Pmoled display device and pmoled display adaptive enhancement method

Abstract

The application relates to the technical field of display, and discloses a PMOLED display device and a PMOLED display adaptive enhancement method, wherein a photoelectric conversion unit is additionally arranged to real-time sense ambient light intensity, and a compensation voltage which increases with the increase of the ambient light intensity is superimposed on an initial driving voltage through a voltage compensation circuit, so that adaptive dynamic compensation of PMOLED display brightness is realized; in the scene of strong ambient light such as outdoor strong light, the display brightness can be automatically improved, the problem that display content is difficult to be clearly recognized by a user due to the relatively insufficient display brightness of the existing PMOLED is effectively solved, the visibility and user experience in the strong light environment are obviously improved, and the core advantages of the PMOLED, such as simple structure and low cost, are reserved.

Description

Technical Field

[0001] This invention relates to the field of display technology, and more particularly to a PMOLED display device and a PMOLED display adaptive enhancement method. Background Technology

[0002] OLED (Organic Light Emitting Diode) displays are made using organic light-emitting diodes. Because OLEDs are self-emissive, they do not require a backlight and offer advantages such as high contrast, thinness, wide viewing angles, and fast response times. They can be made into flexible display panels and have a wide temperature range, making them a new application technology for next-generation flat panel displays. Currently, OLED technology is becoming increasingly mature, its market share is growing, and its development has become a significant trend in the display industry.

[0003] PMOLED, as an important branch of OLED technology, uses a passive matrix driving method for its pixels, which has the advantages of simple structure and low cost. However, PMOLED still has the following technical problems in practical applications: the brightness of PMOLED is determined by the driving voltage. When the ambient light is strong, the display brightness of PMOLED is relatively insufficient, making it difficult for users to clearly see the displayed content, especially in strong outdoor light environments.

[0004] Therefore, improvements to existing technologies are necessary. Summary of the Invention

[0005] This invention provides a PMOLED display device and a PMOLED display adaptive enhancement method to solve the problems existing in the prior art.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] In a first aspect, the present invention provides a PMOLED display device, including a pixel driving circuit, a PMOLED pixel unit, and further comprising:

[0008] A photoelectric conversion unit is used to sense ambient light and generate a compensation voltage; and,

[0009] A voltage compensation circuit is connected to the pixel driving circuit, the photoelectric conversion unit and the PMOLED pixel unit respectively. It is used to superimpose and compensate the initial driving voltage output by the pixel driving circuit according to the compensation voltage, and output the compensated target driving voltage to the PMOLED pixel unit.

[0010] The compensation voltage increases with increasing ambient light intensity.

[0011] Furthermore, in the PMOLED display device, the voltage compensation circuit includes a switching unit and a boost unit;

[0012] The switching unit is connected to the photoelectric conversion unit and the boost unit respectively, and is used to input the compensation voltage output by the photoelectric conversion unit to the boost unit;

[0013] The boost unit is connected to the pixel driving circuit and the PMOLED pixel unit respectively, and is used to superimpose the compensation voltage onto the initial driving voltage output by the pixel driving circuit, and output the compensated target driving voltage to the PMOLED pixel unit.

[0014] Furthermore, in the PMOLED display device, the switching unit includes a first switching transistor T1 and a second switching transistor T2;

[0015] The first terminal of the first switching transistor T1 is grounded, and the second terminal is connected to the boost unit.

[0016] The first end of the second switch T2 is connected to the photoelectric conversion unit, and the second end is connected to the boost unit;

[0017] The first switch T1 and the second switch T2 are alternately turned on by a PWM signal to alternately input the ground potential and the compensation voltage output by the photoelectric conversion unit to the boost unit.

[0018] Furthermore, in the PMOLED display device, the boost unit includes a first energy storage capacitor C1, a second energy storage capacitor C2, a third energy storage capacitor C3, a fourth energy storage capacitor C4, a first rectifier element D1, a second rectifier element D2, a third rectifier element D3, and a fourth rectifier element D4.

[0019] The anode of the first rectifier element D1 is connected to the pixel driving circuit, and the cathode is connected to the first terminal of the first capacitor C1 and the anode of the second rectifier element D2.

[0020] The second terminal of the first capacitor C1 is connected to the second terminal of the first switching transistor T1 and the second terminal of the second switching transistor T2, respectively.

[0021] The cathode of the second rectifier element D2 is connected to the first terminal of the third capacitor C3 and the anode of the third rectifier element D3;

[0022] The second terminal of the third capacitor C3 is grounded;

[0023] The cathode of the third rectifier element D3 is connected to the first terminal of the second capacitor C2 and the anode of the fourth rectifier element D4;

[0024] The second terminal of the second capacitor C2 is connected to the second terminal of the first switch T1 and the second terminal of the second switch T2, respectively;

[0025] The cathode of the fourth rectifier element D4 is connected to the first terminal of the fourth capacitor C4 and the PMOLED pixel unit;

[0026] The second terminal of the fourth capacitor C4 is grounded.

