TWI459039B - Apparatus and method for transforming a laser beam - Google Patents

Description

Laser beam conversion device and method

The present invention relates to a laser beam converting device and method, and more particularly to converting a main laser beam into a first laser beam having a first polarization direction and having a second polarization direction. A second laser beam and a device and method for focusing it on a first focus and a second focus, respectively.

With the advancement of technology, the mainstream trend of various technology products has gradually developed in a light, short and short direction. The traditional processing techniques, such as die stamping, drilling and cutting, are limited by their precision. The traits are no longer able to meet the needs of the general industry and the expectations of consumers. In contrast, lasers have the characteristics of monochromaticity, low divergence, high energy density and high coherence, which give laser processing technology such as high processing density, finer work and can be performed. Advantages such as non-contact processing. Furthermore, laser processing technology has been widely used in many industries today, and has gradually replaced traditional processing methods.

However, even though the laser processing technology used in the industry today is quite mature, there are still limitations. For example, when laser processing and measurement operations are currently performed on materials, it is often necessary to design according to different designs. Setting different focal positions on the area, or repeating at least two or more laser processing scanning steps on different thicknesses, especially when the thickness or surface of the workpiece has a large numerical change, the multiple is increased. Repeating the number of times of laser scanning, therefore, due to the increase in the number of scanning steps of the aforementioned laser processing, the processing time is more tedious, resulting in a decrease in production efficiency and a further extension of the repeated scanning. The problem of positioning offset when tracing.

Therefore, how to provide a laser beam conversion device and method, so that a single laser beam incident can form a secondary laser beam with different difocal points, thereby improving production efficiency and processing quality, which is in need of common industry The goal of hard work.

It is an object of the present invention to provide a laser beam conversion device that allows a single main laser beam to form a secondary laser beam having distinct difocal points, thereby reducing the number of scans required for laser processing. Further improve production efficiency.

Another object of the present invention is to provide a laser beam conversion device capable of separately adjusting the energy of a secondary laser beam and a focus position, so that different difocalities can be performed for the same material or surface according to different processing requirements. Laser processing and measurement operations.

To achieve the above objective, the laser beam conversion device of the present invention comprises a polarization deflection element, a beam splitting component, a first optical module, a second optical module and a third optical module. Wherein the polarization deflecting element is configured to receive a main laser beam and convert it into a first laser beam having a first polarization direction and a second laser beam having a second polarization direction After injection into the beam splitting element. The first laser beam having the first polarization direction is adapted to penetrate the beam splitting element and is focused by a third optical module to a first focus. After the second laser beam having the second polarization direction is reflected by the beam splitting element, it is sequentially converted and reflected by the first optical module and the second optical module, and finally, after being reflected by the beam splitting element, by the third The optical module focuses on a second focus that is different from the first focus.

The above objects, technical features, and advantages will be more apparent from the following description.

Fig. 1 is a perspective view showing a laser beam converting device 1 of the present invention. As shown, when a main laser beam 2 is incident on the laser beam converting device 1, it will be reflected and converted by the internal components of the laser beam converting device 1 to have a first polarization direction P. a laser beam 21 and a second laser beam 22 having a second polarization direction S are emitted, and a first focus 81 is formed on a workpiece 8 and is different from the first focus 81. The two focal points 82 perform laser processing operations for different bifocal surfaces on the surface of the workpiece 8, thereby improving production efficiency.

As shown in the first embodiment of FIG. 2, the laser beam conversion device 1 of the present invention comprises a polarization deflection element 3, a beam splitting element 4, a first optical module 5, a second optical module 6, and A third optical module 7. In the embodiment, the first optical module 5 is disposed opposite to the second optical module 6 , and the third optical module 7 is disposed opposite to the polarization deflecting element 3 . Further, the spectroscopic element 4 of the present invention has a characteristic of allowing a laser beam having a first polarization direction P to penetrate and reflecting a laser beam having a second polarization direction S.

In this embodiment, the first optical module 5 preferably includes a first-time polarization deflecting element 51 and a first reflective element 52, and the second optical module 6 preferably includes a second The sub-polarized deflection element 61, a second reflective element 62 and a first lens 63, and the third optical module 7 is preferably a second lens 71. Wherein, the first polarization deflecting element 51 has a laser beam having a second polarization direction S converted into a laser beam having a first polarization direction P, and allows a lightning having a first polarization direction P The characteristics of the beam penetration. Similarly, the second polarization deflecting element 61 has a laser beam that converts a laser beam having a first polarization direction P into a laser beam having a second polarization direction S, and allows laser beam penetration with a second polarization direction S Characteristics.

