Projection display device and white balance adjustment method

Abstract

This application discloses a projection display device and a white balance adjustment method, belonging to the field of projection technology. The projection display device includes a processor configured to: drive a primary color light source to emit primary color light; obtain a first chromaticity coordinate value of white light generated by mixing the primary color light; and, if the deviation between the first chromaticity coordinate value and a standard chromaticity coordinate value is greater than a deviation threshold, adjust the emission parameters of the primary color light source based on the standard chromaticity coordinate value, so that the deviation between the chromaticity coordinate value of the white light generated by mixing the primary color light emitted by the adjusted primary color light source and the standard chromaticity coordinate value is less than or equal to the deviation threshold, wherein the standard chromaticity coordinate value is the white light chromaticity coordinate that the projection display device expects to achieve. Thus, through precise color control and correction, the projection display device can reduce color distortion and deviation, improve image clarity and contrast, and thereby improve display stability and consistency.

Description

Projection display device and white balance adjustment method

[0001] This application claims priority to Chinese patent application No. 202311553434.X filed on November 20, 2023, with invention name “White balance adjustment method, device, laser projection equipment and storage medium”, and Chinese patent application No. 202410182350.8 filed on February 18, 2024, with invention name “Projection display device, white balance adjustment method and white balance adjustment system”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of projection technology, and in particular to a projection display device and a white balance adjustment method. Background Art

[0003] The white balance of a projection display device is a key indicator that describes the accuracy of the mixture of the three primary colors (red, green, and blue) used to create white. It determines the device's ability to accurately reproduce original colors. However, the white balance of a projection display device is easily affected by lighting conditions such as the light source, optical path, and lighting efficiency, resulting in color casts and imbalanced white balance. Therefore, white balance adjustments are required before and during production to ensure accurate color reproduction. Summary of the Invention

[0004] This application provides a projection display device and a white balance adjustment method, which can adjust the white balance of the projection display device to ensure the projection effect of the projection display device. The technical solution is as follows:

[0005] In a first aspect, a projection display device is provided, the projection display device comprising:

[0006] A primary color light source, used for emitting primary color light;

[0007] a digital micromirror device, located on the light-emitting side of the primary color light source, for modulating the primary color light and reflecting the modulated light to the projection lens;

[0008] The projection lens is used to image the light beam emitted by the digital micromirror device;

[0009] A processor connected to the digital micromirror device, configured to:

[0010] driving the primary color light sources to emit primary color lights, and obtaining first color coordinate values ​​of white light generated by mixing the primary color lights;

[0011] When the deviation between the first color coordinate value and the standard color coordinate value is greater than a deviation threshold, the light-emitting parameters of the primary color light sources are adjusted based on the standard color coordinate value so that the deviation between the color coordinate value of the white light generated by the mixture of the primary color lights emitted by the adjusted primary color light sources and the standard color coordinate value is less than or equal to the deviation threshold, and the standard color coordinate value is the white light color coordinate that the projection display device expects to achieve.

[0012] In a second aspect, a white balance adjustment method is provided, which is applied to a projection display device, and the method includes:

[0013] driving the primary color light sources to emit primary color lights, and obtaining first color coordinate values ​​of white light generated by mixing the primary color lights;

[0014] When the deviation between the first color coordinate value and the standard color coordinate value is greater than a deviation threshold, the light-emitting parameters of the primary color light sources are adjusted based on the standard color coordinate value so that the deviation between the color coordinate value of the white light generated by the mixture of the primary color lights emitted by the adjusted primary color light sources and the standard color coordinate value is less than or equal to the deviation threshold, and the standard color coordinate value is the white light color coordinate that the projection display device expects to achieve.

[0015] In a third aspect, a white balance adjustment system is provided, comprising: a main control device, an illuminometer, and the projection display device described in the first aspect, wherein the main control device is connected to the projection display device and the illuminometer respectively;

[0016] The main control device is used to control the projection display device to enter a white balance debugging mode so that the projection display device projects multiple test images in chronological order; control the illuminance meter to collect color coordinate values ​​corresponding to the test images, and determine the target current duty cycle corresponding to multiple primary colors constituting the pixel color based on the white balance algorithm and the color coordinate values, and send the target current duty cycle to the projection display device.

[0017] In a fourth aspect, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores at least one instruction, at least one program, a code set, or an instruction set, and the at least one instruction, the at least one program, the code set, or the instruction set is loaded and executed by a processor to implement the white balance adjustment method provided in the second aspect above.

[0018] In a fifth aspect, a computer program product is provided, wherein the computer program product includes program instructions, and when the program instructions are executed by a processor, the white balance adjustment method provided in the second aspect is implemented.

[0019] As can be seen from the above technical solutions, the projection display device and white balance adjustment method provided by this application monitor and provide feedback on the current state of white light color coordinates through a processor. When it detects that the deviation between a first color coordinate value and a preset standard color coordinate value is greater than a deviation threshold, the white balance adjustment process is initiated. Based on the standard color coordinate values, the processor adjusts the emission parameters of the primary color light source to gradually reduce the deviation in the color coordinate values. Through this automatic correction mechanism, the projection display device can ensure that it consistently outputs white light that meets the desired color standard under different operating environments and conditions. In this way, through precise color control and correction, the projection display device can reduce color distortion and deviation, improve image clarity and contrast, and thereby enhance display stability and consistency. In addition, because the device can automatically adapt to environmental changes and adjust color parameters, the user does not need to manually perform complex color settings and adjustments, thereby simplifying the operation process and improving ease of use. Moreover, by automatically adjusting the emission parameters, aging or damage of the light source caused by prolonged operation in non-standard color conditions can be avoided, which to a certain extent also helps to extend the service life of the projection display device. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0021] FIG1 is a schematic structural diagram of a projection display device provided in an embodiment of the present application;

[0022] FIG2 is a hardware configuration block diagram of a projection display device provided in an embodiment of the present application;

[0023] FIG3 is a schematic diagram of the internal structure of a laser projection device provided in an embodiment of the present application;

[0024] FIG4 is a schematic diagram of software configuration of a projection display device provided in an embodiment of the present application;

[0025] FIG5 is a schematic diagram of an application scenario provided by an embodiment of the present application;

[0026] FIG6 is a schematic diagram of an optical path architecture of a laser projection device provided in an embodiment of the present application;

[0027] FIG7 is a schematic diagram of color coordinate values ​​provided in an embodiment of the present application;

[0028] FIG8 is a schematic diagram of a fluorescent wheel structure provided in an embodiment of the present application;

[0029] FIG9 is a schematic diagram of a color gamut plane provided in an embodiment of the present application;

[0030] FIG10 is a schematic structural diagram of another projection display device provided in an embodiment of the present application;

[0031] FIG11 is a schematic flow chart of a white balance adjustment method provided in an embodiment of the present application;

[0032] FIG12 is a schematic diagram of the architecture of a white balance adjustment system provided in an embodiment of the present application;

[0033] FIG13 is a schematic diagram of the hardware structure of a main control device and a projection display device provided in an embodiment of the present application;

[0034] FIG14 is a schematic flow chart of another white balance adjustment method provided in an embodiment of the present application;

[0035] FIG15 is a schematic flow chart of another white balance adjustment method provided in an embodiment of the present application;

[0036] FIG16 is a schematic structural diagram of a white balance adjustment device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0037] In order to make the purpose and implementation of this application clearer, the exemplary implementation of this application will be clearly and completely described below in conjunction with the drawings in the exemplary embodiments of this application. Obviously, the described exemplary embodiments are only part of the embodiments of this application, not all of the embodiments.

[0038] It should be noted that the brief descriptions of terms in this application are only for the purpose of facilitating the understanding of the embodiments described below, and are not intended to limit the embodiments of this application. Unless otherwise specified, these terms should be understood according to their ordinary and usual meanings.

[0039] In the specification and claims of this application and the accompanying drawings, the terms "first," "second," "third," etc. are used to distinguish similar or similar objects or entities, and are not necessarily intended to limit a particular order or sequence, unless otherwise noted. It should be understood that the terms used in this manner are interchangeable under appropriate circumstances.

[0040] The terms "comprise," "include," and "have," and any variations thereof, are intended to cover but not exclude inclusion; for example, a product or device comprising a list of components is not necessarily limited to all the components expressly listed but may include other components not expressly listed or inherent to such product or device.

[0041] Before introducing the white balance adjustment method provided in the embodiment of the present application, the projection display device, application background and implementation environment to which the technical solution of the embodiment of the present application is applicable are first introduced.

[0042] First, the structure of the projection display device to which the technical solution of the embodiment of the present application is applicable is introduced.

[0043] The projection display device provided in the embodiments of the present application can have various implementation forms, for example, a projection device, a laser projection device, a television, a monitor, a laser television, etc.

[0044] In some embodiments, FIG1 is a schematic diagram of the structure of a projection display device provided in an embodiment of the present application. As shown in FIG1 , the projection display device includes a processor 101, a memory 102, and a computer program stored in the memory 102 and executable by the processor 101. When executed by the processor 101, the computer program implements the white balance adjustment method provided in an embodiment of the present application.

[0045] The processor 101 may be a CPU (Central Processing Unit), or other general-purpose processors, a DSP (Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), etc. The general-purpose processor may be a microprocessor or any conventional processor.

