Display substrate, manufacturing method thereof, and display device

Abstract

The present disclosure provides a display substrate and a preparation method thereof, and a display device, belonging to the field of display technology. The display substrate includes a base substrate, a plurality of pixel units arranged on the base substrate, and a color filter layer arranged on the light-emitting side of the pixel units; the pixel units include a plurality of light-emitting devices arranged on the base substrate; the light-emitting devices include a first electrode, a light-emitting layer, and a second electrode arranged in sequence on the base substrate; the color filter layer includes color filters of multiple colors, and is arranged in a one-to-one correspondence with the light-emitting devices; wherein one of the first electrode and the second electrode is a transmissive electrode and the other is a reflective electrode; the color filter is arranged on the side of the transmissive electrode away from the light-emitting layer; and for any pixel unit, at least part of the transmissive electrode has a different thickness.

Description

Technical Field

[0001] The present disclosure belongs to the field of display technology, and particularly relates to a display substrate and a preparation method thereof, and a display device. Background Art

[0002] In recent years, with the advancement of display technology, people have higher and higher requirements for the various performance of display devices. For example, organic light-emitting diodes (OLEDs) are widely used in the display field due to their light weight, self-luminescence, and fast response speed.

[0003] A light-emitting device generally includes an anode, a cathode, and a light-emitting layer. The principle of light emission is to provide appropriate voltage to the anode and cathode, so that the anode generates holes and the cathode generates electrons. The holes and electrons migrate to the light-emitting layer and recombine to emit light in the light-emitting layer, thereby realizing the light-emitting characteristics of the OLED device itself. The white light emitted by the light-emitting layer is displayed in color through the red, green, and blue (RGB) color film layers. However, in general, the light-emitting layer in the light-emitting device is evaporated using an open mask plate OPEN MASK, and the thickness of the transmission electrode on the light-emitting side of the light-emitting device is consistent, so that the OLED optics of the light-emitting device are consistent. Each light-emitting device cannot meet the strongest light output intensity at the same time, which also means that the color gamut of the light-emitting device in traditional technology is low, resulting in poor color performance of the display screen. Summary of the Invention

[0004] The present disclosure aims to solve at least one of the technical problems existing in the prior art and provide a (exclusive beneficial effect) of (exclusive name).

[0005] In a first aspect, the technical solution adopted to solve the technical problem of the present disclosure is a display substrate, which includes a base substrate, a plurality of pixel units arranged on the base substrate, and a color filter layer arranged on the light-emitting side of the pixel units;

[0006] The pixel unit includes a plurality of light-emitting devices arranged on the substrate; the light-emitting devices include a first electrode, a light-emitting layer, and a second electrode sequentially arranged on the substrate; the color filter layer includes color filters of multiple colors, and is arranged one-to-one corresponding to the light-emitting devices; wherein,

[0007] One of the first electrode and the second electrode is a transmissive electrode, and the other is a reflective electrode; the color filter is arranged on a side of the transmissive electrode away from the light-emitting layer;

[0008] For any of the pixel units, at least some of the transmissive electrodes have different thicknesses.

[0009] In some embodiments, the pixel unit includes four light-emitting devices arranged at intervals; the color filter layer includes a red filter, a green filter, a blue filter, and a white filter;

[0010] The four light emitting devices are respectively arranged in one-to-one correspondence with the red filter, the green filter, the blue filter and the white filter.

[0011] In some embodiments, the thickness of the transmissive electrode corresponding to the red filter is the same as the thickness of the transmissive electrode corresponding to the blue filter; the thickness of the transmissive electrode corresponding to the green filter is the same as the thickness of the transmissive electrode corresponding to the white filter.

[0012] In some embodiments, the thickness of the transmissive electrode corresponding to the red filter is between 60 nm and 80 nm.

[0013] In some embodiments, the thickness of the transmissive electrode corresponding to the green filter is between 130 nm and 150 nm.

[0014] In some embodiments, the thickness of the transmissive electrode corresponding to the blue filter is between 60 nm and 80 nm.

