Patent Description:
In the related art, display apparatuses refer to output apparatuses displaying visual information converted from received or stored image information to users and have been widely used in various application fields such as individual homes or places of business.

For example, the display apparatuses may be monitor devices connected to personal computers or server computers, portable computer devices, navigation devices, televisions (TVs), Internet Protocol televisions (IPTVs), portable terminals, such as smartphones, tablet personal computers (PCs), personal digital assistants (PDAs), or cellular phones, or various display apparatuses used to play advertisements or movies in the industrial field, or various types of audio/video systems.

The display apparatuses may display an image using various types of display panels. For example, the display apparatuses may include a light emitting diode (LED) panel, an organic light emitting diode (OLED) panel, a liquid crystal display (LCD) panel, and the like.

Among various display panels, a micro LED panel using the light emitting diodes having a size of <NUM> (micrometer) * <NUM> or less have been recently developed.

<CIT> describes display panels and methods of manufacture for down converting a peak emission wavelength of a pump LED within a subpixel with a quantum dot layer.

An aspect of the present disclosure is to provide a display apparatus including a plurality of micro LEDs.

Another aspect of the present disclosure is to minimize a wavelength deviation of light emitted from a plurality of pixels included in a display apparatus.

Another aspect of the present disclosure is to minimize a wavelength deviation of light emitted from a plurality of micro LEDs included in the display apparatus.

There is provided a display apparatus in accordance with claim <NUM>. Other aspects of the invention are set forth in the dependent claims.

According to an aspect of an embodiment, it is possible to provide a display apparatus including a plurality of micro LEDs.

According to another aspect of an embodiment, it is possible to minimize a wavelength deviation of light emitted from a plurality of pixels included in a display apparatus.

According to another aspect of an embodiment, it is possible to minimize a wavelength deviation of light emitted from a plurality of micro LEDs included in a display apparatus.

Like reference numerals refer to like elements throughout the specification. Not all elements of embodiments of the disclosure will be described, and description of what are commonly known in the art or what overlap each other in the embodiments will be omitted. The terms as used throughout the specification, such as "~ part," "~ module," "~ member," "~ block," etc., may be implemented in software and/or hardware, and a plurality of "~ parts," "~ modules," "~ members," or "~ blocks" may be implemented in a single element, or a single "~ part," "~ module," "~ member," or "~ block" may include a plurality of elements.

It will be understood that when an element is referred to as being "connected" to another element, it can be directly or indirectly connected to the other element, wherein the indirect connection includes "connection" via a wireless communication network.

Also, when a part "includes" or "comprises" an element, unless there is a particular description contrary thereto, the part may further include other elements, not excluding the other elements.

Further, when it is stated that a layer is "on" another layer or substrate, the layer may be directly on another layer or substrate or a third layer may be disposed therebetween.

It will be understood that, although the terms first, second, third, etc., may be used herein to describe various elements, it should not be limited by these terms. These terms are only used to distinguish one element from another element.

An identification code is used for the convenience of the description but is not intended to illustrate the order of each step. Each of the steps may be implemented in an order different from the illustrated order unless the context clearly indicates otherwise.

The expression "at least one of A, B and C" should be interpreted to include only A, only B, only C, both A and B, both B and C, both C and A, or all of A, B and C.

Hereinafter, the operation principles and embodiments of the disclosure will be described with reference to the accompanying drawings.

<FIG> is a view illustrating an appearance of a display apparatus according to an embodiment.

A display apparatus <NUM> is an apparatus capable of processing an image signal received from the outside (e.g., external image source) and visually displaying the processed image. As illustrated in <FIG>, the display apparatus <NUM> may be implemented as a TV, but the embodiment of the display apparatus <NUM> is not limited thereto. For example, the display apparatus <NUM> may be implemented as a monitor of a computer, or may be included in a navigation terminal device or various portable terminal devices. Here, the portable terminal devices may be a desktop computer, a laptop computer, a smartphone, a tablet personal computer (PC), a wearable computing device, or a personal digital assistant (PDA).

In addition, the display apparatus <NUM> may be a large format display (LFD) installed outdoors such as on a building roof or at a bus stop. The outdoors is not necessarily limited to the outside, but should be understood as a concept including a place where a large number of people can go in and out, even an area such as a subway station, a shopping mall, a movie theater, a company, a store, etc..

The display apparatus <NUM> may receive a video signal and an audio signal from various content sources, and may output video and audio corresponding to the video signal and the audio signal. For example, the display apparatus <NUM> may receive television broadcast content through a broadcast receiving antenna or a cable, receive content from a content reproduction device, or receive the content from a content providing server of a content provider.

As illustrated in <FIG>, the display apparatus <NUM> may include a main body <NUM> accommodating a plurality of components for displaying an image I and a screen S provided on one surface of the main body <NUM> to display the image I.

The main body <NUM> may form an appearance of the display apparatus <NUM> and the component for displaying the image I by the display apparatus <NUM> may be provided in the inside of the main body <NUM>. The main body <NUM> illustrated in <FIG> may be in the form of a flat plate, but the shape of the main body <NUM> is not limited to that illustrated in <FIG>. For example, the main body <NUM> may have a shape in which left and right ends protrude forward and a center part is curved so as to be concave.

The screen S may be formed on the front surface of the main body <NUM>, and the screen S may display the image I as visual information. For example, a still image or a moving image may be displayed on the screen S, and a two-dimensional plane image or a three-dimensional stereoscopic image may be displayed.

A plurality of pixels P may be formed on the screen S, and the image I displayed on the screen S may be formed by a combination of light emitted from the plurality of pixels P. For example, the single image I may be formed on the screen S by combining the light emitted by the plurality of pixels P with a mosaic.

Each of the plurality of pixels P may emit the light of various brightness and various colors.

Each of the plurality of pixels P may include a configuration (for example, an organic light emitting diode) capable of emitting the light directly in order to emit the light of various brightness, or a configuration (for example, a liquid crystal panel) capable of transmitting or blocking the light emitted by a backlight unit or the like.

In order to emit the light of various colors, each of the plurality of pixels P may include subpixels PR, PG, and PB.

The subpixels PR, PG, and PB may emit light. The red subpixel PR may emit red light, the green subpixel PG may emit green light, and the blue subpixel PB may emit blue light. The red subpixel PR emits red light having a wavelength of approximately <NUM> (nanometer, <NUM> billionth of a meter) to <NUM>, the green subpixel PG emits green light having a wavelength of approximately <NUM> to <NUM>, and the blue subpixel PB emits blue light having a wavelength of approximately <NUM> to <NUM>.

By the combination of the red light of the red subpixel PR, the green light of the green subpixel PG, and the blue light of the blue subpixel PB, each of the plurality of pixels P may emit the light of various brightness and various colors.

The screen S may be provided in the flat plate shape as illustrated in <FIG>. However, the shape of the screen S is not limited to that illustrated in <FIG>. It may be provided in a shape in which both ends protrude forward and the center portion is curved so as to be concave according to the shape of the main body <NUM>.

