阅读说明：本技术 三维打印方法和设备 (Three-dimensional printing method and apparatus ) 是由 侯锋 于 2019-04-09 设计创作，主要内容包括：本发明涉及一种三维打印方法,包括以下步骤：获取用于承载三维模型的承载台的平整度参数；根据特定三维模型在所述承载台上的布置位置以及所述平整度参数,确定所述特定三维模型的高度补偿值；以及曝光所述特定三维模型从面向所述承载台的底面起的至少一层,其中根据所述高度补偿值确定所述特定三维模型的增加或减少的层数。根据本发明的三维打印方法,可以使位于承载台上具有不同平整度参数的位置上的特定三维模型都具有相同的高度/厚度,保证同一批打印出来的各个特定三维模型在Z轴(高度方向)上的一致性,提高三维模型的Z轴精度。(The invention relates to a three-dimensional printing method, which comprises the following steps: acquiring flatness parameters of a bearing table for bearing the three-dimensional model; determining a height compensation value of a specific three-dimensional model according to the arrangement position of the specific three-dimensional model on the bearing table and the flatness parameter; and exposing at least one layer of the specific three-dimensional model from the bottom surface facing the bearing table, wherein the number of the increased or decreased layers of the specific three-dimensional model is determined according to the height compensation value. According to the three-dimensional printing method, the specific three-dimensional models positioned on the positions with different flatness parameters on the bearing table have the same height/thickness, the consistency of each specific three-dimensional model printed in the same batch on the Z axis (height direction) is ensured, and the Z axis precision of the three-dimensional models is improved.)

1. A three-dimensional printing method comprising the steps of:

acquiring flatness parameters of a bearing table for bearing the three-dimensional model;

determining a height compensation value of a specific three-dimensional model according to the arrangement position of the specific three-dimensional model on the bearing table and the flatness parameter; and

exposing at least one layer of the specific three-dimensional model from the bottom surface facing the bearing table, wherein the number of the increased or decreased layers of the specific three-dimensional model is determined according to the height compensation value.

2. The three-dimensional printing method of claim 1, wherein the step of obtaining flatness parameters of a stage for carrying the three-dimensional model comprises:

printing at least one three-dimensional model at each position of the bearing table according to a standard data model;

calculating an error of the at least one three-dimensional model relative to the normative data model; and

and determining flatness parameters of each position of the bearing table according to each error.

3. The three-dimensional printing method of claim 2, wherein when the height of the selected region of the at least one three-dimensional model is higher than the height of the corresponding region of the standard data model, the corresponding flatness parameter is a positive value; when the height of the at least one three-dimensional model is lower than the height of the standard data model, the corresponding flatness parameter is a negative value.

4. The three-dimensional printing method according to claim 1 or 2, wherein the step of determining the height compensation value of the specific three-dimensional model according to the arrangement position of the specific three-dimensional model on the bearing table and the flatness parameter comprises:

obtaining a flatness parameter of the arrangement position;

and determining the height compensation value according to the flatness parameter of the arrangement position, wherein the height compensation value has a sign opposite to that of the flatness parameter.

5. The three-dimensional printing method according to claim 4, wherein the step of determining the increased or decreased number of layers of the specific three-dimensional model according to the height compensation value includes:

when the height compensation value of the specific three-dimensional model is a positive value, postponing one or more layers of printing of the bottom slice image of the data model of the specific three-dimensional model;

when the height compensation value of the specific three-dimensional model is a negative value, removing one or more layers of slice images from the bottommost layer of the data model of the specific three-dimensional model;

and when the height compensation value of the specific three-dimensional model is zero, keeping the number of slice image layers of the data model of the specific three-dimensional model.

6. The three-dimensional printing method according to claim 1, wherein each layer of the specific three-dimensional model has a thickness of 0.05 to 0.3 mm.

7. The three-dimensional printing method according to claim 5, wherein the number of layers is 2-5 layers.

8. The three-dimensional printing method of claim 1, wherein the method prints using a photo-curing process.

9. The three-dimensional printing method of claim 1, wherein the three-dimensional model is a dental model.

10. A three-dimensional printing apparatus adapted to print a three-dimensional model, the three-dimensional printing apparatus comprising a printing mechanism and a controller configured to control the printing mechanism to perform the method of any of claims 1-9.

11. A computer-readable medium having stored thereon computer program code which, when executed by a processor, implements the method of any of claims 1-9.

Technical Field

The invention relates to a three-dimensional printing technology, in particular to a three-dimensional printing method and equipment when a bearing platform for bearing a three-dimensional model is uneven.

Background

The three-dimensional printing technology is characterized in that a computer three-dimensional design model is used as a blueprint, special materials such as metal powder, ceramic powder, plastics, cell tissues and the like are stacked layer by layer and bonded through a software layering dispersion and numerical control forming system in a laser beam mode, a hot melting nozzle mode and the like, and finally, an entity product is manufactured through superposition forming. The forming mode of the three-dimensional printing technology is continuously evolving, and among various forming modes, the photocuring method is a mature mode. The light curing method is to use the principle that light curing materials are cured after being irradiated by ultraviolet light to perform material accumulation molding, and has the characteristics of high molding precision, good surface smoothness, high material utilization rate and the like.

Fig. 1 is a schematic diagram of a basic structure of a photocuring-type three-dimensional printing apparatus. Referring to fig. 1, a three-dimensional printing apparatus 100 of a photo-curing type includes a material tank 110 for containing printing resin, a carrying platform 120 for carrying a molded workpiece, a coating blade 130 for spreading the printing resin, an image exposure system 140 for curing the printing resin, and a control system (not shown) for controlling the actions of the carrying platform 120, the coating blade 130, and the image exposure system 140. The image exposure system 140 is disposed above the material tank 110 and irradiates a beam image to cure a layer of printing resin on the bottom surface 121 of the stage 120. After the curing of one layer of printing resin is completed, the control system controls the bearing platform 120 to drive the formed layer of cured printing resin to slightly descend, and the coating scraper 130 moves to uniformly spread a layer of liquid printing resin on the top surface of the cured workpiece to wait for the next irradiation. And circulating the steps, and obtaining the three-dimensional workpiece formed by layer-by-layer accumulation.

