JP2020056929A - Display - Google Patents

Abstract

To improve performance of a display.SOLUTION: A display DSP1 comprises: a substrate 10 that has flexibility; a substrate 20 that is opposite to the substrate 10 and has flexibility; a liquid crystal layer LQ that is between the substrate 10 and substrate 20; a plurality of polarizing plates PLB1 that are on the opposite side of the liquid crystal layer LQ with respect to the substrate 10; a polarizing film PLF1 that is between the plurality of polarizing plates PLB1 in plan view and has flexibility; a plurality of polarizing plates PLB2 that are on the opposite side of the liquid crystal layer LQ with respect to the substrate 20; and a polarizing film PLF2 that is between the plurality of polarizing plates PLB2 in plan view and has flexibility. A display area DA has an area DA1 and a plurality of areas DA2 adjacent to the area DA1. The area DA1 is a foldable area. The plurality of polarizing plates PLB1 and the plurality of polarizing plates PLB2 overlap the plurality of areas DA2. The polarizing film PLF1 and polarizing film PLF2 overlap the area DA1.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a display device and, for example, to a technology that is effective when applied to a bendable liquid crystal display device.

  As a mode of the display device, a display device such as a so-called foldable or bendable that can be bent in a display area is being studied (see JP-A-2017-126061 (Patent Document 1)).

JP 2017-126061 A JP 2002-228837 A

  The inventors of the present application have studied and found that, among the foldable display devices, a display device that controls display using a polarizer such as a polarizing plate has the following problems. In the case of a display device using a polarizer, a polarizing plate is attached to a panel having an electro-optic layer such as a liquid crystal layer. However, when the polarizing plate is disposed in the bending region, it is difficult to bend the display device with the hard polarizing plate. In addition, when the polarizing plate in the bent area is removed, display quality is reduced. An object of the present invention is to provide a technique for improving the performance of a display device.

  A display device according to one embodiment of the present invention includes a first substrate having flexibility, a second substrate facing the first substrate and having flexibility, the first substrate, and the second substrate. A plurality of first polarizers on the opposite side of the liquid crystal layer with respect to the first substrate, and a plurality of first polarizers in plan view, and A first polarizing film comprising: a plurality of second polarizing plates on the opposite side of the liquid crystal layer with respect to the second substrate; and a plurality of second polarizing plates in plan view, and having flexibility. And a second polarizing film provided. The display area has a first area and a plurality of second areas adjacent to the first area. The first area is a bendable area. The plurality of first polarizers and the plurality of second polarizers overlap the plurality of second regions. The first polarizing film and the second polarizing film overlap the first region.

  A display device according to another aspect of the present invention includes an electro-optic layer having a first surface, a retardation plate covering the first surface of the electro-optic layer, and an electro-optic layer, And a first polarizing film having flexibility between the plurality of first polarizing plates in plan view. In a plan view, the electro-optic layer has a first region and a plurality of second regions adjacent to the first region. The first area is a bendable area. The plurality of first polarizers overlap the plurality of second regions. The first polarizing film overlaps the first region.

FIG. 1 is a perspective view illustrating an example of a display device according to an embodiment. FIG. 2 is a plan view when the display device shown in FIG. 1 is expanded. FIG. 3 is a circuit block diagram illustrating a configuration example of a circuit included in each of a plurality of pixels illustrated in FIG. 2. FIG. 3 is a sectional view taken along line AA of FIG. 2. FIG. 3 is an enlarged sectional view of a part of a display area of FIG. 2. FIG. 5 is an enlarged cross-sectional view illustrating a structural example of the polarizing plate illustrated in FIG. 4. FIG. 5 is a plan view illustrating a planar positional relationship between the polarizing plate and the polarizing film illustrated in FIG. 4. It is an expanded sectional view of the display which is a modification of the display shown in FIG. FIG. 9 is a cross-sectional view illustrating a configuration example of the light source illustrated in FIGS. 4 and 8. FIG. 10 is a cross-sectional view illustrating a configuration example of a light source that is a modification example of FIG. 9. FIG. 11 is an enlarged cross-sectional view illustrating a configuration example of a display device that is another modification example of FIG. 4. It is an expanded sectional view which shows the example of a structure of the display apparatus which is another modification of FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. It should be noted that the disclosure is merely an example, and those skilled in the art can easily conceive of appropriate changes while maintaining the gist of the invention, which are naturally included in the scope of the present invention. In addition, in order to make the description clearer, the width, thickness, shape, and the like of each part may be schematically illustrated as compared with actual embodiments, but this is merely an example, and the interpretation of the present invention is not limited thereto. It is not limited. In the specification and the drawings, components similar to those described in regard to a drawing thereinabove are marked with the same or related reference numerals, and a detailed description is omitted as appropriate.

(Embodiment 1)
<Configuration of display device>
First, the configuration of the display device will be described. FIG. 1 is a perspective view illustrating an example of the display device of the present embodiment. FIG. 2 is a plan view when the display device shown in FIG. 1 is expanded. 1, illustration of the peripheral region PFR shown in FIG. 2 is omitted. In FIG. 2, the boundary between the display area DA and the peripheral area PFR in a plan view is indicated by a two-dot chain line. In FIG. 2, part of circuit blocks and wiring of a circuit included in the display device DSP1 is schematically illustrated by solid lines. In FIG. 2, the boundary between the area DA1 and the area DA2 is indicated by a dotted line. FIG. 3 is a circuit block diagram illustrating a configuration example of a circuit included in each of the plurality of pixels illustrated in FIG. FIG. 4 is a sectional view taken along line AA of FIG. Although FIG. 4 is a cross-sectional view, hatching of the substrate 10, the substrate 20, and the light source LS is omitted for easy viewing. Between the substrate 10 and the substrate 20 shown in FIG. 4, a plurality of members shown in FIG. 5 are formed in addition to the liquid crystal layer LQ. In FIG. 4, illustration of these members is omitted. FIG. 5 is an enlarged sectional view of a part of the display area of FIG.

