阅读说明：本技术 光学结构及其制作方法、光源系统、以及检测装置 (Optical structure, manufacturing method thereof, light source system and detection device ) 是由 孟宪芹 王维 谭纪风 孟宪东 陈小川 高健 王方舟 梁蓬霞 于 2018-07-31 设计创作，主要内容包括：本公开提供了一种光学结构及其制作方法、光源系统、以及检测装置,简化了光谱测试的基础结构及其制作方法。所述光学结构包括：用于传导光的光波导,所述光波导包括入光面和出光面；布置在所述光波导的出光面处的分色器件,所述分色器件配置为将来自所述光波导的光分离成多个单色光束；以及布置在所述分色器件的出光面处的多个单色光输出通道,所述多个单色光输出通道配置为输出来自所述分色器件的多个单色光束。(The present disclosure provides an optical structure and a method of fabricating the same, a light source system, and a detection apparatus, simplifying a basic structure of a spectrum test and a method of fabricating the same. The optical structure includes: the optical waveguide is used for transmitting light and comprises a light inlet surface and a light outlet surface; a color separation device disposed at the light exit surface of the optical waveguide, the color separation device configured to separate light from the optical waveguide into a plurality of monochromatic light beams; and a plurality of monochromatic light output channels arranged at the light exit surface of the color separation device, the plurality of monochromatic light output channels being configured to output a plurality of monochromatic light beams from the color separation device.)

1. An optical structure comprising:

the optical waveguide is used for transmitting light and comprises a light inlet surface and a light outlet surface;

a color separation device disposed at the light exit surface of the optical waveguide, the color separation device configured to separate light from the optical waveguide into a plurality of monochromatic light beams; and

a plurality of monochromatic light output channels disposed at a light exit surface of the color separation device, the plurality of monochromatic light output channels configured to output a plurality of monochromatic light beams from the color separation device.

2. The optical structure of claim 1 wherein the optical waveguide, the dichroic device, and the plurality of monochromatic light output channels are disposed in the same layer.

3. An optical structure as claimed in claim 1, wherein each monochromatic light output channel is a sub-optical waveguide.

4. The optical structure of claim 1, further comprising: an upper cladding layer disposed on the upper surface of the optical waveguide and/or a lower cladding layer disposed on the lower surface of the optical waveguide; the refractive index of the upper cladding and the refractive index of the lower cladding are lower than the refractive index of the optical waveguide.

5. The optical structure of claim 4, wherein the optical structure comprises a lower cladding layer disposed on a lower surface of the optical waveguide; the lower cladding is a substrate; the optical waveguide, the color separation device, and the plurality of monochromatic light output channels are arranged on the substrate.

6. An optical structure as claimed in any one of claims 1 to 5, wherein the optical waveguide, the dichroic device, and the plurality of monochromatic light output channels are of the same material.

7. An optical structure as claimed in any one of claims 1 to 5, wherein the dichroic device is a reflective blazed grating; the grating surface of the reflective blazed grating faces the light-emitting surface of the optical waveguide.

8. The optical structure of claim 7, further comprising: a reflective layer disposed outside of the grating face.

9. The optical structure of any one of claims 1-5, wherein the light incident surface of the optical waveguide is provided with a slanted surface or a transmissive grating for input light.

10. An optical structure as claimed in any one of claims 1 to 5, wherein the light exit surface of each monochromatic light output channel is provided with a dot or extraction grating for outputting a monochromatic light beam.

11. A light source system comprising an optical structure according to any one of claims 1-10 and a light source; the light emitting surface of the light source faces the light incident surface of the optical waveguide.

12. A detection device comprising an optical structure according to any one of claims 1-10 and a detection structure disposed opposite the optical structure; wherein the detection structure comprises a microfluidic channel and a plurality of light sensing units; the plurality of monochromatic light output channels are arranged on one side of the microfluidic channel; the plurality of light sensing units are arranged on the opposite side of the microfluidic channel from the plurality of monochromatic light output channels; the light receiving surface of each light sensing unit faces the light emitting surface of one monochromatic light output channel.

13. The detection device of claim 12, wherein the detection structure further comprises a second substrate on which the plurality of light sensing units and the microfluidic channel are disposed.

14. The detection apparatus according to claim 12, wherein the optical waveguide, the color separation device, the plurality of monochromatic light output channels, the microfluidic channel, and the plurality of light sensing units are disposed on the same substrate.