The display apparatus <NUM> may include various types of display panels for displaying the image. For example, the display apparatus <NUM> may include an emissive display panel for displaying the image using an element that is self-luminous. The emissive display panel may include a light emitting diode (LED) panel or an organic light emitting diode (OLED) panel. In addition, the display apparatus <NUM> may include a non-emissive display panel for displaying the image by passing or blocking light emitted from a light source (backlight unit). The non-emissive display panel may include a liquid crystal display (LCD) panel.

Hereinafter, the display apparatus <NUM> including the LED panel is described.

<FIG> is an exploded view illustrating a display apparatus according to an embodiment.

As illustrated in <FIG>, various components for generating the image I on the screen S may be provided in the main body <NUM>.

For example, the main body <NUM> may include a light emitting diode panel <NUM> for emitting light forward to generate the image, a control assembly <NUM> mounted with a configuration for controlling an operation of the light emitting diode panel <NUM>, a power supply assembly <NUM> mounted with a configuration for supplying power to the light emitting diode panel <NUM> and the control assembly <NUM>, a bottom chassis <NUM> for supporting/fixing the control assembly <NUM> and the power supply assembly <NUM>, and a bezel <NUM> and a rear cover <NUM> for preventing the light emitting diode panel <NUM>, the control assembly <NUM>, and the power supply assembly <NUM> from being exposed to the outside.

The light emitting diode panel <NUM> may include a plurality of light emitting elements 103a, and the plurality of light emitting elements 103a may each include a light emitting diode. The light emitting diode may represent a semiconductor element that emits light of a predetermined wavelength when power is supplied. The light emitting diode has a polarity like a normal diode, and when a voltage is applied between a cathode and an anode, a current passing through the light emitting diode flows and emits light. The light emitting diode may have various sizes, and the light emitting diode having a size of <NUM> (micrometer) * <NUM> or less may be called a micro light emitting diode. The light emitting diode panel <NUM> may include, for example, the micro light emitting diode.

Each of the plurality of light emitting elements 103a may emit light of various colors and various brightness. The light emitting diodes included in each of the plurality of light emitting elements 103a may emit light having different wavelengths (different colors) according to a constituent material. For example, the light emitting diode including aluminum gallium arsenide (AlGaAs), gallium arsenide phosphorus (GaAsP), and gallium phosphide (GaP) may emit red light having a wavelength of approximately <NUM> to <NUM>, the light emitting diode indium gallium nitride (InGaN) may emit green light having a wavelength of approximately <NUM> to <NUM>, and the light emitting diode including gallium nitride (GaN) may emit blue light having a wavelength of approximately <NUM> to <NUM>.

In addition, the plurality of light emitting elements 103a may emit light of different intensities according to the magnitude of the supplied current. The light emitting diodes included in each of the plurality of light emitting elements 103a may emit light having a strong intensity as a driving current supplied increases.

The image may be formed by the combination of light emitted from each of the plurality of light emitting elements 103a. For example, the image may be formed by the combination of the red light emitted from the red light emitting diode, the green light emitted from the green light emitting diode, and the blue light emitted from the blue light emitting diode.

The front surface of the light emitting diode panel <NUM> (surface on which light is emitted) may form the screen S of the display apparatus <NUM> described above, and each of the plurality of light emitting elements 103a may form the pixels P or the subpixels PR, PG, and PB described above.

On one side of the light emitting diode panel <NUM>, a cable 103b for transmitting image data to the light emitting diode panel <NUM>, and a display driver integrated circuit (DDI) <NUM> (hereinafter referred to as 'driver IC') for processing digital image data and outputting an analog image signal may be provided.

The cable 103b may electrically connect between the control assembly <NUM> and the power assembly <NUM> described above and the driver IC <NUM>, and may also electrically connect between the driver IC <NUM> and the light emitting diode panel <NUM>. The cable 103b may include a flexible flat cable or a film cable that can be bent.

The driver IC <NUM> may receive the image data and the power from the control assembly <NUM> and the power supply assembly <NUM> through the cable 103b, and may supply the image signal and a driving current to the light emitting diode panel <NUM> through the cable 103b.

The cable 103b and the driver IC <NUM> may be integrally implemented as a film cable, a chip on film (COF), a tape carrier packet (TCP), or the like. In other words, the driver IC <NUM> may be disposed on the cable 103b. However, the present disclosure is not limited thereto, and the driver IC <NUM> may be disposed on the light emitting diode panel <NUM> or the control assembly <NUM>.

The control assembly <NUM> may include a control circuit that controls the operation of the light emitting diode panel <NUM>. The control circuit may process the image data received from an external content source and transmit the image data to the light emitting diode panel <NUM> so that the plurality of light emitting elements 103a emit light having different colors and different brightness.

The power assembly <NUM> may supply the power to the light emitting diode panel <NUM> so that the plurality of light emitting elements 103a emit light having different colors and different brightness.

The control assembly <NUM> and the power supply assembly <NUM> may be implemented with a printed circuit board and various circuits mounted on the printed circuit board. For example, the power supply circuit may include a capacitor, a coil, a resistance element, a microprocessor, and the like, and a power supply circuit board on which they are mounted. Further, the control circuit may include a memory, the microprocessor, and a control circuit board on which they are mounted.

<FIG> is a view illustrating a light emitting diode panel and a driver IC included in a display apparatus according to an embodiment, and <FIG> is a view illustrating an equivalent circuit of a light emitting diode panel included in a display apparatus according to an embodiment.

As illustrated in <FIG> and <FIG>, the display apparatus <NUM> may include a data driver 104a, a scan driver 104b, and the light emitting diode panel <NUM>.

The light emitting diode panel <NUM> may include the plurality of pixels P, and each of the plurality of pixels P may include the red subpixel PR, the green subpixel PG, and the blue subpixel PB.

The plurality of subpixels PR, PG, and PB may be arranged in two-dimensions on the light emitting diode panel <NUM>. For example, the plurality of subpixels PR, PG, and PB may be arranged in a matrix on the light emitting diode panel <NUM>. In other words, the plurality of subpixels PR, PG, and PB may be arranged in rows and columns.

A plurality of data lines D<NUM>, D<NUM> and D<NUM> and a plurality of scan lines S<NUM> and S<NUM> may be provided between the plurality of subpixels PR, PG, and PB. The plurality of scan lines S<NUM> and S<NUM> may be connected to the scan driver 104b, and the plurality of data lines D<NUM>, D<NUM> and D<NUM> may be connected to the data driver 104a.

The data driver 104a may receive red/green/blue image data (hereinafter referred to as "RGB image data") and a data control signal from the control circuit of the control assembly <NUM>, and may output the RGB image data to the light emitting diode panel <NUM> according to the data control signal. Particularly, the data driver 104a may receive digital RGB image data, convert the digital RGB image data to an analog RGB image signal, and output the analog RGB image signal to the light emitting diode panel <NUM>.

Each of a plurality of outputs provided in the data driver 104a may be connected to the plurality of data lines D<NUM>, D<NUM>, and D<NUM> of the light emitting diode panel <NUM>. The data driver 104a may output the RGB image signal to each of the plurality of subpixels PR, PG, and PB through the plurality of data lines D<NUM>, D<NUM>, and D<NUM>. For example, the data driver 104a may simultaneously output the RGB image signal to each of the plurality of subpixels PR, PG, and PB included in one row on the light emitting diode panel <NUM>.

