TW202343419A - Dynamic brightness control method for OLED display panel, OLED display device, and information processing device making changes unnoticed in background brightness when the under-screen fingerprint recognition device is being enabled/disabled - Google Patents

Abstract

The present invention mainly discloses a dynamic brightness control method for an OLED display panel, which is executed by a display driver chip and includes the following steps: determining a digital brightness value (DBV) according to a brightness adjustment command; maintaining the DBV when an under-screen fingerprint recognition device is enabled in a case where the DBV is greater than a first threshold and less than a second threshold; and adjusting the DBV to be the first threshold when the under-screen fingerprint recognition device is enabled in a case where the DBV is less than the first threshold. It is worth noting that when the dynamic brightness control method of the present invention is applied, the display driver chip can realize seamless switching of the background brightness of the OLED display panel, so that users will not notice changes in background brightness when the under-screen fingerprint recognition device is being enabled/disabled.

Description

Dynamic brightness control method of OLED display panel, OLED display device, and information processing device

The present invention relates to the technical field of OLED display devices, and in particular, to a dynamic brightness control method for an OLED display panel.

It is known that organic light-emitting diodes (OLEDs) have the advantages of self-luminous properties, high brightness, high contrast, wide viewing angle, power consumption, high reaction rate, etc., so they have been widely used in self-luminous applications. The production of display panels includes active OLED (i.e., AMOLED) display panels and passive OLED (i.e., PMOLED) display panels. FIG. 1 is a block diagram of a conventional OLED display device. As shown in FIG. 1 , the OLED display device 1a is used in an electronic device (such as a smart phone) and mainly includes an OLED display panel 11a and at least one display driver chip 12a.

It should be understood that the OLED display panel 11a includes M×N OLED elements (ie, sub-pixels) and M×N pixel circuit units used to control the M×N OLED elements to emit light. In the prior art, each of the pixel circuit units is coupled to a scanning signal (i.e., scan) and a light-emitting control signal (i.e., EM). The light-emitting control signal is a PWM signal, so it can be adjusted by adjusting the PWM signal. The duty cycle realizes the brightness control of each of the OLED elements.

See Figure 2, which shows a graph of Digital Brightness Value (DBV) versus PWM duty cycle. According to Figure 2, it can be seen that the existing technology divides the digital brightness value into multiple numerical ranges. Therefore, values 5 to 318 can be defined as interval B, and values 319 to 2047 can be defined as interval A. When the digital brightness value (that is, the user manually adjusts the background display brightness) falls within interval B, the display driver chip 12a realizes brightness control of the OLED element by converting the duty cycle of the PWM signal. Moreover, when the digital brightness value falls within interval A, the duty cycle of the PWM signal is 100%.

On the other hand, a gamma adjustment (correction) unit must be integrated inside the display driver chip 12a. After the display manufacturer completes the gamma correction process, it will set a complex set of gamma setting values in the display driver chip 12a, which is commonly referred to as Gamma binding points in the industry, such as: Gamma 0.45, Gamma 1.8, Gamma 2.0, Gamma 2.2 , Gamma 2.4, Gamma 2.6, etc. In the prior art, the digital brightness value can also be changed correspondingly by changing the gamma setting value (ie, the binding point) to achieve brightness control of the OLED display panel 11a.

However, as under-screen fingerprint recognition devices are widely integrated into mobile electronic devices such as smartphones, the aforementioned prior art adopts the method of adjusting the duty cycle of the PWM signal (ie, the luminescence control signal EM) to achieve There are some flaws in the way the brightness of OLED components is controlled.

For example, when the digital brightness value falls within the interval B, the duty cycle of the PWM signal will be less than 100% as shown in Figure 2, and the display driver chip 12a will correspondingly set a Gamma binding point, such as Gamma 1.8 . At this time, if the under-screen fingerprint recognition device is enabled, the duty cycle of the PWM signal will jump to 100%, but the Gamma binding point will not change accordingly, resulting in changes in the background brightness that can be felt by the human eye.

From the above description, it can be seen that a new dynamic brightness control method for OLED display panels is urgently needed in this field.

The main purpose of the present invention is to provide a dynamic brightness control method for an OLED display panel, which is executed by a display driver chip. When the dynamic brightness control method of the present invention is applied, the display driver chip can realize seamless switching of the background brightness of the OLED display panel, so that the user will not feel any discomfort during the activation/deactivation process of the under-screen fingerprint recognition device. Differential changes in background brightness.

