CN221040527U - Optical device and femtosecond laser direct writing system - Google Patents

Abstract

The utility model discloses an optical device and a femtosecond laser direct writing system, wherein the optical device comprises: a light source unit for emitting laser light, a spatial light modulator, a phase diagram, and a stage; the phase map is loaded to the spatial light modulator, and the spatial light modulator and the phase map act on incident laser and modulate the laser into a multi-focus light field; and the objective table is used for bearing a sample, and the multi-focus light field is written into the sample. The laser is emitted by the light source part, the laser is modulated into a multi-focus light field by the spatial light modulator and the phase diagram, and the multi-focus light field processes a sample arranged on the object stage, so that information writing is realized. The optical device can synchronously write a plurality of point location information by modulating single laser into a large-scale multi-focus light field, so that the writing efficiency of a sample can be greatly improved, and the practicability of the optical device can be improved.

Description

Optical device and femtosecond laser direct writing system

Technical Field

The utility model relates to the field of optical information reading, in particular to an optical device and a femtosecond laser direct writing system.

Background

Information storage is an important component of human development. In the process that the human is going to civilization, information is continuously accumulated and transmitted instead of being transmitted, and the history and civilization of the human are formed. Particularly, after the 21 st century, digital information technology is rapidly advanced, and artificial intelligence, big data, the Internet of things and the like synchronously generate explosive mass data while promoting economic and social development progress.

Massive amounts of data require a large amount of storage space, and optical storage technology is an important storage technology. The five-dimensional optical storage is based on fused quartz material, the fused quartz is used as a quartz sample, and femtosecond laser is utilized to induce the physical structure change of the nano grating in the quartz sample, so that information storage is realized.

At present, when a quartz sample is written by using a femtosecond laser, the problem of low writing speed exists, and the requirement of high-speed information storage is difficult to meet.

Disclosure of utility model

The utility model aims to overcome the defect of slower speed when a sample is written by using femtosecond laser in the prior art, and provides an optical device and a femtosecond laser direct writing system.

The utility model solves the technical problems by the following technical scheme:

An optical device, the optical device comprising: a light source unit for emitting laser light, a spatial light modulator, a phase diagram, and a stage; the phase map is loaded to the spatial light modulator, and the spatial light modulator and the phase map act on incident laser and modulate the laser into a multi-focus light field; the stage is for carrying a sample, the multifocal light field being written to the sample.

In this scheme, through adopting above-mentioned structure, utilize light source portion to send laser, spatial light modulator and phase diagram modulate laser into the multifocal light field, multifocal light field processes the sample that locates the objective table, realizes the write-in of information. The optical device can synchronously write a plurality of point location information by modulating single laser into a large-scale multi-focus light field, so that the writing efficiency of a sample can be greatly improved, and the practicability of the optical device can be improved.

As an embodiment, the phase map is converted into a computer generated hologram based on the spatial light modulator, the hologram comprising the intensity and phase information of the laser light, the phase distribution ranging from 0-2 pi.

In the scheme, by adopting the structure, the phase diagram is converted into the hologram generated by the computer by using the spatial light modulator, the phase diagram contains large-scale multifocal modulation phase information and phase information of the interference crosstalk suppression filter, interference crosstalk of a multifocal light field can be reduced, resolution of the large-scale multifocal light field is improved, and high intensity uniformity of a large-scale focal array is ensured.

As one embodiment, the optical device further includes a primary polarization conversion lens group disposed downstream of the light source section, into which the laser light is incident, the primary polarization conversion lens group being for normalizing a polarization state of the laser light;

and/or the optical device further comprises a beam expander group, wherein the beam expander group is arranged at the downstream of the light source part, laser is injected into the beam expander group, and the beam expander group is used for expanding the spot diameter of the laser to 3-8 times of the original spot diameter.

In this scheme, through adopting above structure, utilize one-level polarization conversion lens group to normalize the polarization state of laser, can improve the homogeneity of laser.

The beam expander group is utilized to improve the diameter of a laser spot, laser with larger diameter is injected into the spatial light modulator, interference crosstalk of a multi-focus light field is reduced conveniently, and the resolution of the multi-focus light field can be improved.