The scan driver 104b may receive a scan control signal from the control circuit of the control assembly <NUM>, and may activate the plurality of subpixels PR, PG, and PB included in any one of the plurality of rows according to the scan control signal. For example, the scan driver 104b may output an activation signal to any one of the plurality of scan lines S<NUM> and S<NUM> according to the scan control signal.

The scan driver 104b may select any one of the plurality of scan lines S<NUM> and S<NUM> so that the RGB image is provided to the subpixels PR, PG, and PB belonging to an appropriate row among the plurality of subpixels PR, PG, and PB arranged in a matrix form according to the scan control signal. Also, the data driver 104a may output the RGB image signal through the plurality of data lines D<NUM>, D<NUM>, and D<NUM>, and the RGB image signal output by the data driver 104a may be provided to the subpixels PR, PG, and PB belonging to the row selected by the scan driver 104b.

As such, the data driver 104a and the scan driver 104b may sequentially provide the RGB image signals to the plurality of subpixels PR, PG, and PB included in the light emitting diode panel <NUM>.

Each of the plurality of subpixels PR, PG, and PB may include scan transistors <NUM>, <NUM>, and <NUM>, driving transistors <NUM>, <NUM>, and <NUM>, storage capacitors <NUM>, <NUM>, and <NUM>, and light emitting elements <NUM>, <NUM>, and <NUM>.

The scan transistors <NUM>, <NUM>, and <NUM> may be thin film transistors (TFT) including a control terminal (Gate) T1 and first and second input/output terminals (Source, Drain) T2 and T3. The scan transistors <NUM>, <NUM>, and <NUM> may allow current flow between the first and second input/output terminals T2 and T3 according to the control signal input to the control terminal T1 (turn-on), or may block the current flow between the first and second input/output terminals T2 and T3 (turn-off).

The scan transistors <NUM>, <NUM>, and <NUM> may be turned on or off according to the scan control signal output from the scan driver 104b. For example, the control terminals T1 of the scan transistors <NUM>, <NUM>, <NUM> may be connected to the scan lines S<NUM> and S<NUM>, and the first input/output terminal T2 of the scan transistors <NUM>, <NUM>, and <NUM> may be connected to the data lines D<NUM>, D<NUM>, and D<NUM>.

When the activation signal is received from the scan driver 104b to the control terminal T1, the scan transistors <NUM>, <NUM>, and <NUM> may be turned on. The scan transistors <NUM>, <NUM>, and <NUM> may receive the RGB image signals of the data lines D<NUM>, D<NUM>, and D<NUM> through the first input/output terminal T2 and output the RGB image signals of the data lines D<NUM>, D<NUM>, and D<NUM> through the second input/output terminal T3. Also, when the activation signal is not received from the scan driver 104b to the control terminal T1, the scan transistors <NUM>, <NUM>, and <NUM> may be turned off.

The driving transistors <NUM>, <NUM>, and <NUM> may be thin film transistors including a control terminal T4 and first and second input/output terminals T5 and T6. The driving transistors <NUM>, <NUM>, and <NUM> may allow the current flow between the first and second input/output terminals T5 and T6 according to the control signal input to the control terminal T4 (turn on), or may block the current flow between the first and second input/output terminals T5 and T6 (turn-off).

The driving transistors <NUM>, <NUM>, and <NUM> may output the driving current to the light emitting elements <NUM>, <NUM>, and <NUM> according to the RGB image signal output from the data driver 104a and passing through the scan transistors <NUM>, <NUM>, and <NUM>.

For example, the control terminal T4 of the driving transistors <NUM>, <NUM>, and <NUM> may be connected to the second input/output terminal T3 of the scan transistors <NUM>, <NUM>, and <NUM>, the first input/output terminal T5 of the driving transistors <NUM>, <NUM>, and <NUM> may be connected to a power supply VDD, and the second input/output terminal T6 of the scan transistors <NUM>, <NUM>, and <NUM> may be connected to the light emitting elements <NUM>, <NUM>, and <NUM>. The driving transistors <NUM>, <NUM>, and <NUM> may control a magnitude of current flowing between the first input/output terminal T5 and the second input/output terminal T6 according to the RGB image signal input to the control terminal T4. In other words, the driving transistors <NUM>, <NUM>, and <NUM> may control the magnitude of current supplied to the light emitting elements <NUM>, <NUM>, and <NUM> according to the RGB image signal.

The storage capacitors <NUM>, <NUM>, and <NUM> store the RGB image signals input to the driving transistors <NUM>, <NUM>, and <NUM> through the scan transistors <NUM>, <NUM>, and <NUM> from the data driver 104a, and may output a voltage corresponding to the RGB image signals. For example, the storage capacitors <NUM>, <NUM>, and <NUM> may be connected between the control terminal T4 of the driving transistors <NUM>, <NUM>, and <NUM> and the second input/output terminal T6, and the voltage corresponding to the RGB image signal may be output between the control terminal T4 and the second input/output terminal T6 of the driving transistors <NUM>, <NUM>, and <NUM>. The driving transistors <NUM>, <NUM>, and <NUM> may control the magnitude of current supplied to the light emitting elements <NUM>, <NUM>, and <NUM> according to the voltage of the RGB image signal stored in the storage capacitors <NUM>, <NUM>, and <NUM>.

The light emitting elements <NUM>, <NUM>, and <NUM> may output light of different intensities according to the magnitude of the current supplied from the driving transistors <NUM>, <NUM>, and <NUM>. In other words, the light emitting elements <NUM>, <NUM>, and <NUM> may output light of different intensities according to the RGB image signal output from the data driver 104a.

In addition, the light emitting elements <NUM>, <NUM>, and <NUM> may emit light having different wavelengths (different colors) depending on the constituent material. For example, the light emitting diode panel <NUM> may include the red light emitting element <NUM> emitting red light, the green light emitting element <NUM> emitting green light, and the blue light emitting element <NUM> emitting blue light.

The red light emitting element <NUM>, the green light emitting element <NUM> and the blue light emitting element <NUM> may be provided at positions corresponding to the red subpixel PR, the green subpixel PG, and the blue subpixel PB, respectively.

The red light emitting element <NUM> may output red light having different intensities according to a red image signal (hereinafter referred to as 'R image signal') output from the data driver 104a, the green light emitting element <NUM> may output green light having different intensities according to a green image signal (hereinafter, referred to as 'G image signal') output from the data driver 104a, and the blue light emitting element <NUM> may output blue light having different intensities according to a blue image signal (hereinafter, referred to as 'B image signal') output from the data driver 104a.

The light emitting elements <NUM>, <NUM>, and <NUM> may include the micro light emitting diodes each having the size of <NUM> * <NUM> or less.

As described above, the display apparatus <NUM> may include the light emitting diode panel <NUM> having the red light emitting element <NUM>, the green light emitting element <NUM>, and the blue light emitting element <NUM>.

The red light emitting element <NUM>, the green light emitting element <NUM> and the blue light emitting element <NUM> may have various structures to emit red light, green light, and blue light, respectively.

Hereinafter, the structures of the red light emitting element <NUM>, the green light emitting element <NUM> and the blue light emitting element <NUM> may be described.

