Real-time Management Method and System for Dynamic Backlight Distribution of LCD Stereolithography 3D Printer

Abstract

The present invention discloses a real-time processing method for dynamic backlight distribution of an LCD light-curing 3D printer. The sliced image data of the model to be printed is obtained. For each sliced image of each layer, the change situation in the sliced image sequence where it is located is calculated, that is, the overlapping area with the sliced images of the upper layer and the lower layer. When the ratio of the overlapping area with the upper layer to the area of the current layer is greater than a first preset value, the calculation of the two-dimensional irradiation distribution of the sliced image of this layer is skipped to affect the dimming of each LED; when the ratio of the overlapping area with the lower layer to the area of the current layer is less than a second preset value and greater than a third preset value, the change amount of the sliced image of the lower layer is calculated within the processing cycle of the current sliced image, and the actual power of the corresponding LED dimming block in the area where the increased or decreased area is located is calculated according to the change amount; for each sliced image, the irradiance of the LCD light-incident surface when the power of the corresponding LED dimming block changes incrementally or completely is calculated in real time.

Description

Technical Field

[0001] The present invention relates to the technical field of LCD photocuring 3D printing, and particularly to a method and system for real-time management of dynamic backlight distribution of an LCD photocuring 3D printer. Background Art

[0002] 3D printing (AM) is an emerging manufacturing technology different from traditional manufacturing, which combines scientific knowledge in multiple fields, such as computers, material processing, and machining. Among them, the photocuring 3D printing technology is an additive manufacturing process that selectively cures photocurable materials through photoactivated polymerization reactions. In this technology, the model is built layer by layer, either by scanning polymerization points (stereolithography - SLA) or by projecting the entire layer at once (digital light processing - DLP). The photocuring technology can be used to prepare models with high definition and smooth surfaces, and can have high precision without mechanical post-processing of the surface, thus showing great potential in the field of additive manufacturing.

[0003] Among them, LCD light-curing 3D printing technology is a brand-new 3D printing technology. It adopts surface exposure technology and has the advantages of low cost, high printing accuracy, and high efficiency. Its composition structure from top to bottom is generally an ultraviolet light source, an optical element for secondary light distribution, an LCD liquid crystal screen, a material tank, and a workbench that can move up and down and the Z-axis. Among them, the ultraviolet light source is one of the key factors affecting printing quality. The LCD light-curing printer realizes the printing of different layer patterns of photosensitive resin by controlling the different exposure energies of each pixel of the LCD liquid crystal screen. The exposure energy depends not only on the gray value of the pixel but also on the ultraviolet irradiance of the light incident surface of the physical pixel. The pixel gray value is determined by the sliced data of the model to be printed, and the ultraviolet irradiance is determined by the ultraviolet light source. Existing ultraviolet light sources can generally be divided into integrated light sources and array light sources. The former has a relatively simple structure and control, but there are problems such as high power consumption and light leakage. Moreover, when the ultraviolet light source directly irradiates the LCD liquid crystal screen for a long time, the service life of the LCD liquid crystal screen is shortened. The latter can achieve higher uniformity. At the same time, with the introduction of independent zone control, it can play the role of reducing power consumption and extending the service life of the LCD liquid crystal screen. However, each light source in the array light source with independent zone control only has two states: fully on or fully off, and the adjustment range is limited. Moreover, when the light source changes from bright to dark, it is difficult to predict and calculate the change situation of the ultraviolet irradiance of the ultraviolet light source. This results in the existing array light source technology being unable to effectively solve the problems of multi-gray printing and high-uniformity printing. The prior art CN114536749A proposes a method for real-time calculation of dynamic backlight distribution and a light source module for an LCD light-curing 3D printer. The method adopted is to construct a two-dimensional irradiance distribution grid on the light incident surface of the LCD, construct a database in which the power of the LED dimming block corresponds one-to-one with the sub-irradiance distribution grid, obtain the sliced image data of the model to be printed, partition the sliced image so that each partition of the sliced image corresponds to an LED dimming block in the LED backlight array, calculate the initial power of the LED dimming block according to the gray information of the pixels in the partition, obtain the actual power of each LED dimming block, splice together each sub-irradiance grid, and calculate the overall irradiance distribution of the LED backlight array. The present invention finally obtains the overall irradiance distribution of the LED backlight by calculating the irradiance of the light incident surface of the LCD in real time when the power of the LED dimming block in the LED backlight array changes. However, the above method has a high demand for the computing power of the printing device. It requires that each partition of the sliced image in the printed model corresponds to an LED dimming block in the LED backlight array, and it also requires splicing multiple sub-irradiance grids and then uniformly calculating the distribution situation, which causes a great computational burden on the entire 3D printing system. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention discloses a real-time processing method for dynamic backlight distribution of an LCD light-curing 3D printer. The processing method includes the following steps:

[0005] Step 1, obtain the sliced image data of the model to be printed. For each sliced image of each layer, calculate the change situation in the sliced image sequence where it is located, that is, the overlapping area with the sliced images of the upper layer and the lower layer. When the ratio of the overlapping area with the upper layer to the area of the current layer is greater than a first preset value, skip the calculation of the two-dimensional irradiation distribution of this layer of sliced image to the influence of each LED dimming.

