JP2021189335A - Photoelectric elements and display panel using the same - Google Patents

Abstract

To enhance value of using a color filter structure of a display panel.SOLUTION: A color filter structure 14 of a display panel 10 includes a plurality of photoelectric elements 16, instead of at least a part of color resists, having a PIN structure in which P-type doped layers 18 and N-type doped layers 20 are separated by undoped layers 22. The plurality of photoelectric elements 16 include first to third photoelectric elements 16A to 16C on which undoped layers 22 are respectively formed by three types of semiconductors with band gaps different from one another, and which realize an RGB light transmission pattern. As a result, color filter functions can be performed by adjusting the band gaps of the semiconductors forming the undoped layers 22 of the plurality of photoelectric elements 16. In addition, value of using the color filter structure 14 can be enhanced because a various functions using the plurality of photoelectric elements 16 can be performed.SELECTED DRAWING: Figure 1

Description

The present invention relates to a photoelectric element and a display panel using the photoelectric element.

The conventional liquid crystal display panel has, for example, a structure as disclosed in Patent Document 1 and a structure as shown in FIG. With reference to FIG. 5, the conventional display panel 100 includes a glass substrate 30, a color filter structure 102, a liquid crystal 40, an array substrate 52, a glass substrate 54, and a backlight module 60. The light emitted from the backlight module 60 passes through the liquid crystal 40 whose liquid crystal molecular arrangement is electrically controlled, and is given a hue in the color filter structure 102 and emitted. That is, the light that passes through the red color resist (R) is emitted as red light RL, and the light that passes through the green color resist (G) is emitted as green light GL and passes through the blue color resist (B). The light is emitted as blue light BL.

Utility Model Registration No. 3109890

Here, the color filter structure 102 of the conventional display panel 100 as described above creates various colors by using the three primary colors of RGB, and a mixture of two adjacent colors by shading of a black matrix (BM). However, there was no other effective use, and there was room for improvement.
The present invention has been made in view of the above problems, and an object of the present invention is to enhance the utility value of a color filter structure of a display panel.

(Aspect of the invention)
The following aspects of the invention exemplify the configurations of the present invention and are described separately in order to facilitate understanding of the various configurations of the present invention. Each section does not limit the technical scope of the present invention, and some of the components of each section are replaced, deleted, or further while taking into consideration the best mode for carrying out the invention. Those to which the constituent elements of the above are added can also be included in the technical scope of the present invention.

(1) At least one type of photoelectric device having a PIN structure in which a P-type dope layer and an N-type dope layer are separated by an undoped layer, to which a band gap is adjusted and light transmission characteristics having a predetermined range of wavelengths are imparted. A photoelectric element used as an RGB light transmission pattern and / or a black matrix in a color filter structure of a display panel by forming the undoped layer with the semiconductor of the above.

The photoelectric element described in this section has a PIN structure in which a P-type dope layer and an N-type dope layer are separated by an undoped layer, and the undoped layer is formed of at least one type of semiconductor. The bandgap of at least one type of semiconductor forming the undoped layer is adjusted so as to impart light transmission characteristics having a wavelength in a predetermined range. For this reason, three types of semiconductors, a semiconductor adjusted to transmit red light, a semiconductor adjusted to transmit green light, and a semiconductor adjusted to transmit blue light, are used. The three types of photoelectric elements on which the undoped layer is formed realize a light transmission pattern of RGB, which is the three primary colors.

Further, a black matrix is realized by a photoelectric element in which an undoped layer is formed so as to block light of any wavelength of RGB by, for example, a combination of a plurality of semiconductors having an adjusted band gap. Therefore, these photoelectric elements are used as an RGB light transmission pattern and a black matrix in place of the color resist in the color filter structure of the display panel. As a result, in such a color filter structure, not only the color arrangement but also various functions using the photoelectric element are realized, so that the utility value of the color filter structure is improved.

(2) A display panel in which light emitted from a light source is arranged by a color filter structure and emitted from a display screen. The color filter structure is a P-type dope layer instead of at least a part of the color resist. A plurality of photoelectric elements having a PIN structure in which the N-type dope layer is separated by an undoped layer are provided, and the plurality of photoelectric elements include a first photoelectric element that realizes a red light transmission pattern and a green light transmission. A second photoelectric element that realizes a pattern and a third photoelectric element that realizes a blue light transmission pattern include at least one type of photoelectric element, and the first to third photoelectric elements have a band gap. A display panel in which each of the undoped layers is formed by three types of semiconductors different from each other.

The display panel described in this section arranges the light emitted from the light source through a color filter structure and emits the light from the display screen, and the color filter structure has a plurality of colors instead of at least a part of the color resist. The photoelectric element of the above is provided. These plurality of photoelectric elements have a PIN structure in which a P-type dope layer and an N-type dope layer are separated by an undoped layer, and include at least one of the first to third photoelectric elements. I'm out. In these first to third photoelectric elements, an undoped layer is formed by three types of semiconductors having different band gaps so as to realize each light transmission pattern of RGB.