<FIG> is a view illustrating an example of light emitting elements included in a display apparatus according to an embodiment. <FIG> is a view illustrating a structure of a red light emitting element included in the display apparatus illustrated in <FIG> and a spectrum of light output from the red light emitting element. <FIG> is a view illustrating a structure of a green light emitting element included in the display apparatus illustrated in <FIG> and a spectrum of light output from the green light emitting element. <FIG> is a view illustrating a structure of a blue light emitting element included in the display apparatus illustrated in <FIG> and a spectrum of light output from the blue light emitting element.

<FIG> illustrates one pixel included in the display apparatus <NUM>, and <FIG> illustrates cross section A-A' illustrated in <FIG>.

As illustrated in <FIG>, the pixels P may include the red subpixel PR, the green subpixel PG, and the blue subpixel PB. The red subpixel PR, the green subpixel PG, and the blue subpixel PB may be arranged side by side.

In addition, the red subpixel PR may include the red light emitting element <NUM>, the green subpixel PG may include the green light emitting element <NUM>, and the blue subpixel PB may include the blue light emitting element <NUM>.

As illustrated in <FIG> and <FIG>, the red light emitting element <NUM> may include a first light emitting diode <NUM>, a red light conversion layer <NUM>, and a red filter <NUM>.

The first light emitting diode <NUM> may include a cathode terminal <NUM> and an anode terminal <NUM>, and may be connected to a driving circuit through the cathode terminal <NUM> and the anode terminal <NUM>. The driving circuit may include the scan transistors <NUM>, <NUM>, and <NUM>, the driving transistors <NUM>, <NUM>, and <NUM>, and the storage capacitors <NUM>, <NUM>, and <NUM> as illustrated in <FIG> above. The first light emitting diode <NUM> may receive the driving current from the driving circuit through the cathode terminal <NUM> and the anode terminal <NUM> and emit light. For example, as illustrated in <FIG>, the first light emitting diode <NUM> may emit the light having a maximum intensity at a wavelength λB1 similar to a blue wavelength (hereinafter referred to as 'light having the wavelength similar to the blue wavelength').

The red light conversion layer <NUM> may absorb light emitted from the first light emitting diode <NUM>, and may emit light having a maximum intensity at a red wavelength λR (hereinafter referred to as 'light having the red wavelength'). In other words, the red light conversion layer <NUM> may convert light having the wavelength λB1 similar to the blue wavelength to light having the red wavelength λR.

For example, the red light conversion layer <NUM> may include quantum dots for changing the wavelength of incident light. The quantum dots may refer to small sphere-shaped semiconductor particles a size of a nanometer (nm, <NUM>,<NUM>,<NUM>,000ths of a meter), and may have a size of approximately <NUM> to <NUM>. The quantum dots may be composed of a core composed of cadmium selenite (CdSe), cadmium telluride (CdTe), cadmium sulfide (CdS), or the like, and a shell composed of zinc sulfide (ZnS).

The quantum dots may have different optical characteristics than bulk materials of the same material. For example, the quantum dots may emit light when a voltage is applied, or emit light of a specific wavelength when light is incident. In other words, the quantum dots may output light having a wavelength different from that of the incident light.

The wavelength of the light output by the quantum dots may vary depending on the size of the quantum dots. An energy band gap between a valence band and a conduction band may vary depending on the size of the quantum dots, and the wavelength of light emitted from the quantum dots may vary depending on the size of the quantum dots.

For example, in the case of cadmium selenite (CdSe) quantum dots, when a diameter of the quantum dots is approximately <NUM> or less, the energy band gap may be increased by a quantum confinement effect. As the energy band gap increases, the wavelength of light emitted from the quantum dots may be shortened (a frequency of light emitted from the quantum dots may be increased). In other words, the cadmium selenite (CdSe) bulk may emit the red light, but the cadmium selenite (CdSe) quantum dots may emit yellow light, the green light, and the blue light as its size decreases.

As such, the quantum dots may emit light of different wavelengths (different colors) depending on the size. For example, the quantum dots with a diameter of approximately <NUM> may emit approximately blue light, and the quantum dots with a diameter of approximately <NUM> may emit approximately green light. In addition, the quantum dots with a diameter of approximately <NUM> may emit approximately red light.

The red light conversion layer <NUM> may include the quantum dots capable of emitting the red light. For example, the red light conversion layer <NUM> may include the quantum dots having the diameter of approximately <NUM>.

In addition, the red light conversion layer <NUM> may include a red fluorescent material that converts light having the wavelength λB1 similar to the blue wavelength to light having the red wavelength λR.

As illustrated in <FIG>, the light emitted from the red light conversion layer <NUM> may include light emitted from the first light emitting diode <NUM> and passing through the red light conversion layer <NUM> (light having the wavelength similar to the blue red wavelength), and light whose wavelength is converted by the red light conversion layer <NUM> (light having the blue wavelength).

The red filter <NUM> may pass light having the red wavelength λR among the incident light, and may block light having a wavelength different from the red light. Particularly, the red filter <NUM> may pass light having the red wavelength λR and block light having the wavelength λB1 similar to the blue wavelength.

The red filter <NUM> is not limited to an optical filter that passes light having the red wavelength λR. For example, as illustrated in <FIG>, the red filter <NUM> may include the optical filter that blocks light (e.g., blue light) having the wavelength shorter than the red wavelength λR and passes light having the wavelength longer than the red wavelength λR.

A part of the light (light of the color similar to blue) emitted from the first light emitting diode <NUM> included in the red light emitting element <NUM> may be changed to red light while passing through the red light conversion layer <NUM>, and the other part of the light emitted from the first light emitting diode <NUM> (light of the color similar to blue) may be blocked by the red filter <NUM>. As a result, as illustrated in <FIG>, the red light emitting element <NUM> may emit light having the maximum intensity at the red wavelength λR.

At this time, the wavelength deviation of the red light emitted from the red light emitting element <NUM> may be very small (may be approximately <NUM> or less). As described above, the blue light emitted from the first light emitting diode <NUM> may be converted into red light by the red light conversion layer <NUM>, and the wavelength of light emitted from the red light conversion layer <NUM> may depend on the size of the quantum dots. The size of the red quantum dots may be adjusted very precisely, and the variation in size between the quantum dots is very small. Therefore, the wavelength deviation of the light emitted from the red light conversion layer <NUM> may also be very small.

As illustrated in <FIG> and <FIG>, the green light emitting element <NUM> may include a second light emitting diode <NUM>, a green light conversion layer <NUM>, and a green filter <NUM>.

The second light emitting diode <NUM> may receive the driving current from the driving circuit through a cathode terminal <NUM> and an anode terminal <NUM>. For example, as illustrated in <FIG>, the second light emitting diode <NUM> may emit light having the wavelength λB1 similar to the blue wavelength.

The green light conversion layer <NUM> may absorb light (light having the wavelength similar to the blue wavelength) emitted from the second light emitting diode <NUM>, and may emit light having the maximum intensity at a green wavelength λG (hereinafter referred to as 'light having the green wavelength'). In other words, the red light conversion layer <NUM> may convert light having the wavelength λB1 similar to the blue wavelength into light having the green wavelength λG.

