Three-dimensional printing system and method for three-dimensional printing

1. A printing system, comprising:

a light source unit, configured to illuminate a target object;

at least one image-capturing module, comprising:

an image-capturing unit, disposed at a side of the target object;

and a focus-adjusting lens group, disposed between the image-capturing unit and the target object;

a processing unit, controlling the focus-adjusting lens group to change shooting focal lengths and controlling the image-capturing unit to capture a plurality of images of the target object under the different shooting focal lengths, wherein each of the plurality of images comprises a focused local image and an unfocused local image therein, and the processing unit calculates a three-dimensional profile data of the target object by arranging the focused local images among the images based on the shooting focal lengths corresponding to the focused local images;

and

a printing device, printing a plurality of cross-sectional profiles of the target object according to the three-dimensional profile data, wherein the processing unit maps the three-dimensional profile data to a driving unit of the printing device by respectively mapping the focused local images among the images of the target object captured by the image-capturing unit under the different shooting focal lengths to the driving unit of the printing device, and the driving unit drives the printing device to print out, layer by layer, the plurality of cross-sectional profiles of the target object in a cumulative and stacked manner according to the mapped corresponding focused local images among the images.

2. The three-dimensional printing system as claimed in claim 1 , wherein the light source unit provides the target object with an illumination light, the target object is opaque relatively to the illumination light, the focused local images are images of overlapped portions of the target object and a plurality of focus planes under the different shooting focal lengths, where the three-dimensional profile data comprises an information of a surface profile of the target object.

3. The three-dimensional printing system as claimed in claim 2 , wherein the image-capturing module shoots the target object with at least one shooting optical axis, a minimal value of the shooting focal lengths is a shortest distance between the focus-adjusting lens group and the target object along the shooting optical axis, and a maximal value of the shooting focal lengths is a distance between the focus-adjusting lens group and the focus plane along the shooting optical axis when an overlapped cross-section area of the target object and the focus plane is maximal.

4. The three-dimensional printing system as claimed in claim 1 , wherein the light source unit provides the target object with an illumination light, the target object is transparent relatively to the illumination light, the focused local images are images of overlapped portions of the target object and a plurality of focus planes under the different shooting focal lengths, where the three-dimensional profile data comprises an information of a surface profile and an inner shape of the target object.

5. The three-dimensional printing system as claimed in claim 4 , wherein the image-capturing module shoots the target object with at least one shooting optical axis, a minimal value of the shooting focal lengths is a shortest distance between the focus-adjusting lens group and the target object along the shooting optical axis, and a maximal value of the shooting focal lengths is a longest distance between the focus-adjusting lens group and the target object along the shooting optical axis.

6. The three-dimensional printing system as claimed in claim 1 , wherein the at least one image-capturing module comprises a plurality of image-capturing modules respectively disposed surrounding the target object, wherein the plurality of image-capturing modules respectively capture at least a portion of the images of the target object with different shooting optical axes.

7. The three-dimensional printing system as claimed in claim 1 , wherein the driving unit performs image scaling and printing according to the focused local images among the mapped images.

8. A method for three-dimensional printing, comprising:

illuminating a target object with a light source unit;

controlling a focus-adjusting lens group, disposed between the image-capturing unit and the target object, to change shooting focal lengths

and controlling an image-capturing unit disposed at a side of the target object to capture a plurality of images of the target object under different shooting focal lengths by at least one shooting optical axis, wherein each of the images comprises a focused local image and an unfocused local image;

calculating a three-dimensional profile data of the target object by arranging the focused local images in the images based on the shooting focal lengths corresponding to the focused local images;

and

printing a plurality of cross-sectional profiles of the target object according to the three-dimensional profile data, wherein the processing unit maps the three-dimensional profile data to a driving unit of the printing device by respectively mapping the focused local images among the images of the target object captured by the image-capturing unit under the different shooting focal lengths to the driving unit of the printing device, and the driving unit drives the printing device to print out, layer by layer, the plurality of cross-sectional profiles of the target object in a cumulative and stacked manner according to the mapped corresponding focused local images among the images.

9. The method for three-dimensional printing as claimed in claim 8 , wherein:

the target object is opaque relatively to the illumination light illuminating the target object, the focused local images are images of overlapped portions of the target and a plurality of focus planes under the different shooting focal lengths, where the three-dimensional profile data comprises an information of a surface profile of the target object.

10. The method for three-dimensional printing as claimed in claim 9 , wherein the step of capturing the plurality of images of the target object under the different shooting focal lengths further comprises:

shooting the target object with at least one shooting optical axis through the image-capturing module, a minimal value of the shooting focal lengths is a shortest distance between the focus-adjusting lens group of the image-capturing module and the target object along the shooting optical axis, and a maximal value of the shooting focal lengths is a distance between the focus-adjusting lens group and the focus plane along the shooting optical axis when an overlapped cross-section area of the target object and the focus plane is maximal.

11. The method for three-dimensional printing as claimed in claim 8 , wherein:

the target object is transparent relatively to the illumination light illuminating the target object, the focused local images are images of overlapped portions of the target object and a plurality of focus planes under the different shooting focal lengths, and the three-dimensional profile data comprises an information of a surface profile and an inner shape of the target object.

12. The method for three-dimensional printing as claimed in claim 11 , wherein the step of capturing the plurality of images of the target object under the different shooting focal lengths further comprises:

shooting the target object with at least one shooting optical axis through the image-capturing module, a minimal value of the shooting focal lengths is a shortest distance between the focus-adjusting lens group of the image-capturing module and the target object along the shooting optical axis, and a maximal value of the shooting focal lengths is a longest distance between the focus-adjusting lens group and the target object along the shooting optical axis.

13. The method for three-dimensional printing as claimed in claim 8 , wherein the driving unit performs image scaling and printing according to the mapped focused local images among the images.