阅读说明：本技术 一种基于微流控的可调光束分束器 (Micro-fluidic-based adjustable light beam splitter ) 是由 段修栋 宋潮龙 杨韵燃 涂鑫 于 2021-07-06 设计创作，主要内容包括：本发明提供了一种基于微流控的可调光束分束器,包括：激光器、流体控制系统、Y分支波导和带CCD的倒置荧光显微镜；Y分支波导为PDMS在硅片上倒模制成的微流控芯片,且关于水平线对称,包括：芯层,位于芯层上方的包层A,位于芯层下方的包层B,位于波导末端的包层C,Y分支波导的分支点前设置一个朝向通道入口方向的楔形块,激光器输入光源通过光纤耦合到微流控芯片中,通过流体控制系统控制流体的流量大小,改变芯层流体的位置和宽度以实现动态调节分光比。本发明使用PDMS微流控芯片构建流体光波导进而得到一种基于微流控的可调光束分束器,实现了较大的分光比调节范围。制造工艺简单、实施成本低。(The invention provides a microfluidic-based adjustable beam splitter, comprising: a laser, a fluid control system, a Y-branch waveguide and an inverted fluorescence microscope with a CCD; the Y-branch waveguide is a microfluidic chip which is made by inverse molding PDMS on a silicon chip and is symmetrical about a horizontal line, and comprises: the laser input light source is coupled into the micro-fluidic chip through an optical fiber, the flow rate of the fluid is controlled through a fluid control system, and the position and the width of the fluid in the core layer are changed to realize dynamic adjustment of the splitting ratio. According to the invention, the PDMS micro-fluidic chip is used for constructing the fluid optical waveguide, so that the micro-fluidic adjustable beam splitter is obtained, and a larger splitting ratio adjusting range is realized. The manufacturing process is simple and the implementation cost is low.)

1. A microfluidic-based adjustable beam splitter, the adjustable beam splitter comprising: a laser, a fluid control system, a Y-branch waveguide and an inverted fluorescence microscope with a CCD;

the Y-branch waveguide is a microfluidic chip which is made by inverse molding PDMS on a silicon chip and is symmetrical about a horizontal line, and comprises: the laser comprises a core layer, a cladding layer A positioned above the core layer, a cladding layer B positioned below the core layer and a cladding layer C positioned at the tail end of a waveguide, wherein a wedge-shaped block facing the inlet direction of a channel is arranged in front of a branch point of the Y-branch waveguide, an input light source of the laser is coupled into a micro-fluidic chip through an optical fiber, and the position and the width of fluid in the core layer are changed to realize dynamic adjustment of the splitting ratio by controlling the flow of the fluid through the fluid control system.

2. The microfluidics-based tunable beam splitter of claim 1, wherein the Y-branch waveguide has an active area length of 1900 μm, a width of 430 μm, and a height of 125 μm.

3. The microfluidic-based tunable beam splitter of claim 1, wherein the cladding layers a, B, C are fed with ethylene glycol and the core layer is fed with cinnamaldehyde.

4. The microfluidics-based adjustable beam splitter of claim 1, wherein the tips of the wedge-shaped blocks are at an angle of 15 °, 500 μ ι η long and 130 μ ι η wide.

5. The microfluidics-based adjustable beam splitter of claim 1, wherein the Y-branch waveguide comprises a main channel and two branch channels, each branch channel making an angle of 27 ° with the main channel.

6. The microfluidics-based tunable beam splitter of claim 1, wherein the fluid control system is implemented with a dual channel syringe pump.

7. The microfluidic-based tunable beam splitter of claim 1, wherein the core layer, the cladding layer a, the cladding layer B, and the cladding layer C are all rectangular in cross-section.

Technical Field

The invention relates to the field of construction of fluid optical waveguides, in particular to an adjustable beam splitter based on microfluidics.

Background

The Y-branch waveguide plays an important role in optical systems such as optical switches, optical power splitters, mach-zehnder interferometers, and the like. However, the tunability of solid waveguides limits the beam splitting function. Optical flow control has many properties not found in solids. A novel Y-branch fluid optical waveguide device is designed based on the microfluidic technology, and small additional loss and a large light intensity ratio adjustable range are realized.

Disclosure of Invention

The invention aims to provide a microfluidic-based adjustable beam splitter, which realizes smaller additional loss and larger adjustable range of light intensity ratio.

