A light emitting device

Abstract

The present invention discloses a light-emitting device, comprising: a substrate and at least one first light-emitting area arranged on the substrate; each first light-emitting area comprises a plurality of sub-light-emitting units, each sub-light-emitting unit is electrically connected to a first end of an anti-short-circuit resistor, and the second end of the anti-short-circuit resistor connected to the sub-light-emitting units of the same first light-emitting area is electrically connected to the same driving line, and the driving line is used to transmit a driving signal to the sub-light-emitting units; at least some of the sub-light-emitting units in the first light-emitting area have different light-emitting areas; the resistance value of the anti-short-circuit resistor of the sub-light-emitting unit is determined according to the light-emitting area of ​​each sub-light-emitting unit in the first light-emitting area, the current density parameter of the sub-light-emitting unit, and the ratio setting value of the maximum current density to the minimum current density of the sub-light-emitting units with different light-emitting areas in the first light-emitting area; wherein the current density parameter is a relationship parameter between the current density of the sub-light-emitting unit and the equivalent resistance. The present invention can improve the light-emitting uniformity of the light-emitting device.

Description

Technical Field

[0001] The present invention relates to the technical field of short circuit prevention, and in particular to a light emitting device. Background Art

[0002] Organic Light-Emitting Diode (OLED) screens inevitably have defects such as dust particles, burrs, pinholes, and cracks during the manufacturing process, and the distance between the anode and cathode of OLED is usually very small (about tens to hundreds of nanometers). In this state, the anode and cathode may directly contact each other to cause defects (called short-circuit points), or the organic layer between the anode and cathode may become thinner than other locations. When the OLED is working, the current tends to pass through this short-circuit point rather than other locations, causing heat to accumulate at the short-circuit point, thereby damaging the quality and reliability of the entire device.

[0003] Under the same conditions, the larger the light-emitting area of ​​the OLED screen, the greater the possibility of short-circuit points. It is possible to reduce short-circuit points by increasing the thickness of the organic layer, but this requires the OLED to use a higher driving voltage, which affects the device efficiency, and it cannot completely eliminate short-circuit points. The short-circuit point problem may be solved by adding a short-circuit protection part.

[0004] In the prior art, using structures or materials to make anti-short circuit parts can effectively increase the reliability of devices. The design of the anti-short circuit part mainly uses the materials or geometric structures used in the anti-short circuit part to achieve a certain impedance. By adjusting the resistance of the anti-short circuit part, the current loss of the short-circuited pixel is reduced, ensuring that the overall brightness is not too large. However, the existing screen body with anti-short circuit resistors has the problem of uneven luminous brightness. Summary of the invention

[0005] The present invention provides a light emitting device, which can improve the light emitting uniformity of the light emitting device while achieving the short circuit prevention effect.

[0006] According to one aspect of the present invention, there is provided a light emitting device, comprising:

[0007] A substrate and at least one first light emitting area disposed on the substrate;

[0008] Each of the first light-emitting areas includes a plurality of sub-light-emitting units, each of the sub-light-emitting units is electrically connected to a first end of an anti-short-circuit resistor, and a second end of the anti-short-circuit resistor connected to the sub-light-emitting units in the same first light-emitting area is electrically connected to the same driving line, and the driving line is used to transmit a driving signal to the sub-light-emitting units; at least some of the sub-light-emitting units in the first light-emitting area have different light-emitting areas;

[0009] The resistance value of the anti-short-circuit resistor of the sub-light-emitting unit is determined according to the light-emitting area of ​​each of the sub-light-emitting units in the first light-emitting zone, the current density parameter of the sub-light-emitting unit, and the ratio of the maximum current density to the minimum current density of the sub-light-emitting units with different light-emitting areas in the first light-emitting zone; wherein the current density parameter is a relationship parameter between the current density of the sub-light-emitting unit and the equivalent resistance.

[0010] Optionally, the plurality of sub-light-emitting units of the first light-emitting area include a plurality of first sub-light-emitting units and at least one second sub-light-emitting unit, wherein the light-emitting area of ​​the first sub-light-emitting unit is different from the light-emitting area of ​​the second sub-light-emitting unit, and the light-emitting areas of all the first sub-light-emitting units are the same; the light-emitting areas of each type of second sub-light-emitting unit are the same, and the light-emitting areas of different types of second sub-light-emitting units are different;

[0011] The resistance value of the anti-short-circuit resistor of the first sub-light-emitting unit is determined according to the equivalent resistance of the first sub-light-emitting unit when it is not short-circuited, the equivalent resistance of the first sub-light-emitting unit when it is short-circuited, and the number of sub-light-emitting units in the first light-emitting area;

[0012] The resistance value of the anti-short-circuit resistor of the second sub-light-emitting unit is determined according to the resistance value of the anti-short-circuit resistor of the first sub-light-emitting unit, the light-emitting area of ​​each of the sub-light-emitting units in the first light-emitting zone, the current density parameter of each sub-light-emitting unit in the first light-emitting zone, and the ratio setting value of the maximum current density to the minimum current density of the sub-light-emitting units with different light-emitting areas in the first light-emitting zone.