In order to achieve the above object, the present invention proposes a dynamic brightness control method for an OLED display panel, which is executed by a display driver chip and includes the following steps: Determine a digital brightness value (DBV) according to a brightness adjustment command; In the case where the digital brightness value is greater than a first threshold and less than a second threshold, maintaining the digital brightness value with the activation of an under-screen fingerprint recognition device; When the digital brightness value is less than the first threshold, the digital brightness value is adjusted to the first threshold as the under-screen fingerprint recognition device is activated.

In one embodiment, after adjusting the digital brightness value to the first threshold, a data scaling process is further performed on an input display data transmitted by a host computer.

In a possible embodiment, when the display driver chip performs the data scaling process, it searches for the value corresponding to the data scaling parameter from a two-dimensional lookup table including a plurality of the data scaling parameters and a plurality of reference digital brightness values. A reference digital brightness value corresponding to the digital brightness value, thereby obtaining a corresponding data scaling parameter based on the reference digital brightness value, and finally using the data scaling parameter to adjust the input display data to an output display data.

In another possible embodiment, when the display driver chip performs the data scaling process, a data lookup is performed in a two-dimensional lookup table including a plurality of the data scaling parameters and a plurality of reference digital brightness values. operation and an interpolation operation to obtain a data scaling parameter, and finally use the data scaling parameter to adjust the input display data to an output display data.

Moreover, the present invention also provides an OLED display device, which includes at least one display driver chip and an OLED display panel. It is characterized in that the display driver chip executes a dynamic brightness control method of the OLED display panel, thereby forming a fingerprint under one screen. Dynamically adjust the display brightness of the OLED display panel when the recognition device is enabled/disabled; the dynamic brightness control of the OLED display panel includes the following steps: Determine a digital brightness value (DBV) according to a brightness adjustment command; In the case where the digital brightness value is greater than a first threshold and less than a second threshold, maintaining the digital brightness value with the activation of an under-screen fingerprint recognition device; When the digital brightness value is less than the first threshold, the digital brightness value is adjusted to the first threshold as the under-screen fingerprint recognition device is activated.

In one embodiment, after adjusting the digital brightness value to the first threshold, a data scaling process is further performed on an input display data transmitted from a host computer.

In a possible embodiment, when the display driver chip performs the data scaling process, it searches for the value corresponding to the data scaling parameter from a two-dimensional lookup table including a plurality of the data scaling parameters and a plurality of reference digital brightness values. A reference digital brightness value corresponding to the digital brightness value, thereby obtaining a corresponding data scaling parameter based on the reference digital brightness value, and finally using the data scaling parameter to adjust the input display data to an output display data.

In another possible embodiment, when the display driver chip performs the data scaling process, a data lookup is performed in a two-dimensional lookup table including a plurality of the data scaling parameters and a plurality of reference digital brightness values. operation and an interpolation operation to obtain a data scaling parameter, and finally use the data scaling parameter to adjust the input display data to an output display data.

The present invention also provides an information processing device, which has the aforementioned OLED display device. In a feasible embodiment, the information processing device can be a smart phone, a smart watch, a tablet computer, a smart TV, a notebook computer, an all-in-one computer, an access control device, or an electronic door lock.

In order to enable the review committee to further understand the structure, characteristics, purpose, and advantages of the present invention, drawings and detailed descriptions of preferred embodiments are attached below.

Please refer to FIG. 3 , which shows a block diagram of an OLED display device using a dynamic brightness control method for an OLED display panel of the present invention. As shown in FIG. 3 , the OLED display device 1 is used in an electronic device (such as a smart phone) and mainly includes an OLED display panel 11 and at least one display driver chip 12 . To further explain, the OLED display panel 11 includes M×N OLED elements (ie, sub-pixels) and M×N pixel circuit units used to control the M×N OLED elements to emit light. In a conventional design, each pixel circuit unit is coupled to a scanning signal (i.e., scan) and a lighting control signal (i.e., EM). The lighting control signal is a PWM signal, so it can be adjusted by adjusting the PWM signal. The duty cycle realizes the brightness control of each OLED element. See Figure 2 again. In a conventional design, the digital brightness value is divided into multiple numerical ranges. For example, the values 5 to 318 are defined as interval B, and the values 319 to 2047 are defined as interval A.

FIG. 4 shows a flow chart of a dynamic brightness control method for an OLED display panel according to the present invention. As shown in FIGS. 3 and 4 , when the display driver chip 12 performs dynamic brightness control of the OLED display panel of the present invention, step S1 is first performed: determining a digital brightness value (Digital Brightness Value) according to a brightness adjustment command. , DBV). For example, after the user manually adjusts the background brightness of the home screen of his smartphone, the smartphone sends a brightness adjustment command to the display driver chip 12 so that the display driver chip 12 is consistent according to the brightness adjustment command. The background brightness of the OLED display panel 11a is permanently increased/lowered.