[0027] Furthermore, in the PMOLED display device, the first rectifier element D1, the second rectifier element D2, the third rectifier element D3, and the fourth rectifier element D4 are all diodes.

[0028] Furthermore, in the PMOLED display device, the photoelectric conversion unit includes a photodiode (PD);

[0029] The anode of the photodiode PD is connected to the first terminal of the second switch T2.

[0030] Furthermore, the PMOLED display device further includes a black matrix;

[0031] The photoelectric conversion unit is disposed in the black matrix.

[0032] Furthermore, the PMOLED display device further includes at least one color filter;

[0033] The black matrix has at least one through hole.

[0034] The color filter is disposed within the through hole.

[0035] In a second aspect, the present invention provides a PMOLED display adaptive enhancement method, implemented using the PMOLED display device provided in the first aspect above, the method comprising:

[0036] S1. The photoelectric conversion unit senses ambient light and generates a compensation voltage;

[0037] S2. Receive the initial driving voltage output by the pixel driving circuit through the voltage compensation circuit, and superimpose and compensate the initial driving voltage according to the compensation voltage to obtain the target driving voltage.

[0038] S3. Output the target driving voltage to the PMOLED pixel unit to drive the PMOLED pixel unit to emit light.

[0039] Furthermore, in the PMOLED display adaptive enhancement method, step S2 includes:

[0040] S21. Receive the initial driving voltage output by the pixel driving circuit through the voltage compensation circuit, and perform superimposed compensation on the initial driving voltage according to the compensation voltage.

[0041] S22. Repeat step S21 to perform superimposed compensation on the driving voltage after the previous superimposed compensation, until the number of repetitions reaches N, and the target driving voltage is obtained; where N is an integer greater than or equal to 2.

[0042] Compared with the prior art, the present invention has the following beneficial effects:

[0043] This invention provides a PMOLED display device and an adaptive enhancement method for PMOLED displays. By adding a photoelectric conversion unit to sense the ambient light intensity in real time, and superimposing the compensation voltage, which increases with the increase of ambient light intensity, onto the initial driving voltage via a voltage compensation circuit, adaptive dynamic compensation of PMOLED display brightness is achieved. In scenarios with strong ambient light, such as outdoor strong light, the display brightness can be automatically increased, effectively solving the problem that the display content is difficult for users to clearly identify due to the relatively insufficient display brightness of existing PMOLEDs. This significantly improves visibility and user experience in strong light environments, while retaining the core advantages of PMOLEDs, such as simple structure and low cost. Attached Figure Description

[0044] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0045] Figure 1 This is one of the functional module diagrams of a PMOLED display device provided in Embodiment 1 of the present invention;

[0046] Figure 2 This is the second functional module schematic diagram of a PMOLED display device provided in Embodiment 1 of the present invention;

[0047] Figure 3 This is a schematic diagram of the circuit principle of a PMOLED display device provided in Embodiment 1 of the present invention;

[0048] Figure 4 This is a timing diagram of the operation process of the voltage compensation circuit provided in Embodiment 1 of the present invention;

[0049] Figure 5 This is a schematic diagram of the structure of the black matrix, color filter, and photoelectric conversion unit provided in Embodiment 1 of the present invention;

[0050] Figure 6 This is a flowchart illustrating an adaptive enhancement method for PMOLED displays provided in Embodiment 2 of the present invention.

[0051] Figure label:

[0052] Pixel driving circuit 1, PMOLED pixel unit 2, photoelectric conversion unit 3, voltage compensation circuit 4, black matrix 5, color filter 6;

[0053] Switching unit 41, boosting unit 42. Detailed Implementation

[0054] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0055] Example 1

[0056] Please refer to Figure 1 This invention provides a PMOLED display device, which includes a conventional pixel driving circuit 1 and a PMOLED pixel unit 2. In the prior art, the initial driving voltage output by the pixel driving circuit 1 is usually directly applied to the PMOLED pixel unit 2 to drive it to emit light and display. However, this invention differs fundamentally from the prior art. While retaining the conventional structure described above, this invention innovatively adds the following components:

[0057] A photoelectric conversion unit 3, configured in the PMOLED display device, is used to sense changes in ambient light intensity in real time and generate a corresponding compensation voltage based on the sensed ambient light intensity; and,

[0058] A voltage compensation circuit 4 is connected to the pixel driving circuit 1, the photoelectric conversion unit 3, and the PMOLED pixel unit 2 respectively. It is used to receive the compensation voltage generated by the photoelectric conversion unit 3, and perform superposition compensation processing on the initial driving voltage output by the pixel driving circuit 1 according to the compensation voltage, and then output the compensated target driving voltage to the PMOLED pixel unit 2 to drive the PMOLED pixel unit 2 to emit light and display.