[0013] Optionally, within the set brightness range, the value of the equivalent resistance of each sub-light-emitting unit and the value of the current density of the sub-light-emitting unit satisfy the first relationship: R 等效 =a*J b , where R 等效 is the equivalent resistance, J is the current density, a and b are current density parameters, and at least one of a and b of the sub-light-emitting units with different light-emitting areas is different.

[0014] Optionally, the maximum current density and the minimum current density are determined according to the equivalent resistance of all sub-light-emitting units of each light-emitting area obtained through multiple iterations and the light-emitting area of ​​each sub-light-emitting unit;

[0015] In the first iteration, the first iteration equivalent resistance of all sub-light-emitting units of each light-emitting area is determined according to the initial preset current density, and the first iteration equivalent current density of all sub-light-emitting units of each light-emitting area is determined according to each of the first iteration equivalent resistances and the light-emitting area of ​​each sub-light-emitting unit;

[0016] In the second iteration, the second iteration equivalent resistance of all sub-light-emitting units of each light-emitting area is determined according to the first iteration equivalent current density, and the second iteration equivalent current density of all sub-light-emitting units of each light-emitting area is determined according to each of the second iteration equivalent resistances and the light-emitting area of ​​each sub-light-emitting unit;

[0017] The nth iteration equivalent resistance of all sub-light-emitting units of each light-emitting area is obtained by analogy.

[0018] Optionally, the resistance value of the short-circuit protection resistor of the first sub-light-emitting unit is determined according to the following formula:

[0019]

[0020] Among them, A is a fixed value less than or equal to the set value, R cell-org is the equivalent resistance of the first sub-light-emitting unit, R cell-spl is the resistance value of the short-circuit protection resistor of the first sub-light-emitting unit, R cell-s is the equivalent resistance of the first sub-light-emitting unit when it is short-circuited, and n is the number of sub-light-emitting units in the first light-emitting area.

[0021] Optionally, A is less than or equal to 10%.

[0022] Optionally, the ratio setting value is less than or equal to 1.05.

[0023] Optionally, the driving line is in a grid shape, the sub-light emitting units are arranged in the grid of the driving line, different sub-light emitting units are arranged in different grids, and each sub-light emitting unit is electrically connected to the driving line through a lead wire;

[0024] The lead wire is the anti-short circuit resistor.

[0025] Optionally, at least one of lead width, lead length and lead thickness of leads connecting sub-light-emitting units with different light-emitting areas is different.

[0026] Optionally, the sub-light-emitting unit comprises a first electrode, a light-emitting functional layer and a second electrode which are stacked in sequence, and the second electrode is arranged on a side of the light-emitting functional layer away from the substrate;

[0027] The second electrodes of all sub-light-emitting units in the same first light-emitting area are connected to each other, and the first electrodes of the sub-light-emitting units are electrically connected to the first end of the short-circuit prevention resistor.

[0028] The resistance value of the anti-short-circuit resistor of the sub-light-emitting unit in the embodiment of the present invention is determined according to the light-emitting area of ​​each sub-light-emitting unit in the first light-emitting zone, the current density parameter of the sub-light-emitting unit, and the set value of the ratio of the maximum current density to the minimum current density of the sub-light-emitting units with different light-emitting areas in the first light-emitting zone. After setting the anti-short-circuit resistor, the difference in current density between different sub-light-emitting units is small, and the difference in brightness between different sub-light-emitting units is small, thereby improving the light-emitting uniformity of the first light-emitting zone and improving the light-emitting uniformity of the light-emitting device.

[0029] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0031] Figure 1 is a schematic diagram of a light emitting device provided by an embodiment of the present invention;

[0032] Figure 2 yes Figure 1 A cross-sectional view of the light emitting device along section line AA. DETAILED DESCRIPTION

[0033] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0034] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0035] As mentioned in the background technology, the existing screen with anti-short-circuit resistors has the problem of uneven luminous brightness. The inventors have found through research that the reason for this problem is that the luminous area of ​​the pixels at the edge of the luminous area is smaller than the luminous area of ​​other pixels. The existing technology sets the resistance value of the anti-short-circuit resistors of all pixels to be the same, causing the brightness of the edge pixels to be higher than the normal pixels in the middle, resulting in uneven luminous brightness.