[0046] The memory 102 may include a high-speed RAM (Random Access Memory), a ROM (Read-Only Memory), or an NVM (Non-Volatile Memory), such as at least one disk storage.

[0047] In some embodiments, the projection display device further includes a bus (not shown in the figure), and the processor 101 and the memory 102 can be connected via the bus.

[0048] The bus may be an ISA (Industry Standard Architecture) bus, a PCI (Peripheral Component Interconnect) bus, or an EISA (Extended Industry Standard Architecture) bus. Specifically, the bus may be divided into an address bus, a data bus, a control bus, etc. It should be understood that the aforementioned buses are not limited to only one bus or one type of bus.

[0049] In some embodiments, Figure 2 is a hardware configuration block diagram of the projection display device provided in an embodiment of the present application, and the projection display device includes: a tuner and demodulator 210, a communicator 220, a detector 230, an external device interface 240, a controller 250, a display 260, an audio output interface 270, as well as a memory, a power supply, etc.

[0050] The tuner / demodulator 210 receives broadcast television signals via wired or wireless reception and demodulates audio and video signals, such as EPG (Electronic Program Guide) data signals, from multiple wireless or wired broadcast television signals. The detector 230 is used to collect signals from the external environment or external interactions and may include a sound collector and an image collector. The controller 250 includes a central processing unit, a video processor, an audio processor, a graphics processor, RAM, ROM, and first to nth interfaces for input / output. The display 260 may be a laser projector, or a projection device and projection screen.

[0051] In a possible implementation, the controller 250 and the tuner / demodulator 210 may be located in different separate devices, that is, the tuner / demodulator 210 may also be located in an external device of the main device where the controller 250 is located, such as an external set-top box.

[0052] In one possible implementation, the controller 250 controls the operation of the projection display device and responds to user operations through various software control programs stored in the memory. In other words, the controller 250 controls the overall operation of the projection display device.

[0053] In one possible implementation, a user may input a user command through a GUI (Graphical User Interface) displayed on the display 260, and the user input interface receives the user input command through the GUI. Alternatively, a user may input a user command by inputting a specific sound or gesture, and the user input interface may receive the user input command by recognizing the sound or gesture through a sensor. In addition, an output interface (e.g., the display 260 and / or the audio output interface 270) is configured to output user interaction information. The communicator 220 is used to communicate with a terminal, a server, or other devices.

[0054] Taking a laser projection device as an example, FIG3 is a schematic diagram of the internal structure of a laser projection device provided in an embodiment of the present application. As shown in FIG3, after the upper shell of the laser projection device is disassembled, its internal structure can be divided into: a light source 301, an optical machine 302, and a lens 303 according to its optical function. Among them, the light source 301 is used to provide a light source illumination beam, which is transmitted to the rear-end light valve modulation device and the lens 303. The light source 301 may include a monochromatic laser of at least one color, such as a blue laser; it may also include a two-color laser, such as a blue laser and a red laser; it may also be a three-color laser light source, that is, a laser including three colors of red, green, and blue, for providing a three-color laser illumination beam.

[0055] In practical applications, the laser beam provided by light source 301 undergoes light combining and shaping before entering the illumination optical path of optical engine 302. In the DLP (Digital Light Processing) projection architecture, the DMD (Digital Micromirror Device) chip is the core light valve modulation device. The DMD chip receives a drive control signal corresponding to the image signal and flips the thousands of tiny mirrors on its surface to the positive or negative angle corresponding to the drive signal, reflecting the light beam from its surface into lens 303. Lens 303 can be an ultra-short-throw projection lens, which is used to project the image beam onto the projection screen, thereby displaying the projected image.

[0056] As an example, the laser projection display device in the above example may be an ultra-short-throw laser projection device.

[0057] In some embodiments, Figure 4 is a software configuration diagram of the projection display device provided in an embodiment of the present application. As shown in Figure 4, the system is divided into four layers, from top to bottom, namely, the application layer (referred to as "application layer"), the application framework layer (referred to as "framework layer"), the Android runtime (Android runtime) and the system library layer (referred to as "system runtime library layer"), and the kernel layer.

[0058] Among them, the kernel layer includes at least one of the following drivers: audio driver, display driver, Bluetooth driver, camera driver, WIFI (Wireless Fidelity) driver, USB (Universal Serial Bus) driver, HDMI (High Definition Multimedia Interface) driver, sensor driver (such as fingerprint sensor, temperature sensor, pressure sensor, etc.), and power driver, etc.

[0059] After introducing the structure of the projection display device to which the technical solution of the embodiment of the present application is applicable through the above-mentioned Figures 1 to 4, the application scenarios of the embodiment of the present application will be introduced next.

[0060] 5 , which is a schematic diagram of a scenario in some embodiments provided by the present application, including a projection display device 100, a control device 200, a smart device 300, and a server 400. A user can operate the projection display device 200 through the smart device 300 or the control device 200 to play multimedia resources such as audio and video on the projection display device 200.

[0061] The projection display device 100 may have any of the structures shown in FIG. 1 to FIG. 4 , and the embodiment of the present application does not impose any limitation thereto.

[0062] In one possible implementation, the control device 200 may be a remote controller. Communication between the remote controller and the projection display device 100 may include infrared protocol communication, Bluetooth protocol communication, or wireless or other wired communication. For example, a user may control the projection display device 100 by inputting user commands through buttons on the remote controller, voice input, or control panel input.

[0063] In addition, the control device 200 can also use a mobile terminal, a tablet computer, a computer, a laptop computer, and other smart devices to control the projection display device 100 .

[0064] In one possible implementation, the smart device 300 can communicate with the software application installed on the projection display device 100 via a network communication protocol, thereby achieving one-to-one control operations and data communication. Furthermore, the audio and video content displayed on the smart device 300 can also be transmitted to the projection display device 100 for synchronized display.

[0065] In one possible implementation, the projection display device 100 also communicates data with the server 400 via various communication methods. The projection display device 100 may be connected to a LAN (Local Area Network), a WLAN (Wireless Local Area Network), or other networks. The server 400 may provide various content and interactions to the projection display device 100. In addition to providing broadcast reception television functionality, the projection display device 100 may also provide intelligent network television functionality that supports computer support.

[0066] In one possible implementation, during use, since the white balance of the projection display device is easily affected by light source conditions such as light source, light path, and light effect, color cast may occur when displaying the picture, resulting in white balance imbalance. Therefore, it is necessary to adjust the white balance of the projection display device to ensure that the projection display device can accurately display colors.

[0067] To facilitate understanding of the white balance adjustment solution provided in the embodiments of the present application, the optical path architecture, color gamut plane, phosphor wheel structure, and color coordinates of the projection display device are first introduced using a laser projection device as an example.

[0068] Refer to Figure 6, which is a schematic diagram of the optical path architecture of the laser projection device provided in an embodiment of the present application, including: a red laser light source 6001, a green laser light source 6002, a blue laser light source 6003, a first dichroic mirror 6004, a reflecting mirror 6005, a second dichroic mirror 6006, a lens 6007, a diffusion wheel 6008, a light pipe 6009, a total reflection prism 6010, a first galvanometer 6011, a second galvanometer 6012, a projection lens 6013, and an illuminometer 6014.

[0069] It should be noted that the first dichroic mirror 6004 can transmit red laser light and reflect green and blue laser light; the reflector 6005 can reflect green laser light and change the optical path of green laser light; the second dichroic mirror 6006 can reflect green laser light and transmit blue laser light; after the red laser light, green laser light and blue laser light are combined, they enter the diffusion wheel 6008 and are homogenized by the light pipe 6009. The homogenized light is irradiated by the total reflection prism 6010, and then enters the first galvanometer mirror 6011 after passing through the total reflection prism 6010. The second galvanometer mirror 6012 then shifts the light pixel information and finally projects it into the projection lens 6013 to project the picture.

[0070] Among them, the illuminance meter 6014 can detect the intensity and coordinates of the wavelength light signals of the red light source, the green light source, and the blue light source.

[0071] For example, FIG7 is a schematic diagram of color coordinate values ​​provided in an embodiment of the present application, and FIG7 shows the spectral peak power of a blue light source, the spectral peak power of a green light source, and the spectral peak power of a red light source.

[0072] For example, FIG8 is a schematic diagram of a fluorescent wheel structure provided in an embodiment of the present application, which can be applied to the laser projection device shown in FIG6 above, and takes a blue laser as an example.

[0073] Within the annular region of the phosphor wheel, the R region contains red phosphor, the G region contains green phosphor, and the B region transmits blue laser light. During one rotation, the angles occupied by these regions vary. When the laser shines on the phosphor wheel, the duration of each primary color produced varies. Due to the persistence of vision of the human eye, the continuously output primary colors (e.g., red, green, blue, and optionally yellow) are perceived by the human eye as a mixture of these primary colors, creating white light.

[0074] See Figure 9, which is a schematic diagram of a color gamut provided in an embodiment of the present application. The three regions within the horseshoe-shaped area are red, green, and blue. The green range is located in the upper left region of the horseshoe-shaped area; the closer to the edge of the region, the purer the green color. Similarly, the blue range is located in the lower left region; the closer to the lower left region, the purer the blue color. The red range is located in the lower right region; the closer to the lower right region, the purer the red color.