That is, for example, in the first photoelectric element, an undoped layer is formed by a semiconductor adjusted to transmit red light, and in the second photoelectric element, an undoped layer is formed by a semiconductor adjusted to transmit green light. The undoped layer is formed in the third photoelectric element by the semiconductor adjusted to transmit blue light. As a result, in the display panel described in this section, the function of the color filter is realized by adjusting the band gap of the semiconductor forming the undoped layer of the plurality of photoelectric elements. Further, in addition to the color arrangement function for the light emitted from the light source, various functions using a plurality of photoelectric elements are realized by the color filter structure, so that the utility value of the color filter structure is improved. It becomes a thing.

(3) In the above item (2), the display panel in which the light source is a backlight module.
In the display panel described in this section, since the light source is a backlight module, an appropriate amount of light can be easily obtained as a display device.

(4) In the above items (2) and (3), the plurality of photoelectric elements include a fourth photoelectric element in which the three types of semiconductors are stacked to form the undoped layer, and the fourth photoelectric element is formed. A display panel that realizes a black matrix.
In the display panel described in this section, the plurality of photoelectric elements used in the color filter structure include a fourth photoelectric element in addition to the first to third photoelectric elements. In this fourth photoelectric element, three types of semiconductors forming the undoped layer of the first to third photoelectric elements are laminated to form an undoped layer.

That is, a semiconductor whose bandgap is adjusted to transmit red light, a semiconductor whose bandgap is adjusted to transmit green light, and a semiconductor whose bandgap is adjusted to transmit blue light are It is piled up. In other words, a semiconductor that absorbs light having a wavelength other than red light, a semiconductor that absorbs light having a wavelength other than green light, and a semiconductor that absorbs light having a wavelength other than blue light are superimposed. As a result, a black matrix that blocks light of any wavelength of RGB is realized by the fourth photoelectric element, so that a black matrix may be realized by using a semiconductor different from the first to third photoelectric elements. In comparison, the cost will be suppressed.

(5) In the above items (2) to (4), the color filter structure includes a pair of transparent electrode layers arranged so as to sandwich the plurality of photoelectric elements, and is configured to be operable as a power generation mode. In the power generation mode, each of the light-transmitting photoelectric elements included in the plurality of photoelectric elements among the first to third photoelectric elements reaches the light source and / or through each of the electrode layers. Alternatively, a display panel that absorbs incident light from the surroundings according to the light absorption characteristics of the semiconductor forming the undoped layer, and the pair of electrode layers draws current from the light-transmitting photoelectric element.

In the display panel described in this section, the color filter structure includes a pair of transparent electrode layers, and a plurality of photoelectric elements are arranged between the pair of electrode layers, whereby a plurality of photoelectric elements are replaced with the color resist. The portion provided with the above has a structure in which one electrode layer, a P-type / N-type dope layer, an undoped layer, an N-type / P-type dope layer, and the other electrode layer are laminated in this order of description. Further, the color filter structure is configured to be operable as a power generation mode, and in this power generation mode, each of the light transmission photoelectric elements included in the plurality of photoelectric elements among the first to third photoelectric elements is Absorbs incident light from the light source and / or the surroundings. That is, each of the photoelectric elements for light transmission has incident light from a light source that has passed through one of the transparent electrode layers and incident light from the surroundings that has passed through the transparent electrode layer on the display screen side, depending on the position of the light source. Light, in other words, at least one of the incident light from the ambient environment in which the display panel incident via the display screen is arranged is absorbed by the semiconductor forming the undoped layer. Here, the photoelectric element for light transmission refers to the first to third photoelectric elements included in the plurality of photoelectric elements, and for example, the plurality of photoelectric elements include only the first photoelectric element. In the case of, the first photoelectric element is shown. When the plurality of photoelectric elements include the first photoelectric element and the third photoelectric element, the first and third photoelectric elements thereof are shown, and the first to third photoelectric elements are included in the plurality of photoelectric elements. When all the photoelectric elements of the above are included, all the first to third photoelectric elements are shown.

More specifically, for example, in the first photoelectric element, an undoped layer is formed by a semiconductor whose bandgap is adjusted so as to transmit red light, and the semiconductor causes other than red light such as green light and blue light. Absorbs light of wavelength. Therefore, the light-transmitting photoelectric element absorbs light having a wavelength corresponding to the light absorption characteristics of the semiconductor forming each undoped layer, and an electron-hole pair is generated in each undoped layer to generate an internal electric field. Cause. Then, in the power generation mode, the pair of electrode layers take out a current from the photovoltaic power generated by the separation of electron-hole pairs via the P-type dope layer and the N-type dope layer in the photoelectric element for light transmission. It is formed. As a result, the color filter structure of the display panel described in this section uses the light from the light source and / or the light from the surrounding environment to function like a solar cell to generate electricity, and its utility value is further increased. It will be improved.

(6) In the above items (2) to (4), the color filter structure comprises a pair of transparent electrode layers arranged so as to sandwich the plurality of photoelectric elements, and one of the pair of electrode layers. A plurality of TFT elements connected to the light-transmitting photoelectric element included in the plurality of photoelectric elements among the first to third photoelectric elements are included, and are configured to be operable as a sensing mode. In the sensing mode, the color filter structure is arranged so that the light emitted from the light source is emitted as red light from the display screen, and the plurality of TFT elements are photoelectric elements for light transmission. Each of the light-transmitting photoelectric elements provides a reverse bias to the semiconductor, and the reflected light emitted from the display screen and reflected by an object in contact with or close to the display screen is used to form the undoped layer. A display panel that absorbs light according to its light absorption characteristics, and the pair of electrode layers draws out a current from the light-transmitting photoelectric element and generates an electric signal according to the strength of the current for each taken-out current.