[0059] The amplitude of the compensation voltage increases accordingly with the increase of ambient light intensity. That is, the stronger the ambient light, the higher the compensation voltage generated by the photoelectric conversion unit 3, thereby ensuring that the target driving voltage output by the voltage compensation circuit 4 can be adaptively adjusted with the change of ambient light intensity.

[0060] This invention, by adding the photoelectric conversion unit 3, enables it to sense changes in ambient light intensity in real time and dynamically. The voltage compensation circuit 4 then superimposes a compensation voltage, which increases accordingly with increasing ambient light intensity, onto the initial driving voltage output by the pixel driving circuit 1, thereby achieving an adaptive dynamic compensation mechanism for PMOLED display brightness. When ambient light is strong, such as in outdoor strong light environments, the display brightness of the PMOLED pixel unit 2 automatically increases according to the increase in ambient light intensity. This effectively overcomes the technical defect in existing PMOLED display devices where insufficient display brightness makes it difficult for users to clearly discern the displayed content, significantly improving display visibility and user viewing experience in strong light environments and high-brightness backgrounds. Furthermore, since this invention only adds the photoelectric conversion unit 3 and the voltage compensation circuit 4, without changing the basic architecture of the PMOLED passive matrix drive, it fully retains the core competitive advantages of PMOLED: simple structure, mature technology, and low cost, possessing good practicality and market promotion value.

[0061] Please refer to Figure 2 In one embodiment of this invention, the voltage compensation circuit 4 further includes a switching unit 41 and a boost unit 42.

[0062] The switching unit 41 is connected to the photoelectric conversion unit 3 and the boost unit 42 respectively. The switching unit 41 is used to receive the compensation voltage generated by the photoelectric conversion unit 3 based on the ambient light intensity, and when it is in the on-state, transmits the compensation voltage to the boost unit 42, thereby realizing effective on-off control and signal transmission of the compensation voltage input path.

[0063] The boost unit 42 is connected to both the pixel driving circuit 1 and the PMOLED pixel unit 2. The boost unit 42 simultaneously receives the initial driving voltage output from the pixel driving circuit 1 and the compensation voltage transmitted via the switching unit 41. It then uses an internal voltage superposition mechanism to superimpose the compensation voltage onto the initial driving voltage, thereby increasing the amplitude of the driving voltage. This generates and outputs the compensated target driving voltage to the PMOLED pixel unit 2, thus driving the PMOLED pixel unit 2 to achieve higher brightness illumination under the enhanced driving voltage.

[0064] Please refer to Figure 3In one embodiment of this invention, the switching unit 41 further includes a first switching transistor T1 and a second switching transistor T2.

[0065] Specifically, the first terminal of the first switch transistor T1 is grounded, and the second terminal of the first switch transistor T1 is connected to the boost unit 42; the first terminal of the second switch transistor T2 is connected to the photoelectric conversion unit 3, and the second terminal of the second switch transistor T2 is connected to the boost unit 42.

[0066] The control terminals of the first switch T1 and the second switch T2 receive pulse width modulation (PWM) signals provided externally, and alternately turn on and off under the timing control of the PWM signals. The specific operation is as follows: When the first switch T1 is on, the second switch T2 is off. At this time, the boost unit 42 is connected to ground potential through the first switch T1, thereby inputting the ground potential to the boost unit 42. Conversely, when the second switch T2 is on, the first switch T1 is off. At this time, the boost unit 42 is connected to the photoelectric conversion unit 3 through the second switch T2, thereby inputting the compensation voltage output by the photoelectric conversion unit 3 to the boost unit 42.

[0067] Through the alternating conduction mechanism of the first switch T1 and the second switch T2 under the control of the PWM signal, the switching unit 41 can periodically and alternately send the ground potential and the compensation voltage output by the photoelectric conversion unit 3 to the boost unit 42, thereby providing a stable input voltage switching signal for the boost unit 42, ensuring that the boost unit 42 can effectively superimpose the compensation voltage onto the initial driving voltage, and realize accurate voltage compensation and boost functions.

[0068] Please refer to this again. Figure 3 In one embodiment of this invention, the boost unit 42 further includes a first energy storage capacitor C1, a second energy storage capacitor C2, a third energy storage capacitor C3, a fourth energy storage capacitor C4, a first rectifier element D1, a second rectifier element D2, a third rectifier element D3, and a fourth rectifier element D4.

