JP2013171271A - Liquid crystal display device, manufacturing method thereof, and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal display device etc. which can improve display image quality.SOLUTION: The liquid crystal display device comprises: a first substrate; a second substrate which comprises a color filter layer provided for each of a plurality of pixels, and a plurality of photoelectric conversion elements provided in regions between the pixels; and a liquid crystal layer provided between the first substrate and the second substrate. Each of the photoelectric conversion elements comprises: a photoelectric conversion layer; a transparent electrode provided on one side of the photoelectric conversion layer; and a light-shielding electrode provided on the other side of the photoelectric conversion layer.

Description

  The present disclosure relates to a liquid crystal display device having a photoelectric conversion element, a manufacturing method thereof, and an electronic apparatus including such a liquid crystal display device.

  2. Description of the Related Art Conventionally, various types of display devices incorporating a photoelectric conversion element (photodiode) have been proposed. For example, Patent Document 1 describes a liquid crystal display device in which a photoelectric conversion element is formed in an inter-pixel region.

  In this liquid crystal display device, the battery is charged using backlight light (internal light) or ambient light (external light) detected by the photoelectric conversion element, thereby achieving low power consumption and energy saving. Yes. In Patent Document 1, the photoelectric conversion element formed in the inter-pixel region also functions as a so-called black matrix layer (light shielding portion).

JP 2000-19983 A

  By the way, in general, various liquid crystal display devices have been proposed as methods for improving display image quality, and further improvement methods are desired. Therefore, an improvement in display image quality is also required for a liquid crystal display device incorporating a photoelectric conversion element as described above.

  The present disclosure has been made in view of such problems, and an object thereof is to provide a liquid crystal display device capable of improving display image quality, a manufacturing method thereof, and an electronic apparatus.

  A liquid crystal display device according to the present disclosure includes a first substrate, a second substrate having a color filter layer disposed for each of a plurality of pixels, and a plurality of photoelectric conversion elements disposed in an inter-pixel region; A liquid crystal layer provided between the substrate and the second substrate is provided. The photoelectric conversion element has a photoelectric conversion layer, a transparent electrode provided on one side of the photoelectric conversion layer, and a light-shielding electrode provided on the other side of the photoelectric conversion layer.

  An electronic apparatus according to the present disclosure includes the liquid crystal display device according to the present disclosure.

  A method of manufacturing a liquid crystal display device according to the present disclosure includes a step of forming a first substrate, a color filter layer disposed for each of a plurality of pixels, and a plurality of photoelectric conversion elements disposed in a region between pixels. The method includes a step of forming a second substrate and a step of forming a liquid crystal layer between the first substrate and the second substrate. In the step of forming the second substrate, a photoelectric conversion element is formed by the photoelectric conversion layer, the transparent electrode provided on one side of the photoelectric conversion layer, and the light-shielding electrode provided on the other side of the photoelectric conversion layer. .

  In the liquid crystal display device, the manufacturing method thereof, and the electronic device of the present disclosure, in the photoelectric conversion element disposed in the inter-pixel region, one side of the photoelectric conversion layer is a transparent electrode and the other side is a light shielding electrode. As a result, the light shielding electrode functions as a so-called black matrix portion while allowing light to enter from the transparent electrode side of the photoelectric conversion element, thereby improving the contrast during video display. In addition, for example, unlike the case where the photoelectric conversion layer itself functions as a black matrix portion after both sides of the photoelectric conversion layer are formed as transparent electrodes, the occurrence of a colored phenomenon in the black matrix portion is avoided.

  According to the liquid crystal display device, the manufacturing method thereof, and the electronic device of the present disclosure, in the photoelectric conversion element disposed in the inter-pixel region, one side of the photoelectric conversion layer is a transparent electrode and the other side is a light shielding electrode. In addition, it is possible to prevent the occurrence of a coloring phenomenon in the black matrix portion while making the light shielding electrode function as a black matrix portion to improve the contrast when displaying an image. Therefore, it is possible to improve the display image quality when displaying an image.

It is a schematic cross section showing an example of composition of a liquid crystal display concerning an embodiment of this indication. It is a schematic cross section showing one process in the manufacturing method of the liquid crystal display device shown in FIG. FIG. 3 is a schematic cross-sectional view illustrating a process following FIG. 2. 6 is a schematic cross-sectional view illustrating a configuration example of a liquid crystal display device according to Comparative Example 1. FIG. 10 is a schematic cross-sectional view illustrating a configuration example of a liquid crystal display device according to Comparative Example 2. FIG. It is a schematic cross section for demonstrating the effect | action of the liquid crystal display device shown in FIG. 10 is a schematic cross-sectional view illustrating a configuration example of a liquid crystal display device according to Modification 1. FIG. 10 is a schematic cross-sectional view illustrating a configuration example of a liquid crystal display device according to Modification 2. FIG. 10 is a schematic cross-sectional view illustrating a configuration example of a liquid crystal display device according to Modification 3. FIG. 10 is a schematic cross-sectional view illustrating a configuration example of a liquid crystal display device according to Modification 4. FIG. It is a perspective view showing the external appearance seen from the (A) front side in the application example 1 of the liquid crystal display device which concerns on embodiment and each modification, and the external appearance seen from the (B) back side. (A) is a perspective view showing the external appearance seen from the front side of the application example 2, (B) is a perspective view showing the external appearance seen from the back side. 12 is a perspective view illustrating an appearance of application example 3. FIG. 14 is a perspective view illustrating an appearance of application example 4. FIG. (A) is a front view of the application example 5 in an open state, (B) is a side view thereof, (C) is a front view in a closed state, (D) is a left side view, and (E) is a right side view, (F) is a top view and (G) is a bottom view.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. The description will be given in the following order.