15. A method of fabricating an optical structure, comprising:

forming an optical waveguide for transmitting light, wherein the optical waveguide comprises a light-in surface and a light-out surface;

forming a dichroic device at a light exit surface of the optical waveguide, the dichroic device configured to separate light from the optical waveguide into a plurality of monochromatic light beams; and

and a plurality of monochromatic light output channels are formed at the light emergent surface of the color separation device and configured to output a plurality of monochromatic light beams from the color separation device.

16. The method of claim 15, further comprising: forming an upper cladding layer and/or a lower cladding layer; the upper cladding layer is arranged on the upper surface of the optical waveguide layer, the lower cladding layer is arranged on the lower surface of the optical waveguide layer, and the refractive index of the upper cladding layer and the refractive index of the lower cladding layer are smaller than that of the optical waveguide layer.

17. The method of claim 16, wherein the step of forming the lower cladding layer comprises: providing a substrate;

the step of forming the optical waveguide, the color separation device and the plurality of monochromatic light output channels comprises: and forming a first material layer on the substrate, and performing a primary patterning process on the first material layer to form the optical waveguide, the color separation device and the plurality of monochromatic light output channels.

18. The method of claim 15, wherein forming a dichroic device at the exit face of the optical waveguide comprises:

and forming a reflective blazed grating by utilizing a nano-imprinting process, wherein the grating surface of the reflective blazed grating faces the light-emitting surface of the optical waveguide.

Technical Field

The present disclosure relates to the field of optical detection technologies, and in particular, to an optical structure, a manufacturing method thereof, a light source system, and a detection device.

Background

Substance calibration or quantitative analysis can be achieved by utilizing the reflection, transmission or absorption of light with specific wavelength by the microfluid. However, existing spectrometer devices are often too bulky to be used in a laboratory. It is therefore desirable to provide a miniaturized spectrometer, increase the spectral range of the spectrometer, reduce the cost of the spectrometer, and thereby increase the range of use of the spectrometer.

Disclosure of Invention

The present disclosure provides an optical structure and a method of fabricating the same, a light source system, and a detection apparatus, simplifying a basic structure of a spectrum test and a method of fabricating the same.

According to one aspect of the present disclosure, an optical structure is provided. The optical structure includes: the optical waveguide is used for transmitting light and comprises a light inlet surface and a light outlet surface; a color separation device disposed at the light exit surface of the optical waveguide, the color separation device configured to separate light from the optical waveguide into a plurality of monochromatic light beams; and a plurality of monochromatic light output channels arranged at the light exit surface of the color separation device, the plurality of monochromatic light output channels being configured to output a plurality of monochromatic light beams from the color separation device.

Optionally, in some embodiments, the optical waveguide, dichroic device, and plurality of monochromatic light output channels are arranged in the same layer.

Optionally, in some embodiments, each monochromatic light output channel is a sub-optical waveguide.

Optionally, in some embodiments, the optical structure further comprises: an upper cladding layer disposed on the upper surface of the optical waveguide and/or a lower cladding layer disposed on the lower surface of the optical waveguide; the refractive index of the upper cladding and the refractive index of the lower cladding are lower than the refractive index of the optical waveguide.

Optionally, in some embodiments, the optical structure includes a lower cladding layer disposed on a lower surface of the optical waveguide; the lower cladding is a substrate; the optical waveguide, the color separation device, and the plurality of monochromatic light output channels are arranged on the substrate.

Optionally, in some embodiments, the optical waveguide, the dichroic device, and the plurality of monochromatic light output channels are of the same material.

Optionally, in some embodiments, the dichroic device is a reflective blazed grating; the grating surface of the reflective blazed grating faces the light-emitting surface of the optical waveguide.

Optionally, in some embodiments, the optical structure further comprises: a reflective layer disposed outside of the grating face.

Optionally, in some embodiments, the light incident surface of the optical waveguide is provided with an inclined surface or a transmissive grating for inputting light.

Optionally, in some embodiments, the light emitting surface of each monochromatic light output channel is provided with a mesh point or an extraction grating for outputting a monochromatic light beam.

According to another aspect of the present disclosure, a light source system is provided. The light source system comprises the optical structure as described in any of the above embodiments and a light source; the light emitting surface of the light source faces the light incident surface of the optical waveguide.

