KR101651521B1 - Organic electro-luminescence device for medical - Google Patents

Abstract

TECHNICAL FIELD The present invention relates to a medical display device, and more particularly to a medical organic electroluminescent device.

A feature of the present invention is that a mono type WOLED is used as a medical display device and a mono type WOLED for a medical display device is configured to further include a specific color by constituting a color filter in some unit pixels in addition to black and white gray images, It can be thinner and lighter than a medical display device composed of a liquid crystal display device, and has a high resolution.

Further, the visibility is improved, and a specific region can be selectively emphasized and expressed in a monochrome image.

Mono type, WOLED, medical display, liquid crystal display, color filter

Description

TECHNICAL FIELD [0001] The present invention relates to an organic electroluminescent device for medical use,

TECHNICAL FIELD The present invention relates to a medical display device, and more particularly to a medical organic electroluminescent device.

The liquid crystal display device is characterized in that it has a large contrast ratio, is suitable for moving picture display, and has low power consumption, and is used in various fields such as a notebook computer, a monitor, and a TV. Liquid crystal has an optical anisotropy in which the molecular structure is thin and long and has a direction in the arrangement and a polarizing property in which the molecular alignment direction is changed according to the size when it is placed in an electric field.

That is, a typical liquid crystal display device includes a liquid crystal panel in which a liquid crystal layer is interposed between first and second substrates having an array layer for liquid crystal driving and a color-filter layer for color implementation This is an essential component, which changes the alignment direction of the liquid crystal molecules with an internal electric field, thereby causing a difference in transmittance.

The transmittance difference of the liquid crystal panel is displayed in the form of a color image by reflecting the color combination of the color filter through light of a back light placed on the back surface thereof.

1 is a schematic diagram of a general liquid crystal display device.

As shown in the figure, the liquid crystal display device 10 is largely divided into a liquid crystal panel 11 and a driving circuit unit (not shown) for supplying various signals necessary for realizing the image.

In this case, the liquid crystal panel 11 is composed of a liquid crystal layer and first and second substrates bonded together with the liquid crystal layer interposed therebetween. An array element for liquid crystal driving is provided on an inner surface of a first substrate called an array substrate, This defines a sub-pixel SP for displaying red (R), green (G), and blue (B) in a matrix in which a plurality of gate lines GL and data lines DL are arranged in an intersecting manner do.

A thin film transistor T is provided at each of these intersections to be connected in one-to-one correspondence with the pixel electrodes formed in the sub-pixels SP.

The inner surface of the second substrate, called a color filter substrate, includes color filters of red (R), green (G), and blue (B) colors corresponding to the respective subpixels (SP) A black matrix for covering the non-display elements such as the gate line GL, the data line DL and the thin film transistor T is provided.

In this liquid crystal panel 10, three sub-pixels SP for displaying red (R), green (G) and blue (B) form one unit pixel P to represent various colors.

In recent years, such a liquid crystal display device 10 has been designed as a mono liquid crystal display device that implements not only a notebook computer, a monitor, and a TV but also a gray image, and is applied to medical equipment.

That is, a liquid crystal display device used for medical equipment such as x-ray, ultrasonic diagnostic device, and radioisotope illuminator requires only fixed color and high coarse black and white.

Here, the medical liquid crystal display device that implements only the gray image removes only the red, green, and blue color filters from the color filter substrate, thereby realizing black and white gray images.

However, since such a medical liquid crystal display device is driven by the same driving circuit as the general liquid crystal display device 10 including a color filter even though the red, green, and blue color filters are removed, the configuration is complicated and the manufacturing cost is high .

Particularly, the medical liquid crystal display device requires a higher resolution than the general liquid crystal display device 10, but like the general liquid crystal display device 10, the three sub pixels SP are driven by one unit pixel P, Is difficult to implement.

SUMMARY OF THE INVENTION It is a first object of the present invention to provide a medical display device capable of displaying monochrome images of a fixed size and a high stereoscopic size.

The second object is to simplify the structure and reduce the manufacturing cost.