1. Embodiment (an example in which a light-shielding electrode of a photoelectric conversion element is provided on the front side in a CF substrate)
2. Modified example Modified example 1 (example in which the transparent electrode of the photoelectric conversion element also serves as the common electrode of the liquid crystal element)
Modification 2 (Example of a reflective liquid crystal display device)
Modifications 3 and 4 (example in which a light-shielding electrode of a photoelectric conversion element is provided on the back side in the CF substrate)
3. Application examples (application examples of liquid crystal display devices to electronic devices)
4). Other variations

<Embodiment>
[Configuration of Liquid Crystal Display Device 1]
FIG. 1 schematically illustrates a cross-sectional configuration of a liquid crystal display device (liquid crystal display device 1) according to an embodiment of the present disclosure, together with a functional block configuration. The liquid crystal display device 1 includes a backlight 10, a TFT (Thin Film Transistor) substrate 11, a liquid crystal layer 13, and a CF (Color Filter) from the back (back) side to the front (observation surface, display surface) side. The substrate 12 is provided in this order. That is, in the liquid crystal display device 1, the TFT 11 is disposed on the back side, and the CF substrate 12 is disposed on the front side. The liquid crystal display device 1 also includes a charging unit 15 and a device driving unit 16 shown in the functional block configuration.

  Here, the backlight 10 corresponds to a specific example of “light source unit” in the present disclosure, the TFT substrate 11 corresponds to a specific example of “first substrate” in the present disclosure, and the CF substrate 12 corresponds to “ This corresponds to a specific example of “second substrate”. The charging unit 15 corresponds to a specific example of “first charging unit” in the present disclosure.

(Backlight 10)
The backlight 10 is disposed on the back side of the TFT substrate 11 and irradiates (emits) light (light source light) toward the liquid crystal display panel (TFT substrate 11, liquid crystal layer 13 and CF substrate 12). is there. Such a backlight 10 includes, for example, a light source such as a CCFL (Cold Cathode Fluorescent Lamp) or an LED (Light Emitting Diode) and various optical sheets ( Neither is shown).

  The liquid crystal display panel in which the TFT substrate 11, the liquid crystal layer 13, and the CF substrate 12 are stacked is a display panel having a plurality of pixels (red pixels 14R, green pixels 14G, and blue pixels 14B), and each pixel will be described later. A liquid crystal element is formed.

(TFT substrate 11)
The TFT substrate 11 is a substrate having optical transparency, and includes an element formation substrate 110 and a plurality of pixel electrodes 111. For example, the element forming substrate 110 is formed by forming driving elements such as TFTs and wiring (not shown) on a transparent substrate such as a glass substrate. The pixel electrode 111 is individually disposed for each of the plurality of pixels (the red pixel 14R, the green pixel 14G, and the blue pixel 14B) on the element formation substrate 110 (the liquid crystal layer 13 side). The pixel electrode 111 is a transparent electrode configured using, for example, ITO (Indium Tin Oxide).

(CF substrate 12)
The CF substrate 12 is also a light-transmitting substrate, and includes a counter substrate 120, a color filter layer 121, a common electrode 122 (counter electrode), and a plurality of photodiodes 123. The counter substrate 120 is configured using, for example, a transparent substrate such as a glass substrate.

  The color filter layer 121 is disposed on the counter substrate 120 (the liquid crystal layer 13 side). The color filter layer 121 includes a plurality of color filters (CF) arranged separately for each of the plurality of pixels (red pixel 14R, green pixel 14G, and blue pixel 14B). Specifically, a red color filter 121R that selectively transmits red light is disposed in the red pixel 14R, and a green color filter 121G that selectively transmits green light is disposed in the green pixel 14G. A blue color filter 121B that selectively transmits blue light is disposed in the pixel 14B. Each of the red color filter 121R, the green color filter 121G, and the blue color filter 121B is configured using, for example, a predetermined resin material.

  The common electrode 122 is formed on the color filter layer 121 (on the liquid crystal layer 13 side) in common for each pixel (red pixel 14R, green pixel 14G, and blue pixel 14B) (uniformly formed in the CF substrate 12). Electrode. The common electrode 122 is also a transparent electrode formed using, for example, ITO. A liquid crystal element is formed for each pixel by the common electrode 122, the pixel electrode 111 described above, and the liquid crystal layer 13 described later. That is, it can be said that the common electrode 122 is an electrode common to a plurality of liquid crystal elements.

(Photodiode 123)
The photodiode 123 is a photoelectric conversion element that generates a charge (photocharge) having a charge amount corresponding to the amount of incident light (received light amount) and accumulates the charge therein, for example, a PIN (Positive Intrinsic Negative Diode) type photodiode. Consists of. In the photodiode 123, the sensitivity range is, for example, the visible range (the light reception wavelength band is the visible range). The photodiode 123 is an area between the plurality of pixels (the red pixel 14R, the green pixel 14G, and the blue pixel 14B) described above (in the same layer as the color fill layer 121) between the counter substrate 120 and the common electrode 122. It is selectively disposed in the inter-pixel region.

  Specifically, the photodiode 123 has a light shielding electrode 123S (upper electrode), an n-type semiconductor layer 123N, an i-type semiconductor layer 123I, a p-type semiconductor layer 123P, and a transparent electrode 123T in the inter-pixel region on the counter substrate 120. (Lower electrode) are laminated in this order. In other words, the photodiode 123 includes the transparent electrode 123T from the film surface side (back side, liquid crystal layer 13 side) in the CF substrate 12 toward the counter substrate 120 side (front side, opposite to the liquid crystal layer 13). The p-type semiconductor layer 123P, the i-type semiconductor layer 123I, the n-type semiconductor layer 123N, and the light shielding electrode 123S are stacked in this order.

  Among these, the p-type semiconductor layer 123P, the i-type semiconductor layer 123I, and the n-type semiconductor layer 123N correspond to a specific example of “a photoelectric conversion layer” in the present disclosure. In this example, the p-type semiconductor layer 123P is provided on the film surface side (lower side) of the CF substrate and the n-type semiconductor layer 123N is provided on the counter substrate 120 side (upper side). That is, a stacked structure in which the lower side is an n-type semiconductor layer and the upper side is a p-type semiconductor layer may be used.

The transparent electrode 123T is one electrode for reading (extracting) signal charges from the photoelectric conversion layer (n-type semiconductor layer 123N, i-type semiconductor layer 123I, p-type semiconductor layer 123P). The transparent electrode 123T is made of, for example, a transparent conductive material such as ITO, IZO (Indium Zinc Oxide), SnO ₂ (tin oxide), ZnO ₂ (zinc oxide). Light).

  The n-type semiconductor layer 123N is made of, for example, amorphous silicon (amorphous silicon: a-Si) doped with phosphorus (P), and forms an n-type region. The thickness of this n-type semiconductor layer 123N is, for example, about 10 nm to 50 nm.

