the electro-optic element 12 is illuminated with a light source that emits green color at the time of FIG. In addition, the electro-optic element 11 is irradiated with a red light source at the time of FIG. That is, more attention can be drawn by displaying the display driving state and the illumination in synchronization.

  Furthermore, as shown in FIG. 13, the digital numeral portion is irradiated with a yellow light source in order to display yellow, and the arrow portion is irradiated with a red light source in order to display red in that area. May be performed. FIG. 13 is similar to FIG. 12 in which two electro-optical elements 11 and 12 are disposed between the first display 1 and the observer 3. The display state of the electro-optical elements 11 and 12 is shown in FIG. It is easy to understand and shown in a perspective view. FIG. 13A shows a digital numeral “55” and an “arrow” indicating the right direction on one electro-optical element 11 at a specific time, and nothing is displayed on the other electro-optical element 12. This indicates that there is no state. FIG. 13B shows the display state at the next time, and the digital numeral “55” of the electro-optical element 11 remains as it is, but the “arrow” of the electro-optical element 11 indicates the display state. In other words, an “arrow” is displayed on the electro-optical element 12. Further, FIG. 13C showing the display state at the next time shows a state in which digital numerals “55” and “arrow” are displayed on the electro-optical element 11 and nothing is displayed on the electro-optical element 12. ing.

  In the present embodiment, for example, two electro-optical elements 2 are stacked as shown in FIGS. 11 to 13. However, the number of electro-optical elements is not limited to two. Lamination may be provided. By increasing the number of stacks, the spatial mobility of display increases, and a more three-dimensional display can be obtained. In addition, the stacking mode includes two electro-optical elements that are in close contact, two electro-optical elements that sandwich an air layer, and two electro-optical elements that sandwich a transparent material.

  Referring to FIG. 14, it is preferable to fix the transparent substrates 21 and 22 constituting the electro-optic element with an adhesive spacer 29 from the viewpoint of improving the impact resistance of the electro-optic element 2 in the present invention. The adhesive spacer 29 may be one in which an adhesive resin is coated around a spherical spacer, but a columnar spacer made of an adhesive resin is preferable from the standpoint of adhesion. When the present invention is used for a composite display for a vehicle, the composite display is in a vibrating state when the vehicle is moving and when the vehicle engine is operating, so that the transparent substrate of the electro-optic element 2 can be more firmly fixed. preferable.

  The adhesive spacer 29 is preferably formed from a highly transparent material. In addition, the adhesive spacer 29 is preferably disposed in a portion (non-display portion) that does not need to be displayed in a scattered manner, but the display portion can be adjusted by reducing the area occupied by the adhesive spacer 29 as much as possible or adjusting the scattering power. You may arrange in.

  The electro-optic element can be driven by a conventionally known technique, static drive or duty drive. In addition, an active element such as a TFT or TFD may be used.

  Examples of the present invention are shown below. In the examples, “parts” means parts by weight.

[Example 1]
An electro-optic element 2 having a schematic cross-sectional view shown in FIG. 1 was prepared as follows. First, 95 parts of cyano nematic liquid crystal (BL-006 manufactured by Merck & Co., Inc.) having a positive dielectric anisotropy, 5 parts of the curable compound shown in FIG. 2A, and 0.2 parts of benzoin isopropyl ether. 2.5 parts of a chiral agent (mixture of S-811 and C15 manufactured by Merck Ltd. in a weight ratio of 1: 1) was blended to prepare a mixed composition.
Next, a pair of substrates on which the polyimide thin film formed on the transparent electrode is rubbed in one direction are opposed to each other so that the rubbing directions are orthogonal to each other, and a small amount of resin beads having a diameter of 13 μm are sprayed. The above mixture was injected into an electro-optic cell prepared by bonding together with an epoxy resin printed with a width of about 1 mm. While maintaining the cell 25 ° C., the dominant wavelength of about 365nm of HgXe lamp, 3 mW / cm ² from the upper side, and also irradiated from about 3 mW / cm ² of ultraviolet 3 minutes from the lower side, an electro-optic element 2 Obtained.