Further, the method flow executes step S2: when the digital brightness value is greater than a first threshold and less than a second threshold, maintain the digital brightness with the activation of an under-screen fingerprint recognition device. value. For example, as shown in Figure 2, a value of 318 is defined as the first threshold, and a value of 1600 or 2047 is defined as the first threshold. Therefore, the values 5 to 318 can be further defined as interval B, and the values 319 to 2047 as interval A. When the method of the present invention is applied, as shown in Figure 2, when the DBV (ie, digital brightness value) changes to fall within the interval, the duty cycle of the PWM signal is 100%. Therefore, if the under-screen fingerprint recognition device is enabled at this time, the background brightness will not change significantly. The reason is that when the under-screen fingerprint recognition device is enabled, the display driver chip 12a will adjust the duty cycle of the PWM signal. rise to 100%.

Let me reiterate again, as shown in Figure 2, when the digital brightness value falls within the interval B, the duty cycle of the PWM signal will be less than 100%, and the display driver chip 12a will correspondingly set a Gamma binding point, such as Gamma 1.8. At this time, if the under-screen fingerprint recognition device is enabled, the duty cycle of the PWM signal will jump to 100%, but the Gamma binding point will not change accordingly, resulting in changes in the background brightness that can be felt by the human eye. However, implementing the method of the present invention can solve this problem. In step S3, under the condition that the digital brightness value (i.e., DBV) is less than the first threshold (TH1, for example, 318), the digital brightness is changed as the under-screen fingerprint recognition device is activated. The value is adjusted to the first threshold. Furthermore, if the brightness increases, the display driver chip 12 can further process the application processing by a host computer (such as a smart phone) after adjusting the digital brightness value to the first threshold. A data scaling process is performed on an input display data transmitted from the processor). In this way, when the dynamic brightness control method of the present invention is applied, the display driver chip 12 can realize seamless switching of the background brightness of the OLED display panel 11, allowing the user to enable/disable the under-screen fingerprint recognition device. No differential changes in background brightness will be felt during the process.

FIG. 5 shows a one-dimensional lookup table including a plurality of data scaling parameters and a plurality of reference digital brightness values. It should be supplemented that, as shown in FIG. 5 , when performing the data scaling process, the display driver chip 12 selects from a one-dimensional lookup table including a plurality of data scaling parameters and a plurality of reference digital brightness values. Find a reference digital brightness value corresponding to the digital brightness value, thereby obtain a corresponding data scaling parameter (DS_r1, DS_r2, DS_r3) based on the reference digital brightness value, and finally use the data scaling parameter to adjust the input display data Display data for an output.

Of course, in some cases, the display driver chip 12 cannot directly obtain the data scaling parameters through table lookup. At this time, after completing the data search operation, the display driver chip 12 can further perform an interpolation operation (usually an interpolation operation) to obtain a data scaling parameter, and finally use the data scaling parameter to adjust the input display data to a Output display data.

In this way, the above has completely and clearly explained the dynamic brightness control method of an OLED display panel of the present invention; and, from the above, it can be known that the present invention has the following advantages:

(1) The present invention discloses a dynamic brightness control method for an OLED display panel, which is executed by a display driver chip. When the pixel brightness compensation method of the present invention is applied, the display driver chip can realize seamless switching of the background brightness of the OLED display panel, so that the user will not feel any discomfort during the activation/deactivation process of the under-screen fingerprint recognition device. to differential changes in background brightness.

(2) The present invention also provides an OLED display device, which includes at least one display driver chip and an OLED display panel, and the display driver chip is used to perform the aforementioned dynamic brightness control method of an OLED display panel of the present invention.

(3) The present invention also provides an information processing device, which has the OLED display device of the present invention as described above. Moreover, the information processing device is one selected from the group consisting of smart phones, smart watches, tablet computers, smart TVs, notebook computers, all-in-one computers, access control devices, and electronic door locks. electronic devices.

It must be emphasized that the foregoing disclosed in this case are preferred embodiments. Any partial changes or modifications derived from the technical ideas of this case and easily inferred by those familiar with the art do not deviate from the patent of this case. category of rights.

To sum up, regardless of the purpose, means and effects of this case, it shows that it is completely different from the conventional technology, and that the invention is practical first, and indeed meets the patent requirements for inventions. I sincerely ask the review committee to take a clear look and grant the patent as soon as possible for your benefit. Society is a prayer for the Supreme Being.