As one embodiment, the optical device further includes a first mirror disposed on a laser path between the primary polarization conversion lens group and the beam expander lens group, the first mirror being configured to receive the laser light emitted from the primary polarization conversion lens group, and the first mirror being further configured to reflect the laser light to the beam expander lens group.

In this scheme, through adopting above structure, utilize the route of first speculum adjustment laser for one-level polarization conversion lens group and beam expanding lens group can set up in different directions, and each subassembly of more compact arrangement of being convenient for can avoid optical device size too big in a certain direction.

As one embodiment, the optical device further comprises a secondary polarization conversion lens group, the multi-focus light field is incident on the secondary polarization conversion lens group, and the secondary polarization conversion lens group is used for modulating the multi-focus light field into a vector polarized light field;

and/or the optical device further comprises a high-frequency filter lens group, wherein the multi-focus light field is incident into the high-frequency filter lens group, and the high-frequency filter lens group is used for condensing and/or filtering the multi-focus light field.

In the scheme, by adopting the structure and utilizing the two-stage polarization conversion lens group to modulate the multi-focus light field into the vector polarized light field, interference crosstalk of the multi-focus light field can be reduced, and resolution of the multi-focus light field can be improved.

The high-frequency filter lens group can filter scattered light waves, and can reduce the diameter of a multi-focus light field, so that the sample processing is facilitated.

As one embodiment, the optical device further comprises an objective lens disposed above the stage, the multi-focal light field being directed through the objective lens to the sample.

In the scheme, by adopting the structure, the object lens is utilized to focus the multi-focus light field, so that the multi-focus light field is convenient to write into a sample, and the information density can be improved.

As one embodiment, the optical device further comprises a monitoring component for observing the process of writing to the sample.

In this scheme, through adopting above structure, utilize the monitoring component to observe the process of writing in the sample, can learn the writing state in real time.

As one embodiment, the monitoring assembly includes a sensor for detecting light reflected from the sample and converting the light into an electrical signal;

and/or the monitoring assembly further comprises a variable focus imaging lens assembly for receiving light reflected from the sample and focusing the light;

And/or the monitoring assembly further comprises a dichroic mirror for receiving the multifocal light field and reflecting the multifocal light field to the sample; the dichroic mirror is also used to transmit light reflected from the sample.

In this scheme, through adopting above structure, utilize the inductor to convert light into the signal of telecommunication, be convenient for utilize the computer to show the course of working.

The zoom imaging lens component is convenient for focusing, and can adjust the monitoring area in time.

The dichroic mirror simultaneously realizes the reflection of the multi-focus light field and the transmission of the reflected light rays of the sample, is convenient for compactly arranging various components, and can avoid oversized optical devices in a certain direction.

As one embodiment, the optical device further comprises a light supplementing light source and a second reflecting mirror, wherein the second reflecting mirror is used for reflecting the light rays emitted by the light supplementing light source to the sample.

In this scheme, through adopting above structure, utilize the light filling light source can improve sample luminance. The second reflector enables the light supplementing light source and the sample to be arranged in different directions, so that each component can be arranged more compactly, and oversized optical device in a certain direction can be avoided.

A femtosecond laser direct write system comprising the optical device of any one of the above.

In this scheme, through adopting above structure, the system is write through to the femtosecond laser includes above optical device, can realize writing in of extensive point location information in step, can very big improvement sample write-in efficiency, can improve the quick write-in ability of the system is write through to the femtosecond laser.

On the basis of conforming to the common knowledge in the field, the above preferred conditions can be arbitrarily combined to obtain the preferred examples of the utility model.

The utility model has the positive progress effects that:

The utility model utilizes the light source part to emit laser, the spatial light modulator and the phase diagram to modulate the laser into a multi-focus light field, and the multi-focus light field processes the sample arranged on the object stage, thereby realizing information writing. The optical device can synchronously write a plurality of point location information by modulating single laser into a large-scale multi-focus light field, so that the writing efficiency of a sample can be greatly improved, and the practicability of the optical device can be improved.

Drawings

Fig. 1 is a schematic view of an optical path of an optical device according to an embodiment of the utility model.

Fig. 2 is a schematic diagram of a phase diagram in an embodiment of the utility model.