  The i-type semiconductor layer 123I is an intrinsic semiconductor layer having lower conductivity than the n-type semiconductor layer 123N and the p-type semiconductor layer 123P, and is made of, for example, non-doped amorphous silicon (a-Si). The thickness of the i-type semiconductor layer 123I is, for example, about 400 nm to 1000 nm. The greater the thickness, the higher the photosensitivity.

  The p-type semiconductor layer 123P is made of, for example, amorphous silicon (a-Si) doped with boron (B) and forms a p-type region. The thickness of the p-type semiconductor layer 123P is, for example, about 10 nm to 50 nm.

  The light shielding electrode 123S is the other electrode for reading (extracting) signal charges from the photoelectric conversion layers (n-type semiconductor layer 123N, i-type semiconductor layer 123I, and p-type semiconductor layer 123P) described above. The light shielding electrode 123S is made of, for example, a light shielding conductive material such as chromium (Cr), molybdenum (Mo), aluminum (Al), titanium (Ti), nickel (Ni), or an alloy material mainly composed of these elements. It is configured by using light shielding properties. Moreover, either a single layer structure using these materials or a laminated structure in which a plurality of materials are combined may be used.

  Thus, in the photodiode 123, one side (here, the back side) of the photoelectric conversion layer (n-type semiconductor layer 123N, i-type semiconductor layer 123I, p-type semiconductor layer 123P) is the transparent electrode 123T and the other side ( Here, the light shielding electrode 123S is provided on the front side. As will be described in detail later, the light shielding electrode 123S in the photodiode 123 functions as a so-called black matrix (BM) portion that is a light shielding portion in the inter-pixel region.

(Liquid crystal layer 13)
The liquid crystal layer 13 is inserted (enclosed) between the TFT substrate 11 and the CF substrate 12 and can be configured using various liquid crystal materials. Further, it is possible to configure using various modes of liquid crystal such as a TN (Twisted Nematic) mode and a VA (Vertical Alignment) mode.

  In the liquid crystal display panel configured as described above, for example, the TFT substrate 11 and the CF substrate 12 are each provided with a polarizing plate (not shown) having a predetermined transmission axis and absorption axis. This polarizing plate is an optical element having a function of selectively transmitting a specific polarization component of incident light and absorbing other polarization components. In this case, the polarizing plate in the TFT substrate 11 and the polarizing plate in the CF substrate 12 are arranged so that their transmission axes are orthogonal to each other (crossed Nicols arrangement), or their transmission axes are parallel to each other. (Parallel Nicol arrangement).

(Charging unit 15, device driving unit 16)
The charging unit 15 emits light from the backlight 10 and enters the photodiode 123 through the liquid crystal layer 13 and the like (TFT substrate 11, liquid crystal layer 13, common electrode 122, and color filter layer 121) (backlight light). Based on the above, a predetermined charging operation is performed. Specifically, a charging operation to a battery (secondary battery) (not shown) is performed based on the backlight light incident on the photodiode 123 from the transparent electrode 123T side in this way.

  The device drive unit 16 drives a load in a predetermined device (such as an electronic device in which the liquid crystal display device 1 is built) using the electric power in the battery stored by charging by the charging unit 15 or the like.

[Method of Manufacturing Liquid Crystal Display Device 1]
The liquid crystal display device 1 can be manufactured as follows, for example. 2 and 3 are schematic cross-sectional views showing an example of a method for manufacturing the liquid crystal display device 1 in the order of steps.

  First, a liquid crystal display panel including the above-described TFT substrate 11, CF substrate 12, and liquid crystal layer 13 is manufactured. Specifically, as shown in FIG. 2A, first, an element formation substrate 110 is formed on a transparent substrate such as a glass substrate by using a known thin film process to form driving elements such as TFTs and wiring. Form. Subsequently, a plurality of pixel electrodes 111 made of the above-described material are formed on the element formation substrate 110 using a known thin film process. Thereby, the TFT substrate 11 is formed.

  Next, as shown in FIG. 2B, a plurality of photodiodes 123 having the above-described structure (here, PIN type) are formed in a region between pixels on the counter substrate 120 using a known thin film process. To do. That is, the photoelectric conversion layer (n-type semiconductor layer 123N, i-type semiconductor layer 123I and p-type semiconductor layer 123P), the transparent electrode 123T provided on one side (here, the back side) of the photoelectric conversion layer, and the other side A photodiode 123 is formed by the light shielding electrode 123S provided on the front side (here, the front side).

  Next, the color filter layer 121 is formed in the pixel region on the counter substrate 120 by color-coding for each of the plurality of pixels (the red pixel 14R, the green pixel 14G, and the blue pixel 14B) using, for example, a photolithography method. To do. That is, the red color filter 121R is formed in the red pixel 14R, the green color filter 121G is formed in the green pixel 14G, and the blue color filter 121B is formed in the blue pixel 14B.

  After that, the common electrode 122 made of the above-described material is formed on the color filter layer 121 using a known thin film process. Thereby, the CF substrate 12 is formed.

  Next, as shown in FIG. 3, liquid crystal is injected between the TFT substrate 11 and the CF substrate 12 formed in this way, thereby forming a liquid crystal layer 13. In this way, a liquid crystal display panel composed of the TFT substrate 11, the CF substrate 12, and the liquid crystal layer 13 is completed.

  Subsequently, when the backlight 10 is arranged on the back side of the liquid crystal display panel (TFT substrate 11). Further, the members (semiconductor chip or the like) constituting the charging unit 15 and the device driving unit 16 described above are arranged at predetermined positions, and are connected to the liquid crystal display panel through wiring or the like. Thus, the liquid crystal display device 1 shown in FIG. 1 is completed.

[Operation and effect of liquid crystal display device 1]
(1. Basic operation)
In this liquid crystal display device 1, light source light (backlight light) emitted from the backlight 10 is controlled by pixels (red pixels 14 R, green) in the liquid crystal display panel (liquid crystal layer 13) according to control by a drive circuit (not shown). Each pixel 14G and blue pixel 14B) is modulated. Thereby, display light (backlight light modulated for each pixel) including red light, green light, and blue light is emitted from the observation surface side (front surface side) of the liquid crystal display panel. In this way, a color video display is performed on the liquid crystal display device 1.

(2. Action of characteristic parts)
Here, with reference to FIG. 4 to FIG. 6 in addition to FIG. 1, the operation of the characteristic part in the present embodiment will be described in detail in comparison with comparative examples (Comparative Examples 1 and 2).

