KR-20260067314-A - ULTRA SHORT PULSE WIDTH COMPRESSION DEVICE BASED ON SPECTRUM EXPANSION, FEMTOSECOND FIBER LASER SYSTEM INCLUDING THE SAME

KR20260067314AKR 20260067314 AKR20260067314 AKR 20260067314AKR-20260067314-A

Abstract

The present disclosure comprises: a first mirror including a first hole that transmits incident laser light; a second mirror that reflects laser light incident through the first hole; a third mirror that reflects laser light incident through the second mirror; a fourth mirror that reflects laser light incident through the third mirror; and a nonlinear crystal that expands the spectrum of laser light traveling back and forth through the first mirror, the second mirror, the third mirror, and the fourth mirror, wherein the first mirror, the second mirror, the third mirror, and the fourth mirror are arranged facing each other with the nonlinear crystal in between, and the first mirror, the second mirror, the third mirror, and the fourth mirror each include a plurality of first points, a plurality of second points, a plurality of third points, and a plurality of fourth points for reflection of a plurality of laser light between them in a predetermined order, and the second mirror may include a second hole that transmits the laser light finally reflected through the first mirror to the outside.

Inventors

김형우
서홍석
송동훈
김수연

Assignees

주식회사 블루타일랩

Dates

Publication Date: 20260512
Application Date: 20251016
Priority Date: 20241105

Claims (10)

A first mirror including a first hole that transmits incident laser light; A second mirror that reflects laser light incident through the first hole; A third mirror that reflects laser light incident through the second mirror; A fourth mirror that reflects laser light incident through the third mirror; and A nonlinear crystal that expands the spectrum of laser light traveling back and forth through the first mirror, the second mirror, the third mirror, and the fourth mirror, wherein The first mirror, the second mirror, the third mirror, and the fourth mirror are arranged facing each other with the non-linear crystal in between, and The first mirror, the second mirror, the third mirror, and the fourth mirror each include a plurality of first points, a plurality of second points, a plurality of third points, and a plurality of fourth points for reflection of a plurality of laser lights between them in a predetermined order. An ultrashort pulse width compression device for spectrum expansion, wherein the second mirror includes a second hole that transmits the laser light finally reflected through the first mirror to the outside.
In paragraph 1, The above plurality of first points are, Three equally spaced mirrors are formed to reflect a plurality of laser lights incident through the fourth mirror to the second mirror, and The above plurality of second points are, Three mirrors are formed at equal intervals to reflect a plurality of laser lights incident through the first mirror to the third mirror, and The above plurality of third points are, Three mirrors are formed at equal intervals to reflect a plurality of laser lights incident through the second mirror to the fourth mirror, and The above plurality of fourth points are, An ultrashort pulse width compression device for spectrum expansion, characterized by being formed at three equal intervals to reflect a plurality of laser lights incident through the third mirror to the first mirror.
A first mirror including a first hole that transmits incident laser light; A second mirror that reflects laser light incident through the first hole; A third mirror that reflects laser light incident through the second mirror; A fourth mirror that reflects laser light incident through the third mirror; and A nonlinear crystal that expands the spectrum of laser light traveling back and forth through the first mirror, the second mirror, the third mirror, and the fourth mirror, wherein The first mirror, the second mirror, the third mirror, and the fourth mirror are arranged facing each other with the non-linear crystal in between, and The first mirror, the second mirror, the third mirror, and the fourth mirror each include a plurality of first points, a plurality of second points, a plurality of third points, and a plurality of fourth points for reflection of a plurality of laser lights between them in a predetermined order. The above-mentioned fourth mirror includes a second hole that transmits the laser light finally reflected through the third mirror to the outside, an ultrashort pulse width compression device according to spectrum expansion.
In paragraph 3, The above plurality of first points are, Two mirrors are formed at equal intervals to reflect a plurality of laser lights incident through the fourth mirror to the second mirror, and The above plurality of second points are, Three mirrors are formed at equal intervals to reflect a plurality of laser lights incident through the first mirror to the third mirror, and The above plurality of third points are, Three mirrors are formed at equal intervals to reflect a plurality of laser lights incident through the second mirror to the fourth mirror, and The above plurality of fourth points are, An ultrashort pulse width compression device for spectrum expansion, characterized by having two equally spaced mirrors formed to reflect a plurality of laser lights incident through the third mirror to the first mirror.
In paragraph 2 or 4, The above laser light is, An ultrashort pulse width compression device for spectrum expansion, characterized by forming a round-trip path in sequence, one by one, through the plurality of first points, the plurality of second points, the plurality of third points, and the plurality of fourth points.
In paragraph 1 or 3, A first lens provided in alignment with the first mirror and the fourth mirror and focusing the laser light; and An ultrashort pulse width compression device for spectrum expansion, further comprising a second lens provided in alignment with the second mirror and the third mirror and focusing the laser light.
In paragraph 6, An ultrashort pulse width compression device for spectrum expansion, characterized in that the focusing intensity in the nonlinear crystal is determined according to the focal length of the lens.
In Paragraph 7, The above nonlinear crystal is, A spectral expansion ultrashort pulse width compression device characterized by having a plurality of lenses arranged between the first lens and the second lens to adjust the magnification ratio of the spectrum.
In paragraph 1 or 3, The above nonlinear crystal is, An ultrashort pulse width compression device for spectral expansion comprising any one of SF10, SF11, Fused silica, BK7, CaF2, Sapphire glass, and Birefringent crystal corresponding to the glass series.
A femtosecond fiber laser system comprising an ultrashort pulse width compression device according to spectrum expansion as described in any one of claims 1 to 9.