The beam travel route for the first laser beam 21 having the first polarization direction P and the second laser beam 22 having the second polarization direction S will be described below.

Referring again to FIG. 2, first, when the first laser beam 21 having the first polarization direction P is incident on the beam splitting element 4, since the beam splitting element 4 allows the laser beam having the first polarization direction P to pass, The first laser beam 21 having the first polarization direction P is adapted to penetrate the beam splitting element 4 and is focused on the workpiece 8 by the action of the third optical module 7 (ie, the second lens 71). A focus of 81.

At the same time, when the second laser beam 22 having the second polarization direction S is incident on the beam splitting element 4, since the beam splitting element 4 reflects the laser beam having the second polarization direction S, it has the second polarization direction. The second laser beam 22 of S is adapted to be reflected by the beam splitting element 4 and then enters the first optical module 5. Thereafter, the second laser beam 22 having the second polarization direction S converts the first polarization deflection element 51 of the first optical module 5 into a second laser beam 23 having a first polarization direction P. And being reflected by the first reflective element 52 of the first optical module 5, sequentially injecting and penetrating the first polarization deflecting element 51 and the beam splitting element 4, and reaching the first setting with respect to the first optical module 5 Two optical modules 6. Next, the second laser beam 23 having the first polarization direction P will pass through the first lens 63 of the second optical module 6, and the second polarization deflection element 61 of the second optical module 6 is suitable. Converting the second laser beam 23 having the first polarization direction P into a second laser having the second polarization direction S again The light beam 22 is reflected by the second reflective element 62 of the second optical module 6, and sequentially enters and penetrates the second polarization deflecting element 62 and the first lens 63 to reach the light splitting element 4. Finally, the beam splitting element 4 will again reflect the second laser beam 22 having the second polarization direction S, and focus it on the first focus 81 by the third optical module 7 (ie, the second lens 71). The second focus 82 is different, thereby accomplishing the purpose of the present invention for converting a single main laser beam 2 into a secondary laser beam having a two-phase different focus.

In the embodiment, the first lens 63 disposed on the second optical module 6 is used to change the diffusion angle of the incident second laser beam 22. Thereby, the two different laser beams will have different divergence angles due to the difference in the number of lenses passed, and further two focal points having different horizontal positions can be formed on the workpiece 8. In addition, if the polarization deflecting element 3 is rotated, it is also possible to assist in adjusting the energy ratio between the first laser beam 21 having the first polarization direction P and the second laser beam 22 having the second polarization direction S. Control the depth of laser processing.

As shown in Fig. 3, it is a schematic view of a second embodiment of the present invention. The arrangement of the components of the second embodiment is basically similar to that of the first embodiment, and includes the polarization deflecting element 3, the beam splitting component 4, the first optical module 5, the second optical module 6, and the first Three optical modules 7 and other components. Similarly, the first optical module 5 is disposed opposite to the second optical module 6, and the third optical module 7 is disposed opposite to the polarization deflecting element 3. The second embodiment is different from the first embodiment in that the first polarization deflecting element 51 and the first reflective element 52 originally included in the first optical module 5 of the first embodiment are The third polarization deflection element 53 is replaced, and the second polarization deflection element 61 and the second reflection originally disposed in the second optical module 6 are replaced. Element 62 is replaced by a fourth polarization deflection element 64. In this way, the third polarization deflecting element 53 will also have the second laser beam 22 having the second polarization direction S converted into the second laser beam 23 having the first polarization direction P and then reflected. The fourth polarization polarization element 64 also has the function of converting the second laser beam 23 having the first polarization direction P into the second laser beam 22 having the second polarization direction S and reflecting it. .

Accordingly, since the number of components disclosed in the second embodiment is smaller than that of the first embodiment, it will contribute to reducing the volume of the laser beam converting device 1 for more precise laser positioning operation.

Figure 4 is a schematic view of a third embodiment of the present invention. Similarly to the first embodiment, the laser beam conversion device 1 includes elements such as a polarization deflecting element 3, a beam splitting element 4, a first optical module 5, a second optical module 6, and a third optical module 7. However, the difference in the first embodiment is that the first optical module 5 disclosed in the third embodiment is disposed opposite to the third optical module 7, and the second optical module 6 is coupled to the polarization deflecting element 3. Relative settings. In addition, since the preferred embodiments of the components of the third embodiment are the same as those of the first embodiment, the functions of the components are not described herein.

The beam travel route in the third embodiment will be described below with respect to the first laser beam 21 having the first polarization direction P and the second laser beam 22 having the second polarization direction S.