  As shown in FIG. 1, the display device DSP1 of the present embodiment has a display area DA on which an image is formed in accordance with an externally supplied input signal. The display area DA is an effective area for displaying an image visually recognized by a viewer.

  In the display area DA, the area DA1 is a bendable area. In other words, the display device DSP1 has a structure that is assumed to be bent during use or while being carried. In the display area DA, the area DA2 is an area that is not assumed to be bent (in other words, is not bendable). The above-described structure that is assumed to be bent means that, in addition to a structure that can be simply bent physically, measures against a problem caused by bending the display area DA are taken. Therefore, for example, the area DA1 may have a structure that can be physically bent. The details of the problem caused by bending a part of the display area DA will be described later.

  The display area DA of the display device DSP1 has an area DA1 and a plurality (two in FIG. 1) of areas DA2 on both sides of the area DA1. In the case of the display device DSP1, by folding the display area DA, the size at the time of carrying can be reduced. In addition, the display device DSP1 can visually recognize an image on a large screen by expanding the folded display area DA as illustrated in FIG.

  Further, the display device DSP1 has a peripheral region PFR around the display region DA in plan view. In the peripheral area PFR, there is a sealing material BND surrounding the periphery of the display area DA. In the peripheral area PFR, there are a plurality of wirings connected to a plurality of transistors arranged in the display area DA.

  A plurality of pixels PX are arranged in the display area DA. The plurality of pixels PX are arranged in a matrix along the X direction and the Y direction crossing the X direction. Each of the plurality of pixels PX has a transistor Tr1 (see FIG. 3) functioning as a pixel selection switch, and a pixel electrode PE (see FIG. 3) connected to the transistor Tr1. In the display area DA, there are a plurality of scanning lines (gate lines) GL extending along the X direction and a plurality of video signal lines (source lines) SL extending along the Y direction. In the example shown in FIG. 2, the plurality of scanning lines GL are arranged in the Y direction, and the plurality of video signal lines SL are arranged in the X direction. In the display area DA, there is a common electrode CE. The common electrode CE is an electrode for supplying a common potential applied to each of the pixels PX, and for example, overlaps with a plurality of pixels PX.

  Each of the plurality of video signal lines SL is connected to the pixel electrode PE via the transistor Tr1, as shown in FIG. Specifically, the video signal line SL is connected to the source electrode SE of the transistor Tr1, and the pixel electrode PE is connected to the drain electrode DE of the transistor Tr1. When the transistor Tr1 is on, the video signal Spic is supplied from the video signal line SL to the pixel electrode PE. The video signal Spic is supplied from the signal line driving circuit SD. The video signal line SL in the display area DA is electrically connected to the signal line drive circuit SD via a connection wiring (also referred to as a lead wiring). The signal line driving circuit SD supplies the video signal Spic to the pixel electrode PE included in each of the plurality of pixels PX via the video signal line SL. The signal line driving circuit SD is arranged outside the display area DA shown in FIG.

  Each of the plurality of scanning lines GL drives the transistor Tr1, as shown in FIG. Specifically, a part of the scanning line GL forms a gate electrode GE of the transistor Tr1. Each of the plurality of scanning lines GL is drawn out to a peripheral region PFR outside the display region DA, and is connected to a scanning line driving circuit (gate driving circuit) GD shown in FIG. The scanning line driving circuit GD is a scanning signal output circuit that outputs a scanning signal Gsi input to the plurality of scanning lines GL. The scanning line driving circuit GD is arranged in the peripheral region PFR shown in FIG. The transistor Tr1 is a thin film transistor (TFT) that functions as a selection switch for selecting the pixel PX. Further, the scanning line GL includes the gate electrode GE of the transistor Tr1.

  In FIG. 4, the display device DSP1 includes a substrate 10. Further, the display device DSP1 includes a substrate 20 facing the substrate 10 via the liquid crystal layer LQ. The substrate 10 has a front surface (main surface, front surface) 10f facing the liquid crystal layer LQ, and a back surface (main surface, back surface) 10b opposite to the front surface 10f. The substrate 20 has a back surface (main surface, back surface) 20b facing the liquid crystal layer LQ, and a front surface (main surface, front surface) 20f opposite to the back surface 20b. The structure including the substrate 10, the substrate 20, and the liquid crystal layer LQ has a region (first region) DA1 and a plurality of regions (second regions) DA2 adjacent to the region DA1. The area DA2 is on both sides of the area DA1.

  Each of substrate 10 and substrate 20 is bendable in region DA1. Therefore, each of the substrate 10 and the substrate 20 has flexibility at least in the region DA1. In the case of the present embodiment, the substrate 10 and the substrate 20 have flexibility in the region DA1 and the plurality of regions DA2. In order to impart flexibility to the substrate 10 and the substrate 20, the substrate 10 and the substrate 20 are made of, for example, a resin material (organic material) containing a polymer such as polyimide, polyamide, polycarbonate, or polyester.