[0015] In some embodiments, the thickness of the transmissive electrode corresponding to the white filter is between 130 nm and 150 nm.

[0016] In some embodiments, the reflective electrode is a cathode;

[0017] For any of the pixel units, the reflective electrodes of the plurality of light-emitting devices are an integrated structure.

[0018] In some embodiments, the transmissive electrode is a cathode;

[0019] For any of the pixel units, the transmissive electrodes of the plurality of light-emitting devices are an integrated structure.

[0020] In some embodiments, for any of the pixel units, the light-emitting layers in the plurality of light-emitting devices are an integrated structure.

[0021] In a second aspect, the present disclosure also provides a method for preparing a display substrate, comprising:

[0022] providing a substrate;

[0023] A pixel unit is formed on the base substrate, and a color filter layer is formed on the light-emitting side of the pixel unit;

[0024] The pixel unit includes a plurality of light-emitting devices formed on the substrate; the light-emitting devices include a first electrode, a light-emitting layer, and a second electrode sequentially formed on the substrate; the color filter layer includes color filters of multiple colors, and is arranged one-to-one corresponding to the light-emitting devices; wherein,

[0025] One of the first electrode and the second electrode is a transmissive electrode, and the other is a reflective electrode; the color filter is formed on a side of the transmissive electrode away from the light-emitting layer;

[0026] For any of the pixel units, at least some of the transmissive electrodes have different thicknesses.

[0027] In a third aspect, an embodiment of the present disclosure further provides a display device, which includes a display substrate as described in any one of the above embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A schematic diagram of an exemplary display substrate provided in an embodiment of the present disclosure;

[0029] Figure 2 Schematic diagram of the spectrum of the transmissive electrode provided in the disclosed embodiment at two different thicknesses;

[0030] Figure 3 A schematic diagram of the CIE1976 chromaticity space provided in an embodiment of the present disclosure;

[0031] Figure 4 A schematic diagram of another exemplary display substrate provided in an embodiment of the present disclosure;

[0032] Figure 5a to Figure 5f Provided for the embodiments of the present disclosure Figure 1 The figure shows a schematic flow chart of a method for preparing a display substrate.

[0033] The figures are marked as follows: 10, substrate; 11, pixel unit; 20, transmission electrode; 30, light-emitting layer; 40, reflection electrode; 50, color filter layer; 51, white filter; 52, red filter; 53, green filter; 54, blue filter; 21, transmission electrode corresponding to the white filter; 22, transmission electrode corresponding to the red filter; 23, transmission electrode corresponding to the green filter; 24, transmission electrode corresponding to the blue filter; 201, first transmission electrode material. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solutions and advantages of the embodiments of the present disclosure clearer, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, not all of the embodiments. The components of the embodiments of the present disclosure generally described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present disclosure provided in the drawings is not intended to limit the scope of the disclosure for which protection is sought, but merely represents selected embodiments of the present disclosure. Based on the embodiments of the present disclosure, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present disclosure.

[0035] Unless otherwise defined, the technical or scientific terms used in this disclosure should have the usual meanings understood by people with ordinary skills in the field to which this disclosure belongs. The words "first", "second" and similar words used in this disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one", "an" or "the" do not indicate a quantity limitation, but rather indicate the existence of at least one. Words such as "include" or "comprise" mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0036] In this disclosure, "multiple or several" refers to two or more. "And / or" describes the relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can mean: A exists alone, A and B exist simultaneously, or B exists alone. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0037] In the related art, the light-emitting layer in a light-emitting device is typically deposited using an open mask throughout the entire layer, and the thickness of the transmissive electrode on the light-emitting side of the device is uniform. Because different cavity lengths enhance light at different wavelengths to varying degrees, the light output intensity of each light-emitting device is limited by the cavity length between the color filter layer and the light-emitting layer, i.e., the thickness of the transmissive electrode. This limited light output intensity of each light-emitting device means a lower color gamut for the light-emitting device, resulting in poor color performance on the displayed image.

