CN116798365A - Backlight adjusting device for display screen, vehicle-mounted display and infotainment system - Google Patents

Backlight adjusting device for display screen, vehicle-mounted display and infotainment system Download PDF

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Publication number
CN116798365A
CN116798365A CN202310855199.5A CN202310855199A CN116798365A CN 116798365 A CN116798365 A CN 116798365A CN 202310855199 A CN202310855199 A CN 202310855199A CN 116798365 A CN116798365 A CN 116798365A
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CN
China
Prior art keywords
backlight
mode
pin
driving chip
display screen
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Pending
Application number
CN202310855199.5A
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Chinese (zh)
Inventor
吴士鹏
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Continental Automotive Body Electronic System Wuhu Co Ltd
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Continental Automotive Body Electronic System Wuhu Co Ltd
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Application filed by Continental Automotive Body Electronic System Wuhu Co Ltd filed Critical Continental Automotive Body Electronic System Wuhu Co Ltd
Priority to CN202310855199.5A priority Critical patent/CN116798365A/en
Publication of CN116798365A publication Critical patent/CN116798365A/en
Pending legal-status Critical Current

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Classifications

    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
    • G09G3/3406—Control of illumination source
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00—Control of display operating conditions
    • G09G2320/06—Adjustment of display parameters
    • G09G2320/0626—Adjustment of display parameters for control of overall brightness
    • G09G2320/064—Adjustment of display parameters for control of overall brightness by time modulation of the brightness of the illumination source
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00—Control of display operating conditions
    • G09G2320/06—Adjustment of display parameters
    • G09G2320/0626—Adjustment of display parameters for control of overall brightness
    • G09G2320/0653—Controlling or limiting the speed of brightness adjustment of the illumination source
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00—Control of display operating conditions
    • G09G2320/06—Adjustment of display parameters
    • G09G2320/068—Adjustment of display parameters for control of viewing angle adjustment

Abstract

The invention relates to a backlight adjusting device for a display screen, which comprises at least one driving chip, an MCU and a switch assembly, wherein a controlled end of the switch assembly is connected to a first enabling port and a second enabling port, and the MCU is configured to execute the following steps when receiving an input instruction from a user so as to adjust the display screen to a specified backlight mode: respectively adjusting the backlight brightness of the at least one driving chip to a corresponding preset value in a preset step length; and selectively controlling on-off of each switch in the switch assembly to form a corresponding current path between the at least one driving chip and the backlight. The invention also relates to a vehicle-mounted display comprising the backlight adjusting device, and an infotainment system comprising the vehicle-mounted display.