  The display device DSP1 includes a plurality of polarizing plates (first polarizing plates) PLB1 on the opposite side (in other words, the back surface 10b side) of the liquid crystal layer LQ with respect to the substrate 10, and a plurality of polarizing plates PLB1 in plan view. A polarizing film (first polarizing film) PLF1 which is between and has flexibility. The display device DSP1 includes a plurality of polarizing plates (second polarizing plates) PLB2 on the opposite side (in other words, the front surface 20f side) of the liquid crystal layer LQ with respect to the substrate 20, and a plurality of polarizing plates PLB2 in plan view. A polarizing film (second polarizing film) PLF2 which is between and has flexibility. Each of the polarizing plates PLB1, PLB2 and the polarizing films PLF1, PLF2 is a polarizer (polarizing member) that polarizes the light emitted from the light source LS. Details of these polarizers will be described later.

  The circuit component including the transistor Tr1 included in the pixel PX illustrated in FIG. 3 is formed on the substrate 10 as illustrated in FIG. The display device DSP1 has an insulating film 11 on the front surface 10f of the substrate 10 in the display area DA. The insulating film 11 is a base layer of various circuits including a TFT, and is made of, for example, an inorganic insulating material such as silicon nitride (SiN) or silicon oxide (SiO).

  A transistor Tr1 as a TFT is formed on the insulating film 11 as a base layer. FIG. 5 exemplarily shows one transistor Tr1. The transistor Tr1 is a thin film transistor (TFT). The transistor Tr1 includes a semiconductor region (semiconductor layer) SCR forming a channel region, a source region, and a drain region. The semiconductor region SCR is made of, for example, polysilicon and is formed on the insulating film 11. In the source region and the drain region of the semiconductor region SCR, a conductor pattern CDP connected to the source electrode SE or the drain electrode DE of the transistor Tr1 is formed. The conductor pattern CDP is formed by, for example, a sputtering method.

  The semiconductor region SCR is covered with an insulating film 12, which is a gate insulating film. The insulating film 12 is made of, for example, silicon oxide, and is deposited on the semiconductor region SCR and the conductor pattern CDP by, for example, chemical vapor deposition (CVD). Further, on the insulating film 12, a gate electrode GE is formed. The gate electrode GE is formed at a position overlapping the channel region of the semiconductor region SCR. In other words, the channel region of the semiconductor region SCR faces each other via the insulating film 12 that is a gate insulating film. The gate electrode GE is formed by patterning a metal film formed by a sputtering method or the like. Although not shown, a plurality of scanning lines GL shown in FIG. 2 are formed in the same layer as the gate electrode GE.

  The gate electrode GE and the insulating film 12 are covered with the insulating film 13. The insulating film 13 is made of, for example, silicon nitride, silicon oxide, or a stacked film thereof. The insulating film 13 is formed by, for example, a CVD method. On the insulating film 13, there are a source electrode SE and a drain electrode DE which are metal films. A contact hole penetrating the insulating films 12 and 13 in the thickness direction is formed in the insulating films 12 and 13, and the source electrode SE is connected to the conductor pattern CDP on the source region via the contact hole. The drain electrode DE is connected to the conductor pattern CDP on the drain region via a contact hole. The source electrode SE and the drain electrode DE are formed by, for example, a sputtering method. Further, a plurality of video signal lines SL shown in FIG. 2 are formed in the same layer as the source electrode SE and the drain electrode.

  The source electrode SE, the drain electrode DE, and the insulating film 13 are covered with the insulating film 14. The insulating film 14 is made of, for example, silicon nitride, silicon oxide, or a stacked film thereof. The insulating film 14 is formed by, for example, a CVD method.

  An organic film (planarization film, organic insulating film) 15 is formed on the insulating film 14. The organic film 15 is made of, for example, an organic material such as an acrylic resin. The thickness of the organic film 15 is larger than the thickness of each of the other insulating films 11, 12, 13, and 14. Further, the organic film 15 covers the transistor Tr1.

  On the organic film 15, a common electrode CE is formed. In a display period in which the display device DSP1 displays an image, a common drive potential corresponding to the plurality of pixels PX (see FIG. 2) is supplied to the common electrode CE. The common drive potential is supplied from the common electrode drive circuit CD shown in FIG. The common electrode CE is arranged over the entire display area DA. The common electrode CE is made of a transparent conductive material such as ITO (Indium tin oxide) or IZO (Indium Zinc Oxide). The common electrode CE is covered with the insulating film 16. The insulating film 16 is made of, for example, silicon nitride, silicon oxide, or a stacked film thereof. The insulating film 16 is formed by, for example, a CVD method.

  In the example shown in FIG. 5, the pixel electrode PE is formed on the insulating film 16. In the example shown in FIG. 5, the common electrode CE and the pixel electrode PE are formed in different layers. However, as a modified example, a plurality of common electrodes CE and a plurality of pixel electrodes PE may be formed on the same surface (for example, on the organic film 15), and may be alternately arranged so as to be adjacent to each other. The pixel electrode PE is preferably made of, for example, a transparent conductive material such as ITO or IZO or a metal material. The pixel electrode PE is connected to the drain electrode DE via a contact hole formed so as to penetrate the insulating film 16 and the organic film 15.

  In the display period, when different potentials are supplied to the pixel electrode PE and the common electrode CE, lines of electric force connecting the pixel electrode PE and the common electrode CE are generated. The liquid crystal molecules in the liquid crystal layer LQ are rotated by the electric field generated at this time.

  Further, each of the plurality of pixel electrodes PE is covered with the alignment film AL1. The alignment film AL1 is an insulating film having a function of aligning the initial alignment of the liquid crystal molecules included in the liquid crystal layer LQ, and is made of, for example, a polyimide resin. The alignment film AL1 is between the substrate 10 and the liquid crystal layer LQ, and is in contact with the liquid crystal layer. Further, the alignment film AL1 is in contact with the liquid crystal layer LQ. Details of the alignment film AL1 will be described later.

