JP2015014926A - Liquid crystal display unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal display unit capable of stabilizing a detection result of a light detector installed in the liquid crystal display unit at high accuracy.SOLUTION: In a liquid crystal display unit 1, light emitters include a first light emitter that emits invisible light and a second light emitter that emits visible light. An array substrate includes a first light detector 2a having an invisible light sensitivity region that overlaps a red filter 14R in a planar view; a second light detector 2b that overlaps a color filter layer with low transmissivity of the invisible light emitted from the first light emitter or a black matrix BM; and a transistor that drives. The main coloring material of the red filter 14R is C.I. Pigment red 254.

Description

  The present invention provides a light receiving element comprising: a liquid crystal cell in which an array substrate and a counter substrate are bonded to each other with a liquid crystal layer facing each other; and a backlight unit provided on the back side of the liquid crystal cell and including a light emitting element. The present invention relates to a liquid crystal display device comprising

  In recent years, weight reduction of electronic devices using a liquid crystal display device has progressed. For example, the liquid crystal display device is provided in an information device such as a mobile phone or a mobile PC. As for the operation of the information device, for example, a technique for directly inputting to the liquid crystal display screen with a finger or a pointer is applied.

  The direct input method for the liquid crystal display screen is an on-cell method in which a touch panel with a sensing function is installed on the front surface of the liquid crystal panel and receives input by this touch panel. An in-cell system formed on a substrate and installed in a liquid crystal cell.

  As a technique used for the on-cell method, Patent Document 1 discloses a resistive film method, an electromagnetic induction method, a capacitance method, and an optical touch panel. However, the on-cell method in which the touch panel is disposed on the surface of the liquid crystal panel causes the thickness and weight to increase because the thickness and weight of the touch panel are added to the liquid crystal display device. Furthermore, liquid crystal display quality may deteriorate due to light reflection on the surface of the touch panel and the inner surface of the touch panel.

  On the other hand, the in-cell method in which the sensor is provided in the liquid crystal cell is preferable because the thickness of the liquid crystal display device is not increased as the liquid crystal display device and the display quality is hardly lowered. Optical sensors are being developed as sensors with sensing functions.

  In liquid crystal display devices used in information equipment, stereoscopic image display is being used. For example, technical requirements such as a request for a click feeling in a button display with a stereoscopic display effect, prevention of malfunction by finger input, etc. Is increasing. For finger input, there is a method in which a touch panel is externally attached to the surface of the liquid crystal display device. In order to reduce the weight, an optical sensor is built in a liquid crystal panel, and an input method using the optical sensor is being developed. A liquid crystal display device incorporating this optical sensor may need to be compensated for in order to prevent malfunction caused by finger input due to the influence of temperature and the influence of a backlight light source.

  Further, in a silicon photodiode having polysilicon or amorphous silicon as a channel layer, dark current is generated due to a change in environmental temperature or the like, and noise other than observation light may be added to observation data. For example, in a silicon photodiode having a crystal grain boundary such as polysilicon or continuous grain boundary silicon, variation in the position of the grain boundary directly becomes variation in photodiode characteristics, and a plurality of light beams that are homogeneous in the screen of the liquid crystal display device. It may be difficult to form a sensor. Compared with this silicon photodiode, the phototransistor characteristics of an optical sensor using an oxide semiconductor, which will be described later, are extremely uniform.

  Techniques for performing arithmetic correction using a photodiode that corrects dark current are disclosed in Patent Documents 2 and 3. These patent documents disclose dark current correction technology using an image sensor, but disclose processing technology for stable input and noise caused by reflected light when an oxide semiconductor photodiode is applied to a display device. Absent.

  Patent Document 4 discloses a technique for emitting sensing specialized light from an oblique direction in order to perform stable input when a light receiving element is used as a touch sensor. However, Patent Document 4 discloses a technique for processing noise caused by reflected light in a liquid crystal cell, the use of a light-receiving element made of an oxide semiconductor having a uniform characteristic with little characteristic variation among a plurality of elements, and a light-receiving element for signal compensation. Does not disclose a more stable input technique.

  In the technique of Patent Document 4, the specialized sensing light is always emitted in a direction different from the direction of the observer through the slit of the light shielding layer, but the cross section of the notch portion of the black matrix and the metal of the transistor such as a thin film transistor (TFT). Sensing specialized light may enter the observer's eyes due to irregular reflection from the wiring, light diffraction, and the like, and display quality may deteriorate. Further, Patent Document 4 is augmented by means of switching the intensity of obliquely emitted light depending on the purpose of use of the liquid crystal display device, such as image quality priority, security, or finger input, and the contrast (brightness difference) of image display. It does not disclose any means for reducing signal variations due to reflected light.

  In recent years, it has been noted that not only a transistor having an oxide semiconductor called IGZO as a channel layer but also a switching element for driving a liquid crystal, the switching element of the silicon photodiode is used as a driving element for a liquid crystal or a light receiving element. Has been. Since an oxide semiconductor has an extremely small dark current as compared with a silicon semiconductor, an advantage that it can be driven with low power consumption, including driving of a silicon photodiode and driving of a liquid crystal, is attracting attention.

  Further, a transistor in which a channel layer is formed using an oxide semiconductor has uniform characteristics with little variation even when a plurality of transistors are formed in a large area.

  Patent Documents 5 and 6 disclose techniques related to a light receiving element in an optical sensor using an oxide semiconductor. Patent Document 5 discloses an optical sensor technique mainly applied to a display using an organic substance as a light emitting layer. Patent Document 6 relates to a display device including an optical sensor for position detection in addition to an optical sensor as an area sensor. However, Patent Literature 5 and Patent Literature 6 do not disclose a liquid crystal driving technique for emitting oblique light.

  Patent Document 7 relates to an active matrix display substrate that includes a thin film transistor as a liquid crystal driving transistor, and describes a copper wiring technique as a metal wiring of the transistor. However, neither the sensitivity improvement technology of an optical sensor nor the oxide semiconductor technology is disclosed. In Patent Document 3, as in claim 3, wet etching is performed on copper or an alloy containing copper using an alkaline aqueous solution containing an oxidizing agent. However, it is difficult to perform wet etching so as not to damage the amorphous silicon constituting the TFT used as the transistor in this case. In addition, when copper or an alloy containing copper is subjected to dry etching, contamination by copper ions is significant, and it is further difficult to perform dry etching so as not to damage amorphous silicon. When copper wiring is applied as the metal wiring of a transistor, there is contamination of the channel portion in dry etching when forming a channel layer of amorphous silicon, and copper wiring in the TFT process of an amorphous silicon semiconductor has not been put into practical use. Therefore, in the liquid crystal display device only used for display as in Patent Document 7, there is almost no advantage of using copper as the wiring, and the fact is that the metal wiring of aluminum is used as the metal wiring of the TFT. .

JP-A-10-171599 JP 2002-335454 A JP 2007-18458 A WO2009 / 116205 JP 2010-186997 A JP 2011-118888 A JP-A-10-307303

  The present invention has been made in view of the above circumstances, and is provided with a liquid crystal cell in which an array substrate and a counter substrate are bonded to face each other through a liquid crystal layer, and provided on the back side of the liquid crystal cell. An object of the present invention is to provide a liquid crystal display device including a backlight unit including an element and including a light receiving element, in which a detection result by the light receiving element is highly accurate and stable. In addition, it is possible to perform sensing using a laser pointer such as a non-visible light / visible light LED, which has been difficult with a touch panel such as a conventional liquid crystal display device.

In order to solve the above problems, a liquid crystal cell in which an array substrate and a counter substrate are bonded to each other via a liquid crystal layer, and a backlight unit including a light emitting element, which is provided on the back side of the liquid crystal cell, are provided. A liquid crystal display device,
The light-emitting element includes a first light-emitting element that emits invisible light, and a second light-emitting element that emits visible light,
The counter substrate corresponds to a plurality of pixels or sub-pixels and forms a plurality of pixel openings divided in a matrix in plan view, and a red filter, a green filter, and a blue filter corresponding to the plurality of pixel openings. A color filter layer including a filter,
The array substrate has a first light receiving element having at least a non-visible light sensitivity region overlapping the red filter in a plan view, and the color filter layer having a low transmittance of the non-visible light emitted from the first light emitting element or A second light receiving element that overlaps the black matrix; a light guide electrode that drives a liquid crystal contained in a liquid crystal layer to emit the invisible light; and a liquid crystal in the liquid crystal layer that emits the visible light. A pixel electrode to be driven, and a transistor for driving one or both of the light guide electrode and the pixel electrode,
The red filter has a main colorant C.I. I. The present invention provides a liquid crystal display device characterized by being CI Pigment Red 254.

Further, the wavelength of the invisible light emitted from the first light emitting element is in the range of 360 nm to 400 nm,
In addition, the color filter layer or the black matrix having a low transmittance of invisible light emitted from the first light emitting element on which the second light receiving element overlaps is the green filter or the black matrix. The liquid crystal display device according to claim 1 is provided.

In addition, the wavelength of the invisible light emitted from the first light emitting element is in the range of 700 nm to 850 nm,
In addition, the color filter layer or the black matrix having a low transmittance of invisible light emitted from the first light emitting element on which the second light receiving element overlaps, the green filter, the blue filter, or the black 2. The liquid crystal display device according to claim 1, wherein the liquid crystal display device is a matrix.

In addition, the transistor is disposed below the light receiving element,
The metal wiring of the transistor has a two-layer structure of a metal layer made of copper or a copper alloy and a lower metal layer as viewed from the liquid crystal layer side, and two or more kinds of metals of gallium, indium, zinc, tin, and yttrium A liquid crystal display device including a channel layer containing an oxide is provided.

The light guide electrode further drives the liquid crystal contained in the liquid crystal layer for emission of the visible light,
The light emission timing of the second light-emitting element and the plurality of electrodes are synchronized with the light emission timing of the first light-emitting element and the liquid crystal driving voltage application timing of the light guide electrode. Further comprising a control means for synchronizing the liquid crystal driving voltage application timing.
The present invention provides a liquid crystal display device.

Further, the black matrix includes oblique light openings formed on two sides facing each other in a plan view,
The pixel electrode is for driving a liquid crystal corresponding to the pixel opening, and the light guide electrode is for driving a liquid crystal corresponding to the oblique light opening. A liquid crystal display device is provided.

  In addition, the liquid crystal layer provides a liquid crystal display device including liquid crystal with initial vertical alignment.

  An aspect of the present invention includes a liquid crystal cell in which an array substrate and a counter substrate are bonded to each other with a liquid crystal layer facing each other, and a backlight unit that is provided on the back side of the liquid crystal cell and includes a light emitting element. In a liquid crystal display device having a light receiving element, a red filter having a high transmittance of invisible light is used, and a metal wiring having a high reflectance of invisible light is used as a wiring of a transistor as necessary. It is possible to stabilize the detection result of the light receiving element provided in the above with high accuracy.

It is a fragmentary top view which shows an example of the liquid crystal display device which concerns on 1st Embodiment. 1 is a partial cross-sectional view illustrating an example of a liquid crystal display device according to a first embodiment. It is a top view which shows an example of the arrangement state of the sub pixel of the liquid crystal display device which concerns on 1st Embodiment. It is sectional drawing which shows an example of arrangement | positioning of the light receiving element of the liquid crystal display device which concerns on 1st Embodiment. It is sectional drawing which shows an example of the liquid crystal display device which concerns on 1st Embodiment. 4 is a partial cross-sectional view illustrating an example of a state in which a liquid crystal driving voltage is applied only to a first pixel electrode of the liquid crystal display device according to the first embodiment. FIG. 4 is a partial cross-sectional view illustrating an example of a state in which a liquid crystal driving voltage is applied only to a second pixel electrode of the liquid crystal display device according to the first embodiment. FIG. It is a fragmentary sectional view which shows an example of the state which applied the liquid crystal drive voltage to the light guide electrode of the liquid crystal display device which concerns on 1st Embodiment. It is a fragmentary sectional view showing an example in the state where a liquid crystal drive voltage was applied only to the 1st pixel electrode of the liquid crystal display concerning a 2nd embodiment. It is a fragmentary sectional view showing an example in the state where a liquid crystal drive voltage was applied only to the 2nd pixel electrode of a liquid crystal display concerning a 2nd embodiment. It is a fragmentary sectional view showing an example in the state where a liquid crystal drive voltage was applied to both pixel electrodes of a liquid crystal display concerning a 2nd embodiment. It is a fragmentary top view which shows an example of the liquid crystal display device which concerns on 4th Embodiment. It is a fragmentary sectional view showing an example of a liquid crystal display concerning a 4th embodiment. It is a fragmentary sectional view showing an example in the state where a liquid crystal drive voltage was applied only to the 1st pixel electrode of a liquid crystal display concerning a 4th embodiment. It is a fragmentary sectional view showing an example in the state where a liquid crystal drive voltage was applied only to the 2nd pixel electrode of a liquid crystal display concerning a 4th embodiment. It is a fragmentary sectional view showing an example in the state where the liquid crystal drive voltage was applied only to the 1st light guide electrode of the liquid crystal display concerning a 4th embodiment. It is a fragmentary sectional view showing an example in the state where the liquid crystal drive voltage was applied only to the 2nd light guide electrode of the liquid crystal display concerning a 4th embodiment. It is a fragmentary sectional view showing an example of a liquid crystal display concerning a 5th embodiment. It is a top view which shows the 1st example of the relationship between the planar shape of the sub pixel which concerns on 6th Embodiment, and the shape of a pixel electrode and a light guide electrode. It is a top view which shows the 2nd example of the relationship between the planar shape of the sub pixel which concerns on 6th Embodiment, and the shape of a pixel electrode and a light guide electrode. It is a top view which shows the 3rd example of the relationship between the planar shape of the sub pixel which concerns on 6th Embodiment, and the shape of a pixel electrode and a light guide electrode. The transmittance characteristics of the organic pigment that can be employed in the present invention in the light wavelength range of 350 nm to 750 nm. It is sectional drawing which shows the example of the 1st light receiving element part of the liquid crystal display element which concerns on 3rd Embodiment. It is a reflectance characteristic figure of copper. It is explanatory drawing which shows the sensitivity area | region of a silicon-type photodiode. It is explanatory drawing of the visibility of a human eye.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same or substantially the same functions and components are denoted by the same reference numerals, and will be described as necessary.