According to an aspect of the present invention, there is provided a liquid crystal display comprising: a first substrate on which a plurality of unit pixels are defined and on which a driving thin film transistor is formed for each unit pixel; An organic light emitting diode formed on the driving thin film transistor and electrically connected to the driving thin film transistor, the organic light emitting diode including white organic light emitting layer formed between the first and second electrodes and the first and second electrodes; And a second substrate bonded to the first substrate in a spaced apart manner, wherein a color filter is formed on a unit pixel selected from the plurality of unit pixels.

At this time, the color filter is formed in a mono type, and the color filter is formed only in a part of the unit pixel.

The color filter is formed on only one side of the display area and the color filter is a selected one of color filters emitting red (R), green (G) and blue (B) , Green (G), and blue (B) colors.

Here, the organic light emitting diode has a gray scale, and a bank is formed along an edge of the first electrode.

As described above, the present invention uses a mono-type WOLED as a medical display device and enables a medical display device WOLED to further implement specific colors in addition to black and white gray images, It is possible to make a light-weight thinner than a device, and it has an effect of having a high resolution.

Further, the visibility is improved, and a specific region can be selectively emphasized and expressed in a monochrome image.

Hereinafter, embodiments according to the present invention will be described in detail with reference to the drawings.

2 is a circuit diagram of a mono type WOLED which is a medical display device according to an embodiment of the present invention.

As shown in the drawing, a mono type organic electroluminescent device 100 (hereinafter, referred to as OLED), which is a medical display device according to an embodiment of the present invention, includes a plurality of pixels P, The organic electroluminescent diode E is formed.

Each pixel P is a region emitting white light. One electrode of the organic light emitting diode E and a light emitting layer are independently formed. Each pixel P is connected to a switching thin film transistor STr, A driving thin film transistor DTr, and a storage capacitor StgC.

In more detail, a gate line GL is formed in a first direction, and a data line GL extending in a second direction intersecting the first direction and defining a pixel P in addition to the gate line GL And a power supply line PL for applying a power supply voltage is formed. The power supply line PL is spaced apart from the data line DL.

A switching thin film transistor STr connected to the two wirings is formed in each pixel P where the gate wiring GL and the data wiring DL cross each other. The switching thin film transistor STr is connected to the driving thin film transistor DTr And the storage capacitor StgC and the driving thin film transistor DTr is connected between the power supply line PL and the organic electroluminescent diode E.

That is, the first electrode, which is one terminal of the organic electroluminescent diode E, is connected to the drain electrode of the driving thin film transistor DTr, and the second electrode, which is the other terminal, is grounded. At this time, the power supply line PL transfers the power supply voltage to the organic light emitting diode E.

Accordingly, when a signal is applied through the gate line GL, the switching thin film transistor STr is turned on for each pixel P, and the signal of the data line DL is applied to the driving thin film transistor Is transmitted to the gate electrode of the organic light emitting diode DTr and the driving thin film transistor DTr is turned on so that white light is output through the organic light emitting diode E.

At this time, when the driving thin film transistor DTr is turned on, the level of a current flowing from the power supply line PL to the organic electroluminescent diode E is determined, A gray scale can be realized.

The storage capacitor StgC maintains the gate voltage of the driving thin film transistor DTr constant when the switching thin film transistor STr is turned off so that the switching thin film transistor STr is turned off The level of the current flowing through the organic electroluminescent diode E can be kept constant until the next frame.

As described above, the medical display device of the present invention is a W (white) OLED 100 that is a self-luminous element that emits white light, and does not require a backlight used in a liquid crystal display (10 of FIG. 1) It is possible to make a lightweight thin.

Accordingly, since the manufacturing process is simple, it is advantageous in that the production cost can be saved more than the conventional liquid crystal display device (10 in FIG. 1).

In addition, compared to the liquid crystal display device (10 in FIG. 1), it has excellent viewing angle and contrast ratio, is advantageous in terms of power consumption, can be driven by DC low voltage, has a high response speed, , And the operating temperature range is also broad.

Particularly, the mono type WOLED 100 of the present invention realizes high resolution compared to the liquid crystal display (10 of FIG. 1), because three sub pixels (SP in FIG. 1) The WOLED 100 of the mono type of the present invention is different from the conventional liquid crystal display device 10 of FIG. 1 in that one sub-pixel (SP in FIG. 1) of the liquid crystal display device is one unit pixel P ).