[0036] An embodiment of the present invention provides a light emitting device, Figure 1 is a schematic diagram of a light emitting device provided by an embodiment of the present invention, with reference to Figure 1 , the light emitting device comprises:

[0037] A substrate 10 and at least one first light emitting area 20 disposed on the substrate 10;

[0038] Each first light-emitting area 20 includes a plurality of sub-light-emitting units 21, each sub-light-emitting unit 21 is electrically connected to a first end of an anti-short-circuit resistor 30, and the second end of the anti-short-circuit resistor 30 connected to the sub-light-emitting units 21 of the same first light-emitting area 20 is electrically connected to the same driving line 40, and the driving line 40 is used to transmit a driving signal to the sub-light-emitting unit 21; at least some of the sub-light-emitting units 21 in the first light-emitting area 20 have different light-emitting areas;

[0039] The resistance value of the anti-short-circuit resistor 30 of the sub-light-emitting unit 21 is determined according to the light-emitting area of ​​each sub-light-emitting unit 21 in the first light-emitting zone 20, the current density parameter of the sub-light-emitting unit 21, and the ratio of the maximum current density to the minimum current density of the sub-light-emitting units 21 with different light-emitting areas in the first light-emitting zone 20; wherein the current density parameter is a relationship parameter between the current density of the sub-light-emitting unit 21 and the equivalent resistance.

[0040] Among them, the substrate 100 can be a flexible substrate or a rigid substrate. The material of the substrate 100 can be glass or polyimide, etc. The light-emitting device can include one, two or more first light-emitting areas 20. The multiple sub-light-emitting units 21 of each first light-emitting area 20 are simultaneously controlled to emit light through the same driving line 40. The sub-light-emitting unit 21 can be an organic light-emitting unit, and the sub-light-emitting unit 21 can include a first electrode, an organic light-emitting layer, and a second electrode stacked in sequence. The first electrodes of the multiple sub-light-emitting units 21 in the same first light-emitting area 20 are insulated from each other, the second electrodes are electrically connected to each other, and the first electrode of the sub-light-emitting unit 21 is electrically connected to the anti-short-circuit resistor 30. Or the first electrodes of the multiple sub-light-emitting units 21 in the same first light-emitting area 20 are electrically connected to each other, the second electrodes are insulated from each other, and the second electrode is electrically connected to the anti-short-circuit resistor 30.

[0041] Specifically, in each first light-emitting area 20, each sub-light-emitting unit 21 is connected in series with an anti-short-circuit resistor 30 to form a series unit, and different series units are connected in parallel. The relationship between the equivalent resistance and current density of the sub-light-emitting unit 21 of each light-emitting area can be determined in advance through simulation experiments. The relationship is expressed by a current density parameter, and the current density parameters of the sub-light-emitting units 21 of different light-emitting areas are different. Assuming that the current density of all sub-light-emitting units 21 is equal, the equivalent resistance of the sub-light-emitting unit 21 is calculated according to the relationship between the equivalent resistance and current density of each sub-light-emitting unit 21. Then, according to the current shunt formula of multiple parallel resistors, the current divided by each sub-light-emitting unit 21 and its series anti-short-circuit resistor 30 is calculated, thereby calculating the current density of each sub-light-emitting unit 21. The equivalent resistance of the sub-light-emitting unit 21 is calculated again according to the newly calculated current density, and the current density of the sub-light-emitting unit 21 is calculated again. After multiple iterative calculations, the current density of each sub-light-emitting unit 21 tends to be stable, and the current density of each sub-light-emitting unit 21 after stabilization is determined as the actual current density of the sub-light-emitting unit 21. The actual current density of the sub-light-emitting unit 21 is an expression including the light-emitting area, current density parameter and anti-short-circuit resistance of each sub-light-emitting unit 21. Since the current density reflects the brightness of the sub-light-emitting unit 21, the current density difference requirement can be determined according to the brightness difference requirement of each sub-light-emitting unit 21, that is, the ratio setting value of the maximum current density to the minimum current density of the sub-light-emitting unit 21 with different light-emitting areas is determined. The ratio of the actual current density of different sub-light-emitting units 21 is set to be less than or equal to the ratio setting value of the maximum current density to the minimum current density, and the anti-short-circuit resistance of each sub-light-emitting unit 21 is calculated.

[0042] The resistance value of the anti-short-circuit resistor of the sub-light-emitting unit in the embodiment of the present invention is determined according to the light-emitting area of ​​each sub-light-emitting unit 21 in the first light-emitting zone 20, the current density parameter of the sub-light-emitting unit 21, and the ratio setting value of the maximum current density to the minimum current density of the sub-light-emitting units 21 with different light-emitting areas in the first light-emitting zone 20. After the anti-short-circuit resistor 30 is set, the difference between the current density of different sub-light-emitting units 21 is small, and the difference in brightness of different sub-light-emitting units 21 is small, thereby improving the light uniformity of the first light-emitting zone 20 and improving the light uniformity of the light-emitting device.