[0038] Based on this, an embodiment of the present disclosure provides a display substrate, which includes a base substrate, a plurality of pixel units arranged on the base substrate, and a color filter layer arranged on the light-emitting side of the pixel unit; the pixel unit includes a plurality of light-emitting devices arranged on the base substrate; the light-emitting device includes a first electrode, a light-emitting layer, and a second electrode arranged in sequence on the base substrate; the color filter layer includes color filters of multiple colors, and is arranged in a one-to-one correspondence with the light-emitting devices; wherein, one of the first electrode and the second electrode is a transmissive electrode, and the other is a reflective electrode; the color filter is arranged on the side of the transmissive electrode away from the light-emitting layer; for any pixel unit, the thickness of at least part of the transmissive electrode is different.

[0039] The embodiments of the present disclosure specifically set the thickness of the transmissive electrodes in the light-emitting devices corresponding to the color filters of different colors based on the optical property that different cavity lengths have different enhancement effects on light at different wavelengths. By using transmissive electrodes of different thicknesses, the light output intensity of light of different colors is enhanced respectively, so that each light-emitting device can simultaneously meet the highest light output intensity, thereby improving the color gamut of the light-emitting device, thereby improving the breadth and richness of the colors of the displayed image, making the displayed image more vivid and full.

[0040] The specific structure of the display substrate is described in detail below. Figure 1 A schematic diagram of an exemplary display substrate provided in an embodiment of the present disclosure is shown as follows: Figure 1 As shown, it includes a base substrate 10 , a plurality of pixel units 11 arranged on the base substrate 10 , and a color filter layer 50 arranged on the light-emitting side of the pixel unit 11 . Figure 1 Taking a bottom emission type display substrate as an example, light is emitted from the bottom side of the pixel unit 11 , that is, the color filter layer 50 is disposed between the pixel unit 11 and the base substrate 10 .

[0041] Figure 1 Only one pixel unit 11 is shown. Similar to the structure of one pixel unit 11, multiple pixel units 11 can be arranged in an array on the substrate 10. Figure 1 As shown, the pixel unit 11 includes multiple light-emitting devices arranged on a base substrate 10. The light-emitting devices include a first electrode, a light-emitting layer 30, and a second electrode arranged in sequence on the base substrate. The color filter layer 50 includes color filters of multiple colors and is arranged one-to-one with the light-emitting devices.

[0042] For example, the first electrode may be an anode, and the second electrode may be a cathode. If the first electrode is a cathode, the second electrode may be an anode. For ease of understanding and description, the following embodiments of the present disclosure are described using the example of the first electrode being an anode and the second electrode being a cathode.

[0043] For example, the color filter layer 50 may include color filters corresponding to red, green, and blue, respectively, namely, a red filter 52, a green filter 53, and a blue filter 54. Alternatively, the color filter layer 50 may include color filters corresponding to red, green, blue, and white, respectively, namely, a red filter 52, a green filter 53, a blue filter 54, and a white filter 51. Alternatively, the color filter layer 50 may include a combination of any two or three of the color filters corresponding to red, green, blue, and white. Each color filter corresponds to a light-emitting device.

[0044] One of the first electrode and the second electrode is a transmissive electrode 20, and the other is a reflective electrode 40. Figure 1 As shown, the first electrode is a transmissive electrode 20 and the second electrode is a reflective electrode 40. The color filter is arranged on a side of the transmissive electrode 20 away from the light emitting layer 30.

[0045] For any pixel unit 11, at least some of the transmissive electrodes 20 have different thicknesses. For example, when the color filter layer 50 includes a red filter 52, a green filter 53, a blue filter 54, and a white filter 51, the thickness of the transmissive electrode 22 corresponding to the red filter 52 may be the same as the thickness of the transmissive electrode 24 corresponding to the blue filter 54, and different from the thickness of the transmissive electrode 23 corresponding to the green filter 53 and / or the thickness of the transmissive electrode 21 corresponding to the white filter 51. Alternatively, the thickness of the transmissive electrode 23 corresponding to the green filter 53 may be the same as the thickness of the transmissive electrode 21 corresponding to the white filter 51, and different from the thickness of the transmissive electrode 22 corresponding to the red filter 52 and / or the thickness of the transmissive electrode 24 corresponding to the blue filter 54.