Description

Backlight adjusting device for display screen, vehicle-mounted display and infotainment system
Technical Field
The invention relates to the technical field of electronic display, in particular to a backlight adjusting device for a display screen, a vehicle-mounted display comprising the backlight adjusting device and an infotainment system comprising the vehicle-mounted display.
Background
Electronic displays are widely used as a medium for delivering video information to users in products in various fields including, but not limited to, vehicles, cell phones, computers, watches, etc. In particular, most vehicles are currently equipped with an in-vehicle display, many of which are equipped with a Liquid Crystal Display (LCD). An LCD is a passive display, i.e. it cannot emit light itself, but needs to illuminate the liquid crystal by means of a backlight coupled to the LCD, which is arranged at the back of the LCD.
The backlight brightness of such backlights is typically adjustable by means of a PWM signal (pulse width modulated signal) emitted by the MCU, e.g. the backlight brightness is substantially proportional to the duty cycle of the PWM signal. In particular, during the driving of the vehicle, when the ambient light intensity changes, the MCU will send out a PWM signal with a predetermined duty cycle to adjust the backlight brightness of the vehicle-mounted display accordingly. However, in the conventional backlight brightness adjustment process, the duty ratio of the PWM signal is generally switched from the current value to the target value directly, which may cause a brightness jump phenomenon on the screen of the in-vehicle display.
In addition, the backlight source in the existing vehicle-mounted display can only realize one illumination mode, so that a switching strategy among a plurality of illumination modes does not exist, and different display requirements of a user on the vehicle-mounted display cannot be met by a single illumination mode.
Disclosure of Invention
Aiming at the defects that the existing vehicle-mounted display can not realize the switching among a plurality of illumination modes, is easy to generate brightness jump phenomenon and the like, the invention provides a display screen backlight adjusting device capable of switching the illumination modes. In addition to the conventional public mode, the device adds a private mode and allows the backlighting mode of the display to be switched freely between the two modes. Under this public mode, the user can see what is displayed on the display screen from various angles, as in the backlight mode of a conventional in-vehicle display screen. Under private mode, only a user (e.g., a co-driver position) at a specific angular position can see the content displayed on the display screen, which not only can effectively protect the privacy of the displayed content, but also can prevent the driver from being distracted by not viewing the content of the display screen autonomously, thereby improving driving safety. In addition, by controlling the change curve of the backlight brightness, the phenomena of screen brightness jump, black screen and the like in the mode switching and dimming process can be avoided.
According to a first aspect of the present invention there is provided a backlight adjustment device for a display screen, the device comprising at least one driver chip configured to drive a backlight provided on a rear surface of the display screen and an MCU for adjusting a backlight mode of the at least one driver chip in accordance with an input instruction from a user, wherein,
the apparatus further includes a switching assembly configured to form different current paths between the at least one driving chip and the backlight,
the backlight modes include a first backlight mode and a second backlight mode,
the MCU includes a first enable port and a second enable port corresponding to the first backlight mode and the second backlight mode respectively,
the controlled end of the switch assembly is connected to the first enabling port and the second enabling port so as to form different current paths between the at least one driving chip and the backlight source according to output signals provided by the first enabling port and the second enabling port,
wherein the MCU is configured to perform the following steps upon receiving an input instruction from a user to adjust the display screen to a specified backlight mode:
respectively adjusting the backlight brightness of the at least one driving chip to a corresponding preset value in a preset step length; and
-selectively controlling the switching of the individual switches in the switch assembly to form respective current paths between the at least one driver chip and the backlight.
Advantageously, the MCU is further configured to perform the following steps when an input instruction is received to switch the display screen from the first backlight mode to the second backlight mode:
at a first moment, the backlight brightness of the at least one driving chip is reduced to a set value from a current value by a first step length;
when the backlight brightness of the at least one driving chip reaches the set value, setting the output signal of the second enabling port at a high level at a second moment after the first moment; and
and at a third time after the second time, setting the output signal of the first enabling port to a low level, and increasing the backlight brightness of the at least one driving chip to a target value in a second step length, wherein the third time is separated from the second time by a preset time length.