The green light conversion layer <NUM> may include the quantum dots capable of emitting the green light. For example, the green light conversion layer <NUM> may include the quantum dots having the diameter of approximately <NUM>.

In addition, the green light conversion layer <NUM> may include a green fluorescent material that converts light having the wavelength λB1 similar to the blue wavelength to light having the green wavelength λG.

As illustrated in <FIG>, the light emitted from the green light conversion layer <NUM> may include light emitted from the second light emitting diode <NUM> and passing through the green light conversion layer <NUM> (light having the wavelength similar to the blue wavelength), and light whose wavelength is converted by the green light conversion layer <NUM> (light having the green wavelength).

The green filter <NUM> may pass light having the green wavelength λG among the incident light, and may block light having a wavelength different from the green light. Particularly, the green filter <NUM> may pass light having the green wavelength λG whose wavelength is converted by the green light conversion layer <NUM>, and may block light having the wavelength λB1 similar to the blue wavelength passed through the green light conversion layer <NUM>.

The green filter <NUM> is not limited to the optical filter that passes the wavelength corresponding to green light. For example, as illustrated in <FIG>, the green filter <NUM> may include the optical filter that blocks light (e.g., blue light) having the wavelength shorter than the green wavelength λG and passes light having the wavelength longer than the green wavelength λG.

A part of the light of the color similar to blue emitted from the second light emitting diode <NUM> included in the green light emitting element <NUM> may be changed to green light while passing through the green light conversion layer <NUM>, and the other part of the light may be blocked by the green filter <NUM>. As a result, as illustrated in <FIG>, the green light emitting element <NUM> may emit light having the maximum intensity at the green wavelength λG.

At this time, the wavelength deviation of the green light emitted from the green light emitting element <NUM> may be very small (may be approximately <NUM> or less). This is because the size of the green quantum dots may be adjusted very precisely, and the variation in the size between the quantum dots is very small.

As illustrated in <FIG> and <FIG>, the blue light emitting element <NUM> may include a third light emitting diode <NUM>, a transparent resin layer <NUM>, and a blue filter <NUM>.

The third light emitting diode <NUM> may receive the driving current from the driving circuit through a cathode terminal <NUM> and an anode terminal <NUM>. For example, as illustrated in <FIG>, the third light emitting diode <NUM> may emit light having the wavelength λB1 similar to the blue wavelength.

The transparent resin layer <NUM> may pass light emitted from the third light emitting diode <NUM> (light having the wavelength similar to the blue wavelength). The transparent resin layer <NUM> may be composed of various transparent resins such as PC (Polycarbonate), PES (Polyether Sulfone), PMMA (Polymethyl Methacrylate), PVA (Polyvinyl alcohol), and PI (Polyimide).

As illustrated in <FIG>, the blue filter <NUM> may pass light having the blue wavelength λB among the incident light and block light having a wavelength different from the blue light. Particularly, the blue filter <NUM> may pass light having the blue wavelength λB among light emitted from the third light emitting diode <NUM> and block light having the wavelength λB1 similar to the blue wavelength.

The blue filter <NUM> may reduce the wavelength deviation of the light (light having the wavelength similar to the blue wavelength) emitted from the third light emitting diode <NUM>.

The wavelength deviation of the light emitted from the third light emitting diode <NUM> may be relatively large (approximately <NUM> or more). As the light emitting diode, a mixed semiconductor such as gallium arsenide (GaAs), indium gallium nitride (InGaN), and gallium nitride (GaN) may be used. The light emitting diode may be manufactured by growing a first epitaxial layer containing a first impurity on a substrate and then growing a second epitaxial layer containing a second impurity. The light may be emitted at a boundary (PN junction) between the first epitaxial layer including the first impurity and the second epitaxial layer including the second impurity.

At this time, the wavelength of the light emitted from the light emitting diode may be changed according to a mixing ratio of base materials Ga, As, In, N, etc., a concentration of the first impurity contained in the first epitaxial layer and/or a concentration of the second impurity contained in the second epitaxial layer. It is known that the blue light emitting diode has the wavelength deviation of approximately <NUM> or more due to a variation in the concentration of the first impurity and/or a variation in the concentration of the second impurity.

The light emitted from the third light emitting diode <NUM> (light having the wavelength similar to the blue wavelength) has the wavelength deviation of approximately <NUM> or more, and thus, the color gamut of the display apparatus <NUM> may be reduced after correction of the wavelength deviation to increase display color uniformity.

In order to reduce the wavelength deviation of the blue light emitted from the third light emitting diode <NUM>, the third light emitting diode <NUM> outputs light having a maximum intensity at a wavelength (approximately <NUM> to <NUM>) shorter than the blue wavelength (approximately <NUM>). The blue filter <NUM> blocks light having a wavelength shorter than the blue wavelength (approximately <NUM>).

As a result, the light passing through the blue filter <NUM> may have the maximum intensity at approximately the blue wavelength (approximately <NUM>). In addition, the wavelength deviation of the light passing through the blue filter <NUM> may be reduced to approximately <NUM> or less. In other words, the wavelength deviation of the blue light emitted from the blue light emitting element <NUM> may be approximately <NUM> or less.

Hereinafter, reducing the wavelength deviation of the blue light emitted from the blue light emitting element <NUM> will be described in more detail.

<FIG> and <FIG> are views illustrating a wavelength deviation of light output from a blue light emitting diode included in the display apparatus illustrated in <FIG>. <FIG>, <FIG>, and <FIG> are views illustrating a wavelength deviation of light output from a blue light emitting element included in the display apparatus illustrated in <FIG>.

As illustrated in <FIG>, a plurality of blue light emitting diodes <NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM>,. , and <NUM>-n may be manufactured on a single wafer W. For example, the blue light emitting diodes <NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM>,. , and <NUM>-n may be composed of gallium nitride (GaN), and may emit light having the maximum intensity at the wavelength similar to the blue wavelength.

Particularly, a PN junction may be formed by growing the first epitaxial layer containing the first impurity on the wafer W forming the substrate and then growing the second epitaxial layer containing the second impurity. A PN junction diode may be manufactured by cutting the wafer W on which the PN junction is formed to a predetermined size, and the PN junction diode may become the blue light emitting diode capable of emitting the light.

For example, by cutting the wafer W on which the PN junction is formed, the first blue light emitting diode <NUM>-<NUM>, the second blue light emitting diode <NUM>-<NUM>, the third blue light emitting diode <NUM>-<NUM>, and the n-th blue light emitting diode <NUM>-n from the single wafer W may be manufactured.

At this time, depending on the position in the single wafer W, the mixing ratio of the base materials Ga and N, the concentration of the first impurity contained in the substrate and/or the concentration of the second impurity contained in the second epitaxial layer may be different from each other. In addition, the wavelength of light emitted from the light emitting diode may change according to the mixing ratio of the base materials Ga and N, the concentration of the first impurity contained in the first epitaxial layer and/or the concentration of the second impurity contained in the second epitaxial layer.

As a result, the blue light emitting diodes <NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM>,. , and <NUM>-n manufactured on the single wafer W may emit light of different wavelengths. In other words, the wavelength deviation of the light emitted from the blue light emitting diodes <NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM>,. , and <NUM>-n manufactured on the single wafer W may be generated. It is known that the wavelength deviation between the blue light emitting diodes <NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM>,. , and <NUM>-n is approximately <NUM>.