When printing less model like the tooth model, can print the same layer of a plurality of models simultaneously, this a plurality of models can alternate and distribute on plummer 120 to improve printing efficiency. Ideally, the bottom surface 121 of the susceptor 120 should be a flat horizontal surface. However, in practical applications, the bottom surface 121 of the carrier table 120 may become uneven for some reason, such as unevenness of some parts on the bottom surface 121 due to wear in use, or inclination of the carrier table 120 due to unevenness of the floor of the three-dimensional printing apparatus, and so on. Thus, in the case where the model is printed directly from the bottom surface of the carrier 120 without using a support, the Z-axis accuracy of the three-dimensional model is reduced because the height/thickness of the model printed in the same batch is not uniform due to the unevenness of the bottom surface 121 of the carrier 120, and the Z-axis accuracy of the three-dimensional model is measured by the height/thickness of the model.

Disclosure of Invention

The invention aims to provide a three-dimensional printing method and equipment, which can solve the problem of inconsistent printing model height caused by uneven bearing platform.

The invention adopts the technical scheme to solve the technical problems and provides a three-dimensional printing method, which comprises the following steps: acquiring flatness parameters of a bearing table for bearing the three-dimensional model; determining a height compensation value of a specific three-dimensional model according to the arrangement position of the specific three-dimensional model on the bearing table and the flatness parameter; and exposing at least one layer of the specific three-dimensional model from the bottom surface facing the bearing table, wherein the number of the increased or decreased layers of the specific three-dimensional model is determined according to the height compensation value.

Optionally, the step of obtaining flatness parameters of a stage for carrying the three-dimensional model includes: printing at least one three-dimensional model at each position of the bearing table according to a standard data model; calculating an error of the at least one three-dimensional model relative to the normative data model; and determining flatness parameters of each position of the bearing table according to each error.

Optionally, when the height of the selected region of the at least one three-dimensional model is higher than the height of the corresponding region of the standard data model, the corresponding flatness parameter is a positive value; when the height of the at least one three-dimensional model is lower than the height of the standard data model, the corresponding flatness parameter is a negative value.

Optionally, the step of determining a height compensation value of a specific three-dimensional model according to the arrangement position of the specific three-dimensional model on the bearing table and the flatness parameter comprises: obtaining a flatness parameter of the arrangement position; and determining the height compensation value according to the flatness parameter of the arrangement position, wherein the height compensation value has a sign opposite to that of the flatness parameter.

Optionally, the step of determining the number of layers to be added or subtracted for the specific three-dimensional model according to the height compensation value comprises: when the height compensation value of the specific three-dimensional model is a positive value, postponing one or more layers of printing of the bottom slice image of the data model of the specific three-dimensional model; when the height compensation value of the specific three-dimensional model is a negative value, removing one or more layers of slice images from the bottommost layer of the data model of the specific three-dimensional model; and when the height compensation value of the specific three-dimensional model is zero, keeping the number of slice image layers of the data model of the specific three-dimensional model.

Optionally, each layer of the specific three-dimensional model has a thickness of 0.05-0.3 mm.

Optionally, the number of layers is 2-5 layers.

Alternatively, the method prints using a photo-curing method.

Optionally, the three-dimensional model is a tooth model.

The present invention further provides a three-dimensional printing apparatus adapted to print a three-dimensional model, the three-dimensional printing apparatus including a printing mechanism and a controller configured to control the printing mechanism to perform the method as described above.

The solution adopted by the present invention to solve the above technical problem also includes a computer readable medium storing computer program code, which when executed by a processor implements the method as described above.

The invention has the advantages that the three-dimensional printing method and the three-dimensional printing equipment are provided, the height compensation value of the specific three-dimensional model is determined according to the flatness parameters of the bearing platform bearing the three-dimensional model and the arrangement position of the specific three-dimensional model on the bearing platform, and the printing process is controlled according to the height compensation value, so that the specific three-dimensional models at the positions with different flatness parameters on the bearing platform have the same height/thickness, the consistency of each specific three-dimensional model printed in the same batch on the Z axis (height direction) is ensured, and the Z axis precision of the three-dimensional model is improved.

Drawings

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below, wherein:

fig. 1 is a schematic diagram of a basic structure of a photo-curing type three-dimensional printing apparatus;

FIG. 2 is an exemplary flow diagram of a three-dimensional printing method according to an embodiment of the invention;

3A-3D are schematic diagrams of exemplary processes for three-dimensional printing according to a three-dimensional printing method of an embodiment of the invention;

4A-4D are schematic diagrams of another exemplary process for three-dimensional printing according to a three-dimensional printing method of an embodiment of the present invention;

fig. 5A-5C are schematic diagrams of another exemplary process of three-dimensional printing according to a three-dimensional printing method according to an embodiment of the present invention.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other ways than those specifically described herein, and thus the present invention is not limited to the specific embodiments disclosed below.

As used in this application and the appended claims, the terms "a," "an," and/or "the" are not intended to be inclusive in the singular, but rather are intended to be inclusive in the plural unless the context clearly dictates otherwise. In general, the terms "comprises" and "comprising" merely indicate that steps and elements are included which are explicitly identified, that the steps and elements do not form an exclusive list, and that a method or apparatus may include other steps or elements.