  Further, the display device DSP1 has a light-shielding film BM, a color filter CF, an insulating film OC1, and an alignment film AL2 between the rear surface (main surface, surface) 20b of the substrate 20 and the liquid crystal layer LQ.

  The color filter CF is formed on the back surface 20 b side of the substrate 20. In the color filter CF, three color filters CF of red (R), green (G), and blue (B) are periodically arranged. Further, a light-shielding film BM is arranged at the boundary between the color filters CF of the respective colors. The light shielding film BM is called a black matrix, and is made of, for example, a black resin or a low-reflection metal. The light-shielding film BM is formed, for example, in a lattice shape in plan view.

  The insulating film OC1 shown in FIG. 5 covers the color filter CF. The insulating film OC1 functions as a protective film that prevents impurities from diffusing from the color filter into the liquid crystal layer. The insulating film OC1 is an organic insulating film made of, for example, an acrylic photosensitive resin. The alignment film AL2 is disposed on the insulating film OC1. The alignment film AL2 is between the substrate 20 and the liquid crystal layer LQ and is in contact with the liquid crystal layer LQ. Each of the alignment films AL1 and AL2 is a photo-alignment film that is subjected to an alignment process by irradiating polarized ultraviolet light.

  Although not shown in FIGS. 4 and 5, a spacer member for controlling the gap between the opposing substrates (in other words, the thickness of the liquid crystal layer LQ) is provided between the substrate 10 and the substrate 20. Is arranged. The spacer member is a member provided on at least one of the substrate 10 and the substrate 20. For example, when a part of the substrate 20 is pushed into the substrate 10 side, the spacer member can support the gap between the substrates so as not to be too small. In the case where the display area DA includes the area DA1 which is bent as in the present embodiment, the area DA1 is easily bent, so that the gap between the substrates is easily changed.

  Therefore, in the region DA1, it is preferable that the substrate 10 and the substrate 20 are bonded via a spacer member. For example, a polymer pillar or wall is arranged in the area DA1, and the substrate 10 and the substrate 20 are bonded via the pillar or wall. Alternatively, there may be a configuration in which an adhesive is disposed on the top of a spacer member formed on one substrate, and the spacer member is bonded to the other substrate via the adhesive.

<Polarizer>
Next, a detailed structure of the polarizer (polarizing member) shown in FIG. 4 will be described. FIG. 6 is an enlarged cross-sectional view showing a structural example of the polarizing plate shown in FIG. FIG. 7 is a plan view showing a planar positional relationship between the polarizing plate and the polarizing film shown in FIG. In the case of a liquid crystal display device, two polarizers are arranged so as to face each other via the liquid crystal layer LQ. The polarizer is an optical filter that transmits light in a specific vibration direction and blocks light in another vibration direction. Since the liquid crystal molecules included in the liquid crystal layer LQ have a property of changing the signal direction of light depending on the alignment state, when the liquid crystal layer LQ is disposed between two polarizers, the liquid crystal molecules in the liquid crystal layer LQ By controlling the orientation of light, the transmittance of light can be controlled.

  In order to improve display quality, it is preferable to use a polarizer having a high degree of polarization. The degree of polarization is a light blocking ratio of light that vibrates in a direction intersecting the polarization axis, in other words, light that should be blocked by the polarizer. When a polarizer having a high degree of polarization is used as a polarizer for a display device, anger noise is reduced and display quality can be improved. As a polarizer having a high degree of polarization, an iodine-based polarizer can be mentioned. The iodine-based polarizer is a polarizer including a polymer material film such as a polyvinyl alcohol film containing an iodine compound. In the case of the present embodiment, each of the polarizing plates PLB1 and PLB2 shown in FIG. 4 includes a polarizing layer (polarizer) PL1, which is an iodine-based polarizer, as shown in FIG.

  The polarizing layer PL1, which is an iodine-based polarizer, has a high degree of polarization. However, from the viewpoint of mechanical strength, moisture resistance, and the like, the polarizing layer PL1 alone may be used by being attached to the substrate 10 or the substrate 20 shown in FIG. Is difficult. For this reason, each of the plurality of polarizing plates PLB1 and the plurality of polarizing plates PLB2 shown in FIG. 4 includes, as shown in FIG. 6, a polarizing layer PL1 in which an iodine compound is contained in a polyvinyl alcohol film which is a polymer material film; And a protective film PRF disposed so as to sandwich the polarizing layer PL1.

  Further, each of the polarizing plates PLB1 and PLB2 is a laminated film in which the polarizing layer PL1 is interposed between the protective films PRF, and it is difficult to form them directly on the substrate 10 or the substrate 20. Therefore, an adhesive layer AHL is formed on one of the two protective films PRF sandwiching the polarizing layer PL1, and the polarizing plate PLB1 is attached to the substrate 10 and the polarizing plate PLB2 is attached to the substrate 20 via the adhesive layer AHL. , Respectively.

  The protective film PRF adhered to the polarizing layer PL1 is made of, for example, a synthetic resin material such as triacetyl cellulose. In order to give the protective film PRF a function of reinforcing the mechanical strength of the polarizing layer PL1, the protective film PRF is formed to be hard. The thicknesses of the polarizing plates PLB1 and PLB2, which are the laminated films, are large. For example, in the example shown in FIG. 6, the thickness of the polarizing plate PLB1 or PLB2 (the total value of the thicknesses of the two protective films PRF, the polarizing layer PL1, and the adhesive layer AHL) is, for example, about 60 to 140 μm. . As described above, by adopting a laminated structure in which the polarizing layer PL1 is sandwiched between the hard protective films PRF, it is possible to prevent the polarizing characteristics of the polarizing layer PL1 from being deteriorated due to damage due to deformation or moisture absorption.