Advantageously, the at least one driver chip comprises a first driver chip and a second driver chip, the switch assembly comprises first to fourth switches, wherein,
the first switch is connected between the first driving chip and the first enabling port;
the second switch is connected between the first driving chip and the second enabling port;
the third switch is connected between the second driving chip and the first enabling port; and
the fourth switch is connected between the second driving chip and the second enabling port.
Advantageously, each of the first to fourth switches is turned on when a high level signal is received and turned off when a low level signal is received.
Advantageously, the switch assembly further comprises a master switch configured to activate or deactivate the at least one driver chip under control of the MCU.
Advantageously, the MCU further comprises at least one brightness adjustment port connected to the at least one driving chip, and the MCU is further configured to perform the following steps when receiving an input instruction to adjust the display screen to the first backlight mode:
switching on the master control switch to start the at least one driving chip;
placing the output signal of the first enabling port at a high level; and
and outputting a corresponding brightness adjustment signal through the at least one brightness adjustment port to increase the backlight brightness of the at least one driving chip from the current value to the target value.
Advantageously, the first and second fluid-pressure-sensitive devices,
the first backlight mode is a common backlight mode and the second backlight mode is a privacy backlight mode.
Advantageously, the brightness adjustment signal output by the at least one brightness adjustment port is a PWM signal.
According to a second aspect of the present invention, there is also provided an in-vehicle display including:
a display screen;
the backlight source is arranged on the back surface of the display screen to provide corresponding backlight illumination for the display screen; and
a backlight adjustment device as described above for adjusting the illumination of said backlight.
According to a third aspect of the present invention there is also provided an in-vehicle infotainment system comprising:
an in-vehicle display as described above; and
and the vehicle-mounted host is used for providing video signals to be displayed for the vehicle-mounted display.
The backlight adjusting apparatus for a display screen according to the present invention has advantages over conventional backlight adjusting devices including:
-providing two backlighting modes and enabling a free switching between different backlighting modes, thereby ensuring that a suitable lighting mode can be provided for different user needs;
under private mode, only the user at a specific angular position (for example, the co-driver position) can see the content displayed on the display screen, which not only can effectively protect the privacy of the displayed content, but also can prevent the driver from being distracted by not viewing the content of the display screen autonomously, thereby improving driving safety; and
the backlight brightness of the backlight can be adjusted in a gradual and gradual manner, so that the phenomena of screen brightness jump, black screen and the like in the mode switching and brightness adjustment process can be avoided.
Drawings
Other features and advantages of the methods of the present invention will be apparent from, or are apparent from, the accompanying drawings, which are incorporated herein, and the detailed description of the invention, which, together with the drawings, serve to explain certain principles of the invention.
Fig. 1 shows a schematic configuration of a conventional in-vehicle infotainment system.
Fig. 2 illustrates a schematic structure of a backlight adjusting apparatus for a display screen according to an exemplary embodiment of the present invention.
Fig. 3 shows a waveform diagram of a control signal of the backlight adjustment apparatus in fig. 2 under a first control strategy.
Fig. 4 shows a waveform diagram of a control signal of the backlight adjustment apparatus in fig. 2 under a second control strategy.
Detailed Description
A backlight adjusting apparatus for a display screen according to the present invention will be described below by way of example with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention to those skilled in the art. It will be apparent, however, to one skilled in the art that the present invention may be practiced without some of these specific details. Rather, the invention can be considered to be implemented with any combination of the following features and elements, whether or not they relate to different embodiments. Thus, the various aspects, features, embodiments and advantages described below are for illustration only and should not be considered elements or limitations of the claims.
Fig. 1 shows a schematic configuration of a conventional in-vehicle infotainment system. It is assumed that in this in-vehicle infotainment system, for example, an LCD display 10 is used, which needs to be illuminated with a backlight 101 arranged behind the LCD. Thus, in the system, a backlight adjustment device is provided, which can output a corresponding PWM signal to adjust the illumination of the backlight 101, in particular, the backlight brightness of the backlight 101 can be determined based on the PWM signal. For example, the backlight brightness of an in-vehicle display is proportional to the duty cycle of the PWM dimming signal.