In the display panel described in this section, the color filter structure includes a pair of transparent electrode layers and a plurality of TFT elements. The pair of transparent electrode layers are arranged so as to sandwich the plurality of photoelectric elements, and the portion provided with the plurality of photoelectric elements instead of the color resist is one electrode layer, a P-type / N-type doped layer. , The undoped layer, the N-type / P-type doped layer, and the other electrode layer have a structure in which they are laminated in this order of description. The plurality of TFT elements are connected to the light-transmitting photoelectric elements included in the plurality of photoelectric elements among the first to third photoelectric elements via any one of the pair of electrode layers. That is, a layer on which a plurality of TFT elements are arranged is formed on the upper side or the lower side of the above-mentioned laminated structure. The light-transmitting photoelectric element here is the same as the light-transmitting photoelectric element described in the above section (5).

Further, the color filter structure is configured to be operable as a sensing mode, and controls a plurality of photoelectric elements and the like so that the light emitted from the light source is emitted as red light from the display screen in this sensing mode. And color scheme. Further, in the sensing mode, the plurality of TFT elements provide a reverse bias to the light transmitting photoelectric element to be connected, and each of these light transmitting photoelectric elements is emitted as red light from the display screen and displayed. Absorbs the reflected light reflected by an object that touches or is close to the screen. That is, the light-transmitting photoelectric element absorbs light having a wavelength corresponding to the light absorption characteristics of the semiconductor forming each undoped layer, thereby generating electron-hole pairs in each undoped layer and incorporating an electric field. Causes. Similarly, in the sensing mode, the pair of electrode layers take out a current from the photoelectric element for light transmission, and generate an electric signal according to the strength of the current for each of the taken out currents.

Here, the reflected light reflected by an object that is in contact with or close to the display screen is reflected at various levels of light and dark due to the reflection characteristics and the scattering characteristics according to the unevenness of the surface of the object. Therefore, the strength of the current taken out from each of the light-transmitting photoelectric elements changes depending on the level of lightness and darkness of the absorbed reflected light. Therefore, the pair of electrode layers generate an electric signal having a magnitude corresponding to the strength of the current for each current taken out from the photoelectric element for light transmission. Then, by adding the position information of the photoelectric element of the extraction source to each of these electric signals, planar signal information corresponding to the arrangement of the photoelectric element for light transmission can be obtained. As a result, the unevenness information of the object in contact with or close to the display screen can be obtained in a plane, so that it functions like an optical sensor for detecting fingerprints and the like, and the utility value of the color filter structure is further improved. ..

(7) In the above items (2) to (6), the first photoelectric element is amorphous whose band gap is adjusted to 1.7 to 1.95 eV so as to transmit light having a wavelength of 635 to 730 nm. A display panel in which the undoped layer is formed by silicon.
The display panel described in this section defines a semiconductor that forms an undoped layer of a first photoelectric element that transmits red light. That is, the undoped layer of the first photoelectric element is formed of amorphous silicon having a bandgap adjusted to 1.7 to 1.95 eV, and transmits light having a wavelength of 635 to 730 nm. As a result, the first photoelectric element that transmits red light can be easily realized.

(8) In the above items (2) to (7), the second photoelectric element has a bandgap adjusted to 1.8 to 2.26 eV so as to transmit light having a wavelength of 550 to 688 nm. A display panel on which the undoped layer is formed by gallium phosphide.
The display panel described in this section defines a semiconductor that forms an undoped layer of a second photoelectric element that transmits green light. That is, the undoped layer of the second photoelectric element is formed of gallium phosphide having a bandgap adjusted to 1.8 to 2.26 eV, and transmits light having a wavelength of 550 to 688 nm. As a result, a second photoelectric element that transmits green light can be easily realized.

(9) In the above items (2) to (8), the third photoelectric element has a bandgap adjusted to 2.1 to 3.2 eV so as to transmit light having a wavelength of 388 to 590 nm. A display panel on which the undoped layer is formed by indium gallium.
The display panel described in this section defines a semiconductor that forms an undoped layer of a third photoelectric element that transmits blue light. That is, the undoped layer of the third photoelectric element is formed of indium gallium nitride having a bandgap adjusted to 2.1 to 3.2 eV, and transmits light having a wavelength of 388 to 590 nm. As a result, a third photoelectric element that transmits blue light can be easily realized.

Since the present invention has the above-mentioned configuration, it is possible to increase the utility value of the color filter structure of the display panel.