[0043] Optionally, the plurality of sub-light-emitting units 21 of the first light-emitting area 20 include a plurality of first sub-light-emitting units 211 and at least one second sub-light-emitting unit 212, wherein the light-emitting area of ​​the first sub-light-emitting unit 211 is different from the light-emitting area of ​​the second sub-light-emitting unit 212, and the light-emitting areas of all the first sub-light-emitting units 211 are the same; the light-emitting areas of each type of second sub-light-emitting unit 212 are the same, and the light-emitting areas of different types of second sub-light-emitting units 212 are different;

[0044] The resistance value of the short-circuit prevention resistor 30 of the first sub-light-emitting unit 211 is determined according to the equivalent resistance of the first sub-light-emitting unit 211 when it is not short-circuited, the equivalent resistance of the first sub-light-emitting unit 211 when it is short-circuited, and the number of sub-light-emitting units 21 in the first light-emitting area 20;

[0045] The resistance value of the anti-short-circuit resistor 30 of the second sub-light-emitting unit 212 is determined according to the resistance value of the anti-short-circuit resistor 30 of the first sub-light-emitting unit 211, the light-emitting area of ​​each sub-light-emitting unit 21 in the first light-emitting zone 20, the current density parameter of each sub-light-emitting unit 21 in the first light-emitting zone 20, and the ratio of the maximum current density to the minimum current density of the sub-light-emitting units 21 with different light-emitting areas in the first light-emitting zone 20.

[0046] The first sub-light emitting unit 211 is a sub-light emitting unit 21 of a regular area in the first light emitting area 20, and the number of the first sub-light emitting units 211 in the first light emitting area 20 is the largest. The first light emitting area 20 may include one second sub-light emitting unit 212, two second sub-light emitting units 212, or multiple second sub-light emitting units 212, and the number of each second sub-light emitting unit 212 may be one or more.

[0047] It can be assumed that all sub-light-emitting units 21 in the first light-emitting area 20 are first sub-light-emitting units 211, and the equivalent resistance R when the first sub-light-emitting unit 211 is short-circuited can be determined by simulation or experiment. cell-s , calculate the equivalent resistance R of the first sub-light emitting unit 211 when it is working normally cell-org When a first sub-light emitting unit 211 is short-circuited, all the first sub-light emitting units 211 that are not short-circuited are connected in series with the anti-short-circuit resistor 30, and then the parallel resistance is (Rcell-org +R cell-spl ) / (n-1), where n is the number of all sub-light-emitting units 21 in the first light-emitting area 20. The series resistance of the short-circuited first sub-light-emitting unit 211 and the anti-short-circuit resistor is R cell-s +R cell-spl According to the shunt formula of the parallel resistor, the current flowing through the short-circuited first sub-light-emitting unit 211 when the first sub-light-emitting unit 211 is short-circuited is calculated, and the ratio of the current to the total current input into the first light-emitting area 20 is set to be less than or equal to the set value, thereby calculating the anti-short-circuit resistance of the first sub-light-emitting unit 211.

[0048] Optionally, the resistance of the short-circuit protection resistor 30 of the first sub-light-emitting unit 211 is determined according to the following formula:

[0049]

[0050] Among them, A is a fixed value less than or equal to the set value, R cell-org is the equivalent resistance of the first sub-light emitting unit 211, R cell-spl is the resistance value of the short-circuit protection resistor 30 of the first sub-light-emitting unit 211, R cell-s is the equivalent resistance of the first sub-light-emitting unit 211 when it is short-circuited, and n is the number of the sub-light-emitting units 21 in the first light-emitting area 20 .

[0051] Specifically, assuming that all sub-light-emitting units 21 of the first light-emitting area 20 are first sub-light-emitting units 211, the current input to the first light-emitting area 20 is I1, and one first sub-light-emitting unit 21 in the first light-emitting area 20 is short-circuited, and the short-circuit current is I2, then according to the shunt formula of the parallel resistor, the short-circuit current of the short-circuited first sub-light-emitting unit 211 can be calculated as

[0052] When the short-circuit current is less than the set value, the brightness of the first light-emitting area is relatively uniform, and the A is smaller than a set value, and the value of A can be set according to the luminous brightness requirement. After setting the value of A, the resistance value of the anti-short-circuit resistor of the first sub-light-emitting unit is calculated according to the above formula.

[0053] In addition, when the resistance value of the anti-short-circuit resistor 30 of the second sub-light-emitting unit 212 is determined, the actual current density of each sub-light-emitting unit 21 is an expression including the light-emitting area, current density parameter and anti-short-circuit resistor of each sub-light-emitting unit 21, and the resistance value of the anti-short-circuit resistor 30 of the first sub-light-emitting unit 211 can be substituted into the expression, then the actual current density of each sub-light-emitting unit 21 is an expression including the light-emitting area, current density parameter and anti-short-circuit resistor 30 of each sub-light-emitting unit 21. According to the expression, the anti-short-circuit resistor of the second sub-light-emitting unit 212 is calculated.