FIG. 3 is a schematic view of an optical path of another optical device according to an embodiment of the utility model.

FIG. 4 is a diagram of a pattern of multi-focal light fields of a femtosecond laser direct-write system directed to a sample according to an embodiment of the utility model.

Reference numerals illustrate:

Optical device 100

Light source 11

Spatial light modulator 12

Phase diagram 13

Stage 14

First order polarization conversion lens group 15

Beam expander group 16

First reflecting mirror 17

Second-order polarization conversion lens group 18

High-frequency filter lens group 19

Objective lens 20

Monitoring assembly 30

Inductor 31

Zoom imaging lens assembly 32

Dichroic mirror 33

Light source 34 for supplementing light

Second mirror 35

Sample 90

Laser 91

Detailed Description

The present utility model will be more fully described by way of examples below with reference to the accompanying drawings, which, however, are not intended to limit the utility model to the scope of the examples.

As shown in fig. 1 to 3, the present embodiment includes an optical device 100 and a femtosecond laser direct writing system. Wherein the femtosecond laser direct writing system comprises an optical device 100.

Referring to fig. 1, an optical device 100 includes: a light source unit 11, a spatial light modulator 12, a phase diagram 13, and a stage 14, the light source unit 11 being configured to emit laser light 91; the phase map 13 is loaded to the spatial light modulator 12, and the spatial light modulator 12 and the phase map 13 are used for receiving the laser light 91 and modulating the laser light 91 into a multi-focus light field; stage 14 is used to carry a sample 90, and a multi-focal light field is written into sample 90. The laser beam 91 is emitted from the light source 11, and the spatial light modulator 12 and the phase map 13 modulate the laser beam 91 into a multi-focal optical field, which processes the sample 90 provided on the stage 14, thereby writing information. By modulating the single laser beam 91 into a multi-focal optical field, the optical device 100 can write information of a plurality of spots simultaneously, and can greatly improve the writing efficiency of the sample 90 and the practicality of the optical device 100.

The light source 11 emits laser light, and the spatial light modulator 12 and the phase map 13 act on the incident laser light, and the spatial light modulator 12 and the phase map 13 modulate the laser light into a multifocal light field. The multi-focal optical field processes the sample 90 provided on the stage 14, and the rapid writing of the femtosecond laser is realized by increasing the writing amount by the multi-focal optical field at the maximum writing speed that is currently available. The optical device 100 can synchronously write large-scale point location information by modulating a single laser beam into a multi-focus optical field, can greatly improve the writing efficiency of a sample, and can improve the quick writing capability of an optical system.

A large-scale multifocal light field is understood to be a light field with a number of foci exceeding 300. As shown in fig. 4, the pattern of the multi-focal light field of the femtosecond laser direct writing system of the embodiment impinging on the sample 90 is shown, and the number of focal points is 400.

As an example, the light source section 11 may include a member capable of generating and emitting the laser light 91, and the wavelength range of the laser light 91 may include 515nm, 532nm, 800nm, 1030nm, and the like. The light source section 11 can be understood as a femtosecond laser 91.

Stage 14 may include a nano-displacement stage, stage 14 may implement displacement in multiple dimensions, and precision control of the displacement may be on the nano-scale.

The material of the sample 90 may include transparent materials such as glass, plastic, quartz, etc. The optical device 100 may write information directly within the sample 90.

The spatial light modulator 12 may implement modulation of the phase of the laser light 91. The spatial light modulator 12, in conjunction with the phase map 13, can modulate a single laser beam 91 into a multi-focal light field. A multifocal light field may be understood to comprise a plurality of laser 91 beams.

Referring to fig. 2, there is shown a phase diagram 13 of a light field capable of producing 400 lattice light with a phase distribution of 0-2 pi. In the figure, the darker the color, the closer the phase angle is to-pi, the lighter the color, and the closer the phase is to pi. In other examples, the phase map 13 may also include other numbers of lattices, and the number of lattices of the phase map 13 may range from 300 points to 500 points.