It is sectional drawing which shows typically an example of the structure of the display panel which concerns on embodiment of this invention. It is an image cross-sectional view which shows an example of the structure of the black matrix of the color filter structure of FIG. FIG. 3 is an image structure diagram for each photoelectric element when the display panel of FIG. 1 is used in a power generation mode or a sensing mode. It is an image structure diagram in the configuration including the 1st to 4th photoelectric elements when the display panel of FIG. 1 is used in the power generation mode and the sensing mode. It is sectional drawing which shows typically the structure of the conventional display panel.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the accompanying drawings. Here, detailed description of the same parts or the corresponding parts as in the prior art will be omitted, and the same parts or the corresponding parts are indicated by the same reference numerals throughout the drawings.
FIG. 1 schematically shows the structure of the display panel 10 according to the embodiment of the present invention. As shown, the display panel 10 includes a glass substrate 30, a color filter structure 14, a liquid crystal 40, an array substrate 52, a glass substrate 54, and a backlight module 60 as a light source 60. Then, the light emitted from the backlight module 60, whose liquid crystal molecular arrangement passes through the electrically controlled liquid crystal 40, is colored by the color filter structure 14 and emitted from the display screen 12.

In the color filter structure 14, instead of the color resist constituting the conventional color filter structure 102 as shown in FIG. 5, a plurality of photoelectric elements 16 have a vertical and horizontal planar shape (the left-right direction in FIG. 1 and the direction orthogonal to the paper surface). It is provided side by side in the plane defined by. Each of these plurality of photoelectric elements 16 has a PIN structure in which the P-type dope layer 18 and the N-type dope layer 20 are separated by the undoped layer 22. The P-type dope layer 18 and the N-type dope layer 20 may be located on either the upper side or the lower side of the undope layer 22 in FIG. 1 as long as they are in a positional relationship facing each other with the undope layer 22 interposed therebetween. Further, the plurality of photoelectric elements 16 are sandwiched by a pair of transparent electrode layers 26 and 28, and are connected to these electrode layers 26 and 28.

The plurality of photoelectric elements 16 include the first to fourth photoelectric elements 16A to 16D, and these first to fourth photoelectric elements 16A to 16D are formed of semiconductors having different undoped layers 22 from each other. In the present embodiment, the first photoelectric element 16A has an undoped layer 22 formed by a semiconductor whose bandgap is adjusted so as to transmit red light RL (in other words, absorb light having a wavelength other than red light RL). It is formed, and in each drawing, the undoped layer 22A of the first photoelectric element 16A is illustrated as “R”. Therefore, among the light emitted from the backlight module 60, the light passing through the first photoelectric element 16A is emitted from the display screen 12 as red light RL. For the undoped layer 22A of the first photoelectric element 16A, for example, amorphous silicon (a—Si: H) is used, the band gap thereof is adjusted to 1.7 to 1.95 eV, and the wavelength is 635 to 730 nm. Allows light to pass through.

On the other hand, in the second photoelectric element 16B, the undoped layer 22 is formed by a semiconductor whose bandgap is adjusted so as to transmit green light GL (in other words, absorb light having a wavelength other than green light GL). In each drawing, the undoped layer 22B of the second photoelectric element 16B is shown as “G”. Therefore, of the light emitted from the backlight module 60, the light passing through the second photoelectric element 16B is emitted from the display screen 12 as green light GL. For example, gallium phosphide (GaP) is used for the undoped layer 22B of the second photoelectric element 16B, the band gap thereof is adjusted to 1.8 to 2.26 eV, and light having a wavelength of 550 to 688 nm is transmitted. Let me.

Further, in the third photoelectric element 16C, the undoped layer 22 is formed by a semiconductor whose bandgap is adjusted so as to transmit blue light BL (in other words, absorb light having a wavelength other than blue light BL). In each drawing, the undoped layer 22C of the third photoelectric element 16C is shown as “B”. Therefore, among the light emitted from the backlight module 60, the light passing through the third photoelectric element 16C is emitted from the display screen 12 as blue light BL. For example, indium gallium nitride (InGaN) is used for the undoped layer 22C of the third photoelectric element 16C, the band gap thereof is adjusted to 2.1 to 3.2 eV, and light having a wavelength of 388 to 590 nm is transmitted. Let me.

On the other hand, in the fourth photoelectric element 16D, as shown in FIG. 2, three types of semiconductors used in the undoped layers 22A to 22C of the first to third photoelectric elements 16A to 16C are superposed, and the undoped layer 22 is formed. It is formed, and in each drawing, the undoped layer 22D of the fourth photoelectric element 16D is illustrated as "BM" indicating a black matrix. Therefore, among the light emitted from the backlight module 60, the light reaching the fourth photoelectric element 16D absorbs all wavelengths corresponding to the light absorption characteristics of each of the three types of semiconductors, and the display screen. It is absorbed without being emitted from 12. The fourth photoelectric element 16D is arranged between the first to third photoelectric elements 16A to 16C so that the first to third photoelectric elements 16A to 16C are not directly arranged next to each other. To. In FIG. 2, three types of semiconductors are stacked in the order of RGB (22A, 22B, 22C) from the top, but the order of superposition is arbitrary.

Although the first to third photoelectric elements 16A to 16C are shown one by one in FIG. 1, the left-right direction and the direction orthogonal to the paper surface in FIG. 1 with these three photoelectric elements 16A to 16C as constituent units are shown. The photoelectric elements 16A to 16C are arranged in a grid pattern in a plan view. The pair of transparent electrode layers 26, 28 sandwiching them are formed as a transparent conductive film (TCO) such as ITO, and are formed so as to draw a current from a plurality of photoelectric elements 16. Further, a glass substrate 30 is provided on the color filter structure 14, and in the example of FIG. 1, the upper surface of the glass substrate 30 is shown as a display screen 12. However, a polarizing plate or the like may be provided on the upper side of the glass substrate 30, and in this case, one surface of the polarizing plate or the like becomes the display screen 12.