  However, it is difficult to arrange each of the polarizing plates PLB1 and PLB2 in a region DA1 (see FIG. 1) where bending is assumed. For example, the protective film PRF forming the polarizing plates PLB1 and PLB2 is not suitable for bending because it is hard and thick. Even if the protective film PRF can be bent, the polarizing layer PL1 disposed between the protective films PRF may be deformed or damaged by moisture absorption. Therefore, it is difficult to arrange the polarizing plates PLB1 and PLB2 including the polarizing layer PL1 in the area DA1 which is a bending area.

  Therefore, a method is considered in which the substrate 10 and the substrate 20 are exposed in a region DA1, which is a bending region, without disposing a polarizer. However, in this case, unpolarized light passes through the area DA1, which causes a reduction in display quality. For example, in the display area DA shown in FIG. 2, the light emitted from the light source LS (see FIG. 4) is transmitted through the light source LS without being polarized, so that the light is visually recognized as a white line. Further, when a light-shielding film (not shown) is arranged in the area DA1, the area DA1 is always visually recognized as a black line. It is sufficient that the width of the area DA1 is not visible, but when the display device DSP1 (see FIG. 1) is folded, it is necessary to increase the width of the area DA1 to some extent.

  As a result of the above study, the display device DSP1 of the present embodiment has the following structure. That is, as shown in FIG. 4, the plurality of polarizing plates PLB1 and the plurality of polarizing plates PLB2 included in the display device DSP1 overlap the plurality of regions DA2, and the flexible polarizing films PLF1 and PLF2 include the regions DA1. And overlap. In other words, in the area DA1, the polarizing films PLF1 and PLF2 are arranged, and the polarizing plates PLB1 and PLB2 are not arranged. With this structure, the display device DSP1 is a bendable display device and can suppress a decrease in display quality in the area DA1.

  Specifically, each of the polarizing films PLF1 and PLF2 is a coating type polarizer obtained by applying a raw material liquid to the area DA1. The coating type polarizer can be formed directly on the substrate 10 or the substrate 20. The coating type polarizer does not require the protective film PF and the adhesive layer AHL unlike the polarizing plates PLB1 and PLB2 shown in FIG. Therefore, in the case of the coating type polarizer, the film thickness can be reduced as compared with the polarizing plates PLB1 and PLB2. As shown in FIG. 4, the thickness TF1 of the polarizing film PLF1 and the thickness TF2 of the polarizing film PLF2 are smaller than the thickness TB1 of the polarizing plate PLB1 and the thickness TB2 of the polarizing plate PLB2. In the example shown in FIG. 4, the thickness TB1 of the PLB1 and the thickness TB2 of the polarizing plate PLB2 are, for example, about 80 to 100 μm. On the other hand, the thickness TF1 of the polarizing film PLF1 and the thickness TF2 of the polarizing film PLF2 are 10 μm or less (about several μm).

  Since the polarizing films PLF1 and PLF2 are thinner than the polarizing plates PLB1 and PLB2, they are easily bent. Therefore, the polarizing films PLF1 and PLF2 can be arranged in the bendable region DA1. In addition, when the polarization degrees are simply compared, the polarization degrees of the polarizing films PLF1 and PLF2 are lower than the polarization degrees of the polarizing plates PLB1 and PLB2. For this reason, the display quality of the area DA1 shown in FIG. 4 is lower than the display quality of the area DA2. However, since the region DA1 is in a state where the liquid crystal layer LQ is sandwiched between the polarizing films PLF1 and PLF2, it is possible to prevent the region DA1 from being viewed as a white line or a black line. That is, the display quality of the display area DA (see FIG. 2) including the area DA1 can be improved.

  As an example of the polarizing films PLF1 and PLF2 which are coating type polarizers, a polarizer containing a dichroic dye can be exemplified. The dichroic dye is an organic dye having a property of polarizing light by being distributed in a solute in the solute like the iodine contained in the polarizing plates PLB1 and PLB2. Iodine is also a dichroic substance, but is not included in the dichroic dye. The polarizing film PLF1 and the polarizing film PLF2 do not include the iodine compound contained in the polarizing plates PLB1 and PLB2. When an organic dye is used instead of iodine as the dichroic substance constituting the polarizer, the mechanical strength and moisture resistance of the polarizer can be improved. Therefore, it is preferable that the polarizing film PLF1 and the polarizing film PLF2 containing a dichroic substance are arranged in the area DA1 which is a bending area, and the polarizing plate PLB1 and the polarizing plate PLB2 containing an iodine compound are not arranged.

  However, as described above, the degree of polarization of a polarizer containing a dichroic dye is lower than that of a polarizer containing an iodine compound. Therefore, it is preferable that the polarizing plate PLB1 and the polarizing plate PLB2 having a higher degree of polarization than the polarizing film PLF1 and the polarizing film PLF2 are arranged in the non-bendable area DA2. In the case of the present embodiment, the polarizing film PLF1 is in contact with the plurality of polarizing plates PLB1 and is not arranged between the plurality of polarizing plates PLB1 and the substrate 10. Also. The polarizing film PLF2 is in contact with the plurality of polarizing plates PLB2 and is not disposed between the plurality of polarizing plates PLB2 and the substrate 20. As described later, as a modification example of the present embodiment, a polarizing film PLF1 and a polarizing film PLF2 may be arranged in the region DA2 in addition to the polarizing plates PLB1 and PLB2.