[0054] This embodiment determines the resistance value of the anti-short-circuit resistor 30 of the first sub-light-emitting unit 211 according to the equivalent resistance of the first sub-light-emitting unit 211 when it is not short-circuited, the equivalent resistance of the first sub-light-emitting unit 211 when it is short-circuited, and the number of sub-light-emitting units 21 in the first light-emitting area 20, so that the iterative process for determining the resistance value of the anti-short-circuit resistor of the second sub-light-emitting unit 211 is simpler, reducing the difficulty of calculation.

[0055] Optionally, A is less than or equal to 10%.

[0056] Specifically, when A is less than or equal to 10%, the current lost by the short-circuited sub-light-emitting unit does not exceed 10% of the overall current, thereby ensuring that the overall brightness does not decay too much and ensuring the uniformity of light emission in the first light-emitting area.

[0057] Optionally, within the set brightness range, the value of the equivalent resistance of each sub-light emitting unit 21 and the value of the current density of the sub-light emitting unit 21 satisfy the first relationship: R 等效 =a*J b , where R 等效 is the equivalent resistance, J is the current density, a and b are current density parameters, and at least one of a and b of the sub-light emitting units 21 with different light emitting areas is different.

[0058] Specifically, the set brightness range can be determined according to the light-emitting characteristics of the sub-light-emitting unit 21, and the first relational expression can be determined by simulation or experiment. The light-emitting brightness range of the sub-light-emitting unit 21 in normal light emission and short circuit of this embodiment is within the set brightness range, and the equivalent resistance of the sub-light-emitting unit 21 and the current density of the sub-light-emitting unit 21 satisfy the first relational expression.

[0059] Optionally, the maximum current density and the minimum current density are determined according to the equivalent resistance of all sub-light-emitting units 21 of each light-emitting area obtained through multiple iterations and the light-emitting area of ​​each sub-light-emitting unit 21;

[0060] In the first iteration, the first iteration equivalent resistance of all sub-light-emitting units 21 of each light-emitting area is determined according to the initial preset current density, and the first iteration equivalent current density of all sub-light-emitting units 21 of each light-emitting area is determined according to each first iteration equivalent resistance and the light-emitting area of ​​each sub-light-emitting unit 21;

[0061] In the second iteration, the second iteration equivalent resistance of all sub-light-emitting units 21 of each light-emitting area is determined according to the first iteration equivalent current density, and the second iteration equivalent current density of all sub-light-emitting units 21 of each light-emitting area is determined according to each second iteration equivalent resistance and the light-emitting area of ​​each sub-light-emitting unit 21;

[0062] The nth iteration equivalent resistance of all sub-light-emitting units 21 of each light-emitting area is obtained by analogy.

[0063] Specifically, assuming that the current density during normal operation is J0, the luminous area of ​​the sub-light-emitting unit 21 of the first luminous area (the sub-light-emitting unit 21 of the normal luminous area) is S1, the anti-short-circuit resistor is R1, and the number is n1; the luminous area of ​​the sub-light-emitting unit 21 of the second luminous area is S2, the anti-short-circuit resistor is R2, and the number is n2; the luminous area of ​​the sub-light-emitting unit 21 of the third luminous area is S3, the anti-short-circuit resistor is R3, and the number is n3; and so on to S n , R n , n n .

[0064] Within a normal working current range within a certain brightness range, the value of the equivalent resistance of the sub-light emitting unit 21 and the value of the current density conform to an exponential relationship, R 等效 =a*J b First, assume that the current density in each pixel is J.

[0065] The first iteration calculation is: the parallel resistance R of the equivalent resistance of all sub-light-emitting units 21 with a light-emitting area of ​​S1 S11 =(a1*J0 b1 +R1) / n1; the parallel resistance R of the equivalent resistance of all sub-light-emitting units 21 with a light-emitting area of ​​S2 S21 =(a2*J0 b2 + R2) / n2, and so on to calculate the parallel resistance R of the equivalent resistance of all sub-light-emitting units 21 with a light-emitting area of ​​S3. S31 , the parallel resistance R of the equivalent resistance of all sub-light-emitting units 21 with a light-emitting area of ​​S4 S41 …….