For example, as illustrated in <FIG>, a wavelength λ1 of light emitted from the first blue light emitting diode <NUM>-<NUM>, a wavelength λ2 of light emitted from the second blue light emitting diode <NUM>-<NUM>, a wavelength λ3 of light emitted from the third blue light emitting diode <NUM>-<NUM>, and a wavelength λn of light emitted from the n-th blue light emitting diode <NUM>-n manufactured by the single wafer W may be different from each other.

In addition, the deviation between the wavelengths λ1, λ2, λ3,. , and λn of light emitted from the first to n-th blue light emitting diodes <NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM>,. , and <NUM>-n may be approximately <NUM>. Particularly, the first to n-th blue light-emitting diodes <NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM>,. , and <NUM>-n may emit light having the wavelength of <NUM> to <NUM>.

As such, the plurality of blue light emitting diodes <NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM>,. , and <NUM>-n manufactured by the single wafer W may emit light having the wavelength similar to blue, and the deviation may exist between the wavelengths of light emitted from the plurality of blue light emitting diodes <NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM>,. , and <NUM>-n. In addition, the light emitted from the plurality of blue light emitting diodes <NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM>,. , and <NUM>-n may have any wavelength of <NUM> to <NUM>.

In addition, the display apparatus <NUM> may include the plurality of blue light emitting elements <NUM>, and the plurality of blue light emitting elements <NUM> may include the plurality of blue light emitting diodes <NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM>,. , and <NUM>-n and a plurality of the blue filters <NUM>, respectively.

The blue filter <NUM> may pass light having approximately the blue wavelength or light having the wavelength longer than approximately the blue wavelength λB, and may block light having the wavelength shorter than approximately the blue wavelength λB.

For example, the blue filter <NUM> may have a characteristic curve as illustrated in <FIG>. Particularly, the blue filter <NUM> has a transmittance of about <NUM>% at approximately <NUM>, a transmittance of about <NUM>% at approximately <NUM>, a transmittance of about <NUM>% at approximately <NUM>, and a transmittance of about <NUM>% at approximately <NUM>. In particular, the characteristic curve of the blue filter <NUM> crosses the spectral curve of the blue light emitting diodes <NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM>,. , and <NUM>-n at the wavelength of approximately <NUM>.

As a result, the light passing through the blue filter <NUM> may have the maximum intensity at approximately <NUM>, as illustrated in <FIG>. Further, the wavelength deviation having the maximum intensity of the light passing through the blue filter <NUM> may be reduced to approximately <NUM>.

As described above, each of the plurality of blue light emitting diodes <NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM>,. , and <NUM>-n may emit light having the maximum intensity at the wavelength (approximately <NUM> to <NUM>) shorter than the blue wavelength. In addition, the blue filter <NUM> may block light having the wavelength shorter than the blue wavelength (approximately <NUM>) and pass light having the wavelength longer than the blue wavelength (approximately <NUM>), and the transmittance may be rapidly increased at the blue wavelength (approximately <NUM>).

As a result, the wavelength deviation of the light passing through the blue filter <NUM> may be significantly reduced compared to the wavelength deviation of the light emitted from the plurality of blue light emitting diodes <NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM>,. , and <NUM>-n. In other words, the wavelength deviation of the light emitted from the plurality of blue light emitting elements <NUM> may be significantly reduced compared to the wavelength deviation of the light emitted from the plurality of blue light emitting diodes <NUM>-<NUM>, <NUM>-<NUM>, <NUM>-<NUM>,. , and <NUM>-n.

In addition, a luminance correction process may be performed to reduce luminance deviation of light emitted from the plurality of blue light emitting elements <NUM>.

For example, the driving current may be supplied to the blue light emitting element <NUM>, and the luminance of the blue light emitting element <NUM> may be measured using a separately provided luminance meter (not shown). The driving current supplied to the blue light emitting element <NUM> may be controlled so that the luminance of the blue light emitting element <NUM> measured by the luminance meter has a predetermined luminance value.

As illustrated in <FIG>, each of the plurality of pixels P may further include a compensation circuit to compensate the driving current supplied to the blue light emitting element <NUM> together with the driving circuit that supplies the driving current to the blue light emitting element <NUM>.

By the compensation circuit provided in the plurality of pixels P, the plurality of blue light emitting elements <NUM> may emit light having a predetermined luminance value as illustrated in <FIG>. As a result, the luminance deviation of the light emitted from the plurality of blue light emitting elements <NUM> may be reduced.

As described above, the blue light emitting element may include the blue light emitting diode and the blue filter. The blue light emitting diode may emit light having the wavelength shorter than the blue wavelength, and the blue filter may block light having the wavelength shorter than the blue wavelength. As a result, the wavelength deviation of the blue light emitted from the plurality of blue light emitting elements may be reduced compared to the wavelength deviation of the light emitted from the blue light emitting diode.

The red light emitting element may include the blue light emitting diode and the red light conversion layer. The red light conversion layer may absorb light emitted from the blue light emitting diode and emit light having the red wavelength. The wavelength deviation of the red light emitted from the red light conversion layer may be reduced compared to the wavelength deviation of the light emitted from the blue light emitting diode.

In addition, the green light emitting element may include the blue light emitting diode and the green light conversion layer. The green light conversion layer may absorb light emitted from the blue light emitting diode and emit light having the green wavelength. The wavelength deviation of the green light emitted from the green light conversion layer may be reduced compared to the wavelength deviation of the light emitted from the blue light emitting diode.

<FIG> is a view illustrating a process of manufacturing a blue light emitting element included in the display apparatus illustrated in <FIG>. <FIG> is a view illustrating a process of manufacturing a red light emitting element included in the display apparatus illustrated in <FIG>. <FIG> is a view illustrating a process of manufacturing a green light emitting element included in the display apparatus illustrated in <FIG>.

The blue light emitting element <NUM> may include the blue light emitting diode, the transparent resin layer, and the blue filter.

As illustrated in <FIG>, the wafer W may be provided, and the plurality of light emitting diodes may be formed on the wafer W. For example, a plurality of the PN junctions may be formed by growing the first epitaxial layer containing the first impurity on the wafer W forming the substrate and then growing the second epitaxial layer containing the second impurity. Each of the plurality of PN junctions may be the light emitting diode.

Thereafter, as illustrated in <FIG>, the transparent resin layer <NUM> may be formed on the wafer W on which the plurality of light emitting diodes are formed. For example, the transparent resin layer <NUM> may be formed by applying (or coating) a liquid transparent resin onto the wafer W and curing the liquid transparent resin. The transparent resin layer <NUM> may be formed of various transparent resins such as PC, PES, PMMA, PVA, and PI.

Thereafter, as illustrated in <FIG>, the blue filter <NUM> may be formed on the wafer W on which the transparent resin layer <NUM> is formed. For example, the blue filter <NUM> may be formed by applying (or coating) a liquid blue pigment on the transparent resin layer <NUM> and curing the liquid blue pigment.

Thereafter, the blue light emitting element <NUM> may be manufactured by cutting the wafer W on which the transparent resin layer <NUM> and the blue filter <NUM> are formed to an appropriate size.

