Medical dfstn liquid crystal display screen gray scale driving correction method and system

Abstract

The present application belongs to the technical field of liquid crystal display driving control, and discloses a medical DFSTN liquid crystal display screen gray scale driving correction method and system, which comprises the following steps: acquiring display data and calibration files, dividing gray scale correction units and determining basic gray scale response relationship; selecting passive reference pixels and determining current display offset; determining effective driving code interval and brightness interval; dividing medical display objects and obtaining object gray scale constraint groups; determining unified target brightness and eliminating gray scale resource conflicts; determining regional output driving code and establishing a gray scale driving correction mapping table; and checking and correcting the mapping table according to actual display brightness. The present application realizes differentiated allocation of medical DFSTN liquid crystal display screen gray scale driving resources and local closed-loop correction in the normal display process.

Description

Technical Field

[0001] This invention belongs to the field of liquid crystal display driving control technology, specifically relating to a grayscale driving correction method and system for a medical DFSTN liquid crystal display screen. Background Technology

[0002] With the increasing demands for display clarity in medical monitors, portable diagnostic devices, and in vitro diagnostic equipment, DFSTN liquid crystal displays have gained popularity due to their low power consumption, stable operation, and wide environmental adaptability. These displays employ a dual-compensation super-twisted nematic liquid crystal structure. Their grayscale brightness is affected not only by the output drive code but also by differences in the compensation structure, display position, and operating temperature. The same input grayscale value may exhibit different brightness levels in different display areas, and adjacent grayscale levels in dark areas are prone to compression, making it difficult to distinguish local levels of vital signs, physiological change curves, and alarm indicators.

[0003] Current grayscale calibration methods typically employ a uniform grayscale mapping table across the entire screen, or fix drive parameters after displaying a dedicated test screen at the factory. These methods struggle to reflect regional brightness shifts that occur during device operation and cannot differentiate grayscale resources based on different medical display content. When the same medical display object spans multiple display areas with varying optical responses, the same output drive code may cause boundary brightness jumps. Furthermore, re-performing dedicated screen calibration occupies normal display time, making it unsuitable for devices requiring continuous presentation of medical data. Summary of the Invention

[0004] This invention provides a grayscale driving correction method and system for medical DFSTN liquid crystal displays, solving the technical problems in the background art.

[0005] This invention provides a grayscale driving correction method for a medical DFSTN liquid crystal display screen, comprising the following steps:

[0006] The system acquires the input grayscale value, medical display object identifier, display area identifier, current temperature, and preset DFSTN grayscale calibration file. It then divides the grayscale correction units according to the display area identifier and determines the current basic grayscale response relationship.

[0007] Passive reference pixels are selected from the normal medical display content, and the current display offset of each gray level correction unit is determined based on the actual display brightness and the current basic gray level response relationship.

[0008] Based on the current display offset and the preset DFSTN grayscale calibration file, determine the current effective driving code range and the current effective brightness range of each grayscale correction unit;

[0009] Medical display objects are divided according to the medical display object identifier and pixel adjacency relationship. The object level, minimum adjacent gray level distinguishable interval and object gray level sequence are determined to obtain the object gray level constraint group.

[0010] Based on the current effective brightness range corresponding to the grayscale correction unit spanned by the medical display object, the unified target brightness at the object level is determined, and grayscale resource conflicts are resolved according to the object grayscale constraint group and object level to obtain the grayscale resource allocation result.

[0011] Based on the unified target brightness at the object level, the grayscale resource allocation results, and the current effective driving code range, the regional output driving code is determined and a grayscale driving correction mapping table is established.

[0012] The grayscale driving correction mapping table is written into the display control unit, and local verification and correction are performed based on the actual display brightness to obtain the updated grayscale driving correction mapping table.

[0013] The present invention also provides a grayscale driving correction system for a medical DFSTN liquid crystal display screen, comprising:

[0014] The basic response module is used to acquire input grayscale values, medical display object identifiers, display area identifiers, current temperature, and preset DFSTN grayscale calibration files. It divides grayscale correction units according to the display area identifiers and determines the current basic grayscale response relationship.

[0015] The display offset module is used to select passive reference pixels from the normal medical display content and determine the current display offset of each gray level correction unit based on the actual display brightness and the current basic gray level response relationship.

[0016] The effective range module is used to determine the current effective driving code range and the current effective brightness range of each grayscale correction unit based on the current display offset and the preset DFSTN grayscale calibration file.

[0017] The object constraint module is used to divide medical display objects according to medical display object identifiers and pixel adjacency relationships, determine object level, minimum adjacent gray level distinguishable interval and object gray level sequence, and obtain object gray level constraint group;

[0018] The resource allocation module is used to determine the unified target brightness at the object level based on the current effective brightness range corresponding to the grayscale correction unit spanned by the medical display object, and to resolve grayscale resource conflicts based on the object grayscale constraint group and object level to obtain the grayscale resource allocation result.

[0019] The mapping generation module is used to determine the regional output driving code and establish a grayscale driving correction mapping table based on the object-level unified target brightness, grayscale resource allocation results and the current effective driving code range.

[0020] The local correction module is used to write the grayscale driving correction mapping table into the display control unit, and perform local verification and correction based on the actual display brightness to obtain an updated grayscale driving correction mapping table.

[0021] The beneficial effects of this invention are as follows: This invention establishes the current basic grayscale response relationship based on the regional optical differences of the DFSTN liquid crystal display screen and the current temperature, and selects passive reference pixels from normal medical display content to determine the current display offset of each grayscale correction unit, without the need to insert a dedicated grayscale test screen. The actual grayscale driving capability of each region is limited by the current effective driving code range and the current effective brightness range. Grayscale resources are then allocated according to the object level of the medical display object and the minimum distinguishable interval between adjacent grayscale levels, ensuring high grayscale distinguishability for alarm indicators, key vital signs values, and physiological change curves. By unifying the target brightness at the object level and outputting driving codes in different regions, brightness jumps when the same medical display object crosses regions are reduced. Through local verification and directional correction, only mapping items that do not meet the conditions are updated, reducing the impact of full table recalculation on the normal display process and suppressing grayscale compression, abnormal grayscale order, and increased brightness in dark background states. Attached Figure Description

[0022] Figure 1 This is a flowchart of a grayscale driving correction method for a medical DFSTN liquid crystal display screen according to the present invention;

[0023] Figure 2 This is a schematic diagram of grayscale resource allocation provided in an embodiment of the present invention;

[0024] Figure 3 This is a partial verification flowchart provided in an embodiment of the present invention;

[0025] Figure 4 This is a schematic diagram of the structure of a medical DFSTN liquid crystal display grayscale driving correction system according to the present invention. Detailed Implementation

[0026] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described are only used to illustrate the technical solutions of the present invention, and are not intended to limit the scope of protection of the present invention. Those skilled in the art can adjust some technical features, processing order or module connection relationship according to actual application needs without departing from the concept of the present invention, and can also combine related technical features in different embodiments. All technical solutions formed should fall within the protection scope of the present invention.

[0027] It should be noted that, unless otherwise expressly defined, the technical terms used in this specification should be interpreted according to their common understanding by those skilled in the art. The terms "first," "second," etc., used in this specification are only used to distinguish corresponding technical objects and do not indicate a fixed order, quantitative relationship, or degree of importance between the stated technical objects. Terms such as "include" and "comprising" indicate that, in addition to the technical features, steps, or modules listed subsequently, other technical features, steps, or modules may also be included. The term "connection" in this specification includes direct connections and indirect connections, and may represent spatial connection relationships, data transmission relationships, or function call relationships.