For convenience in description, spatial relational terms such as "below," "beneath," "below," "under," "over," "upper," and the like may be used herein to describe one element or feature's relationship to another element or feature as illustrated in the figures. It will be understood that these terms of spatial relationship are intended to encompass other orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the exemplary words "below" and "beneath" can encompass both an orientation of up and down. The device may have other orientations (rotated 90 degrees or at other orientations) and the spatial relationship descriptors used herein should be interpreted accordingly. Further, it will also be understood that when a layer is referred to as being "between" two layers, it can be the only layer between the two layers, or one or more intervening layers may also be present.

Fig. 2 is an exemplary flowchart of a three-dimensional printing method according to an embodiment of the present invention. Referring to fig. 2, the three-dimensional printing method of the present invention includes the steps of:

step 210, obtaining flatness parameters of the bearing table 120 for bearing the three-dimensional model.

In the case where the bottom surface 121 of the susceptor 120 is flat, the height of the susceptor 120 is set to be a normal height. When the bottom surface 121 of the susceptor 120 is uneven, there are two cases.

First, the height of the bottom surface 121 of the carrier 120 is higher than the normal height. Assuming that the printing resin is contained in the material tank 110 and horizontally spread on the bottom surface 121 of the susceptor 120 when the three-dimensional model printing is performed, the thickness on the bottom surface 121 of the susceptor 120 corresponding to the normal height is assumed to be d. Then the printing resin thickness will be less than d for locations where the height of the bottom surface 121 is higher than normal. When three-dimensional printing is carried out, the thickness of the printing resin at the position after curing is smaller than d, and for the whole three-dimensional model, one layer or a plurality of layers of models are printed, so that the height/thickness of the three-dimensional model is smaller than the normal height/thickness.

Second, the height of the bottom surface 121 of the carrier 120 is lower than the normal height. Assuming that printing resin is contained in the material tank 110 and horizontally spread on the bottom surface 121 of the carrying table 120 when the three-dimensional model printing is performed, and the thickness on the bottom surface 121 of the carrying table 120 corresponding to the normal height is assumed to be d, the thickness of the printing resin covered on the bottom surface 121 is larger than d for the position where the height of the bottom surface 121 is lower than the normal height. When three-dimensional printing is carried out, the thicker resin can still be solidified due to the certain penetrating capacity of the solidified light, the layer of three-dimensional model positioned at the position lower than the normal height has the height/thickness larger than d, and the height/thickness of the whole three-dimensional model is larger than the normal height/thickness.

The error that a position on the carrier table 120 is higher or lower than the normal height is used as a flatness parameter for representing the flatness of the position. This step is to obtain the flatness parameters of each or several representative positions on the carrier 120.

A specific method for acquiring the flatness parameter in this step will be described in detail later.

In step 220, a height compensation value for the particular three-dimensional model is determined.

In this step, the height compensation value of the specific three-dimensional model is determined according to the arrangement position of the specific three-dimensional model on the carrier table 120 and the flatness parameter obtained in step 210. The specific three-dimensional model is a three-dimensional model to be three-dimensionally printed.

In some embodiments, these particular three-dimensional models are tooth models.

When a plurality of specific three-dimensional models are printed simultaneously, each specific three-dimensional model is arranged at a position on the carrier table 120, which is referred to as an arrangement position of the specific three-dimensional model on the carrier table 120. In step 210, flatness parameters of the carrier table 120 have been obtained. Then at step 220, flatness parameters corresponding to the placement locations of each particular three-dimensional model may be known.

When the flatness parameter of the arrangement position of a specific three-dimensional model indicates that the height of the arrangement position is higher than the normal height, that is, the height/thickness of the specific three-dimensional model at the arrangement position may be smaller than the normal height/thickness, the height compensation value of the specific three-dimensional model is used to supplement the height/thickness of the specific three-dimensional model.

When the flatness parameter of the arrangement position of a specific three-dimensional model indicates that the height of the arrangement position is lower than the normal height, that is, the height/thickness of the specific three-dimensional model at the arrangement position may be larger than the normal height/thickness, the height compensation value of the specific three-dimensional model is used for reducing the height/thickness of the specific three-dimensional model.

The specific method for this step will be described in detail later.

The number of layers to be added or subtracted for a particular three-dimensional model is determined based on the height compensation value, step 230.

If the height compensation value corresponding to the specific three-dimensional model indicates that the height/thickness of the specific three-dimensional model may be smaller than the normal height/thickness, in the printing process, the slice image at the bottommost layer of the data model of the specific three-dimensional model is postponed for one or more layers of printing, or the image at the bottommost layer can be copied for one or more layers of exposure, so as to increase the number of printing layers.

If the height compensation value corresponding to the specific three-dimensional model indicates that the height/thickness of the specific three-dimensional model may be larger than the normal height/thickness, in the printing process, one or more layers of slice images are removed from the lowest layer of the data model of the specific three-dimensional model to achieve a smaller number of printing layers, and since the printing layer thickness is generally fixed, the purposes of reducing the total printing height and balancing the error of the bottom surface 121 of the bearing table 120 are achieved.

Of course, if a larger model is printed, the compensation data of the areas of the bottom surface 121 of the plurality of loading platforms 120 covered by the model can be averaged to determine the compensation value, and thus the number of layers to be added or subtracted for the three-dimensional model can be determined

The specific method for this step will be described in detail later.

At step 240, at least one layer of the three-dimensional model from the bottom surface facing the stage 120 is exposed.

In this step, the data model for the particular three-dimensional model has been processed as in step 230 according to the height compensation value corresponding to the particular three-dimensional model.

The above steps will be specifically described below.

In step 210, the step of obtaining the flatness parameters of the stage 120 for carrying the three-dimensional model includes:

(1) at least one three-dimensional model is printed at each location on the carrier 120 according to a standard data model.

In some embodiments, the standard data model may be a model with a complete bottom surface, and the bottom surface of the model may completely cover the bottom surface 121 of the carrier 120, so that the flatness of the bottom surface 121 of the carrier 120 can be determined according to the height of the three-dimensional model printed by the standard data model.