The implementation of a multifocal light field relies mainly on the phase map 13 in fig. 2, which phase map 13 is loaded into the spatial light modulator 12, converted into a CGH hologram (Computer-GENERATED HOLOGRAMS, computer-generated hologram) by the system of spatial light modulator 12. The unique property of the hologram is that it can record both the intensity and phase of information, and the hologram is loaded into the liquid crystal reflective panel of the spatial light modulator 12, thereby effecting phase modulation of the incident light beam. The 400 lattice light field phase map 13 can integrate the small-hole filter modulation and the multi-focus phase modulation of a single focus in the design process, can effectively reduce interference crosstalk in the multi-focus light field, and reduces the electric field intensity of the maximum diffraction sidelobe of the single focus, thereby improving the resolution of the multi-focus light field and the uniformity of the light field, and obtaining a small-spacing multi-focus light field array so as to realize high-resolution processing application. Compared with a phase pre-compensation method, the design and regulation of the multi-focus light field filter are more flexible, the spatial resolution of the multi-focus light field can be flexibly regulated and controlled by the small-hole filter, and the structure and the number of focuses of the multi-focus light field can be flexibly regulated and controlled according to the difference of the structures and the number of focuses of the multi-focus light field.

As an embodiment, the spatial light modulator 12 converts the phase map 13 into a computer generated hologram comprising the intensity and phase of the laser light 91 with a phase distribution in the range of 0-2 pi. The spatial light modulator 12 is used for converting the phase map 13 into a computer-generated hologram, the phase distribution range of the hologram is large, interference crosstalk of a multi-focus light field can be reduced, and resolution and illumination intensity uniformity of the multi-focus light field can be improved.

Referring to fig. 3, the optical apparatus 100 further includes a primary polarization conversion lens group 15, the primary polarization conversion lens group 15 is disposed downstream of the light source portion 11, the laser light 91 is incident on the primary polarization conversion lens group 15, and the primary polarization conversion lens group 15 is used for normalizing the polarization state of the laser light 91; the uniformity of the laser light 91 can be improved by normalizing the polarization state of the laser light 91 with the primary polarization conversion lens group 15. The primary polarization conversion lens group 15 may specifically include a half-wave plate and a graticule prism, and in other examples, the primary polarization conversion lens group 15 may also include other polarization converters.

The optical device 100 further includes a beam expander group 16, the beam expander group 16 is disposed downstream of the light source 11, the laser beam 91 is incident on the beam expander group 16, and the beam expander group 16 is configured to expand the spot diameter of the laser beam 91 to 3-10 times the original spot diameter. The beam expander group 16 is utilized to improve the diameter of the light spot of the laser 91, and the laser 91 with larger diameter is injected into the spatial light modulator 12, so that interference crosstalk of a multi-focus light field is reduced, and the resolution of the multi-focus light field can be improved. The diameter of the laser beam 91 emitted from the light source 11 is usually 1 to 3 μm, and the beam expander group 16 can adjust the diameter of the laser beam 91 to 9 to 10 μm. The adjusted laser light 91 can be irradiated to the liquid crystal reflection panel of the spatial light modulator 12 in a wider range.

The optical device 100 further includes a first reflecting mirror 17, where the first reflecting mirror 17 is disposed on the laser beam 91 path between the primary polarization conversion lens group 15 and the beam expander lens group 16, the first reflecting mirror 17 is configured to receive the laser beam 91 emitted from the primary polarization conversion lens group 15, and the first reflecting mirror 17 is further configured to reflect the laser beam 91 to the beam expander lens group 16. The first reflecting mirror 17 is used for adjusting the path of the laser beam 91, so that the first polarization conversion lens group 15 and the beam expanding lens group 16 can be arranged in different directions, each component is convenient to be arranged more compactly, and the optical device 100 can be prevented from being oversized in a certain direction.

The optical device 100 further includes a second polarization conversion lens group 18, the multi-focal light field enters the second polarization conversion lens group 18, and the second polarization conversion lens group 18 is used for modulating the multi-focal light field into a vector polarized light field; the use of the secondary polarization conversion lens group 18 to modulate the multi-focal light field into a vector polarized light field can reduce interference crosstalk of the multi-focal light field and can also improve resolution of the multi-focal light field. The secondary polarization conversion lens group 18 may include a half slide and a spiral slide, and in other examples, the secondary polarization conversion lens group 18 may be other devices.