Description

Ultra-short pulse width compression device based on spectrum expansion, femtosecond fiber laser system including the same The present disclosure relates to a laser system. More specifically, the present disclosure relates to an ultrashort pulse width compression device for spectrum expansion and a femtosecond fiber laser system including the same. Generally, femtosecond laser light has been used in industrial settings to reduce cutting defects in semiconductor wafers and secondary battery electrodes. Here, the femtosecond laser light was modulated by a pulse control signal not only for repetition rate control but also by laser light formed from a pulse train of the femtosecond laser. At this time, laser light could be generated by a femtosecond fiber laser system. However, conventional femtosecond fiber laser systems had limitations in increasing beam intensity by adjusting the magnification ratio of the laser light spectrum and increasing the focusing intensity. Therefore, recently, there is a demand for the development of improved technology capable of increasing beam intensity by adjusting the magnification ratio of the laser light spectrum and increasing the focusing intensity. FIG. 1 illustrates a femtosecond fiber laser system according to the present disclosure. Figure 2 illustrates a detailed configuration of the femtosecond fiber laser system of Figure 1 as an example. FIG. 3 shows the wavelength of the pulsed laser light of FIG. 2, the wavelength of the first continuous wave laser light, and the wavelength of the second continuous wave laser light. Figure 4 illustrates the configuration of the ultrashort pulse width compression device of Figure 2 as an example. Figure 5 illustrates the configuration of the ultrashort pulse width compression device of Figure 2 as another example. Throughout this disclosure, the same reference numerals denote the same components. This disclosure does not describe all elements of the embodiments, and general content in the art to which this disclosure pertains or content that overlaps between embodiments is omitted. The terms ‘part, module, component, block’ as used in the specification may be implemented in software or hardware, and depending on the embodiments, a plurality of ‘parts, modules, components, blocks’ may be implemented as a single component, or a single ‘part, module, component, block’ may include a plurality of components. Throughout the specification, when a part is described as being "connected" to another part, this includes not only cases where they are directly connected but also cases where they are indirectly connected, and indirect connections include connections made via a wireless communication network. Furthermore, when it is stated that a part "includes" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components. Throughout the specification, when it is stated that a component is located "on" another component, this includes not only cases where a component is in contact with another component, but also cases where another component exists between the two components. Terms such as "first," "second," etc., are used to distinguish one component from another, and the components are not limited by the aforementioned terms. Singular expressions include plural expressions unless there is an obvious exception in the context. In each step, identification codes are used for convenience of explanation and do not describe the order of the steps; the steps may be performed differently from the specified order unless a specific order is clearly indicated in the context. The operating principles and embodiments of the present disclosure will be described below with reference to the attached drawings. FIG. 1 illustrates a femtosecond fiber laser system according to the present disclosure. FIG. 2 illustrates a detailed configuration of the femtosecond fiber laser system of FIG. 1 as an example. FIG. 3 shows the wavelength of the pulsed laser light of FIG. 2, the wavelength of the first continuous wave laser light, and the wavelength of the second continuous wave laser light. Referring to FIGS. 1 to 3, a femtosecond fiber laser system (100) according to the present disclosure may include a femtosecond light source (10), a preamplifier (20), a pulse picker (30), a first continuous wave light source (40), a main amplifier (50), an ultrashort pulse width compression device (60), a polarizing plate (65), a control module (70), and a second continuous wave light source (80). The femtosecond light source (10) can generate femtosecond laser light (12). Here, the femtosecond laser light (12) can have a frequency of about 10 MHz to about 1000 MHz. A preamplifier (20) can be connected to a femtosecond light source (10). Here, the preamplifier (20) can amplify femtosecond laser light (12). The pulse speaker (30) can be connected to a preamplifier (20). Here, the pulse speaker (