In conjunction with illumination by the backlight 101, corresponding video entertainment information may be presented to the user on the display screen 10 based on video display data provided by the in-vehicle host 20. It will be appreciated that prior to providing the video data to the display screen, the raw data from the on-board host 20 needs to be converted and parsed by the deserializer and processed accordingly in an ASIC (application specific integrated circuit, which may be an FPGA for example) for final conversion into a data format that can be received and processed by the display screen.
A CAN bus may be used for communication between the in-vehicle host 20 and the backlight adjustment device so that the backlight adjustment device may receive control instructions, such as input instructions from a user, from the in-vehicle host 20.
In conventional vehicle-mounted displays, only one lighting mode, i.e., public mode (public mode), is generally implemented, in which not only the privacy of the display contents of the display screen cannot be protected, but also distraction of the driver caused by autonomous viewing of the display contents during driving is easily caused. In addition, in the process of directly adjusting the backlight brightness of the vehicle-mounted display by means of the PWM signal, a brightness jump phenomenon occurs in the picture of the vehicle-mounted display, which seriously affects the viewing experience of the user.
In view of the above problems, the present invention provides a display screen backlight adjusting device capable of switching illumination modes. In addition to the conventional public mode, the device adds a private mode and allows the backlighting mode of the display to be switched freely between the two modes. Under this public mode, the user can see what is displayed on the display screen from various angles, as in the backlight mode of a conventional in-vehicle display screen. Under private mode, only a user (e.g., a co-driver position) at a specific angular position can see the content displayed on the display screen, which not only can effectively protect the privacy of the displayed content, but also can prevent the driver from being distracted by not viewing the content of the display screen autonomously, thereby improving driving safety. In addition, by controlling the change curve of the backlight brightness, the phenomena of screen brightness jump, black screen and the like in the mode switching and dimming process can be avoided.
Fig. 2 illustrates a schematic structure of a backlight adjusting apparatus for a display screen according to an exemplary embodiment of the present invention.
As shown in fig. 2, the device may generally include two backlight driving chips and 5 switches to support the backlight to freely switch between public and private modes. When the control signal EN_PUBLIC from the MCU end is enabled, the display screen works in a PUBLIC mode; when the control signal EN_PRIVATE is enabled, the display screen works in the PRIVATE mode, and the display screen can be freely switched in two backlight modes through the MCU control signals EN_PUBLIC and EN_PRIAVTE. The specific structure of the backlight adjusting apparatus will be described in detail with reference to fig. 2.
In addition to the MCU, the device comprises at least one driving chip, here focused on two driving chips, namely a first driving chip IC1 and a second driving chip IC2, each configured to drive a respective portion of the backlight 101 arranged at the back of the display screen 10.
The electrical connection between the driving chips IC1, IC2 and the backlight 101 may be achieved by means of a switching assembly. The on-off of each switch in the switch assembly is controlled by the MCU, so as to establish a corresponding current path according to an INPUT instruction C_INPUT from a user, thereby finally realizing the target backlight driving mode of the driving chips IC1 and IC2. The backlight driving mode may include a first backlight mode (e.g., public mode) and a second backlight mode (e.g., private mode), the at least one driving chip includes a first driving chip IC1 and a second driving chip IC2,
in particular, the MCU may include a first enable port pin_a1 and a second enable port pin_a2 corresponding to the first backlight mode and the second backlight mode, respectively. The controlled end of each switch in the switch assembly is connected to the first enable port pin_a1 or the second enable port pin_a2 of the MCU, respectively, so as to form different current paths between the corresponding driving chips IC1, IC2 and the backlight 101 according to the output signals provided by the first enable port pin_a1 and the second enable port pin_a2.
The MCU may further include a first brightness adjustment port pin_b1 and a second brightness adjustment port pin_b2 connected to the first and second driving chips IC1 and IC2, respectively, whereby the backlight brightness of the backlight 101 may be adjusted by means of PWM signals PWM1, PWM2 output from the brightness adjustment ports of the MCU. By double control of the current path and the backlight brightness, a corresponding backlight mode can be realized.
As shown in fig. 2, the switching assembly may include first to fourth switches SW1 to SW4, and different current paths may be formed between the driving chips IC1, IC2 and the backlight 101 by on-off control of the respective switches.
The first switch SW1 is connected between the first driving chip IC1 and the first enable port pin_a1, the second switch SW2 is connected between the first driving chip IC1 and the second enable port pin_a2, the third switch SW3 is connected between the second driving chip IC2 and the first enable port pin_a1, and the fourth switch SW4 is connected between the second driving chip IC2 and the second enable port pin_a2. Each of the first to fourth switches SW1, SW2, SW3, SW4 is turned on when a high level signal is received and turned off when a low level signal is received.