[0075] When the white balance color coordinates shift within this color gamut, the color shifts toward that area. The black circular area within the horseshoe-shaped range represents the white balance color coordinates. If the range is outside this range, the white will be color-shifted (white balance imbalance). If the x coordinate is too large, the white will be pink or yellow, etc. If x is too small, the white will be bluish. If the y coordinate is too large, the white will be greenish. If the y coordinate is too small, the white will be pink or purple.

[0076] Based on this, the embodiments of the present application provide a projection display device and a white balance adjustment method to monitor and adjust the white light color coordinates of the projection display device, so as to gradually reduce the deviation of the color coordinate values, thereby ensuring that the projection display device can always output white light that meets the desired color standards under different usage environments and conditions.

[0077] In order to explain the white balance adjustment method provided by the embodiment of the present application in more detail, the process of performing white balance adjustment on the projection display device provided by the embodiment of the present application will be described in detail below in combination with the specific structure.

[0078] It should be understood that the projection display device shown in the following Figure 10 may also include the device in any of the structures shown in Figures 1-6 above. The embodiment of the present application only uses the processor therein as the execution body to explain the implementation process of the white balance adjustment method, and does not constitute a limitation on the specific structure of the projection display device.

[0079] 10 , when executing the white balance adjustment method provided in the embodiment of the present application, the projection display device includes: a primary color light source 1001 , a digital micromirror device 1002 , a projection lens 1003 and a processor 1004 .

[0080] The primary light source 1001 is configured to emit primary light. The digital micromirror device 1002 is located on the light-emitting side of the primary light source and is configured to modulate the primary light and reflect the modulated light toward the projection lens 1003. The projection lens 1003 is configured to image the light beam emitted by the digital micromirror device 1002. The processor 1004 is connected to the digital micromirror device 1002 and is configured to execute the white balance adjustment method provided in FIG. 11 below.

[0081] As an example, the primary color light source 1001 can be a laser, or an LED (Light Emitting Diode) light source, etc. If the primary color light source 1001 is a laser, it can be a monochromatic laser, a dual-color laser, or a tri-color laser, etc., and this embodiment of the application does not impose any limitation on this.

[0082] Among them, the multiple primary color lights that constitute the pixel color are related to the primary color light source 1001, which can be a light source of three primary colors (abbreviated as three primary colors or three primary colors) of RGB (Red Greed Blue), or a light source of four primary colors of RGBY (Red Greed Blue Yellow), etc. The embodiment of the present application does not limit the type of primary colors.

[0083] Referring to FIG. 11 , FIG. 11 is a flow chart illustrating a white balance adjustment method provided in an embodiment of the present application. This method can be applied to the projection display device shown in FIG. 1-6 and FIG. 10 , and is specifically applied to a processor in the projection display device. The method includes the following steps:

[0084] Step 1101: driving the primary color light sources to emit primary color lights, and obtaining first color coordinate values ​​of white light generated by mixing the primary color lights.

[0085] In one possible implementation, an embodiment of the present application adds a color sensor to a projection display device. A color sensor, as an optical sensor, typically operates based on the photoelectric effect and can sense and measure the intensity and color characteristics of light. In a projection display device, the color sensor can be positioned somewhere on the projected image to capture light from the projected image.

[0086] In the embodiment of the present application, the color sensor can be used to collect the color coordinate values ​​of the primary color light emitted by the primary color light source. In addition, the color sensor can also be used to collect the brightness value of the primary color light, which is not limited in the embodiment of the present application.

[0087] As an example, an embodiment of the present application sets an illuminometer at a light-transmitting position in the optical engine unit to collect the brightness and color coordinate values ​​emitted by the primary color light source, and sets another illuminometer at a light-transmitting position on the upper shell of the laser projection device to collect the brightness and color coordinate values ​​of the ambient light. Alternatively, a single illuminometer can be set to collect both the brightness and color coordinate values ​​emitted by the primary color light source and the brightness and color coordinate values ​​of the ambient light.

[0088] In a possible implementation, the primary color light sources include a red light source, a green light source, and a blue light source. Correspondingly, the primary color lights include red light emitted by the red light source, green light emitted by the green light source, and blue light emitted by the blue light source.

[0089] It should be noted that the first color coordinate value of white light can reflect the white balance state of the projection display device in the current environment scene. However, the white balance of a projection display device is easily affected by factors such as the light source, light path, light effect, and ambient light, resulting in color cast and white balance imbalance in the displayed image. Therefore, the white balance state of the projection display device needs to be monitored before leaving the factory and during user use. If the white balance is imbalanced, the white balance should be adjusted in a timely manner to ensure the projection display effect of the projection display device.

[0090] It should be understood that the color of objects may vary under different light sources (such as sunlight, fluorescent lighting, and incandescent lighting) due to the different color temperatures of the light sources. For example, objects under incandescent lighting may appear yellowish or reddish, while they appear normal under sunlight. White balance technology is used to correct this color deviation caused by different light source color temperatures, thereby making the projected image more realistic and natural.

[0091] Considering that the environmental scenes in which the projection display device is located may be different, the implementation methods of obtaining the first color coordinate value of white light in different environmental scenes (different lighting conditions) will also be different, which will be introduced below.

[0092] In one possible implementation, the implementation process of the above step 1001 can be: driving a red light source to emit red light to project a red chart, and obtaining the color coordinate value of the red light based on the projected red chart; driving a green light source to emit green light to project a green chart, and obtaining the color coordinate value of the green light based on the projected green chart; driving a blue light source to emit blue light to project a blue chart, and obtaining the color coordinate value of the blue light based on the projected blue chart; determining the first color coordinate value based on the color coordinate value of the red light, the color coordinate value of the green light, and the color coordinate value of the blue light.

[0093] A chart is a standardized image used to test the color, brightness, contrast, and other performance characteristics of projection display devices. It typically contains a series of specific colors and patterns, allowing the performance of the projection display to be evaluated by observing and analyzing these images. Charts can be static or dynamic, depending on the testing requirements and the type of projection display device.

[0094] It should be understood that the RGB color model is based on the principle of additive color mixing of the three primary colors: red, green, and blue. By adjusting these three colors, different colors can be synthesized. In other words, in projection display devices, the RGB primary light source is the basis for producing various colors.

[0095] When a projection display device projects a red chart, only the red light source is activated, while the green and blue light sources are turned off or at low brightness. The Color Sensor then measures the light from the projected image and obtains the color coordinates of the red light, which represent the position of the red light source on a chromaticity diagram (e.g., CIE1931). Similarly, by projecting a red chart, a green chart, and a blue chart in sequence, the color coordinate values ​​of the red, green, and blue light can be obtained.

[0096] As an example, the color coordinate value of red light is (x r ,y r ), the color coordinate value of green light is (xg ,y g ), the color coordinate value of blue light is (x b ,y b ).

[0097] It should be noted that projection charts typically adhere to certain standards and specifications. By using standardized charts, errors that may arise under different test conditions can be eliminated, thereby improving measurement accuracy. Therefore, projection charts can serve as a relatively stable test object, reducing the influence of these interfering factors and allowing for more accurate acquisition of the color coordinate values ​​of the light source.

[0098] Furthermore, since white light is produced by mixing red light, green light and blue light, the first color coordinate value of white light can be determined based on the color coordinate value of red light, the color coordinate value of green light and the color coordinate value of blue light through color space conversion and other processing methods.

[0099] In some embodiments, laser projection equipment is factory-installed in a fixed test environment and the laser duty cycle is adjusted using a preset program to achieve white balance correction, thereby ensuring that white balance differences between devices are minimal. However, after the laser projection equipment is delivered to the user, the user's usage scenario may differ from the previous test environment in terms of brightness, color temperature, etc. In addition, long-term use of laser projection equipment can also lead to inconsistent laser attenuation ratios. If white balance adjustments are still performed according to the preset program, the white color displayed by the laser projection equipment will be biased, seriously affecting the user experience.

[0100] That is, in the user's usage scenario, the projection display device will also be affected by the ambient light, which may cause the color coordinate value to shift. Therefore, during the white balance adjustment process, when obtaining the first color coordinate value of white light, the influence of ambient light needs to be considered.

[0101] In another possible implementation, the implementation process of the above step 1001 can be: obtaining the second color coordinate value of the ambient light; driving the primary color light source to emit primary color light, and obtaining the third color coordinate value of the mixed light, where the mixed light refers to the light produced by the mixture of ambient light and primary color light; and determining the first color coordinate value based on the second color coordinate value and the third color coordinate value.

[0102] The ambient light refers to the light in the environment where the projection display device is located, such as natural light, indoor lighting, etc.

[0103] Since the color and brightness of ambient light will interfere with the color of the projected image, causing the color coordinate value to shift, when detecting the first color coordinate value of the white light currently projected by the projection display device, by introducing ambient light, the actual usage scenario can be simulated during the calibration process, thereby improving the accuracy and practicality of the calibration.

[0104] In one possible implementation, determining the first color coordinate value based on the second and third color coordinate values ​​can include comparing the second and third color coordinate values ​​to establish a corresponding relationship between the color coordinate values ​​under mixed light and the color coordinate values ​​under ambient light. This relationship characterizes the degree of influence of ambient light on the color coordinate values. Based on this relationship, the degree of interference of ambient light on the color of the projected image can be predicted, thereby determining the first color coordinate value of white light.

[0105] Among them, the corresponding relationship represents the influence of ambient light on the color coordinate value, which is a nonlinear relationship supported by test data.