(Comparative Example 1)
FIG. 4 schematically illustrates a cross-sectional configuration of the liquid crystal display device (liquid crystal display device 100) according to Comparative Example 1. The liquid crystal display device 100 of Comparative Example 1 includes a backlight 10 and a liquid crystal display panel including a TFT substrate 101, a liquid crystal layer 13, and a CF substrate 102 from the back side to the front side. That is, in the liquid crystal display device 1 according to the present embodiment, the TFT substrate 101 and the CF substrate 102 are provided instead of the TFT substrate 11 and the CF substrate 12, and the charging unit 15 and the device driving unit 16 are excluded. The structure of is the same.

  The TFT substrate 101 includes a plurality of photodiodes 123 in the inter-pixel region in addition to the element formation substrate 110 and the plurality of pixel electrodes 111 described above. That is, the TFT substrate 101 is obtained by further providing a plurality of photodiodes 123 in the TFT substrate 11.

  In addition to the counter substrate 120, the color filter layer 121, and the common electrode 122 described above, the CF substrate 102 includes a plurality of light-shielding portions (black matrix portions) 104 in the inter-pixel region in order to improve contrast during video display. doing. That is, the CF substrate 102 is configured such that a plurality of light shielding portions 104 are provided in the inter-pixel region instead of the plurality of photodiodes 123 in the CF substrate 12.

  Thus, unlike the liquid crystal display device 1, the liquid crystal display device 101 has a plurality of photodiodes 123 formed not in the CF substrate 102 but in the TFT substrate 101. For this reason, in the liquid crystal display device 101, the manufacturing process becomes complicated (the manufacturing process increases), and the manufacturing cost increases. Specifically, in a conventional liquid crystal display device incorporating a photodiode or a solar cell, it is common to form a photodiode on the TFT substrate side because of the advantage that a manufacturing apparatus can be used when manufacturing a TFT substrate. . However, since the number of manufacturing steps on the TFT substrate side is remarkably increased, problems such as a decrease in manufacturing yield, an increase in manufacturing cost and an increase in process load are caused.

(Comparative Example 2)
On the other hand, FIG. 5 schematically shows a cross-sectional configuration of a liquid crystal display device (liquid crystal display device 200) according to Comparative Example 2. The liquid crystal display device 200 of Comparative Example 2 includes a backlight 10 and a liquid crystal display panel including a TFT substrate 11, a liquid crystal layer 13, and a CF substrate 202 from the back side to the front side. That is, in the liquid crystal display device 1, the CF substrate 202 is provided instead of the CF substrate 12, and the other configurations except for the charging unit 15 and the device driving unit 16 are the same.

  The CF substrate 202 includes a plurality of photodiodes 203 in the inter-pixel region in addition to the counter substrate 120, the color filter layer 121, and the common electrode 122 described above. That is, the CF substrate 202 is configured such that a plurality of photodiodes 203 are provided in the inter-pixel region instead of the plurality of photodiodes 123 in the CF substrate 12.

  The photodiode 203 includes a transparent electrode 123T1 and an n-type semiconductor from the film surface side (back side, liquid crystal layer 13 side) in the CF substrate 202 toward the counter substrate 120 side (front side, opposite to the liquid crystal layer 13). The layer 123N, the i-type semiconductor layer 123I, the p-type semiconductor layer 123P, and the transparent electrode 123T2 are stacked in this order. That is, in the photodiode 123, one side of the photoelectric conversion layer (n-type semiconductor layer 123N, i-type semiconductor layer 123I, and p-type semiconductor layer 123P) is a transparent electrode 123T, and the other side is a light-shielding electrode 123S. On the other hand, in the photodiode 203, both sides of the photoelectric conversion layer are transparent electrodes (transparent electrodes 123T1 and 123T2). Here, the transparent electrode 123T2 on the counter substrate 120 side is an electrode common to each photodiode 203 here.

  In the liquid crystal display device 200 having such a configuration, the photoelectric conversion including the photodiode 203 (the n-type semiconductor layer 123N, the i-type semiconductor layer 123I, and the p-type semiconductor layer 123P is performed while allowing light to enter the photodiode 203. Layer) functions as a black matrix portion. As a result, the contrast at the time of video display is improved, and the black matrix portion is formed on the CF substrate 202 side. Therefore, the manufacturing process is simplified compared to the liquid crystal display device 100 of the first comparative example. , Manufacturing costs can be reduced. Specifically, by avoiding an increase in the number of manufacturing steps on the TFT substrate 11 side and allocating to the CF substrate 202 side where the number of manufacturing steps is relatively small, the risk of a decrease in manufacturing yield is reduced.

  However, in the liquid crystal display device 200, as described above, due to the function of the photoelectric conversion layer in the photodiode 203 as a black matrix portion (light-shielding portion), a coloring phenomenon occurs in the black matrix portion. End up. Specifically, for example, when the photoelectric conversion layer is made of amorphous silicon (a-Si), the amorphous silicon is a material closer to reddish brown rather than black, so the image also looks reddish. (Coloring phenomenon to the red side will occur). In this way, in the liquid crystal display device 200, it can be said that it is difficult to apply to a general-purpose display because the display quality is likely to deteriorate in the display color.

(Operation of this embodiment)
On the other hand, in the liquid crystal display device 1 according to the present embodiment, first, as shown in FIGS. 1 and 6, the light is incident on the photodiode 123 while the photodiode 123 (light-shielding electrode 123S). However, it functions as a black matrix part (light-shielding part). That is, for example, as shown in FIG. 6, here, the backlight lights Lb1, Lb2 and the like emitted from the backlight 10 enter the photodiode 123 from the transparent electrode 123T side. On the other hand, ambient light Le1, Le2, and the like incident from the outside are blocked by the light shielding electrode 123S and do not enter the photodiode 123 (in the photoelectric conversion layer). Further, the backlight lights Lb1, Lb2 and the like described above are also blocked by the light shielding electrode 123S and are not emitted to the outside.

  As a result, in the liquid crystal display device 1 as well as the liquid crystal display device 200 of the comparative example 2, the contrast at the time of image display is improved, and the black matrix portion is formed on the CF substrate 12 side. Therefore, the manufacturing process is simplified and the manufacturing cost can be reduced as compared with the liquid crystal display device 100 of the first comparative example.