  The operation of removing the voltage after applying a rectangular wave of 50 Hz and 50 Vrms for 10 minutes to this electro-optic element was repeated 10 times. Thereafter, the transmittance was measured with a transmittance measurement system (F value of optical system: 11.5) using a measurement light source having a half wavelength width of about 20 nm with 530 nm as the center wavelength, and at 80% with no voltage applied. Yes, the value of contrast divided by the transmittance when 50 Vrms was applied was 28.

  A vehicle speedometer was used as the first display 1 so that the display shown in FIG. 3 was obtained. As a result, the observer 3 can clearly see that the pointer of the electro-optical element 2 indicates the vicinity of 60 indicated by the fixed display behind the electro-optical element.

[Example 2]
An electro-optical element 2 having the schematic cross-sectional view shown in FIG. 1 was produced as follows. First, 80 parts of nematic liquid crystal having negative dielectric anisotropy (AG-1016XX manufactured by Chisso Corporation), 20 parts of the curable compound shown in FIG. 2A, and 0.2 part of benzoin isopropyl ether are blended. Then, a mixed composition was prepared.

Next, a polyimide thin film is formed by a pair of glass substrates having a length of 100 mm, a width of 100 mm, and a thickness of 1.1 mm, in which a vertical alignment polyimide film (JALS-682-R3 manufactured by JSR) is formed on a transparent electrode. Installed so as to face each other, a small amount of resin beads having a diameter of 6 μm are disposed in the gap, and an epoxy resin layer having a width of about 1 mm is provided on the four sides of the substrate by printing, and is bonded and cured to form an electro-optic element. The peripheral portion of 2 was sealed with a transparent resin layer. Specifically, a part of the sealing agent is released, and after the sealing agent is cured, the mixed composition is injected into the liquid crystal cell thus formed. The peripheral sealing material 28 was completed by sealing with an epoxy resin and curing. Next, the curable compound was cured while the liquid crystal in which the curable compound was dissolved by the action of the polyimide film for vertical alignment was aligned in the direction perpendicular to the substrate surface, and the liquid crystal layer 27 was formed. Specifically, with the injected liquid crystal cell held at 40 ° C., about 2.5 mW / cm ² from the upper side and about 2.5 mW from the lower side by an Hg-Xe lamp having a dominant wavelength of about 365 nm. The electro-optic element was irradiated with UV light of / cm ² for 10 minutes and sealed with a transparent resin layer.

  Note that a transparent resin seal frame may be provided at the periphery of the electro-optic element to improve mechanical strength and prevent chemical alteration of the liquid crystal layer and the like. In this case, the electro-optical element is double-sealed with a transparent resin layer.

  The driving for switching the liquid crystal layer of the electro-optic element 2 between the light transmitting state and the light scattering state was performed by switching between a rectangular wave of 200 Hz and a voltage of 0V and 30V. The rise time was about 1.5 ms and the fall time was about 2 ms.

  A vehicle speedometer was used as the first display 1 so that the display shown in FIG. 4 was obtained. As a result, the observer 3 could simultaneously see the digital numerical display of the electro-optic element 2 and the pointer of the speedometer behind the electro-optic element. In addition, when no voltage is applied to the electro-optical element, the light transmission state is completely achieved. Therefore, when the electro-optical element is not used, there is a feeling of opening, and when the electro-optical element is used, a number floats in the space. I was able to give the impression of being.

[Example 3]
In the same manner as in Example 2, an electro-optical element 2 was produced. The electro-optical element 2 was disposed in front so as to cover the entire surface of the mirror, and the electro-optical element was driven in the same manner as in Example 1. The portion where no voltage was applied between the transparent electrodes of the electro-optic element remained transparent, and the visibility of the mirror was good. Further, the voltage application unit, that is, the display unit was in a light scattering state, and a bright and highly visible display was obtained.

  Although the first display body has been described as an instrument or a mirror as an embodiment of the present invention, it also includes an aspect in which the electro-optic element 2 is disposed on the dashboard of the vehicle as shown in FIG. In this aspect, the display of the first display body is the background. Since the electro-optic element according to the present invention is transparent, visibility is good except for the display portion, and the visibility is not hindered.

[Example 4]
Two electro-optic elements 2 were produced in the same manner as in Example 2. These two electro-optic elements were laminated in front of the instrument panel which is the first display body 1 as shown in FIG. As the illumination 4, a red LED and a green LED are arranged as a projection light source and installed behind the electrooptic element 11 so that θ is 45 °.

