CN111986610B

CN111986610B - Multi-screen display unit color correction synchronization method

Info

Publication number: CN111986610B
Application number: CN202010906415.0A
Authority: CN
Inventors: 赖炳旭
Original assignee: Ziminsheng Photoelectric Technology Suzhou Co ltd
Current assignee: Ziminsheng Photoelectric Technology Suzhou Co ltd
Priority date: 2020-09-01
Filing date: 2020-09-01
Publication date: 2022-12-27
Anticipated expiration: 2040-09-01
Also published as: CN111986610A

Abstract

A multi-screen display unit color correction synchronization method is used for carrying out picture synchronization and color correction on at least two display units. First, providing respective synchronous reference signals of at least two display units. Then, the phases of the synchronous reference signals are compared, and if the difference value of the phases exceeds a set range, the intermediate value or intermediate approximate value of the difference value is obtained. Then, the intermediate value or the intermediate approximate value is compensated to the respective synchronous reference signals of at least two display units. And reading the respective reference voltage and Gamma voltage register values of the at least two display units. And calculating the average value of the register values of the reference voltage and the Gamma voltage of at least two display units. Then, the average values of the register values of the reference voltage and the Gamma voltage are compensated and adjusted. And respectively writing the register values of the compensated and adjusted reference voltage and the Gamma voltage into at least two display units.

Description

Multi-screen display unit color correction synchronization method

Technical Field

The present invention relates to a color correction synchronization method for multi-screen display units, and more particularly, to a color correction synchronization method for multi-screen display units in a 3D imaging system.

Background

In the current display unit technology, for example, large-sized monitors and televisions, the voltages of the driving chips of the display module are uniformly provided by the power converters in the module, so the voltages referenced by the plurality of driving chips in such large-sized modules are all the same, and thus the colors of the voltages output to the panel circuit by the respective driving chips in the same gray scale are also the same. However, in the small and medium-sized modules composed of a single driving chip, because the reference voltages generated in the respective modules are not consistent, when two respective modules are assembled in the same 3D application system, the same gray scale pattern may present inconsistent color images due to slight voltage differences.

In order to adjust the situation of color inconsistency caused by voltage difference, optical instruments are adopted to correct the colors of individual modules during system assembly, so that the displayed image does not generate color difference. However, it is inefficient to slow the entire production process because of the calibration procedure introduced in the optical instrument. In view of the above, in the technical field of 3D application systems, it is one of the problems to be actively solved by those skilled in the art how to perform frame synchronization and color correction on a plurality of display units so that the same gray-scale pattern can present a consistent color image.

Disclosure of Invention

The present invention provides a method for synchronizing color correction of multiple display units, which comprises first performing synchronization between two display units, and then comparing and adjusting register values of reference voltage and Gamma voltage of the two display units to make the colors of the two display units closer to or even the same.

To achieve at least one of the above advantages or other advantages, an embodiment of the present invention provides a color calibration synchronization method for multi-screen display units, which is used for performing frame synchronization and color calibration on at least two display units. The multi-screen display unit color correction synchronization method comprises the following steps:

providing respective synchronous reference signals of the at least two display units;

comparing the phases of the synchronous reference signals of the at least two display units, and if the difference value of the phases exceeds a set range, taking the middle value or the middle approximate value of the difference value;

respectively compensating the intermediate value or the intermediate approximate value to the synchronous reference signals of the at least two display units;

reading the respective reference voltage of the at least two display units and the register value of the Gamma voltage;

calculating the average value of the register values of the reference voltage and the Gamma voltage of the at least two display units;

sixthly, respectively carrying out compensation adjustment on the reference voltage and the average value of the register value of the Gamma voltage; and

and seventhly, respectively writing the register values of the compensated and adjusted reference voltage and the Gamma voltage into the at least two display units.

In an embodiment, before the fourth step, the method further includes the following step of repeating the first to third steps until the phases of the synchronous reference signals of the at least two display units respectively match or the phase difference value is within the set range.

In one embodiment, the synchronization reference Signal is a TE Signal (Tearing Effect Signal) or a virtual vertical synchronization Signal (Vsync) of each of the at least two display units.

In one embodiment, the step is reading the synchronous reference signals of the other party through the at least two display units respectively.

In one embodiment, the second step is comparing the phases of the synchronous reference signals by phase comparators inside the at least two display units.

In an embodiment, the fourth step is to read the register values of the reference voltage and the Gamma voltage stored in the register of the other side through the at least two display units respectively.