In order to achieve the above object, the present invention provides a microfluidic-based adjustable beam splitter comprising: a laser, a fluid control system, a Y-branch waveguide and an inverted fluorescence microscope with a CCD;

the Y-branch waveguide is a microfluidic chip which is made by inverse molding PDMS on a silicon chip and is symmetrical about a horizontal line, and comprises: the laser comprises a core layer, a cladding layer A positioned above the core layer, a cladding layer B positioned below the core layer and a cladding layer C positioned at the tail end of a waveguide, wherein a wedge-shaped block facing the inlet direction of a channel is arranged in front of a branch point of the Y-branch waveguide, an input light source of the laser is coupled into a micro-fluidic chip through an optical fiber, and the position and the width of fluid in the core layer are changed to realize dynamic adjustment of the splitting ratio by controlling the flow of the fluid through the fluid control system.

Preferably, the working region of the Y-branch waveguide is 1900 μm long, 430 μm wide and 125 μm high.

Preferably, the cladding A, the cladding B and the cladding C are filled with glycol, and the core layer is filled with cinnamaldehyde.

Preferably, the wedge has a tip angle of 15 °, a length of 500 μm and a width of 130 μm.

Preferably, the Y-branch waveguide comprises a main channel and two branch channels, and each branch channel forms an angle of 27 ° with the main channel.

Preferably, the fluid control system is implemented by a dual channel syringe pump.

Preferably, the cross sections of the core layer, the cladding layer A, the cladding layer B and the cladding layer C are all rectangular.

The technical scheme provided by the invention has the beneficial effects that: according to the invention, the PDMS micro-fluidic chip is used for constructing the fluid optical waveguide, so that the micro-fluidic adjustable beam splitter is obtained, and a larger splitting ratio adjusting range is realized. The manufacturing process is simple and the implementation cost is low.

Drawings

The invention will be further described with reference to the accompanying drawings and examples, in which:

FIG. 1 is a block diagram of an apparatus for a microfluidic based tunable beam splitter according to an embodiment of the present invention;

FIG. 2 is a diagram illustrating fluid flow conditions for different splitting ratios according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of the calculation of the splitting ratio according to the embodiment of the present invention;

FIG. 4 is a diagram illustrating dynamic changes in split ratio during a flow change process according to an embodiment of the present invention;

FIG. 5 shows the change in the splitting ratio when the core flow is 40 μ L/min, the cladding flow is 20 μ L/min, and the cladding B is increased from 2 μ L/min to 38 μ L/min, according to an embodiment of the present invention.

Detailed Description

For a more clear understanding of the technical features, objects and effects of the present invention, embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

Referring to fig. 1, fig. 1 is a schematic diagram of an apparatus of a microfluidic-based adjustable beam splitter according to an embodiment of the present invention, where fig. 1(a) is a schematic diagram of the beam splitter and fig. 1(b) is a schematic diagram of an apparatus for verifying a splitting ratio;

the invention provides a microfluidic-based adjustable beam splitter, comprising: a Laser (Laser), a fluid control system, a Y-branch waveguide, and an inverted fluorescence Microscope (Microscope) with CCD;

the Y-branch waveguide is a micro-fluidic chip which is made by inverse molding PDMS on a silicon chip, is symmetrical about a horizontal line, and comprises: the Core layer (Core), the cladding A (clipping A) that is located the Core layer top, the cladding B (clipping B) that is located the Core layer below, the cladding C (clipping C) that is located the waveguide end, set up a Wedge (Wedge) towards the passageway entry direction before the branch point of Y branch waveguide, Laser (Laser) input light source passes through the fiber coupling to the micro-fluidic chip in, through the flow size of fluid control system control fluid, change the position and the width of Core layer fluid in order to realize the dynamic adjustment beam split and compare.

In this embodiment, the Y-branch waveguide has an operating region length of 1900 μm, a width of 430 μm, and a height of 125 μm.

In this embodiment, ethylene glycol is introduced into the clad layers a, B and C, and cinnamaldehyde is introduced into the core layer.

In this embodiment, the wedge has a tip angle of 15 °, a length of 500 μm and a width of 130 μm.

In this embodiment, the Y-branch waveguide includes a main channel and two branch channels, and each of the branch channels forms an angle of 27 ° with the main channel.

In this embodiment, the fluid control system is implemented by a dual channel syringe Pump (Pump).