  In the liquid crystal display device 1, as shown in FIGS. 1 and 6, in the photodiode 123, one side of the photoelectric conversion layer (n-type semiconductor layer 123N, i-type semiconductor layer 123I, and p-type semiconductor layer 123P) is transparent. The electrode 123T and the other side serve as a light shielding electrode 123S. In other words, the light shielding electrode 123S in the photodiode 123 functions as a black matrix portion.

  Thus, unlike the liquid crystal display device 200 of Comparative Example 2 in which both sides of the photoelectric conversion layer are made transparent electrodes (transparent electrodes 123T1, 123T2) and the photoelectric conversion layer itself functions as a black matrix portion, black Occurrence of a coloring phenomenon in the matrix portion is avoided. Specifically, the occurrence of the coloring phenomenon on the red side is avoided, and the display quality in the display color or the like is less likely to be reduced. As a result, application to a general-purpose display becomes easy.

  Further, the backlight lights Lb1, Lb2, and the like received from the transparent electrode 123S side of the photodiode 123 in this way are supplied to the charging unit 15 as electrical outputs. That is, the charging unit 15 performs a charging operation on the battery based on the backlight light emitted from the backlight 10 and incident on the photodiode 123 through the liquid crystal layer 13 and the like. And the apparatus drive part 16 drives the load in a predetermined apparatus (electronic equipment etc. which incorporate the liquid crystal display device 1) using the electric power in this battery. In this way, the electric power obtained based on the backlight light (internal light) is returned to the battery, and low power consumption and energy saving are achieved.

  As described above, in the present embodiment, in the photodiode 123 disposed in the inter-pixel region in the CF substrate 12, one side of the photoelectric conversion layer is the transparent electrode 123T and the other side is the light shielding electrode 123S. Thus, it is possible to prevent the occurrence of a coloring phenomenon in the black matrix portion while making the light shielding electrode 123S function as a black matrix portion to improve contrast at the time of image display. Therefore, it is possible to improve the display image quality when displaying an image.

<Modification>
Subsequently, modified examples (modified examples 1 to 4) of the above-described embodiment will be described. In addition, the same code | symbol is attached | subjected about the component same as the said embodiment, and the description is abbreviate | omitted suitably.

[Modification 1]
FIG. 7 schematically illustrates a cross-sectional configuration of a liquid crystal display device (liquid crystal display device 1 </ b> A) according to the first modification. A liquid crystal display device 1A according to this modification includes a backlight 10 and a liquid crystal display panel including a TFT substrate 11, a liquid crystal layer 13, and a CF substrate 12A from the back side to the front side. The liquid crystal display device 1 </ b> A includes a charging unit 15 and a device driving unit 16. That is, the liquid crystal display device 1A is obtained by providing the liquid crystal display device 1 with the CF substrate 12A instead of the CF substrate 12, and the other configurations are the same. The CF substrate 12A corresponds to a specific example of “second substrate” in the present disclosure.

(CF substrate 12A)
The CF substrate 12A includes a plurality of photodiodes 123 in the inter-pixel region in addition to the counter substrate 120, the color filter layer 121, and the common electrode 122 described above. That is, the CF substrate 12A has basically the same configuration as the CF substrate 12.

  However, in the CF substrate 12A, the transparent electrodes 123T are shared by the photodiodes 123 and also serve as the common electrode 122 in each liquid crystal element (the transparent electrode 123T and the common electrode 122 are shared in the same layer). ).

  Also in the liquid crystal display device 1A of the present modification, as in the above embodiment, in the photodiode 123, one side of the photoelectric conversion layer is a transparent electrode 123T and the other side is a light shielding electrode 123S. That is, the light shielding electrode 123S in the photodiode 123 functions as a black matrix portion. Therefore, as in the above embodiment, the backlight lights Lb1, Lb2, etc. emitted from the backlight 10 enter the photodiode 123 from the transparent electrode 123T side. On the other hand, ambient light Le1, Le2, and the like incident from the outside are blocked by the light shielding electrode 123S and do not enter the photodiode 123 (in the photoelectric conversion layer). Further, the backlight lights Lb1, Lb2 and the like described above are also blocked by the light shielding electrode 123S and are not emitted to the outside.

  Thereby, also in this modification, it is possible to acquire the same effect by the same operation as the above-mentioned embodiment. In other words, the shading electrode 123S functions as a black matrix portion to improve the contrast at the time of video display, and the occurrence of coloring phenomenon in the black matrix portion can be prevented, and the display image quality at the time of video display is improved. It becomes possible. In addition, the charging unit 15 can return the electric power obtained based on the backlight light (internal light) to the battery, so that low power consumption and energy saving can be achieved.

  In particular, in the present modification, since the transparent electrode 123T and the common electrode 122 are shared in the same layer, the manufacturing process can be further simplified and the manufacturing cost can be further reduced.

[Modification 2]
FIG. 8 schematically illustrates a cross-sectional configuration of a reflective liquid crystal display device (liquid crystal display device 1B) according to the second modification. A liquid crystal display device 1B according to this modification includes a liquid crystal display panel including a TFT substrate 11B, a liquid crystal layer 13, and a CF substrate 12 from the back side to the front side. The liquid crystal display device 1 </ b> B includes a charging unit 15 </ b> B and a device driving unit 16. That is, in the liquid crystal display device 1B, the backlight 10 is not provided (omitted) in the liquid crystal display device 1, and the TFT substrate 11B and the charging unit 15B are provided in place of the TFT substrate 11 and the charging unit 15, respectively. Other configurations are the same.

  In other words, the liquid crystal display devices 1 and 1A described so far and the liquid crystal display devices 1C and 1D described later perform image display using light source light (backlight light) emitted from the backlight 10, It is a transmissive liquid crystal display device. On the other hand, the liquid crystal display device 1B of the present modification is a reflective liquid crystal display device that displays an image using external light (environment light) instead of the light source light from the backlight 10.

  Here, the TFT substrate 11B corresponds to a specific example of “first substrate” in the present disclosure, and the charging unit 15B corresponds to a specific example of “second charging unit” in the present disclosure.

(TFT substrate 11B)
The TFT substrate 11B has pixel reflective electrodes 111B individually for each of a plurality of pixels (red pixels 14R, green pixels 14G, and blue pixels 14B) on the element formation substrate 110 (the liquid crystal layer 13 side). . That is, this TFT substrate 11B is obtained by providing a plurality of pixel reflection electrodes 111B instead of the plurality of pixel electrodes 111 on the TFT substrate 11, and the other configurations are basically the same.