  When the coating type polarizing film PLF1 is formed in the region DA1, for example, after the polarizing plate PLB1 is attached to each of the plurality of regions DA2 of the substrate 10, the raw material liquid of the polarizing film PLF1 is placed between the adjacent polarizing plates PLB1. There is a method of applying. Alternatively, after one polarizing plate PLB1 is attached so as to cover the regions DA2 and DA1 of the substrate 10, the polarizing plate PLB1 in the region DA1 may be removed. As a method for removing the polarizing plate PLB1 in the region DA1, for example, a removing method by laser irradiation can be exemplified. As shown in FIG. 4, in a case where the polarizing film PLF1 is not arranged between the polarizing plate PLB1 and the substrate 10, it is preferable to attach the polarizing plate PLB1 to the substrate 10 before forming the polarizing film PLF1. . Note that the method of forming the coating-type polarizing film PLF2 in the region DA1 is the same as the method of forming the polarizing film PLF1, and thus redundant description will be omitted.

  Further, as described above, since the thicknesses of the polarizing plates PLB1 and PLB2 are large, the width of the region DA1 shown in FIG. The longer the separation distance W1 and the separation distance W2 between the adjacent polarizing plates PLB2, the better. In the example shown in FIG. 7, the separation distance W1 between the plurality of polarizing plates PLB1 adjacent to each other in plan view is larger than the thickness TB1 of each of the plurality of polarizing plates PLB1 shown in FIG. The distance W2 between the plurality of polarizing plates PLB2 adjacent to each other in plan view is larger than the thickness TB2 of each of the plurality of polarizing plates PLB2 shown in FIG. In this case, when the display device DSP1 is bent in the area DA1, it is possible to prevent the adjacent polarizing plates PLB1 or the adjacent polarizing plates PLB2 from contacting each other and hindering bending.

  As described above, the display device DSP1 can be easily bent by increasing the width of the region DA1, but the area of the region DA1 increases as the width of the region DA1 increases. As a result, the display quality of the area DA1 becomes important. In the case of the display device DSP1, as described above, since the polarizing film PLF1 and the polarizing film PLF2 are disposed in the area DA1, a decrease in display quality of the area DA1 can be suppressed.

  However, when the area DA1 and the area DA2 are compared, the area DA2 has higher display quality. Therefore, in consideration of the display quality of the entire display area DA, the area of the area DA1 is preferably as small as possible. In the case of the present embodiment, in plan view, the respective areas of the plurality of polarizing plates PLB1 and the plurality of polarizing plates PLB2 are larger than the area of the polarizing film PLF1 and the area of the polarizing film PLF2.

<Modification 1>
Next, various modifications of the above-described display device DSP1 will be described in order. FIG. 8 is an enlarged sectional view of a display device which is a modification of the display device shown in FIG.

  The display device DSP2 illustrated in FIG. 8 differs from the display device DSP1 illustrated in FIG. 4 in that the polarizing films PLF1 and PLF2 are spread over the entire substrate 10 or 20. Specifically, the polarizing film PLF1 provided in the display device DSP2 is formed between the plurality of polarizing plates PLB1 and the substrate 10 and between the adjacent polarizing plates PLB1. The polarizing film PLF2 is formed between the plurality of polarizing plates PLB2 and the substrate 20, and between adjacent polarizing plates PLB2.

  In the case of the display device DSP2, the polarizing films PLF1, PLF2 and the polarizing plates PLB1, PLB2 overlap in the area DA2. When two layers of polarizers having different degrees of polarization are stacked, light is polarized in each of the stacked polarizers. Therefore, in the case of the display device DSP2, the contrast of the display surface in the area DA is larger than that of the display device DSP1 shown in FIG.

  However, the thickness of the entire polarizing layer in the region DA2 (for example, the sum of the thickness of the polarizing plate PLB1 and the thickness of the polarizing film PLF1) is larger than that of the display device DSP1. Therefore, from the viewpoint of reducing the thickness of the polarizing layer in the region DA2 and reducing the area of the region DA, the display device DSP1 illustrated in FIG. 4 is more preferable.

  In the case of a structure in which the polarizing film PLF1 is disposed between the polarizing plate PLB1 and the substrate 10 as in the display device DSP2, the polarizing film PLF1 is formed before the polarizing plate PLB1 is attached to the substrate 10. Similarly, in the case where the polarizing film PLF2 is arranged between the polarizing plate PLB2 and the substrate 20, the polarizing film PLF2 is formed before the polarizing plate PLB2 is attached to the substrate 20.

<Modification 2>
Next, a configuration example of the light source LS shown in FIGS. 4 and 8 will be described. FIG. 9 is a cross-sectional view illustrating a configuration example of the light source illustrated in FIGS. 4 and 8. FIG. 10 is a cross-sectional view illustrating a configuration example of a light source that is a modification example of FIG.

  When the display device DSP1 shown in FIG. 4 or the display device DSP2 shown in FIG. 8 includes the bendable area DA1, the light source LS also needs to be bendable. In the case of the light source LS1 illustrated in FIG. 9, a light guide plate LGP and a light emitting unit EM1 connected to each of the plurality of light guide plates LGP are provided at positions overlapping the plurality of regions DA2. Further, the plurality of light guide plates LGP are covered with the diffusion plate DFP via the prism sheet PRS.

  When the light guide plate LGP is formed of a flexible material, one light guide plate LGP that overlaps the entire display area DA (see FIG. 2) without being divided into a plurality of light guide plates LGP may be used. . In the case of the example shown in FIG. 9, the light guide plate LGP is divided into a plurality (two in FIG. 9), and no light guide plate is arranged at a position overlapping the area DA1. Therefore, a light guide plate LGP made of a hard material such as an acrylic resin or a polycarbonate resin can be used.