In other embodiments, the standard data model may have floor data only at several representative locations. Such as at the center of the bottom surface 121 of the platform 120, at the angle of each side, at the middle of each side, etc. According to the standard data model, a three-dimensional model with a plurality of bottom surfaces, for example, a table-shaped model with a plurality of pillars, can be printed, and a plurality of mutually independent three-dimensional models, for example, a plurality of square-shaped models can be printed at the representative positions. The height of these models may reflect the flatness of the bottom surface 121 of the carrier 120 in which they are located.

The heights of the standard data models should be consistent, but there may be printing system systematic errors, such as all printed standard models being higher than the standard height by a systematic error value, for which the printing system actually has special tuning means (not discussed in detail herein), where the "standard height" is actually the average, minimum or maximum of all the printing model heights, and in any event, there should be at least one model having a flatness parameter of 0 or approaching 0, and no case should occur where the height systematic errors are calibrated in this method.

(2) An error of the at least one three-dimensional model relative to the standard data model is calculated.

Due to the unevenness of the bottom surface 121 of the susceptor 120, there may be an error between the height/thickness of the three-dimensional model printed according to the standard data model and the height/thickness set in the standard data model.

In some embodiments, when a three-dimensional model is printed according to the standard data model, the three-dimensional model covers the entire bottom surface 121 of the carrier 120, and the height of each position of the three-dimensional model reflects the flatness of the carrier 120 corresponding to the position of the three-dimensional model. If there is an error between the height and the standard data model, it indicates that the bottom surface 121 of the carrier 120 at the position is uneven. Specifically, the bottom surface 121 of the susceptor 120 may be divided into regions according to the size of the three-dimensional model to be printed. The areas may be evenly or unevenly distributed, and the size of each area may be the same or different, according to the actual needs of the user. And calculating the average height of the three-dimensional model in a certain area, comparing the average height with the standard height of the area corresponding to the standard data model, and if an error exists, indicating that the bottom surface 121 of the bearing table 120 in the area is uneven.

In other embodiments, when a plurality of three-dimensional models are printed according to the standard data model, the actual height of each three-dimensional model is compared with the standard height of the standard data model of the corresponding region, since the height of each three-dimensional model reflects the flatness of the bottom surface 121 of the carrier 120 at the position of the three-dimensional model. If there is an error, it indicates that the bottom surface 121 of the susceptor 120 at the position is uneven.

(3) Flatness parameters of each position of the carrier table 120 are determined according to each error.

Here, the aforementioned error of the three-dimensional model of each position may be taken as its flatness parameter. When the height of one three-dimensional model is higher than the standard height of the corresponding area of the standard data model, the flatness parameter corresponding to the position of the three-dimensional model is a positive value. At this time, the height of the bottom surface 121 of the carrier 120 at the position corresponding to the three-dimensional model is lower than the normal height. When the height of a three-dimensional model is lower than the standard height of the corresponding area of the standard data model, the flatness parameter corresponding to the position of the three-dimensional model is a negative value. At this time, the height of the bottom surface 121 of the carrier 120 at the position corresponding to the three-dimensional model is higher than the normal height. And when the height of one three-dimensional model is equal to the standard height of the corresponding area of the standard data model, the flatness parameter corresponding to the position of the three-dimensional model is zero. Here, the flatness parameter is a result of comparison with the normal height, and has a positive value, a negative value, or zero. It is to be understood that the sign of positive and negative values is not exclusive and can be inverted. In addition, the use of flatness parameters having positive and negative values herein may facilitate subsequent height compensation. In other embodiments, the flatness parameter may also be a positive value that indicates the height difference between each position of the carrier and the lowest position, or a negative value that indicates the height difference between each position of the carrier and the highest position. It should be noted that, in each position of the susceptor 120, at least one position has a flatness parameter of zero or close to 0.

In step 220, a height compensation value of the specific three-dimensional model is determined according to the arrangement position of the specific three-dimensional model on the bearing table 120 and the flatness parameter. The method comprises the following steps:

(1) flatness parameters of the arrangement positions are obtained.

The placement position of a particular three-dimensional model on the carrier table 120 is known prior to three-dimensional printing of the particular three-dimensional model. The user may place a number of specific three-dimensional models on the carrier 120 as desired. Flatness parameters for respective positions on the stage 120 have been obtained in step 210, and therefore, when a specific three-dimensional model is printed, a flatness parameter relating to the arrangement position of the specific three-dimensional model can be obtained from the flatness parameters.

(2) And determining a height compensation value according to the flatness parameter of the arrangement position, wherein the height compensation value has a sign opposite to that of the flatness parameter.

Namely, when the flatness parameter of a certain arrangement position of the specific three-dimensional model is a positive value, the height compensation value corresponding to the arrangement position is a negative value; when the flatness parameter of a certain arrangement position of the specific three-dimensional model is a negative value, the height compensation value corresponding to the arrangement position is a positive value.

In some embodiments, the height compensation value and the flatness parameter may be equal in value and opposite in sign.

In step 230, the step of determining the number of layers to be added or subtracted for a specific three-dimensional model according to the height compensation value is different according to the height compensation value, and specifically includes the following three cases:

(1) and when the height compensation value of the specific three-dimensional model is a positive value, postponing one or more layers of printing of the bottommost slice image of the data model of the specific three-dimensional model. It is understood that, in this case, the height of the bottom surface 121 of the carrier table 120 at the arrangement position corresponding to the specific three-dimensional model is higher than the normal height. Thus, when three-dimensionally printing one or several layers of the lowermost slice image of a specific three-dimensional model, the printing resin height at the arrangement position is lower than the normal height, and therefore the actual printing model height will also be lower than the normal height. It will be appreciated that the delay in printing the one or more layers may also be the copying of the exposure of the lowermost image to the one or more layers at the location of the arrangement to ensure the adhesion of the former and the support platform.