Here, the color filter structure 14 of the display panel 10 according to the embodiment of the present invention is configured to be operable as a power generation mode or a sensing mode. When configured to be operable as a power generation mode, the color filter structure 14 operates, for example, as shown in FIGS. 3 and 4. First, taking the first photoelectric element 16A as an example, one photoelectric element 16 unit will be described. As shown in the left figure of FIG. 3, for light transmission included in the plurality of photoelectric elements 16 of the color filter structure 14. The incident light IA incident from the upper side of FIG. 3 and the incident light IB incident from the lower side of FIG. 3 are incident on each of the photoelectric elements 16. The incident light IA incident from the upper side of FIG. 3 is light from the surrounding environment in which the display panel 10 is installed, which corresponds to the illumination light and sunlight, and passes through the glass substrate 30 with reference to FIG. 1. It is incident on the photoelectric element 16. On the other hand, the incident light IB incident from the lower side of FIG. 3 is the light from the backlight module 60, and is incident on the photoelectric element 16 through the glass substrate 54, the array substrate 52, and the liquid crystal 40.

Then, in the power generation mode, each of the plurality of photoelectric elements 16 absorbs the incident light IA from the ambient environment according to the light absorption characteristics of the semiconductor forming the undoped layer 22. That is, in the example of FIG. 3, the first photoelectric element 16A has a wavelength band shorter than the wavelength of the semiconductor itself in the incident light IA, depending on the light absorption characteristics of the semiconductor forming the undoped layer 22A. Absorbs light. Then, electron-hole pairs are generated in the undoped layer 22A, and an internal electric current is generated. Therefore, the electron-hole pairs are separated by the N-type doped layer 20 / P-type doping layer 18, and the photovoltaic power generated by the electron-hole pairs is transparent. A current is drawn by the electrode layer 28. Such an image is illustrated in the upper right figure of FIG.

Further, each of the plurality of photoelectric elements 16 absorbs the incident light IB from the backlight module 60 in the power generation mode according to the light absorption characteristics of the semiconductor forming the undoped layer 22. That is, in the example of FIG. 3, the first photoelectric element 16A has a wavelength band shorter than the wavelength of the semiconductor itself in the incident light IB, depending on the light absorption characteristics of the semiconductor forming the undoped layer 22A. Absorbs light. Then, electron-hole pairs are generated in the undoped layer 22A, and an internal electric current is generated. Therefore, the electron-hole pairs are separated by the P-type doped layer 18 / N-type doping layer 20, and the photovoltaic power generated by the electron-hole pairs is transparent. A current is drawn by the electrode layer 26. The lower right figure of FIG. 3 illustrates such an image.

Although only the first photoelectric element 16A is shown in FIG. 3, as shown in FIG. 4, the undoped layers 22B and 22C are also formed by the second and third photoelectric elements 16B and 16C. Light is absorbed according to the light absorption characteristics of the formed semiconductor. Then, the incident light IA from the ambient environment or the incident light IB from the backlight module 60 generates photovoltaic power in each of the photoelectric elements 16B and 16C, from which the current is taken out by the transparent electrode layers 26 and 28. Due to such a configuration, the plurality of photoelectric elements 16 reach the undoped layer 22 by thickening the undoped layer 22 to increase the light absorption rate and thinning the P-type doped layer 18 and the N-type doped layer 20. It is preferable to suppress the absorption of light up to. As a result, the conversion efficiency from light is improved and the amount of current taken out increases.

Subsequently, a case where the color filter structure 14 operates as a sensing mode will be described with reference to FIG. The operation image of the photoelectric element 16 alone is as shown in FIG. As shown in FIG. 4, the color filter structure 14 includes a plurality of TFT elements 70, and the plurality of TFT elements 70 are for light transmission through one of the electrode layers 28 as shown in FIG. 4 (a). First to third photoelectrics for light transmission, which are connected to the first to third photoelectric elements 16A to 16C of the above, or as shown in FIG. 4B, via the other electrode layer 26. It is connected to the elements 16A to 16C. When connected via the electrode layer 28, it is arranged on the array substrate 52 side, and a so-called COA (Color filter on Array) is formed. In either case, each of the TFT elements 70 has a structure held by a substrate 72 such that the drain and source 74 are located on opposite sides of the gate 76 with the channel layer 78 in between. And is connected to the first to third photoelectric elements 16A to 16C via the source 74. The plurality of TFT elements 70 are formed so as to provide a reverse bias to the first to third photoelectric elements 16A to 16C in the sensing mode. The substrate 72 of the TFT element 70 may be used as a heat insulating material or for other purposes.

Further, with reference to FIG. 1, in the sensing mode, the color filter structure 14 arranges colors so that the light emitted from the backlight module 60 is emitted as red light from the display screen 12. At this time, if an object is in contact with or close to the display screen 12, the light from the surrounding environment or the like is blocked by the object and does not enter the display screen 12, but is emitted from the display screen 12. The red light is incident from the display screen 12 as reflected light reflected by the object. For example, when a human finger is in contact with the display screen 12, total reflection occurs in the fingerprint valley and diffuses in the blue / green light region in the fingerprint peak, and the light level differs depending on the fingerprint valley. Reflects on. Then, each of the first to third photoelectric elements 16A to 16C absorbs such reflected light incident from the display screen 12 according to the light absorption characteristics of the semiconductors forming the respective undoped layers 22A to 22C. ..