[0069] Specifically, the anode of the first rectifier element D1 is connected to the pixel driving circuit 1, and the cathode of the first rectifier element D1 is connected to the first terminal of the first energy storage capacitor C1 and the anode of the second rectifier element D2, respectively; the second terminal of the first energy storage capacitor C1 is connected to the second terminal of the first switching transistor T1 and the second terminal of the second switching transistor T2, respectively; the cathode of the second rectifier element D2 is connected to the first terminal of the third energy storage capacitor C3 and the anode of the third rectifier element D3, respectively; the second terminal of the third energy storage capacitor C3 is grounded; the cathode of the third rectifier element D3 is connected to the first terminal of the second energy storage capacitor C2 and the anode of the fourth rectifier element D4, respectively; the second terminal of the second energy storage capacitor C2 is connected to the second terminal of the first switching transistor T1 and the second terminal of the second switching transistor T2, respectively; the cathode of the fourth rectifier element D4 is connected to the first terminal of the fourth energy storage capacitor C4 and the PMOLED pixel unit 2, respectively; the second terminal of the fourth energy storage capacitor C4 is grounded.

[0070] As a preferred embodiment, the first rectifier element D1, the second rectifier element D2, the third rectifier element D3, and the fourth rectifier element D4 can be implemented using rectifier devices with unidirectional conductivity, such as diodes; the first switch T1 and the second switch T2 can be implemented using thin-film transistors (TFTs), metal-oxide-semiconductor field-effect transistors (MOSFETs), or other semiconductor switching devices with controllable switching functions. Their specific types can be flexibly selected according to the actual process technology and circuit design requirements. For example, N-type thin-film transistors (N-TFTs), P-type thin-film transistors (P-TFTs), N-channel MOSFETs (NMOS), or P-channel MOSFETs (PMOS) can be used, as long as the switching on and off functions can be achieved through complementary control by PWM signals. This invention does not limit this.

[0071] Please refer to this again. Figure 3 In one embodiment of this invention, the photoelectric conversion unit 3 further includes a photodiode PD. The anode of the photodiode PD is connected to the first terminal of the second switching transistor T2, and the cathode of the photodiode PD is grounded. It is used to generate a photocurrent under ambient light irradiation, and based on the photocurrent, a compensation voltage corresponding to the ambient light intensity is formed across the photodiode PD.

[0072] The working principle of the voltage compensation circuit 4 will be explained in detail below:

[0073] Without the photodiode PD in the photoelectric conversion unit 3 and without the voltage compensation circuit 4, the initial driving voltage output by the pixel driving circuit 1 will be directly applied to the PMOLED pixel unit 2. At this time, the PMOLED pixel unit 2 can only obtain the basic pixel driving voltage, that is, the initial driving voltage. Its display brightness is completely determined by the initial driving voltage and cannot be adaptively adjusted according to changes in ambient light.

[0074] When the voltage compensation circuit 4 is in normal working condition, taking double superposition compensation (i.e., double voltage boost) as an example, its complete working process can be divided into the following four stages. Please refer to the following for details. Figure 3 To understand the circuit topology shown:

[0075] Phase 1: Assume the initial driving voltage input to the pixel driving circuit 1 is 5V. At this time, the first switch T1 is turned on and the second switch T2 is turned off, pulling node V1 down to ground (0V). The initial driving voltage charges the first energy storage capacitor C1 via the first rectifier D1, charging the voltage at the first terminal of the first energy storage capacitor C1 to 5V. Since the second terminal of the first energy storage capacitor C1 is connected to node V1 (0V), a 5V voltage difference is established across the first energy storage capacitor C1. Simultaneously, the initial driving voltage charges the third energy storage capacitor C3 via the second rectifier D2, charging the voltage at node V2 to 5V. That is, the voltage at the first terminal of the third energy storage capacitor C3 is equal to the initial driving voltage (5V), and the second terminal of the third energy storage capacitor C3 is grounded. Furthermore, the voltage at node V2 charges the second energy storage capacitor C2 via the third rectifier element D3. Since the second terminal of the second energy storage capacitor C2 is grounded (0V) through the first switch T1, the first terminal of the second energy storage capacitor C2 is charged to 5V, establishing a 5V voltage difference across the second energy storage capacitor C2. Subsequently, the voltage at the first terminal of the second energy storage capacitor C2 charges the fourth energy storage capacitor C4 via the fourth rectifier element D4, charging the voltage at node V3 to 5V, meaning the voltage at the first terminal of the fourth energy storage capacitor C4 is equal to the initial drive voltage (5V).