  In each embodiment, only characteristic portions will be described, and description of portions that are not different from the components of a normal liquid crystal display device will be omitted.

  In each embodiment, the single color display unit of the liquid crystal display device is assumed to be one subpixel or one pixel.

  In each embodiment, the case where the liquid crystal is a vertically aligned liquid crystal having a negative dielectric anisotropy will be described as a representative example, but a horizontally aligned liquid crystal having a positive dielectric anisotropy may be applied. Good. The rotation direction (operation direction) of the liquid crystal molecules when the liquid crystal driving voltage is applied may be parallel to the substrate surface or may be a direction rising in the vertical direction. The direction of the voltage applied to the liquid crystal molecules of the liquid crystal driving voltage may be horizontal, two-dimensional or three-dimensionally oblique, or vertical.

Common representative points in each embodiment are:
(A) A liquid crystal display device is a light emitting element that emits invisible light having a wavelength of 360 to 400 nm or 700 to 850 nm as illumination light in addition to a light source that emits visible light in a visible wavelength range to a backlight unit. Providing
(B) The light emitted from the first light emitting element is used as illumination light for illuminating an input indicator such as a finger or a pointer approaching the liquid crystal screen,
(C) the first light receiving element is disposed at a position overlapping with a red filter having a high transmittance of invisible light in a plan view;
(D) The second light receiving element is disposed at a position overlapping with a color filter layer or a black matrix having a low transmittance of invisible light emitted from the first light emitting element in plan view.

  Note that the visible light referred to in the present invention refers to light having a wavelength range of 400 nm to 700 nm with high visibility to human eyes, as shown in FIG. 26, for example, and light having a wavelength range outside the range refers to invisible light. For example, as shown in FIG. 27, the sensitivity region of a silicon-based photodiode is approximately 300 nm to 800 nm, and light can be received in the light wavelength range of 300 nm to 400 nm and 700 nm to 900 nm with low visibility.

  The pixel electrode and the light guide electrode described in detail in each embodiment may be used as the same electrode by combining these functions. On the other hand, there is one pixel electrode to which various voltages for gradation display are applied and one light guide electrode to which a specific voltage for emitting illumination light at a specific level (or a plurality of levels) is applied. The sub-pixels or pixels may be arranged in different configurations. An example in which the pixel electrode and the light guide electrode are driven by different transistors will be described in the first embodiment, and an example in which the pixel electrode and the light guide electrode are integrated will be described in the second embodiment.

  As a semiconductor applicable to the light receiving element, an amorphous silicon semiconductor having sensitivity from the visible region (for example, light wavelength, 400 nm to 700 nm) to infrared region, a polycrystalline silicon semiconductor having main sensitivity in the near ultraviolet region and blue wavelength region, There are a microcrystalline silicon semiconductor, a silicon germanium (SiGe) semiconductor, an oxide semiconductor typified by IGZO and ITZO, and the like.

  When these semiconductors are used, it is desirable to adjust the band gap to give the sensitivity range of the optical sensor to the target wavelength range. In the SiGe semiconductor, the band gap can be continuously changed by the addition ratio of Ge, the light receiving wavelength of the light receiving element can be adjusted, and the sensitivity in the infrared region can be imparted. A SiGe semiconductor having a Ge concentration gradient can also be used. For example, if GaAs, InGaAs, PbS, PbSe, SiGe, SiGeC or the like is used, an optical sensor suitable for infrared light can be produced.

  A liquid crystal display device including a light receiving element is easily affected by temperature and a backlight light source. In order to prevent an input malfunction of a finger or a laser due to noise caused by a backlight or external light, compensation of the light receiving element may be required in some cases. When a silicon photodiode having a channel layer formed of polysilicon or amorphous silicon is used as a light receiving element, a dark current is generated due to a change in environmental temperature or the like, and noise that is not observation light is added to observation data. There is a case.

  As a transistor for driving a liquid crystal or a light receiving element, a phototransistor having an oxide semiconductor as a channel layer can be employed. Here, an oxide semiconductor is an oxide semiconductor containing two or more metal oxides of indium, gallium, tin, zinc, hafnium, yttrium, titanium, germanium, and silicon. As this oxide semiconductor, a composite metal oxide of indium, gallium, and zinc called IGZO can be exemplified. The channel layer formed using an oxide semiconductor may be amorphous or crystallized, but it is preferable to crystallize from the viewpoint of stability of electric characteristics (eg, Vth) of the transistor. The thickness of the channel layer of the oxide semiconductor can be selected from a range of 2 nm to 80 nm, for example.

  As described above, when a light receiving element having sensitivity also in the invisible light region is used, various functions including optical communication can be provided by receiving light in each wavelength region in a wide wavelength region. The present inventors have found that the red filter according to the present invention has transmission characteristics in a wide wavelength range including an ultraviolet region and an infrared region, and enables a wide application range by the present application. For example, the red filter has a high transmittance in the red region and the infrared region of visible light, so it can transmit signals such as fingers and blood vessels of the human body as light, and is sensitive to the red region and the infrared region of visible light. It is applicable to biometric authentication by receiving light with a certain light receiving element, for example, a photodiode made of silicon semiconductor.

(First embodiment)
In this embodiment, the pixel electrode and the light guide electrode are driven separately by different transistors. The driving timings of the different transistors may overlap. As the transistor, for example, a transistor including an oxide semiconductor as a channel layer can be used. The transistor is not limited to this, and a transistor of polysilicon or a microcrystalline silicon semiconductor can also be used.

  The wavelength of invisible light applied to this embodiment will be mainly described below with an example of a short wavelength in the range of 360 nm to 400 nm.

  A liquid crystal driving voltage for causing the first light emitting element to emit invisible light (illumination light) that is light for illuminating the input indicator is applied to the light guide electrode. When the light receiving element receives and senses the invisible light, the same voltage is uniformly applied to each light guide electrode in the entire liquid crystal display screen. However, the voltage applied to each light guide electrode can be set to a plurality of levels according to the intensity switching of the emitted light, as will be described later. The light guide electrode is different from the pixel electrode in which various drive voltages are applied at various timings for gradation display.

  In the configuration in which the light guide electrode and the pixel electrode according to the second embodiment described later are used together, short wavelength light with a wavelength of 360 nm to 400 nm (invisible light) or long wavelength light with a wavelength of 700 nm to 850 nm (invisible light). It is preferable that each of the light-emitting element that emits light and the second light-emitting element (visible light source, for example, an LED that emits red, green, or blue light) emits light at different timings.

  In the present embodiment, a light receiving element is provided as an example of an optical sensor, and noise based on reflected light in the liquid crystal panel is removed from the observation value by the light receiving element to obtain a highly accurate, uniform and stable observation value. A liquid crystal display device capable of 3D image display (stereoscopic display) or 2D image display will be described.

  In the present embodiment, a light receiving element, a cell structure that emits illumination light, a liquid crystal operation associated with the light guide electrode and the light guide electrode, and a three-dimensional image display associated with the pixel electrode will be mainly described.

  FIG. 1 is a partial plan view showing an example of a liquid crystal display device according to the present embodiment. FIG. 1 shows a state in plan view of the liquid crystal display device 1 according to the present embodiment, that is, a state viewed from the observer side.

  FIG. 2 is a partial cross-sectional view showing an example of the liquid crystal display device 1 according to the present embodiment. FIG. 2 is a cross-sectional view taken along the line A-A ′ of FIG. 1. FIG. 2 shows a cross section perpendicular to the long axis direction of the color filter such as the red filter 14R, the comb-like or striped pixel electrodes 3a and 3b and the light guide electrodes 3c and 3d provided in the liquid crystal display device 1. Represents. In FIG. 2, the vertical alignment film, the polarizing plate, the phase difference plate, and the light receiving elements 2a and 2b shown in FIG. 1 are not shown. As will be described later, the liquid crystal display device 1 according to the present embodiment can switch between three-dimensional image display and normal two-dimensional image display.

  FIG. 3 is a plan view showing an example of an arrangement state of sub-pixels in the liquid crystal display device 1 according to the present embodiment.

  FIG. 4 is a cross-sectional view showing an example of the arrangement of the light receiving elements 2a and 2b of the liquid crystal display device 1 according to the present embodiment. 4 is a B-B ′ cross section of FIG. 1, and represents a cross section perpendicular to the longitudinal direction of, for example, the red filter 14 </ b> R included in the color filter layer 14 provided in the liquid crystal display device 1. The illustration of the vertical alignment film, the polarizing plate, and the retardation plate is omitted.

  FIG. 5 is a cross-sectional view illustrating an example of the liquid crystal display device 1 according to the present embodiment.

  The liquid crystal display device 1 according to the present embodiment includes a liquid crystal panel 7 having a configuration in which an array substrate 4 and a counter substrate 5 are opposed to each other via a liquid crystal layer 6, a light control element 31, and a backlight unit 30.

  The array substrate 4 includes a transparent substrate 8, a light shielding film 9, an insulating layer 10a, a plurality of light receiving elements 2a and 2b, an insulating layer 10b, common electrodes 11a to 11d, an insulating layer 10c, pixel electrodes 3a and 3b for image display, It includes light guide electrodes 3c and 3d for visible light control, transistors 12a and 12b for image display, and a transistor 12c for invisible light control.

  The light shielding film 9 is formed on one surface of the transparent substrate 8 such as glass.

  The insulating layer 10a is formed on the transparent substrate 8 on which the light shielding film 9 is formed. The light shielding film 9 is formed of, for example, the same metal thin film as the gate wiring or source wiring of the TFT.

  The light receiving elements 2a and 2b are formed on the insulating layer 10a. The light receiving element 2a detects the light that has passed through the red filter 14R provided in the pixel opening AP1 of the black matrix BM, but the light reflected in the liquid crystal panel 7 may also be detected by the light receiving element 2a. The light receiving element 2a is provided so as to overlap the pixel opening AP1 and the light shielding film 17 in a plan view and sandwiched between the pixel opening AP1 and the light shielding film 17 in the vertical direction of the cross section. The sensitivity region of the light receiving element 2a is, for example, a case where a wavelength region of 360 nm to 400 nm is used. As will be described below, the light receiving element 2a includes the wavelength and further has a main sensitivity region at the emission peak of the first light emitting elements 35a and 35b. desirable. For example, when the light emission peak wavelength of the second light emitting elements 35a and 35b is 385 nm, it is assumed that the light receiving element 2a has a light receiving sensitivity peak in the vicinity of 385 nm.

  For example, the red filter 14R included in the color filter layer 14 is formed to have a transmittance in the range of 24% to 55% at a wavelength of 385 nm. The red filter 14R has a main color material C.I. I. Pigment Red 254. The red filter is used for the toning. I. A yellow pigment or the like can be added to Pigment Red 254. The transmittance at a wavelength of 385 nm can be adjusted by the addition amount of a yellow pigment, which will be described in detail later, and the film thickness of the red filter 14R.

  As shown in FIG. 22, in the ultraviolet region including 385 nm and the infrared region from 700 nm to 800 nm (the range from 750 nm to 800 nm is not shown), C.I. I. Pigment Red 254 (hereinafter abbreviated as PR254) is C.I. I. The transmittance is higher than that of CI Pigment Blue 15: 6 (hereinafter referred to as PB15: 6). It can be understood that in the light receiving element for invisible light in this region, the red filter including PR254 has a higher light receiving sensitivity than the blue filter including PB15: 6. For example, at a light wavelength of 385 nm, the transmittance of a red filter using PR254 as a color material is 50%, whereas the transmittance of a blue filter using PB15: 6 as a color material is 23.5%. Has more than twice the transmittance. For example, at 750 nm, the transmittance of the red filter using PR254 as the color material is 96.5%, whereas the transmittance of the blue filter using PB15: 6 as the color material is 0.6%. It is.

  The light receiving element 2b can detect the light reflected in the liquid crystal panel 7. For example, the light detected by the light receiving element 2b includes reflected light from various interfaces on the counter substrate 5 side, reflected light from the interface between the counter substrate 5 and the liquid crystal layer 6, and the like. The light receiving element 2b overlaps with the frame portion BM1 of the black matrix BM and the light shielding film 9 in a plan view, and is provided in a state sandwiched between the frame portion BM1 of the black matrix BM and the light shielding film 9 in the vertical direction of the cross section. . The light receiving element 2b is a light receiving element for signal compensation.

  As the driving elements for the plurality of light receiving elements 2a and 2b, for example, two or more of gallium (Ga), indium (In), zinc (Zn), hafnium (Hf), tin (Sn), and yttrium (Y) are used. A transistor including a channel layer containing any metal oxide is used. As described above, the transistor may be a transistor using a polysilicon semiconductor as a channel layer.