[0046] In some embodiments, as Figure 1 As shown, the pixel unit 11 may include four light-emitting devices arranged at intervals. The color filter layer 50 may include a red filter 52, a green filter 53, a blue filter 54, and a white filter 51. The four light-emitting devices are arranged in a one-to-one correspondence with the red filter 52, the green filter 53, the blue filter 54, and the white filter 51, respectively.

[0047] In some embodiments, as Figure 1As shown, the thickness of the transmissive electrode 22 corresponding to the red filter 52 is the same as the thickness of the transmissive electrode 24 corresponding to the blue filter 54; the thickness of the transmissive electrode 23 corresponding to the green filter 53 is the same as the thickness of the transmissive electrode 21 corresponding to the white filter 51. With this arrangement, while each light-emitting device simultaneously meets the highest light output intensity, the transmissive electrode 22 corresponding to the red filter 52 and the transmissive electrode 24 corresponding to the blue filter 54, as well as the transmissive electrode 23 corresponding to the green filter 53 and the transmissive electrode 21 corresponding to the white filter 51, can be simultaneously prepared during the display substrate preparation stage, thereby saving time in preparing the color filter layer 50 and improving the preparation efficiency of the color filter layer 50.

[0048] Because different transmissive electrode 20 thicknesses have different light output preferences, affecting light output intensity, thinner optical thicknesses result in higher red and blue light output intensities, while thicker optical thicknesses result in higher green light output intensity and a more positive white light color point. To address this, the disclosed embodiments differentiate the thicknesses of the transmissive electrodes 20. The thickness of the transmissive electrode 22 corresponding to the red filter 52 and the thickness of the transmissive electrode 24 corresponding to the blue filter 54 are both smaller than the thickness of the transmissive electrode 23 corresponding to the green filter 53 and the thickness of the transmissive electrode 21 corresponding to the white filter 51, thereby improving the color gamut of different light-emitting devices. Figure 2 Schematic diagram of the spectrum of the transmission electrode at two different thicknesses provided in the disclosed embodiment, such as Figure 2 As shown, the thickness of one transmissive electrode is 70 nm, and the thickness of another transmissive electrode is 140 nm, wherein the abscissa represents the wavelength of visible light (unit: nanometer nm), and the ordinate represents the intensity (arbitrary unit, abbreviated as au).

[0049] In some embodiments, the thickness of the transmissive electrode 22 corresponding to the red filter 52 is between 60 nm and 80 nm. According to the thickness range of the transmissive electrode 22 corresponding to the red filter 52 and in combination with the actual application scenario, the thickness of the transmissive electrode 22 corresponding to the red filter 52 can be selectively set. Figure 2 As shown, the red light wavelength range is between 625nm and 740nm. Within this red light wavelength range, a transmissive electrode with a thickness of 70nm has a higher intensity than a transmissive electrode with a thickness of 140nm. Therefore, the thickness of the transmissive electrode 22 corresponding to the red filter 52 can be set to 70nm. Here, setting the thickness of the transmissive electrode 22 corresponding to the red filter 52 to 70nm can increase the light output intensity of the light-emitting device corresponding to the red filter 52, thereby increasing the intensity of the red light passing through the red filter 52, so that the red sub-pixel meets the maximum light output intensity, and improving the color gamut.