  Then, as shown in FIG. 12, the characters “EMERGENCY” were displayed on the electro-optical element 11, and nothing was displayed on the electro-optical element 12 at that time. In addition, nothing was displayed on the electro-optical element 11 at the next time, and “EMERGENCY” was displayed on the electro-optical element 12, and the display was repeated. Further, during the time displayed on the electro-optical element 11, the electro-optical element 11 is irradiated with red light by opening and closing a shutter (not shown), and a red “EMERGENCY” is displayed, which is displayed on the electro-optical element 12. During this time, the electro-optic element 12 is irradiated with green light by opening and closing the shutter to form a green “EMERGENCY” display. In this way, it was possible to obtain a display that appealed to the viewer, as well as a display that moved spatially and an unprecedented display that the display was different in color depending on the display location. .

[Example 5]
In order to improve the adhesion of the upper and lower transparent substrates 21 and 22 as the electro-optic element 2, the same procedure as in Example 2 was performed except that a transparent columnar adhesive spacer was provided between the two substrates instead of the resin beads in Example 2. Thus, an electro-optic element 2 was produced. The columnar adhesive spacer will be described in detail below. After forming a transparent electrode and a vertical alignment film on a transparent substrate, the columnar adhesive spacer is coated with a transparent adhesive spacer on the entire surface by spin coating and dried. did. Thereafter, the adhesive spacers were formed by photolithography so that the interval between the individual columnar adhesive spacers was 300 μm, the size of the columnar adhesive spacers was 20 μm in diameter, and the height was 6 μm. Then, the two transparent substrates were bonded together through a peripheral sealing material, and then put into a warm air furnace for a predetermined time, and both the transparent substrates were fixed.
The obtained electro-optic element was excellent in maintaining transparency even by vibration or impact. As shown in FIG. 15, the electro-optical element is disposed between the mirror of the first display body on which the speedometer is projected and the observer. The non-voltage application portion of the electro-optic element was highly transparent and the characters on the speedometer were clearly visible.

The conceptual diagram which shows the structure of this invention. The figure which illustrates curable resin which can be used for an electro-optical element. Explanatory drawing showing the display state of the composite display apparatus which concerns on this invention. FIG. 6 is another explanatory diagram different from FIG. 4 showing the display state of the composite display device according to the present invention. Other explanatory views different from FIGS. 4 and 5 showing the display state of the composite display device according to the present invention. Explanatory drawing which shows the use of an electro-optical element. Another explanatory view different from FIG. 6 showing the use of the electro-optic element. FIG. 7 is another explanatory diagram different from FIG. Explanatory drawing which shows other one Example of this invention. Explanatory drawing which shows the other Example of this invention. The conceptual diagram which shows the other Example of this invention. FIG. 12 is a perspective view showing a display state of the electro-optic element used in FIG. 11. FIG. 12 is a perspective view showing another display state of the electro-optic element used in FIG. 11. Sectional drawing of the other electro-optical element used for this invention. The conceptual diagram which shows the other Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st display body 2 Electro-optic element 3 Observer 4 Illumination 11 One electro-optic element 12 The other electro-optic element 21, 22 Glass substrate 23, 24 Transparent electrode 25, 26 Alignment film 27 Liquid crystal layer 28 Peripheral sealing material 29 Adhesive spacer

Claims (8)

  In a composite display device in which a second display body is disposed between a first display body and an observer, the second display body transmits light when no voltage is applied, and scatters light when a voltage is applied. A composite display device comprising an optical element.   The composite display device according to claim 1, wherein the light transmittance when no voltage is applied is 80% or more.   The composite display device according to claim 1, wherein a haze value at the time of light scattering is 80% or more.   The composite display device according to claim 1, wherein the first display body is a meter.   The composite display device according to claim 1, wherein the first display body is a mirror.   The composite display device according to claim 1, wherein a plurality of the second display bodies are arranged in a stacked manner.   The display pattern of the plurality of second display bodies is the same, and when one second display body is in a display state, the other second display body is in a non-display state. Composite display device.   The electro-optical element includes a liquid crystal layer sandwiched between a pair of substrates with transparent electrodes, and the liquid crystal layer is composed of a liquid crystal / cured resin composite including a liquid crystal and a cured product of a curable compound that can be dissolved in the liquid crystal. The composite display device according to claim 1.

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