In an embodiment, the compensation adjustment performed in the sixth step is to increase or decrease the compensation value of the average value of the register values of the reference voltage and the Gamma voltage through the at least two display units.

In an embodiment, the seventh step is to write the register values of the compensated and adjusted reference voltage and the Gamma voltage into respective registers through the at least two display units.

In an embodiment, the method for color correction synchronization of multi-screen display units further includes a step eight of performing dither processing (dither) on the reference voltage and the Gamma voltage through each of the at least two display units.

In one embodiment, the dithering process is performed to dither driving voltages of frames (frames) before and after the at least two display units, wherein the at least two display units include a first display unit and a second display unit, according to one of the following modes:

in the first mode, the driving voltage of the previous frame is obtained by adding a unit value to the average value of the Gamma voltage, and the driving voltage of the next frame is obtained by subtracting a unit value from the average value of the Gamma voltage;

in a second mode, the driving voltage of the previous frame is the average of the sum of the Gamma voltage of the first display unit and the average value of the Gamma voltage, and the driving voltage of the next frame is the average of the sum of the Gamma voltage of the second display unit and the average value of the Gamma voltage; and

in a third mode, the driving voltage of the previous frame is the Gamma voltage of the first display unit, and the driving voltage of the next frame is the Gamma voltage of the second display unit.

Therefore, the multi-screen display unit color correction synchronization method provided by the invention can be used for synchronizing different display units by comparing and adjusting the phases of synchronous reference signals (such as TE signals) of the different display units, then reading the difference of analog voltages generated between two display screen modules, reading the register values of the reference voltage and the Gamma voltage set in the second display unit by using auxiliary signals set in the first display unit, calculating the average value of the register values of the reference voltage and the Gamma voltage set in the first display unit, and storing the average value back to the originally set register value after calculating the set increment and decrement value to generate similar analog voltages, so that the colors displayed by the two display screens are closer to or even the same. The method and the system disclosed by the invention can provide a quick correction process, greatly reduce the investment cost of production and improve the efficiency of a module correction procedure.

The foregoing description is only an overview of the technical solutions of the present invention, and in order to make the technical means of the present invention more clearly understood, the present invention may be implemented in accordance with the content of the description, and in order to make the above and other objects, features, and advantages of the present invention more clearly understood, the following preferred embodiments are described below in detail with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are included to provide a further understanding of the embodiments of the application, are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the principles of the application. It should be apparent that the drawings in the following description are only examples of the present application and are not intended to limit the embodiments of the present invention, and that other drawings may be derived from the drawings by those skilled in the art without inventive faculty. The drawings comprise:

FIG. 1 is a flowchart illustrating a method for color correction synchronization of multi-screen display units according to the present invention;

FIG. 2 is a block diagram of the at least two display units according to an embodiment of the present invention;

FIG. 3 is a flowchart illustrating a procedure for reading register values such as reference voltage and Gamma voltage according to an embodiment of the present invention; and

FIG. 4 is a flowchart illustrating a color correction synchronization method for multi-screen display units according to an embodiment of the present invention.

The attached drawings are marked as follows: 1-first display unit 10-first controller 100-first decoder 11-first phase comparator 12-first register 2-second display unit 20-second controller 200-second decoder 21-second phase comparator 22-second register

Detailed Description

Specific structural and functional details disclosed herein are merely representative and are provided for purposes of describing example embodiments of the present invention. The present invention may, however, be embodied in many alternate forms and should not be construed as limited to only the embodiments set forth herein.

Referring to FIG. 1, FIG. 1 is a flowchart illustrating a method for color correction synchronization of multi-screen display units according to the present invention. In an embodiment, the present invention provides a color correction synchronization method for multi-screen display units, which is used for performing frame synchronization and color correction on at least two display units, and comprises the following steps:

step one (S01) is to provide respective synchronous reference signals of the at least two display units.

Step two (S02), comparing the phases of the synchronous reference signals of the at least two display units, and if the difference value of the phases exceeds a set range, taking the middle value or the middle approximate value of the difference value.

And step three (S03) of respectively compensating the intermediate value or the intermediate approximate value to the synchronous reference signals of the at least two display units.

And step four (S04) of reading the respective reference voltages and Gamma voltage register values of the at least two display units.

And step five (S05) of calculating the average value of the reference voltage and the Gamma voltage register value of the at least two display units.

And step six (S06), respectively compensating and adjusting the average value of the reference voltage and the Gamma voltage register value.