  The pixel reflective electrode 111B is a reflective electrode configured using a reflective metal such as aluminum (Al) or silver (Ag). In such a pixel reflection electrode 111 </ b> B, the ambient light incident from the outside is reflected and then modulated, so that an image is displayed without using the backlight 10. Further, as shown in FIG. 8, ambient light Le1, Le2, and the like from the outside are reflected by the pixel reflective electrode 111B, and then are internally scattered light from the transparent electrode 123T side to the photodiode 123 (in the photoelectric conversion layer). Incident.

(Charging unit 15B)
Similarly to the charging unit 15, the charging unit 15 </ b> B performs a charging operation for a battery (secondary battery) (not shown) based on light incident on the photodiode 123 from the transparent electrode 123 </ b> T side. However, in this charging unit 15B, unlike the charging unit 15, as described above, ambient light (environment light Le1, Le2, etc.) incident on the photodiode 123 after being incident from the outside and reflected by the pixel reflective electrode 111B. Based on this, such a charging operation is performed.

  Also in the liquid crystal display device 1B of the present modification, as in the above embodiment, in the photodiode 123, one side of the photoelectric conversion layer is the transparent electrode 123T and the other side is the light shielding electrode 123S. That is, the light shielding electrode 123S in the photodiode 123 functions as a black matrix portion.

  Thereby, also in this modification, it is possible to acquire the same effect by the same operation as the above-mentioned embodiment. In other words, the shading electrode 123S functions as a black matrix portion to improve the contrast at the time of video display, and the occurrence of coloring phenomenon in the black matrix portion can be prevented, and the display image quality at the time of video display is improved. It becomes possible.

  Further, in the present modification, the charging unit 15B can supply the power obtained based on the ambient light (external light) to the battery, so that the power consumption and the energy saving can be reduced as in the above embodiment. It is also possible to plan. That is, in the reflective liquid crystal display device, in general, the power consumption in the backlight is unnecessary, so that the power consumption is reduced as compared with the transmissive liquid crystal display device. It is possible to reduce power consumption.

  In the present modification, the transparent electrode 123T is shared by the photodiodes 123 as in the first modification, and also serves as the common electrode 122 in each liquid crystal element (the transparent electrode 123T and the common electrode). 122 may be shared by the same layer).

[Modifications 3 and 4]
FIG. 9 schematically illustrates a cross-sectional configuration of a liquid crystal display device (liquid crystal display device 1C) according to the third modification. FIG. 10 illustrates a liquid crystal display device (liquid crystal display device 1D) according to the fourth modification. A cross-sectional configuration is schematically shown.

  Each of these liquid crystal display devices 1C and 1D includes a backlight 10, a liquid crystal display panel including a TFT substrate 11, a liquid crystal layer 13, and a CF substrate 12C from the back side to the front side. However, the liquid crystal display device 1C includes a charging unit 15C and a device driving unit 16 in addition to these, whereas the liquid crystal display device 1D includes a backlight control unit 17 and a backlight driving unit 18.

  That is, the liquid crystal display device 1C is the same as the liquid crystal display device 1 except that the CF substrate 12C and the charging unit 15C are provided instead of the CF substrate 12 and the charging unit 15, respectively. The liquid crystal display device 1D is the same as the liquid crystal display device 1 except that the CF substrate 12C, the backlight control unit 17, and the backlight driving unit 18 are provided instead of the CF substrate 12, the charging unit 15, and the device driving unit 16. Other configurations are the same.

  Here, the TFT substrate 12C corresponds to a specific example of “second substrate” in the present disclosure, and the charging unit 15C corresponds to a specific example of “third charging unit” in the present disclosure. Further, the backlight control unit 17 and the backlight driving unit 18 correspond to a specific example of a “light control unit” in the present disclosure.

(CF substrate 12C)
The CF substrate 12C includes a plurality of photodiodes 123C in the inter-pixel region in addition to the counter substrate 120, the color filter layer 121, and the common electrode 122 described above. That is, the CF substrate 12C is obtained by providing a plurality of photodiodes 123C in the inter-pixel region instead of the plurality of photodiodes 123 in the CF substrate 12.

  The photodiode 123C includes a light shielding electrode 123S and an n-type semiconductor from the film surface side (back side, liquid crystal layer 13 side) in the CF substrate 12C toward the counter substrate 120 side (front side, opposite to the liquid crystal layer 13). The layer 123N, the i-type semiconductor layer 123I, the p-type semiconductor layer 123P, and the transparent electrode 123T are stacked in this order. That is, in the photodiode 123 described so far, the back side as one side of the photoelectric conversion layer (n-type semiconductor layer 123N, i-type semiconductor layer 123I and p-type semiconductor layer 123P) is the transparent electrode 123T, and the front side as the other side is A light shielding electrode 123S is formed. On the other hand, in the photodiode 123C of the modification examples 3 and 4, contrary to the photodiode 123 described above, the front side as one side of the photoelectric conversion layer is the transparent electrode 123T, and the back side as the other side is the light shielding electrode 123S. ing. Here, the transparent electrode 123T on the counter substrate 120 side is an electrode common to the photodiodes 123C here.

  With the photodiode 123C having such a configuration, the ambient light Le1, Le2, and the like incident from the outside enter the photodiode 123 from the transparent electrode 123T side as shown in FIGS. 9 and 10 on the CF substrate 12C. To do. On the other hand, the backlight lights Lb1, Lb2, etc. emitted from the backlight 10 are blocked by the light shielding electrode 123S and do not enter the photodiode 123 (in the photoelectric conversion layer).

(Charging unit 15C)
Similarly to the charging unit 15, the charging unit 15 </ b> C illustrated in FIG. 9 performs a charging operation for a battery (secondary battery) (not illustrated) based on light incident on the photodiode 123 from the transparent electrode 123 </ b> T side. is there. However, in the charging unit 15C, unlike the charging unit 15, as described above, such charging operation is performed based on the environmental light (environment light Le1, Le2, etc.) incident from the outside and directly incident on the photodiode 123, as described above. Is supposed to do.