[0066] Assuming that the current input to the first light-emitting area is 1, the current divided by the sub-light-emitting unit 21 of each light-emitting area is calculated according to the current division formula of multiple parallel resistors, and then the current density of the sub-light-emitting unit of each light-emitting area is calculated. Exemplarily, when the first light-emitting area includes three sub-light-emitting units 21 with different light-emitting areas, the parallel resistance of the three sub-light-emitting units 21 with different light-emitting areas is R 总 =(R S11 *R S21 *R S31 ) / (R S21 *R S31 +R S11 *R S31 +R S11* R S21 ), the current divided by the parallel resistance of all sub-light-emitting units with a light-emitting area of ​​S1 is 1*(R 总 / R S11 )=(R S21 *R S31 ) / (R S21 *R S31 +R S11 *R S31+ R S11* R S21 ). Similarly, when the light-emitting area includes more than three sub-light-emitting units 21 with different light-emitting areas, the current divided by the parallel resistance of all sub-light-emitting units with a light-emitting area of ​​S1 is (R S21 *R S31 …) / (R S21 *R S31 *R S41 ……+R S11 *R S31 *R S41 …+R S11 *R S21 *R S41 …+…), so that the current density J of the sub-light-emitting unit 21 with a light-emitting area of ​​S1 can be obtained. 11 Similarly, the current divided by the parallel resistance of all sub-light-emitting units 21 with a light-emitting area of ​​S2 is calculated, and the current density J of the sub-light-emitting unit 21 with a light-emitting area of ​​S2 is obtained. 21 , the current divided by the parallel resistance of all sub-light-emitting units 21 with a light-emitting area of ​​S3 is obtained, and the current density J of the sub-light-emitting unit 21 with a light-emitting area of ​​S3 is obtained. 31 , the current divided by the parallel resistance of all sub-light-emitting units 21 with a light-emitting area of ​​S4 is obtained, and the current density J of the sub-light-emitting unit 21 with a light-emitting area of ​​S4 is obtained. 41 …….

[0067] Then the second iteration is performed: the parallel resistance R of the equivalent resistance of all sub-light-emitting units with a light-emitting area of ​​S1 S12 =(a1*J 11 b1 +R1) / n1; the parallel resistance R of the equivalent resistance of all sub-light-emitting units with a light-emitting area of ​​S2 S22 =(a2*J 21 b2 +R2) / n2, and so on to calculate the parallel resistance R of the equivalent resistance of all sub-light-emitting units with a light-emitting area of ​​S3 S31 , the parallel resistance R of the equivalent resistance of all sub-light-emitting units with a light-emitting area of ​​S4 S41 …….

[0068] Similarly, the current divided by the sub-light-emitting unit of each light-emitting area is calculated according to the current sharing formula of multiple parallel resistors, and then the current density of the sub-light-emitting unit of each light-emitting area is calculated. For example, the current divided by the parallel resistors of all sub-light-emitting units with a light-emitting area of ​​S1 is (R S22 *R S32 …) / (R S22 *R S32 *R S42 ……+R S12 *R S32 *R S42 …+R S12 *R S22 *R S42 …+…), and thus the current density J of the sub-light-emitting unit with a light-emitting area of ​​S1 is calculated. 12 Similarly, the current divided by the parallel resistance of all sub-light-emitting units with a light-emitting area of ​​S2 is calculated to obtain the current density J of the sub-light-emitting unit 21 with a light-emitting area of ​​S2. 22 , the current divided by the parallel resistance of all sub-light-emitting units with a light-emitting area of ​​S3 is obtained, and the current density J of the sub-light-emitting unit 21 with a light-emitting area of ​​S2 is obtained. 32 , the current divided by the parallel resistance of all sub-light-emitting units with a light-emitting area of ​​S4 is obtained, and the current density J of the sub-light-emitting unit 21 with a light-emitting area of ​​S2 is obtained. 42 …….

[0069] By analogy, in the nth iteration, the parallel resistance R of the equivalent resistance of all sub-light-emitting units 21 with a light-emitting area of ​​S1 is S11 =(a1*J 1(n-1) b1 +R1) / n1; the parallel resistance R of the equivalent resistance of all sub-light-emitting units 21 with a light-emitting area of ​​S2 S21 =(a2*J 2(n-1) b2+ R2) / n2, and so on to calculate the parallel resistance R of the equivalent resistance of all sub-light-emitting units 21 with a light-emitting area of ​​S3. S31 , the parallel resistance R of the equivalent resistance of all sub-light-emitting units 21 with a light-emitting area of ​​S4 S41 ……. Then the current density J of the sub-light-emitting unit 21 with a light-emitting area of ​​S1 at the nth iteration is obtained: 1n , the current density J of the sub-light emitting unit 21 with a light emitting area of ​​S2 2n , the current density J of the sub-light emitting unit 21 with a light emitting area of ​​S3 3n , the current density J of the sub-light emitting unit 21 with a light emitting area of ​​S4 4n …

[0070] After multiple iterations, the current density J of each sub-light-emitting unit 21 is 1n , J 2n ,J 3n ,J 4n … tends to be stable, where the ratio K of the maximum value to the minimum value is the brightness difference between different sub-light-emitting units. By setting K less than or equal to the ratio of the maximum current density to the minimum current density, the resistance of the anti-short-circuit resistor 30 of each sub-light-emitting unit 21 can be calculated.