[0028] like Figure 1 As shown, a grayscale driving correction method for a medical DFSTN liquid crystal display screen includes the following steps:

[0029] The system acquires the input grayscale value, medical display object identifier, display area identifier, current temperature, and preset DFSTN grayscale calibration file. It then divides the grayscale correction units according to the display area identifier and determines the current basic grayscale response relationship.

[0030] Passive reference pixels are selected from the normal medical display content, and the current display offset of each gray level correction unit is determined based on the actual display brightness and the current basic gray level response relationship.

[0031] Based on the current display offset and the preset DFSTN grayscale calibration file, determine the current effective driving code range and the current effective brightness range of each grayscale correction unit;

[0032] Medical display objects are divided according to the medical display object identifier and pixel adjacency relationship. The object level, minimum adjacent gray level distinguishable interval and object gray level sequence are determined to obtain the object gray level constraint group.

[0033] Based on the current effective brightness range corresponding to the grayscale correction unit spanned by the medical display object, the unified target brightness at the object level is determined, and grayscale resource conflicts are resolved according to the object grayscale constraint group and object level to obtain the grayscale resource allocation result.

[0034] Based on the unified target brightness at the object level, the grayscale resource allocation results, and the current effective driving code range, the regional output driving code is determined and a grayscale driving correction mapping table is established.

[0035] The grayscale driving correction mapping table is written into the display control unit, and local verification and correction are performed based on the actual display brightness to obtain the updated grayscale driving correction mapping table.

[0036] In one embodiment of the present invention, the input grayscale value, medical display object identifier, display area identifier, current temperature, and preset DFSTN grayscale calibration file are acquired. Grayscale correction units are divided according to the display area identifier, and the current basic grayscale response relationship is determined. The DFSTN liquid crystal display screen employs a dual-compensated super-twisted nematic liquid crystal structure. The input grayscale value represents the brightness level allocated to each pixel position by the display control unit. The medical display object identifier is synchronously associated with the pixel position and is used to distinguish alarm identifiers, key vital sign values, physiological change curves, ordinary text, and display background. The display area identifier characterizes the physical display area to which the pixel belongs in the DFSTN liquid crystal display screen. The current temperature is the liquid crystal operating temperature when the corresponding display area performs this grayscale driving correction.

[0037] When generating normal medical display content, the display rendering layer of the medical device simultaneously outputs the input grayscale value and medical display object identifier corresponding to each pixel position. The display control unit queries the corresponding display area identifier based on the pixel coordinates. The current temperature is collected by temperature detection units located on the back or edge of the DFSTN LCD screen. When multiple temperature detection units are set, the value collected by the temperature detection unit closest to the corresponding display area is taken as the current temperature of that display area according to the spatial distance between each temperature detection unit and the display area. This establishes a correspondence between the input grayscale value, medical display object identifier, display area identifier, and current temperature according to pixel position.

[0038] A preset DFSTN grayscale calibration profile is created before the DFSTN LCD screen is put into normal display. Specifically, it involves performing grayscale display calibration on different display areas at multiple calibration temperatures and saving the corresponding calibration results. The preset DFSTN grayscale calibration profile includes the target brightness of the input grayscale at each calibration temperature, the basic front-view brightness, the preset side-view calibration brightness, the basic output drive code, the allowed range of output drive codes, the allowable brightness deviation, the upper limit of dark-state brightness, and the lowest adjacent grayscale brightness difference. The target brightness of the input grayscale serves as the target brightness reference for each input grayscale, the basic front-view brightness is the brightness reference obtained from the front-view direction of the display screen, and the preset side-view calibration brightness is the brightness reference obtained from a preset side-view position.

[0039] The basic output drive code records the LCD drive parameter encoding corresponding to the input grayscale under the calibration state. The allowed output drive code range limits the upper and lower boundaries of the drive code that can be used for the corresponding input grayscale. The brightness allowable deviation limits the allowable deviation range of the actual brightness relative to the target brightness of the input grayscale. The dark state brightness upper limit limits the highest brightness that the lowest input grayscale can reach. The lowest adjacent grayscale brightness difference limits the minimum brightness difference required for adjacent input grayscales to remain distinguishable.

[0040] The pixel positions are grouped according to the display area identifier, and grayscale correction units are divided based on the regional optical consistency results in the preset DFSTN grayscale calibration file. A grayscale correction unit consists of pixels with similar and spatially continuous grayscale electro-optical responses. Within the same grayscale correction unit, the difference in basic frontal brightness corresponding to the same input grayscale does not exceed a preset unit brightness difference threshold, and the arrangement order of the basic frontal brightness corresponding to each input grayscale remains consistent. During division, the display area can first be divided into multiple continuous pixel blocks according to a preset size, and then the basic frontal brightness of adjacent pixel blocks at each input grayscale can be compared. When adjacent pixel blocks meet the brightness difference and brightness arrangement order conditions, they are merged into the same grayscale correction unit.

[0041] For example, the display area can be initially divided into eight rows and eight columns of pixel blocks. When the difference in basic frontal brightness between adjacent pixel blocks under each input grayscale does not exceed 3%, the corresponding pixel blocks are merged.

[0042] After determining the grayscale correction unit, the two adjacent calibration temperatures of the current temperature are found from the preset DFSTN grayscale calibration file. These two calibration temperatures are located on the lower and higher temperature sides of the current temperature, respectively, and are the calibration temperatures closest to the current temperature on their respective temperature sides. The difference between the current temperature and the lower calibration temperature is compared with the temperature interval obtained by subtracting the lower calibration temperature from the higher calibration temperature to obtain the positional ratio of the current temperature between the two calibration temperatures. According to this positional ratio, the input grayscale target brightness, basic frontal brightness, preset side-view calibration brightness, basic output drive code, allowed output drive code range, brightness allowable deviation, dark state brightness upper limit, and lowest adjacent grayscale brightness difference corresponding to the two calibration temperatures are weighted to form the current basic grayscale response relationship of each grayscale correction unit at the current temperature.

[0043] For example, if two adjacent calibration temperatures are 20 degrees Celsius and 40 degrees Celsius, and the current temperature is 30 degrees Celsius, the current temperature is in the middle of the two. The calibration data corresponding to the two calibration temperatures are combined with a weight of 0.5.

[0044] When the current temperature is lower than the lowest calibration temperature in the preset DFSTN grayscale calibration file, or higher than the highest calibration temperature, the calculation is no longer extended beyond the calibration temperature range. Instead, the distance between the current temperature and each boundary calibration temperature is compared, and the calibration data corresponding to the calibration temperature closest to the current temperature is used as the current basic grayscale response relationship. The resulting current basic grayscale response relationship retains the correspondence between the grayscale correction unit, the input grayscale value, and the current temperature, and serves as the basis for subsequently determining the current display offset and filtering the current effective drive code range and the current effective brightness range. This ensures that subsequent grayscale drive correction is based on the actual optical response conditions of each display area at the current temperature.