Further, in the configuration shown in FIG. 4A, one electrode layer 28 is provided, and in the configuration shown in FIG. 4B, the other electrode layer 26 is provided with a reverse bias by the TFT element 70 in the sensing mode. The current generated by the absorption of light as described above is taken out from the first to third photoelectric elements 16A to 16C, and an electric signal corresponding to the strength of the current is generated for each of the taken out currents. At this time, in each of the first to third photoelectric elements 16A to 16C, the capacitance decreases due to the increase in the depletion layer, so that the response time is shortened. Then, each of the generated electric signals is used together with the position information of the photoelectric element 16 from which the current is taken out, and is used for extracting unevenness information of an object that is in contact with or is close to the display screen 12.

Here, the display panel 10 according to the embodiment of the present invention is not limited to the configuration shown in FIGS. 1 to 4, and may have another configuration. For example, the display panel 10 may include components other than the components shown in FIG. 1 at arbitrary positions as long as its function is not hindered. Further, in the color filter structure 14, not all the portions forming the color filter may be replaced with the photoelectric element 16, and the same color resist as the conventional one may be partially used. That is, only a part of the first to fourth photoelectric elements 16A to 16D may be used, and the color resist may be used for the rest. Further, the undoped layer 22D of the fourth photoelectric element 16D forming the black matrix of the color filter structure 14 is not limited to the structure in which the three types of semiconductors as shown in FIG. 2 are stacked, and one type or two types are not limited. , Or may be composed of four or more types of semiconductors. Further, the position of the color filter structure 14 is not limited to between the glass substrate 30 and the liquid crystal 40, and may be arranged at a position adjacent to the array substrate 52 or the glass substrate 54. Further, the light source 60 is not limited to the backlight module, and may be formed of, for example, a self-luminous material. In the case of the backlight module, either the direct type method or the edge light method may be used. good.

Now, according to the embodiment of the present invention having the above configuration, it is possible to obtain the following effects. That is, as shown in FIG. 1, the display panel 10 according to the embodiment of the present invention colors the light emitted from the light source 60 through the color filter structure 14 and emits the light from the display screen 12. The color filter structure 14 is provided with a plurality of photoelectric elements 16 in place of at least a part of the color resist. These plurality of photoelectric elements 16 have a PIN structure in which the P-type dope layer 18 and the N-type dope layer 20 are separated by the undoped layer 22, and at least one of the first to third photoelectric elements 16A to 16C. It contains one type of photoelectric element. In these first to third photoelectric elements 16A to 16C, the undoped layer 22 is formed by three types of semiconductors having different band gaps so as to realize each light transmission pattern of RGB.

That is, for example, in the first photoelectric element 16A, the undoped layer 22A is formed by the semiconductor adjusted to transmit the red light RL, and the second photoelectric element 16B is adjusted to transmit the green light GL. The undoped layer 22B is formed by the semiconductor, and the undoped layer 22C is formed by the semiconductor adjusted so that the third photoelectric element 16C transmits the blue light BL. As a result, the display panel 10 can realize the function of the color filter by adjusting the band gap of the semiconductor forming the undoped layer 22 of the plurality of photoelectric elements 16. Further, in addition to the color arrangement function for the light emitted from the light source 60, various functions using the plurality of photoelectric elements 16 can be realized by the color filter structure 14, so that the utility value of the color filter structure 14 can be realized. It will be possible to improve.
Further, in the display panel 10 according to the embodiment of the present invention, since the light source 60 is a backlight module, an appropriate amount of light can be easily obtained as a display device.

Further, in the display panel 10 according to the embodiment of the present invention, the plurality of photoelectric elements 16 used in the color filter structure 14 include the fourth photoelectric element 16D in addition to the first to third photoelectric elements 16A to 16C. It is included. As shown in FIG. 2, the fourth photoelectric element 16D is formed by stacking three types of semiconductors forming the undoped layers 22A to 22C of the first to third photoelectric elements 16A to 16C to form the undoped layer 22D. Has been done. That is, a semiconductor that absorbs light having a wavelength other than red light RL, a semiconductor that absorbs light having a wavelength other than green light GL, and a semiconductor that absorbs light having a wavelength other than blue light BL are superposed. As a result, a black matrix that blocks light of any wavelength of RGB can be realized by the fourth photoelectric element 16D. Therefore, black is used by using a semiconductor different from the first to third photoelectric elements 16A to 16C. Compared with the case of realizing a matrix, the cost can be suppressed.