  The light receiving elements 2a and 2b are provided for, for example, adjacent pixels or subpixels.

  The insulating layer 10b is formed on the plurality of light receiving elements 2a and 2b. The insulating layer 10b can also be used as a gate insulating film.

  The common electrodes 11a to 11d are formed on the insulating layer 10b.

  The pixel electrodes 3a and 3b for image display and the light guide electrodes 3c and 3d for invisible light control are formed on the insulating layer 10c.

  The image display transistors 12a and 12b are electrically connected to the image display pixel electrodes 3a and 3b.

  The invisible light control transistor 12c is electrically connected to the invisible light control light guide electrodes 3c and 3d.

  As the image display transistors 12a and 12b and the invisible light control transistor 12c, for example, a transistor having an oxide semiconductor as a channel layer is used.

  In the array substrate 3, the other surface side of the transparent substrate 8 is the back surface side of the liquid crystal panel 7, and the formation side of the pixel electrodes 3a, 3b and the light guide electrodes 3c, 3d is on the liquid crystal layer 6 side through an alignment film not shown. It becomes.

  The liquid crystal included in the liquid crystal layer 6 is assumed to have initial vertical alignment, for example. The liquid crystal display device 1 may be a VA liquid crystal system using liquid crystal with initial vertical alignment or an ECB system using liquid crystal with initial horizontal alignment. In the following, a liquid crystal having a negative dielectric anisotropy will be described as the VA liquid crystal, but a liquid crystal having a positive dielectric anisotropy may be used. As the VA liquid crystal, a liquid crystal having a positive dielectric anisotropy can also be used.

  For the liquid crystal layer 6, vertical alignment liquid crystal is used. Therefore, the alignment of the liquid crystal layer 6 is basically perpendicular to the substrate surface. The liquid crystal molecules L1 to L14 are aligned perpendicular to the surfaces of the counter substrate 5 and the array substrate 4. In the present embodiment, by generating an oblique electric field with respect to the substrate, alignment processing such as optical alignment and rubbing can be omitted for a vertical alignment film (not shown). In the present embodiment using an oblique electric field, strict pretilt angle control such as 89 degrees required in the conventional VA method is not necessary, and a liquid crystal with a simple initial vertical alignment such as 90 degrees is used. Can do.

  In the present embodiment, a liquid crystal material containing a fluorine atom in its molecular structure (hereinafter referred to as a fluorine-based liquid crystal) can be used as the liquid crystal material. Since the fluorine-based liquid crystal has a low dielectric constant, it can reduce the uptake of ionic impurities, can prevent performance deterioration such as a decrease in voltage holding ratio due to impurities, and suppress the occurrence of display unevenness. be able to.

  The polarizing plate not shown in FIG. 2 is cross black and normally black. It should be noted that normally white display can be used in applications where the contrast of the liquid crystal display is not important, for example, where touch sensing is important.

  The counter substrate 5 includes a transparent substrate 13, a black matrix BM, a color filter layer 14, a transparent resin layer (protective layer) 15, and counter electrodes 16a to 16d that are common electrodes. On one surface of the transparent substrate 13, a blue filter 14B, a red filter 14R, and a green filter 14G that are divided by a black matrix BM are formed. A transparent resin layer 15 is provided on the color filter layer 14 including the blue filter 14B, the red filter 14R, and the green filter 14G. On the transparent resin layer 15, counter electrodes 16a to 16d are formed. In the counter substrate 2, the other surface of the transparent substrate 13 (the upper side of the transparent substrate 22 in the drawing) is the observer side, and the counter electrodes 16a to 16d side are the liquid crystal layer 6 side through an alignment film (not shown). .

  The black matrix BM is formed on one surface of the transparent substrate 13 so as to form a plurality of pixel openings AP1 corresponding to a plurality of pixels or subpixels and partitioned in a matrix form in plan view. In the present embodiment, the black matrix BM includes, in units of pixels or sub-pixels, two parallel long sides of the frame portion BM1 that forms the pixel opening AP1 and a vertical direction that divides the pixel opening AP1 into two. The central part BM2 is provided. The central part BM2 may be omitted.

  In the present embodiment, the counter electrodes 16a to 16d of the counter substrate 13 shown in the cross section of FIG. 2 are arranged in line symmetry with respect to the central axis C of the subpixel.

  In the present embodiment, the pixel electrodes 3a and 3b, the light guide electrodes 3c and 3d, and the common electrodes 11a to 11d of the array substrate 4 shown in the cross section of FIG. 2 are symmetrical with respect to the central axis C of the subpixel. Be placed.

  The computing unit 17 calculates a value obtained by subtracting the observation value of the light receiving element 2b from the observation value of the light receiving element 2a as a compensated observation value (measured compensation value). In other words, the corrected observation value of the light receiving element 2a is obtained by subtracting the observation value of the light receiving element 2b from the observation value of the light receiving element 2a.

  In the present embodiment, two or more transistors 12a to 12c and a pixel electrode 3a, a pixel electrode 3b, and light guide electrodes 3c and 3d corresponding to each of the two or more transistors 12a to 12c are provided for the subpixel. It is done. More specifically, the transistors 12a and 12b have the liquid crystals L3 to L12 below the pixel aperture AP1 in order to control transmission of visible light for image display to be provided to the observer in a cross-sectional view. It is electrically connected to the pixel electrodes 3a and 3b to be driven. The transistor 12c is electrically connected to the light guide electrodes 3c and 3d that drive the liquid crystal molecules L1, L2, L13, and L14 in a cross-sectional view. In the present embodiment, the light guide electrodes 3c and 3d are driven by the common transistor 12c, but the light guide electrodes 3c and 3d may be driven by separate transistors.

  In FIG. 3, the display element scanning unit 18, the sensor scanning unit 19, the display element driving unit 20, and the sensor reading unit 21 are electrically connected to the liquid crystal panel 7. The backlight unit 30 including the light source is provided on the back side of the liquid crystal panel 7, but is omitted in FIG. The light emitting elements 32 a, 32 b, 35 a, 35 b such as LEDs of the backlight unit 30 are arranged on both sides of the liquid crystal panel 7, for example.

  In addition, as will be described in detail in an embodiment described later, as the installation form of the light emitting elements, for example, visible light emitting element arrays such as red, green, and blue are arranged at both ends of the backlight unit. Similarly, the light emitting element rows may be arranged at both ends of the backlight unit. The light emitting elements of such a backlight unit may be arranged at the upper end of the liquid crystal panel 7 and the lower end of the liquid crystal panel 7 in addition to the end portions on both sides of the liquid crystal panel 7.

  The visible light emitting elements arranged on the four sides of the liquid crystal panel 7 may be matched with the display contents by the local demming method, and the respective light emission intensities may be adjusted. Thereby, the contrast of the liquid crystal display can be improved.

  The second light emitting elements 32a and 32b have light emission timings and light emission intensities corresponding to images such as two-dimensional image display or three-dimensional image display, or corresponding to the local deming method as described above. The

  Thereby, the brightness and color of the liquid crystal display screen are different in different display portions depending on display contents. The intensity of visible light emitted from such a liquid crystal display screen varies greatly depending on the display portion, gradation display level, display timing, and the like.

  Therefore, it is desirable to avoid using visible light emitted from the liquid crystal display screen as illumination light for an input indicator such as a finger or a pointer. When an input indicator is detected using visible light with large fluctuations, it may be difficult to accurately detect the two-dimensional position of the input indicator, the height from the display surface, and the moving speed. . Also for detection of an input indicator using ambient light (external light) of a liquid crystal display device, high-precision detection may be difficult due to large fluctuations in ambient light.

  Therefore, in the present embodiment, the backlight unit 30 includes the first light emitting elements 35a and 35b in addition to the second light emitting elements 32a and 32b, and invisible light emitted from the first light emitting elements is used. The reflected light from the input indicator of invisible light emitted from the first light emitting element is detected by the light receiving element 2a that can receive light.

  Further, in the present embodiment, the synchronization control unit 36 sets the light emission timings 32a and 32b of the second light emitting elements to be different from the light emission timings of the first light emitting elements 35a and 35b, and the first light emitting elements 35a and 35b. Is synchronized with the light receiving timing of the light receiving element 2a to detect the input indicator with higher accuracy. Such a synchronization control unit 36 may be incorporated in the liquid crystal display device as a circuit, but may be controlled from the outside.

  The visibility of the human eye is reduced in a region with a wavelength shorter than 400 nm and a region with a wavelength longer than 700 nm, and invisible light is used in consideration of difficulty in visual recognition. Note that in consideration of the fact that the light conversion efficiency of a phototransistor in which a channel layer is formed of an oxide semiconductor, which will be described in detail later, increases at a wavelength shorter than 400 nm, a region having a wavelength shorter than 400 nm is used as the first light-emitting element. In the case of the invisible light emitted from, the upper limit of the wavelength of the short wavelength light having the short wavelength of the invisible light applied in the present embodiment is 400 nm.

Examples of the red material for the red filter 14R include C.I. which is an organic pigment. I. Pigment
Red 254 red pigment, C.I. I. A color material mixed with a yellow pigment such as Pigment Yellow 139 can be used. When giving priority to the transmittance of the red filter 14R, it is not necessary to add a yellow pigment. The red filter 14R using these pigments has a higher light transmittance in the wavelength range of 360 nm to 400 nm than the blue filter.

As shown in FIG. 22, at a wavelength of 385 nm, the red filter 14R can be given a transmittance that is at least twice that of the blue filter. The transmittance of the blue filter in FIG. 22 at a wavelength of 385 nm is about 24%. In the blue filter actually used, for example, C.I. I. Pigment
In Blue 15: 6, C.I. I. Since Pigment Violet 23 is added, the transmittance of the blue filter at a wavelength of 385 nm is often 20% or less. In addition, the light emitting elements 35a and 35b have high luminous efficiency on the longer wavelength side than 360 nm, and the power consumption of the liquid crystal display device 1 can be reduced.

  In this case, C.I. I. Pigment Red254, C.I. I. Pigment Yellow 139 with a weight ratio of 45:55 and a transmittance at 385 nm is 25% under the condition of a film thickness of 1 μm and a solid ratio, that is, a mass ratio of 37.5% of pigment to resin.

  Therefore, C.I. I. Pigment Red254 has 285 nm transmittance adjustment. I. Even if a yellow pigment such as Pigment Yellow 139 is blended at a high rate such as 55%, the transmittance peak of the blue pigment at 385 nm is exceeded, so it makes sense to provide the first light emitting element so as to overlap the red filter. is there.

  As the short wavelength light emitting elements 35a and 35b according to the present embodiment, an aluminum gallium nitride light emitting diode, a diamond light emitting diode, a zinc oxide light emitting diode, or a gallium nitride light emitting diode is used. Among gallium nitride diodes (hereinafter referred to as GaN blue light emitting diodes), InGaN light emitting diodes in which indium is added as a dopant to the active layer of the light emitting diodes are preferable. By adjusting the composition of In, the emission peak can be adjusted in the range of 360 nm to 420 nm. For example, an InGaN light emitting diode having an emission peak of 385 nm is commercially available in a small size chip that can be surface mounted.

  As the light receiving elements 2 and 2b according to the present embodiment, for example, as described above, among gallium (Ga), indium (In), zinc (Zn), hafnium (Hf), tin (Sn), and yttrium (Y). A phototransistor including a channel layer containing two or more metal oxides can be used. By forming impurity levels in the transparent channel layer of these composite metal oxides that are oxide semiconductors, the band gap can be reduced, and the sensitivity range of the light receiving elements 2 and 2b can be shifted to the longer wavelength side.

  The blue subpixel, the red subpixel, and the green subpixel shown in FIG. 1 include a display area 22 and a sensor area 23. In the present embodiment, the sub-pixel is the minimum display unit, but the pixel may be the minimum display unit. For example, a pixel may include at least one red subpixel, at least one blue subpixel, and at least one green subpixel.

  In the partial plan view of FIG. 1 and the partial cross-sectional view of FIG. 4, the light receiving elements 2a and 2b are shown. The light receiving elements 2 a and 2 b are provided in the sensor region 23. The sensor area 23 includes, for example, transistors or diodes that perform signal processing of the light receiving elements 2a and 2b, a calculation unit 17 that performs subtraction processing, and a signal line that distributes reset signals of the light receiving elements 2a and 2b. A plurality of transistors that perform signal processing may be provided in one pixel sensor region including a blue subpixel, a red subpixel, and a green subpixel. By applying a signal processing transistor or diode to the output values of the light receiving elements 2a and 2b, the output value can be processed quickly, and a high-speed input operation using the input indicator can be performed. The transistors 12a to 12c may be formed in the display region 22 or may be formed in the sensor region 23. The transistors 12a to 12c are electrically connected to a metal wiring such as a gate line and a source line (not shown).

As shown in FIG. 4, a blue filter 14B is disposed above the light receiving element 2a, and a light shielding film 9 is disposed below the light receiving element 2a. A black matrix BM is disposed above the light receiving element 2b, and a light shielding film 9 is disposed below the light receiving element 2b. By disposing the light receiving element 2b between the black matrix BM which is a light shielding pattern and the light shielding film 9, light is incident on the light receiving element 2b from the normal direction of the front surface of the liquid crystal display device 1, and the back surface of the liquid crystal panel 7 The direct incidence of light from the backlight unit 30 located in the light receiving element 2b is prevented. The light receiving element 2b is used to remove reflection noise generated in the liquid crystal cell in order to obtain an accurate received light value. The light receiving element 2b is used for signal compensation. The light shielding film 9 may be formed by the same process using the same material as the gate electrode.