[0106] As an example, Table 1 below shows the influence of ambient light on color coordinate values, and shows the color coordinate values ​​corresponding to different test conditions.

[0107] Table 1

[0108] As shown in Table 1, the first test condition was with ambient light off, with the projection display device projecting both a primary color chart and a white chart. The second test condition was with the laser off, with only ambient light. The third test condition was with ambient light on, with the projection display device projecting both a primary color chart and a white chart. The second test condition served as the control group, controlling for ambient light to analyze how the color coordinates were affected by ambient light.

[0109] As an example, if the ambient light is yellow light, when the ambient light is turned on, compared to when the ambient light is turned off: the horizontal coordinate of the color coordinate value of white light is larger, the vertical coordinate of the color coordinate value of white light is larger, and the horizontal coordinate of the color coordinate value of the primary color light is smaller, and the vertical coordinate of the color coordinate value of the primary color light is larger.

[0110] The data in Table 1 shows that ambient light affects the color coordinate values. When the ambient light is on, the effects of ambient light and projection light on the coordinate values ​​are not simply the sum of the two. It is understandable that the color coordinate values ​​when the ambient light is on are not equal to the sum of the color coordinate values ​​of the ambient light alone plus the color coordinate values ​​of the projection light alone.

[0111] In some embodiments, a corresponding relationship B=f(A) between the color coordinate values ​​under mixed light and the color coordinate values ​​under ambient light is determined based on the second color coordinate value A and the third color coordinate value B. Here, B is the color coordinate value of each primary color and the color coordinate value of white under mixed light, or B is the brightness value and color coordinate value of each primary color and the brightness value and color coordinate value of white under mixed light; and A is the color coordinate value under ambient light, or the brightness and color coordinate value under ambient light.

[0112] The above embodiment determines the influence of ambient light on the color coordinate value through data analysis, and this influence is nonlinear. Therefore, white balance adjustment is not a simple matter of slowing down the color coordinate value under ambient light, and step 1102 needs to be performed.

[0113] Step 1102: When the deviation between the first color coordinate value and the standard color coordinate value is greater than the deviation threshold, the light-emitting parameters of the primary color light source are adjusted based on the standard color coordinate value so that the deviation between the color coordinate value of the white light generated by the mixture of the primary color lights emitted by the adjusted primary color light source and the standard color coordinate value is less than or equal to the deviation threshold, and the standard color coordinate value is the white light color coordinate expected to be achieved by the projection display device.

[0114] Among them, the deviation threshold is a pre-set threshold used to characterize the white balance, which is usually set to 0 to determine whether the current coordinate value is consistent with the standard color coordinate value. It should be noted that the user can feel the change in color temperature of the laser projection device display screen, such as warm or cool colors, but due to physiological limitations, the user cannot perceive the change in color temperature between two color coordinate values ​​with a very small difference, and errors in the adjustment of white balance are allowed. Therefore, this application does not limit the specific value of the deviation threshold.

[0115] Standard color coordinates refer to the coordinate values ​​of a color on a chromaticity diagram under specific light sources and viewing conditions. For projection display devices, these coordinates are typically obtained through precise measurement and calibration at the factory to ensure accurate color reproduction in various application scenarios.

[0116] As an example, the standard color coordinate value is the white balance index of the projection display device when it leaves the factory. It is understandable that the standard color coordinate values ​​corresponding to different application scenarios are different. The standard color coordinate value corresponding to the target sales area can be determined based on the sales area of ​​the projection display device; the standard color coordinate value corresponding to the target model can also be determined based on the model of the projection display device; or the standard color coordinate value set by the user can be received; it is determined specifically according to actual needs and is not limited in the embodiments of this application. For example, since people in different regions have different eye colors, different color studies have different sensitivities to different colors. For example, blue eyes are more sensitive to red stimuli. Therefore, different standard color coordinate values ​​can be set for different sales areas. For example, for laser projection equipment in the sales area where people with blue eyes are located, the red ratio in the set standard color coordinate value can be appropriately lower; for laser projection equipment in the sales area where people with other eye colors are located, the red ratio in the set standard color coordinate value can be appropriately higher.

[0117] As another example, given the diverse user scenarios and the varying color requirements of different application scenarios, different standard color coordinate values ​​are set. For example, home theater settings typically pursue a natural and comfortable viewing experience. Therefore, standard color coordinate values ​​are often set to a color range close to that observed by the human eye under natural light. Common standard color coordinate values ​​may include (0.3127, 0.3290) under D65 light source. These values ​​ensure that the projected image presents colors close to those in the real world. Commercial display scenarios often require the projected image to have vivid, eye-catching colors to attract the audience's attention. Therefore, standard color coordinate values ​​may be set to a more saturated and bright color range. For example, some laser projectors used in commercial displays may use color coordinate values ​​that are more red or green to enhance the visual impact of the image. In the field of professional photography / videography, color accuracy is extremely demanding. Therefore, standard color coordinate values ​​are often set according to a specific color space (such as sRGB, Adobe RGB, etc.) to ensure that the projected image accurately reproduces the colors when it was shot. For example, standard color coordinate values ​​in the sRGB color space might include red coordinates such as (0.64, 0.33) and green coordinates such as (0.15, 0.84). Educational and conference scenarios typically require projected images to be clear and easy to read, while also ensuring accurate color. Therefore, standard color coordinate values ​​are typically set within a range that ensures the clarity and color accuracy of text, charts, and other content. For example, color coordinate values ​​close to those of a D65 light source might be used to ensure natural, clear colors in projected images in classrooms or conference rooms.

[0118] In a possible implementation, the implementation process of step 1102 may include the following steps:

[0119] (1) Determine the target parameters based on the standard color coordinate values.

[0120] The target parameters include the target luminous duration of the primary color light source and / or the target illuminance of the primary color light.

[0121] In a possible implementation, the target parameter is calculated using the following formula (1) based on the standard color coordinate value, the color coordinate value of red light, the color coordinate value of green light, and the color coordinate value of blue light.

[0122] In the above formula (1), x is the horizontal coordinate of the standard color coordinate value, y is the vertical coordinate of the standard color coordinate value, D r is the target luminous duration of the red light source, D g is the target luminous duration of the green light source, D b is the target luminous duration of the blue light source, Y ris the target illuminance of the red light, Y g is the target illuminance of the green light, Y b is the target illuminance of the blue light; x r is the abscissa of the color coordinate value of the red light, x g is the abscissa of the color coordinate value of the green light, x b is the abscissa of the color coordinate value of the blue light, y r is the ordinate of the color coordinate value of the red light, y g is the ordinate of the color coordinate value of the green light, y b is the ordinate of the color coordinate value of the blue light, C r =Y r / y r , C g =Y g / y g , C b =Y b / y b .

[0123] The standard color coordinate values ​​in the above formula also satisfy the following formulas (2)-(4). D r +D g +D b =100% (4)

[0124] Among them, X, Y, Z are coordinates in the color space; x, y, z are coordinates in the plane coordinate system.

[0125] Based on the above formula, according to Grassmann's color law, we know that: Y m =Y r +Y g +Y b =D r Y r +D g Y g +D b Y b (5)

[0126] Among them, Y m It is the luminous flux of the mixture of red light, green light and blue light. r 、Y g 、Y b , the greater the current supplied to each primary color light source, the greater the corresponding value.

[0127] Based on the above formula, it can be seen that the first color coordinate value collected by the projection display device is related to the luminous duration of the primary color light source and the illuminance of the primary color light. Therefore, in the embodiment of the present application, when the deviation between the first color coordinate value of the white light and the standard color coordinate value is greater than the deviation threshold, the first color coordinate value is adjusted by adjusting the target parameters, that is, the target luminous duration of the primary color light source, and / or the target illuminance of the primary color light, so that the deviation between the color coordinate of the white light generated by the mixing of the primary color lights emitted by the adjusted primary color light source and the standard color coordinate value is less than or equal to the deviation threshold.

[0128] (2) According to the target parameters, the luminous parameters of the primary color light sources are adjusted so that the deviation between the color coordinate value of the white light generated by the mixture of the primary color lights emitted by the adjusted primary color light sources and the standard color coordinate value is less than or equal to the deviation threshold.

[0129] In one possible implementation, the initial light emission duration of the primary light source is adjusted to the target light emission duration, and / or the initial illuminance of the primary light is adjusted to the target illuminance, so that the deviation between the coordinate value of the white light generated by the mixture of the primary light emitted by the adjusted primary light source and the standard color coordinate value is less than or equal to the deviation threshold.

[0130] It should be noted that each time an adjustment is completed, the color coordinate values ​​of the white light must be re-acquired to determine whether the adjusted color coordinate values ​​are less than the deviation threshold. If the color coordinate values ​​of the white light generated by the mixture of the primary light sources are greater than the deviation threshold, the above adjustment process is repeated until the deviation between the color coordinate values ​​of the adjusted white light and the standard color coordinate values ​​is less than the deviation threshold. This ensures that the projection display device, when projecting and displaying images according to the adjusted color coordinate values, has no color cast and maintains a white balance effect.

[0131] In some embodiments, after the target parameters are determined, the corresponding relationship between the first color coordinate value and the target parameters may be stored in the projection display device.

[0132] In this way, when the projection device obtains that the color coordinate value of the white light generated by the mixture of the primary light emitted by the primary light sources is the first color coordinate value, the emission parameters of the primary light sources can be adjusted according to the target parameters to ensure the white balance effect.