As shown in FIG. 4, first, when the first laser beam 21 having the first polarization direction P is incident on the beam splitting element 4, since the beam splitting element 4 allows the laser beam having the first polarization direction P to pass, The first laser beam 21 having the first polarization direction P is adapted to penetrate the beam splitting element 4 and arrive opposite to the polarization deflecting element 3 A second optical module 6 is provided. Then, the first laser beam 21 having the first polarization direction P will pass through the first lens 63 of the second optical module 6, and the second polarization deflection element 61 of the second optical module 6 will be suitable. The first laser beam 21 having the first polarization direction P is converted into the first laser beam 24 having the second polarization direction S, and is reflected by the second reflection element 62 of the second optical module 6, and The second polarization deflecting element 62 is incident on and penetrates the first lens 63 and reaches the beam splitting element 4. Thereafter, the beam splitting element 4 will reflect the first laser beam 24 having the second polarization direction S and focus it on the first focus 81 of the object 8 by the third optical module 7 (i.e., the second lens 71).

At the same time, when the second laser beam 22 having the second polarization direction S is incident on the beam splitting element 4, since the beam splitting element 4 reflects the laser beam having the second polarization direction S, it has the second polarization direction S. The second laser beam 22 is adapted to be reflected by the beam splitting element 4 and then into the first optical module 5. Thereafter, the second laser beam 22 having the second polarization direction S converts the first polarization deflection element 51 of the first optical module 5 into a second laser beam 23 having a first polarization direction P. And being reflected by the first reflective element 52 of the first optical module 5, sequentially incident and penetrating the first polarization deflecting element 51 and the beam splitting element 4, and by the third optical module 7 (ie, the second The lens 71) focuses it on a second focus 82 that is different from the first focus 81, thereby accomplishing the object of the present invention for converting a single main laser beam 2 into a secondary laser beam having distinct difocal points.

Moreover, in order to further reduce the volume of the laser beam conversion device 1, the third polarization polarization element 53 may be used to replace the first polarization deflection element 51 and the first reflection element originally disposed in the first optical module 5. 52, and the fourth polarization deflection element The member 64 replaces the second-order polarization deflecting element 61 and the second reflecting element 62 which are originally disposed in the second optical module 6, so that it becomes the fourth embodiment as shown in Fig. 5. In addition, since the beam travel route of the fourth embodiment is the same as the third embodiment, it will not be described here.

In the present invention, the main laser beam 2 is a laser beam having a single polarization direction, the polarization deflection element 3 is a 1/2 wave plate or other equivalent element, and the first polarization deflection element 51 and The second polarization deflection element 61 is a transmissive polarization deflection element such as a 1/4 slide or other equivalent element. At the same time, the third polarization deflection element 53 and the fourth polarization deflection element 64 are reflective polarization deflection elements, such as polarization rotating mirrors or other equivalent components. The first reflective element 52 and the second reflective element 62 are mirrors or other equivalent elements, and the splitting element 4 is a polarizing beam splitter.

As shown in FIG. 6, when the first optical module 5 is disposed opposite to the second optical module 6, and the third optical module 7 is disposed opposite to the polarization deflecting element 3, the laser beam conversion of the present invention The method has the following steps: as shown in step 901, the main laser beam 2 is converted by the polarization deflecting element 3 into a first laser beam 21 having a first polarization direction P and a second beam having a second polarization direction S. Secondary laser beam 22. Next, as shown in step 902, the first laser beam 21 having the first polarization direction P is passed through the beam splitting element 4 and directly focused by the third optical module 7 to the first focus 81. Finally, as shown in step 903, the second laser beam 22 having the second polarization direction S is subjected to two conversion steps and four reflection steps inside the laser beam conversion device 1 by the third optical mode. Group 7 focuses on a second focus 82 that is different from first focus 81.

As shown in FIG. 7, when the first optical module 5 is opposite to the third optical module 7, When the second optical module 6 is disposed opposite to the polarization deflecting element 3, the laser beam converting method of the present invention has the following steps: as shown in step 901, the main laser beam 2 is polarized by the polarizing element 3 is converted into a first laser beam 21 having a first polarization direction P and a second laser beam 22 having a second polarization direction S. Then, as shown in step 904, the first laser beam 21 having the first polarization direction P is subjected to a conversion step and a double reflection step inside the laser beam conversion device 1 by the third optical module 7 Focus on the first focus 81. Then, as shown in step 905, the second laser beam 22 having the second polarization direction S is subjected to a conversion step and a double reflection step inside the laser beam conversion device 1 by the third optical module. 7 focuses on a second focus 82 that is different from the first focus 81.