In addition, the switching assembly may further include a master switch SW0, and the master switch SW0 is configured to activate or deactivate the first and second driving chips IC1 and IC2 under the control of the MCU.
The MCU may receive input instructions from a user (which may be signals of a CAN bus, physical keys in the in-vehicle infotainment system, touch keys, or gesture recognition, etc.), and output corresponding backlight mode enable signals via the enable ports pin_a1, pin_a2 based on the instructions. Where en_public represents the common mode enable signal, en_private represents the privacy mode enable signal, high represents enable/enable, and low represents disable. The backlight brightness is determined by the PWM signals provided by the brightness adjustment ports pin_b1, pin_b2 of the MCU.
In the backlight adjustment apparatus of the present invention, it is assumed that the default mode is the first backlight mode (i.e., the common mode). When the user instruction instructs to make the display screen 10 enter the default mode, the MCU turns on the master control switch SW0 first to start the first driving chip IC1 and the second driving chip IC2; subsequently, the output signal of the first enable port pin_a1 is set to a high level to activate the common mode. In accordance therewith, the backlight luminance of the first driving chip IC1 is increased from the current value to the target value via the first luminance adjustment port pin_b1. Thus, the whole process of enabling the display to enter the default mode is realized.
In addition to the default mode described above, a variety of other control strategies can be implemented by the backlight adjustment device according to the invention, in particular by means of an MCU. Fig. 3 shows a waveform diagram of a control signal of the backlight adjustment apparatus in fig. 2 under a first control strategy.
Referring to fig. 3, when an instruction received from a user instructs to switch the display screen 10 from a first backlight mode (e.g., a public mode) to a second backlight mode (e.g., a private mode), the MCU may sequentially perform the following steps:
-at a first time T1, putting the output signal en_private of the second enable port pin_a2 high; and
-at a second instant T2, the output signal en_pulse of the first enable port pin_a1 is set low, wherein the second instant T2 is after the first instant T1 and spaced from the first instant T1 by a predetermined time period Δt, which may be set to 1m to 5ms, for example. So far, the switching from the public mode to the private mode is completed.
As a result, the current caused by the on of the backlight corresponding to the privacy mode is split, so that the backlight brightness of the backlight corresponding to the public mode is reduced from the current value to the set value from the first time T1, and the backlight brightness of the backlight corresponding to the privacy mode is increased from the current value to the target value. Thus, the user does not feel a significant change in light upon switching between illumination modes in visual effect.
It is contemplated that in another example, as opposed to the embodiment in fig. 3, when an instruction received from a user instructs to switch the display screen 10 from the second backlight mode (e.g., privacy mode) to the first backlight mode (e.g., public mode), the MCU may sequentially perform the following steps:
-at a first time T1, putting the output signal en_pulse of the first enable port pin_a1 high; and
at a second time T2, the output signal en_private of the second enable port pin_a2 is set low, wherein the second time T2 follows the first time T1 and is separated from the first time T1 by a predetermined time period Δt, which may be set to 1m to 5ms, for example. So far, the switching from the privacy mode to the public mode is completed.
As a result, the current is split due to the on of the backlight corresponding to the public mode, so that the backlight brightness of the backlight corresponding to the private mode is reduced from the current value to the lower limit value from the first time T1, and the backlight brightness of the backlight corresponding to the public mode is increased from the current value to the target value.
In the above mode switching process, the backlight brightness finally achieved by the backlight with increased brightness may be equal to the initial backlight brightness value of the backlight with decreased brightness before switching, or may be a backlight brightness target value specifically set for the mode after switching. In the mode switching process, based on the mutual matching between the two enabling signals and the brightness adjusting signal, the black screen phenomenon caused by switching between different modes can be prevented.
Fig. 4 shows a waveform diagram of control signals of the backlight adjustment apparatus in fig. 2 under a second control strategy (also referred to as a "fade-out fade-in control strategy"). The difference from the first control strategy in fig. 3 is that when performing the mode switching, the MCU can adjust the backlight brightness of the driving chips IC1, IC2 from the current value to the corresponding preset value in predetermined steps, for example, in steps of 5% PMW per second, respectively. Such a control strategy is described in detail below with reference to fig. 4.