Further, in the display panel 10 according to the embodiment of the present invention, as shown in FIG. 1, the color filter structure 14 includes a pair of transparent electrode layers 26, 28, and between the pair of electrode layers 26, 28. A plurality of photoelectric elements 16 are arranged. Therefore, in the portion where the plurality of photoelectric elements 16 are provided instead of the color resist, one of the electrode layers 26, the P-type / N-type dope layer 18/20, the undoped layer 22, and the N-type / P-type dope layer 20 / The structure is such that 18 and the other electrode layer 28 are laminated in this order of description. Further, the color filter structure 14 is configured to be operable as a power generation mode, and in this power generation mode, the photoelectric light for light transmission included in the plurality of photoelectric elements 16 among the first to third photoelectric elements 16A to 16C As shown in FIG. 3, each of the elements 16 absorbs incident light IB and IA from the light source 60 and / or the surroundings. That is, each of the light transmission photoelectric elements 16A to 16C is opposite to the incident light IB from the backlight module 60 that has passed through the transparent electrode layer 28 on the backlight module 60 side as the light source 60 and the backlight module 60. The incident light IA from the surroundings passing through the transparent electrode layer 26 on the display screen 12 side located in, in other words, the incident light IA from the ambient environment in which the display panel 10 incident through the display screen 12 is arranged. The incident light of at least one of the above is absorbed by the semiconductor forming the undoped layer 22.

More specifically, for example, in the first photoelectric element 16A, the undoped layer 22A is formed by a semiconductor whose bandgap is adjusted so as to transmit red light RL, and the semiconductor causes green light GL or blue light BL. Absorbs light with a wavelength other than red light RL. Therefore, the light-transmitting photoelectric elements 16A to 16C absorb light having a wavelength corresponding to the light absorption characteristics of the semiconductor forming each undoped layer 22, and generate electron hole pairs in each undoped layer 22. To generate a built-in electric field. Then, in the power generation mode, the pair of electrode layers 26 and 28 are photovoltaically generated by the separation of electron hole pairs via the P-type dope layer 18 and the N-type dope layer 20 in the photoelectric elements 16A to 16C for light transmission. It is formed so as to draw an electric current from the electric power. As a result, the color filter structure 14 can function like a solar cell to generate electricity by utilizing the light from the light source 60 and / or the light from the surrounding environment, and its utility value can be further improved. It becomes.

In addition, in the display panel 10 according to the embodiment of the present invention, the color filter structure 14 may be configured to be operable as a sensing mode. In this case, the color filter structure 14 further includes a plurality of TFT elements 70, as shown in FIG. The plurality of TFT elements 70 are light-transmitting photoelectric elements included in the plurality of photoelectric elements 16 among the first to third photoelectric elements 16A to 16C via one of the pair of electrode layers 26 and 28. It is connected to 16. Further, in the sensing mode, the color filter structure 14 controls a plurality of photoelectric elements 16 and the like so that the light emitted from the backlight module 60 as the light source 60 is emitted as red light from the display screen 12. Color scheme.

Further, in the sensing mode, the plurality of TFT elements 70 provide a reverse bias to the light transmitting photoelectric elements 16A to 16C of the connection destination, and each of these light transmitting photoelectric elements 16A to 16C is displayed from the display screen 12. It emits as red light and absorbs the reflected light reflected by an object that comes into contact with or is close to the display screen 12. That is, the light-transmitting photoelectric elements 16A to 16C absorb light having a wavelength corresponding to the light absorption characteristics of the semiconductors forming the respective undoped layers 22A to 22C, whereby electrons are absorbed in the respective undoped layers 22A to 22C. It creates a pair of holes to create a built-in electric field. Similarly, in the sensing mode, the pair of electrode layers 26 and 28 take out a current from the photoelectric elements 16A to 16C for light transmission, and generate an electric signal according to the strength of the current for each of the taken out currents.

Here, the reflected light reflected by an object that is in contact with or close to the display screen 12 is reflected at various levels of light and dark due to the reflection characteristics and the scattering characteristics according to the unevenness of the surface of the object. Therefore, the strength of the current taken out from each of the light-transmitting photoelectric elements 16A to 16C changes depending on the level of lightness and darkness of the absorbed reflected light. Therefore, the pair of electrode layers 26, 28 generate an electric signal having a magnitude corresponding to the strength of the current for each current taken out from the photoelectric elements 16A to 16C for light transmission. Then, by adding the position information of the photoelectric element 16 from which the light is taken out to each of these electric signals, it is possible to obtain planar signal information according to the arrangement of the photoelectric elements 16A to 16C for light transmission. As a result, it is possible to obtain information on the unevenness of an object that is in contact with or close to the display screen 12 in a plane, so that it can function like an optical sensor that detects fingerprints and the like, and the utility value of the color filter structure 14 is further improved. It is possible to make it.

On the other hand, as shown in FIG. 1, the photoelectric element 16 according to the embodiment of the present invention has a PIN structure in which the P-type dope layer 18 and the N-type dope layer 20 are separated by the undoped layer 22, and is undoped. The layer 22 is formed of at least one type of semiconductor. The bandgap of at least one type of semiconductor forming the undoped layer 22 is adjusted so as to impart light transmission characteristics having a wavelength in a predetermined range. Therefore, there are three types of semiconductors: a semiconductor adjusted to transmit red light RL, a semiconductor adjusted to transmit green light GL, and a semiconductor adjusted to transmit blue light BL. The three types of photoelectric elements 16A to 16C on which the undoped layer 22 is formed by each of the above can realize a light transmission pattern of RGB, which is the three primary colors.