(2) When the height compensation value of the specific three-dimensional model is a negative value, removing one or more layers of slice images from the bottommost layer of the data model of the specific three-dimensional model; it will be understood that in this case, the height of the bottom surface 121 of the carrier table 120 at the arrangement position corresponding to the specific three-dimensional model is lower than the normal height. The thickness of the liquid printing resin at the arrangement position is thicker than the thickness of the liquid printing resin at the arrangement position at the normal height, and therefore, removing one or more layers of the slice images from the lowermost layer of the data model of the specific three-dimensional model can make the height/thickness of the specific three-dimensional model equal to the normal height/thickness.

(3) When the height compensation value of the specific three-dimensional model is zero, the number of slice image layers of the data model of the specific three-dimensional model is maintained.

In some embodiments, the number of layers is 2-5 layers, with the particular number depending on the quotient of the height compensation value of the particular three-dimensional model divided by the thickness of each layer.

In step 240, at least one layer of the particular three-dimensional model from the bottom surface facing the stage is exposed. After the data model of the three-dimensional model is determined in step 230, the specific three-dimensional model is exposed layer by layer according to the photo-curing three-dimensional printing method, and finally the complete three-dimensional model is printed.

The three-dimensional printing process when the height compensation value of a specific three-dimensional model is a positive value and a negative value is illustrated in conjunction with fig. 3A to 3D and fig. 4A to 4D.

3A-3D are situations when the height compensation value for a particular three-dimensional model is positive. In this example, it is assumed that the three-dimensional printing device prints three specific three-dimensional models, a first specific three-dimensional model 310, a second specific three-dimensional model 320, and a third specific three-dimensional model 330, respectively, at the same time. It is to be understood that fig. 3A-3D are exemplary diagrams only, and are not intended to limit the form or number of particular three-dimensional models of the present invention.

In some embodiments, each layer of these particular three-dimensional models has a thickness of 0.05-0.3mm during printing.

Referring to fig. 3A, a bottom surface 121 of a stage 120 of a three-dimensional printing apparatus is inclined, and a layer of printing resin is present on the bottom surface 121 of the stage 120, and a liquid surface 122 of the layer of printing resin is horizontal. The liquid level part on the left side of the bottom surface 121 of the bearing table 120 is lower than the normal liquid level 122, and the liquid level part on the right side of the bottom surface 121 of the bearing table 120 is the liquid level 122 of the normal printing resin.

Referring to fig. 3A-3D, the first, second and third specific three- dimensional models 310, 320 and 330 are disposed at right, middle and left sides of the bottom surface 121 of the carrier 120, respectively. If the height of the right side of the platform 120 is equal to the normal height of the platform 120, the height compensation value corresponding to the first specific three-dimensional model 310 is zero; if the height of the middle position of the carrier table 120 is higher than the normal height of the carrier table 120, the height compensation value corresponding to the second specific three-dimensional model 320 is a positive value; the height of the position on the left side of the carrier table 120 is higher than the normal height of the carrier table 120, and is also higher than the height of the middle part of the carrier table 120, so that the height compensation value corresponding to the third specific three-dimensional model 330 is also a positive value. In the embodiment shown in fig. 3A to 3D, it is assumed that the height of the arrangement position at which the second specific three-dimensional model 320 is located is one layer thickness higher than the normal height, and the height of the arrangement position at which the third specific three-dimensional model 330 is located is two layer thicknesses higher than the normal height.

It is understood that if the first, second and third specific three- dimensional models 310, 320 and 330 are printed simultaneously, the printing of the bottom layer of the three-dimensional model located at the right side of the carrier 120 is first performed and the printing of the second and third specific three- dimensional models 320 and 330 is postponed by postponing the printing, or the image exposure of the bottom layer can be duplicated when the first layer is printed.

Fig. 3B is a step of performing three-dimensional printing in the case shown in fig. 3A. According to step 230, since the height compensation value of the first specific three-dimensional model 310 is zero, the number of slice image layers of the first specific three-dimensional model 310 to be printed can be kept constant. Then at the step shown in fig. 3B, a first layer slice image of the first particular three-dimensional model 310 is printed using the image exposure system 140 in the three-dimensional printing device. The bottom slice images of the data models of the second specific three-dimensional model 320 and the third specific three-dimensional model 330 are not printed for the moment, that is, the bottom slice images of the data models of the second specific three-dimensional model 320 and the third specific three-dimensional model 330 are printed one layer later. Or the bottom images of the second specific three-dimensional model 320 and the third specific three-dimensional model 330 may be copied and a layer exposure may be performed at the corresponding position according to the copied images

Fig. 3C is a step after the printing step shown in fig. 3B. After the step shown in fig. 3B is completed, the carrier 120 of the three-dimensional printing apparatus drives the first layer of light-cured three-dimensional model to descend together, and the coating scraper 130 uniformly spreads a layer of liquid printing resin on the top surface of a layer of cured workpiece by moving, so as to be used for printing the next layer of three-dimensional model. Referring to fig. 3C, at this time, for the first specific three-dimensional model 310, the three-dimensional printing apparatus prints in accordance with its second layer cut image. For the second specific three-dimensional model 320 located in the middle of the bottom surface 121 of the carrier, the printing of the bottom slice image of the data model of the second specific three-dimensional model 320 is postponed by one layer according to the height compensation value, so that, at this step, the printing of the bottom slice image of the second specific three-dimensional model 320 can be started. As shown in FIG. 3C, the first layer slice images of the second particular three-dimensional model 320 have the same fill pattern as the first layer slice images of the first particular three-dimensional model 310, indicating that both are the first layer of the respective particular three-dimensional model. The bottom-most slice image of the data model of the third particular three-dimensional model 330 is delayed by one layer of printing, or the bottom-most image of the third particular three-dimensional model 330 may be copied and a layer of exposure may be performed at the corresponding location based on the copied image.