And a seventh step (S07) of writing the register values of the reference voltage and the Gamma voltage after compensation adjustment into the at least two display units respectively.

In one embodiment, before performing the step four (S04), the method for color calibration synchronization of multi-panel display units further includes a step (S035) of repeating the step one (S01) to the step three (S03) until the phases of the synchronization reference signals of the at least two display units match or the phase difference value is within the predetermined range.

In one embodiment, the synchronization reference Signal is a TE Signal (Tearing Effect Signal) or a virtual vertical synchronization Signal (Vsync) of each of the at least two display units. Specifically, the TE signal is a TE signal specified in the MIPI protocol (MIPI), the Mobile Industry Processor Interface (CPU), the pivot . In addition to using the TE signal as the synchronization reference signal, a self-configured signal inside the driving chip, such as the virtual vertical synchronization signal (Vsync), can be used to perform the synchronization of the same procedure.

In one embodiment, the step one (S01) reads the synchronous reference signals of the other party through the at least two display units, respectively.

Referring to fig. 2, fig. 2 is a block diagram of at least two display units according to an embodiment of the present invention, for showing a connection relationship between the two display units. The at least two display units include a first display unit 1 and a second display unit 2, and in one embodiment, may be formed of Micro organic light emitting display units (Micro OLEDs). As shown in fig. 2, the first display unit 1 and the second display unit 2 respectively have a first controller 10 and a second controller 20, and the first controller 10 and the second controller 20 respectively have a first decoder 100 and a second decoder 200. The first decoder 100 and the second decoder 200 can be connected via respective pins to transmit or read various related or required information such as the above-mentioned synchronous reference signal via respective auxiliary signals.

In one embodiment, the second step (S02) compares the phases of the synchronous reference signals by phase comparators inside the at least two display units, respectively. As shown in fig. 2, the first display unit 1 and the second display unit 2 have a first phase comparator 11 and a second phase comparator 21, respectively. When the first display unit and the second display unit provide the respective generated TE signals, the phase comparison can be performed by the first phase comparator 11 and the second phase comparator 21 inside.

In an embodiment, the step four (S04) reads the register values of the reference voltage and the Gamma voltage stored in the register of the other party through the at least two display units, respectively. As shown in fig. 2, the first display unit 1 and the second display unit 2 respectively have a first register 12 and a second register 22 for storing the related register values. After the first display unit 1 and the second display unit 2 have been synchronized, the register value can be read by using the auxiliary signal. The first display unit 1 is connected to the second display unit 2 through the auxiliary signal to read register values such as the reference voltage and the Gamma voltage in the second display unit 2, and the same second display unit 2 can also be connected to the first display unit 1 through the auxiliary signal to read corresponding register values in the same way. After the reading of each display unit is finished, the existing register values of reference voltage, gamma voltage and the like and the read register value of the other display unit are calculated to be an average value.

Referring to fig. 3, fig. 3 shows a reading procedure of register values such as reference voltage and Gamma voltage. Firstly, the first display unit 1 sends out 1bit (bit) "0" read after sending out the Start code (Start code) "A5" by the auxiliary signal, then sends out blank 1bit "0", then sends out the register Address (Address), and continuously read bit group number (Byte count), then continues 1bit "0" to wait for the second display unit 2 to reply the acknowledgement, at this time, the auxiliary signal main control right is switched to the second display unit 2, the second display unit waits for 1bit "0" after replying ACK 1bit "1", then sends out continuous register value (Data), until continuous 1bit "0" is continued after the transmission of the number of Data bit groups is completed, the main control right is switched to the first display unit 1 again, and the first display unit 1 sends out the end code (stop code) "5A". At this time, a read process is completed.

Please refer to the table one below, which shows the register Address (Address) of the register value such as Gamma voltage and the Description (Description) of the register value. In this embodiment, the associated register values of Gamma voltage include the Top level (Top Gamma) and the bottom level (Button Gamma) of the internal Gamma voltage of the driver chip, and 8 Gamma voltages (Gamma 1 to Gamma 8) between them.

Address	Description
		0xB0	top Gamma
0xB1	Gamma1
		0xB2	Gamma2
0xB3	Gamma3
		0xB4	Gamma4
0xB5	Gamma5
		0xB6	Gamma6
0xB7	Gamma7
		0xB8	Gamma8
0xB9	BOT Gamma

Watch 1

In an embodiment, the compensation adjustment performed in the sixth step (S06) is to increase or decrease the compensation value of the average value of the reference voltage and the Gamma voltage through the at least two display units.