The undoped layers 22A to 22C of the three types of photoelectric elements 16A to 16C are formed of the following semiconductors. That is, the undoped layer 22A of the first photoelectric element 16A is formed of amorphous silicon having a bandgap adjusted to 1.7 to 1.95 eV, and transmits light having a wavelength of 635 to 730 nm. The undoped layer 22B of the second photoelectric element 16B is formed of gallium phosphide having a bandgap adjusted to 1.8 to 2.26 eV, and transmits light having a wavelength of 550 to 688 nm. Further, the undoped layer 22C of the third photoelectric element 16C is formed of indium gallium nitride having a bandgap adjusted to 2.1 to 3.2 eV, and transmits light having a wavelength of 388 to 590 nm. In this way, the first to third photoelectric elements 16A to 16C that transmit the respective light of RGB can be easily realized.

Further, as shown in FIG. 2, for example, as shown in FIG. 2, a fourth photoelectric element 16D in which an undoped layer 22 is formed so as to block light of any wavelength of RGB by a combination of a plurality of semiconductors whose bandgap is adjusted is black. A matrix can be realized. Therefore, these photoelectric elements 16 can be used as an RGB light transmission pattern and a black matrix in place of the color resist in the color filter structure 14 of the display panel 10. As a result, in such a color filter structure 14, not only the color arrangement but also various functions using the photoelectric element 16 can be realized, so that the utility value of the color filter structure 14 can be improved.

Since the present invention uses a photoelectric element as a color arrangement element having a color filter structure, it can be used not only for a display panel but also for photovoltaic power generation and an optical sensor.

10: Display panel, 12: Display screen, 14: Color filter structure, 16 (16A to 16D): Photoelectric element, 18: P-type dope layer, 20: N-type dope layer, 22 (22A to 22D): Undoped layer, 26, 28: Transparent electrode layer, 60: Light source (backlight module), 70: TFT element

Claims (9)

A photoelectric device having a PIN structure in which a P-type dope layer and an N-type dope layer are separated by an undoped layer.
The undoped layer is formed of at least one type of semiconductor whose bandgap is adjusted to impart light transmission characteristics having a wavelength in a predetermined range, whereby an RGB light transmission pattern and an RGB light transmission pattern are formed in the color filter structure of the display panel. / Or a photoelectric element characterized by being used as a black matrix. A display panel in which the light emitted from a light source is colored by a color filter structure and emitted from a display screen.
The color filter structure is provided with a plurality of photoelectric elements having a PIN structure in which a P-type dope layer and an N-type dope layer are separated by an undoped layer, instead of at least a part of the color resist.
The plurality of photoelectric elements include a first photoelectric element that realizes a red light transmission pattern, a second photoelectric element that realizes a green light transmission pattern, and a third photoelectric element that realizes a blue light transmission pattern. The display is characterized in that the undoped layer is formed of three types of semiconductors having at least one type of photoelectric element, and the first to third photoelectric elements have different band gaps from each other. panel. The display panel according to claim 2, wherein the light source is a backlight module. The plurality of photoelectric elements include a fourth photoelectric element in which the three types of semiconductors are stacked to form the undoped layer, and the black matrix is realized by the fourth photoelectric element. Item 2. The display panel according to Item 2. The color filter structure includes a pair of transparent electrode layers arranged so as to sandwich the plurality of photoelectric elements, and is configured to be operable as a power generation mode.
In the power generation mode,
Among the first to third photoelectric elements, each of the light-transmitting photoelectric elements included in the plurality of photoelectric elements is the incident light from the light source and / or the surroundings that has reached through each of the electrode layers. Is absorbed according to the light absorption characteristics of the semiconductor forming the undoped layer.
The display panel according to any one of claims 2 to 4, wherein the pair of electrode layers draws a current from the light-transmitting photoelectric element. The color filter structure comprises a pair of transparent electrode layers arranged so as to sandwich the plurality of photoelectric elements, and one of the pair of electrode layers, among the first to third photoelectric elements. It includes a plurality of TFT elements connected to a light transmission photoelectric element included in the plurality of photoelectric elements, and is configured to be operable as a sensing mode.
In the sensing mode
The color filter structure is arranged so that the light emitted from the light source is emitted as red light from the display screen.
The plurality of TFT elements provide a reverse bias to the photoelectric element for light transmission.
Each of the light-transmitting photoelectric elements emits light from the display screen and reflects the reflected light by an object in contact with or close to the display screen according to the light absorption characteristics of the semiconductor forming the undoped layer. Absorb and
One of claims 2 to 4, wherein the pair of electrode layers draws a current from the light-transmitting photoelectric element and generates an electric signal according to the strength of the current for each taken-out current. Display panel described in section. The first photoelectric element is characterized in that the undoped layer is formed by amorphous silicon whose bandgap is adjusted to 1.7 to 1.95 eV so as to transmit light having a wavelength of 635 to 730 nm. The display panel according to any one of claims 2 to 6. The second photoelectric element is characterized in that the undoped layer is formed by gallium phosphide whose bandgap is adjusted to 1.8 to 2.26 eV so as to transmit light having a wavelength of 550 to 688 nm. The display panel according to any one of claims 2 to 7. The third photoelectric element is characterized in that the undoped layer is formed by indium gallium nitride having a bandgap adjusted to 2.1 to 3.2 eV so as to transmit light having a wavelength of 388 to 590 nm. The display panel according to any one of claims 2 to 8.

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