The optical device 100 further comprises a high frequency filter lens group 19, the multi-focal light field being incident on the high frequency filter lens group 19, the high frequency filter lens group 19 being used for beam shrinking and/or filtering the multi-focal light field. The high-frequency filter lens group 19 can filter scattered light waves, and can also reduce the diameter of a multi-focus light field, so that the sample 90 can be processed conveniently.

The optical device 100 further includes an objective lens 20, the objective lens 20 being disposed above the stage 14, the multi-focal light field being directed through the objective lens 20 to the sample 90. Focusing the multi-focal light field with the objective lens 20 facilitates writing the multi-focal light field into the sample 90, which can increase the information density. The objective lens 20 may specifically comprise a high numerical aperture objective lens 20.

The optical device 100 further comprises a monitoring assembly 30, the monitoring assembly 30 being adapted to observe the writing of the sample 90. The writing state can be known in real time by observing the process of writing the sample 90 with the monitoring assembly 30.

The monitoring assembly 30 includes a sensor 31, the sensor 31 being configured to detect light reflected from the sample 90 and convert the light into an electrical signal; the light is converted into an electrical signal by the sensor 31, so that the processing procedure is displayed by a computer.

The monitoring assembly 30 may also include a memory for storing parameter data and a calculation program for calculating parameters of the sample from the loss parameter data;

the monitoring component 30 may also include a processor for executing the computing program.

The monitoring assembly 30 may also include a display for displaying the above-described calculation process and calculation results.

The monitoring assembly 30 further includes a variable focus imaging lens assembly 32, the variable focus imaging lens assembly 32 for receiving light reflected from the sample 90 and focusing the light; the variable focus imaging lens assembly 32 facilitates focusing and allows for timely adjustment of the monitored area.

The monitoring assembly 30 further comprises a dichroic mirror 33, the dichroic mirror 33 for receiving the multi-focal light field and reflecting the multi-focal light field to the sample 90; the dichroic mirror 33 is also used to transmit light reflected from the sample 90. The dichroic mirror 33 simultaneously effects reflection of the multi-focal light field and transmission of reflected light from the sample 90, facilitating a more compact arrangement of the components, avoiding oversized optics 100 in one direction.

The optical device 100 further includes a light-compensating light source 34 and a second reflecting mirror 35, where the second reflecting mirror 35 is used for reflecting the light emitted by the light-compensating light source 34 to the sample 90. The brightness of the sample 90 can be increased using the light-compensating light source 34. The second reflector 35 allows the light supplementing light source 34 and the sample 90 to be disposed in different directions, which facilitates more compact arrangement of the components and avoids oversized optical device 100 in a certain direction. The light supplementing light source 34 may specifically include an LED light source, a fluorescent lamp, an incandescent lamp, and the like.

The first mirror 17, the second mirror 35 may include a dielectric film mirror, a half mirror, or the like.

In fig. 3, the memory, processor and display of the optical device 100 may be integrated as a computer. The sensor 31 is in communication with a computer which receives and processes the parameter data obtained by the sensor 31 and calculates the corresponding information. The computer is also in communication connection with a controller, which can specifically adjust the position of the carrying part.

The present example also includes a femtosecond laser direct-write system including any one of the optical devices 100 described above. The femtosecond laser direct writing system includes the optical device 100 as described above, so that writing of a plurality of point location information can be synchronously realized, the writing efficiency of the sample 90 can be greatly improved, and the practicability of the femtosecond laser direct writing system can be improved.

As understood in connection with fig. 3, the femtosecond laser direct writing system may include 515nm femtosecond laser 91, a first polarization conversion lens group 15, a first reflecting mirror 17, a beam expander group 16, a spatial light modulator 12, a second polarization conversion lens group 18, a high-frequency filter lens group 19, a dichroic mirror 33, a second reflecting mirror 35, a light supplementing light source 34, a high numerical aperture objective lens 20, a nano-displacement stage, a zoom imaging lens group, a CCD, and the like. First, 515nm of femtosecond laser 91 is emitted by a femtosecond laser 91, enters a first-stage polarization conversion lens group 15 to normalize polarization states, then enters a beam expanding lens group 16 through a first reflecting mirror 17, and the beam after beam expansion enters a spatial light modulator 12 to carry out phase modulation of an optical field. The light beam modulated by the spatial light modulator 12 enters the secondary polarization conversion lens group 18 to convert the horizontal linear polarized light field into a multi-focus vector polarized light field, the multi-focus vector light field is condensed and filtered by the high-frequency filter lens group 19, reflected by the dichroic mirror 33 and enters the high-numerical aperture objective lens 20 to be focused into sample fused quartz, and the sample fused Dan Yinggu is fixed in a nano displacement table to realize multi-focus direct writing processing by the relative motion of the displacement table. The illumination of the whole femtosecond laser direct writing system is realized by a second reflecting mirror 35 and an LED light source, and the imaging monitoring of the processing process is realized by a zoom imaging lens group and a CCD.