Referring to table two below, table two shows the compensation adjustment result for the average value of the register values of the reference voltage and the Gamma voltage in one embodiment. The Compensation adjusted reference voltage and the Gamma voltage register Value can be the result of increasing or decreasing an Compensation Value (Compensation) from the Average Value (Average Value) corresponding to different Bit values (Bit). For example, compensation values Compensation (1), compensation (2), and Compensation (3) may represent 1 to 3 unit values, respectively. When the default value (default) of the average value is set to 0, the register values after compensation adjustment may include +3, +2, +1, -2, -3, according to the difference of increasing and decreasing compensation values. It should be noted that the bit value "7" in the second table corresponds to the dithering (heat function), i.e. besides the color displayed by the two display units tends to be consistent by the compensation adjustment, the present invention further utilizes the dithering to improve the color correction effect.

Bit	Description
			3	Average Vaue+Compensation(3)	+3
2	Average Vaue+Compensation(2)	+2
			1	Average Vaue+Compensation(1)	+1
0	Average Vaue(default)	0
			4	Average Vaue-Compensation(1)	-1
5	Average Vaue-Compensation(2)	-2
			6	Average Vaue-Compensation(3)	-3
7	Dither function

Watch two

In an embodiment, the step seven (S07) is to write the register values of the compensation adjusted reference voltage and the Gamma voltage into respective registers through the at least two display units. Referring to fig. 2, that is, after the first display unit 1 and the second display unit 2 complete the compensation adjustment of the average value, the register values of the relevant reference voltage and the Gamma voltage can be written into the first register 12 and the second register 22, respectively.

In one embodiment, the method for color correction synchronization of multiple display units further includes a step eight (S08) of performing a dithering (dither function) on the reference voltage and the Gamma voltage respectively through the at least two display units. As described above, although the present invention calculates the average value of the reference voltages of the two display units and the Gamma voltage and compensates and adjusts the average value, so as to make the colors displayed by the two display units as consistent as possible, if the color correction effect is still not as expected, the present invention further utilizes the dithering process to improve the color correction effect.

In one embodiment, the dithering process is performed by dithering the driving voltages of a frame (frame) before and a frame (frame) after the frame of the at least two display units according to different setting modes.

Please refer to the following Table three, which shows the Description (Description) of the optional dithering mode corresponding to different Bit values (bits).

Watch III

As shown in table three, the selectable dither processing modes include:

in the Mode one (Mode 1), as the Mode corresponding to the Bit (Bit) value 00 in the table three, the driving voltage of the previous frame is the Average value of the Gamma voltage plus one unit value (Average + 1), and the driving voltage of the next frame is the Average value of the Gamma voltage minus one unit value (Average-1).

Mode two (Mode 2) as shown in Table three corresponding to Bit (Bit) value 01, the driving voltage of the previous frame is an average [ (1 'st Gamma + Avg)/2 ] of the sum of the Gamma voltage of the first display unit and the average value of the Gamma voltage, and the driving voltage of the subsequent frame is an average [ (2' nd Gamma + Avg)/2 ] of the sum of the Gamma voltage of the second display unit and the average value of the Gamma voltage.

Mode three (Mode 3) in the Mode corresponding to Bit (Bit) value 10 in table three, the driving voltage of the previous frame is the Gamma voltage (1 'st Gamma) of the first display unit, and the driving voltage of the subsequent frame is the Gamma voltage (2' nd Gamma) of the second display unit.

In addition to selecting the different modes, the dithering process may also select to maintain the initial dithering setting of the display unit or maintain the selected mode for dithering, such as the unchanged (No change) condition represented by the Bit (Bit) value 11 in table three, according to the actual requirement.

Referring to FIG. 4, FIG. 4 is a flowchart illustrating a method for color correction synchronization of multi-screen display units according to an embodiment of the present invention. In combination with the above-described components and related steps, the method for synchronizing color correction of multi-screen display units includes the following steps:

step S11, the image transmission unit transmits the video data to the first display unit and the second display unit.

Step S12, the first display unit receives the video data of the image transmission unit.

And S13, whether entering a TE transmission mode.

Step S14, if the selection in step S13 is yes, enter into the TE signal synchronization alignment procedure. If step S13 selects no, the process proceeds directly to step S19 described below.

In step S15, the first controller switches the TE signal to the auxiliary signal and receives the TE signal of the second display unit.