[0071] In addition, since there are a large number of sub-light-emitting units (first sub-light-emitting units) in the normal light-emitting area, the resistance value of the anti-short-circuit resistor of the sub-light-emitting unit (first sub-light-emitting unit) in the normal light-emitting area can be determined in advance, and the resistance value of the anti-short-circuit resistor of other light-emitting areas can be calculated based on the ratio of the maximum current density and the minimum current density obtained by iteration.

[0072] Optionally, the ratio is set to a value less than or equal to 1.05.

[0073] Specifically, the ratio of the maximum current density to the minimum current density in all sub-light-emitting units reflects the maximum brightness difference between all sub-light-emitting units. By setting the ratio of the maximum current density to the minimum current density to be less than or equal to 1.05, the maximum brightness difference of the sub-light-emitting units in the first light-emitting area can be ensured to be small, thereby ensuring the uniformity of light emission of each sub-light-emitting unit in the first light-emitting area.

[0074] Optionally, the driving line 40 is in a grid shape, the sub-light emitting units 21 are arranged in the grid of the driving line 40, different sub-light emitting units 21 are arranged in different grids, and each sub-light emitting unit 21 is electrically connected to the driving line 40 through the lead 31;

[0075] The lead wire 31 is a short-circuit prevention resistor 30 .

[0076] Specifically, the lead wire 31 is disposed together with the sub-light emitting unit 21 in the grid, one end of the lead wire 31 is connected to the sub-light emitting unit 21 , and the other end of the lead wire 31 is electrically connected to the driving line 40 .

[0077] Optionally, at least one of lead width, lead length and lead thickness of the lead 31 connecting the sub-light emitting units 21 with different light emitting areas is different.

[0078] Specifically, the resistance of the lead 31 can be adjusted by setting the lead width, lead length and lead thickness of the lead 31 so that the resistance value of the anti-short-circuit resistor 30 of the sub-light-emitting units 21 with different light-emitting areas meets the requirements.

[0079] Figure 2 yes Figure 1 A cross-sectional view of the light emitting device along the section line AA, optionally, refer to Figure 2 The sub-light emitting unit 21 includes a first electrode 51, a light emitting functional layer 52 and a second electrode 53 which are sequentially stacked, and the second electrode 53 is arranged on a side of the light emitting functional layer 52 away from the substrate;

[0080] The second electrodes 53 of all sub-light emitting units 21 in the same first light emitting area are connected to each other, and the first electrodes 51 of the sub-light emitting units 21 are electrically connected to the first end of the short-circuit prevention resistor.

[0081] The second electrodes 53 of the sub-light-emitting units 21 in the same first light-emitting area are an integrated structure. The first electrodes 51 of the sub-light-emitting units 21 are arranged at intervals. The short-circuit protection resistor can be arranged in the same layer as the first electrode 51, or on the side of the first electrode 51 adjacent to the substrate 10. The driving line can be arranged in the same layer as the first electrode 51, or on the side of the first electrode 51 adjacent to the substrate 10.

[0082] The light-emitting functional layer 52 includes a first functional layer, an organic light-emitting layer and a second functional layer which are stacked in sequence; the first functional layer is arranged on a side of the organic light-emitting layer adjacent to the first electrode;

[0083] The first functional layer includes at least one of an electron injection layer, an electron transport layer and a hole blocking layer, and the second functional layer includes at least one of a hole injection layer, a hole transport layer and an electron blocking layer; or, the second functional layer includes at least one of an electron injection layer, an electron transport layer and a hole blocking layer, and the first functional layer includes at least one of a hole injection layer, a hole transport layer and an electron blocking layer.

[0084] Among them, the first electrode 51 is an anode and the second electrode 53 is a cathode, or the first electrode 51 is a cathode and the second electrode 53 is an anode. The second electrode 53 of the first light-emitting unit 10 and the second sub-light-emitting unit 20 can be an integral structure. When the first electrode 51 is a cathode and the second electrode 53 is an anode, the first functional layer includes at least one of an electron injection layer, an electron transport layer and a hole blocking layer, and the second functional layer includes at least one of a hole injection layer, a hole transport layer and an electron blocking layer. When the first electrode 51 is an anode and the second electrode 53 is a cathode, the second functional layer includes at least one of an electron injection layer, an electron transport layer and a hole blocking layer, and the first functional layer includes a hole injection layer, a hole transport layer and an electron blocking layer.