(Backlight control unit 17, backlight drive unit 18)
The backlight control unit 17 shown in FIG. 10 controls the backlight driving unit 18 based on the environmental light (environment light Le1, Le2, etc.) incident from the outside and directly incident on the photodiode 123 (dimming control, etc.). ). In addition, the backlight driving unit 18 performs driving (e.g., light emission driving) with respect to the backlight 10.

  In this way, in the backlight control unit 17 and the backlight driving unit 18, dimming control for the backlight 10 is performed based on the environmental light (environment light Le1, Le2, etc.) incident from the outside and directly incident on the photodiode 123. It is possible to do.

  As described above, in the liquid crystal display devices 1C and 1D of the third and fourth modifications, it is possible to obtain the same effect by the same operation as in the above embodiment. In other words, the shading electrode 123S functions as a black matrix portion to improve the contrast at the time of video display, and the occurrence of coloring phenomenon in the black matrix portion can be prevented, and the display image quality at the time of video display is improved. It becomes possible.

  Further, in the liquid crystal display device 1C according to the third modification, the charging unit 15C can supply the power obtained based on the ambient light (external light) to the battery. Therefore, the power consumption is low as in the above embodiment. And energy saving.

  On the other hand, in the liquid crystal display device 1D of the modified example 4, the dimming control for the backlight 10 can be performed based on the ambient light incident from the outside and directly incident on the photodiode 123. Therefore, the use of the liquid crystal display device 1D is possible. Dimming control according to the environment (illuminance of ambient light) becomes possible. Therefore, also in the fourth modification, it is possible to achieve low power consumption and energy saving similarly to the above embodiment.

<Application example>
Next, with reference to FIGS. 11 to 15, application examples of the liquid crystal display devices (liquid crystal display devices 1 and 1 </ b> A to 1 </ b> D) according to the above embodiment and the modified examples (modified examples 1 to 4) will be described. The liquid crystal display device according to the above embodiment and the like can be applied to electronic devices in various fields such as a television device, a digital camera, a notebook personal computer, a mobile terminal device such as a mobile phone, or a video camera. In other words, the liquid crystal display device can be applied to electronic devices in various fields that display a video signal input from the outside or a video signal generated inside as an image or video.

(Application example 1)
FIG. 11 illustrates an appearance of a television device to which the liquid crystal display device of the above-described embodiment or the like is applied. This television apparatus has, for example, a video display screen unit 510 including a front panel 511 and a filter glass 512, and the video display screen unit 510 is configured by the liquid crystal display device of the above-described embodiment or the like.

(Application example 2)
FIG. 12 illustrates an appearance of a digital camera to which the liquid crystal display device according to the above-described embodiment or the like is applied. This digital camera has, for example, a light emitting unit 521 for flash, a display unit 522, a menu switch 523, and a shutter button 524, and the display unit 522 is configured by the liquid crystal display device of the above-described embodiment or the like. .

(Application example 3)
FIG. 13 illustrates an appearance of a notebook personal computer to which the liquid crystal display device of the above-described embodiment or the like is applied. This notebook personal computer has, for example, a main body 531, a keyboard 532 for inputting characters and the like, and a display unit 533 for displaying an image. The display unit 533 is a liquid crystal display device according to the above-described embodiment or the like. It is comprised by.

(Application example 4)
FIG. 14 shows the appearance of a video camera to which the liquid crystal display device of the above-described embodiment and the like is applied. This video camera includes, for example, a main body 541, a subject shooting lens 542 provided on the front side surface of the main body 541, a start / stop switch 543 at the time of shooting, and a display 544. The display unit 544 includes the liquid crystal display device of the above-described embodiment or the like.

(Application example 5)
FIG. 15 illustrates an appearance of a mobile phone to which the liquid crystal display device of the above-described embodiment or the like is applied. For example, the mobile phone is obtained by connecting an upper housing 710 and a lower housing 720 with a connecting portion (hinge portion) 730, and includes a display 740, a sub-display 750, a picture light 760, and a camera 770. Yes. The display 740 or the sub-display 750 is configured by the liquid crystal display device of the above-described embodiment or the like.

<Other variations>
As described above, the technology of the present disclosure has been described with the embodiment, the modification, and the application example. However, the present technology is not limited to the embodiment and the like, and various modifications can be made.

  For example, in the above embodiment and the like, a case where a semiconductor layer (photoelectric conversion layer) in a photodiode (photoelectric conversion element) is mainly composed of an amorphous semiconductor (amorphous silicon or the like) is taken as an example. Although explained, it is not limited to this. That is, the above-described semiconductor layer may be configured of, for example, a polycrystalline semiconductor (polycrystalline silicon or the like) or a microcrystalline semiconductor (microcrystalline silicon or the like).

  In the above-described embodiments and the like, the case where the photoelectric conversion element is configured by a PIN type photodiode has been described as an example. However, the present invention is not limited to this, and a photo of a type other than the PIN type (for example, PN type) is used. You may comprise a photoelectric conversion element with a diode.