Step S16, determine whether the TE signals of the first display unit and the second display unit are in phase.

Step S17, phase match?

Step S18, if the phase is not matched, the phase of the TE signal of the first display unit is adjusted, and step S16 is executed again.

Step S19, if the phases are consistent, the first display unit reads the reference voltage and the Gamma voltage register value of the second display unit.

And step S20, judging whether the register values are the same.

Step S21, if the register values are the same, the register values of the reference voltage and the Gamma voltage are increased or decreased through external adjustment. This step is an optional step, i.e. it can be determined whether to further adjust the register value by external tools according to whether the color correction results of the first display unit and the second display unit are in expectation.

In step S22, the color synchronization process is completed.

And S23, if the register values are different in the step S20, calculating the average value of the register values of the first display unit and the second display unit.

And step S24, reading the set increasing and decreasing values of the increasing and decreasing registers.

And S25, compensating the average value of the increasing and decreasing values and storing the average value back to the register values of the reference voltage and the Gamma voltage.

Step S26, whether the color representation is the same.

Step S27, if the colors are different, the setting increasing and decreasing value of the increasing and decreasing register can be set from the outside. As mentioned above, whether to further adjust the register value through an external tool can be determined according to whether the color correction results of the first display unit and the second display unit are in expectation. After the external adjustment is completed, step S24 is executed again.

In step S28, if the colors are the same, the color synchronization process is completed.

In summary, since the reference voltages generated by the different display units are slightly different, when the different display units display a picture together, the difference in color is visually generated, which affects the user's appearance. Therefore, the scheme firstly compares and adjusts the phase of synchronous reference signals (such as TE signals) of different display units to enable the different display units to complete synchronization, then utilizes the difference of analog voltages generated between two display screen modules, utilizes an auxiliary signal arranged in a first display unit to read the register values of the reference voltage and the Gamma voltage arranged in a second display unit, calculates the average value with the existing register values of the reference voltage and the Gamma voltage of the first display unit, and restores the average value to the originally set register value after the set increment and decrement value is calculated to generate similar analog voltages, so that the colors displayed by the two display screens are closer to or even the same. The method and the system disclosed by the invention can provide a quick synchronous correction process, greatly reduce the investment cost of production and improve the efficiency of a module correction procedure.

Although the present invention has been described with reference to a preferred embodiment, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A multi-screen display unit color correction synchronization method is used for performing picture synchronization and color correction on at least two display units, and is characterized in that the multi-screen display unit color correction synchronization method comprises the following steps:

2. A multi-display unit color correction synchronization method as recited in claim 1, further comprising, before the step four, the step of repeating the steps one through three until the phases of the synchronization reference signals of the at least two display units match or the phase difference is within the predetermined range.

3. A multi-display unit color correction synchronization method as claimed in claim 1, wherein the synchronization reference Signal is a TE Signal (Tearing Effect Signal) or a virtual vertical synchronization Signal (Vsync) of each of the at least two display units.

4. A multi-display unit color correction synchronization method as claimed in claim 1, wherein the step of reading the synchronization reference signals of each other through the at least two display units respectively.

5. A multi-display unit color correction synchronization method as recited in claim 1, wherein the second step is comparing the phases of the synchronization reference signals by phase comparators inside the at least two display units.

6. A multi-display unit color correction synchronization method as recited in claim 1, wherein the fourth step is to read the register values of the reference voltage and the Gamma voltage stored in the register of the other side by the at least two display units respectively.

7. A multi-display unit color correction synchronization method as claimed in claim 1, wherein the compensation adjustment performed in the sixth step is an increase or decrease of the compensation value by the at least two display units respectively for the average value of the register values of the reference voltage and the Gamma voltage.

8. A multi-display unit color correction synchronization method as claimed in claim 1, wherein the seventh step is to write the register values of the compensation adjusted reference voltage and Gamma voltage into respective registers through the at least two display units.

9. A multi-screen display unit color correction synchronization method as recited in claim 1, wherein the multi-screen display unit color correction synchronization method further comprises:

and step eight, performing jitter processing (diter) on the reference voltage and the Gamma voltage through the at least two display units respectively.

10. A multi-display unit color correction synchronization method as claimed in claim 9, wherein the dithering process is performed to dither the driving voltages of a frame preceding (frame) frame and a frame succeeding frame of the at least two display units according to one of the following modes, wherein the at least two display units comprise a first display unit and a second display unit, and the modes comprise: