CN104475982A - Iron coloring based femtosecond laser glass machining method - Google Patents

Abstract

The invention relates to a method for processing glass with a femtosecond laser based on ion coloring, and belongs to the field of laser applications. The method includes: 1) doping transition metal ions or rare earth ions into the glass to be processed, and the concentration of the ion doping reaches to change the absorption spectrum of the glass to be processed and form an absorption peak to obtain colored glass; 2) measure the first ) the absorption spectrum of the color glass obtained in the first step, and the wavelength of the absorption peak in the absorption spectrum is used as the resonant absorption wavelength; 3) the surface or inside of the color glass is processed by a femtosecond laser process, wherein the femtosecond laser used The wavelength is equal to the resonant absorption wavelength. Compared with the traditional femtosecond laser processing method, the method of the invention can realize high-efficiency and wavelength-selective processing of materials.

Description

A Femtosecond Laser Glass Processing Method Based on Ion Coloring

technical field

The invention relates to the field of laser applications, in particular to a method for processing glass with a femtosecond laser based on ion coloring.

Background technique

In the field of micro-nano manufacturing, femtosecond laser has very high energy density and ultra-short pulse width, can completely ionize almost all materials, and is very suitable for processing transparent glass materials. However, due to the limitation of photon absorption efficiency, femtosecond laser processing efficiency is very low, which is not suitable for industrial applications. Resonance absorption can effectively improve the absorption efficiency of photons. When the laser photon energy hν is equal to the electronic transition energy level difference of the processed material, the resonance absorption effect will occur, and the absorption efficiency of the material to the laser will increase several times. In the literature H.P.Liu, S.H.Yin, J.Y.Zhang, L.Wang, B.Jiang, and N.Q.Lou: Phys.Rev.A 74,053418 (2006), the authors realized the resonance-enhanced multiple Photon ionization, the ammonia molecule absorbs two 265nm photons at the same time, after resonant transition from the lower state to the intermediate state, and then absorbs a 401nm photon to generate ionization. However, for a wide bandgap material such as glass, there is no intermediate energy level that can be adjusted within the tuning range of the laser wavelength to achieve resonant absorption of photons.

Contents of the invention

The purpose of the present invention is to solve the problem of low processing efficiency when the femtosecond laser technology processes glass materials, and to provide a method for processing glass based on ion coloring femtosecond laser.

The purpose of the present invention is to realize through the following technical solutions:

A kind of method of femtosecond laser processing glass based on ion coloring of the present invention, described method comprises the following steps:

1) Doping transition metal ions or rare earth ions into the glass to be processed, the concentration of ion doping reaches to change the absorption spectrum of the glass to be processed and form an absorption peak to obtain colored glass;

2) measure the absorption spectrum of the colored glass obtained in step 1), and use the wavelength of the absorption peak in the absorption spectrum as the resonance absorption wavelength;

3) Process the surface or interior of the colored glass by using femtosecond laser technology, wherein the wavelength of the femtosecond laser used is equal to the resonant absorption wavelength.

Among the processing methods, the ion doping method in step 1) is preferably a high-temperature melting method.

In the processing method, the method of measuring the absorption spectrum of the colored glass in step 2) adopts an ultraviolet-visible-near-infrared spectrometer to measure at room temperature.

The beneficial effect of the present invention is that: the present invention selectively adds intermediate energy levels in the energy band structure by doping transition metal ions or rare earth ions into the glass, thereby changing the optical absorption characteristics and corresponding colors of the material, making it suitable for Specific energy photons produce resonant absorption. Compared with traditional femtosecond laser processing methods, it can realize high-efficiency and wavelength-selective processing of materials.

Description of drawings

Fig. 1 is the absorption spectrum of the doped glass and the undoped glass described in the embodiment of the present invention, and the electronic transition energy levels corresponding to the absorption peaks.

Detailed ways

The content of the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

The femtosecond laser used in all the examples is produced by American Spectrum Physics Corporation. The laser wavelength is 800nm, the pulse width is 50fs, the repetition frequency is 1kHZ, the maximum energy of a single pulse is 3mJ, the light intensity distribution is Gaussian, and linearly polarized. The optical parametric amplifier used in all examples is TOPAS-C produced by Lithuania LightConvertion Company, which can make the laser pulse with a wavelength of 800nm continuously adjustable in the wavelength range of 290-2600nm;

Example 1:

Taking the femtosecond laser processing glass method based on ion coloring of the present invention, doping Co ²⁺ ions into the glass and drilling holes on the material surface as an example,

The specific processing steps are as follows:

(1) Incorporate the transition metal ion Co ²⁺ into the glass. In this embodiment, the high-temperature melting method is used to dope metal ions into the glass matrix in the form of oxide CoO, and the doping concentration is 3.0 mass%. The composition of the glass matrix is 70SiO ₂ -20Na ₂ O-10CaO (mass%), which belongs to silicate glass;

(2) Use a UV-Vis-NIR spectrometer to measure the absorption spectrum of Co ²⁺ doped glass at room temperature, as shown in Figure 1. Co ²⁺ doped glass has an absorption peak at a wavelength of 600nm, which is the resonant absorption wavelength, and the corresponding electronic transition energy level of Co ²⁺ is ⁴ A ₂ to ⁴ T ₁ ;

(3) Use an optical parametric amplifier to adjust, so that the output wavelength of the femtosecond laser is 600 nm.

(4) Fix the material on the mobile platform, and focus the laser on the surface of the material for processing. When the number of incident laser pulses is 50, the ablation threshold of the material is 1.47J/cm ² ; when the pulse energy density is 3.78J/cm ² , the ablation depth is 0.79μm.

Example 2:

Taking the traditional femtosecond laser processing method to drill holes on the surface of undoped glass as an example, the specific processing steps are as follows:

Other steps are the same as in Example 1, except that the doping process in steps (1) and (2) is not performed, and the sample used is undoped glass, and the composition of the glass is 70SiO ₂ -20Na ₂ O-10CaO (mass%), belongs to silicate glass. When the number of incident laser pulses is 50, the ablation threshold of the material is 2.33J/cm ² ; when the pulse energy density is 3.78J/cm ² , the ablation depth is 0.43μm.

Example 3:

Taking the method of processing glass based on ion-colored femtosecond laser of the present invention, doping Cu ²⁺ ions in the glass and punching holes on the material surface as an example, the specific processing steps are as follows:

(1) Incorporate transition metal ions Cu ²⁺ into the glass. In this embodiment, a high-temperature melting method is used to dope metal ions into the glass matrix in the form of CuO oxide, and the doping concentration is 2.0 mass%. The composition of the glass matrix is 70SiO ₂ -20Na ₂ O-10CaO (mass%), which belongs to silicate glass;

(2) Measure the absorption spectrum of the Cu ²⁺ doped glass at room temperature using an ultraviolet-visible-near-infrared spectrometer, as shown in Figure 1. Cu ²⁺ doped glass has an absorption peak at a wavelength of 800nm, which is the resonant absorption wavelength, and the corresponding electronic transition energy level of Cu ²⁺ is ² E to ² T ₂ ;

(3) Use an optical parametric amplifier to adjust the femtosecond laser wavelength to 800nm.

(4) Fix the material on the mobile platform, and focus the laser on the surface of the material for processing. When the number of incident laser pulses is 50, the ablation threshold of the material is 2.13J/cm ² ; when the pulse energy density is 3.78J/cm ² , the ablation depth is 0.51μm.

Example 4:

Taking the traditional femtosecond laser processing method to drill holes on the surface of undoped glass as an example, the specific processing steps are as follows:

Other steps are the same as in Example 3, except that the doping process in steps (1) and (2) is not performed, the sample used is undoped glass, and the composition of the glass is 70SiO ₂ -20Na ₂ O-10CaO (mass%), belongs to silicate glass. When the number of incident laser pulses is 50, the ablation threshold of the material is 2.98J/cm ² ; when the pulse energy density is 3.78J/cm ² , the ablation depth is 0.22μm.

By embodiment 1-4 compare as seen:

(1) After doping Co ²⁺ ions into the glass, at the resonant absorption wavelength of 600nm, the ablation threshold of the material decreased by 36.8%, and the ablation depth increased by 81.5%.

(2) After doping Cu ²⁺ ions into the glass, at the resonant absorption wavelength of 800nm, the ablation threshold of the material decreased by 28.4%, and the ablation depth increased by 128.9%.

(3) The ablation threshold of the material decreases as the ion doping concentration increases, resulting in higher processing efficiency.

The present invention is not limited to the above-mentioned best implementation mode, anyone can draw other various forms of products under the enlightenment of the present invention, but no matter it makes any changes in shape or structure, all those with the same or similar features as the present application Approximate technical solutions all fall within the protection scope of the present invention.

Claims (3)

1., based on a method for the femtosecond laser processed glass of ion coloring, it is characterized in that: said method comprising the steps of:

1) mix in glass to be processed by transition metal ions or rare earth ion, the concentration of ion doping reaches and makes the absorption spectrum of glass to be processed change and form absworption peak, obtains coloured glass;

2) the 1st is measured) absorption spectrum of coloured glass that obtains of step, using the wavelength of absworption peak in this absorption spectrum as resonant absorption wavelengths;

3) adopt femtosecond laser technique to process the surface of described coloured glass or inside, the wavelength of the femtosecond laser wherein adopted equals resonant absorption wavelengths.

2. the method for the femtosecond laser processed glass based on ion coloring according to claim 1, is characterized in that: in described processing method, the 1st) the ion method of mixing of step is high-temperature melting method.

3. the method for the femtosecond laser processed glass based on ion coloring according to claim 1, it is characterized in that: in described processing method, the 2nd) absorption spectrum method of the middle measurement coloured glass of step adopts ultraviolet-visible-near-infrared spectrum instrument at room temperature to measure.