Therefore, the mono type WOLED 100 of the present invention has a high resolution three times as high as that of the liquid crystal display (10 of FIG. 1) in terms of the number of the unit pixels P.

Meanwhile, the mono type WOLED 100 as a medical display device of the present invention is characterized in that a specific color is further implemented in addition to black and white gray images even in the case of WOLED 100 emitting white light.

This is possible by allowing a specific unit pixel P1 of the unit pixel P that implements the white light of the mono type WOLED 100 to implement a specific color. That is, as shown in FIG. The pixel P1 emits blue light in addition to white light, and unit pixels P and P1 emitting white light and blue light are repeatedly arranged adjacent to each other.

 Thus, visibility is improved in spite of being a medical display device, and a specific area can be selectively emphasized and expressed in a monochrome image.

This will be described in more detail with reference to FIGS. 3A to 3B.

FIG. 3A is a cross-sectional view schematically showing a mono type WOLED which is a medical display device according to an embodiment of the present invention, and FIG. 3B is an enlarged cross-sectional view of part of FIG.

Meanwhile, the mono type WOLED 100, which is a medical display device according to the present invention, is divided into a top emission type and a bottom emission type according to the transmission direction of the emitted white light. The lower light emitting method will be described as an example.

For convenience of explanation, a region where the driving thin film transistor DTr is formed in each unit pixel P is referred to as a driving region DA and a region where the bank 221 is formed is referred to as a non-pixel region NA, Emitting region 113 is defined as a light-emitting region PA.

 A mono type WOLED 100 as a medical display device of the present invention includes a first substrate 101 on which a driving thin film transistor DTr and an organic light emitting diode E are formed, And the first and second base plates 101 and 102 are spaced apart from each other. The edge portions of the first and second base plates 101 and 102 are sealed and adhered via a seal pattern 120.

On the inner surface of the second substrate 102, a moisture absorbent 117 for removing water permeated from the outside is formed.

A semiconductor layer 201 is formed on the first substrate 101. The semiconductor layer 201 is made of silicon and has a central portion on both sides of the active region 201a and the active region 201a forming a channel. And doped source and drain regions 201b and 201c.

A gate insulating layer 203 is formed on the semiconductor layer 201.

A gate electrode 205 corresponding to the semiconductor layer 201a and a gate wiring extending in one direction although not shown in the figure are formed on the gate insulating film 203.

A first interlayer insulating film 207a and a gate insulating film 203 under the first interlayer insulating film 207a are formed on the entire upper surface of the gate electrode 205 and the gate wiring (not shown) And first and second semiconductor layer contact holes 209a and 209b that respectively expose the source and drain regions 201b and 201c on both sides.

Next, upper portions of the first interlayer insulating film 207a including the first and second semiconductor layer contact holes 209a and 209b are separated from each other by the source and the drain, which are exposed through the first and second semiconductor layer contact holes 209a and 209b, And source and drain electrodes 211 and 213 which are in contact with the drain regions 201b and 201c, respectively.

And a drain contact hole 215 exposing the drain electrode 213 over the first interlayer insulating film 207a exposed between the source and drain electrodes 211 and 213 and the two electrodes 211 and 213. [ An insulating film 207b is formed.

At this time, the semiconductor layer 201 including the source and drain electrodes 211 and 213 and the source and drain regions 201b and 201c in contact with the electrodes 211 and 213 and the gate insulating film 201 formed on the semiconductor layer 201 The gate electrode 203 and the gate electrode 205 constitute a driving thin film transistor DTr.

The driving thin film transistor DTr includes a polysilicon semiconductor layer and is shown as a top gate type. As a modification thereof, the driving thin film transistor DTr may be a bottom gate made of amorphous silicon (107a, 107b) Or a bottom gate type.

A second interlayer insulating film 207b having a drain contact hole 215 exposing the drain electrode 213 is formed on the source and drain electrodes 211 and 213. [

The first electrode 111, the organic light emitting layer 113 and the second electrode 115 constituting the organic electroluminescent diode E are sequentially formed on the second interlayer insulating film 207b, Respectively.