[0006] Step 2, when the ratio of the overlapping area with the lower layer to the area of the current layer is less than a second preset value and greater than a third preset value, calculate the change amount of the sliced image of the lower layer within the processing period of the current sliced image, and calculate the actual power of the corresponding LED dimming block for the area where the increased or decreased area is located according to the change amount.

[0007] Step 3, when the ratio is less than the third preset value, re-partition the sliced image of the lower layer, and re-map the partition of the sliced image to the LED dimming blocks in the LED backlight array.

[0008] Step 4, calculate the irradiance on the LCD light-incident surface in real time for each layer of sliced image when the power of the corresponding LED dimming block changes incrementally or completely, so as to simplify the operation.

[0009] Furthermore, before step 1, first measure the irradiance values of the LED dimming blocks on the light-incident surface of the LCD at different powers, and establish the mapping between the irradiance distribution of the LED dimming blocks at different powers and the power of the LED dimming blocks.

[0010] Furthermore, the change amount of the sliced image of the lower layer is the absolute value of the area occupied by the sliced image of the lower layer minus the area occupied by the sliced image of the current layer.

[0011] Furthermore, the first preset value is greater than the second preset value. The third preset value is less than the second preset value.

[0012] The present invention also discloses a real-time processing system for dynamic backlight distribution of an LCD light-curing 3D printer. The processing system includes a sliced data acquisition unit. Through the sliced data acquisition unit, obtain the sliced image data of the model to be printed. For each sliced image of each layer, calculate the change situation in the sliced image sequence where it is located, that is, the overlapping area with the sliced images of the upper layer and the lower layer. When the ratio of the overlapping area with the upper layer to the area of the current layer is greater than a first preset value, skip the calculation of the two-dimensional irradiation distribution of this layer of sliced image to the influence of each LED dimming.

[0013] A slice data comparison unit, when the ratio of the overlapping area with the next layer to the area of the current layer is less than a second preset value and greater than a third preset value, calculates the change amount of the slice image of the next layer within the processing cycle of the current slice image, and calculates the actual power of the corresponding LED dimming block for the partition where the increased or decreased area is located according to the change amount;

[0014] A remapping unit, when the ratio is less than the third preset value, remaps the slice image of the next layer through the remapping unit, and remaps the partition of the slice image to the LED dimming blocks in the LED backlight array;

[0015] An irradiance calculation unit calculates the irradiance on the LCD light-incident surface in real time for each layer of slice image when the power of the corresponding LED dimming block changes incrementally or completely, so as to simplify the operation.

[0016] Furthermore, before the slice data acquisition unit executes, first measure the irradiance values of the LED dimming blocks on the light-incident surface of the LCD at different powers, and establish the mapping between the irradiance distribution of the LED dimming blocks at different powers and the power of the LED dimming blocks.

[0017] Furthermore, the change amount of the slice image of the next layer is the absolute value of the area occupied by the slice image of the next layer minus the area occupied by the slice image of the current layer.

[0018] Furthermore, the first preset value is greater than the second preset value.

[0019] Furthermore, the third preset value is less than the second preset value.

[0020] In view of the prior art, the beneficial effects of the present invention are very remarkable. The prior art has a relatively high demand for the computing power of printing devices. For each slice image in the printing model, the partition corresponds to one LED dimming block in the LED backlight array, and it is also necessary to splice multiple sub-irradiance grids and then uniformly calculate the distribution situation, which causes a great computing burden on the entire 3D printing system. The beneficial effects of the present invention are as follows: The present invention discloses a real-time processing method for dynamic backlight distribution of an LCD light-curing 3D printer, which obtains the slice image data of the model to be printed. For each layer of slice image, calculate the change situation in the slice image sequence where it is located, that is, the overlapping area with the slice images of the upper layer and the lower layer. When the ratio of the overlapping area with the upper layer to the area of the current layer is greater than the first preset value, skip the calculation of the two-dimensional irradiation distribution of the slice image of this layer and its influence on the dimming of each LED; when the ratio of the overlapping area with the lower layer to the area of the current layer is less than the second preset value and greater than the third preset value, calculate the change amount of the slice image of the lower layer within the processing cycle of the current slice image, and calculate the actual power of the corresponding LED dimming block for the partition where the increased or decreased area is located according to the change amount; when the ratio is less than the third preset value, re-partition the slice image of the lower layer and remap the partition of the slice image to the LED dimming block in the LED backlight array; for each layer of slice image, calculate the irradiance on the LCD light-incident surface in real time when the power of the corresponding LED dimming block changes incrementally or completely, so as to simplify the operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present invention can be further understood from the following description with reference to the accompanying drawings. The components in the drawings are not necessarily drawn to scale, but the emphasis is placed on showing the principles of the embodiments. In the drawings, the same reference numerals designate corresponding parts in different views.