Fig. 3D is a step subsequent to the printing step shown in fig. 3C. Similar to the step shown in fig. 3C, after the step shown in fig. 3C is completed, the carrier 120 of the three-dimensional printing apparatus drives the first two layers of the photocured first specific three-dimensional model 310 and the first layer of the second specific three-dimensional model 320 to descend together, and the coating blade 130 uniformly spreads a layer of liquid printing resin on the top surface of the cured workpiece by moving, so as to be used for printing the next layer of three-dimensional model. Referring to FIG. 3D, at this point, for the first particular three-dimensional model 310, the three-dimensional printing device prints according to its third layer slice image; for the second particular three-dimensional model 320, the three-dimensional printing device prints according to its second layer slice image. For the third specific three-dimensional model 330 located on the left side of the bottom surface 121 of the carrier, the bottom slice image of the data model of the third specific three-dimensional model 330 is postponed from being printed by two layers according to the height compensation value, so that at this step, the printing of the bottom slice image of the third specific three-dimensional model 330 can be started. As shown in fig. 3D, the first layer slice image of the third specific three-dimensional model 330 has the same fill pattern as the first layer slice image of the first specific three-dimensional model 310 and the first layer slice image of the second specific three-dimensional model 320, which indicates that all three are the first layers of the respective specific three-dimensional models. Similarly, the second layer slice image of the second particular three-dimensional model 320 and the second layer slice image of the first particular three-dimensional model 310 have the same fill pattern, indicating that both are second layers of the respective particular three-dimensional model. The fill patterns of the three slice images are different to show the difference.

Referring to fig. 3A-3D, the specific three-dimensional model may be printed by performing a height positive compensation on the specific three-dimensional model located on the loading platform 120 and located at a position higher than the normal height, and the slice image at the bottom layer of the data model is printed by delaying one or more layers, so that the final height/thickness is equal to the height/thickness of the specific three-dimensional model located at the normal height.

It will be appreciated that fig. 3A-3D are merely examples, and that the particular number of layers that postpone the bottommost slice image depends on the difference between the height of the placement location at which the particular three-dimensional model is located and the normal height. For example, if the height of the arrangement position is n layers higher than the normal height, the bottommost slice image is printed after n layers, or the bottommost image may be copied for n layers of exposure. When n is not an integer, n is rounded and used.

Fig. 4A-4D are diagrams of the situation when the height compensation value for a particular three-dimensional model is negative. In the example shown in fig. 4A to 4D, the bottom surface 121 of the stage 120 is similarly inclined as compared with the example shown in fig. 3A to 3D, and the three specific three-dimensional models are set in the same manner and in the same number. The difference is that in the example shown in fig. 4A-4D, the height of the position to the left of the carrier table 120 is taken as the normal height of the carrier table 120. When three-dimensional printing is performed, the bottom layer of the three-dimensional model located on the left side of the bearing table 120 is printed first.

Referring to fig. 4A-4D, the arrangement positions of the fourth specific three-dimensional model 440, the fifth specific three-dimensional model 450, and the sixth specific three-dimensional model 460 are located at the left, the middle, and the right of the bottom surface 121 of the susceptor 120, respectively. If the height of the left side of the carrier table 120 is equal to the normal height of the carrier table 120, the height compensation value corresponding to the fourth specific three-dimensional model 440 is zero; if the height of the middle position of the carrier table 120 is lower than the normal height of the carrier table 120, the height compensation value corresponding to the fifth specific three-dimensional model 450 is a negative value; the height at the right side of the carrier table 120 is lower than the normal height of the carrier table 120, and is also lower than the height at the middle of the carrier table 120, so the height compensation value corresponding to the sixth specific three-dimensional model 460 is also negative. In the embodiment shown in fig. 4A to 4D, it is assumed that the height of the arrangement position at which the fifth specific three-dimensional model 450 is located is lower by one layer thickness than the normal height, and the height of the arrangement position at which the sixth specific three-dimensional model 460 is located is lower by two layer thicknesses than the normal height.

Let the thickness of one layer of printing resin be d. It is understood that if the fourth specific three-dimensional model 440, the fifth specific three-dimensional model 450, and the sixth specific three-dimensional model 460 are printed at the same time, due to the transmission of light, a three-dimensional model having a thickness d can be formed for the fourth specific three-dimensional model 440 while the first layer is printed. However, for both the fifth specific three-dimensional model 450 and the sixth specific three-dimensional model 460, the thickness of the layer of three-dimensional model formed is greater than d, and the thickness of the layer of the sixth specific three-dimensional model 460 is greater than the thickness of the layer of the fifth specific three-dimensional model 450. Therefore, in the three-dimensional printing, one or more slice images are removed from the bottom layer of the data model of the fifth specific three-dimensional model 450 and the sixth specific three-dimensional model 460, and the bottom layer of the fourth specific three-dimensional model 440 is printed first.

Fig. 4B is a step of performing three-dimensional printing in the case shown in fig. 4A. According to step 230, since the height compensation value of the fourth specific three-dimensional model 440 is zero, the number of slice image layers of the fourth specific three-dimensional model 440 to be printed can be kept constant. Then at the step shown in fig. 4B, the first layer slice image of the fourth particular three-dimensional model 440 is first printed using the image exposure system 140 in the three-dimensional printing device. The lowermost slice images of the data models of the fifth specific three-dimensional model 450 and the sixth specific three-dimensional model 460 are not printed, that is, one layer of slice images is first removed from the lowermost layer of the data models of the fifth specific three-dimensional model 450 and the sixth specific three-dimensional model 460.