The single exposure of the femtosecond laser direct writing system can realize multi-focus light field etching with more than 300 lattice, and the speed of writing optical storage information by the femtosecond laser 91 can be greatly improved. The phase modulation mode of the femtosecond laser direct writing system is simpler and more flexible, and the regulation and control of different numbers of lattices can be realized; diffraction sidelobe intensity among focuses in the array can be effectively inhibited, and the resolution and intensity uniformity of a multi-focus light field are improved. Light fields with different polarization states can be obtained, and more space degrees of freedom are provided for the femto-second laser 91 to write the nano grating.

While specific embodiments of the utility model have been described above, it will be appreciated by those skilled in the art that this is by way of example only, and the scope of the utility model is defined by the appended claims. Various changes and modifications to these embodiments may be made by those skilled in the art without departing from the principles and spirit of the utility model, but such changes and modifications fall within the scope of the utility model.

Claims (10)

1. An optical device, the optical device comprising:

A light source section for emitting laser light;

The system comprises a spatial light modulator and a phase diagram, wherein the phase diagram is loaded to the spatial light modulator, acts on incident laser and modulates the laser into a multi-focus light field;

And the objective table is used for bearing a sample, and the multi-focus light field is written into the sample.

2. The optical device of claim 1, wherein the spatial light modulator converts the phase map into a computer-generated hologram comprising the intensity and phase of the laser light with a phase distribution in the range of 0-2 pi.

3. The optical device according to claim 1, further comprising a primary polarization conversion lens group provided downstream of the light source section, into which the laser light is incident, the primary polarization conversion lens group being for normalizing a polarization state of the laser light;

And/or the optical device further comprises a beam expander group, wherein the beam expander group is arranged at the downstream of the light source part, laser is injected into the beam expander group, and the beam expander group is used for expanding the spot diameter of the laser to 3-10 times of the original spot diameter.

4. The optical device of claim 3, further comprising a first mirror disposed in a laser path between the primary polarization conversion lens group and the beam expander lens group, the first mirror configured to receive laser light emitted from the primary polarization conversion lens group, the first mirror further configured to reflect the laser light to the beam expander lens group.

5. The optical device of claim 1, further comprising a secondary polarization conversion lens group into which the multi-focal light field impinges, the secondary polarization conversion lens group for modulating the multi-focal light field into a vector polarized light field;

and/or the optical device further comprises a high-frequency filter lens group, wherein the multi-focus light field is incident into the high-frequency filter lens group, and the high-frequency filter lens group is used for condensing and/or filtering the multi-focus light field.

6. The optical device of claim 1, further comprising an objective lens disposed above the stage, the multi-focal light field impinging on the sample through the objective lens.

7. The optical device of any one of claims 1-6, further comprising a monitoring assembly for observing a writing process to the sample.

8. The optical device of claim 7, wherein the monitoring assembly comprises a sensor for detecting light reflected from the sample and converting the light into an electrical signal;

and/or the monitoring assembly further comprises a variable focus imaging lens assembly for receiving light reflected from the sample and focusing the light;

And/or the monitoring assembly further comprises a dichroic mirror for receiving the multifocal light field and reflecting the multifocal light field to the sample; the dichroic mirror is also used to transmit light reflected from the sample.

9. The optical device of claim 7, further comprising a light supplementing light source and a second reflector for reflecting light from the light supplementing light source to the sample.

10. A femtosecond laser direct writing system comprising an optical device as claimed in any one of claims 1 to 9.