[0045] In one embodiment of the present invention, a passive reference pixel is selected from the normal medical display content. Based on the actual display brightness and the current basic grayscale response relationship, the current display offset corresponding to each input grayscale value in each grayscale correction unit is determined. The actual display brightness is the brightness value actually presented at the corresponding pixel position of the DFSTN liquid crystal display under the current temperature and current driving state, which can be obtained by a brightness acquisition unit set in the front viewing direction of the display screen. The brightness acquisition unit can be an image acquisition device with a fixed acquisition position and fixed exposure parameters, or it can be a brightness detection device set corresponding to the grayscale correction unit. The acquisition results are associated with the normal medical display content according to the pixel position, display area identifier, and acquisition time.

[0046] During normal display of the medical equipment, the actual display brightness corresponding to each pixel position is read, and the corresponding baseline viewing brightness is read from the current baseline grayscale response relationship based on the grayscale correction unit to which each pixel position belongs and the corresponding input grayscale value. To reduce brightness acquisition mismatch caused by changes in display content, the acquisition time of the actual display brightness and the reading time of the input grayscale value are correlated using the same display update flag, so that the actual display brightness and the baseline viewing brightness participating in the comparison correspond to the same pixel position and the same input grayscale value.

[0047] Furthermore, passive reference pixels are selected from the normal medical display content. Passive reference pixels refer to brightness reference pixels selected directly from the current display content without altering the normal medical display content or inserting dedicated grayscale test images. A pixel is identified as a candidate passive reference pixel if it maintains the same input grayscale value across multiple consecutive display update times, and the medical display object is identified as ordinary text or display background, and is not located at the boundary of the display object, the edge of character strokes, the boundary of the display area, or a state transition area. The preferred number of consecutive display update times is five display update times. "Input grayscale value remains unchanged" means that the input grayscale value of the candidate pixel is the same throughout the specified display update times.

[0048] The display object boundary is the location where the medical display object identifier changes among adjacent pixels; the character stroke edge is the location where the character stroke in ordinary text is adjacent to the display background; the display area boundary is the location where the display area identifier changes among adjacent pixels; and the state transition area is the area where the medical display content switches between different display contents according to a preset state. The actual display brightness at the above locations is easily affected by edge blending, differences in area response, or content switching, and therefore is not used as passive reference pixels. Furthermore, locations within 1 to 2 pixels of the display object boundary, character stroke edge, or display area boundary can be excluded.

[0049] The reference brightness deviation is calculated for each passive reference pixel. The specific calculation process is as follows: the actual display brightness of the passive reference pixel is subtracted from the corresponding base viewing brightness to obtain the reference brightness difference; the corresponding base viewing brightness is added to a preset minimum positive value to obtain the brightness reference correction value; and the reference brightness difference is divided by the brightness reference correction value to obtain the reference brightness deviation.

[0050] The reference brightness deviation can be expressed as: ,in, Indicates a passive reference pixel The corresponding reference brightness deviation, Indicates a passive reference pixel The actual display brightness Indicates a passive reference pixel The grayscale correction unit to which it belongs. Indicates a passive reference pixel The corresponding input grayscale value, Indicates grayscale correction unit Input grayscale value The corresponding baseline viewing brightness, This represents a preset minimum positive value. This is a pre-set minimum positive number to prevent invalid calculations when the base viewing brightness corresponding to the lowest input grayscale is zero or close to zero. A preferred value is 0.001, or one ten-thousandth of the minimum effective value of the base viewing brightness. A reference brightness deviation greater than zero indicates that the actual display brightness is higher than the base viewing brightness; a reference brightness deviation less than zero indicates that the actual display brightness is lower than the base viewing brightness.

[0051] The reference brightness deviation of each passive reference pixel is collected according to the grayscale correction unit and the input grayscale value. For passive reference pixels with the same input grayscale value within the same grayscale correction unit, the corresponding reference brightness deviations are arranged in ascending order of value; when the number is odd, the middle value is taken as the current display offset; when the number is even, the average of the two middle values ​​is taken as the current display offset. The obtained current display offset corresponds to the grayscale correction unit and the input grayscale value, and is used to characterize the brightness shift of the corresponding area and the corresponding input grayscale value relative to the current basic grayscale response relationship, and to reduce the influence of local reflections, acquisition noise, and individual abnormal pixels on the offset result.

[0052] The number of effective passive reference pixels corresponding to the same input grayscale value within the same grayscale correction unit is verified, and a preset minimum number of references is set, preferably 8. When the number of effective passive reference pixels is less than the preset minimum number of references, the input grayscale values ​​that have formed the current display offset are searched within the same grayscale correction unit in ascending order of the numerical difference between the input grayscale values, and the current display offset corresponding to the nearest input grayscale value is adopted; when the numerical distance between the input grayscale values ​​on both sides and the current input grayscale value is the same, the average value of the current display offsets on both sides is taken.

[0053] If no input grayscale value with a current display offset has been generated within the same grayscale correction unit, the most recently saved current display offset of that grayscale correction unit is used. If no historical current display offset exists, the current display offset is set to zero, and a reference data insufficiency flag is generated. The obtained current display offset, together with the preset DFSTN grayscale calibration file, is used for the brightness correction of subsequent candidate output drive codes and for determining the current effective drive code range and the current effective brightness range.

[0054] In one embodiment of the present invention, based on the current display offset and a preset DFSTN grayscale calibration file, the current effective driving code range and the current effective brightness range corresponding to each input grayscale value in each grayscale correction unit are determined. The current effective driving code range is a continuous output driving code range that can simultaneously satisfy brightness accuracy, grayscale arrangement order, adjacent grayscale distinguishability, and dark state limitation under the current temperature and actual display offset conditions. The current effective brightness range is the corrected display brightness range in the frontal viewing direction corresponding to the current effective driving code range.

[0055] For each grayscale correction unit and each input grayscale value, the allowed output drive code range and the calibrated brightness of each candidate output drive code within the allowed output drive code range under the frontal and preset side viewing directions are read from the preset DFSTN grayscale calibration file. The candidate output drive codes are the output drive codes to be verified within the allowed output drive code range, and each candidate output drive code corresponds to a set of defined liquid crystal driving parameter codes.

[0056] The calibration brightness corresponding to each candidate output driver code is corrected based on the current display offset. The specific calculation process is as follows: the current display offset is added to 1 to obtain the display offset correction coefficient; then, the calibration brightness of the candidate output driver code in the corresponding viewing direction is multiplied by the display offset correction coefficient to obtain the corrected display brightness of the candidate output driver code in the corresponding viewing direction.

[0057] The corrected display brightness can be expressed as: ,in, Indicates grayscale correction unit Input grayscale value Using candidate output driving codes At that time, in the direction of observation Correcting the display brightness below, Indicates grayscale correction unit At the current temperature The following uses candidate output driving code At that time, in the direction of observation The calibrated brightness is below. This indicates the frontal view or any preset side view. Indicates the candidate output driver code, Indicates grayscale correction unit The corresponding current temperature, Indicates grayscale correction unit Input grayscale value The corresponding current display offset. The corrected display brightness represents the expected display brightness generated by the candidate output driver code after considering the current actual display offset. When the current display offset is positive, the corrected display brightness is higher than the corresponding calibrated brightness; when the current display offset is negative, the corrected display brightness is lower than the corresponding calibrated brightness.

[0058] Within the allowed range of output driving codes, candidate output driving codes are verified in ascending order of their size. First, the corrected display brightness corresponding to the candidate output driving code in the frontal view direction is compared with the target brightness of the input grayscale, and the absolute value of the difference between the two is taken. If the absolute value of the difference is not greater than the corresponding allowable brightness deviation, the candidate output driving code is retained for subsequent verification.