[0133] In summary, when the embodiment of the present application detects that the deviation between the first color coordinate value and the preset standard color coordinate value is greater than the deviation threshold, the white balance adjustment program is activated. Based on the standard color coordinate value, the processor adjusts the luminous parameters of the primary color light source to gradually reduce the deviation of the color coordinate value. Through this automatic correction mechanism, the projection display device can ensure that it always outputs white light that meets the desired color standard under different usage environments and conditions. In this way, through precise color control and correction, the projection display device can reduce color distortion and deviation, improve image clarity and contrast, and thereby enhance the stability and consistency of the display.

[0134] After adjusting the white balance of a projection display device, the current duty cycle of the primary color light sources in the projection display device will change. Typically, the current duty cycle is linearly related to the current value; a larger current duty cycle corresponds to a larger current value. Therefore, when the current duty cycle changes, the brightness of the primary color light emitted by the primary color light sources in the projection display device also changes. This can cause the image projected by the projection display device (especially grayscale images) to exhibit color casts, and the image brightness perceived by the user will also be reduced, impacting the user experience.

[0135] Taking a laser projection display device as an example, the following relationship exists for the laser projection display device:

[0136] Among them, L1 is the brightness of the laser projection display device perceived by the human eye, which can be expressed by luminous flux; L laser It is the brightness of the primary color light source in the projection display device, and is also expressed by luminous flux; L pixel is the pixel brightness, which is represented by the pixel grayscale value. λ is a parameter preset in the projection display device, and its value can be 2.2.

[0137] It can be seen from the above formula (6) that the brightness of the laser projection display device perceived by the human eye is not only related to the brightness of the laser light source, but also to the pixel brightness.

[0138] As an example, for the primary color light source (R, G, B) components in a projection display device with a 10-bit color depth, the pixel brightness L pixel The value range is 0-1023.

[0139] Taking a monochrome laser projection device as an example, after the white balance of the monochrome laser projection device is adjusted, the brightness L of the laser light source will be adjusted. laser , at this time if the original video signal pixel brightness L is still used pixelIf the value is set too low, the displayed image will be distorted in brightness and color, and grayscale content will be colored. For example, when displaying a 32-grayscale image, some grayscales, such as 12 and 13, will appear reddish.

[0140] Based on this, in order to ensure that the display effect of the projection display device remains unchanged when projecting an image after the white balance is adjusted, it is necessary to compensate the pixels of the target image to be displayed according to the brightness of the adjusted primary color light source to make up for the impact of the reduced brightness of the primary color light source.

[0141] For projection display devices, the following relationship also exists: L2 = KU λ (7)

[0142] Wherein, L2 is the actual output brightness of the projection display device, which can be expressed by luminous flux; U is the input video signal of the projection display device, and λ is a parameter preset in the projection display device.

[0143] It can be seen that for a projection display device, the actual output brightness L2 and the input video signal U have an exponential relationship, not a linear relationship.

[0144] Regarding image pixel compensation, its principle can be explained by the following formulas (8)-(16).

[0145] First, based on the above formula (6), the following formulas (8)-(9) can be derived.

[0146] In the above formula (8), “typical” represents the values ​​of various parameters before white balance adjustment (i.e., before adjusting the brightness of the primary color light source, referred to as before dimming). For example, L typical The brightness of the projection display device perceived by the human eye before dimming can be expressed by luminous flux. laser-typical is the brightness of the primary color light source before dimming, L pixel-typical is the pixel brightness before dimming, and λ is a parameter preset in the projection display device.

[0147] In the above formula (9), “reduce” represents the parameter values ​​after white balance adjustment (i.e., after adjusting the brightness of the primary color light source, referred to as dimming). For example, L reduce The brightness of the projection display device perceived by the human eye after dimming can be expressed by luminous flux. laser-reduce is the brightness of the primary color light source after dimming, L pixel-reduce is the pixel brightness after dimming, and λ is a parameter preset in the projection display device.

[0148] Generally, the output brightness of the primary color light source after dimming is smaller than the output brightness of the primary color light source before dimming. Therefore, if the brightness of the projection display device perceived by the human eye before and after dimming needs to be kept unchanged, the pixel brightness needs to be increased, that is, the pixel brightness after dimming needs to be compensated to ensure that the brightness of the image observed by the human eye does not change significantly and there is no color cast when displaying multi-grayscale images.

[0149] Furthermore, if it is necessary to keep the brightness of the projection display device perceived by the human eye unchanged before white balance adjustment (i.e., before dimming) and after white balance adjustment (i.e., after dimming), then based on the above formulas (8) and (9), the following formula (10) needs to be satisfied. L typical =L reduce (10)

[0150] That is, the following formula (11) needs to be satisfied.

[0151] For ease of explanation, a ratio value k is introduced here, and k is set to satisfy the following formula (12).

[0152] Based on formula (12), the following formulas (13)-(14) can be further derived.

[0153] Furthermore, a parameter k′ is introduced, and k′ is set to satisfy the following formula (15).

[0154] It can be seen from the above formulas (8)-(16) that after white balance adjustment, when the brightness of the primary color light source is reduced to 1 / k of the brightness before dimming, the pixel grayscale value of the video image before dimming is multiplied by the parameter k′, which can compensate the pixel brightness accordingly, avoid the color cast problem, and also ensure that the brightness of the projection display device perceived by the human eye before and after dimming remains the same.

[0155] In summary, after the projection display device performs white balance adjustment, the brightness of the primary color light source will change. At this time, in order to avoid the projection display device calling the preset basic pixel grayscale value and causing color cast problems, and to avoid the problem of the human eye perceiving the brightness of the projection display device as reduced before and after the white balance adjustment, the basic pixel grayscale value needs to be calibrated.

[0156] It should be noted that projection display devices typically have multiple sets of preset current duty cycles corresponding to the primary color light sources, as well as a set of pixel grayscale values. When adjusting white balance, these preset current duty cycles and pixel grayscale values ​​can be directly used to control the digital micromirror device to display the image. However, if the current duty cycle after white balance adjustment deviates from the multiple preset sets of current duty cycles, continuing to use the preset pixel grayscale values ​​will result in color casts in some grayscales of the image.

[0157] Based on this, an embodiment of the present application also provides a white balance adjustment method, so that after the projection display device performs white balance adjustment, the processor receives the target current duty cycle corresponding to the multiple primary color light sources that constitute the pixel color sent by the main control device. If the target current duty cycle does not match the basic current duty cycle, the target pixel grayscale value corresponding to the target current duty cycle is determined, and based on the target current duty cycle and the target pixel grayscale value, the digital micromirror device is controlled to display the target image based on the target current duty cycle and the target pixel grayscale value. In this way, the color cast problem caused by directly calling the basic pixel grayscale value corresponding to the basic current duty cycle pre-stored in the projection display device can be avoided, and the problem of reduced brightness of the projection display device perceived by the human eye can also be avoided.

[0158] 12 is a schematic diagram of the architecture of a white balance adjustment system provided in an embodiment of the present application. A main control device 1201 is connected to a projection display device 1202 and an illuminance meter 1203 respectively.

[0159] In the embodiment of the present application, main control device 1201 controls projection display device 1202 to enter a white balance adjustment mode, and projection display device 1202 sequentially projects multiple test images (which may also be the standard charts described above, i.e., red, green, and blue charts). Illuminance meter 1203 is used to detect the color coordinates and brightness values ​​of the multiple test images as projection display device 1201 sequentially projects the multiple test images. The colors of the multiple test images are different, such as a red test image, a yellow test image, and a blue test image.

[0160] The main control device 1201 determines the target current duty ratios corresponding to different primary color light sources when the primary color light sources of the projection display device 1202 reach a better white balance under the current projection environment based on the color coordinates and brightness values ​​of the test image measured by the illuminometer 1203 .

[0161] As an example, the main control device may be a terminal with data calculation and processing capabilities, such as a PC (personal computer), a tablet computer, or a smart phone.

[0162] Furthermore, after determining the target current duty cycle, the main control device 1201 sends the target current duty cycle to the projection display device 1202 .

[0163] 13, which is a schematic diagram of the hardware structure of a main control device and a projection display device provided by an embodiment of the present application. The main control device runs a white balance algorithm and can communicate with the projection display device via a USB port.

[0164] In a possible implementation, the projection display device includes a multimedia board and a display board, wherein the multimedia board may include a USB signal switching switch, a SOC (System on Chip), and a flash memory FLASH1 device.

[0165] The display panel may include multiple devices such as DLP ASIC (Digital Light Processing Application Specific Integrated Circuit), flash memory FLASH2, memory E2PROM1, MCU (Micro Control Unit), memory E2PROM2, etc.

[0166] The data transmission mode between the DLP ASIC and the flash memory FLASH2 is parallel data transmission, the DLP ASIC communicates with E2PROM2 and E2PROM1 based on the I2C protocol, and communicates with the SOC based on the USB protocol.

[0167] In one possible implementation, the multimedia board can communicate with the host control device via a USB port. When adjusting the white balance of the projection display device, the host control device can transmit data to the MCU's corresponding E2PROM2 for storage based on the I2C protocol. E2PROM2 stores the current data sets corresponding to each primary color light source for white balance, including information such as current duty cycle and current value.