The red light emitting element <NUM> may include the blue light emitting diode, the red light conversion layer, and the red filter.

As illustrated in <FIG>, the wafer W may be provided, and the plurality of light emitting diodes may be formed on the wafer W. The wafer W on which the plurality of light emitting diodes are formed may be the same as the wafer W illustrated in <FIG>.

Subsequently, as illustrated in <FIG>, the red light conversion layer <NUM> may be formed on the wafer W on which the plurality of blue light emitting diodes are formed. For example, the red light conversion layer <NUM> may be formed by applying (or coat) a material on which the quantum dots having the diameter of approximately <NUM> and the liquid transparent resin are mixed on the wafer W and curing the material on which the quantum dots and the transparent resin are mixed.

Thereafter, the red filter <NUM> may be formed on the wafer W on which the red light conversion layer <NUM> is formed, as illustrated in <FIG>. For example, the red filter <NUM> may be formed by applying (or coating) a liquid red pigment on the red light conversion layer <NUM> and curing the liquid red pigment.

The green light emitting element <NUM> may include the blue light emitting diode, the green light conversion layer, and the green filter.

Subsequently, as illustrated in <FIG>, the green light conversion layer <NUM> may be formed on the wafer W on which the plurality of blue light emitting diodes are formed. For example, the green light conversion layer <NUM> may be formed by applying (or coat) a material on which the quantum dots having the diameter of approximately <NUM> and the liquid transparent resin are mixed on the wafer W and curing the material on which the quantum dots and the transparent resin are mixed.

Thereafter, the green filter <NUM> may be formed on the wafer W on which the green light conversion layer <NUM> is formed, as illustrated in <FIG>. For example, the green filter <NUM> may be formed by applying (or coating) a liquid green pigment on the green light conversion layer <NUM> and curing the liquid green pigment.

<FIG> is a view illustrating another example of light emitting elements included in a display apparatus according to an embodiment. <FIG> is a view illustrating a structure of a red light emitting element included in the display apparatus illustrated in <FIG> and a spectrum of light output from the red light emitting element. <FIG> is a view illustrating a structure of a green light emitting element included in the display apparatus illustrated in <FIG> and a spectrum of light output from the green light emitting element. <FIG> is a view illustrating a structure of a blue light emitting element included in the display apparatus illustrated in <FIG> and a spectrum of light output from the blue light emitting element.

As illustrated in <FIG>, the pixel P may include the red light emitting element <NUM>, the green light emitting element <NUM>, and the blue light emitting element <NUM>.

As illustrated in <FIG> and <FIG>, the red light emitting element <NUM> may include the first light emitting diode <NUM>, a first yellow light conversion layer <NUM>, and the red filter <NUM>.

The first light emitting diode <NUM> may receive the driving current from the driving circuit through the cathode terminal <NUM> and the anode terminal <NUM>. For example, as illustrated in <FIG>, at the wavelength λB1 shorter than the blue wavelength, the light having the maximum intensity (hereinafter referred to as 'light having the wavelength shorter than the blue wavelength) may be emitted.

The first yellow light conversion layer <NUM> may absorb light having the wavelength λB1 shorter than the blue wavelength emitted from the second light emitting diode <NUM>, and may emit light having the maximum intensity at the red wavelength λR (light having the red wavelength) and light having the maximum intensity at the green wavelength λG (light having the green wavelength). In other words, the first yellow light conversion layer <NUM> may convert light having the wavelength λB1 shorter than the blue wavelength to light having the red wavelength λR and light having the green wavelength λG.

For example, the first yellow light conversion layer <NUM> may include the quantum dots capable of emitting the red light and the quantum dots capable of emitting the green light.

In addition, the first yellow light conversion layer <NUM> may include a fluorescent material capable of emitting the red light and a fluorescent material capable of emitting the green light.

As illustrated in <FIG>, the light emitted from the first yellow light conversion layer <NUM> may include the light having the wavelength λB1 shorter than the blue wavelength that has passed through the first yellow light conversion layer <NUM>, and the light having the red wavelength λR whose wavelength is converted by the first yellow light conversion layer <NUM> and light having the green wavelength λG.

As illustrated in <FIG>, the red filter <NUM> may pass light having the red wavelength λR among the incident light and block light having a wavelength different from the red wavelength λR. Particularly, the red filter <NUM> may pass light having the red wavelength λR and block light having the wavelength λB1 shorter than the blue wavelength and light having the green wavelength λG.

As a result, as illustrated in <FIG>, the red light emitting element <NUM> may emit light having the maximum intensity at the red wavelength λR. In addition, the wavelength deviation of the light emitted from the first light emitting diode <NUM> may be reduced by the first yellow light conversion layer <NUM>.

As illustrated in <FIG> and <FIG>, the green light emitting element <NUM> may include the second light emitting diode <NUM>, a second yellow light conversion layer <NUM>, and the green filter <NUM>.

The second light emitting diode <NUM> and the second yellow light conversion layer <NUM> may be the same as the first light emitting diode <NUM> and the first yellow light conversion layer <NUM> illustrated in <FIG>. Particularly, the second light emitting diode <NUM> may emit light having the wavelength λB1 shorter than the blue wavelength, as illustrated in <FIG>. In addition, the second yellow light conversion layer <NUM> may convert the wavelength λB1 shorter than the blue wavelength to light having the red wavelength λR and light having the green wavelength λG. As illustrated in <FIG>, the second yellow light conversion layer <NUM> may emit light having the wavelength λB1 shorter than the blue wavelength, light having the red wavelength λR, and light having the green wavelength λG.

As illustrated in <FIG>, the green filter <NUM> may pass light having the green wavelength λBamong the incident light and may block light having the wavelength different from the green light. Particularly, the green filter <NUM> may pass light having the green wavelength λG, and may block light having the wavelength λB1 shorter than the blue wavelength and light having the red wavelength λR.

As a result, as illustrated in <FIG>, the green light emitting element <NUM> may emit light having the maximum intensity at the green wavelength λG. In addition, the wavelength deviation emitted from the second light emitting diode <NUM> may be reduced by the second yellow light conversion layer <NUM>.

As illustrated in <FIG> and <FIG>, the blue light emitting element <NUM> may include the third light emitting diode <NUM>, a third yellow light conversion layer <NUM>, and the blue filter <NUM>.

The third light emitting diode <NUM> and the third yellow light conversion layer <NUM> may be the same as the first light emitting diode <NUM> and the first yellow light conversion layer <NUM> illustrated in <FIG>. Particularly, the third light emitting diode <NUM> may emit light having the wavelength λB1 shorter than the blue wavelength, as illustrated in <FIG>. In addition, the third yellow light conversion layer <NUM> may convert the wavelength λB1 shorter than the blue wavelength to light having the red wavelength λR and light having the green wavelength λG. As illustrated in <FIG>, the third yellow light conversion layer <NUM> may emit light having the wavelength λB1 shorter than the blue wavelength, light having the red wavelength λR, and light having the green wavelength λG.

As illustrated in <FIG>, the blue filter <NUM> may pass light having the blue wavelength λB among the incident light and may block light having the wavelength different from the blue light. Particularly, the blue filter <NUM> may pass light having the blue wavelength λB, and may block light having the red wavelength λR and light having the green wavelength λG.