[0059] For candidate output drive codes that pass the brightness tolerance check, the brightness arrangement order is checked under both the frontal viewing direction and each preset side viewing direction. When the current input grayscale is neither the lowest nor the highest input grayscale, its corrected display brightness is no lower than the base brightness corresponding to the previous input grayscale and no higher than the base brightness corresponding to the next input grayscale; when the current input grayscale is the lowest input grayscale, only its corrected display brightness is checked to be no higher than the base brightness corresponding to the next input grayscale; when the current input grayscale is the highest input grayscale, only its corrected display brightness is checked to be no lower than the base brightness corresponding to the previous input grayscale. Each base brightness is read from the current base grayscale response relationship according to the corresponding viewing direction.

[0060] Simultaneously, the brightness difference between adjacent input gray levels is verified. For non-lowest input gray levels, the corrected display brightness in the viewing direction corresponding to the current input gray level using the current candidate output driving code is subtracted from the corrected display brightness in the viewing direction corresponding to the previous input gray level using its basic output driving code. When the resulting difference is not less than the brightness difference of the lowest adjacent gray level, the condition for distinguishable adjacent gray levels is determined to be met. For the lowest input gray level, the aforementioned adjacent gray level difference verification is not performed. Instead, its corrected display brightness in the viewing direction is compared with the upper limit of dark state brightness to ensure that the corrected display brightness of the lowest input gray level does not exceed the upper limit of dark state brightness.

[0061] Candidate output driving codes that simultaneously meet the requirements of luminance tolerance, luminance arrangement order, minimum adjacent grayscale luminance difference, and upper limit of dark state luminance are combined into a valid candidate driving code set. The absolute value of the numerical difference between each candidate output driving code in the valid candidate driving code set and the base output driving code is calculated, and the candidate output driving code with the smallest absolute value of numerical difference is determined as the center driving code; if there are multiple candidate output driving codes with the same absolute value of numerical difference, the one with the smaller value is selected.

[0062] After obtaining the center driving code, the set of valid candidate driving codes is segmented according to whether the output driving code values ​​are continuous. The longest driving code segment containing the center driving code and with consecutive adjacent output driving codes is determined as the current valid driving code interval. The display brightness corresponding to each candidate output driving code in this interval is read to correct the frontal direction, and the minimum and maximum values ​​are determined as the lower and upper limits of the current valid brightness interval, respectively, so that the subsequent object-level unified target brightness is limited to the brightness range that the corresponding grayscale correction unit can actually achieve.

[0063] If no candidate output driving code satisfies all screening criteria, the corrected display brightness in the forward viewing direction corresponding to the basic output driving code is read. This corrected display brightness is used as both the lower and upper limits of the current effective brightness range. Simultaneously, a grayscale driving range insufficiency marker is generated, and the corresponding grayscale correction unit and input grayscale value are recorded. The resulting current effective driving code range and current effective brightness range serve as the constraint basis for subsequent object-level unified target brightness determination and grayscale resource allocation.

[0064] In one embodiment of the present invention, medical display objects are classified according to medical display object identifiers and pixel adjacency relationships, and the object level, minimum distinguishable adjacent grayscale interval, and object grayscale sequence corresponding to each medical display object are further determined to form an object grayscale constraint group. Medical display objects consist of pixels of the same object category that are spatially continuous; the object level is used to determine the processing order of different medical display objects when participating in subsequent grayscale resource allocation; the minimum distinguishable adjacent grayscale interval is used to limit the minimum brightness difference that should be maintained between the target brightness corresponding to adjacent input grayscale values ​​within the same medical display object.

[0065] The medical display object identifier corresponding to each pixel position is read, and pixel adjacency relationships are established based on pixel coordinates. Two pixels sharing a pixel boundary in the horizontal or vertical direction are identified as adjacent pixels; pixels that only touch in a diagonal direction are not established as adjacent. Starting from pixels that have not yet been grouped, adjacent pixels with the same medical display object identifier are continuously searched, and the same search is performed on newly grouped pixels until no more adjacent pixels of the same type can be grouped. The resulting continuous set of pixels is identified as a medical display object. Pixels with the same medical display object identifier but spatially separated form different medical display objects to ensure that the object partitioning result is consistent with the actual display position.

[0066] After obtaining the medical display object, its object level is determined from high to low according to the following order: alarm identifier, key vital sign values, physiological change curve, ordinary text, and display background. In one embodiment, it can be set sequentially as object level 5, object level 4, object level 3, object level 2, and object level 1. The object level remains unchanged during the same grayscale driving correction process and serves as the basis for the processing order among different medical display objects in the event of subsequent grayscale resource conflicts.

[0067] The highest and lowest target brightness of the display screen are read based on the current basic grayscale response relationship, and the basic adjacent grayscale brightness difference is determined by combining this with the total number of input grayscale levels. Specifically, the difference between the highest and lowest target brightness of the display screen is taken as the target brightness range, and then the target brightness range is divided by the value obtained by subtracting one from the total number of input grayscale levels to obtain the basic adjacent grayscale brightness difference. The highest target brightness of the display screen corresponds to the input grayscale target brightness of the highest input grayscale value, and the lowest target brightness of the display screen corresponds to the input grayscale target brightness of the lowest input grayscale value.

[0068] Each object level is associated with a corresponding grayscale discernibility coefficient, and the grayscale discernibility coefficient increases with the object level. The grayscale discernibility coefficients for object levels 1 to 5 can be set to 1, 1.15, 1.30, 1.45, and 1.60 respectively. The minimum adjacent grayscale discernibility interval for the medical display object is obtained by multiplying the basic adjacent grayscale brightness difference by the grayscale discernibility coefficient corresponding to that object. For example, when the basic adjacent grayscale brightness difference is 1 candela per square meter, the minimum adjacent grayscale discernibility interval for ordinary text is 1.15 candela per square meter, and the minimum adjacent grayscale discernibility interval for alarm signs is 1.60 candela per square meter. The grayscale discernibility coefficients are pre-configured based on the grayscale calibration results of the DFSTN LCD screen and remain fixed during this grayscale driving correction process.

[0069] The actual input grayscale values ​​used by the pixels contained in each medical display object are statistically analyzed. After removing duplicate values, the grayscale values ​​are arranged in ascending order to obtain the object grayscale sequence. A correspondence is established between the object grayscale sequence, the object level, and the minimum distinguishable interval between adjacent grayscale levels to form the object grayscale constraint group for that medical display object. Each object grayscale constraint group corresponds to one medical display object and serves as constraint data for subsequently determining the unified target brightness at the object level and resolving grayscale resource conflicts. This allows different medical display objects to be allocated corresponding grayscale driving resources according to the object level and grayscale distinguishability requirements.

[0070] In one embodiment of the present invention, a uniform target brightness at the object level is determined based on the current effective brightness range corresponding to the grayscale correction units traversed by the medical display object. Grayscale resource conflicts are then resolved according to the object's grayscale constraint group and object level to obtain the grayscale resource allocation result. The uniform target brightness at the object level is the brightness target commonly used by the same input grayscale value of the same medical display object in different grayscale correction units.

[0071] like Figure 2 As shown, when a medical display object spans multiple grayscale correction units, the common brightness range at the object level is determined based on the current effective brightness range of each correction unit, and grayscale resources are allocated in conjunction with the object grayscale constraint group, thereby determining the output driving code corresponding to each region.