[0168] In one possible implementation, a USB signal switch can be used to control the SOC or PC to transmit data to the DLP ASIC based on the USB protocol, enabling the DLP ASIC to execute the corresponding instructions. If the USB port power pin is high, data transmission can be carried out through the SOC. If the USB port power pin is low, data transmission can be carried out through the PC.

[0169] The above is only an exemplary hardware architecture, and the embodiments of the present application do not limit the specific hardware architecture of the projection display device and the main control device.

[0170] Referring to Figure 14, Figure 14 is a flow chart illustrating another white balance adjustment method provided in an embodiment of the present application. This method can compensate for pixel brightness after the projection display device performs the white balance adjustment shown in Figure 11 above. Similarly, this method can also be applied to the projection display devices shown in Figures 1-6 above, as well as Figures 10, 12, and 13, and is specifically applied to a processor in the projection display device. The method includes the following steps:

[0171] Step 1401: Receive a target current duty cycle corresponding to a primary color light source sent by a master device, where the target current duty cycle is used to represent the brightness of the primary color light source.

[0172] It should be noted that the current duty cycle can represent the magnitude of the current value. The current value and the current duty cycle are in a linear relationship. The larger the current duty cycle, the larger the current value. The current is the driving current used to control the emission of the primary color light source. When the driving current corresponding to a primary color light source is large, the brightness of the corresponding primary color light source is high. Therefore, after the projection display device performs white balance, the main control device can determine the target current duty cycle corresponding to the primary color light source based on the current environmental scene. The target current duty cycle has changed compared to the current duty cycle of the projection display device before the white balance adjustment, that is, the brightness of the primary color light source controlling the projection display device has changed.

[0173] A set of current duty cycles includes current duty cycles corresponding to multiple primary color light sources. For example, the target current duty cycle includes a target current duty cycle corresponding to a red light source, a target current duty cycle corresponding to a green light source, and a target current duty cycle corresponding to a blue light source.

[0174] Step 1402 : If the target current duty cycle does not match the base current duty cycle, determine a target pixel grayscale value corresponding to the target current duty cycle.

[0175] Similarly, the basic current duty cycle also includes a basic current duty cycle corresponding to a red light source, a basic current duty cycle corresponding to a green light source, and a basic current duty cycle corresponding to a blue light source.

[0176] In one possible implementation, if the target current duty cycle of each primary color light source included in the target current duty cycle is the same as the basic current duty cycle of the corresponding primary color light source in the basic current duty cycle, or the difference between the target current duty cycle and the basic current duty cycle of the corresponding primary color light source is within an error range, then it is determined that the target current duty cycle matches the basic current duty cycle.

[0177] As an example, the target current duty cycle includes the current duty cycles corresponding to the RGB primary colors A0, B0, and C0, respectively. The basic current duty cycle includes n groups of data. The first group of basic current duty cycles includes the current duty cycles corresponding to the RGB primary colors A1, B1, and C1, respectively. The second group of basic current duty cycles includes the current duty cycles corresponding to the RGB primary colors A2, B2, and C2, respectively. The nth group of basic current duty cycles includes the current duty cycles corresponding to the RGB primary colors An, Bn, and Cn, respectively.

[0178] If A0=A2, B0=B2, and C0=C2, it can be determined that the target current duty cycle matches the second set of basic current duty cycles.

[0179] Alternatively, the current duty ratios A0, B0, and C0 corresponding to the RGB primary colors included in the target current duty ratio are all different from the current duty ratios corresponding to the RGB primary colors included in the n groups of basic current duty ratios, but the difference between A0 and A1 is less than the first preset range, the difference between B0 and B1 is less than the second preset range, and the difference between C0 and C1 is less than the third preset range. At this time, it can also be determined that the target current duty ratio matches the first group of basic current duty ratios.

[0180] Among them, the first preset range, the second preset range and the third preset range can be the same or different, and can be set according to actual needs. The embodiment of the present application does not limit this.

[0181] In some embodiments, in addition to a preset base current duty cycle, the projection display device also stores a set of base pixel grayscale values. If the target current duty cycle matches the set of base current duty cycles, the preset base pixel grayscale values ​​can be used directly for image display without determining the target pixel grayscale value.

[0182] In another possible implementation, if the target current duty cycle of any primary color light source included in the target current duty cycle is different from the current duty cycle of the corresponding primary color light source in the basic current duty cycle, or the difference between the target current duty cycle and the current duty cycle of the corresponding primary color light source is not within an error range, it is determined that the target current duty cycle does not match the basic current duty cycle.

[0183] As an example, if A0, B0, and C0 in the target current duty cycle are all different from An, Bn, and Cn in the n groups of basic current duty cycles, that is, A0≠An, B0≠Bn, and C0≠Cn, or if only the current duty cycle corresponding to one primary color is different, that is, A0=An, B0=Bn, and C0≠Cn, then it can be determined that the target current duty cycle does not match the n groups of basic current duty cycles.

[0184] When the difference between the current duty cycle of any primary color in the target current duty cycle and the current duty cycle of the corresponding primary color in the basic current duty cycle is not within the preset range, for example, A0=An, B0=Bn, C0≠Cn, but since the difference between C0 and Cn is not within the preset range, that is, exceeds the preset range, it can be determined that the target current duty cycle does not match the multiple sets of basic current duty cycles.

[0185] Furthermore, when the target current duty cycle does not match the base current duty cycle, in order to avoid color cast problems and low image brightness problems, the pixel brightness needs to be compensated. At this time, the compensated target pixel grayscale value needs to be determined based on the target current duty cycle.

[0186] In one possible implementation, the implementation process of step 1402 may be: receiving pixel correction information sent by the main control device, the pixel correction information including the brightness value of the primary color light source, the frame rate of the input signal corresponding to each primary color light, and the grayscale of the input signal; and determining the target pixel grayscale value corresponding to the target current duty cycle according to the pixel correction information.

[0187] Taking the three primary colors RGB as an example, when calibrating the basic pixel grayscale value and determining the target pixel grayscale value, the bitplane (bit plane) time accumulation can be performed based on the brightness value of the illumination beam output by the light source 401, the frame rate of the red input signal, and the grayscale of the red input signal, that is, the display time can be determined to output the image.

[0188] As an example, the grayscale of the red input signal can be divided into m bitplanes, and the corresponding m bitplane charts can be displayed respectively. The brightness or grayscale value of each bitplane chart can be determined, thereby determining the grayscale value of the target pixel corresponding to the primary color red.

[0189] Furthermore, the display time of each bitplane card can be determined based on the weight of each bitplane, so as to display the image based on the display time. Please refer to Table 2, which is used to represent the corresponding relationship between the bitplane and the display time.

[0190] Table 2

[0191] Similarly, green and blue calibration can be performed in sequence. Since the white image is composed of red, green and blue images, when the red, green and blue calibration is completed, it can be indicated that the white image calibration has passed.

[0192] Step 1403: Control the digital micromirror device to display the target image according to the target current duty cycle and the target pixel grayscale value.

[0193] In some embodiments, after determining the target current duty cycle, the projection display device may further use the target current duty cycle as a basic current duty cycle and store a correspondence between the target current duty cycle and the target pixel grayscale value.

[0194] In this way, if it is detected in subsequent use that the current duty cycle of the primary color light source is the target current duty cycle, the target pixel grayscale value can be directly obtained without recalculation.

[0195] In some embodiments, the projection device may further receive a target current value sent by the main control device, the target current value indicating that the image mode of the projection display device is a white balance mode; and store a corresponding relationship between the target current value and the target current duty cycle.

[0196] In this way, if the current value of the primary color light source is detected to be the target current value during subsequent use, the target pixel grayscale value can be directly obtained without the need for recalculation.

[0197] As an example, the correspondence between the target current value and the target current duty cycle can be stored in a first memory, and the correspondence between the target current duty cycle and the target pixel grayscale value can be stored in a second memory. The first memory and the second memory can be E2PROM (Electrically-Erasable Programmable Read-Only Memory) or other memories, and this application does not impose any restrictions on this.

[0198] In some embodiments, after the target current value and the target current duty cycle are stored in the second memory, if the projection display device performs white balance adjustment again, the main control device generates a new set of target current duty cycles and records the new target current duty cycle as the first target current duty cycle. After receiving the first target current duty cycle, the projection display device can match the first target current duty cycle with a preset plurality of base current duty cycles and the target current duty cycles stored in the second memory. If the first target current duty cycle matches a set of target current duty cycles in the second memory, the target current duty cycle and the target pixel grayscale value corresponding to the target current duty cycle can be called at this time, without repeatedly calculating the target pixel grayscale value corresponding to the first target current ratio.

[0199] For ease of understanding, FIG15 is a flow chart of another white balance adjustment method provided in an embodiment of the present application. As shown in FIG15 , the interaction process between the main control device and the projection display device during white balance adjustment includes the following steps.

[0200] S601: The main control device causes the projection display device to enter a white balance debugging mode through the serial port, so that the projection display device projects red, green, blue and white charts in chronological order.

[0201] Among them, the red, green, blue and white charts are test images.

[0202] In one implementation scenario, before performing white balance adjustment, the projection display device may be powered on to start the projection display device. For example, an AC 220V power supply may be provided to the projection display device to power it on.

[0203] S602: The main control device controls the illuminometer to respectively collect the color coordinate values ​​under the red, green and blue charts and the brightness value under the white chart.