In addition, the third light emitting diode <NUM> may emit light having the wavelength λB1 shorter than the blue wavelength λB, and the blue filter <NUM> may block light having the wavelength shorter than the blue wavelength λB, and may pass light having the wavelength longer than the blue wavelength λB.

As a result, as illustrated in <FIG>, the blue light emitting element <NUM> may emit light having the maximum intensity at the blue wavelength λB. In addition, the wavelength deviation emitted from the third light emitting diode <NUM> may be reduced by the blue filter <NUM>.

<FIG> is a view illustrating a process of manufacturing a red light emitting element, a green light emitting element and a blue light emitting element illustrated in <FIG>.

As illustrated in <FIG>, the wafer W may be provided, and the plurality of blue light emitting diodes may be formed on the wafer W. For example, the plurality of PN junctions may be formed by growing the first epitaxial layer containing the first impurity on the wafer W forming the substrate and then growing the second epitaxial layer containing the second impurity. Each of the plurality of PN junctions may be the blue light emitting diode.

Thereafter, as illustrated in <FIG>, the yellow light conversion layers <NUM>, <NUM>, and <NUM> may be formed on the wafer W on which the plurality of blue light emitting diodes are formed. For example, the red light conversion layer <NUM> may apply (or coat) the material on which the quantum dots having the diameter of approximately <NUM>, the quantum dots having the diameter of approximately <NUM> and the liquid transparent resin are mixed on the wafer W, and may be formed by curing the material in which the quantum dots and the transparent resin are mixed.

Thereafter, as illustrated in <FIG>, the color filters <NUM>, <NUM>, and <NUM> may be formed on the wafer W on which the yellow light conversion layers <NUM>, <NUM>, and <NUM> are formed. The color filters <NUM>, <NUM>, and <NUM> may include the red filter <NUM>, the green filter <NUM>, and the blue filter <NUM>. The red filter <NUM>, the green filter <NUM>, and the blue filter <NUM> may be arranged side by side on the yellow light conversion layers <NUM>, <NUM>, and <NUM>. For example, the color filters <NUM>, <NUM>, and <NUM> may apply (or coat) the liquid red pigment, the green pigment, and the blue pigment on the yellow light conversion layers <NUM>, <NUM>, and <NUM>, and may be formed by curing the liquid pigments.

As illustrated in <FIG>, the display apparatus <NUM> may include the red light emitting element <NUM>, the green light emitting element <NUM>, and the blue light emitting element <NUM>.

As illustrated in <FIG> and <FIG>, the red light emitting element <NUM> may include a red light emitting diode <NUM> and the red filter <NUM>.

The red light emitting diode <NUM> may be supplied with the driving current from the driving circuit through a cathode terminal <NUM> and an anode terminal <NUM>. For example, as illustrated in <FIG>, the red light emitting diode <NUM> may emit light having the maximum intensity at a wavelength λR1 similar to the red wavelength λR and shorter than the red wavelength λR.

The red filter <NUM> may block light having the wavelength shorter than the red wavelength λR and pass light having the wavelength longer than the red wavelength λR. Of the light emitted from the red light emitting diode <NUM>, the light having the wavelength longer than the red wavelength λR may pass through the red filter <NUM>, and thus the light passing through the red filter <NUM> may have the maximum intensity at the red wavelength λR.

As a result, the red light emitting element <NUM> may emit light having the maximum intensity at the red wavelength λR, as illustrated in <FIG>. In addition, the wavelength deviation of the light emitted from the red light emitting diode <NUM> may be reduced by the red filter <NUM>.

As illustrated in <FIG> and <FIG>, the green light emitting element <NUM> may include a green light emitting diode <NUM> and the green filter <NUM>.

The green light emitting diode <NUM> may be supplied with the driving current from the driving circuit through a cathode terminal <NUM> and an anode terminal <NUM>. For example, as illustrated in <FIG>, the green light emitting diode <NUM> may emit light having the maximum intensity at the wavelength λG1 similar to the green wavelength λG and shorter than the green wavelength λG.

The green filter <NUM> may block light having the wavelength shorter than the green wavelength λG and pass light having the wavelength longer than the green wavelength λG. Of the light emitted from the green light emitting diode <NUM>, the light having the wavelength longer than the green wavelength λG may pass through the green filter <NUM>, and thus the light passing through the green filter <NUM> may have the maximum intensity at the green wavelength λG.

As a result, the green light emitting element <NUM> may emit light having the maximum intensity at the green wavelength λG, as illustrated in <FIG>. In addition, the wavelength deviation of the light emitted from the green light emitting diode <NUM> may be reduced by the green filter <NUM>.

As illustrated in <FIG> and <FIG>, the blue light emitting element <NUM> may include a blue light emitting diode <NUM> and the blue filter <NUM>.

The blue light emitting diode <NUM> may be supplied with the driving current from the driving circuit through a cathode terminal <NUM> and an anode terminal <NUM>. For example, as illustrated in <FIG>, the blue light emitting diode <NUM> may emit light having the maximum intensity at the wavelength λB1 similar to the blue wavelength λB and shorter than the blue wavelength λB.

The blue filter <NUM> may block light having the wavelength shorter than the blue wavelength λB and pass light having the wavelength longer than the blue wavelength λB. Of the light emitted from the blue light emitting diode <NUM>, the light having the wavelength longer than the blue wavelength λB may pass through the blue filter <NUM>, and thus the light passing through the blue filter <NUM> may have the maximum intensity at the blue wavelength λB.

As a result, the blue light emitting element <NUM> may emit light having the maximum intensity at the blue wavelength λB, as illustrated in <FIG>. In addition, the wavelength deviation of the light emitted from the blue light emitting diode <NUM> may be reduced by the blue filter <NUM>.

Meanwhile, the disclosed embodiments may be implemented in the form of a recording medium storing instructions that are executable by a computer. The instructions may be stored in the form of a program code, and when executed by a processor, the instructions may generate a program module to perform operations of the disclosed embodiments. The recording medium may be implemented as a computer-readable recording medium.

The computer-readable recording medium may include all kinds of recording media storing commands that can be interpreted by a computer. For example, the computer-readable recording medium may be ROM, RAM, a magnetic tape, a magnetic disc, flash memory, an optical data storage device, etc..

Claim 1:
A display apparatus (<NUM>) comprising:
a blue light emitting element (<NUM>) configured to emit blue light having a wavelength of <NUM> to <NUM>;
a red light emitting element (<NUM>) configured to emit red light having a wavelength of <NUM> to <NUM>, and
a green light emitting element (<NUM>) configured to emit green light having a wavelength of <NUM> to <NUM>,
wherein the blue light emitting element (<NUM>) comprises:
a first light emitting diode (<NUM>) configured to emit first light having a maximum intensity at a wavelength shorter than a blue wavelength;
a blue filter (<NUM>) configured to transmit light having the blue wavelength,
characterized in that the first light emitting diode (<NUM>) is configured to emit light having the maximum intensity at any one of <NUM> to <NUM>, and
wherein a blocking characteristic curve of the blue filter (<NUM>) is configured to cross a spectral curve of the first light emitting diode (<NUM>) at <NUM>.