  For example, in a configuration in which the metal wiring has copper or copper alloy as a surface layer, the light shielding film 9 and the gate electrode can be formed in a two-layer configuration of titanium alloy below the copper alloy layer.

  In particular, when the wavelength of the first light emitting element is 700 to 850 nm, the reflectance is higher than that of the conventional aluminum wiring, which is preferable.

  The display content of the liquid crystal display device 1 may cause a difference in brightness at the screen portion such as a bright display and a dark display, and may be uneven noise with respect to the light receiving element. In addition, the light from the backlight unit 30 is partially reflected at various interfaces such as the color filter layer 14 of the counter substrate 5, one surface of the transparent substrate 13, and a polarizing film, and is reflected on the light receiving elements 2 a and 2 b as reflected light. Incident. This reflected light becomes noise of received light intensity. The same applies to the case where an optical input device such as a light pen or laser light is used as the input indicator, and the re-reflected light becomes noise.

  In order to remove noise based on such reflected light or re-reflected light and obtain a highly accurate observation value, the calculation unit 18 subtracts the observation value of the light receiving element 2b from the observation value (light reception intensity) of the light receiving element 2a. To do. Thereby, noise compensation is realized. This signal compensation can also compensate for small variations in the observed values of the light receiving elements 2a and 2b using the oxide semiconductor as the channel layer, dark current, and noise generated based on the temperature, so that observation with extremely high accuracy is possible. A value can be obtained.

  It may not be preferable to perform a compensation calculation between light receiving elements having a difference in the display portion of the screen, such as bright display and dark display, because the amount of noise due to reflected light or re-reflected light differs greatly. The same applies to the case where a light input device such as a light pen or a laser beam is used, and the level of noise is greatly different between the light receiving element where light is irradiated and the light receiving element where light is not irradiated. Therefore, in this embodiment, the compensation calculation is performed by subtracting the observation values of the adjacent light receiving elements 2a and 2b.

  The switching unit 24 switches the intensity of the light emitted from the first light emitting element, for example, by changing the height of the voltage applied to the light guide electrodes 11c and 11d.

  When the compensation observation value obtained by the calculation unit 17 indicates that the input indicator has approached the liquid crystal display screen, the switching unit 24 applies a high voltage to the light guide electrodes 11c and 11d via the transistor 12c, The intensity of emission of light emitted from the first light emitting element can be increased automatically. By increasing the intensity of light emitted from the first light emitting element, the input indicator can be recognized even when the distance from the liquid crystal display screen to the input indicator is about 7 mm, for example. The 3D button display makes it easy to input with a click feeling.

  For example, the recognition of the input indicator is performed by setting two levels or a plurality of levels having different magnitudes to divide the compensation observation values after the compensation calculation by the calculation unit 17, and the number of compensation observation values belonging to each category (for example, This corresponds to the area of the finger on the liquid crystal display screen), or the change speed and position of the number of compensation observation values belonging to each category. By this detection, the distance and movement between the liquid crystal display screen and the input indicator can be recognized.

  For example, the switching unit 24 of the liquid crystal display device 1 may include an instruction receiving unit, and the liquid crystal display device 1 may display a switching request receiving unit on a screen and receive a switching instruction. The switching unit 24 switches the intensity of emission of light emitted from the first light emitting element according to the input switching instruction. For example, the switching unit 24 is a “display priority mode” that does not emit light emitted from the first light emitting element, and a “finger operation mode that emits light emitted from the first light emitting element and performs finger input. ”, Among the“ security modes ”for preventing third-party visibility, the mode designated by the observer is realized.

  When the “finger operation mode” is selected, the switching unit 24 emits light emitted from the first light emitting element having high intensity. As described above, the intensity of the light emitted from the first light emitting element is controlled based on the liquid crystal driving voltage applied to the light guide electrodes 3c and 3d. The “security mode” is used in a fourth embodiment having a slit opening to be described later.

  In this case, the switching unit and the calculation unit may be provided inside the liquid crystal display device, but may be those that perform control calculation from the outside.

  In the example of the B-B ′ cross section of FIG. 4, the counter electrodes 16 a to 16 d that are transparent conductive films are not stacked on the surface of the transparent resin layer 15 in contact with the liquid crystal layer 6 on the counter substrate 5 side. For example, the transparent conductive film (ITO) is generally formed using a mixed oxide of indium and tin. The refractive index of the color filter layer 14, the transparent resin layer 15, the transparent substrate 13, etc., which are members on the counter substrate 5 side, is in the range of about 1.5 to 1.6, whereas the refractive index of the transparent conductive film is 1.8 to 1.9. Accordingly, in the counter substrate 5, when a transparent conductive film such as the counter electrodes 16a to 16d is laminated on the transparent resin layer 15, the observation values of the reflected light from the transparent conductive film are added to the observation values of the light receiving elements 2a and 2b. The amount that is added increases.

  However, in this embodiment, since the transparent conductive film is not formed at the position of the counter substrate 5 facing the light receiving elements 2a and 2b, noise due to reflected light can be reduced. As in the present embodiment, the transparent conductive film using a material having a high refractive index has a lot of surface reflection, so that it is preferably formed only in a necessary portion of the display region 22.

  FIG. 5 is a cross-sectional view illustrating an example of the liquid crystal display device 1 according to the present embodiment. FIG. 5 illustrates an arrangement relationship among the liquid crystal panel 7, the light control element 31, and the backlight unit 30 provided in the liquid crystal display device 1.

  The backlight unit 30 includes light emitting elements 32 a, 32 b, 35 a, and 35 b such as LEDs on both sides of the back surface of the liquid crystal panel 7 or on the back surface of the liquid crystal panel 7. The light emitting element is configured by an LED array in which a plurality of first light emitting elements 35a and 35b and a plurality of second light emitting elements 32a and 32b are arranged.

  The light control element 31 is difficult to enter the eyes of the observer (user) and is installed between the back side of the liquid crystal panel 7 and the backlight unit 30 in order to prevent a third party from seeing the light. Give direction. The light control element 31 is generated using, for example, methacrylic resin. The light control element 31 has a configuration in which a prism sheet 33 and a lens sheet 34 are integrated back to back. In other words, the light control element 31 is a resin sheet in which the lens sheet 34 and the prism sheet 33 are integrated on the front and back.

  The prism sheet 33 has a plurality of triangular prisms arranged in the same direction so that the longitudinal direction (long direction, ridge line direction, or axial direction) of the side surfaces of the triangular prisms are parallel to each other. It is formed side by side so as to face.

  The lens sheet 34 is formed by arranging a plurality of semi-cylindrical lenses so that the longitudinal directions of the side surfaces of the semi-cylindrical lenses are parallel, and the semicircular arcs of the cross section face the same direction.

  By providing an angle θ1 between the longitudinal direction of the semi-cylindrical lens or the triangular prism and the pixel arrangement direction of the liquid crystal display device 1 in plan view, moire in three-dimensional image display can be reduced. As for the relaxation of moire, a better effect can be obtained as θ1 is closer to 45 degrees. However, when θ1 is 45 degrees, it may interfere with the polarizing plate or the optical axis of the phase difference, so θ1 is preferably set to an angle smaller than 45 degrees. Considering the alignment error (± 2 °) between the polarizing plate and the liquid crystal panel 7, the maximum value of the angle θ1 is preferably set to 43 degrees or less.

  In the three-dimensional image display, when θ1 is close to zero, a large moire of low frequency is conspicuous and it is easy to be visually recognized as light / dark or color unevenness. Therefore, in order to reduce the moire, it is preferable to make the angle θ1 between the longitudinal direction of the triangular prism and the pixel arrangement of the liquid crystal display device 1 larger than 3 degrees.

  The light emission angle (light distribution angle) with respect to the normal direction of the liquid crystal panel 7 can be set by the angle of the tip of the triangular prism having a cross-sectional shape of an isosceles triangle. In addition, as the light control element 31, two or more prism sheets having different angles θ1 may be used.

  For example, three-dimensional image display is realized by causing the second light emitting elements 32 a and 32 b of the backlight unit 30 to emit light alternately in synchronization with the liquid crystal operation of the liquid crystal display device 1.

  For example, the synchronization control unit 36 inputs the first light emitting elements 35a and 35b of the backlight unit 30 by causing them to emit light in synchronization with the light receiving elements 2a and 2b and the light guide electrodes 3c and 3d of the liquid crystal display device 1. Recognition of the indicator is realized.

  The backlight unit 30 may further include a diffusion plate, a light guide plate, a polarization separation film, a retroreflective polarizing element, and the like. A polarizing plate, a phase difference plate, or the like may be attached to the front and back of the liquid crystal panel 7.

  The backlight unit 30 may include, as the plurality of second light emitting elements 32a and 32b, for example, a plurality of white LEDs including three wavelengths of red, green, and blue in the emission wavelength region. As the second light emitting elements 32a and 32b, pseudo white LEDs in which a GaN blue LED and a YAG fluorescent material are combined may be used. In the case of using the pseudo white LED, in order to improve the color rendering, an LED having one or more main peaks such as a red LED may be used in combination. As the second light emitting elements 32a and 32b, for example, a light source in which a red LED and a green phosphor are combined with a blue LED may be used.

  Even without using the color filter layer 14, a light emitting element that individually emits red, green, and blue is used as a light source, and color display is realized by performing field sequential (time division) light emission in synchronization with liquid crystal drive. can do.

  The synchronization control unit 36 causes the second light emitting elements 32a and 32b at both ends of the backlight unit 30 to emit light alternately so as to be synchronized with the liquid crystal display, and causes light to enter the right eye and the left eye of the observer, respectively. Thereby, a three-dimensional image display is realized.

In addition, a liquid crystal driving voltage is simultaneously applied to the pixel electrodes 3a and 3b of the liquid crystal display device 1 and the above-described second light emitting elements 32a and 32b emit light at the same time, thereby displaying a bright two-dimensional image with a wide viewing angle. be able to. In this embodiment, it is possible to switch between 3D image display and 2D image display. Further, in the present embodiment, a great advantage can be obtained that a three-dimensional image can be displayed with high image quality in the two-dimensional image display without reducing the resolution of the three-dimensional image display.

  In the present embodiment, it is possible to suppress the observer who observes the display screen from being affected by the short wavelength light. By using the light control element 31 according to the present embodiment, high-quality three-dimensional image display can be realized.

  Hereinafter, liquid crystal driving by the counter substrate 5 and the array substrate 4 and light emitted by the liquid crystal driving will be described with reference to FIGS.

  FIG. 6 is a partial cross-sectional view showing an example of a state in which a liquid crystal driving voltage is applied only to the first pixel electrode 3a of the liquid crystal display device 1 according to the present embodiment.

  The liquid crystal molecules L1 to L14 of the liquid crystal display device 1 have negative dielectric anisotropy. The major axis direction of the liquid crystal molecules L1 to L14 is vertical before the drive voltage is applied, but when a voltage is applied to the pixel electrode 3a by the transistor 12a, some of the liquid crystal molecules L1 to L14 (in FIG. 6, the liquid crystal molecules L4 ~ L10) is inclined. FIG. 6 shows an example of the driving state of the liquid crystal when the driving voltage is applied only to the image electrode 3a.

  The liquid crystal molecules L4 to L9 are tilted in the direction perpendicular to the lines of electric force. The emitted light D1 passes through the inclined portion of the liquid crystal and is emitted, for example, in the direction of one eye (for example, the right eye) of the observer. The liquid crystal molecules L4 start to fall faster than other liquid crystal molecules by a strong electric field formed between the end of the pixel electrode 3a and the common electrode 11a. The operation of the liquid crystal molecules L4 serves as a trigger for the liquid crystal operation and enhances the response of the liquid crystal.

  FIG. 7 is a partial cross-sectional view illustrating an example of a state in which a liquid crystal driving voltage is applied only to the second pixel electrode 3b of the liquid crystal display device 1 according to the present embodiment.

  When a liquid crystal driving voltage is applied to the pixel electrode 3b by the transistor 12b, some of the liquid crystal molecules L1 to L14 (the liquid crystal molecules L5 to L11 in FIG. 7) are tilted in a direction perpendicular to the lines of electric force. The emitted light D2 passes through the inclined part of the liquid crystal and is emitted, for example, in the direction of the other eye (for example, the left eye) of the observer. The liquid crystal molecules L11 start to fall faster than other liquid crystal molecules by a strong electric field formed between the end of the pixel electrode 3b and the common electrode 11b. The operation of the liquid crystal molecules L11 serves as a trigger for the liquid crystal operation and improves the response of the liquid crystal.

  6 and 7 show operations of pixel electrodes and liquid crystal molecules for switching emitted light to the right eye and left eye necessary for three-dimensional image display. In the case of two-dimensional image display, the pixel electrodes 3a and 3b may be driven simultaneously. In a liquid crystal display device used only for two-dimensional image display, one transistor may be electrically connected to the pixel electrodes 3a and 3b instead of the two transistors 12a and 12b.

  FIG. 8 is a partial cross-sectional view showing an example of a state in which a liquid crystal driving voltage is applied to the light guide electrodes 3c and 3d of the liquid crystal display device 1 according to the present embodiment.

When a liquid crystal driving voltage is applied to the light guide electrodes 3c and 3d, the liquid crystal molecules L1 to L14 are tilted in a direction perpendicular to the lines of electric force. The invisible light D3 passes through the color filter layer 14 and a polarizing plate (not shown) and is emitted to the outside. Invisible light (for example, short wavelength light) D3 emitted from the first light emitting elements 35a and 35b illuminates an input indicator such as a finger, and the reflected light is received by the light receiving elements 2a and 2b. Then, by obtaining a compensated observation value obtained by subtracting the observation value of the light receiving element 2b from the observation value of the light receiving element 2a, the highly accurate and stable recognition of the input operation is realized.