[0076] Second stage: The first switch T1 is turned off and the second switch T2 is turned on. At this time, ambient light illuminates the photodiode PD, causing it to generate a photocurrent and form a compensation voltage across its terminals (assuming this compensation voltage is 1V). The voltage at node V1 is raised to 1V. Since the first energy storage capacitor C1 and the second energy storage capacitor C2 have established a voltage difference of 5V in the first stage, according to the characteristic that the voltage across a capacitor cannot change abruptly, when the voltage at node V1 jumps from 0V to 1V, the voltage at the first terminal of the first energy storage capacitor C1 correspondingly rises from 5V to 6V, and the voltage at the first terminal of the second energy storage capacitor C2 also correspondingly rises from 5V to 6V. At this time, the voltage at the first terminal of the first energy storage capacitor C1, after being boosted, is used by the second rectifier element D2 to supplement the charging of the third energy storage capacitor C3, raising the voltage at node V2 from 5V to 6V. Simultaneously, the voltage at the first terminal of the second energy storage capacitor C2, after being boosted, is used by the fourth rectifier element D4 to supplement the charging of the fourth energy storage capacitor C4, raising the voltage at node V3 from 5V to 6V. This completes the first superposition compensation, i.e., the first voltage boost.

[0077] Phase 3: The first switch T1 is turned on again, and the second switch T2 is turned off. At this time, the photodiode PD no longer provides compensation voltage to node V1 due to being blocked or the circuit switching, and node V1 returns to ground potential (0V). The voltage at the second terminal of the first energy storage capacitor C1 returns to the initial driving voltage (5V). Since the third energy storage capacitor C3 and the fourth energy storage capacitor C4 have charge retention and voltage stabilization functions, the voltages at nodes V2 and V3 are still maintained at 6V under the reverse cutoff effect of the third rectifier element D3 and the fourth rectifier element D4. At this time, the third rectifier element D3 is turned on because node V2 (6V) is higher than the second terminal (0V) of the second energy storage capacitor C2, clamping the second terminal of the second energy storage capacitor C2 to 6V, so that the voltage difference across the second energy storage capacitor C2 increases from 5V in the first phase to 6V.

[0078] Fourth stage: The first switch T1 is turned off again and the second switch T2 is turned on. At this time, due to ambient light illuminating the photodiode PD, the compensation voltage is generated again, and the voltage of node V1 is raised to 1V again. Since the voltage difference across the second energy storage capacitor C2 has been increased to 6V in the third stage, according to the principle of capacitor voltage boost, when node V1 jumps from 0V to 1V, the voltage at the first end of the second energy storage capacitor C2 is further boosted to 7V (6V+1V). This boosted voltage is used to recharge the fourth energy storage capacitor C4 through the fourth rectifier element D4, causing the voltage of node V3 to rise from 6V to 7V. Thus, the second superposition compensation, i.e., the second voltage boost, is completed. Finally, the boost unit 42 outputs the target driving voltage (7V) obtained after boosting to the PMOLED pixel unit 2 through node V3 to drive it to perform higher brightness light emission display.

[0079] It should be noted that, after the two voltage boosting processes described above, the PMOLED pixel unit 2 receives an additional 2V voltage compensation on top of the initial driving voltage (5V), which significantly improves its luminous brightness and thus greatly improves the display effect in strong light environments. The reason for exemplarily employing a two-stage voltage boosting technique in this embodiment is that the energy conversion efficiency of ambient light into electrical signals (compensation voltage) via photodiodes is relatively low, and the voltage increase obtained by a single boost is limited. By using two (or even more) boosting processes, the boosting effect can be significantly accumulated, making the enhancement of display brightness more significant and thus better meeting the visibility requirements in strong outdoor light environments.

[0080] Figure 4 A timing diagram illustrating the above-described operation is shown. Initially, the first switch T1 is turned on, the voltage of node V1 is 0V, and the voltages of nodes V2 and V3 are both 5V. At time t1, the second switch T2 is turned on, raising the voltage of node V1 to 1V, and the voltages of nodes V2 and V3 to 6V. At time t2, the first switch T1 is turned on again, node V1 returns to 0V, while nodes V2 and V3 maintain a constant voltage of 6V under the voltage regulation of the third energy storage capacitor C3 and the fourth energy storage capacitor C4. At time t3, due to the unidirectional conductivity and charge retention of the second rectifier element D2 and the third rectifier element D3, node V2 continues to maintain 6V, while node V3 rises to 7V under the further boosting effect of the second energy storage capacitor C2. This 7V target driving voltage is then supplied to the PMOLED pixel unit 2, thereby achieving adaptive enhancement of display brightness.