The first and second electrodes 111 and 115 and the organic light emitting layer 113 formed therebetween form an organic light emitting diode E.

The first electrode 111 is connected to the drain electrode 213 of the driving thin film transistor DTr.

In this case, when the mono type WOLED 100 is a bottom emission type, the first electrode 111 may be a transparent conductive material having a relatively large work function value, for example, indium (ITO) or indium-zinc-oxide (IZO).

The second electrode 115 may be made of a non-transparent conductive material to serve as a cathode electrode.

The second electrode 115 may be formed of a metal material having a relatively low work function value such as aluminum (Al), aluminum alloy (AlNd), silver (Ag), magnesium (Mg) (AlMg).

Accordingly, the white light emitted from the organic light emitting layer 113 is driven by the lower light emitting method in which the white light is emitted toward the first electrode 111.

Here, the organic light emitting layer 113 may be a single layer made of a light emitting material. In order to increase the light emitting efficiency, a hole injection layer, a hole transporting layer, an emitting material layer, And may be composed of multiple layers of an electron transporting layer and an electron injection layer.

The organic light emitting layer 113 of the present invention may include a plurality of organic light emitting materials that emit red (R), green (G), and blue (B) light to emit white light, And is formed as a pair of two organic light emitting materials.

A bank 221 is located between the first electrodes 111 formed for each unit pixel P.

That is, the banks 221 are formed in a matrix type of a lattice structure as a whole on the first substrate 101 so that the first electrodes 111 are connected to the unit pixels P by using the banks 221 as boundaries for the unit pixels P, Are formed in a separated structure.

When a predetermined voltage is applied to the first electrode 111 and the second electrode 115 in accordance with the selected color signal, the WOLED 100 of the mono type may apply a predetermined voltage to the first electrode 111 and the second electrode 115, 115 are transported to the organic light emitting layer 113 to form an exciton. When the excitons are transited from the excited state to the ground state, light is emitted to emit white light.

At this time, since the emitted white light passes through the transparent first electrode 111 and goes out to the outside, the WOLED 100 realizes an arbitrary image.

Although the driving thin film transistor DTr and the organic light emitting diode E are formed on the same substrate as the driving thin film transistor DTr and the organic light emitting diode E, May be formed on different substrates.

The mono-type WOLED 100 of the present invention, which is the medical display device of the present invention, implements white light and further realizes a specific color. This realizes a specific color except black and white in a specific unit pixel P1 By forming the color filter 123,

That is, the monolithic WOLED 100 of the present invention does not form the color filter 123 on all the unit pixels P, but forms a color filter 123 that realizes a specific color only on a specific unit pixel P1 .

That is, the color filter 123 is formed in a mono type in an area where an image is realized.

The color filter 123 is formed on the first interlayer insulating film 207a of the light emitting area PA on one side of the driving region DA so that the mono type WOLED 100, And a specific color is emitted according to the color of the color filter 123.

Accordingly, the mono type WOLED 100 of the present invention improves visibility in spite of being a medical display device, and can selectively express a specific region in a monochrome image.

FIG. 4 is an example of an x-ray image implemented through a mono type WOLED (100 in FIG. 3B) that is a medical display device according to an embodiment of the present invention. At this time, in the embodiment of the present invention, a color filter of blue color (123 of FIG. 3B) is further provided to realize a color of black, white and blue.

Here, the x-ray image is briefly described. The x-ray image transmits a body part to be photographed with a certain amount of X-ray, measures the amount of X-rays transmitted through the X-ray sensor, And the X-ray absorption rate of each point on the body part is determined by the computer, and the image is reconstructed into an image. At this time, the area where the absorption rate of the X-ray is high is expressed by white and the other area is represented by black.

That is, the photographed body part is realized as white, and the other area is realized in black, thereby expressing the photographed part of the body.

Accordingly, the medical display device of the present invention is a mono type WOLED having a resolution three times as high as that of the conventional liquid crystal display device as each sub-pixel is defined as one unit pixel (P in FIG. 3B) Can be expressed very precisely.