  Like the light guide plate LGP, the prism sheet PRS and the diffusion plate DFP may be divided into a plurality of sheets. In the example illustrated in FIG. 9, however, the prism sheet PRS includes the area between the adjacent areas DA2 and DA2. It is arranged so as to cover DA1. In particular, when the diffusion plate DFP is arranged in the area DA1, luminance unevenness in the area DA1 can be reduced.

  In the case of the light source LS2 illustrated in FIG. 10, the light source LS2 includes a plurality of light emitting elements LEE mounted on a flexible substrate 30, and a diffusion plate DFP that covers the plurality of light emitting elements. A light emitting diode can be used as the light emitting element LEE. Light emitting diode elements have been miniaturized, such as mini LEDs, and the area DA1 can be bent even if the light emitting diode elements are arranged in the area DA1 to be bent.

<Modification 3>
Next, embodiments applied to devices other than the liquid crystal display device will be described. FIG. 11 is an enlarged sectional view showing a configuration example of a display device which is another modification example of FIG. FIG. 12 is an enlarged sectional view showing a configuration example of a display device which is still another modification example of FIG.

  The display device shown in FIG. 11 includes an electro-optic layer 40 having a front surface 40f, a retardation plate 41 covering the front surface 40f of the electro-optic layer 40, and an opposite side of the electro-optic layer 40 to the retardation plate 41. It has a plurality of polarizing plates PLB2 and a polarizing film PLF2 having flexibility between the plurality of polarizing plates PLB2 in plan view. In a plan view, the display area DA has an area DA1 and a plurality of areas DA2 adjacent to the area DA1. The area DA2 is on both sides of the area DA1. The area DA1 is a bendable area. The plurality of polarizing plates PLB2 overlap with the plurality of regions DA2, and the polarizing film PLF2 overlaps with the region DA1.

  In FIG. 11, the electro-optic layer 40 includes, for example, organic light-emitting diode elements that emit light by organic EL (electro-luminescence) for the number of pixels formed in the display area, or inorganic light-emitting diode elements such as micro LEDs. I have. When the electro-optical layer 40 including these light-emitting elements is used, the light source LS shown in FIGS. In the case of the display device DSP3 using the electro-optical layer 40 including the light emitting element, the retardation plate 41 and the polarizing plate PLB2 are sequentially laminated on the electro-optical layer 40. The phase difference plate 41 is, for example, a 波長 wavelength plate. When the display device DSP3 is bendable, the technique described with reference to the display device DSP1 in FIG. 4 and the display device DSP2 in FIG. 8 is applied to the portion of the polarizing plate PLB2 arranged on the retardation plate 41, thereby bending the display device DSP3. A decrease in display quality in the region can be suppressed.

  The display device DSP3 illustrated in FIG. 11 is similar to the display device DSP1 illustrated in FIG. 4 or the display device DSP2 illustrated in FIG. 8 except for the above-described differences. For example, the thickness TF2 of the polarizing film PLF2 is smaller than the thickness TB2 of the polarizing plate PLB2. Further, for example, the separation distance between the plurality of polarizing plates PLB2 adjacent to each other in plan view is larger than the thickness TB2 of each of the plurality of polarizing plates PLB2 shown in FIG. Each of the plurality of polarizing plates PLB2 includes a polarizing layer PL1 including a polyvinyl alcohol film which is a polymer material film containing an iodine compound, and a protective film PRF disposed so as to sandwich the polarizing layer PL1. On the other hand, the polarizing film PLF2 is a coating type polarizer, for example, a polarizer containing a dichroic dye.

  The display device DSP4 illustrated in FIG. 12 is a display device that can switch between a state in which visible light is transmitted and a state in which visible light is reflected by controlling the alignment of liquid crystal molecules in the liquid crystal layer LQ. The display device DSP4 includes a flexible substrate 10, a flexible substrate 20 facing the substrate 10, and a liquid crystal layer LQ between the substrates 10 and 20. The display device DSP4 includes a plurality of reflective polarizers PLR on the opposite side of the liquid crystal layer LQ with respect to the substrate 10, and a plurality of polarizers PLB2 on the opposite side of the liquid crystal layer LQ with respect to the substrate 20. And a polarizing film PLF2 having flexibility between the plurality of polarizing plates PLB2 in plan view. In a plan view, the display area DA has an area DA1 and a plurality of areas DA2 adjacent to the area DA1. The area DA2 is on both sides of the area DA1. The area DA1 is a bendable area. The plurality of reflective polarizing plates PLR and the plurality of polarizing plates PLB2 overlap with the plurality of regions DA2, and the polarizing film PLF2 overlaps with the region DA1.

  The reflective polarizing plate PLR has a property of transmitting light of a polarization axis and reflecting light in a direction perpendicular to the polarization axis. The display device DSP4 has a characteristic of transmitting visible light when, for example, a circuit for driving the liquid crystal layer LQ is turned on and an electric field is applied to the liquid crystal layer LQ. In addition, the display device DSP4 has a characteristic that the reflective polarizing plate reflects visible light when the circuit for driving the liquid crystal layer LQ is turned off and no electric field is applied to the liquid crystal layer LQ. In the example shown in FIG. 12, the same structure as that of the display device DSP1 described with reference to FIG. 4 is applied to the polarizer arranged on the opposite side of the reflective polarizing plate PLR.

  In addition, when the reflection and transmission are simply switched and used, a very high degree of polarization is not required. Therefore, a configuration in which the plurality of polarizing plates PLB2 shown in FIG. 12 are replaced with the polarizing film PLF2 and the entire display area DA is covered with the coating type polarizing film PLF2 can be obtained. In this case, the thickness of the device can be reduced.