[0081] Please refer to Figure 5In one embodiment of this invention, the PMOLED display device further includes a black matrix 5. The black matrix 5 is disposed within the display area of ​​the PMOLED display device, used to define the boundary areas of each sub-pixel unit, prevent light crosstalk between adjacent pixels, and improve display contrast. The photoelectric conversion unit 3 is disposed within the film layer of the black matrix 5, that is, the photoelectric conversion unit 3 is integrated and arranged in the non-transparent area of ​​the black matrix 5. By embedding the photoelectric conversion unit 3 within the existing structural space of the black matrix 5, there is no need to add an additional independent film layer or occupy an additional panel layer for the photoelectric conversion unit 3, thereby effectively avoiding the problem of increased overall thickness of the display panel caused by adding a photoelectric conversion functional layer; at the same time, since the photoelectric conversion unit 3 is located within the light-shielding area of ​​the black matrix 5, it will not block the effective light-emitting area of ​​the PMOLED pixel unit 2, nor will it obstruct the normal emission path of the emitted light, thus not negatively affecting the transmittance and aperture ratio of the display panel. While ensuring the normal operation of the ambient light sensing function, it fully guarantees the brightness and transmittance of the displayed image, which is beneficial for achieving a thinner, lighter, and more integrated design of the display device.

[0082] Please refer to this again. Figure 5 In one embodiment of this invention, the PMOLED display device further includes at least one color filter 6 (e.g., Figure 5 The black matrix 5 includes a red filter, a green filter, and a blue filter. The black matrix 5 has at least one through-hole (or opening, cutout area), and the color filter 6 is correspondingly disposed within the through-hole of the black matrix 5. Specifically, in addition to fulfilling the basic functions of light blocking, defining pixel boundaries, and preventing optical crosstalk, the black matrix 5 provides mounting space for the color filter 6 by creating the through-hole in its film layer. The color filter 6, embedded in the through-hole, filters the light emitted by the PMOLED pixel unit 2 to achieve color display functionality. By integrating the color filter 6 into the existing through-hole structure of the black matrix 5, the black matrix 5 can perform both light-shielding and filter support functions, significantly optimizing the internal structural layout and space utilization of the display panel. This avoids structural overlap or spatial conflict between the color filter 6 and the black matrix 5 in the in-plane direction, thereby achieving the integration of color filtering functions without increasing the thickness of additional film layers, and further promoting the optimized development of display devices towards high integration and ultra-thinness.

[0083] Although this invention frequently uses terms such as pixel driving circuit and PMOLED pixel unit, the possibility of using other terms is not excluded. These terms are used merely for the convenience of describing and explaining the essence of this invention; interpreting them as any additional limitation would contradict the spirit of this invention.

[0084] Example 2

[0085] Please refer to Figure 6 This is a flowchart illustrating an adaptive enhancement method for PMOLED displays provided in an embodiment of the present invention. The method is implemented using the PMOLED display device provided in Embodiment 1 above. Its aim is to dynamically compensate for and enhance display brightness by adaptively adjusting the driving voltage of the PMOLED pixel units by sensing changes in ambient light intensity in real time. The method specifically includes the following steps:

[0086] S1. The photoelectric conversion unit senses ambient light and generates a compensation voltage.

[0087] It should be noted that in this step, the photoelectric conversion unit is configured within the display area of ​​the PMOLED display device to continuously and in real-time sense changes in ambient light intensity. When ambient light shines on the photoelectric conversion unit, the unit converts the received light signal into a corresponding electrical signal based on the photoelectric effect, generating a compensation voltage that is positively correlated with the ambient light intensity. Specifically, the amplitude of the compensation voltage increases with increasing ambient light intensity and decreases with decreasing ambient light intensity, thereby achieving real-time quantification and electrical characterization of ambient light intensity. This compensation voltage serves as the reference signal for subsequent voltage superposition compensation, providing a control input that dynamically matches the ambient light intensity for the entire adaptive enhancement method.

[0088] S2. Receive the initial driving voltage output by the pixel driving circuit through the voltage compensation circuit, and superimpose and compensate the initial driving voltage according to the compensation voltage to obtain the target driving voltage.

[0089] It should be noted that in this step, the voltage compensation circuit simultaneously receives two input signals: one is the initial driving voltage output from the pixel driving circuit, which is the base driving voltage of the PMOLED pixel unit in normal operating mode; the other is the compensation voltage generated by the photoelectric conversion unit in S1. Internally, the voltage compensation circuit, through the coordinated operation of its switching unit and boost unit, superimposes the compensation voltage onto the initial driving voltage. Specifically, under the timing control of the PWM signal, the switching unit periodically alternately inputs ground potential and the compensation voltage to the boost unit; the boost unit accumulates and superimposes the compensation voltage onto the initial driving voltage in stages, thereby generating a target driving voltage with an amplitude higher than the initial driving voltage. The amplitude of the target driving voltage is determined by the sum of the initial driving voltage and the compensation voltage after boosting, and this target driving voltage can adaptively and dynamically adjust with changes in ambient light intensity.

[0090] S3. Output the target driving voltage to the PMOLED pixel unit to drive the PMOLED pixel unit to emit light.