[0204] S603: The main control device calculates the target current duty cycle corresponding to the RGBY primary colors according to the acquired color coordinate values ​​and the target color coordinate values ​​based on the automatic white balance algorithm, and sends the target current duty cycle to the projection display device.

[0205] S604: The projection display device compares the target current duty cycle with the pre-stored base current duty cycles corresponding to multiple sets of RGBY primary colors to determine whether a base current duty cycle matches the target current duty cycle. If not, steps S605-S608 are executed; if so, steps S607-S608 are executed.

[0206] S605: The projection display device performs bitplane pixel calibration to determine a target pixel grayscale value corresponding to a target current duty cycle.

[0207] S606: The projection display device writes the grayscale value of the target pixel into the first memory of the digital light processing chip.

[0208] S607: The main control device writes and stores the target current duty ratio corresponding to the RGBY primary colors into the second memory of the micro control unit of the projection display device.

[0209] S608: The main control device calculates target current values ​​corresponding to the RGBY primary colors, and stores the target current values ​​in the second memory of the micro control unit of the projection display device.

[0210] The target current value and the target current duty cycle correspond to an image mode of automatic white balance in the multimedia unit UI.

[0211] During the white balance adjustment process, the processing process of the main control device and the processing process of the projection display device can refer to the above embodiments, and their principles are basically the same, which will not be repeated here in this application.

[0212] To summarize, in the embodiment of the present application, after the projection display device performs white balance adjustment, if it is determined that the target current duty cycle does not match the preset multiple sets of basic current duty cycles, the preset basic pixel grayscale value is not directly called for image display, but the target pixel grayscale value corresponding to the target current duty cycle is determined, thereby avoiding the color cast problem of the grayscale of the image before and after the projection display device performs white balance adjustment, and also making the brightness of the projection display device perceived by the human eye the same before and after the projection display device performs white balance adjustment.

[0213] FIG16 is a schematic diagram of the structure of a white balance adjustment device provided in an embodiment of the present application. The white balance adjustment device may be included in the projection display device provided in an embodiment of the present application. As shown in FIG16 , the white balance adjustment device 1600 includes:

[0214] The color coordinate acquisition module 1601 is used to drive the primary color light sources to emit primary color lights and obtain the first color coordinate value of the white light generated by mixing the primary color lights;

[0215] The white balance adjustment module 1602 is configured to adjust the luminous parameters of the primary color light sources based on the standard color coordinate values ​​when the deviation between the first color coordinate value and the standard color coordinate value is greater than a deviation threshold, so that the deviation between the color coordinate value of the white light generated by the mixture of the primary color lights emitted by the adjusted primary color light sources and the standard color coordinate value is less than or equal to the deviation threshold, and the standard color coordinate value is the white light color coordinate expected to be achieved by the projection display device.

[0216] In one possible implementation, the primary color light sources include a red light source, a green light source, and a blue light source; the primary color lights include red light emitted by the red light source, green light emitted by the green light source, and blue light emitted by the blue light source; and the color coordinate acquisition module 1601 is specifically configured to:

[0217] driving a red light source to emit red light to project a red chart, and obtaining a color coordinate value of the red light based on the projected red chart;

[0218] driving a green light source to emit green light to project a green chart, and obtaining a color coordinate value of the green light based on the projected green chart;

[0219] driving a blue light source to emit blue light to project a blue chart, and obtaining a color coordinate value of the blue light based on the projected blue chart;

[0220] Based on the color coordinate value of the red light, the color coordinate value of the green light, and the color coordinate value of the blue light, a first color coordinate value is determined.

[0221] In one possible implementation, the white balance adjustment module 1602 is specifically configured to:

[0222] Determine the target parameters according to the standard color coordinate values;

[0223] According to the target parameters, the luminous parameters of the primary color light sources are adjusted so that the deviation between the color coordinate value of the white light generated by mixing the primary color lights emitted by the adjusted primary color light sources and the standard color coordinate value is less than or equal to the deviation threshold.

[0224] In one possible implementation, the target parameters include target emission durations of the primary light sources and / or target illuminances of the primary light sources; the primary light sources include red, green, and blue light sources; the primary light sources include red light emitted by a red light source, green light emitted by a green light source, and blue light emitted by a blue light source; and the white balance adjustment module 1602 is specifically configured to:

[0225] Calculate the target parameters using the following formula based on the standard color coordinate value, the color coordinate value of red light, the color coordinate value of green light, and the color coordinate value of blue light;

[0226] Among them, x is the horizontal coordinate of the standard color coordinate value, y is the vertical coordinate of the standard color coordinate value, D r is the target luminous duration of the red light source, D g is the target luminous duration of the green light source, D b Y is the target luminous duration of the blue light source, r is the target illumination of red light, Y g is the target illuminance of green light, Y b is the target illuminance of blue light; x r is the abscissa of the color coordinate value of red light, x g is the abscissa of the color coordinate value of green light, x b is the horizontal coordinate of the color coordinate value of blue light, y r is the ordinate of the color coordinate value of red light, y g The ordinate of the color coordinate value of green light, y b is the ordinate of the color coordinate value of the blue light, C r =Y r / y r , C g =Y g / y g , C b =Y b / y b .

[0227] In one possible implementation, the white balance adjustment module 1602 is specifically configured to:

[0228] The initial luminous duration of the primary color light source is adjusted to the target luminous duration, and / or the initial illuminance of the primary color light is adjusted to the target illuminance, so that the deviation between the coordinate value of the white light generated by the mixture of the primary color lights emitted by the adjusted primary color light source and the standard color coordinate value is less than or equal to the deviation threshold.

[0229] In a possible implementation, the white balance adjustment device 1600 is further configured to:

[0230] The corresponding relationship between the first color coordinate value and the target parameter is stored.

[0231] In a possible implementation, the color coordinate acquisition module 1601 is specifically configured to:

[0232] Get the second color coordinate value of the ambient light;

[0233] Drive the primary color light source to emit primary color light and obtain the third color coordinate value of the mixed light, where the mixed light refers to the light generated by the mixture of ambient light and primary color light;

[0234] The first color coordinate value is determined according to the second color coordinate value and the third color coordinate value.

[0235] In a possible implementation, the white balance adjustment device 1600 is further configured to:

[0236] Receive the target current duty cycle corresponding to the primary color light source sent by the master device, where the target current duty cycle is used to represent the brightness of the primary color light source;

[0237] If the target current duty cycle does not match the base current duty cycle, determining a target pixel grayscale value corresponding to the target current duty cycle;

[0238] According to the target current duty cycle and the target pixel grayscale value, the digital micromirror device is controlled to display the target image.

[0239] In a possible implementation, the white balance adjustment device 1600 is further configured to:

[0240] Receive pixel correction information sent by the main control device, the pixel correction information includes the brightness value of the primary color light source, the frame rate of the input signal corresponding to each primary color light, and the grayscale of the input signal;

[0241] A target pixel grayscale value corresponding to the target current duty cycle is determined according to the pixel correction information.

[0242] In a possible implementation, the white balance adjustment device 1600 is further configured to:

[0243] If the target current duty cycle of each primary color light source included in the target current duty cycle is the same as the basic current duty cycle of the corresponding primary color light source in the basic current duty cycle, or the difference between the target current duty cycle and the basic current duty cycle of the corresponding primary color light source is within an error range, then it is determined that the target current duty cycle matches the basic current duty cycle.

[0244] In a possible implementation, the white balance adjustment device 1600 is further configured to:

[0245] If the target current duty cycle of any primary color light source included in the target current duty cycle is different from the current duty cycle of the corresponding primary color light source in the basic current duty cycle, or the difference between the target current duty cycle and the current duty cycle of the corresponding primary color light source is not within the error range, it is determined that the target current duty cycle does not match the basic current duty cycle.

[0246] In a possible implementation, the white balance adjustment device 1600 is further configured to:

[0247] The target current duty cycle is used as the basic current duty cycle, and the corresponding relationship between the target current duty cycle and the target pixel grayscale value is stored.

[0248] In a possible implementation, the white balance adjustment device 1600 is further configured to:

[0249] receiving a target current value sent by a main control device, where the target current value indicates that the image mode of the projection display device is a white balance mode;

[0250] The correspondence between the target current value and the target current duty cycle is stored.

[0251] In summary, the embodiments of the present application monitor and provide feedback on the current state of white light color coordinates through a processor. When the deviation between a first color coordinate value and a preset standard color coordinate value is detected to be greater than a deviation threshold, a white balance adjustment process is initiated. Based on the standard color coordinate values, the white balance adjustment device adjusts the emission parameters of the primary color light sources to gradually reduce the deviation in the color coordinate values. Through this automatic correction mechanism, the projection display device can ensure that it consistently outputs white light that meets the desired color standard under various operating environments and conditions. Thus, through precise color control and correction, the projection display device can reduce color distortion and deviation, improve image clarity and contrast, and thereby enhance display stability and consistency. Furthermore, because the device can automatically adapt to environmental changes and adjust color parameters, the user does not need to manually perform complex color settings and adjustments, thereby simplifying the operation process and improving ease of use. Furthermore, the automatic adjustment of emission parameters can prevent aging or damage of the light source caused by prolonged operation in non-standard color conditions, thereby helping to extend the service life of the projection display device to a certain extent.