[0022] Figure 1 It is a flowchart of the real-time processing method for dynamic backlight distribution of the LCD light-curing 3D printer of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] Embodiment 1

[0024] As Figure 1 shown, this embodiment provides a real-time processing method for dynamic backlight distribution of an LCD light-curing 3D printer, and the processing method includes the following steps:

[0025] Step 1: Obtain the sliced image data of the model to be printed. For each layer of sliced image, calculate the change situation in the sequence of sliced images it belongs to, that is, the overlapping area with the sliced images of the upper layer and the lower layer. When the ratio of the overlapping area with the upper layer to the area of the current layer is greater than the first preset value, skip calculating the influence of the two-dimensional irradiation distribution of this layer of sliced image on the dimming of each LED.

[0026] Step 2: When the ratio of the overlapping area with the lower layer to the area of the current layer is less than the second preset value and greater than the third preset value, calculate the change amount of the sliced image of the lower layer within the processing period of the current sliced image, and calculate the actual power of the corresponding LED dimming block for the area where the area increases or decreases according to the change amount.

[0027] Step 3: When the ratio is less than the third preset value, repartition the sliced image of the lower layer again, and remap the partition of the sliced image to the LED dimming blocks in the LED backlight array.

[0028] Step 4: For each layer of sliced image, calculate the irradiance on the light incident surface of the LCD in real time when the power of the corresponding LED dimming block changes incrementally or completely, so as to simplify the operation.

[0029] Furthermore, before Step 1, first measure the irradiance values of the LED dimming blocks on the light incident surface of the LCD at different powers, and establish the mapping between the irradiance distribution of the LED dimming blocks at different powers and the power of the LED dimming blocks.

[0030] Furthermore, the change amount of the sliced image of the lower layer is the absolute value of the area occupied by the sliced image of the lower layer minus the area occupied by the sliced image of the current layer.

[0031] Furthermore, the first preset value is greater than the second preset value. The third preset value is less than the second preset value.

[0032] Embodiment 2

[0033] In this embodiment, from the hardware perspective, the inventive concept of the present invention is described, and a real-time processing system for dynamic backlight distribution of an LCD light-curing 3D printer is disclosed. The processing system includes a sliced data acquisition unit. Through the sliced data acquisition unit, obtain the sliced image data of the model to be printed. For each layer of sliced image, calculate the change situation in the sequence of sliced images it belongs to, that is, the overlapping area with the sliced images of the upper layer and the lower layer. When the ratio of the overlapping area with the upper layer to the area of the current layer is greater than the first preset value, skip calculating the influence of the two-dimensional irradiation distribution of this layer of sliced image on the dimming of each LED.

[0034] The slice data comparison unit calculates the change amount of the slice image of the next layer within the processing cycle of the current slice image when the ratio of the overlapping area with the next layer to the area of the current layer is less than the second preset value and greater than the third preset value, and calculates the actual power of the corresponding LED dimming block for the partition where the increased or decreased area is located according to the change amount;

[0035] The remapping unit remaps the partition of the slice image of the next layer through the remapping unit and remaps the partition of the slice image to the LED dimming block in the LED backlight array when the ratio is less than the third preset value;

[0036] The irradiance calculation unit calculates the irradiance on the light incident surface of the LCD in real time for each layer of slice image when the power of the corresponding LED dimming block changes incrementally or completely to simplify the operation.

[0037] Furthermore, before the slice data acquisition unit executes, first measure the irradiance values of the LED dimming blocks on the light incident surface of the LCD at different powers, and establish the mapping between the irradiance distribution of the LED dimming blocks at different powers and the power of the LED dimming blocks.

[0038] Furthermore, the change amount of the slice image of the next layer is the absolute value of the area occupied by the slice image of the next layer minus the area occupied by the slice image of the current layer.

[0039] Furthermore, the first preset value is greater than the second preset value.

[0040] Furthermore, the third preset value is less than the second preset value.