[0091] It should be noted that in this step, the voltage compensation circuit outputs the target driving voltage obtained after superposition compensation in S2 to the PMOLED pixel unit as the actual operating driving voltage of the PMOLED pixel unit. Since the amplitude of the target driving voltage has been adaptively increased according to the ambient light intensity, the brightness of the PMOLED pixel unit under this enhanced driving voltage is correspondingly higher than that driven only by the initial driving voltage. When the ambient light is strong, the target driving voltage increases accordingly, and the brightness of the PMOLED pixel unit automatically increases, effectively offsetting the weakening effect of ambient light on display contrast; when the ambient light is weak, the target driving voltage decreases accordingly, and the display brightness returns to a normal level, avoiding unnecessary power consumption increases. Thus, through the sequential execution and cyclic feedback of S1-S3, adaptive dynamic enhancement of PMOLED display brightness is achieved, ensuring that the displayed content can be clearly recognized by the user under different lighting conditions.

[0092] In summary, the PMOLED display adaptive enhancement method provided in this invention forms a closed-loop control process of "ambient light sensing - voltage compensation - brightness enhancement" through the coordinated operation of the photoelectric conversion unit, voltage compensation circuit, and PMOLED pixel unit. This method does not require changes to the basic architecture of the PMOLED passive matrix driver, nor does it require manual adjustment of display parameters by the user. It can automatically and in real-time complete adaptive compensation of display brightness according to changes in ambient light, significantly improving display visibility and user experience in strong light environments, while also taking into account the technical advantages of low power consumption and low cost.

[0093] In one embodiment of this example, step S2 can be further refined to include the following sub-steps:

[0094] S21. Receive the initial driving voltage output by the pixel driving circuit through the voltage compensation circuit, and perform superimposed compensation on the initial driving voltage according to the compensation voltage.

[0095] It should be noted that in this sub-step, the voltage compensation circuit simultaneously receives the initial driving voltage output from the pixel driving circuit and the compensation voltage generated by the photoelectric conversion unit. Specifically, the switching unit inside the voltage compensation circuit is periodically and alternately turned on under the timing drive of the PWM signal, thereby alternately inputting the ground potential and the compensation voltage to the boost unit; the boost unit superimposes the compensation voltage onto the initial driving voltage, completing the first superposition compensation (i.e., the first boost), to obtain the driving voltage after the first superposition compensation. The amplitude of the driving voltage after the first superposition compensation is higher than the initial driving voltage.

[0096] S22. Repeat step S21 to perform superimposed compensation on the driving voltage after the previous superimposed compensation, until the number of repetitions reaches N, and the target driving voltage is obtained; where N is an integer greater than or equal to 2.

[0097] It should be noted that in this sub-step, because the energy conversion efficiency of the photoelectric conversion unit in converting ambient light into electrical signals (i.e., compensation voltage) is relatively low, the voltage boost obtained by a single superposition compensation is relatively limited, making it difficult to provide a sufficiently significant brightness enhancement effect for the PMOLED pixel unit in a strong light environment. Therefore, this embodiment repeats step S21, utilizing the charge retention characteristics of the energy storage capacitor inside the boost unit and the unidirectional conduction characteristics of the rectifier element, to superimpose the compensation voltage again on the driving voltage obtained after the previous superposition compensation, thereby achieving iterative or cascaded multiple voltage boosts.

[0098] Specifically, during each repetition, the switching unit, under the complementary control of the PWM signal, continues to alternately supply ground potential and the compensation voltage to the boost unit. The first, second, third, and fourth energy storage capacitors within the boost unit accumulate voltage increments step by step during alternating charging and discharging, ensuring that each superimposed compensation further increases the output voltage based on the previous boost result. After N repetitions, the target driving voltage output by the boost unit achieves a cumulative increase of N times compared to the single compensation voltage increment, resulting in a target driving voltage with a significantly increased amplitude.

[0099] Preferably, N can be set to 2, meaning the target driving voltage is obtained after two superimposed compensations (two voltage boosts). This setting achieves a better balance between circuit complexity, power consumption control, and voltage boosting effect. By setting N to an integer greater than or equal to 2, this embodiment significantly improves the cumulative effect of voltage compensation without significantly increasing circuit structure complexity and manufacturing costs. This allows the PMOLED pixel unit to obtain a more sufficient driving voltage boost in application scenarios with strong ambient light, such as outdoor strong light, thereby significantly enhancing display brightness and ensuring that the displayed content maintains high visibility and recognizability even in strong light environments.

[0100] Finally, it should be noted that although the above embodiments have been described in the description and drawings of this invention, this should not limit the scope of patent protection of this invention. Any technical solutions that are based on the essential concept of this invention, utilize the content described in the description and drawings of this invention to make equivalent structural or procedural substitutions or modifications, as well as the direct or indirect application of the technical solutions of the above embodiments to other related technical fields, are all included within the scope of patent protection of this invention.