Fig. 4C is a step after the printing step shown in fig. 4B. After the step shown in fig. 4B is completed, the carrier 120 of the three-dimensional printing apparatus drives the first layer of light-cured three-dimensional model to descend together, and the coating scraper 130 uniformly spreads a layer of liquid printing resin on the top surface of a layer of cured workpiece by moving, so as to be used for printing the next layer of three-dimensional model. Referring to fig. 4C, at this time, for the fourth specific three-dimensional model 440, the three-dimensional printing apparatus prints in accordance with the second layer cut image thereof. For the fifth specific three-dimensional model 450 located in the middle of the bottom surface 121 of the carrier 120, one layer of slice image needs to be removed from the lowest layer of the data model of the fifth specific three-dimensional model 450 according to the height compensation value, so that at this step, printing can be started on the fifth specific three-dimensional model 450, and the second layer of slice image from the lowest layer to the top in the original data model is printed. As shown in fig. 4C, the second layer slice image of the fifth specific three-dimensional model 450 has the same fill pattern as the second layer slice image of the fourth specific three-dimensional model 440, indicating that both are the second layers of the respective specific three-dimensional models.

Fig. 4D is a step subsequent to the printing step shown in fig. 4C. Similar to the step shown in fig. 4C, after the step shown in fig. 4C is completed, the carrier 120 of the three-dimensional printing apparatus drives the first two layers of the light-cured fourth specific three-dimensional model 440 and the second layer of the fifth specific three-dimensional model 450 to descend together, and the coating blade 130 uniformly spreads a layer of liquid printing resin on the top surface of the cured workpiece by moving, so as to be used for printing the next layer of three-dimensional model. Referring to fig. 4D, at this time, for the fourth specific three-dimensional model 440, the three-dimensional printing apparatus prints in accordance with the third layer slice image thereof; for the fifth particular three-dimensional model 450, the three-dimensional printing device prints according to its third layer slice image. For the sixth specific three-dimensional model 460 located at the right side of the bottom surface 121 of the carrier 120, two layers of slice images need to be removed from the lowest layer of the data model of the sixth specific three-dimensional model 460 according to the height compensation value, so that at this step, printing can be started on the sixth specific three-dimensional model 460, and the third layer of slice images from the lowest layer to the top in the original data model is printed. As shown in fig. 4D, the third layer slice image of the sixth specific three-dimensional model 460, the third layer slice image of the fourth specific three-dimensional model 440, and the third layer slice image of the fifth specific three-dimensional model 450 have the same fill pattern, which indicates that all three are the third layer of the respective specific three-dimensional models. Similarly, the second layer slice image of the fifth particular three-dimensional model 450 and the second layer slice image of the fourth particular three-dimensional model 440 have the same fill pattern, indicating that both are second layers of the respective particular three-dimensional models. The fill patterns of the three slice images are different to show the difference.

By printing the specific three-dimensional model according to the steps shown in fig. 4A-4D, the specific three-dimensional model positioned on the carrier 120 at a position lower than the normal height may be subjected to height negative compensation, and one or more slice images are removed from the bottom layer of the data model, so that the final height/thickness is equal to the height/thickness of the specific three-dimensional model positioned at the normal height.

FIGS. 5A-5C are another embodiment of printing a particular three-dimensional model when the height compensation value for the particular three-dimensional model is a negative value. In this embodiment, the bottom surface 121 of the carrier 120 shown in fig. 5A is the same as that of fig. 4A. The specific three-dimensional models and the arrangement positions thereof are also the same, including a fourth specific three-dimensional model 440, a fifth specific three-dimensional model 450, and a sixth specific three-dimensional model 460. Similarly, it is assumed that the height of the arrangement position where the fourth specific three-dimensional model 440 is located is a normal height, the height of the arrangement position where the fifth specific three-dimensional model 450 is located is lower than the normal height by one layer thickness, and the height of the arrangement position where the sixth specific three-dimensional model 460 is located is lower than the normal height by two layer thicknesses.

In the present embodiment, one layer of slice images is removed from the lowermost layer of the fifth specific three-dimensional model 450 in advance, and two layers of slice images are removed from the lowermost layer of the data model of the sixth specific three-dimensional model 460.

Referring to fig. 5A, at the start of printing, three specific three-dimensional models are printed simultaneously using the image exposure system 140 in the three-dimensional printing apparatus. Wherein the first layer slice image of the fourth specific three-dimensional model 440 is printed, the second layer slice image of the fifth specific three-dimensional model 450 is printed, and the third layer slice image of the sixth specific three-dimensional model 460 is printed. Due to the transparency of the curing light, although printing is performed only on the basis of one slice image, the thickness of the obtained printed model is different for each specific three-dimensional model. Specifically, if the thickness of one layer of printing resin is d, the thicknesses of the three-dimensional models obtained corresponding to the fourth specific three-dimensional model 440, the fifth specific three-dimensional model 450, and the sixth specific three-dimensional model 460 through the printing of this step are d, 2d, and 3d, respectively.

Referring to fig. 5B, after the printing of fig. 5A, the second layer slice image of the fourth specific three-dimensional model 440, the third layer slice image of the fifth specific three-dimensional model 450, and the fourth layer slice image of the sixth specific three-dimensional model 460 are printed. Wherein the second layer slice image of the fourth particular three-dimensional model 440 and the second layer slice image of the fifth particular three-dimensional model 450 have the same fill pattern, indicating that both are second layers of the respective particular three-dimensional model.

Referring to fig. 5C, after the printing of fig. 5B, the third layer slice image of the fourth specific three-dimensional model 440, the fourth layer slice image of the fifth specific three-dimensional model 450, and the fifth layer slice image of the sixth specific three-dimensional model 460 are printed. The third layer slice image of the fourth specific three-dimensional model 440, the third layer slice image of the fifth specific three-dimensional model 450, and the third layer slice image of the sixth specific three-dimensional model 460 have the same filling pattern, which indicates that all three layers are the third layer of the respective specific three-dimensional models.