[0085] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0086] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A light emitting device, characterized in that: include: A substrate and at least one first light emitting area disposed on the substrate; Each of the first light-emitting areas includes a plurality of sub-light-emitting units, each of the sub-light-emitting units is electrically connected to a first end of an anti-short-circuit resistor, and a second end of the anti-short-circuit resistor connected to the sub-light-emitting units in the same first light-emitting area is electrically connected to the same driving line, and the driving line is used to transmit a driving signal to the sub-light-emitting units; at least some of the sub-light-emitting units in the first light-emitting area have different light-emitting areas; The resistance value of the anti-short-circuit resistor of the sub-light-emitting unit is determined according to the light-emitting area of ​​each of the sub-light-emitting units in the first light-emitting zone, the current density parameter of the sub-light-emitting unit, and the ratio of the maximum current density to the minimum current density of the sub-light-emitting units with different light-emitting areas in the first light-emitting zone; wherein the current density parameter is a relationship parameter between the current density of the sub-light-emitting unit and the equivalent resistance.

2. The light emitting device according to claim 1, characterized in that: The plurality of sub-light-emitting units in the first light-emitting area include a plurality of first sub-light-emitting units and at least one second sub-light-emitting unit, wherein the light-emitting area of ​​the first sub-light-emitting unit is different from the light-emitting area of ​​the second sub-light-emitting unit, and the light-emitting areas of all the first sub-light-emitting units are the same; the light-emitting areas of each type of second sub-light-emitting unit are the same, and the light-emitting areas of different types of second sub-light-emitting units are different; The resistance value of the anti-short-circuit resistor of the first sub-light-emitting unit is determined according to the equivalent resistance of the first sub-light-emitting unit when it is not short-circuited, the equivalent resistance of the first sub-light-emitting unit when it is short-circuited, and the number of sub-light-emitting units in the first light-emitting area; The resistance value of the anti-short-circuit resistor of the second sub-light-emitting unit is determined according to the resistance value of the anti-short-circuit resistor of the first sub-light-emitting unit, the light-emitting area of ​​each of the sub-light-emitting units in the first light-emitting zone, the current density parameter of each sub-light-emitting unit in the first light-emitting zone, and the ratio setting value of the maximum current density to the minimum current density of the sub-light-emitting units with different light-emitting areas in the first light-emitting zone.

3. The light emitting device according to claim 1, characterized in that: Within the set brightness range, the value of the equivalent resistance of each sub-light-emitting unit and the value of the current density of the sub-light-emitting unit satisfy the first relationship: R 等效 =a*J b , where R 等效 is the equivalent resistance, J is the current density, a and b are current density parameters, and at least one of a and b of the sub-light-emitting units with different light-emitting areas is different.

4. The light emitting device according to claim 1, characterized in that: The maximum current density and the minimum current density are determined according to the equivalent resistance of all sub-light-emitting units of each light-emitting area obtained through multiple iterations and the light-emitting area of ​​each sub-light-emitting unit; In the first iteration, the first iteration equivalent resistance of all sub-light-emitting units of each light-emitting area is determined according to the initial preset current density, and the first iteration equivalent current density of all sub-light-emitting units of each light-emitting area is determined according to each of the first iteration equivalent resistances and the light-emitting area of ​​each sub-light-emitting unit; In the second iteration, the second iteration equivalent resistance of all sub-light-emitting units of each light-emitting area is determined according to the first iteration equivalent current density, and the second iteration equivalent current density of all sub-light-emitting units of each light-emitting area is determined according to each of the second iteration equivalent resistances and the light-emitting area of ​​each sub-light-emitting unit; The nth iteration equivalent resistance of all sub-light-emitting units of each light-emitting area is obtained by analogy.

5. The light emitting device according to claim 2, characterized in that: The resistance value of the short-circuit protection resistor of the first sub-light-emitting unit is determined according to the following formula: Among them, A is a fixed value less than or equal to the set value, R cell-org is the equivalent resistance of the first sub-light-emitting unit, R cell-spl is the resistance value of the short-circuit protection resistor of the first sub-light-emitting unit, R cell-s is the equivalent resistance of the first sub-light-emitting unit when it is short-circuited, and n is the number of sub-light-emitting units in the first light-emitting area.

6. The light emitting device according to claim 5, characterized in that: A is less than or equal to 10%.

7. The light emitting device according to claim 1, characterized in that: The ratio setting value is less than or equal to 1.

05.

8. The light emitting device according to claim 1, characterized in that: The driving line is in a grid shape, the sub-light emitting units are arranged in the grid of the driving line, different sub-light emitting units are arranged in different grids, and each sub-light emitting unit is electrically connected to the driving line through a lead wire; The lead wire is the anti-short circuit resistor.

9. The light emitting device according to claim 8, characterized in that: At least one of the lead width, lead length and lead thickness of the leads connecting the sub-light emitting units with different light emitting areas is different.

10. The light emitting device according to claim 1, characterized in that: The sub-light-emitting unit comprises a first electrode, a light-emitting functional layer and a second electrode which are stacked in sequence, and the second electrode is arranged on a side of the light-emitting functional layer away from the substrate; The second electrodes of all sub-light-emitting units in the same first light-emitting area are connected to each other, and the first electrodes of the sub-light-emitting units are electrically connected to the first end of the short-circuit prevention resistor.

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