[0050] In some embodiments, the thickness of the transmissive electrode 24 corresponding to the blue filter 54 is between 60 nm and 80 nm. According to the thickness range of the transmissive electrode 24 corresponding to the blue filter 54 and in combination with the actual application scenario, the thickness of the transmissive electrode 24 corresponding to the blue filter 54 can be selectively set. Figure 2 As shown, the blue light wavelength range is between 400nm and 480nm. Within this blue light wavelength range, a transmissive electrode with a thickness of 70nm has a higher intensity than a transmissive electrode with a thickness of 140nm. Therefore, the thickness of the transmissive electrode 24 corresponding to the blue filter 54 can be set to 70nm. Here, setting the thickness of the transmissive electrode 24 corresponding to the blue filter 54 to 70nm can increase the light output intensity of the light-emitting device corresponding to the blue filter 54, thereby increasing the intensity of the blue light passing through the blue filter 54, so that the blue sub-pixel meets the maximum light output intensity, thereby improving the color gamut.

[0051] In some embodiments, the thickness of the transmissive electrode 23 corresponding to the green filter 53 is between 130 nm and 150 nm. According to the thickness range of the transmissive electrode 23 corresponding to the green filter 53 and in combination with the actual application scenario, the thickness of the transmissive electrode 23 corresponding to the green filter 53 can be selectively set. Figure 2 As shown, the green light wavelength range is between 577nm and 492nm. Within this green light wavelength range, the intensity of the transmissive electrode with a thickness of 140nm is higher than that of the transmissive electrode with a thickness of 700nm. Therefore, the thickness of the transmissive electrode 23 corresponding to the green filter 53 can be set to 140nm. Here, setting the thickness of the transmissive electrode corresponding to the green filter 53 to 140nm can increase the light output intensity of the light-emitting device corresponding to the green filter 53, thereby increasing the green light intensity passing through the green filter 53, so that the green sub-pixel meets the maximum light output intensity, and improving the color gamut.

[0052] Figure 3 A schematic diagram of the CIE1976 color space provided by an embodiment of the present disclosure. A represents the actual color gamut range when the thickness of the transmissive electrode 22 corresponding to the red filter 52, the thickness of the transmissive electrode 24 corresponding to the blue filter 54, and the thickness of the transmissive electrode 23 corresponding to the green filter 53 are set to 70 nm, and 140 nm, respectively. B represents the standard color gamut range. A clear comparison shows that the different transmissive electrode thicknesses set in the present disclosure achieve the highest light output intensity for each light-emitting device, enhancing the blue and green color gamut to over 99%, improving the breadth and richness of the displayed colors, and making the displayed image more vivid and full.

[0053] In some embodiments, the thickness of the transmissive electrode 21 corresponding to the white filter 51 is between 130 nm and 150 nm. According to the thickness range of the transmissive electrode 21 corresponding to the white filter 51 and in combination with the actual application scenario, the thickness of the transmissive electrode 21 corresponding to the white filter 51 can be selectively set. Optionally, the thickness of the transmissive electrode 21 corresponding to the white filter 51 is set to 140 nm. Figure 3 As shown, for example, the CIE_x of the standard white color point on the TV is between 0.28 and 0.29. Setting the thickness of the transmissive electrode 21 corresponding to the white filter 51 to be within 130nm to 150nm can make the color point of the white light emitted by the light-emitting device corresponding to the white filter 51 closer to the standard white color point, that is, the white color coordinate value is approximate. It should be noted that the closer the color point of the white light is to the standard white color point, the fewer complementary colors will be required for the subsequent light-emitting device, and the fewer complementary colors, the lower the power consumption. Therefore, the thickness of the transmissive electrode 21 corresponding to the white filter 51 is set to 140nm, so that the color point of the white light emitted by the light-emitting device corresponding to the white filter 51 is more correct, and no subsequent complementary colors are required, so that the power consumption of the light-emitting device is minimized.

[0054] In some embodiments, as Figure 1 As shown, the reflective electrode 40 is a cathode; for any pixel unit 11, the reflective electrodes 40 of the multiple light-emitting devices are an integrated structure.