  The synchronization control unit 36 synchronizes the sensing timing of the light receiving elements 2a and 2b and the light emission timing of the first light emitting elements 35a and 35b, thereby performing stable finger recognition during a finger operation on the liquid crystal display screen. Can do. The synchronization control unit 36 applies a liquid crystal driving voltage to the light guide electrodes 3c and 3d at the same timing as the sensing timing of the light receiving elements 2a and 2b, whereby the invisible light D3 is emitted from the liquid crystal screen.

  In the present embodiment described above, it is possible to remove the noise based on the reflected light in the liquid crystal panel 7 from the observation value by the light receiving element 2a, and obtain a highly accurate, uniform and stable compensated observation value, It is possible to recognize the operation by the input indicator with high accuracy. In the present embodiment, three-dimensional image display or two-dimensional image display can be performed. In this embodiment, by using invisible light, the visual sensitivity of the invisible light that illuminates the input indicator can be reduced, and the observer can observe visible light for image display.

  In the present embodiment, the pixel electrode 3a, the pixel electrode 3b, and the light guide electrodes 3c and 3d are formed separately and driven by different transistors 12a and 12b and a transistor 12c, respectively. In the present embodiment, the pixel electrode 3a, the pixel electrode 3b, and the light guide electrodes P21 and P24 can be electrically independent and different voltages can be applied, the drive voltage application timing to the pixel electrodes 3a and 3b, and the light receiving element There may be overlap with the drive voltage application timing to the light guide electrodes 3c and 3d for sensing 2a and 2b.

(Second Embodiment)
In the present embodiment, a liquid crystal display device in which a transistor is assigned to a pixel electrode in which a pixel electrode and a light guide electrode are integrated will be described.

  FIG. 9 is a partial cross-sectional view showing an example of a state in which a liquid crystal driving voltage is applied only to the first pixel electrode 38a of the liquid crystal display device 37 according to the present embodiment.

  The array substrate 39 of the liquid crystal display device 37 includes a pixel electrode 38a in which the pixel electrode 3a and the light guide electrode 3c of the first embodiment are integrated, and the pixel electrode 3b and the light guide electrode 3d of the first embodiment. A pixel electrode 38b having an integral structure is provided.

  The array substrate 39 of the liquid crystal display device 37 includes a common electrode 40a in which the common electrodes 11a and 11c are integrated, and a common electrode 40b in which the common electrodes 11b and 11d are integrated.

  The counter substrate 41 of the liquid crystal display device 37 includes a counter electrode 42a in which the counter electrodes 16a and 16c are integrated, and a counter electrode 42b in which the counter electrodes 16b and 16d are integrated.

  At the time of image display, the switching unit 43 can apply various drive voltages to the pixel electrodes 38a and 38b of the integrated structure using the transistors 12a and 12b in order to enable various image displays including gradation display. It is. During sensing of the light receiving elements 2a and 2b, invisible light from the first light emitting elements 35a and 35b is emitted at a constant intensity for photometry. At a timing used as the light guide electrode, a voltage having a substantially constant height is applied to the integrally configured pixel electrodes 38a and 38b. In the present embodiment, the transistors 12a and 12b apply a driving voltage for image display and a driving voltage for sensing the light receiving elements 2a and 2b at different timings.

Note that light for image display is visible light, short-wavelength light such as invisible light and ultraviolet light emitted from the first light emitting elements 35a and 35b, and long-wavelength light such as infrared light. Visible light emitted from the second light emitting elements 32a and 32b is emitted so as to enter the right eye of the observer, for example. At this time, the first light emitting elements 35a and 35b do not emit light, and no light is received by the light receiving elements 2a and 2b.

  FIG. 10 is a partial cross-sectional view showing an example of a state in which the liquid crystal driving voltage is applied only to the second pixel electrode 38b of the liquid crystal display device 1 according to the present embodiment. Visible light emitted from the second light emitting elements 32a and 32b is emitted so as to enter the left eye of the observer, for example. At this time, the first light emitting elements 35a and 35b do not emit light, and no light is received by the light receiving elements 2a and 2b.

  FIG. 11 is a partial cross-sectional view illustrating an example of a state in which a liquid crystal driving voltage is applied to both the pixel electrodes 38a and 38b of the liquid crystal display device 1 according to the present embodiment. Invisible illumination light (for example, near-ultraviolet light having a short wavelength of 385 nm to 400 nm) emitted from the first light emitting elements 35a and 35b is emitted, and reflected light from an input indicator such as a finger is incident on the light receiving element 2a. Incident light is input, and the position, size, moving direction, and the like of the input indicator are recognized. Application of a drive voltage for image display and application of a drive voltage for sensing the light receiving elements 2a and 2b are controlled in a time-sharing (field sequential) manner. The invisible illumination light for sensing the light receiving elements 2a and 2b is emitted light in a non-visible region with low visibility of the human eye, so that the image display quality is hardly deteriorated by the emission of the invisible light. Does not occur.

  In FIG. 11, when a driving voltage for displaying a two-dimensional image is applied (when sensing of the light receiving elements 2a and 2b is turned off), the liquid crystal molecules L1 to L14 operate as shown in FIG. Visible light is emitted from the second light emitting elements 32a and 32b. As shown in FIG. 11, the tilting of the liquid crystal molecules L1 to L14 is symmetric from the center of the subpixel and has an inclination gradient, so that a wide viewing angle which is not conventional can be obtained. As will be described later, for example, if the subpixel shape in plan view is a “<” shape, a wider viewing angle can be obtained in both the left and right and up and down directions of the liquid crystal display device 37. This wide viewing angle is also realized in this embodiment and other embodiments.

  The counter electrodes 42a, 42b shown in the present embodiment are deleted, and the configuration of the pixel electrodes 38a, 38b and the common electrodes 40a, 40b of the array substrate 39 is changed to IPS (horizontal electric field driving type liquid crystal). The present invention is also applied to a liquid crystal display device having a fringe field type electrode configuration composed of a fine comb-like pixel electrode and a solid common electrode provided via an insulating layer. A technique similar to that of the form can be applied. As described above, in this embodiment, the alignment direction and driving method of the liquid crystal are not limited.

(Third embodiment)
3rd Embodiment presupposes the liquid crystal display device provided with the backlight unit which comprises red light emitting LED, green light emitting LED, blue light emitting LED, and infrared light emitting LED as a light source, for example. The wavelength region in which the infrared light emitting LED can emit light may be in a range including 700 nm to 850 nm. When color display is not performed, a white light emitting LED or a fluorescent lamp may be used.

  In the present embodiment, it is assumed that the metal wiring for electrically connecting the transistors is a metal wiring having copper or a copper alloy as a surface layer. The “surface layer” refers to a metal layer on the liquid crystal layer side (photosensor side) in a sectional view of the array substrate. The lower metal layer is located on the transparent substrate side as the array substrate with respect to the surface layer copper or copper alloy. For the lower metal layer, a refractory metal such as titanium, molybdenum, tantalum, or tungsten, or an alloy thereof can be used. A copper alloy of the upper metal layer or a titanium alloy having an etching rate close to that of the upper metal layer can be selected as the metal layer of the lower gold. The film thickness of copper or a copper alloy and the metal film thickness of the lower metal layer can be set to, for example, 50 nm to 500 nm, respectively.

  These metal wirings can be at least two layers of metal wiring with copper or a copper alloy as a surface layer. A copper alloy in which one or more elements selected from magnesium, titanium, nickel, molybdenum, indium, tin, zinc, aluminum, calcium, and the like are added to copper can be employed. Although the element added to copper is not limited to these, it is preferable that the addition amount with respect to copper is 3 atomic percent or less with respect to the atomic percent of copper. If it is 1 atomic percent or less, the light reflectivity of the copper alloy is not greatly reduced. An addition amount of 1 atomic percent or less is more preferable.

  An array substrate that uses copper or a copper alloy as a metal wiring matches well with a transistor that uses an oxide semiconductor called IGZO or the like as a channel layer.

  For example, a metal film having a copper or copper alloy surface layer on an oxide semiconductor to be a channel layer can be selectively etched with an oxidizing alkali etchant to form a pattern as a metal wiring without damaging the oxide semiconductor. it can. It is possible to easily process a metal wiring and a metal layer having copper or a copper alloy as a surface layer, which has been difficult with a silicon semiconductor transistor.

  The reflectance of copper or copper alloy on the long wavelength side of light is high as shown in FIG. As shown in FIG. 23, re-reflected light can be used by arranging a metal film pattern and a metal wiring so as to fill the lower portions of the first light receiving element 2a and the second light receiving element 2b. The light receiving sensitivity of the light receiving elements 2a and 2b can be improved.

  In FIG. 23, the transistor including the oxide semiconductor channel layer 56 is illustrated as a bottom gate structure; however, the transistor is not necessarily specified as a bottom gate structure. For example, a transistor having a top gate structure, a double gate structure, or a dual gate structure can be employed.

  In the lower part of the light receiving element 2a shown in FIG. 23, a metal wiring 50 such as a source line or a drain line, or a dummy pattern 61 made of a metal layer is provided in a portion where the metal wiring 50 is not provided. For example, the dummy pattern 61 can be simultaneously formed in the same layer as the gate line 57 in the manufacturing process.

  Although not shown in FIG. 23, similarly to the lower part of the second light receiving element 2b, a metal wiring 50 such as a source line, a drain line, and a power supply line, or a dummy layer made of a metal layer in a portion where the metal wiring 50 is not provided. A pattern 61 is provided.

  Note that in FIG. 23, the source electrode and the drain electrode are illustrated as the electrode 60 of the transistor. The functions of the source electrode and the drain electrode can be interchanged depending on the connection relationship between the signal line and the power supply line of the transistor. In the present invention, such a source electrode, drain electrode, or gate electrode 57 is also included in the light-reflective metal wiring or metal layer, and is used as a light reflecting plate described later.

  The first light-receiving element 2a and the second light-receiving element 2b (not shown) are composed of a P-type semiconductor amorphous silicon 53, an intrinsic semiconductor (I-type) amorphous silicon 54, and an N-type semiconductor amorphous from the side closer to the liquid crystal layer 6. A laminated structure of silicon 55 is employed.

For example, a P-type semiconductor amorphous silicon 53 can be formed to a thickness of 5 to 50 nm, an I-type semiconductor amorphous silicon 54 can be formed to a thickness of 100 nm to 1000 nm, and an N-type semiconductor amorphous silicon 55 can be formed to a thickness of 20 nm to 200 nm. . On the upper surface of the amorphous silicon 53 of the P-type semiconductor and the lower surface of the amorphous silicon 55 of the N-type semiconductor, a light transmissive conductive film is disposed as the upper electrode 51 and the lower electrode 52, respectively. The conductive film can be formed of, for example, a conductive metal oxide called ITO.

  The upper electrode 51 can be, for example, a zigzag fine line pattern or a comb-like fine line pattern. By devising the pattern of the upper electrode 51, the current collection effect at the lower electrode 52 can be increased. In order to improve sensitivity on the light receiving elements 2a and 2b, for example, a columnar structure, unevenness, quantum dots, or the like may be laminated with a transparent resin or the like.

  You may add the particle | grains, dye, etc. which have a wavelength conversion function to these structures. The formation positions of the P-type semiconductor and the N-type semiconductor may be interchanged, or may be formed side by side in the horizontal direction. Amorphous silicon can be microcrystalline silicon.

  These light receiving elements 2a and 2b are formed, for example, using a known amorphous silicon semiconductor process on a substrate on which an oxide semiconductor transistor has been formed in advance as shown.

  The first light receiving element 2 a is electrically connected to the electrode 60 of any transistor from the lower electrode 52 through the contact hole 62 and the metal wiring 50. The upper electrodes 51 of the light receiving elements 2a and 2b are connected to a common electrode wiring through a contact hole (not shown).

  When the reset signal is given, the potentials of the light receiving elements 2a and 2b can be made a common potential. The insulating layers 10a, 10b, 10c, and 10d can be formed of, for example, silicon oxide, silicon oxynitride, aluminum oxide, a mixed oxide thereof, or a photosensitive and alkali developable acrylic resin. The second light receiving element 2b not shown in FIG. 2 is the same as the first light receiving element 2a.

  As shown in the drawing, a plurality of transistors can be provided below the light receiving elements 2a and 2b to drive the light receiving elements 2a and 2b. For example, a selection transistor, an amplification transistor, a reset transistor, a liquid crystal driving transistor, or the like of the light receiving elements 2a and 2b can be used as the plurality of transistors made of an oxide semiconductor. When the capacitances of the light receiving elements 2a and 2b are small, capacitors can be supplementarily arranged.

  As shown in FIG. 23, metal wiring having copper or a copper alloy as a surface layer or a dummy pattern made of a metal layer is formed so as to fill the lower portions of the light receiving elements 2a and 2b in plan view. Reflected light from a pointer such as a finger once enters the light receiving elements 2a and 2b. The transmitted light that has not been absorbed by the light receiving elements 2a and 2b is reflected by a metal wiring having copper or a copper alloy as a surface layer or a dummy pattern by the metal layer, and is incident again on the light receiving elements 2a and 2b. The effective sensitivity of the light receiving elements 2a and 2b can be improved by re-incidence of the transmitted light. A metal wiring having copper or a copper alloy as a surface layer or a dummy pattern made of a metal layer functions as a light reflecting plate for the light receiving elements 2a and 2b.