Referring to fig. 4, c_input represents an input request signal, high level represents a common mode, and low level represents a privacy mode. The input request signal may be from, for example, a signal from a CAN bus of the vehicle, a physical key in the in-vehicle infotainment system, a touch key, gesture recognition, or the like.
PWM represents a backlight luminance value, and 50% PWM in fig. 4 represents a backlight luminance value at the start of switching of the current mode, or a backlight luminance value in another mode at the end of switching, which may be set to any one of the minimum PWM value to the 100% PWM value. The 10% PWM value represents the minimum PWM value, which can be customized according to the actual situation, and can be obtained from the EEPROM in the MCU.
During brightness adjustment, the fade-out step size (i.e., the amount of PMW adjusted per second) or number of steps (e.g., the total number of steps stepped down from 50% pwm to 10% pwm) and the fade-in step size or number of steps (e.g., the total number of steps stepped up from 10% pwm to 50% pwm) may be set to be the same as or different from each other, and the start and end values of fade-out and fade-in may also be the same as or different from each other. In general, the step size/number can be customized or adjusted according to the actual situation, and can be obtained from EEPROM.
When the c_input signal goes from high to low, indicating that the user desires to switch the display screen 10 from a first backlight mode (e.g., a public mode) to a second backlight mode (e.g., a private mode), the MCU may then sequentially perform the following steps:
-at a first time T1, reducing the backlight brightness of the driving chips IC1, IC2 from the current value (e.g. 50% pwm) to the set value (e.g. 10% pwm) in a first step;
when the backlight brightness of the driving chips IC1, IC2 reaches the set value, the output signal en_private of the second enable port is set to high level at a second time T2 after the first time T1; and
-at a third instant T3, the output signal of the first enable port is put at a low level en_pulse and the backlight brightness of the driving chips IC1, IC2 is increased to a target value (e.g. 50% pwm) in a second step, wherein the third instant T3 is after the second instant T2 and spaced from the second instant T2 by a predetermined time period Δt, which Δt may be set to 1m to 5ms, for example. So far, the switching from the public mode to the private mode is completed.
It is contemplated that in another example, as opposed to the embodiment in fig. 4, when the c_input signal goes from low to high, indicating that the user desires to switch the display screen 10 from the second backlight mode (e.g., privacy mode) to the first backlight mode (e.g., public mode), at which point the MCU may sequentially perform the following steps:
-at a first time T1, reducing the backlight brightness of the driving chips IC1, IC2 from the current value (e.g. 50% pwm) to the set value (e.g. 10% pwm) in a first step;
-when the backlight brightness of the driving chips IC1, IC2 reaches the set value, the output signal en_pulse of the first enable port is set high at the second instant T2; and
-at a third instant T3, the output signal of the second enable port is put at a low level en_privateand the backlight brightness of the driving chips IC1, IC2 is increased to a target value (e.g. 50% pwm) in a second step, wherein the third instant T3 is after the second instant T2 and spaced from the second instant T2 by a predetermined time period Δt, which Δt may be set to 1m to 5ms, for example. So far, the switching from the privacy mode to the public mode is completed.
In the above mode switching process, the backlight luminance (i.e., 50% pwm) that the backlight with increased luminance finally reaches may be equal to the initial backlight luminance value of the backlight with reduced luminance before switching, or may be a backlight luminance target value specifically set for the mode after switching. In the mode switching process, based on the mutual coordination between the two enabling signals and the brightness adjusting signals, the free switching between the two modes can be completed in a gradually-coming-in mode, and the black screen phenomenon caused by the switching between different modes can be prevented.
The backlight adjusting apparatus for a display screen according to the present invention has advantages over conventional backlight adjusting devices including:
-providing two backlighting modes and enabling a free switching between different backlighting modes, thereby ensuring that a suitable lighting mode can be provided for different user needs;
under private mode, only the user at a specific angular position (for example, the co-driver position) can see the content displayed on the display screen, which not only can effectively protect the privacy of the displayed content, but also can prevent the driver from being distracted by not viewing the content of the display screen autonomously, thereby improving driving safety; and
the backlight brightness of the backlight can be adjusted in a gradual and gradual manner, so that the phenomena of screen brightness jump, black screen and the like in the mode switching and brightness adjustment process can be avoided.
It will be appreciated by a person skilled in the art that the individual steps of the method according to the invention are not limited to being carried out in the order listed above. While the invention has been described in terms of preferred embodiments, the invention is not limited thereto. Any person skilled in the art shall not depart from the spirit and scope of the present invention and shall accordingly fall within the scope of the invention as defined by the appended claims.