[0055] In some embodiments, Figure 4 A schematic diagram of another exemplary display substrate provided in an embodiment of the present disclosure is shown in FIG. Figure 4 As shown, it includes a base substrate 10 , a plurality of pixel units 11 arranged on the base substrate 10 , and a color filter layer 50 arranged on the light-emitting side of the pixel unit 11 . Figure 4 Taking a top-emitting display substrate as an example, light is emitted from the top side of the pixel unit 11 , that is, the color filter layer 50 is disposed on the side of the pixel unit 11 facing away from the base substrate 10 . Figure 4 Only one pixel unit 11 is shown. Figure 4 As shown, the reflective electrode 40 serves as the anode, and the transmissive electrode 20 serves as the cathode. For any pixel unit 11, the transmissive electrodes 20 of multiple light-emitting devices form an integrated structure. The technical principles for improving the color gamut of the light-emitting devices and reducing power consumption are similar to those of the bottom-emission display substrate described above, and the repetitive details are not repeated here.

[0056] In some embodiments, for any pixel unit 11 , the light-emitting layers 30 in the plurality of light-emitting devices are an integrated structure.

[0057] In some embodiments, the thickness of the light emitting layer 30 is between 380 nm and 400 nm.

[0058] In some embodiments, the total thickness of the light-emitting layer 30 and the transmissive electrode 22 in the light-emitting device corresponding to the red filter 52 is between 450 nm and 470 nm. Optionally, the total thickness of the light-emitting layer 30 and the transmissive electrode 22 in the light-emitting device corresponding to the red filter 52 is 460 nm.

[0059] In some embodiments, the total thickness of the light-emitting layer 30 and the transmissive electrode 23 in the light-emitting device corresponding to the green filter 53 is between 520 nm and 540 nm. Optionally, the total thickness of the light-emitting layer 30 and the transmissive electrode 23 in the light-emitting device corresponding to the green filter 53 is 530 nm.

[0060] In some embodiments, the total thickness of the light-emitting layer 30 and the transmissive electrode 24 in the light-emitting device corresponding to the blue filter 54 is between 450 nm and 470 nm. Optionally, the total thickness of the light-emitting layer 30 and the transmissive electrode 24 in the light-emitting device corresponding to the blue filter 54 is 460 nm.

[0061] In some embodiments, the total thickness of the light-emitting layer 30 and the transmissive electrode 21 in the light-emitting device corresponding to the white filter 51 is between 520 nm and 540 nm. Optionally, the total thickness of the light-emitting layer 30 and the transmissive electrode 21 in the light-emitting device corresponding to the white filter 51 is 530 nm.

[0062] The above is the complete description of the specific structure of the display substrate.

[0063] The embodiments of the present disclosure also provide a method for preparing a display substrate, which is specifically used to prepare a display substrate of any one of the above embodiments. Specifically, a base substrate 10 is provided; a pixel unit 11 is formed on the base substrate 10, and a color filter layer 50 is formed on the light-emitting side of the pixel unit 11; the pixel unit 11 includes a plurality of light-emitting devices formed on the base substrate 10; the light-emitting device includes a first electrode, a light-emitting layer 30, and a second electrode formed in sequence on the base substrate 10; the color filter layer 50 includes color filters of multiple colors, and is arranged in a one-to-one correspondence with the light-emitting devices; wherein one of the first electrode and the second electrode is a transmissive electrode 20, and the other is a reflective electrode 40; the color filter is formed on the side of the transmissive electrode 20 away from the light-emitting layer 30; for any pixel unit 11, the thickness of at least part of the transmissive electrode 20 is different.

[0064] Based on the optical property that different cavity lengths enhance light at different wavelengths, the disclosed embodiments differentiate the thicknesses of the transmissive electrodes 20 corresponding to the color filters of different colors formed on the base substrate 10. Transmissive electrodes 20 of varying thickness are used to enhance the output intensities of light of different colors, enabling each light-emitting device to simultaneously achieve the highest output intensity, thereby improving the color gamut of the light-emitting devices. This enhances the breadth and richness of the colors displayed on the resulting display substrate, resulting in a more vivid and full-bodied display.