1a:OLED display device 11a:OLED display panel 12a: Display driver chip 1:OLED display device 11:OLED display panel 12:Display driver chip S1: Determine a digital brightness value according to a brightness adjustment command; S2: In the case where the digital brightness value is greater than a first threshold and less than a second threshold, maintain the digital brightness value with the activation of an under-screen fingerprint recognition device; S3: When the digital brightness value is less than the first threshold, adjust the digital brightness value to the first threshold as the under-screen fingerprint recognition device is activated.

Figure 1 is a block diagram of a conventional OLED display device; Figure 2 is a graph showing the digital brightness value relative to the PWM duty cycle; Figure 3 is a block diagram of an OLED display device applying a dynamic brightness control method of an OLED display panel according to the present invention; Figure 4 is a flow chart of a dynamic brightness control method for an OLED display panel according to the present invention; and FIG. 5 is a two-dimensional lookup table including a plurality of data scaling parameters and a plurality of reference digital brightness values.

S1: Determine a digital brightness value according to a brightness adjustment command

S2: When the digital brightness value is greater than a first threshold and less than a second threshold, maintain the digital brightness value with the activation of an under-screen fingerprint recognition device.

S3: When the digital brightness value is less than the first threshold, adjust the digital brightness value to the first threshold as the under-screen fingerprint recognition device is activated

Claims (10)

A method for dynamic brightness control of an OLED display panel, which is executed by a display driver chip and includes the following steps: Determine a digital brightness value according to a brightness adjustment command; In the case where the digital brightness value is greater than a first threshold and less than a second threshold, maintaining the digital brightness value with the activation of an under-screen fingerprint recognition device; When the digital brightness value is less than the first threshold, the digital brightness value is adjusted to the first threshold as the under-screen fingerprint recognition device is activated. The dynamic brightness control method of an OLED display panel as described in claim 1, wherein after adjusting the digital brightness value to the first threshold, an input display transmitted by a host computer is further processed. The data undergoes a data scaling process. The dynamic brightness control method of an OLED display panel as described in claim 2, wherein when performing the data scaling process, the display driver chip generates a one-dimensional image including a plurality of the data scaling parameters and a plurality of reference digital brightness values. Find a reference digital brightness value corresponding to the digital brightness value in the lookup table, thereby obtain a corresponding data scaling parameter based on the reference digital brightness value, and finally use the data scaling parameter to adjust the input display data to an output Display data. The dynamic brightness control method of an OLED display panel as described in claim 2, wherein when performing the data scaling process, the display driver chip performs a one-dimensional process including a plurality of the data scaling parameters and a plurality of reference digital brightness values. A data search operation and an interpolation operation are performed in the lookup table to obtain a data scaling parameter, and finally the input display data is adjusted to an output display data using the data scaling parameter. An OLED display device, which includes at least one display driver chip and an OLED display panel, characterized in that the display driver chip executes a dynamic brightness control method of the OLED display panel, thereby enabling/disabling an under-screen fingerprint recognition device. Dynamically adjust the display brightness of the OLED display panel; the dynamic brightness control of the OLED display panel includes the following steps: Determine a digital brightness value according to a brightness adjustment command; In the case where the digital brightness value is greater than a first threshold and less than a second threshold, maintaining the digital brightness value with the activation of an under-screen fingerprint recognition device; When the digital brightness value is less than the first threshold, the digital brightness value is adjusted to the first threshold as the under-screen fingerprint recognition device is activated. The OLED display device of claim 5, wherein after adjusting the digital brightness value to the first threshold, a data scaling process is further performed on an input display data transmitted by a host computer. The OLED display device of claim 5, wherein when performing the data scaling process, the display driver chip searches from a two-dimensional lookup table including a plurality of the data scaling parameters and a plurality of reference digital brightness values. A reference digital brightness value corresponding to the digital brightness value is obtained, thereby obtaining a corresponding data scaling parameter based on the reference digital brightness value, and finally using the data scaling parameter to adjust the input display data to an output display data. The OLED display device of claim 5, wherein when performing the data scaling process, the display driver chip executes in a two-dimensional lookup table including a plurality of the data scaling parameters and a plurality of reference digital brightness values. A data search operation and an interpolation operation are performed to obtain a data scaling parameter, and finally the input display data is adjusted to an output display data using the data scaling parameter. An information processing device, characterized by having an OLED display device as described in any one of claims 5 to 8. The information processing device as described in claim 9 is a group consisting of a smart phone, a smart watch, a tablet computer, a smart TV, a notebook computer, an all-in-one computer, an access control device, and an electronic door lock. An electronic device of choice.

Images