[0072] Based on the grayscale correction units corresponding to the pixels contained in the medical display object, the set of grayscale correction units spanned by the medical display object is determined. For each input grayscale value in the object's grayscale sequence, the current effective brightness range corresponding to each grayscale correction unit in the set is read. When the medical display object is located in only one grayscale correction unit, the current effective brightness range corresponding to that grayscale correction unit is directly used.

[0073] For the same input grayscale value of the same medical display object, the maximum value among the lower limits of each current effective brightness range is determined as the common lower limit of the object level, and the minimum value among the upper limits of each current effective brightness range is determined as the common upper limit of the object level. The two together represent the brightness range that the input grayscale value can be achieved in all relevant grayscale correction units.

[0074] When the lower limit of the object-level common brightness is not greater than the upper limit of the object-level common brightness, the input grayscale target brightness is limited to between the two. If it is lower than the lower limit, the lower limit is used; if it is higher than the upper limit, the upper limit is used; if it is in between, it remains unchanged. The resulting brightness is the unified target brightness at the object level. When the lower limit of the object-level common brightness is greater than the upper limit, the two are added together and divided by 2 to obtain the unified target brightness at the object level, and a cross-region grayscale capability insufficiency marker is generated. The cross-region grayscale capability insufficiency marker records the corresponding medical display object, input grayscale value, and grayscale correction unit.

[0075] Further, the grayscale sequence of the objects is verified in ascending order of the input grayscale values. The object-level unified target brightness of the next input grayscale value is subtracted from the object-level unified target brightness of the previous input grayscale value to obtain the brightness difference between adjacent targets. When the brightness difference between adjacent targets is less than the minimum distinguishable interval between adjacent grayscale values, the object-level unified target brightness of the previous input grayscale value is added to the minimum distinguishable interval between adjacent grayscale values ​​to obtain the corrected target brightness of the next input grayscale value. When the corrected target brightness does not exceed the upper limit of the common brightness of the object level, it is determined as the new object-level unified target brightness; when it exceeds the upper limit of the common brightness of the object level, a brightness interval insufficiency mark is generated. The brightness interval insufficiency mark indicates that the corresponding adjacent input grayscale values ​​cannot meet the minimum distinguishable interval between adjacent grayscale values ​​within the current common brightness range.

[0076] Based on the adjusted object-level unified target brightness, the candidate output driver code with the smallest difference between the corrected display brightness and the object-level unified target brightness is selected within the current valid driver code range, and grayscale resource conflicts are detected. Grayscale resource conflicts include candidate output driver code overlap, insufficient brightness interval, abnormal brightness order, and excessive dark-state brightness. Candidate output driver code overlap occurs when different input grayscale values ​​correspond to the same candidate output driver code; abnormal brightness order occurs when the achievable brightness of a higher input grayscale value is not higher than that of a lower input grayscale value; and excessive dark-state brightness occurs when the lowest input grayscale value corresponding to the display background exceeds the upper limit of dark-state brightness.

[0077] When a grayscale resource conflict occurs, grayscale resources are released from the lowest object level to the highest object level, following the order of display background, ordinary text, physiological change curves, key vital sign values, and alarm indicators. The object-level unified target brightness difference between each pair of adjacent input grayscale values ​​in the current low-object-level medical display object is compared. The pair with the smallest brightness difference is selected and merged into the same grayscale resource position, ensuring that the brightness of the higher input grayscale value is not lower than that of the lower input grayscale value. The grayscale resource position corresponds to the allocation position of the candidate output driving code and its achievable brightness. After each merging, the object-level unified target brightness and candidate output driving code of the affected medical display object are re-determined until the grayscale resource conflict is resolved.

[0078] When grayscale resource conflicts still exist after processing all merging lower-level adjacent input grayscale values, the minimum distinguishable interval between adjacent grayscale values ​​of higher-level medical display objects is maintained, the number of available grayscale values ​​for lower-level medical display objects is reduced, and a grayscale resource insufficiency marker is generated. Finally, the adjusted object-level unified target brightness, the merging relationship of adjacent input grayscale values, the cross-regional grayscale capability insufficiency marker, the brightness interval insufficiency marker, and the grayscale resource insufficiency marker are collectively determined as the grayscale resource allocation result.

[0079] Through the above processing, the same medical display object maintains a uniform brightness target in different grayscale correction units, and prioritizes the grayscale discernibility of alarm indicators, key vital signs values ​​and physiological change curves when grayscale resources are limited, thereby reducing grayscale compression in dark areas, brightness jumps across regions and abnormal grayscale order.

[0080] In one embodiment of the present invention, a region output driving code is determined and a grayscale driving correction mapping table is established based on the object-level unified target brightness, grayscale resource allocation results, and the currently valid driving code range. The region output driving code is a liquid crystal driving parameter encoding determined for a specific grayscale correction unit, medical display object, and input grayscale value, and includes at least the COM scan voltage code, SEG data voltage code, number of subframes illuminated, and subframe illumination position.

[0081] For unmerged input grayscale values ​​in the grayscale resource allocation results, as well as input grayscale values ​​merged into the same grayscale resource position, their corresponding object-level unified target brightness and current effective drive code range are read. Based on the current display offset and the preset DFSTN grayscale calibration file, the corrected display brightness corresponding to each candidate output drive code within the current effective drive code range is determined. The specific calculation process is as follows: the current display offset is added to 1 to obtain the display offset correction coefficient, and then the front-view calibration brightness corresponding to the candidate output drive code is multiplied by the display offset correction coefficient to obtain the corresponding corrected display brightness.

[0082] For each candidate output driver code, the corrected display brightness is subtracted from the object-level uniform target brightness, and the absolute value of the difference is taken to obtain the target brightness deviation. Candidate output driver codes are then filtered in ascending order of target brightness deviation, and it is verified whether the corrected display brightness corresponding to the candidate output driver code conforms to the brightness arrangement order of the object's grayscale sequence. The candidate output driver code with the smallest target brightness deviation and conforming to the brightness arrangement order is determined as the region output driver code. The brightness arrangement order means that the corrected display brightness corresponding to a higher input grayscale value is not lower than the corrected display brightness corresponding to a lower input grayscale value.

[0083] When multiple candidate output driving codes have the same target brightness deviation, first calculate the absolute value of the difference between each candidate output driving code and the base output driving code, and select the candidate output driving code with the smallest absolute value of the difference. If multiple candidate output driving codes still exist, select the candidate output driving code with the smaller value. If they still cannot be distinguished, select the candidate output driving code used by the corresponding joint index in the most recent grayscale driving correction mapping table. If no historical records exist, retain the candidate output driving code with the smaller value.

[0084] After determining the output drive code for the region, the corresponding positive and negative polarity subframes are read. A positive polarity subframe is a display period where the driving voltage at both ends of the pixel is positive, and a negative polarity subframe is a display period where the driving voltage at both ends of the pixel is opposite to that of the positive polarity subframe. Within a correction cycle, the effective driving voltage corresponding to each positive polarity subframe is multiplied by its corresponding effective duration, and the products are accumulated to obtain the cumulative positive effective voltage. Similarly, the absolute value of the effective driving voltage corresponding to each negative polarity subframe is multiplied by its corresponding effective duration, and the products are accumulated to obtain the cumulative negative effective voltage. The absolute value of the difference between the cumulative positive and negative effective voltages is determined as the cumulative polarity loss.