In summary, the present invention is characterized in that a secondary laser beam having a different difocal point can be obtained by injecting a single main laser beam into the laser beam conversion device of the present invention to target the same object. Processing and measuring operations of different thicknesses or surfaces. In other words, when the laser beam converting device 1 of the present invention has the first embodiment shown in FIG. 2 and the second embodiment shown in FIG. 3, the main laser beam 2 is formed. A secondary laser beam having a first polarization direction P and a second polarization direction S is transmitted in the laser beam conversion device 1. At this time, the secondary laser beam having the first polarization direction P will directly penetrate the beam splitting element 4 and enter the third optical module 7 to be focused on the first focus 81. Moreover, the secondary laser beam having the second polarization direction S is subjected to two conversion steps and four reflection steps in the laser beam conversion device 1, and then incident on the third optical module 7 to be focused on the second focus 82. .

On the other hand, when the laser beam converting device 1 of the present invention has the image as shown in FIG. In the third embodiment shown in the third embodiment and the fifth embodiment, the second laser beam having the first polarization direction P and the second polarization direction S formed by the main laser beam 2 will be Ray The beam conversion device 1 transmits the same. At this time, the second laser beam is subjected to a conversion step and a reflection step twice in the laser beam conversion device 1, and then enters the third optical module 7 and respectively Focusing on the first focus 81 and the second focus 82, thereby achieving the purpose of reducing the number of scans in the laser processing of the present invention while improving production efficiency.

Furthermore, the first polarization direction and the second polarization direction of the present invention are not limited to have the aforementioned state. In other words, the first polarization direction and the second polarization direction may be respectively the P polarization direction and the S polarization direction, and the two polarization directions may be mutually exchanged to make the S polarization direction and the P polarization direction respectively. The result of the invention has an impact.

The embodiments described above are only intended to illustrate the embodiments of the present invention, and to explain the technical features of the present invention, and are not intended to limit the scope of protection of the present invention. Any changes or equivalents that can be easily made by those skilled in the art are within the scope of the invention. The scope of the invention should be determined by the scope of the claims.

1‧‧‧Laser beam conversion device

2‧‧‧Main laser beam

21‧‧‧First laser beam with first polarization direction P

22‧‧‧Second laser beam with second polarization direction S

23‧‧‧Second laser beam with first polarization direction P

24‧‧‧First laser beam with second polarization direction S

3‧‧‧Polarized deflection element

4‧‧‧Spectral components

5‧‧‧First optical module

51‧‧‧First Polarization Deflection Element

52‧‧‧First reflective element

53‧‧‧ Third Polarization Deflection Element

6‧‧‧Second optical module

61‧‧‧Second polarization deflection element

62‧‧‧Second reflective element

63‧‧‧First lens

64‧‧‧ Fourth Polarization Deflection Element

7‧‧‧ Third optical module

71‧‧‧second lens

8‧‧‧Workpiece

81‧‧‧ first focus

82‧‧‧second focus

1 is a schematic perspective view of a laser beam conversion device of the present invention; FIG. 2 is a schematic view of a first embodiment of a laser beam conversion device of the present invention; and FIG. 3 is a second embodiment of the laser beam conversion device of the present invention. FIG. 4 is a schematic view showing a third embodiment of the laser beam conversion device of the present invention; FIG. 5 is a schematic view showing a fourth embodiment of the laser beam conversion device of the present invention; And Figures 6 and 7 are diagrams showing the steps of converting a primary laser beam into a secondary laser beam having different difocal points according to the present invention.

1‧‧‧Laser beam conversion device

2‧‧‧Main laser beam

21‧‧‧First laser beam with first polarization direction P

22‧‧‧Second laser beam with second polarization direction S

23‧‧‧Second laser beam with first polarization direction P

3‧‧‧Polarized deflection element

4‧‧‧Spectral components

5‧‧‧First optical module

51‧‧‧First Polarization Deflection Element

52‧‧‧First reflective element

6‧‧‧Second optical module

61‧‧‧Second polarization deflection element

62‧‧‧Second reflective element

63‧‧‧First lens

7‧‧‧ Third optical module

71‧‧‧second lens

Claims (19)