In addition, this technique can also take the following structures.
(1)
A first substrate;
A second substrate having a color filter layer disposed for each of a plurality of pixels and a plurality of photoelectric conversion elements disposed in an inter-pixel region;
A liquid crystal layer provided between the first substrate and the second substrate,
The photoelectric conversion element includes a photoelectric conversion layer, a transparent electrode provided on one side of the photoelectric conversion layer, and a light-shielding electrode provided on the other side of the photoelectric conversion layer.
(2)
The liquid crystal display device according to (1), wherein the first substrate is disposed on a back side and the second substrate is disposed on a front side.
(3)
In the second substrate,
The transparent electrode is disposed on the back side as the one side,
The liquid crystal display device according to (2), wherein the light shielding electrode is disposed on a front surface side as the other side.
(4)
The liquid crystal display device according to (3), wherein a light source unit is provided on a back side of the first substrate.
(5)
The liquid crystal display device according to (4), further including a first charging unit that performs a charging operation based on light source light emitted from the light source unit and incident on the photoelectric conversion element via the liquid crystal layer.
(6)
The first substrate has a pixel reflection electrode for each of the plurality of pixels;
The liquid crystal display device according to (3), which is configured as a reflective liquid crystal display device.
(7)
The liquid crystal display device according to (6), further including a second charging unit that performs a charging operation based on ambient light that is incident from the outside and is reflected by the pixel reflective electrode and then is incident on the photoelectric conversion element.
(8)
In the second substrate,
The transparent electrode is disposed on the front side as the one side,
The liquid crystal display device according to (2), wherein the light shielding electrode is disposed on a back side as the other side.
(9)
The liquid crystal display device according to (8), further including a third charging unit that performs a charging operation based on ambient light incident on the photoelectric conversion element from the outside.
(10)
A light source unit disposed on the back side of the first substrate;
The liquid crystal display device according to (8), further comprising: a dimming unit that performs dimming control on the light source unit based on ambient light incident on the photoelectric conversion element from outside.
(11)
A liquid crystal element is formed for each of the plurality of pixels,
The liquid crystal display device according to any one of (1) to (10), wherein the plurality of photoelectric conversion elements share the transparent electrode, and the transparent electrode also serves as a common electrode in the liquid crystal element. .
(12)
The liquid crystal display device according to any one of (1) to (11), wherein the light shielding electrode functions as a black matrix portion.
(13)
The liquid crystal display device according to any one of (1) to (12), wherein the photoelectric conversion element includes a PIN photodiode.
(14)
With a liquid crystal display,
The liquid crystal display device
A first substrate;
A second substrate having a color filter layer disposed for each of a plurality of pixels and a plurality of photoelectric conversion elements disposed in an inter-pixel region;
A liquid crystal layer provided between the first substrate and the second substrate,
The photoelectric conversion device includes a photoelectric conversion layer, a transparent electrode provided on one side of the photoelectric conversion layer, and a light shielding electrode provided on the other side of the photoelectric conversion layer.
(15)
Forming a first substrate;
Forming a second substrate having a color filter layer disposed for each of a plurality of pixels and a plurality of photoelectric conversion elements disposed in an inter-pixel region;
Forming a liquid crystal layer between the first substrate and the second substrate,
In the step of forming the second substrate, the photoelectric conversion element includes a photoelectric conversion layer, a transparent electrode provided on one side of the photoelectric conversion layer, and a light shielding electrode provided on the other side of the photoelectric conversion layer. A method of manufacturing a liquid crystal display device.

  DESCRIPTION OF SYMBOLS 1,1A-1D ... Liquid crystal display device, 10 ... Back light, 11, 11B ... TFT substrate, 110 ... Element formation substrate, 111 ... Pixel electrode, 111B ... Pixel reflective electrode, 12, 12A, 12C ... CF substrate, 120 ... Counter substrate, 121 ... color filter layer, 121R ... red color filter, 121G ... green color filter, 121B ... blue color filter, 122 ... common electrode, 123, 123C ... photodiode, 123P ... p-type semiconductor layer, 123I ... i-type Semiconductor layer, 123N ... n-type semiconductor layer, 123S ... light shielding electrode, 123T ... transparent electrode, 13 ... liquid crystal layer, 14R ... red pixel, 14G ... green pixel, 14B ... blue pixel, 15, 15B, 15C ... charge unit, 16 ... device drive unit, 17 ... backlight control unit, 18 ... backlight drive unit, Lb1, Lb2 ... backlight Light, Le1, Le2 ... ambient light.

Claims (15)

A first substrate;
A second substrate having a color filter layer disposed for each of a plurality of pixels and a plurality of photoelectric conversion elements disposed in an inter-pixel region;
A liquid crystal layer provided between the first substrate and the second substrate,
The photoelectric conversion element includes a photoelectric conversion layer, a transparent electrode provided on one side of the photoelectric conversion layer, and a light-shielding electrode provided on the other side of the photoelectric conversion layer. The liquid crystal display device according to claim 1, wherein the first substrate is disposed on a back surface side, and the second substrate is disposed on a front surface side. In the second substrate,
The transparent electrode is disposed on the back side as the one side,
The liquid crystal display device according to claim 2, wherein the light shielding electrode is disposed on a front surface side as the other side. The liquid crystal display device according to claim 3, further comprising a light source unit on a back side of the first substrate. The liquid crystal display device according to claim 4, further comprising a first charging unit that performs a charging operation based on light source light that is emitted from the light source unit and is incident on the photoelectric conversion element through the liquid crystal layer. The first substrate has a pixel reflection electrode for each of the plurality of pixels;
The liquid crystal display device according to claim 3, wherein the liquid crystal display device is configured as a reflective liquid crystal display device. The liquid crystal display device according to claim 6, further comprising a second charging unit that performs a charging operation based on ambient light that is incident from the outside and is reflected by the pixel reflective electrode and then is incident on the photoelectric conversion element. In the second substrate,
The transparent electrode is disposed on the front side as the one side,
The liquid crystal display device according to claim 2, wherein the light shielding electrode is disposed on a back side as the other side. The liquid crystal display device according to claim 8, further comprising a third charging unit that performs a charging operation based on ambient light incident on the photoelectric conversion element from outside. A light source unit disposed on the back side of the first substrate;
The liquid crystal display device according to claim 8, further comprising: a dimming unit that performs dimming control on the light source unit based on ambient light incident on the photoelectric conversion element from outside. A liquid crystal element is formed for each of the plurality of pixels,
The liquid crystal display device according to claim 1, wherein the transparent electrode is shared by the plurality of photoelectric conversion elements, and the transparent electrode also serves as a common electrode in the liquid crystal element. The liquid crystal display device according to claim 1, wherein the light shielding electrode functions as a black matrix portion. The liquid crystal display device according to claim 1, wherein the photoelectric conversion element is a PIN type photodiode. With a liquid crystal display,
The liquid crystal display device
A first substrate;
A second substrate having a color filter layer disposed for each of a plurality of pixels and a plurality of photoelectric conversion elements disposed in an inter-pixel region;
A liquid crystal layer provided between the first substrate and the second substrate,
The photoelectric conversion device includes a photoelectric conversion layer, a transparent electrode provided on one side of the photoelectric conversion layer, and a light shielding electrode provided on the other side of the photoelectric conversion layer. Forming a first substrate;
Forming a second substrate having a color filter layer disposed for each of a plurality of pixels and a plurality of photoelectric conversion elements disposed in an inter-pixel region;
Forming a liquid crystal layer between the first substrate and the second substrate,
In the step of forming the second substrate, the photoelectric conversion element includes a photoelectric conversion layer, a transparent electrode provided on one side of the photoelectric conversion layer, and a light shielding electrode provided on the other side of the photoelectric conversion layer. A method of manufacturing a liquid crystal display device.

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