[0085] The cumulative polarity loss can be expressed as: ,in, This represents the cumulative polarity loss within a correction period. This represents the set of positive polarity subframes within a correction period. This represents the set of negative polarity subframes within a correction period. Indicates the first The effective driving voltage corresponding to each positive polarity subframe Indicates the first The effective driving voltage corresponding to each negative polarity subframe Indicates the first The effective duration of a positive polarity subframe Indicates the first The effective duration of each negative polarity subframe. The cumulative polarity loss measure represents the cumulative difference between positive and negative driving forces within one correction period.

[0086] When the cumulative polarity imbalance exceeds the preset polarity imbalance threshold, while maintaining the number of lit subframes and the unified target brightness at the object level, the polarity allocation, effective driving voltage, or effective duration of the positive and negative polarity subframes are adjusted, and the settings of the positive and negative polarity subframes are rearranged until the cumulative polarity imbalance does not exceed the preset polarity imbalance threshold. The preset polarity imbalance threshold is preferably 1% to 5% of the average of the cumulative positive and negative effective voltages. After the adjustment is completed, the corrected display brightness corresponding to the regional output driving code is recalculated, and the brightness arrangement order of the object grayscale sequence is verified. When the corrected display brightness does not meet the unified target brightness or brightness arrangement order at the object level, a candidate output driving code that simultaneously meets the target brightness deviation, brightness arrangement order, and preset polarity imbalance threshold is selected from the current effective driving code range.

[0087] Furthermore, using the grayscale correction unit identifier, the medical display object identifier, and the input grayscale value as a joint index, the corresponding region output driving code is written into the grayscale driving correction mapping table. For multiple input grayscale values ​​merged into the same grayscale resource location in the grayscale resource allocation result, the same region output driving code is written into the corresponding joint index.

[0088] Furthermore, when a medical display object with an object level higher than ordinary text crosses the boundary of the grayscale correction unit, the corrected display brightness corresponding to the output driving code of the regions on both sides of the boundary is read respectively, and the absolute value of the difference between the two is determined as the boundary brightness difference. When the boundary brightness difference is greater than a preset boundary brightness difference threshold, a transition region is established in the pixels belonging to ordinary text or display background outside the medical display object. The preset boundary brightness difference threshold is preferably 3% to 8% of the corresponding object-level uniform target brightness, and the width of the transition region is preferably 1 to 3 pixels.

[0089] For each pixel in the transition region, the distance from that pixel to the boundary of the highest-level medical display object is divided by the sum of the width of the transition region and 1 to obtain the distance ratio. The output drive code of the region closer to the highest-level medical display object is multiplied by 1 and then subtracted from the distance ratio. The original output drive code of the outermost lower-level medical display object is multiplied by the distance ratio. The two products are then added together and the nearest integer is taken to obtain the output drive code of the transition region.

[0090] The distance ratio can be expressed as: The numerical driving parameters can be expressed as: round ,in, Represents pixels in the transition region The corresponding distance ratio, Represents pixels in the transition region The pixel distance to the boundary of the highest object level medical display object. Indicates the pixel width of the transition region. Represents pixels in the transition region The corresponding numerical driving parameters, This indicates the corresponding numerical driving parameter on the side closer to the high-level medical display object. This refers to the original numerical driving parameters of the peripheral low-level medical display object, where "round" indicates taking the nearest valid integer from the calculation result. The numerical driving parameters include COM scan voltage code, SEG data voltage code, or the number of subframes illuminated. The transition region is only set within the peripheral low-level medical display object and does not change the region output driving code within the alarm indicator, key vital sign values, and physiological change curves.

[0091] In one embodiment of the present invention, a grayscale driving correction mapping table is written into the display control unit, and local verification and correction are performed based on the actual display brightness to obtain an updated grayscale driving correction mapping table. For example... Figure 3 As shown, after the grayscale driving correction mapping table is written to the display control unit, the actual display brightness is collected and locally verified during normal display. If the verification conditions are not met, the corresponding area output driving code is re-determined, and the grayscale driving correction mapping table is updated. Specifically, the grayscale driving correction mapping table is written to the mapping storage area of ​​the display control unit. When the display control unit receives normal medical display content, it determines the grayscale correction unit identifier according to the pixel position, reads the corresponding medical display object identifier and input grayscale value, and uses the grayscale correction unit identifier, medical display object identifier, and input grayscale value as a joint index to query the area output driving code, and drives the DFSTN liquid crystal display screen according to the area output driving code.

[0092] During normal medical display, passive reference pixels are selected according to the aforementioned screening criteria, and the current display offset corresponding to each input grayscale value in each grayscale correction unit is updated. Simultaneously, within each medical display object, pixels whose input grayscale values ​​remain unchanged, are not located at the boundaries of the display object or the edges of character strokes, and whose actual display brightness can be effectively read are selected, and their corresponding actual display brightness is collected. Each actual display brightness is aggregated according to the medical display object, input grayscale value, and grayscale correction unit, and a correspondence is established with the unified target brightness at the object level.

[0093] For the same medical display object, the same input grayscale value, and the same grayscale correction unit, the actual display brightness of each pixel is subtracted from the object-level unified target brightness, and the absolute value is taken. All absolute values ​​are then sorted in ascending order, and the median value is taken as the object brightness deviation; when the number of deviations is even, the average of the two median values ​​is taken. The object brightness deviation represents the degree of deviation between the actual display brightness of the corresponding local mapping item and the object-level unified target brightness. Further, the median value of the difference between the actual display brightness of each pixel and the object-level unified target brightness is determined as the brightness direction deviation. A brightness direction deviation greater than zero indicates that the actual display is too bright, and less than zero indicates that the actual display is too dark.

[0094] For the same medical display object, the median actual display brightness value corresponding to each input grayscale value in the object's grayscale sequence is calculated. Arranged in ascending order of input grayscale values, the median actual display brightness value of each subsequent input grayscale value is subtracted from the median actual display brightness value of the preceding input grayscale value to obtain the brightness difference between adjacent input grayscale values. The minimum of these subtractions is determined as the actual minimum adjacent grayscale brightness difference. This check is not performed if the object's grayscale sequence contains only one input grayscale value. For the display background, the effective pixel corresponding to the lowest input grayscale value is selected, and its median actual display brightness value is determined as the actual dark state brightness of the display background.

[0095] The object brightness deviation is compared with a preset object brightness deviation threshold, the actual minimum adjacent grayscale brightness difference is compared with the corresponding minimum adjacent grayscale discernible interval, and the actual dark state brightness of the displayed background is compared with the upper limit of dark state brightness. The preset object brightness deviation threshold is the maximum allowable deviation of the local mapping item relative to the object-level uniform target brightness, preferably 2% to 5% of the object-level uniform target brightness.

[0096] When the object brightness deviation exceeds the preset object brightness deviation threshold, the brightness direction deviation is subtracted from the unified target brightness at the object level to obtain the locally corrected target brightness. Within the corresponding currently valid drive code range, a candidate output drive code with the smallest difference between the corrected display brightness and the locally corrected target brightness, and conforming to the brightness arrangement order, is reselected. When the actual minimum adjacent grayscale brightness difference is less than the minimum distinguishable interval between adjacent grayscale levels, if two mapping items with interval conflicts belong to different medical display objects, the mapping item with the lower object level is adjusted first; if they belong to the same medical display object, the mapping item farther from the basic output drive code is adjusted; if the distance is the same, the corrected display brightness corresponding to the higher input grayscale value is increased. When the actual dark state brightness of the display background exceeds the upper limit of dark state brightness, within the corresponding currently valid drive code range, a candidate output drive code whose corrected display brightness does not exceed the upper limit of dark state brightness and is closest to the original area output drive code is selected.