The transmittance R1 ′ of light of the red filter shown in FIG. 22 after the wavelength of 700 nm is a high transmittance of 90% or more, and as described above, reflection at a long wavelength of a metal having copper or a copper alloy as a surface layer. The rate is extremely high. By using a red filter and a metal having copper or a copper alloy as a surface layer as a light-reflecting reflector, the sensitivity of the light receiving element can be greatly improved.
(Fourth embodiment)
In this embodiment, a slit opening is formed in the black matrix BM, and a liquid crystal display device that emits visible light and ultraviolet light, for example, for preventing third-party visibility from the slit-like opening will be described. To do.

  In the present embodiment, a slit opening is provided to facilitate understanding of obliquely emitted light. However, for example, visible light may be emitted obliquely from the lower portion of the black matrix BM without providing the slit opening.

  In the present embodiment, for example, slit-shaped oblique light openings are formed on two parallel long sides of a black matrix that divides a pixel or sub-pixel having an outer shape in plan view. In the present embodiment, the oblique light includes invisible light and visible light. The oblique opening is an opening that emits near-ultraviolet light having a wavelength of, for example, 360 nm to 400 nm obliquely from the display surface when sensing the light receiving elements 2a and 2b, and emits visible light when used for security applications that prevent third-party viewing. The opening is emitted in an oblique direction.

  FIG. 12 is a partial plan view showing an example of the liquid crystal display device according to the present embodiment. FIG. 12 shows a planar view state (a state seen from the observer side) of the liquid crystal display device 44 according to the present embodiment.

  FIG. 13 is a partial cross-sectional view showing an example of the liquid crystal display device 44 according to the present embodiment. FIG. 13 is a cross-sectional view taken along the line CC ′ of FIG. 12, and the long side (side) of the frame portion BM1 of the black matrix BM provided in the liquid crystal display device 1 and the comb-like or striped pixel electrodes. A cross section perpendicular to the major axis direction is shown. In FIG. 13, the vertical alignment film, the polarizing plate, the retardation film, and the light receiving elements 2a and 2b shown in FIG. 12 are not shown. As will be described later, the liquid crystal display device 44 according to the present embodiment can switch between three-dimensional image display and normal two-dimensional image display.

  The array substrate 47 includes a transparent substrate 8, a light shielding film 9, an insulating layer 10a, a plurality of light receiving elements 2a and 2b, an insulating layer 10b, a common electrode 11, an insulating layer 10c, pixel electrodes 3a and 3b for image display, and oblique light control. Light guide electrodes 3c and 3d, image display transistors 12a and 12b, and oblique light control transistors 12c and 12d.

  The light shielding film 9 is formed on the one surface of the transparent substrate 8 such as glass by the same material and the same process as the metal wiring used for the gate line or the source line.

  The insulating layer 10a is formed on the transparent substrate 8 on which the light shielding film 9 is formed.

  The light receiving elements 2a and 2b are provided for adjacent pixels or sub-pixels. The plurality of light receiving elements 2a and 2b are formed on the insulating layer 10a.

  The light receiving element 2a detects light that has passed through the red filter 14R formed in the pixel opening AP1 of the black matrix BM, but the light reflected in the liquid crystal panel 45 may also be detected by the light receiving element 2a. The light receiving element 2a overlaps the red filter 14R in plan view. The light receiving element 2a has sensitivity in the near ultraviolet region having a wavelength of 360 nm to 400 nm.

  The light receiving element 2b detects the light reflected in the liquid crystal panel 45. For example, the light detected by the light receiving element 2 b includes reflected light from various interfaces on the counter substrate 46 side, reflected light from the interface between the counter substrate 46 and the liquid crystal layer 6, and the like. The light receiving element 2b overlaps with the green filter 14G and the light shielding film 9 in the pixel opening AP1 in plan view, and is provided between the green filter 14G or the black matrix BM1 and the light shielding film 17 in the vertical direction of the cross section. The light receiving element 2b is a light receiving element for signal compensation.

  The light receiving element 2b according to the present embodiment is disposed between the green filter 14G and the light shielding film 9. For example, since the transmittance of near-ultraviolet light in the vicinity of a wavelength of 385 nm of the green filter 14G of the green subpixel is low, in this embodiment, as described in the first embodiment, the light receiving element 2b is shielded from the black matrix BM. It is not necessary to arrange between the membrane 9. In particular, the transmittance of near-ultraviolet light in the vicinity of a wavelength of 385 nm of the green filter 14G containing a halogenated zinc phthalocyanine green pigment is lower than that of a halogenated copper phthalocyanine, and can be employed as a light shielding pattern for near-ultraviolet light. The transmittance of near-ultraviolet light in the vicinity of a wavelength of 385 nm when a yellow pigment is further added as a toning pigment to the green filter 14G is further reduced. In the present embodiment, the pixel aperture ratio of the blue subpixel, the pixel aperture ratio of the green subpixel, and the pixel aperture ratio of the red subpixel can be made uniform.

  The insulating layer 10b is formed on the insulating layer 10b on which the plurality of light receiving elements 2a and 2b are formed.

  The common electrode 11 is formed on the insulating layer 10b.

  The pixel electrodes 3a and 3b for image display and the light guide electrodes 3c and 3d for controlling oblique light are formed on the insulating layer 10c.

  The image display transistors 12a and 12b are electrically connected to the image display pixel electrodes 3a and 3b.

  The viewing angle control transistors 12c and 12d are electrically connected to the light guide electrodes 3c and 3d for oblique light control.

  As the image display transistors 12a and 12b and the oblique light control transistors 12c and 12d, for example, TFTs in which a transparent channel layer is formed of an oxide semiconductor are used.

  In the array substrate 47, the other surface side of the transparent substrate 8 is the back surface side of the liquid crystal panel 45, and the formation side of the pixel electrodes 3a, 3b and the light guide electrodes 3c, 3d is the liquid crystal layer 6 side.

  The liquid crystal included in the liquid crystal layer 6 is assumed to have initial vertical alignment, for example. The liquid crystal display device 44 may be a VA liquid crystal method using liquid crystal with initial vertical alignment or an ECB method using liquid crystal with initial horizontal alignment. In the following, a liquid crystal having a negative dielectric anisotropy will be described as the VA liquid crystal, but a liquid crystal having a positive dielectric anisotropy may be used. As the VA liquid crystal, a liquid crystal having a positive dielectric anisotropy can also be used.

  The counter substrate 46 includes a transparent substrate 8, a black matrix BM, a color filter layer 14, a transparent resin layer (protective layer) 7, and counter electrodes 16a to 16d.

  The black matrix BM is formed on one surface of the transparent substrate 13 so as to form a plurality of pixel openings AP1 corresponding to a plurality of pixels or subpixels and partitioned in a matrix form in plan view. Image display light provided to the observer is emitted from the plurality of pixel openings AP1.

  In the present embodiment, the black matrix BM includes, in units of pixels or sub-pixels, two parallel long sides of the frame portion BM1 that forms the pixel opening AP1 and a vertical direction that divides the pixel opening AP1 into two. The central part BM2 is provided. The central part BM2 may be omitted.

  Further, in the present embodiment, the black matrix BM includes oblique light openings AP2 formed in a slit shape on long sides facing each other in the horizontal direction in plan view. The oblique light aperture AP2 emits oblique light for the purpose of preventing third-party visibility and invisible light for sensing the light receiving element 2a.

  One of the blue filter 14B, the green filter 14G, and the red filter 14R is formed in each pixel opening AP1 formed by the black matrix BM on the transparent substrate 13. The color filter layer 14 includes a blue filter 14B, a green filter 14G, and a red filter 14R.

  A transparent resin layer 15 is formed on the transparent substrate 13 on which the black matrix BM and the color filter layer 14 are formed.

  The counter electrodes 16 a to 16 d are formed on the transparent resin layer 15.

  In the counter substrate 46, the other surface side of the transparent substrate 13 is an observer side, and the side on which the counter electrodes 16a to 16d are formed is the liquid crystal layer 6 side.

  In the present embodiment, the counter substrate 46 shown in the cross section of FIG. 13 has a line-symmetric configuration with respect to the central axis C of the subpixel.

  The pixel aperture AP1 of the polygonal subpixel is formed in a matrix. The planar shape of the pixel aperture AP1 is such that, for example, a square, a rectangle, a parallelogram, a polygon that is bent into a square shape (“<” or a boomerang shape), and the like are parallel to each other. Can be a simple polygon. In the counter substrate 46, a transparent slit-shaped oblique light aperture AP2 is formed in the center portion of the sides facing each other of the black matrix BM. In other words, on the side of the black matrix BM, a linear light shielding portion sandwiches the oblique light aperture AP2.

  As shown in FIG. 13, the oblique light aperture AP2 is preferably provided on both sides (left and right) of the sub-pixel for finger recognition and third-party visibility prevention. For example, in a plan view, even if oblique openings are provided above and below the vertical direction of the subpixel, and oblique light is emitted in the vertical direction, the effect of suppressing the viewing of a third party looking into the liquid crystal display screen from the side is small. The plan view shape of the oblique light aperture AP2 is not limited to the slit shape or the stripe shape, and may be a dot shape, an elliptical shape, a rectangular shape, or the like. The arrangement of the plurality of oblique light apertures AP2 may be asymmetrical or symmetric from the center of the subpixel in plan view. The oblique light aperture AP2 is preferably arranged along the longitudinal direction of the subpixel.

  In the present embodiment, the oblique light emission state from the oblique light aperture AP2 includes the shape or position of the light guide electrodes 3c and 3d, the common electrode 11, and the counter electrodes 16a to 16d for driving the liquid crystal, and the liquid crystal operation. is connected with. Therefore, the oblique light is efficiently emitted by adjusting the shape or position of the oblique light aperture AP2 according to the shape or position of the light guide electrodes 3c and 3d, the common electrode 11, and the counter electrodes 16a to 16d. Can do.

  Note that it is desirable that the oblique light emission direction is substantially orthogonal to the optical axis of the prism sheet (the ridge line direction of the prism sheet having a triangular cross section) included in the configuration of the light control element in the fourth embodiment described later. .

  The switching unit 24 switches the intensity of the oblique light emitted from the oblique light aperture AP2 by, for example, changing the height of the voltage applied to the light guide electrodes 3c and 3d.

  When the compensated observation value from the calculation unit 17 indicates that the finger has approached the liquid crystal display screen, the switching unit 24 applies a high voltage to the light guide electrodes 3c and 3d via the transistors 12c and 12d, and automatically In addition, the intensity of oblique light emission can be increased. By increasing the oblique light emission intensity, it becomes possible to recognize even if the distance from the liquid crystal display screen to the finger is about 7 mm, for example, and it becomes easy to input with a click feeling in the 3D button display on the liquid crystal screen. For example, in finger recognition, the compensation observation values obtained by performing the compensation calculation based on the observation values of the light receiving elements 2a and 2b are classified into two or more levels of different sizes, and The number of compensation observation values to which it belongs (e.g., corresponding to the area of the finger on the liquid crystal display screen) is obtained, or the change speed and the position of the number of compensation observation values corresponding to the respective sections are detected.

  Thereby, the distance and movement between the liquid crystal display screen and the input indicator such as a finger or a pointer can be recognized.

  For example, the switching unit 24 of the liquid crystal display device 44 may include an instruction receiving unit, and the liquid crystal display device 44 may display a switching request on a screen and receive a switching instruction. The switching unit 24 switches the emission state of the oblique light according to the input switching instruction.

  For example, the switching unit 24 is designated by the observer among a “display priority mode” that does not emit oblique light, a “finger operation mode” for performing finger input, and a “security mode” for preventing third-party viewing. Realize the mode. When the “security mode” is selected, the switching unit 24 emits intense light that is visible light. As described above, the intensity of the emitted light is controlled based on the liquid crystal driving voltage applied to the light guide electrodes 3c and 3d. When sensing the light receiving elements 2a and 2b, the invisible light emitting elements 35a and 35b are caused to emit light, and a driving voltage is applied to the light guide electrodes 3c and 3d at the observation timing of the light receiving elements 2a and 2b.

  Hereinafter, the operation of the liquid crystal by the counter substrate 46 and the array substrate 47 and the light emitted by this operation will be described with reference to FIGS.

  FIG. 14 is a partial cross-sectional view showing an example of a state in which the liquid crystal driving voltage is applied only to the first pixel electrode 3a of the liquid crystal display device 44 according to the present embodiment.

  The liquid crystal molecules L1 to L14 of the liquid crystal display device 44 have negative dielectric anisotropy. The major axis direction of the liquid crystal molecules L1 to L14 is vertical before the driving voltage is applied, but is inclined when a voltage is applied to any of the pixel electrodes 3a and 3b and the light guide electrodes 3c and 3d by the transistors 12a to 12d. . FIG. 14 shows an example of the driving state of the liquid crystal when the driving voltage is applied only to the image electrode 3a.

  The liquid crystal molecules L4 to L10 are tilted in the direction perpendicular to the lines of electric force. The emitted light D4 passes through the inclined portion of the liquid crystal and is emitted, for example, in the direction of one eye (right eye) of the observer. The liquid crystal molecules L4 start to fall faster than other liquid crystal molecules by a strong electric field formed between the end of the pixel electrode 3a and the common electrode 11. The operation of the liquid crystal molecules L24 serves as a trigger for the liquid crystal operation and improves the response of the liquid crystal.