Claims (10)

1. Backlight adjustment device for a display screen (10), the device comprising at least one driver chip (IC 1, IC 2) configured to drive a backlight (101) arranged at the back of the display screen (10), and an MCU for adjusting the backlight mode of the at least one driver chip (IC 1, IC 2) in accordance with an INPUT instruction (c_input) from a user,
the device further comprises a switching assembly configured to form different current paths between the at least one driver chip (IC 1, IC 2) and the backlight (101),
the backlight modes include a first backlight mode and a second backlight mode,
the MCU includes a first enable port (PIN A1) and a second enable port (PIN A2) corresponding to the first backlight mode and the second backlight mode respectively,
the controlled end of the switch assembly is connected to the first enabling port (PIN_A1) and the second enabling port (PIN_A2) so as to form different current paths between the at least one driving chip (IC 1, IC 2) and the backlight source (101) according to output signals provided by the first enabling port (PIN_A1) and the second enabling port (PIN_A2),
wherein the MCU is configured to perform the following steps upon receiving an input instruction from a user to adjust the display screen (10) to a specified backlight mode:
-adjusting the backlight brightness of the at least one driving chip (IC 1, IC 2) to respective preset values in predetermined steps, respectively; and
-selectively controlling the switching of the individual switches in the switching assembly to form respective current paths between the at least one driver chip (IC 1, IC 2) and the backlight (101).
2. A backlight adjustment device according to claim 1, characterized in that the MCU is further configured to perform the following steps when receiving an input instruction to switch the display screen (10) from the first backlight mode to the second backlight mode:
at a first instant (T1), reducing the backlight brightness of the at least one driving chip (IC 1, IC 2) from a current value to a set value in a first step size;
when the backlight brightness of the at least one driving chip (IC 1, IC 2) reaches the set value, the output signal of the second enabling port is set to a high level at a second time (T2) after the first time (T1); and
-at a third time (T3) after the second time (T2), placing the output signal of the first enable port at a low level, and increasing the backlight brightness of the at least one driving chip (IC 1, IC 2) to a target value in a second step, wherein the third time (T3) is spaced from the second time (T2) by a predetermined time period (Δt).
3. A backlight adjustment device according to claim 2, characterized in that the at least one driving chip comprises a first driving chip (IC 1) and a second driving chip (IC 2), the switch assembly comprises first to fourth switches (SW 1, SW2, SW3, SW 4), wherein,
a first switch (SW 1) connected between the first driving chip (IC 1) and the first enable port (pin_a1);
a second switch (SW 2) connected between the first driving chip (IC 1) and the second enable port (pin_a2);
a third switch (SW 3) connected between the second driving chip (IC 2) and the first enable port (pin_a1); and
the fourth switch (SW 4) is connected between the second driving chip (IC 2) and the second enable port (pin_a2).
4. A backlight adjusting device according to claim 3, wherein each of the first to fourth switches (SW 1, SW2, SW3, SW 4) is turned on when receiving a high level signal and turned off when receiving a low level signal.
5. A backlight adjustment device according to any one of claims 1 to 4, characterized in that the switch assembly further comprises a master switch (SW 0), the master switch (SW 0) being configured to activate or deactivate the at least one driver chip (IC 1, IC 2) under control of the MCU.
6. A backlight adjustment device according to claim 5, characterized in that the MCU further comprises at least one brightness adjustment port (pin_b1, pin_b2) connected to the at least one driving chip (IC 1, IC 2), and in that the MCU is further configured to perform the following steps when receiving an input instruction to adjust the display screen (10) to the first backlight mode:
turning on the master switch (SW 0) to activate the at least one driver chip (IC 1, IC 2);
placing the output signal of the first enable port (pin_a1) at a high level; and
a corresponding brightness adjustment signal is output via the at least one brightness adjustment port (pin_b1, pin_b2) to increase the backlight brightness of the at least one driving chip (IC 1, IC 2) from a current value to a target value.
7. The backlight adjusting apparatus according to any one of claims 1 to 4, wherein,
the first backlight mode is a common backlight mode and the second backlight mode is a privacy backlight mode.
8. A backlight adjustment device according to claim 6, characterized in that the brightness adjustment signal output by the at least one brightness adjustment port (pin_b1, pin_b2) is a PWM signal.
9. A vehicle-mounted display, characterized in that the vehicle-mounted display comprises:
a display screen (10);
a backlight (101), the backlight (101) being arranged at the back of the display screen (10) to provide corresponding backlighting to the display screen (10); and
a backlight adjustment device according to any one of claims 1 to 8, for adjusting the illumination of the backlight (101).
10. A vehicle infotainment system, the system comprising:
the in-vehicle display of claim 9; and
and the vehicle-mounted host machine (20) is used for providing video signals to be displayed for the vehicle-mounted display.
CN202310855199.5A 2023-07-12 2023-07-12 Backlight adjusting device for display screen, vehicle-mounted display and infotainment system Pending CN116798365A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202310855199.5A CN116798365A (en) 2023-07-12 2023-07-12 Backlight adjusting device for display screen, vehicle-mounted display and infotainment system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202310855199.5A CN116798365A (en) 2023-07-12 2023-07-12 Backlight adjusting device for display screen, vehicle-mounted display and infotainment system

Publications (1)

Publication Number Publication Date
CN116798365A true CN116798365A (en) 2023-09-22

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ID=88034449

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202310855199.5A Pending CN116798365A (en) 2023-07-12 2023-07-12 Backlight adjusting device for display screen, vehicle-mounted display and infotainment system

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Country Link
CN (1) CN116798365A (en)

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