[0097] After reselection, the brightness arrangement order and polarity balance of the output drive code in the corresponding area are re-verified. Only the output drive code of the area corresponding to the medical display object, input grayscale value and grayscale correction unit that does not meet the verification conditions is replaced. The other mapping items remain unchanged, and the updated grayscale drive correction mapping table is obtained. The corresponding current temperature, current display offset and verification results are saved.

[0098] Through the above processing, local mapping terms that have brightness deviation, insufficient grayscale interval, or dark state enhancement can be directionally corrected during normal medical display, so as to maintain the grayscale discernibility of key medical display objects and the consistency of cross-region display.

[0099] In one embodiment of the present invention, such as Figure 4 As shown, it also includes a grayscale driving correction system for a medical DFSTN liquid crystal display screen, comprising:

[0100] The basic response module is used to acquire input grayscale values, medical display object identifiers, display area identifiers, current temperature, and preset DFSTN grayscale calibration files. It divides grayscale correction units according to the display area identifiers and determines the current basic grayscale response relationship.

[0101] The display offset module is used to select passive reference pixels from the normal medical display content and determine the current display offset of each gray level correction unit based on the actual display brightness and the current basic gray level response relationship.

[0102] The effective range module is used to determine the current effective driving code range and the current effective brightness range of each grayscale correction unit based on the current display offset and the preset DFSTN grayscale calibration file.

[0103] The object constraint module is used to divide medical display objects according to medical display object identifiers and pixel adjacency relationships, determine object level, minimum adjacent gray level distinguishable interval and object gray level sequence, and obtain object gray level constraint group;

[0104] The resource allocation module is used to determine the unified target brightness at the object level based on the current effective brightness range corresponding to the grayscale correction unit spanned by the medical display object, and to resolve grayscale resource conflicts based on the object grayscale constraint group and object level to obtain the grayscale resource allocation result.

[0105] The mapping generation module is used to determine the regional output driving code and establish a grayscale driving correction mapping table based on the object-level unified target brightness, grayscale resource allocation results and the current effective driving code range.

[0106] The local correction module is used to write the grayscale driving correction mapping table into the display control unit, and perform local verification and correction based on the actual display brightness to obtain an updated grayscale driving correction mapping table.

[0107] The embodiments of the present invention have been described above. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms based on the guidance of the present embodiments, all of which are within the protection scope of the present embodiments.

Claims

1. A grayscale driving correction method for a medical DFSTN liquid crystal display screen, characterized in that, Includes the following steps: The system acquires the input grayscale value, medical display object identifier, display area identifier, current temperature, and preset DFSTN grayscale calibration file. It then divides the grayscale correction units according to the display area identifier and determines the current basic grayscale response relationship. Passive reference pixels are selected from the normal medical display content, and the current display offset of each gray level correction unit is determined based on the actual display brightness and the current basic gray level response relationship. Based on the current display offset and the preset DFSTN grayscale calibration file, determine the current effective driving code range and the current effective brightness range of each grayscale correction unit; Medical display objects are divided according to the medical display object identifier and pixel adjacency relationship. The object level, minimum adjacent gray level distinguishable interval and object gray level sequence are determined to obtain the object gray level constraint group. Based on the current effective brightness range corresponding to the grayscale correction unit spanned by the medical display object, the unified target brightness at the object level is determined, and grayscale resource conflicts are resolved according to the object grayscale constraint group and object level to obtain the grayscale resource allocation result. Based on the unified target brightness at the object level, the grayscale resource allocation results, and the current effective driving code range, the regional output driving code is determined and a grayscale driving correction mapping table is established. The grayscale driving correction mapping table is written into the display control unit, and local verification and correction are performed based on the actual display brightness to obtain the updated grayscale driving correction mapping table.

2. The grayscale driving correction method for a medical DFSTN liquid crystal display screen according to claim 1, characterized in that, The system acquires the input grayscale value, medical display object identifier, display area identifier, current temperature, and preset DFSTN grayscale calibration profile. Based on the display area identifier, it divides the grayscale correction units and determines the current basic grayscale response relationship, including: Acquire the input grayscale value, medical display object identifier, display area identifier, and current temperature; and read the preset DFSTN grayscale calibration file. The preset DFSTN grayscale calibration file includes the target brightness of the input grayscale at each calibration temperature, the basic frontal brightness, the preset side-view calibration brightness, the basic output drive code, the allowed range of the output drive code, the allowable brightness deviation, the upper limit of the dark state brightness, and the lowest adjacent grayscale brightness difference. Grayscale correction units are divided according to the optical consistency of each display area, and two calibration temperatures adjacent to the current temperature are determined; Based on the position ratio of the current temperature between the two calibration temperatures, the calibration data corresponding to the two calibration temperatures are weighted respectively to obtain the current basic grayscale response relationship; When the current temperature exceeds the calibrated temperature range, the calibration data corresponding to the calibrated temperature closest to the current temperature will be determined as the current basic grayscale response relationship.

3. The grayscale driving correction method for a medical DFSTN liquid crystal display screen according to claim 1, characterized in that, Passive reference pixels are selected from the normal medical display content. Based on the actual display brightness and the current basic grayscale response relationship, the current display offset of each grayscale correction unit is determined, including: Read the actual display brightness of each pixel in the normal medical display content, and read the basic viewing brightness corresponding to each input gray level value from the current basic gray level response relationship; Pixels whose input grayscale value remains constant, belong to ordinary text or display background and are not located at the boundary of the display object, the edge of character strokes, the boundary of the display area, or the state alternation area are defined as passive reference pixels; The difference between the actual displayed brightness and the corresponding baseline viewing brightness is divided by the sum of the baseline viewing brightness and the preset minimum positive value to obtain the reference brightness deviation. The median value of the reference brightness deviation corresponding to the same input gray level value within the same gray level correction unit is determined as the current display offset. When there are insufficient effective passive reference pixels, the current display offset within the same grayscale correction unit is selected from the nearest to the farthest distance of the input grayscale value; if no such offset exists, the most recent current display offset or zero value is used in sequence, and a reference data shortage mark is generated.

4. The grayscale driving correction method for a medical DFSTN liquid crystal display screen according to claim 1, characterized in that, Based on the current display offset and the preset DFSTN grayscale calibration file, determine the current effective drive code range and the current effective brightness range for each grayscale correction unit, including: The corrected display brightness is obtained by adjusting the calibrated brightness of each candidate output driver code in the frontal and preset side viewing directions based on the current display offset. Within the allowed range of output drive codes, candidate output drive codes are selected and corrected to meet the brightness allowable deviation of the input grayscale target brightness, the brightness arrangement order in the front viewing direction and the preset side viewing direction, the lowest adjacent grayscale brightness difference, and the upper limit of dark state brightness. The candidate output driving codes that meet the screening criteria are combined into a set of valid candidate driving codes, and the candidate output driving code that is closest to the basic output driving code is determined as the center driving code. The longest continuous driving code segment containing the center driving code is determined as the current effective driving code interval, and the minimum and maximum values ​​of the corrected display brightness within this interval are determined as the lower and upper limits of the current effective brightness interval. When no valid candidate driving code exists, the corrected display brightness corresponding to the basic output driving code is simultaneously determined as the lower and upper limits of the current valid brightness range, and a grayscale driving range insufficient marker is generated.