  FIG. 15 is a partial cross-sectional view illustrating an example of a state in which a liquid crystal driving voltage is applied only to the second pixel electrode 3b of the liquid crystal display device 1 according to the present embodiment.

When a liquid crystal driving voltage is applied to the pixel electrode 3b, the liquid crystal molecules L5 to L11 are tilted in a direction perpendicular to the lines of electric force. The emitted light D5 passes through the inclined portion of the liquid crystal and is emitted, for example, in the direction of one eye (left eye) of the observer. The liquid crystal molecules L11 are connected to the end of the pixel electrode 3b and the common electrode 1.
It begins to fall faster than other liquid crystal molecules due to the strong electric field formed between them. The operation of the liquid crystal molecules L11 serves as a trigger for the liquid crystal operation and improves the response of the liquid crystal.

  FIG. 16 is a partial cross-sectional view illustrating an example of a state in which a liquid crystal driving voltage is applied only to the first light guide electrode 3c of the liquid crystal display device 1 according to the present embodiment.

  When a liquid crystal driving voltage is applied to the light guide electrode 3c, the liquid crystal molecules L1 to L3 are tilted in a direction perpendicular to the lines of electric force. The oblique light D6 is transmitted through the inclined liquid crystals L1 to L3 obliquely, passes through a polarizing plate (not shown), and is emitted to the outside as leakage light. In this case, although it is visually recognized as black display from the viewer direction, leakage light is observed by a third party in an oblique direction and is not visually recognized as black display. By applying a liquid crystal driving voltage to the light guide electrode 3c and emitting the oblique light D6, it is possible to prevent the third person around the observer from seeing. Furthermore, by emitting the oblique light D6, stable input by the light receiving element 2a can be performed, and stable finger recognition can be performed during finger operation on the liquid crystal screen.

  The amount of the leaked light and the angle of the oblique light D6 are as follows: the width W1 of the oblique light aperture AP2, the width W2 of the frame portion of the black matrix BM, and the interface from the one surface of the transparent substrate 13 to the liquid crystal layer 6 side. Can be controlled on the basis of the thickness Ht of the liquid crystal layer 6, the thickness Lt of the liquid crystal layer 6, the width W3 of the light shielding pattern 9, and the like.

  The liquid crystal molecules L3 start to fall faster than other liquid crystal molecules by a strong electric field formed between the end of the light guide electrode 3c and the common electrode 11. The operation of the liquid crystal molecules L3 serves as a trigger for the liquid crystal operation and enhances the response of the liquid crystal.

  FIG. 17 is a partial cross-sectional view illustrating an example of a state in which a liquid crystal driving voltage is applied only to the second light guide electrode 3d of the liquid crystal display device 1 according to the present embodiment.

  When a liquid crystal driving voltage is applied to the light guide electrode 3d, the liquid crystal molecules L12 to L14 are tilted in a direction perpendicular to the lines of electric force, and oblique light D7 is emitted. The liquid crystal molecules L12 start to fall faster than other liquid crystal molecules by a strong electric field formed between the end of the light guide electrode 3d and the common electrode 11. The operation of the liquid crystal molecules L12 serves as a trigger for the liquid crystal operation and improves the response of the liquid crystal. By applying a driving voltage to the light guide electrode 3d, the oblique light D7 is emitted, which hinders a third party around the observer from seeing. Note that the oblique light D6 in FIG. 16 and the oblique light D7 in FIG. 17 may be emitted simultaneously.

  In the present embodiment described above, the light receiving elements 2a and 2b can be formed in the liquid crystal panel 45 by forming the light receiving elements 2a and 2b from an oxide semiconductor.

  In the present embodiment, since the observation value detected by the light receiving element 2a can be compensated by the observation value detected by the light receiving element 2b, for example, finger input to the screen can be detected with high accuracy and stability. Can do.

  In the present embodiment, input detection can be performed on the liquid crystal display device 44 for displaying a three-dimensional image.

  In the present embodiment, it is possible to control the viewing angle by emitting oblique light D6 and D7, and to prevent the reflected light in the liquid crystal panel 45 from adversely affecting the observation value of the light receiving element 2a.

  In the present embodiment, by causing the second light emitting elements 32a and 32b of the backlight unit 30 to emit light in synchronization with the light guide electrodes 3c and 3d, visible light is emitted from the oblique opening AP2 and a third party. Visibility prevention is realized.

  In the present embodiment, it is possible to suppress the effective display area from being reduced, and it is possible to prevent the oblique lights D6 and D7 from being observed by the observer, so that the display quality can be maintained.

  In the present embodiment, the liquid crystal display device 44 can be prevented from becoming heavy and thick.

(Fifth embodiment)
In the present embodiment, a modification of the fourth embodiment will be described. The cross section of the oblique opening AP2 according to the present embodiment has a convex shape.

  FIG. 18 is a partial cross-sectional view showing an example of a liquid crystal display device according to this embodiment. FIG. 18 is a cross section perpendicular to the longitudinal direction of the comb-teeth of the comb-teeth or stripe-like electrode. FIG. 18 shows the alignment state of the liquid crystal molecules L1 to L16 between the counter substrate and the array substrate, and oblique light D3 and D4 emitted based on the operation of the liquid crystal molecules L1 to L16. A film, a polarizing plate, a retardation plate, a transistor, and a light receiving element are omitted. FIG. 18 shows an initial alignment state of the liquid crystal to which no liquid crystal driving voltage is applied.

  The liquid crystal display device 26 includes a liquid crystal panel 29 in which an array substrate 27 and a counter substrate 28 face each other with the liquid crystal layer 6 interposed therebetween. The liquid crystal display device 26 according to the present embodiment is characterized by a transparent pattern 48 provided in the oblique light aperture AP2. The thickness Ht in the vertical direction of the transparent pattern 48 is larger than the thickness in the vertical direction of the black matrix BM and the thickness of the color filter layer 14. The portion of the counter substrate 28 where the transparent pattern 48 is formed protrudes toward the liquid crystal layer 6 than other portions.

  Furthermore, a concave portion 49 is formed in the counter substrate 28 at the center of each subpixel.

  In the generation of the counter substrate 28, first, the black matrix BM and the transparent pattern 48 of the oblique light aperture AP2 are formed on the transparent substrate 13 such as glass. Next, the counter electrode 16 that is a transparent electrode is formed so as to cover the black matrix BM and the transparent pattern 48. A blue filter 14B, a green filter 14G, and a red filter 14R are stacked on the counter electrode 16 of each pixel opening AP1, and a transparent resin layer 15 is further formed as a protective layer.

  The array substrate 27 includes pixel electrodes 3e and 3f, a light guide electrode 3g, and common electrodes 11e, 11f, and 11g for each polygonal subpixel.

  A voltage for driving the liquid crystal is applied between the pixel electrodes 3e and 3f and the counter electrode 16, and between the pixel electrodes 3e and 3f and the common electrodes 11e and 11f. The array substrate 27 may not include the common electrodes 11e, 11f, and 11g. The pattern of the pixel electrodes 3e and 3f in plan view may be a comb-like pattern, a stripe pattern, or a pattern in which a plurality of slit-like openings are formed in a strip-like (solid) transparent conductive film.

  The emission angle θ of the oblique lights D6 and D7 can be controlled using the width W1 of the transparent pattern 48, the thickness H1 of the transparent pattern 48, the thickness Lt of the liquid crystal layer 6, the width W3 of the light shielding pattern 9, and the like.

  The pixel electrodes 3e and 3f and the light guide electrode 3g having a comb-teeth pattern and the common electrodes 11e, 11f and 11g having a comb-teeth pattern are arranged via an insulating layer 10c. At the position in the horizontal direction, the pixel electrodes 3e and 3f and the light guide electrode 3g are shifted from the common electrodes 11e, 11f and 11g. In FIG. 18, the pixel electrodes 3e, 3f and the light guide electrode 3g and the common electrodes 11e, 11f, 11g partially overlap and the other part protrudes in the horizontal direction. In the horizontal direction, the common electrodes 11e, 11f, and 11g are shifted to the transparent pattern 48 side (subpixel end side) with respect to the corresponding pixel electrodes 3e, 3f and the light guide electrode 3g.

  The comb-like pattern of the pixel electrodes 3e, 3f and the light guide electrode 3g and the common electrodes 11e, 11f, 11g is formed by electrically connecting two or more linear conductors having a width of 2 μm to 20 μm, for example. The connecting portion of the linear conductor may be formed only on one side or on both sides. The connecting portion is a peripheral portion of the polygonal sub-pixel, and is preferably disposed outside the pixel opening AP1 in plan view.

  The interval between the comb-like patterns is, for example, in the range of about 3 μm to 100 μm, and is selected based on the liquid crystal cell conditions and the liquid crystal material. The formation density, pitch, and electrode width of the comb-like pattern can be changed within the subpixel or within the pixel.

  The amount of protrusion W4 between the pixel electrodes 3e, 3f and the light guide electrode 3g in the horizontal direction and the common electrodes 11e, 11f, 11g can be variously adjusted according to dimensions such as the material of the liquid crystal 6, the driving conditions, and the liquid crystal cell thickness. As the width W4 of the protruding portion, a small amount such as any value from 1 μm to 6 μm is sufficient. The width W5 of the overlapping portion can be used as an auxiliary capacity for liquid crystal driving. The liquid crystal molecules L1, L3 to L7, L10 to L14, and L16 are aligned substantially perpendicular to the substrate surface.

  Depending on the size or purpose of use of the liquid crystal display device 26, the number of comb teeth in the opening width direction of the subpixels or pixels in the pixel electrodes 3e, 3f, the light guide electrode 3g, and the common electrodes 11e, 11f, 11g having a comb-like pattern , Density, and spacing can be adjusted as appropriate.

  In the present embodiment, a transparent conductive film as the counter electrode 16 is formed between the transparent substrate 13 and the color filter layer 14. In the present embodiment, in manufacturing the counter substrate 28, the color filter layer 14 is formed after the transparent conductive film. In the liquid crystal display device 26 including the counter substrate 28 having such a configuration, even if the light emitted from the backlight unit 30 is reflected at the interface of the counter electrode 16, the reflected light is transmitted through the color filter layer. 14 is absorbed. Therefore, in this embodiment, the light emitted from the backlight unit 30 installed on the back surface of the liquid crystal panel 29 is reflected by the interface of the counter electrode 16 of the liquid crystal panel 29 and is observed by the light receiving elements 2a and 2b. Can alleviate that.

  In the configuration of the counter electrode 15 in which the color filter layer 14 or the transparent resin layer 15 that is also a dielectric is stacked on the counter electrode 16 as in the present embodiment, it is applied between the pixel electrodes 3 e and 3 f and the counter electrode 16. The equipotential lines related to the liquid crystal driving voltage can be widened in the liquid crystal thickness direction, and the transmittance can be improved.

  In the present embodiment, the liquid crystal molecules L2 and L15 in the vicinity of the transparent pattern 15 of the counter substrate 28 and the liquid crystal molecules L8 and L9 in the vicinity of the concave portion 49 at the center of the counter substrate 28 are inclined by a predetermined angle in advance. Thereby, the liquid crystal molecules L1 to L16 can be effectively tilted when the drive voltage is applied.

The oblique lights D6 and D7 are one or both of visible light emitted from the second light emitting element and invisible light emitted from the first light emitting element. The synchronization control unit 36 applies liquid crystal driving voltage to the light guide electrode 3g and emits light of one or both of the second light emitting elements 32a and 32b and the first light emitting elements 35a and 35b in the oblique light emission. , Do it synchronously.

  The synchronization control unit 36 synchronizes the application of the liquid crystal driving voltage to the light guide electrode 3g, the light emission of the first light emitting elements 35a and 35b, and the light reception of the light receiving elements 2a and 2b when an input indicator such as a finger is recognized. To do. Switching between the three-dimensional image display and the two-dimensional image display is possible in the same manner as in the first embodiment. The application of the “finger operation mode” or the “security mode” is possible as in the third embodiment.

  In the present embodiment, the position where the transparent conductive film is formed in FIG. 18 is between the black matrix BM and the color filter layer 14, but the transparent conductive film such as between the transparent substrate 13 and the black matrix BM is It may be formed at another position.

(Sixth embodiment)
In the present embodiment, the relationship between the planar shape of the subpixel and the shape of the pixel electrode will be described.

  FIG. 19 is a plan view illustrating a first example of the relationship between the planar shape of the sub-pixel according to the present embodiment and the shapes of the pixel electrodes 3e and 3f and the light guide electrode 3g.

  In FIG. 19, the sub-pixel is a vertically long rectangle in plan view. The pixel electrodes 3e and 3f and the light guide electrode 3g, which are comb-shaped electrodes, are electrically connected to three different transistors, respectively.

  The light guide electrode 3g works with the corresponding common electrode 11g, drives the liquid crystal near the oblique light aperture AP2, and emits oblique light D6 and D7. In the case of the configuration of FIG. 19, the slit-shaped oblique light aperture AP2 is formed in parallel with the light guide electrode 3g in order to emit oblique light that passes through the liquid crystal driven by the light guide electrode 3g.

  In this embodiment, the connection part between the comb-tooth parts of the pixel electrodes 3e and 3f overlaps the lower side of the black matrix BM of the sub-pixels in plan view. The connection part between the comb-tooth parts of the light guide electrode 3g overlaps with the upper side of the black matrix BM of the subpixels in plan view. The number of comb teeth, the density, and the electrode width of the pixel electrodes 3e and 3f and the light guide electrode 3g can be variously changed according to the conditions of the liquid crystal cell.