As shown in fig. 5A-5C, the fourth specific three-dimensional model 440, the fifth specific three-dimensional model 450, and the sixth specific three-dimensional model 460 are printed in sequence until printing is completed.

It is understood that the illustrations of fig. 3A-3D, 4A-4D, and 5A-5C are merely examples illustrating the unevenness of the bottom surface 121 of the carrier 120. The unevenness of the bottom surface 121 of the susceptor 120 may be any other unevenness. Under different conditions, a position on the bottom surface 121 of the carrier 120 may be designated as a normal height, and based on the normal height, a positive height compensation value may be determined for a specific three-dimensional model located at a position higher than the normal height, and a negative height compensation value may be determined for a specific three-dimensional model located at a position lower than the normal height, and printing may be performed by referring to the three-dimensional printing method of the present invention, so that height compensation may be performed on the specific three-dimensional model on the carrier, respectively, to obtain specific three-dimensional models of the same height/thickness.

In embodiments of the present invention, the printing resin may be a liquid photosensitive resin or a liquid photosensitive resin to which an additional component is added.

The present invention also includes a three-dimensional printing apparatus adapted to print a three-dimensional model, the three-dimensional printing apparatus including a printing mechanism and a controller. The controller is configured to control the printing mechanism to perform the three-dimensional printing method as described above. The controller may be, for example, a computing device such as a personal computer, an embedded computer, or the like.

The invention also includes a computer readable medium having stored thereon computer program code which, when executed by a processor, may implement a three-dimensional printing method as described above.

The order of processing elements and sequences, the use of alphanumeric characters, or other designations in the present application is not intended to limit the order of the processes and methods in the present application, unless otherwise specified in the claims. While various presently contemplated embodiments of the invention have been discussed in the foregoing disclosure by way of example, it is to be understood that such detail is solely for that purpose and that the appended claims are not limited to the disclosed embodiments, but, on the contrary, are intended to cover all modifications and equivalent arrangements that are within the spirit and scope of the embodiments herein.

This application uses specific words to describe embodiments of the application. Reference throughout this specification to "one embodiment," "an embodiment," and/or "some embodiments" means that a particular feature, structure, or characteristic described in connection with at least one embodiment of the present application is included in at least one embodiment of the present application. Therefore, it is emphasized and should be appreciated that two or more references to "an embodiment" or "one embodiment" or "an alternative embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, some features, structures, or characteristics of one or more embodiments of the present application may be combined as appropriate.

Aspects of the methods and systems of the present application may be performed entirely by hardware, entirely by software (including firmware, resident software, micro-code, etc.), or by a combination of hardware and software. The above hardware or software may be referred to as "data block," module, "" engine, "" unit, "" component, "or" system. The processor may be one or more Application Specific Integrated Circuits (ASICs), Digital Signal Processors (DSPs), digital signal processing devices (DAPDs), Programmable Logic Devices (PLDs), Field Programmable Gate Arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, or a combination thereof. Furthermore, aspects of the present application may be represented as a computer product, including computer readable program code, embodied in one or more computer readable media. For example, computer-readable media can include but are not limited to magnetic storage devices (e.g., hard disk, floppy disk, magnetic strips … …), optical disks (e.g., Compact Disk (CD), Digital Versatile Disk (DVD) … …), smart cards, and flash memory devices (e.g., card, stick, key drive … …).

A computer readable signal medium may comprise a propagated data signal with computer program code embodied therein, for example, on a baseband or as part of a carrier wave. The propagated signal may take any of a variety of forms, including electromagnetic, optical, and the like, or any suitable combination. A computer readable signal medium may be any computer readable medium that is not a computer readable storage medium and that can communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device. Program code on a computer readable signal medium may be propagated over any suitable medium, including radio, electrical cable, fiber optic cable, radio frequency signals, or the like, or any combination of the preceding.

Additionally, the order in which elements and sequences of the processes described herein are processed, the use of alphanumeric characters, or the use of other designations, is not intended to limit the order of the processes and methods described herein, unless explicitly claimed. While various presently contemplated embodiments of the invention have been discussed in the foregoing disclosure by way of example, it is to be understood that such detail is solely for that purpose and that the appended claims are not limited to the disclosed embodiments, but, on the contrary, are intended to cover all modifications and equivalent arrangements that are within the spirit and scope of the embodiments herein. For example, although the system components described above may be implemented by hardware devices, they may also be implemented by software-only solutions, such as installing the described system on an existing server or mobile device.

Similarly, it should be noted that in the preceding description of embodiments of the application, various features are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure aiding in the understanding of one or more of the embodiments. This method of disclosure, however, is not intended to require more features than are expressly recited in the claims. Indeed, the embodiments may be characterized as having less than all of the features of a single embodiment disclosed above.

Numerals describing the number of components, attributes, etc. are used in some embodiments, it being understood that such numerals used in the description of the embodiments are modified in some instances by the use of the modifier "about", "approximately" or "substantially". Unless otherwise indicated, "about", "approximately" or "substantially" indicates that the number allows a variation of ± 20%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximations that may vary depending upon the desired properties of the individual embodiments. In some embodiments, the numerical parameter should take into account the specified significant digits and employ a general digit preserving approach. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the range are approximations, in the specific examples, such numerical values are set forth as precisely as possible within the scope of the application.

Although the present invention has been described with reference to the present specific embodiments, it will be appreciated by those skilled in the art that the above embodiments are merely illustrative of the present invention, and various equivalent changes and substitutions may be made without departing from the spirit of the invention, and therefore, changes and modifications to the above embodiments within the spirit of the invention are intended to fall within the scope of the claims of the present application.