[0041] It should also be noted that the term "including", "comprising" or any other variation thereof is intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, commodity or device. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of additional identical elements in the process, method, commodity or device including the element.

[0042] Those skilled in the art should understand that the embodiments of the present application can be provided as methods, systems or computer program products. Therefore, the present application can take the form of a complete hardware embodiment, a complete software embodiment or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0043] Although the present invention has been described above with reference to various embodiments, it should be understood that many changes and modifications can be made without departing from the scope of the present invention. Therefore, it is intended that the above detailed description be considered illustrative rather than restrictive, and it should be understood that the following claims (including all equivalents) are intended to define the spirit and scope of the present invention. These embodiments should be understood to be only for illustrating the present invention and not for limiting the protection scope of the present invention. After reading the content recorded in the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent changes and modifications also fall within the scope defined by the claims of the present invention.

Claims

1. A real-time processing method for dynamic backlight distribution of an LCD light-curing 3D printer, characterized in that, The processing method includes the following steps: Step 1: Obtain the sliced image data of the model to be printed. For each layer of sliced image, calculate the change in the sequence of sliced images it belongs to, that is, the overlapping area with the sliced images of the upper layer and the lower layer. When the ratio of the overlapping area with the upper layer to the area of the current layer is greater than the first preset value, skip calculating the influence of the two-dimensional irradiation distribution of this layer of sliced image on the dimming of each LED. Step 2: When the ratio of the overlapping area with the lower layer to the area of the current layer is less than the second preset value and greater than the third preset value, calculate the change amount of the sliced image of the lower layer within the processing period of the current sliced image, and calculate the actual power of the corresponding LED dimming block for the partition where the increased or decreased area is located according to the change amount. Step 3: When the ratio is less than the third preset value, re-partition the sliced image of the lower layer, and remap the partition of the sliced image to the LED dimming blocks in the LED backlight array. Step 4: For each layer of sliced image, calculate the irradiance on the light incident surface of the LCD in real time when the power of the corresponding LED dimming block changes incrementally or completely, so as to simplify the operation. The first preset value is greater than the second preset value, and the third preset value is less than the second preset value.

2. The real-time processing method for dynamic backlight distribution of an LCD light-curing 3D printer according to claim 1, wherein, Before Step 1, first measure the irradiance values of the LED dimming blocks on the light incident surface of the LCD at different powers, and establish the mapping between the irradiance distribution of the LED dimming blocks at different powers and the power of the LED dimming blocks.

3. The real-time processing method for dynamic backlight distribution of an LCD light-curing 3D printer as claimed in claim 1, wherein The change amount of the sliced image of the lower layer is the absolute value of the area of the sliced image of the lower layer minus the area of the sliced image of the current layer.

4. A real-time processing system for dynamic backlight distribution of an LCD light-curing 3D printer, characterized in that, The processing system includes a sliced data acquisition unit. Through the sliced data acquisition unit, obtain the sliced image data of the model to be printed. For each layer of sliced image, calculate the change in the sequence of sliced images it belongs to, that is, the overlapping area with the sliced images of the upper layer and the lower layer. When the ratio of the overlapping area with the upper layer to the area of the current layer is greater than the first preset value, skip calculating the influence of the two-dimensional irradiation distribution of this layer of sliced image on the dimming of each LED. A sliced data comparison unit. When the ratio of the overlapping area with the lower layer to the area of the current layer is less than the second preset value and greater than the third preset value, calculate the change amount of the sliced image of the lower layer within the processing period of the current sliced image, and calculate the actual power of the corresponding LED dimming block for the partition where the increased or decreased area is located according to the change amount. A remapping unit. When the ratio is less than the third preset value, re-partition the sliced image of the lower layer through the remapping unit, and remap the partition of the sliced image to the LED dimming blocks in the LED backlight array. An irradiance calculation unit. For each layer of sliced image, calculate the irradiance on the light incident surface of the LCD in real time when the power of the corresponding LED dimming block changes incrementally or completely, so as to simplify the operation. The first preset value is greater than the second preset value, and the third preset value is less than the second preset value.

5. The real-time processing system for dynamic backlight distribution of an LCD light-curing 3D printer according to claim 4, characterized in that Before the slice data acquisition unit is executed, first measure the irradiance values of the LED dimming blocks on the light-incident surface of the LCD at different powers, and establish a mapping between the irradiance distribution of the LED dimming blocks at different powers and the power of the LED dimming blocks.

6. The real-time processing system for dynamic backlight distribution of an LCD light-curing 3D printer according to claim 4, wherein The change amount of the slice image of the next layer is the absolute value obtained by subtracting the area occupied by the slice image of the current layer from the area occupied by the slice image of the next layer.

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