  FIG. 20 is a plan view showing a second example of the relationship between the planar shape of the sub-pixel and the shapes of the pixel electrodes 3e and 3f and the light guide electrode 3g according to the present embodiment.

  FIG. 21 is a plan view showing a third example of the relationship between the planar shape of the sub-pixel and the shapes of the pixel electrodes 3e and 3f and the light guide electrode 3g according to the present embodiment.

  In FIG. 20, the subpixel is a parallelogram in plan view. In FIG. 21, the subpixel is a polygon having a “<” shape in a plan view. F1 to F4 are liquid crystal tilt directions when a liquid crystal driving voltage is applied to the pixel electrodes.

  Considering the emission directions of the oblique lights D6 and D7 used for viewing angle control, the planar shape of the subpixel is preferably a parallelogram or a polygon of a "<" shape.

When displaying characters on a liquid crystal display device, the visibility of third parties can be reduced over a wide range by applying parallelogram subpixels whose emission direction changes for each subpixel of the character display. Becomes easier.

  When two to four transistors are formed for one subpixel, and the pixel electrodes 3e and 3f for image display and the light guide electrode 3g for viewing angle control are divided and driven by each transistor, the pixel shape The contribution of the factor is slightly reduced. This is because when the pixel electrodes 3e and 3f for image display and the light guide electrode 3g for viewing angle control are divided and driven in this way, the oblique light is separated from the image display by the light guide electrode 3g for viewing angle control. This is because D6 and D7 can be controlled.

  Further, when the pixel electrodes 3e and 3f for image display and the light guide electrode 3g for controlling the viewing angle are divided and driven, the third light by the oblique lights D6 and D7 is used by using the light guiding electrode 3g for controlling the viewing angle. In order to further reduce the human visibility, the drive voltage signal may be randomized and the shape and arrangement of the transparent pattern 48 may be randomized.

  By forming 2 to 4 transistors for one subpixel, oblique light D6 and D7 can be individually emitted when necessary, and can be randomized to display characters on the display screen. It is possible to prevent third parties from seeing at a high level.

  Note that the synchronization control unit 36 emits visible light from the second light emitting elements 32a and 32b and applies voltage to the light guide electrode 3g with respect to oblique emission light for viewing angle control for the purpose of preventing third-party visibility. Are performed synchronously. When recognizing an input indicator such as a finger, the synchronization control unit 36 performs invisible light emission of the first light emitting elements 35a and 35b and voltage application to the light guide electrode 3g in synchronization.

  The light emission peaks of the first light emitting elements 35a and 35b can be set in the low visibility region of the human eye, and the light emission peaks of the second light emitting elements 32a and 32b are light emission peaks of blue, green and red which are visible light. Can be set.

  Since the light receiving elements 2a and 2b having a transparent channel layer formed of an oxide semiconductor can set sensitivity according to the peak wavelength in the non-visible wavelength region of the first light emitting element, in the present embodiment, as the oblique light Visible light and invisible light may be emitted simultaneously, or visible light and invisible light may be emitted in a time-sharing manner.

(Seventh embodiment)
In the present embodiment, examples of various materials such as transparent resins and organic pigments used in the counter substrates 5, 41, and 46 of the liquid crystal display devices 1, 37, and 44 according to the above-described embodiments will be described.

  The photosensitive coloring composition used for forming the color filter layer 14 contains, in addition to the pigment dispersion, a polyfunctional monomer, a photosensitive resin or a non-photosensitive resin, a polymerization initiator, a solvent, and the like. The highly transparent organic resins used in this embodiment, such as a photosensitive resin or a non-photosensitive resin, are collectively referred to as a transparent resin.

For the black matrix BM, the transparent resin layer 15, and the color filter layer 14, it is preferable to use a photosensitive resin composition that can be patterned by photolithography, or a transparent resin such as a thermosetting resin. The resin used for the black matrix BM and the color filter layer 14 is preferably a resin imparted with alkali solubility. The alkali-soluble resin may be a resin containing a carboxyl group or a hydroxyl group. For example, as the alkali-soluble resin, an epoxy acrylate resin, a novolac resin, a polyvinylphenol resin, an acrylic resin, a carboxyl group-containing epoxy resin, a carboxyl group-containing urethane resin, or the like is used. Among these, epoxy acrylate resins, novolak resins, and acrylic resins are preferable, and epoxy acrylate resins or novolak resins are particularly preferable.

  Examples of red pigments include C.I. I. Pigment Red254 is used as at least a main color material. Furthermore, a small amount of pigment can be added to this in terms of toning. Examples of red pigments include C.I. I. Pigment Red 7, 9, 14, 41, 48: 1, 48: 2, 48: 3, 48: 4, 81: 1, 81: 2, 81: 3, 97, 122, 123, 139, 146, 149, 168, 177, 178, 179, 180, 184, 185, 187, 192, 200, 202, 208, 210, 215, 216, 217, 220, 223, 224, 226, 227, 228, 240, 242, 246, 255, 264, 272, 279, etc. can be added.

  Examples of yellow pigments include C.I. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 10, 12, 13, 14, 15, 16, 17, 18, 20, 24, 31, 32, 34, 35, 35: 1, 36, 36: 1, 37, 37: 1, 40, 42, 43, 53, 55, 60, 61, 62, 63, 65, 73, 74, 77, 81, 83, 86, 93, 94, 95, 97, 98, 100, 101, 104, 106, 108, 109, 110, 113, 114, 115, 116, 117, 118, 119, 120, 123, 125, 126, 127, 128, 129, 137, 138, 139, 144, 146, 147, 148, 150, 151, 152, 153, 154, 155, 156, 161, 162, 164, 166, 167, 168, 169, 170, 171, 172, 1 73, 174, 175, 176, 177, 179, 180, 181, 182, 185, 187, 188, 193, 194, 199, 213, 214, etc. can be used.

  Examples of blue pigments include C.I. I. Pigment Blue 15, 15: 1, 15: 2, 15: 3, 15: 4, 15: 6, 16, 22, 60, 64, 80, etc., among which C.I. I. Pigment Blue 15: 6 is preferred.

  Examples of purple pigments include C.I. I. Pigment Violet 1, 19, 23, 27, 29, 30, 32, 37, 40, 42, 50 and the like can be used. I. Pigment Violet 23 is preferred.

  Examples of the green pigment used for the green filter 14G include C.I. I. Pigment Green 1, 2, 4, 7, 8, 10, 13, 14, 15, 17, 18, 19, 26, 36, 45, 48, 50, 51, 54, 55, 58, etc. can be used. Among these, C.I. is a halogenated zinc phthalocyanine green pigment. I. Pigment Green 58 is preferred. An aluminum halide phthalocyanine green pigment can also be used.

  A green filter using a halogenated zinc phthalocyanine green pigment has a lower dielectric constant than a green filter of a halogenated copper phthalocyanine that has been generally used as a green pigment. By using a zinc halide phthalocyanine green pigment for the green filter 14G, it is possible to substantially match the relative dielectric constant of the red filter 14R and the blue filter 14B included in the color filter layer 14.

For example, when the relative dielectric constant of each of the blue filter 14B of the blue subpixel and the red filter 14R of the red subpixel at a film thickness of 2.8 μm is measured at a liquid crystal drive frequency such as a voltage of 5 V, 120 Hz, and 240 Hz, the relative dielectric constant The rate falls in the range of approximately 3 to 3.9. Main coloring material of zinc halide phthalocyanine green pigment (Yellow pigment may be added as color adjustment)
The relative permittivity of the green filter 14G is approximately 3.4 to 3.7, and the relative permittivity of the green filter 14G is equal to the relative permittivity of the other two red filters 14R and blue filters 14B. Is possible.

  The arrangement of the relative dielectric constants of the blue filter 14B, the green filter 14G, and the red filter 14R is such that the color filter layer 14 is formed on the transparent electrode (common electrode 16) as shown in the fourteenth embodiment. Alternatively, in a horizontal electric field type liquid crystal display device called IPS, the effect is great. If the relative dielectric constants of the blue filter 14B, the green filter 14G, and the red filter 14R are the same level, adverse effects such as light leakage may be reduced due to different relative dielectric constants of the color filters when the liquid crystal is driven. it can.

  For example, the relative dielectric constant of the green filter 14G mainly composed of halogenated copper phthalocyanine is approximately 4.4 to 4.6, which is not much larger than the relative dielectric constants of the blue filter 14B and the red filter 14R. Further, the green filter 14G of a halogenated zinc phthalocyanine green pigment has a steep spectral characteristic curve and a higher transmittance than the green pigment of a halogenated copper phthalocyanine.

  As the light-shielding colorant used in the black matrix BM, a mixture of the above-mentioned various organic pigments can be used, or carbon excellent in light-shielding ability can be used.

  Each of the embodiments described above can be applied with various modifications within a range where the gist of the invention does not change.

  1, 26, 37, 44 ... liquid crystal display device, 2a, 2b ... light receiving element, BM ... black matrix, BM1 ... frame part, BM2 ... center part, 22 ... display area, 23 ... sensor area, 17 ... arithmetic part, AP1 ... pixel opening, AP2 ... oblique light opening, 3a, 3b, 3e, 3f, 38a, 38b ... pixel electrode, 3c, 3g ... light guide electrode, 4, 27, 39, 47 ... array substrate, 5, 28, 41, 46 ... counter substrate, 6 ... liquid crystal layer, 7, 29, 45 ... liquid crystal panel, 8, 13 ... transparent substrate, 9 ... light shielding pattern, 10a-10d ... insulating layer, 11, 11a-11g, 40a, 40b ... Common electrode, 12a to 12d ... transistor, 14 ... color filter layer, 14B ... blue filter, 14R ... red filter, 14G ... green filter, 15 ... transparent resin layer, 16a-16d, 42a, 42b ... counter electrode, DESCRIPTION OF SYMBOLS 1-L14 ... Liquid crystal molecule, 17 ... Operation part, 18 ... Display element scanning part, 19 ... Sensor scanning part, 20 ... Display element drive part, 21 ... Sensor reading part, 24, 43 ... Switching part, 30 ... Backlight unit 31 ... Light control element, 32a, 32b, 35a, 35b ... Light emitting element, 33 ... Prism sheet, 34 ... Lens sheet, 48 ... Transparent pattern, Metal wiring ... 50, Upper electrode ... 51, Lower electrode ... 52, Channel layer 56, transistor electrode 60, dummy pattern 61

Claims (7)

A liquid crystal display device comprising: a liquid crystal cell in which an array substrate and a counter substrate are bonded to face each other through a liquid crystal layer; and a backlight unit provided on the back side of the liquid crystal cell and including a light emitting element,
The light-emitting element includes a first light-emitting element that emits invisible light, and a second light-emitting element that emits visible light,
The counter substrate corresponds to a plurality of pixels or sub-pixels and forms a plurality of pixel openings divided in a matrix in plan view, and a red filter, a green filter, and a blue filter corresponding to the plurality of pixel openings. A color filter layer including a filter,
The array substrate has a first light receiving element having at least a non-visible light sensitivity region overlapping the red filter in a plan view, and the color filter layer having a low transmittance of the non-visible light emitted from the first light emitting element or A second light receiving element that overlaps the black matrix; a light guide electrode that drives a liquid crystal contained in a liquid crystal layer to emit the invisible light; and a liquid crystal in the liquid crystal layer that emits the visible light. A pixel electrode to be driven, and a transistor for driving one or both of the light guide electrode and the pixel electrode,
The red filter has a main colorant C.I. I. A liquid crystal display device, which is CI Pigment Red 254. The wavelength of invisible light emitted by the first light emitting element is in the range of 360 nm to 400 nm;
In addition, the color filter layer or the black matrix having a low transmittance of invisible light emitted from the first light emitting element on which the second light receiving element overlaps is the green filter or the black matrix. The liquid crystal display device according to claim 1. The wavelength of invisible light emitted by the first light emitting element is in the range of 700 nm to 850 nm;
In addition, the color filter layer or the black matrix having a low transmittance of invisible light emitted from the first light emitting element on which the second light receiving element overlaps, the green filter, the blue filter, or the black 2. The liquid crystal display device according to claim 1, wherein the liquid crystal display device is a matrix. The liquid crystal display device according to any one of claims 1 to 3,
The transistor is disposed below the light receiving element,
The metal wiring of the transistor has a two-layer structure of a metal layer made of copper or a copper alloy and a lower metal layer as viewed from the liquid crystal layer side, and two or more kinds of metals of gallium, indium, zinc, tin, and yttrium A liquid crystal display device comprising a channel layer containing an oxide. The liquid crystal display device according to any one of claims 1 to 4,
The light guide electrode further drives the liquid crystal contained in the liquid crystal layer for emission of the invisible light or the visible light,
The light emission timing of the second light-emitting element and the plurality of electrodes are synchronized with the light emission timing of the first light-emitting element and the liquid crystal driving voltage application timing of the light guide electrode. Further comprising a control means for synchronizing the liquid crystal driving voltage application timing.
A liquid crystal display device characterized by the above. The liquid crystal display device according to any one of claims 1 to 5,
The black matrix comprises oblique light openings formed on two sides facing each other in plan view,
The pixel electrode is for driving a liquid crystal corresponding to the pixel opening, and the light guide electrode is for driving a liquid crystal corresponding to the oblique light opening. Liquid crystal display device. The liquid crystal display device according to any one of claims 1 to 6,
The liquid crystal display device, wherein the liquid crystal layer includes liquid crystal with initial vertical alignment.

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