[0065] Figure 5a to Figure 5f Provided for the embodiments of the present disclosure Figure 1 The schematic diagram of the process of preparing the substrate is shown in FIG. Figure 5a As shown, a color filter layer 50 is formed on the provided base substrate 10, and the color filter layer includes a red filter 52, a green filter 53, a blue filter 54 and a white filter 51. Figure 5b As shown, a first transmissive electrode material 201 is formed on the side of the color filter layer 50 away from the base substrate 10, and its thickness is, for example, 70 nm; Figure 5c As shown, a photoresist is deposited on the first transmissive electrode material 201, and the photoresist is subjected to a first photolithography to form a first photolithography pattern; etching is performed according to the first photolithography pattern to form a portion of the transmissive electrode corresponding to the green filter 53 and the white filter 51. Figure 5d As shown, a second transmissive electrode material is continuously deposited on the side of the etched transmissive electrode material facing away from the base substrate 10, with a thickness of, for example, 70 nm; a photoresist is deposited on the second transmissive electrode material, and the photoresist is subjected to a second photolithography to form a second photolithography pattern; etching is performed according to the second photolithography pattern to form the transmissive electrode 22 corresponding to the red filter 52, another portion of the transmissive electrode 23 corresponding to the green filter 53, the transmissive electrode 24 corresponding to the blue filter 54, and another portion of the transmissive electrode 21 corresponding to the white filter 51, thus obtaining the transmissive electrodes of each light-emitting device. Figure 5e As shown, the light emitting layer 30 is formed on the side of the transmissive electrode 20 away from the color filter layer 50, for example, by using OPEN MASK full layer evaporation. Figure 5f As shown, a reflective electrode 40 is formed on a side of the light emitting layer 30 away from the transmissive electrode 20 .

[0066] In some embodiments, Figure 4The display substrate shown in FIG5 is prepared using the same process. Specifically, a reflective electrode material is deposited on a provided base substrate. A photoresist is deposited on the reflective electrode material and then photolithographically patterned to form a third photolithographic pattern. Etching is then performed according to the photolithographic pattern to form reflective electrodes 40 (anodes) corresponding to each color filter. A light-emitting layer 30 is formed on the side of the reflective electrode 40 facing away from the base substrate 10, for example, by using an open mask evaporation method. A third transmissive electrode material having a thickness of, for example, 140 nm is formed on the side of the light-emitting layer 30 facing away from the reflective electrode 40. A photoresist is deposited on the third transmissive electrode material and photolithographically processed to form a fourth photolithographic pattern. Etching is performed according to the fourth photolithographic pattern. For example, the light-transmitting region of the fourth photolithographic pattern faces the material of the transmissive electrode 22 corresponding to the red filter 52 and the material of the transmissive electrode 24 corresponding to the blue filter 54, and both are thinned (from a thickness of 140 nm to 70 nm) to form the transmissive electrode 22 corresponding to the red filter 52 and the transmissive electrode 24 corresponding to the blue filter 54. Simultaneously, the non-light-transmitting region of the fourth photolithographic pattern faces the transmissive electrode material corresponding to the green filter 53 and the transmissive electrode material corresponding to the white filter, forming the transmissive electrode 23 corresponding to the green filter 53 and the transmissive electrode 21 corresponding to the white filter 51. A color filter layer 50 is formed on a side of the transmissive electrode 20 facing away from the light emitting layer 30 . The color filter layer 50 includes a red filter 52 , a green filter 53 , a blue filter 54 and a white filter 51 .

[0067] The present disclosure also provides a display device comprising the display substrate described in any of the above embodiments. The display device can be, for example, a mobile phone, tablet computer, television, monitor, laptop computer, digital photo frame, navigation system, or any other product with a display function. Other essential components of the display device are readily understood by those skilled in the art and are not detailed here, nor should they be construed as limitations of the present disclosure.

[0068] It is understood that the above embodiments are merely exemplary embodiments for illustrating the principles of the present disclosure, and the present disclosure is not limited thereto. Those skilled in the art may make various modifications and improvements without departing from the spirit and substance of the present disclosure, and such modifications and improvements are also considered to be within the scope of protection of the present disclosure.