Claims

1. A PMOLED display device, comprising a pixel driving circuit (1) and a PMOLED pixel unit (2), characterized in that, Also includes: A photoelectric conversion unit (3) is used to sense ambient light and generate a compensation voltage; and, The voltage compensation circuit (4) is connected to the pixel driving circuit (1), the photoelectric conversion unit (3) and the PMOLED pixel unit (2) respectively. It is used to superimpose and compensate the initial driving voltage output by the pixel driving circuit (1) according to the compensation voltage, and output the compensated target driving voltage to the PMOLED pixel unit (2). The compensation voltage increases with increasing ambient light intensity.

2. The PMOLED display device according to claim 1, characterized in that, The voltage compensation circuit (4) includes a switching unit (41) and a boost unit (42). The switching unit (41) is connected to the photoelectric conversion unit (3) and the boost unit (42) respectively, and is used to input the compensation voltage output by the photoelectric conversion unit (3) to the boost unit (42). The boost unit (42) is connected to the pixel driving circuit (1) and the PMOLED pixel unit (2) respectively, and is used to superimpose the compensation voltage onto the initial driving voltage output by the pixel driving circuit (1) and output the compensated target driving voltage to the PMOLED pixel unit (2).

3. The PMOLED display device according to claim 2, characterized in that, The switching unit (41) includes a first switching transistor T1 and a second switching transistor T2; The first terminal of the first switch transistor T1 is grounded, and the second terminal is connected to the boost unit (42); The first end of the second switch T2 is connected to the photoelectric conversion unit (3), and the second end is connected to the boost unit (42); The first switch T1 and the second switch T2 are alternately turned on by a PWM signal to alternately input the ground potential and the compensation voltage output by the photoelectric conversion unit (3) to the boost unit (42).

4. The PMOLED display device according to claim 3, characterized in that, The boost unit (42) includes a first energy storage capacitor C1, a second energy storage capacitor C2, a third energy storage capacitor C3, a fourth energy storage capacitor C4, a first rectifier element D1, a second rectifier element D2, a third rectifier element D3, and a fourth rectifier element D4; The anode of the first rectifier element D1 is connected to the pixel driving circuit (1), and the cathode is connected to the first terminal of the first capacitor C1 and the anode of the second rectifier element D2. The second terminal of the first capacitor C1 is connected to the second terminal of the first switching transistor T1 and the second terminal of the second switching transistor T2, respectively. The cathode of the second rectifier element D2 is connected to the first terminal of the third capacitor C3 and the anode of the third rectifier element D3; The second terminal of the third capacitor C3 is grounded; The cathode of the third rectifier element D3 is connected to the first terminal of the second capacitor C2 and the anode of the fourth rectifier element D4; The second terminal of the second capacitor C2 is connected to the second terminal of the first switch T1 and the second terminal of the second switch T2, respectively; The cathode of the fourth rectifier element D4 is connected to the first end of the fourth capacitor C4 and the PMOLED pixel unit (2); The second terminal of the fourth capacitor C4 is grounded.

5. The PMOLED display device according to claim 4, characterized in that, The first rectifier element D1, the second rectifier element D2, the third rectifier element D3, and the fourth rectifier element D4 are all diodes.

6. The PMOLED display device according to claim 3, characterized in that, The photoelectric conversion unit (3) includes a photodiode (PD); The anode of the photodiode PD is connected to the first terminal of the second switch T2.

7. The PMOLED display device according to claim 1, characterized in that, It also includes the black matrix (5); The photoelectric conversion unit (3) is disposed in the black matrix (5).

8. The PMOLED display device according to claim 7, characterized in that, It also includes at least one color filter (6); The black matrix (5) has at least one through hole. The color filter (6) is disposed within the through hole.

9. An adaptive enhancement method for PMOLED displays, characterized in that, The method comprises: using a PMOLED display device as described in any one of claims 1-8 S1. The photoelectric conversion unit senses ambient light and generates a compensation voltage; S2. Receive the initial driving voltage output by the pixel driving circuit through the voltage compensation circuit, and superimpose and compensate the initial driving voltage according to the compensation voltage to obtain the target driving voltage. S3. Output the target driving voltage to the PMOLED pixel unit to drive the PMOLED pixel unit to emit light.

10. The PMOLED display adaptive enhancement method according to claim 9, characterized in that, S2 includes: S21. Receive the initial driving voltage output by the pixel driving circuit through the voltage compensation circuit, and perform superimposed compensation on the initial driving voltage according to the compensation voltage. S22. Repeat step S21 to perform superimposed compensation on the driving voltage after the previous superimposed compensation, until the number of repetitions reaches N, and the target driving voltage is obtained; where N is an integer greater than or equal to 2.

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