In this embodiment, the cross-sections of the core layer, the cladding layer a, the cladding layer B, and the cladding layer C are all rectangular, and the shapes thereof may be adjusted according to specific situations.

As an alternative embodiment, the model number of the double channel injection pump is: LEAD fluuid TYD 02-02.

As an alternative embodiment, the model of the inverted fluorescence microscope with CCD is: SHUOGUANG CFM-500E.

Referring to fig. 2, fig. 2 is a diagram of fluid flow conditions corresponding to different splitting ratios according to an embodiment of the present invention. Wherein FIG. 2(a) is the fluid flow regime at a split ratio of 1: 1; FIG. 2(b) is the fluid flow regime at a split ratio of 1: 0; fig. 2(c) shows the state of fluid flow at a spectroscopic ratio of 0: 1. The input light source is provided by a laser and coupled into the chip through an optical fiber, and the position and the width of the core layer fluid are changed by controlling the flow of the fluid pumped by the four double-channel injection pumps so as to achieve the effect of dynamically changing the splitting ratio.

Referring to FIG. 3, FIG. 3 is a schematic diagram illustrating the calculation of the splitting ratio according to an embodiment of the present invention;

in order to verify that the fluid optical waveguide provided by the invention can obtain a larger splitting ratio adjustment range, an experiment is designed to quantitatively analyze the dynamic splitting ratio adjustment range. In order to better observe the change of the splitting ratio in the experiment, rhodamine 6G is added into cinnamaldehyde, and a laser with the wavelength of 532nm is used for exciting fluorescence. An inverted fluorescence microscope (model: SHUOGUANG CFM-500E) with a CCD is adopted to observe the light path, capture a fluorescence image and calculate the light splitting ratio. I1 is the light intensity accumulated value in the upper half of the vertical broken line in the figure, and I2 is the light intensity accumulated value in the lower half of the vertical broken line in the figure. The calculation method of the splitting ratio comprises the following steps: and R is I1/(I1+ I2).

Referring to fig. 4, fig. 4 is a graph illustrating dynamic changes of the split ratio during the flow rate change process according to the embodiment of the present invention; wherein, FIG. 4(a) shows the change of the splitting ratio in the process of increasing the core flow rate to 40 μ L/min, the cladding flow rate to 20 μ L/min, and the cladding flow rate to 24 μ L/min; FIG. 4(B) is a graph showing the change in the spectral ratio during an increase in the core flow rate of 100. mu.L/min, the cladding flow rate of 20. mu.L/min for cladding C, and the cladding B from 8. mu.L/min to 32. mu.L/min; FIG. 4(C) shows the change in the spectral ratio during the increase of the core flow rate to 160. mu.L/min, the clad flow rate to 20. mu.L/min, and the clad flow rate to 38. mu.L/min.

The core flow (Q2) was adjusted to 40. mu.L/min and the cladding C flow was adjusted to 20. mu.L/min by syringe pump. During the experiment, the width of the core layer can be kept constant by changing the flow rate of the cladding layers while keeping the flow rates of the cladding layers A and B constant. For example, when the sum of the flow rates of the clad layers is maintained at 40. mu.L/min and the flow rate of the clad layer B (Q3) is 16. mu.L/min, the flow rate of the clad layer A is 24. mu.L/min, and when the flow rate of the clad layer B is increased to 18. mu.L/min, the flow rate of the clad layer A is 22. mu.L/min. As can be seen from fig. 4, as the flow rate of the core layer increases, the range of variation of the splitting ratio becomes smaller. This indicates that the beam splitter can achieve a larger tuning range of the splitting ratio at a lower core flow rate.

Referring to FIG. 5, FIG. 5 shows the change in the split ratio during the increase of cladding B from 2 μ L/min to 38 μ L/min when the core flow is 40 μ L/min and the cladding C flow is 20 μ L/min, according to an embodiment of the present invention.

Taking the core layer flux as 40 μ L/min for example, the flux of the cladding layer B is gradually increased from 2 μ L/min to 38 μ L/min in steps of 2, and the corresponding splitting ratio is dynamically adjusted from 0 to 1. This experiment demonstrates that the microfluidic-based tunable beam splitter of the present invention has an excellent dynamic tuning range for splitting ratio.

While the present invention has been described with reference to the embodiments shown in the drawings, the present invention is not limited to the embodiments, which are illustrative and not restrictive, and it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the invention as defined in the appended claims.