In particular, as shown in FIG. 4, the medical display device of the present invention further implements blue color in addition to black and white, and expresses a specific region or additional information in an x-ray image through a blue color.

As a result, visibility is improved in spite of being a medical display device, and a specific area can be selectively emphasized to blue in a monochrome image.

Here, the unit pixel for realizing the blue color is realized only in the specific unit pixel as described above, and FIGS. 5A to 5E are plan views schematically showing a state where the blue color filter is disposed for each unit pixel.

It is also possible to form the color filter 123 only in a part of the unit pixel P1 so that white light is realized in an area where the color filter 123 is not formed as shown in Fig.

5B and 5C, a unit pixel that implements white light and a unit pixel that implements blue light are sequentially arranged in a row direction in which the blue color is realized in the horizontal direction, so that the blue color is realized in the entire display area of the monolithic WOLED 100 Or may be formed in a vertical stripe arrangement or in a quad scheme in which rows and columns are arranged in the form of a matrix in the same area.

Alternatively, as shown in FIGS. 5D and 5E, the white light and the blue light may be implemented only in a part of the display area of the monolithic WOLED 100, or only blue light may be realized in some areas.

In this case, even when white light and blue light are both realized in a part of the display area, a unit pixel for realizing white light and a unit pixel for realizing blue light can be arranged in a stripe type or a quad type.

It is also possible for the mono type WOLED 100 of the present invention to form color filters of two specific colors as well as color filters of one specific color (123 of FIG. 5A).

In this case, the WOLED 100 can implement two specific colors in addition to the black and white gray images, or can implement a specific color by mixing two specific colors.

As described above, the present invention uses a mono-type WOLED 100 as a medical display device, thereby making it possible to make a lightweight and thinner device than a medical display device composed of a liquid crystal display device (10 of Fig. 1). In addition, since the manufacturing process is simple, the manufacturing cost can be further reduced as compared with the conventional liquid crystal display device (10 in FIG. 1).

In addition, compared to the liquid crystal display device (10 in FIG. 1), it has excellent viewing angle and contrast ratio, is advantageous in terms of power consumption, can be driven by DC low voltage, has a high response speed, , And the operating temperature range is also broad.

Further, the mono type WOLED 100 of the medical display device of the present invention has a resolution as high as three times that of the liquid crystal display device (10 of Fig. 1).

In particular, the WOLED 100, which is a medical display device of the present invention, can realize specific colors in addition to black and white gray images, thereby improving visibility and selectively emphasizing a specific area in a black and white image.

The present invention is not limited to the above-described embodiments, and various modifications may be made without departing from the spirit of the present invention.

1 is a schematic view of a general liquid crystal display device.

2 is a circuit diagram of a mono type WOLED which is a medical display device according to an embodiment of the present invention.

FIG. 3A is a cross-sectional view schematically showing a mono type WOLED as a medical display device according to an embodiment of the present invention; FIG.

FIG. 3B is an enlarged cross-sectional view of a part of FIG. 3A. FIG.

4 is an exemplary view of an x-ray image implemented through a mono type WOLED, which is a medical display device according to an embodiment of the present invention;

5A to 5E are plan views schematically showing a state in which a blue color filter is disposed for each unit pixel.

Claims (8)

A first substrate including a plurality of unit pixels and a driving thin film transistor arranged in each of the plurality of unit pixels, wherein one sub pixel is defined as one unit pixel; An organic light emitting diode disposed above the driving thin film transistor and electrically connected to the driving thin film transistor, the organic light emitting diode including white light, the organic light emitting layer being provided between the first and second electrodes and the first and second electrodes; And a second substrate spaced apart from and bonded to the first substrate, Wherein one or two color filters selected from among color filters emitting red (R), green (G), and blue (B) colors are disposed in a selected unit pixel among the plurality of unit pixels. The method according to claim 1, Wherein the color filters are arranged in a mono type. 3. The method of claim 2, Wherein the color filter is disposed only in a part of the unit pixel. 3. The method of claim 2, Wherein the color filter is disposed only on one side of the display region. delete delete The method according to claim 1, Wherein the organic electroluminescent diode realizes a gray scale. The method according to claim 1, And a bank is disposed along an edge of the first electrode.

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