  As the polarizing plates PLB1 and PLB2 shown in each of the above embodiments, an optical film for compensating the viewing angle may be used in addition to the polarizing plates shown here.

  Within the scope of the idea of the present invention, those skilled in the art can conceive various changes and modifications, and it is understood that these changes and modifications also belong to the scope of the present invention. For example, those skilled in the art may appropriately add, delete, or change the design of the above-described embodiments, or may add, omit, or change the conditions of the process. As long as it is provided, it is included in the scope of the present invention.

  INDUSTRIAL APPLICABILITY The present invention is applicable to a display device and an electronic device in which the display device is incorporated.

10, 20, 30 Substrate 10b, 20b Back surface 10f, 20f, 40f Front surface 11, 12, 13, 14, 16, OC1 Insulating film 15 Organic film 40 Electro-optic layer 41 Phase difference plate AHL Adhesive layer AL1, AL2 Alignment film BM Film BND Seal material CD Common electrode drive circuit CDP Conductor pattern CE Common electrode CF Color filter DA Display area DA1, DA2 Area DE Drain electrode DFP Diffusion plate DSP1, DSP2, DSP3, DSP4 Display EM1 Light emitting unit GD Scan line drive circuit GE Gate Electrode GL Scanning line Gsi Scanning signal LEE Light emitting element LGP Light guide plate LQ Liquid crystal layer LS, LS1, LS2 Light source PE Pixel electrode PFR Peripheral region PL1 Polarizing layer PLB1, PLB2 Polarizing plate PLF1, PLF2 Polarizing film PLR Reflective polarizing plate PRF Protective film PRS Prism sheet PX image SCR semiconductor region SD signal line driver circuit SE source electrode SL video signal line Spic video signal TB1, TB2, TF1, TF2 thickness Tr1 transistor

Claims (14)

A first substrate having flexibility;
A second substrate facing the first substrate and having flexibility;
A liquid crystal layer between the first substrate and the second substrate;
A plurality of first polarizers on the opposite side of the liquid crystal layer with respect to the first substrate;
A first polarizing film provided between the plurality of first polarizing plates in plan view and having flexibility;
A plurality of second polarizers on the opposite side of the liquid crystal layer with respect to the second substrate;
A second polarizing film between the plurality of second polarizing plates and having flexibility in a plan view;
Has,
The display area has a first area and a plurality of second areas adjacent to the first area,
The first region is a bendable region,
The plurality of first polarizers and the plurality of second polarizers overlap the plurality of second regions,
The display device, wherein the first polarizing film and the second polarizing film overlap the first region. In claim 1,
The display device, wherein a thickness of the first polarizing film and a thickness of the second polarizing film are smaller than respective thicknesses of the plurality of first polarizing plates and the plurality of second polarizing plates. In claim 2,
The separation distance between the plurality of first polarizing plates adjacent to each other in plan view is larger than the thickness of each of the plurality of first polarizing plates,
The display device, wherein a distance between the plurality of second polarizing plates adjacent to each other in plan view is larger than a thickness of each of the plurality of second polarizing plates. In any one of claims 1 to 3,
The display device, wherein in plan view, each area of the plurality of first polarizing plates and the plurality of second polarizing plates is larger than the area of the first polarizing film and the area of the second polarizing film. In any one of claims 1 to 4,
Each of the plurality of first polarizing plates and the plurality of second polarizing plates includes a first polarizing layer including a polymer material film containing an iodine compound, and a protective film disposed so as to sandwich the first polarizing layer. A display device comprising: In claim 5,
The display device, wherein the first polarizing film and the second polarizing film do not include the iodine compound included in the first polarizing layer. In claim 5,
The display device, wherein each of the first polarizing film and the second polarizing film is a film containing a dichroic dye. In any one of claims 1 to 7,
The first polarizing film is in contact with the plurality of first polarizing plates, and is not disposed between the plurality of first polarizing plates and the first substrate,
The display device, wherein the second polarizing film is in contact with the plurality of second polarizing plates and is not disposed between the plurality of second polarizing plates and the second substrate. In any one of claims 1 to 7,
The first polarizing film is formed between the plurality of first polarizing plates and the first substrate, and between adjacent first polarizing plates,
The display device, wherein the second polarizing film is formed between the plurality of second polarizing plates and the second substrate, and between adjacent second polarizing plates. An electro-optic layer having a first surface;
A retardation plate covering the first surface of the electro-optic layer;
A plurality of first polarizing plates on the opposite side of the electro-optic layer with respect to the retardation plate;
A first polarizing film provided between the plurality of first polarizing plates in plan view and having flexibility;
Has,
The display area has a first area and a plurality of second areas adjacent to the first area,
The first region is a bendable region,
The plurality of first polarizers overlap the plurality of second regions,
The display device, wherein the first polarizing film overlaps the first region. In claim 10,
The display device, wherein a thickness of the first polarizing film is smaller than a thickness of each of the plurality of first polarizing plates. In claim 11,
The display device, wherein a distance between the plurality of first polarizing plates adjacent to each other in plan view is larger than a thickness of each of the plurality of first polarizing plates. In any one of claims 10 to 12,
A display device, wherein each of the plurality of first polarizing plates includes a first polarizing layer including a polymer material film containing an iodine compound, and a protective film disposed so as to sandwich the first polarizing layer. . In any one of claims 10 to 12,
The display device, wherein the electro-optic layer is formed with a light-emitting diode element formed of an organic EL or a micro LED.

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