Claims

1. A display substrate comprising a base substrate, a plurality of pixel units disposed on the base substrate, and a color filter layer disposed on a light-emitting side of the pixel units; The pixel unit includes a plurality of light-emitting devices arranged on the substrate; the light-emitting devices include an anode, a light-emitting layer and a cathode arranged in sequence on the substrate; the color filter layer includes color filters of multiple colors, and is arranged one-to-one corresponding to the light-emitting devices; wherein, The anode is a transmissive electrode, and the cathode is a reflective electrode; or, the anode is a reflective electrode, and the cathode is a transmissive electrode; the color filter is arranged on a side of the transmissive electrode away from the light-emitting layer; For any of the pixel units, at least some of the transmissive electrodes have different thicknesses; The pixel unit includes four light-emitting devices arranged at intervals; the color filter layer includes a red filter, a green filter, a blue filter and a white filter; the four light-emitting devices are arranged in a one-to-one correspondence with the red filter, the green filter, the blue filter and the white filter respectively; and the thickness of the transmission electrode corresponding to the red filter and the thickness of the transmission electrode corresponding to the blue filter are both smaller than the thickness of the transmission electrode corresponding to the green filter and the thickness of the transmission electrode corresponding to the white filter.

2. The display substrate according to claim 1, wherein The thickness of the transmissive electrode corresponding to the red filter is the same as the thickness of the transmissive electrode corresponding to the blue filter; the thickness of the transmissive electrode corresponding to the green filter is the same as the thickness of the transmissive electrode corresponding to the white filter.

3. The display substrate according to claim 1, wherein The thickness of the transmissive electrode corresponding to the red filter is between 60 nm and 80 nm.

4. The display substrate according to claim 1, wherein: The thickness of the transmissive electrode corresponding to the green filter is between 130 nm and 150 nm.

5. The display substrate according to claim 1, wherein The thickness of the transmissive electrode corresponding to the blue filter is between 60nm and 80nm. The display substrate according to claim 1 , wherein: The thickness of the transmissive electrode corresponding to the white filter is between 130 nm and 150 nm.

7. The display substrate according to any one of claims 1 to 6, wherein The reflective electrode is a cathode; For any of the pixel units, the reflective electrodes of the plurality of light-emitting devices are an integrated structure.

8. The display substrate according to any one of claims 1 to 6, wherein The transmissive electrode is a cathode; For any of the pixel units, the transmissive electrodes of the plurality of light-emitting devices are an integrated structure.

9. The display substrate according to any one of claims 1 to 6, wherein For any of the pixel units, the light-emitting layers in the plurality of light-emitting devices are an integrated structure.

10. A method for preparing a display substrate, wherein: include: providing a substrate; A pixel unit is formed on the base substrate, and a color filter layer is formed on the light-emitting side of the pixel unit; The pixel unit includes a plurality of light-emitting devices formed on the substrate; the light-emitting devices include an anode, a light-emitting layer, and a cathode sequentially formed on the substrate; the color filter layer includes color filters of multiple colors, and is arranged one-to-one corresponding to the light-emitting devices; wherein, The anode is a transmissive electrode and the cathode is a reflective electrode; or the anode is a reflective electrode and the cathode is a transmissive electrode; the color filter is formed on a side of the transmissive electrode away from the light-emitting layer; For any of the pixel units, at least some of the transmissive electrodes have different thicknesses; The pixel unit includes four light-emitting devices arranged at intervals; the color filter layer includes a red filter, a green filter, a blue filter and a white filter; the four light-emitting devices are arranged in a one-to-one correspondence with the red filter, the green filter, the blue filter and the white filter respectively; and the thickness of the transmission electrode corresponding to the red filter and the thickness of the transmission electrode corresponding to the blue filter are both smaller than the thickness of the transmission electrode corresponding to the green filter and the thickness of the transmission electrode corresponding to the white filter.

11. A display device comprising the display substrate according to any one of claims 1 to 9.

Images