5. The grayscale driving correction method for a medical DFSTN liquid crystal display screen according to claim 1, characterized in that, Medical display objects are segmented based on their identifiers and pixel adjacency relationships. The object level, minimum distinguishable interval between adjacent gray levels, and object gray level sequence are determined, resulting in an object gray level constraint group, including: Based on the medical display object identifier and pixel adjacency relationship, pixels with the same object category and spatial contiguousness are merged into a medical display object; The object level is determined from high to low according to the order of alarm sign, key vital sign values, physiological change curve, plain text and display background; Divide the difference between the highest and lowest target brightness of the display screen by the difference between the total number of input grayscale levels and one to obtain the basic adjacent grayscale brightness difference. Configure grayscale discernibility coefficients that increase with the increase of object level for each object level, and determine the minimum adjacent grayscale discernibility interval by multiplying the brightness difference between basic adjacent grayscale levels and the corresponding grayscale discernibility coefficient. The actual input grayscale values ​​used by each medical display object are arranged in ascending order to obtain the object grayscale sequence, and then combined with the object level and the smallest distinguishable interval between adjacent grayscale levels to form an object grayscale constraint group.

6. The grayscale driving correction method for a medical DFSTN liquid crystal display screen according to claim 1, characterized in that, Based on the current effective brightness range corresponding to the grayscale correction units spanned by the medical display object, a unified target brightness at the object level is determined. Then, grayscale resource conflicts are resolved according to the object's grayscale constraint group and object level to obtain the grayscale resource allocation result, including: Determine the grayscale correction units that each medical display object traverses, and read the current effective brightness range corresponding to each input grayscale value in the object's grayscale sequence; The maximum value among the lower limits of the current effective brightness range of each grayscale correction unit is determined as the lower limit of the common brightness at the object level, and the minimum value among the upper limits is determined as the upper limit of the common brightness at the object level. When the lower limit of the common brightness of the object level is not greater than the upper limit of the common brightness of the object level, the target brightness of the input grayscale is limited to between the two to obtain the unified target brightness of the object level; otherwise, the average value of the two is determined as the unified target brightness of the object level, and a marker indicating insufficient cross-region grayscale capability is generated. The object grayscale sequence is verified based on the smallest distinguishable interval between adjacent grayscale levels, and the unified target brightness of the object corresponding to the higher input grayscale value is increased within the range not exceeding the upper limit of the common brightness of the object level. The system detects overlapping candidate output driving codes, insufficient brightness intervals, abnormal brightness order, and excessive dark-state brightness. It then merges adjacent input grayscale values ​​of low-level medical display objects according to their object level from low to high and redetermines the unified target brightness at the object level to obtain the grayscale resource allocation result.

7. The grayscale driving correction method for a medical DFSTN liquid crystal display screen according to claim 1, characterized in that, Based on the unified target brightness at the object level, grayscale resource allocation results, and the current valid drive code range, the regional output drive code is determined and a grayscale drive correction mapping table is established, including: Based on the current display offset and the preset DFSTN grayscale calibration file, determine the corrected display brightness corresponding to each candidate output drive code within the current valid drive code range; The candidate output driver code with the smallest difference between the corrected display brightness and the unified target brightness at the object level, and which conforms to the brightness ranking order, is determined as the region output driver code; when the differences are the same, the candidate output driver code that is closest to the basic output driver code, has the smaller value, or is the most recently used candidate output driver code is selected in sequence. Based on the difference in effective driving amount between the positive and negative polarity subframes corresponding to the regional output driving code, the cumulative polarity imbalance is determined, the subframe driving configuration is adjusted so that the cumulative polarity imbalance does not exceed the preset polarity imbalance threshold, and the brightness arrangement order is re-verified. Using the grayscale correction unit identifier, medical display object identifier, and input grayscale value as a joint index, the region output driving code is written into the grayscale driving correction mapping table; When a medical display object with an object level higher than ordinary text crosses the boundary of a grayscale correction unit and the boundary brightness difference is greater than a preset boundary brightness difference threshold, the output driving code of the regions on both sides of the boundary is weighted according to the distance from the pixel to the object boundary within the medical display object of lower object level outside it, and the output driving code of the transition region is obtained.

8. The grayscale driving correction method for a medical DFSTN liquid crystal display screen according to claim 1, characterized in that, The grayscale drive correction mapping table is written into the display control unit, and local verification and correction are performed based on the actual display brightness to obtain an updated grayscale drive correction mapping table, including: Write the grayscale drive correction mapping table into the display control unit, output the drive code according to the grayscale correction unit identifier, medical display object identifier and input grayscale value query area, and drive the DFSTN LCD screen. During normal medical display, passive reference pixels are selected to collect the actual display brightness of each medical display object and the display background. The median absolute difference between the actual display brightness and the unified target brightness at the object level is determined as the object brightness deviation, and the minimum value among the differences in the median values ​​of the actual display brightness corresponding to adjacent input grayscale values ​​is determined as the actual minimum adjacent grayscale brightness difference. The median value of the actual display brightness of the background pixels is determined as the actual dark state brightness of the display background; when the object brightness deviation exceeds the limit, the actual minimum adjacent gray level brightness difference is insufficient, or the actual dark state brightness of the display background exceeds the limit, the region output driving code is re-determined according to the corresponding threshold. Only update the medical display objects that do not meet the verification conditions, the input grayscale values, and the corresponding area output drive codes of the grayscale correction units to obtain the updated grayscale drive correction mapping table.

9. A grayscale driving correction system for a medical DFSTN liquid crystal display screen, characterized in that, A grayscale driving correction method for a medical DFSTN liquid crystal display screen as described in any one of claims 1-8, comprising: The basic response module is used to acquire input grayscale values, medical display object identifiers, display area identifiers, current temperature, and preset DFSTN grayscale calibration files. It divides grayscale correction units according to the display area identifiers and determines the current basic grayscale response relationship. The display offset module is used to select passive reference pixels from the normal medical display content and determine the current display offset of each gray level correction unit based on the actual display brightness and the current basic gray level response relationship. The effective range module is used to determine the current effective driving code range and the current effective brightness range of each grayscale correction unit based on the current display offset and the preset DFSTN grayscale calibration file. The object constraint module is used to divide medical display objects according to medical display object identifiers and pixel adjacency relationships, determine object level, minimum adjacent gray level distinguishable interval and object gray level sequence, and obtain object gray level constraint group; The resource allocation module is used to determine the unified target brightness at the object level based on the current effective brightness range corresponding to the grayscale correction unit spanned by the medical display object, and to resolve grayscale resource conflicts based on the object grayscale constraint group and object level to obtain the grayscale resource allocation result. The mapping generation module is used to determine the regional output driving code and establish a grayscale driving correction mapping table based on the object-level unified target brightness, grayscale resource allocation results and the current effective driving code range. The local correction module is used to write the grayscale driving correction mapping table into the display control unit, and perform local verification and correction based on the actual display brightness to obtain an updated grayscale driving correction mapping table.

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