A laser beam conversion device includes: a polarization deflection element for receiving a main laser beam and converting it into a first laser beam having a first polarization direction and having a second polarization direction a second laser beam; a beam splitting element for receiving the first laser beam and the second laser beam from the polarization deflecting element, and allowing the first first polarization direction The second laser beam penetrates and reflects the second laser beam having the second polarization direction; a first optical module includes a first polarization polarization element and a first reflection element, and the first An optical module is disposed adjacent to a first side of the light splitting element to receive and reflect the second laser beam; a second optical module includes a first lens and a second polarization deflection And a second reflective component disposed adjacent to a second side of the light splitting component to receive and reflect the first laser beam and the second laser beam And a third optical module disposed adjacent to the optical splitter a third side edge; wherein the first polarization deflecting element and the second polarization deflecting element are both transmissive polarization deflecting elements, and the first reflective element and the second reflective element are All of the mirrors, the first laser beam having the first polarization direction passes through the beam splitting element, and the second laser beam having the second polarization direction passes through the beam splitting element, the first optical module After the conversion of the second optical module and the third optical module, respectively, it is suitable to respectively focus on one of the first first focus and the second focus. The laser beam conversion device of claim 1, wherein the first side is opposite to the second side. The laser beam conversion device of claim 2, wherein the first laser beam having the first polarization direction is adapted to be incident on the third optical module after penetrating the beam splitting element. The laser beam conversion device of claim 3, wherein the first optical module, after receiving the second laser beam having the second polarization direction, is adapted to convert the first polarization direction to have the first polarization direction The second laser beam passes through the beam splitting element and is incident on the second optical module. The laser beam conversion device of claim 4, wherein the second optical module is adapted to convert the second laser beam to have the second polarization direction after receiving the second laser beam having the first polarization direction The second laser beam is reflected to the beam splitting element. The laser beam conversion device of claim 5, wherein the beam splitting element is adapted to receive the second laser beam from the second optical module having the second polarization direction The third optical module is injected. The laser beam conversion device of claim 1, wherein the first side and the second side are adjacent. The laser beam conversion device of claim 7, wherein the first laser beam having the first polarization direction is adapted to be incident on the second optical module after penetrating the beam splitting element. The laser beam conversion device of claim 8, wherein the second optical module is adapted to convert the first laser beam having the first polarization direction to have the second polarization direction The first laser beam, and the reflection To the spectroscopic element. The laser beam conversion device of claim 9, wherein the beam splitting element is adapted to receive the first laser beam from the second optical module having the second polarization direction The third optical module is injected. The laser beam conversion device of claim 10, wherein the first optical module, after receiving the second laser beam having the second polarization direction, is adapted to convert the first polarization direction to have the first polarization direction The second laser beam passes through the beam splitting element and is incident on the third optical module. The laser beam conversion device of claim 1, wherein the polarization deflection element is a transmissive polarization deflection element, and the third optical module is a lens. The laser beam conversion device of claim 1, wherein the main laser beam is a laser pulse beam having a single polarization direction, and the first polarization direction and the second polarization direction are respectively P polarization directions and S polarization direction, and the beam splitting element is a polarization beam splitter. A method for converting a laser beam, the laser beam conversion device according to claim 1, comprising the steps of: (a) converting a main laser beam to have a first polarization direction for the first time a laser beam and a second laser beam having a second polarization direction; (b) focusing the first laser beam having the first polarization direction to a first focus; and (c) having The second laser beam of the second polarization direction is focused on a second focus that is different from the first focus. The method of claim 14, wherein the step (b) further comprises: directly focusing the first laser beam having the first polarization direction on The first focus. The method of claim 15, wherein the step (c) further comprises: focusing the second laser beam having the second polarization direction after two conversion steps and four reflection steps, focusing on the first Two focus. The method of claim 14, wherein the step (b) further comprises: focusing the first laser beam having the first polarization direction, after one conversion step and two reflection steps, focusing on the first focus. The method of claim 17, wherein the step (c) further comprises: focusing the second laser beam having the second polarization direction, after one conversion step and two reflection steps, focusing on the second focus . A laser beam conversion device includes: a polarization deflection element for receiving a main laser beam and converting it into a first laser beam having a first polarization direction and having a second polarization direction a second laser beam; a beam splitting element for receiving the first laser beam and the second laser beam from the polarization deflecting element, and allowing the first first polarization direction The second laser beam penetrates and reflects the second laser beam having the second polarization direction; a first optical module includes a third polarization polarization element, and the first optical module is adjacent The first optical side of the light splitting element is configured to receive and reflect the second laser beam; the second optical module comprises a first lens and a fourth time polarized deflection element, and the second An optical module is disposed adjacent to a second side of the light splitting element to receive and reflect the first laser beam and the second laser beam And a third optical module disposed adjacent to a third side of the light splitting component; wherein the third polarized deflecting component and the fourth polarized deflecting component are reflective a polarization deflecting element, the first laser beam having the first polarization direction passing through the beam splitting element, and the second laser beam having the second polarization direction passing through the beam splitting element, the first optical module After the conversion of the second optical module and the third optical module, respectively, it is suitable to respectively focus on one of the first first focus and the second focus.