[0252] It should be noted that the white balance adjustment device provided in the above embodiment is merely illustrated by the division of the aforementioned functional modules when performing white balance adjustment on a projection display device. In actual applications, the aforementioned functions can be assigned to different functional modules as needed, i.e., the internal structure of the device can be divided into different functional modules to perform all or part of the functions described above. Furthermore, the white balance adjustment device provided in the above embodiment shares the same concept as the white balance adjustment method embodiments shown in Figures 11 and 14 . The specific implementation process is detailed in the method embodiments and will not be further described here.

[0253] An embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the processor implements the white balance adjustment method described in the embodiment of the present application. The specific implementation method and technical effect are similar and will not be repeated here.

[0254] The computer-readable storage medium may include a USB flash drive, a mobile hard drive, a ROM, a RAM, a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, etc. The computer-readable storage medium may also be a non-volatile storage medium, in other words, a non-transient storage medium.

[0255] It should be understood that all or part of the steps for implementing the above embodiments may be implemented using software, hardware, firmware, or any combination thereof. When implemented using software, all or part of the steps may be implemented in the form of a computer program product. The computer program product may include one or more computer instructions, which may be stored in the above-mentioned computer-readable storage medium.

[0256] That is, the embodiment of the present application also provides a computer program product. When the computer program product runs on a computer, the computer executes the white balance adjustment method described in the embodiment of the present application. The specific implementation method and technical effect are similar and will not be repeated here.

[0257] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the above embodiments, a person skilled in the art can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

[0258] The above description is an embodiment provided for this application and is not intended to limit this application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of this application should be included in the scope of protection of this application.

Claims

1. A projection display device, characterized in that: The projection display device comprises: A primary color light source, used for emitting primary color light; A digital micromirror device, located at the light-emitting side of the primary color light source, for modulating the primary color light and reflecting the modulated light to the projection lens; The projection lens is used to image the light beam emitted by the digital micromirror device; A processor is connected to the digital micromirror device and is used to: driving the primary color light sources to emit primary color lights, and obtaining first color coordinate values ​​of white light generated by mixing the primary color lights; In the case where the deviation between the first color coordinate value and the standard color coordinate value is greater than a deviation threshold, the light-emitting parameters of the primary color light sources are adjusted based on the standard color coordinate value so that the deviation between the color coordinate value of the white light generated by the mixture of the primary color lights emitted by the primary color light sources after the adjustment and the standard color coordinate value is less than or equal to the deviation threshold, and the standard color coordinate value is the white light color coordinate that the projection display device expects to achieve.

2. The projection display device according to claim 1, characterized in that: The primary color light sources include a red light source, a green light source and a blue light source; the primary color light includes red light emitted by the red light source, green light emitted by the green light source and blue light emitted by the blue light source; the processor is specifically used for: driving the red light source to emit red light to project a red chart, and obtaining a color coordinate value of the red light based on the projected red chart; driving the green light source to emit green light to project a green chart, and acquiring a color coordinate value of the green light based on the projected green chart; driving the blue light source to emit blue light to project a blue chart, and acquiring a color coordinate value of the blue light based on the projected blue chart; The first color coordinate value is determined based on the color coordinate value of the red light, the color coordinate value of the green light, and the color coordinate value of the blue light.

3. The projection display device according to claim 1 or 2, characterized in that: The processor is specifically used for: Determining target parameters according to the standard color coordinate values; According to the target parameter, the light emission parameters of the primary color light sources are adjusted so that the deviation between the color coordinate value of the white light generated by mixing the primary color lights emitted by the primary color light sources after the adjustment and the standard color coordinate value is less than or equal to the deviation threshold.

4. The projection display device according to claim 3, characterized in that: The target parameters include the target light emission duration of the primary color light sources and / or the target illumination of the primary color light sources; the primary color light sources include a red light source, a green light source and a blue light source; the primary color light includes red light emitted by the red light source, green light emitted by the green light source and blue light emitted by the blue light source; the processor is specifically used for: Calculate the target parameter by the following formula according to the standard color coordinate value, the color coordinate value of the red light, the color coordinate value of the green light and the color coordinate value of the blue light; Wherein, x is the abscissa of the standard color coordinate value, y is the ordinate of the standard color coordinate value, D r is the target luminous duration of the red light source, D g is the target luminous duration of the green light source, D b is the target luminous duration of the blue light source, Y r is the target illumination of the red light, Y g is the target illumination of the green light, Y b is the target illumination of the blue light; x r is the abscissa of the color coordinate value of the red light, x g is the abscissa of the color coordinate value of the green light, x b is the abscissa of the color coordinate value of the blue light, y r is the ordinate of the color coordinate value of the red light, y g is the ordinate of the color coordinate value of the green light, y b is the ordinate of the color coordinate value of the blue light, C r =Y r / y r , C g =Y g / y g , C b =Y b / y b .

5. The projection display device according to claim 4, characterized in that: The processor is specifically used for: The initial light emission duration of the primary color light source is adjusted to the target light emission duration, and / or the initial illuminance of the primary color light is adjusted to the target illuminance, so that the deviation between the coordinate value of the white light generated by the mixed primary color lights emitted by the primary color light source after the adjustment and the standard color coordinate value is less than or equal to the deviation threshold.

6. The projection display device according to claim 3, characterized in that: The processor is further configured to: The corresponding relationship between the first color coordinate value and the target parameter is stored.

7. The projection display device according to claim 1, characterized in that: The processor is specifically used for: Get the second color coordinate value of the ambient light; driving the primary color light source to emit primary color light, and obtaining a third color coordinate value of mixed light, wherein the mixed light refers to light generated by mixing the ambient light and the primary color light; The first color coordinate value is determined according to the second color coordinate value and the third color coordinate value.

8. The projection display device according to any one of claims 1 to 7, characterized in that: The projection display device is connected to the main control device; after the light emitting parameters of the primary color light sources are adjusted so that the deviation between the color coordinate value of the white light generated by mixing the primary color lights emitted by the primary color light sources after the adjustment and the standard color coordinate value is less than or equal to the deviation threshold, the processor is further used to: receiving a target current duty cycle corresponding to the primary color light source sent by the main control device, where the target current duty cycle is used to represent the brightness of the primary color light source; If the target current duty cycle does not match the base current duty cycle, determining a target pixel grayscale value corresponding to the target current duty cycle; According to the target current duty cycle and the target pixel grayscale value, the digital micromirror device is controlled to display a target image.

9. The projection display device according to claim 8, characterized in that: The processor is specifically used for: Receive pixel correction information sent by the main control device, where the pixel correction information includes the brightness value of the primary color light source, the frame rate of the input signal corresponding to each primary color light, and the grayscale of the input signal; A target pixel grayscale value corresponding to the target current duty cycle is determined according to the pixel correction information.

10. The projection display device according to claim 8 or 9, characterized in that: The processor is further configured to: If the target current duty cycle of each primary color light source included in the target current duty cycle is the same as the basic current duty cycle of the corresponding primary color light source in the basic current duty cycle, or the difference between the target current duty cycle and the basic current duty cycle of the corresponding primary color light source is within an error range, it is determined that the target current duty cycle matches the basic current duty cycle.

11. The projection display device according to claim 8 or 9, characterized in that: The processor is specifically used for: If the target current duty cycle of any primary color light source included in the target current duty cycle is different from the current duty cycle of the corresponding primary color light source in the basic current duty cycle, or the difference between the target current duty cycle and the current duty cycle of the corresponding primary color light source is not within an error range, it is determined that the target current duty cycle does not match the basic current duty cycle.

12. The projection display device according to any one of claims 8 to 11, characterized in that: The processor is further configured to: The target current duty cycle is used as a basic current duty cycle, and a corresponding relationship between the target current duty cycle and the target pixel grayscale value is stored.

13. The projection display device according to any one of claims 8 to 11, characterized in that: The processor is further configured to: receiving a target current value sent by the main control device, wherein the target current value indicates that an image mode of the projection display device is a white balance mode; The corresponding relationship between the target current value and the target current duty cycle is stored.

14. A white balance adjustment method, characterized in that: Applied in a projection display device, the method comprises: driving the primary color light sources to emit primary color lights, and obtaining first color coordinate values ​​of white light generated by mixing the primary color lights; In the case where the deviation between the first color coordinate value and the standard color coordinate value is greater than a deviation threshold, the light-emitting parameters of the primary color light sources are adjusted based on the standard color coordinate value so that the deviation between the color coordinate value of the white light generated by the mixture of the primary color lights emitted by the primary color light sources after the adjustment and the standard color coordinate value is less than or equal to the deviation threshold, and the standard color coordinate value is the white light color coordinate that the projection display device expects to achieve.

15. A white balance adjustment system, characterized in that: The system comprises: a main control device, an illuminometer, and the projection display device according to any one of claims 1 to 13, wherein the main control device is connected to the projection display device and the illuminometer respectively; The main control device is used to control the projection display device to enter a white balance debugging mode so that the projection display device projects multiple test images in chronological order; control the illuminance meter to collect color coordinate values ​​corresponding to the test images, and determine the target current duty ratios corresponding to multiple primary colors constituting the pixel color based on the white balance algorithm and the color coordinate values, and send the target current duty ratio to the projection display device.

16. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method according to claim 14 is implemented.

17. A computer program product comprising instructions, characterized in that When the instructions are executed on a processor, the processor is caused to execute the method of claim 14 .

Images