According to yet another aspect of the present disclosure, a detection apparatus is provided. The detection device comprises the optical structure and a detection structure arranged opposite to the optical structure, wherein the optical structure is arranged on the detection device; wherein the detection structure comprises a microfluidic channel and a plurality of light sensing units; the plurality of monochromatic light output channels are arranged on one side of the microfluidic channel; the plurality of light sensing units are arranged on the opposite side of the microfluidic channel from the plurality of monochromatic light output channels; the light receiving surface of each light sensing unit faces the light emitting surface of one monochromatic light output channel.

Optionally, in some embodiments, the detection structure further comprises a second substrate on which the plurality of light sensing units and the microfluidic channel are arranged.

Optionally, in some embodiments, the optical waveguide, the color separation device, the plurality of monochromatic light output channels, the microfluidic channel, and the plurality of light sensing units are disposed on the same substrate.

According to another aspect of the present disclosure, a method of fabricating an optical structure is provided. The method comprises the following steps: forming an optical waveguide for transmitting light, wherein the optical waveguide comprises a light-in surface and a light-out surface; forming a dichroic device at a light exit surface of the optical waveguide, the dichroic device configured to separate light from the optical waveguide into a plurality of monochromatic light beams; forming a plurality of monochromatic light output channels at the light emitting surface of the color separation device, wherein the plurality of monochromatic light output channels are configured to output a plurality of monochromatic light beams from the color separation device; wherein the optical waveguide, the color separation device, and the plurality of monochromatic light output channels are arranged in the same layer.

Optionally, in some embodiments, the method further comprises: forming an upper cladding layer and/or a lower cladding layer; the upper cladding layer is arranged on the upper surface of the optical waveguide layer, the lower cladding layer is arranged on the lower surface of the optical waveguide layer, and the refractive index of the upper cladding layer and the refractive index of the lower cladding layer are smaller than that of the optical waveguide layer.

Optionally, in some embodiments, the step of forming the lower cladding layer comprises: providing a substrate; the step of forming the optical waveguide, the color separation device and the plurality of monochromatic light output channels comprises: and forming a first material layer on the substrate, and performing a primary patterning process on the first material layer to form the optical waveguide, the color separation device and the plurality of monochromatic light output channels.

Optionally, in some embodiments, the step of forming a dichroic device at the light exit surface of the optical waveguide includes: and forming a reflective blazed grating by utilizing a nano-imprinting process, wherein the grating surface of the reflective blazed grating faces the light-emitting surface of the optical waveguide.

Drawings

In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present disclosure, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a top view of an optical structure according to an embodiment of the present disclosure;

FIG. 2 is a cross-sectional view of the optical structure shown in FIG. 1 taken along line A-A';

FIG. 3 is a top view of an optical structure according to another embodiment of the present disclosure;

FIG. 4 is a schematic view of a partial structure of a monochromatic light output channel according to an embodiment of the present disclosure;

FIG. 5 is a cross-sectional view of a fingerprint identification device according to another embodiment of the present disclosure;

FIG. 6 is a cross-sectional view of a detection device according to an embodiment of the present disclosure;

FIG. 7 is a top view of the sensing structure in the embodiment of FIG. 6;

FIG. 8 is a top view of a detection structure according to another embodiment of the present disclosure;

FIGS. 9a-9c are schematic structural views of steps of a method of fabricating an optical structure according to an embodiment of the present disclosure; and

fig. 10a-10g are schematic structural views of steps of a method of fabricating an optical structure according to another embodiment of the present disclosure.

Detailed Description

The technical solutions in the embodiments of the present disclosure will be clearly and completely described below with reference to the drawings in the embodiments of the present disclosure, and it is obvious that the described embodiments are only a part of the embodiments of the present disclosure, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments disclosed herein without making any creative effort, shall fall within the protection scope of the present disclosure.

According to one aspect of the present disclosure, an optical structure is provided. As shown in fig. 1 and 2, the optical structure 100 includes: an optical waveguide 101 for guiding light (as indicated by arrow 10 in fig. 1), the optical waveguide including a light incident surface 1011 and a light exiting surface 1012; a color separation device 102 disposed at the light exit surface 1012 of the optical waveguide 101, the color separation device 102 being configured to separate light from the optical waveguide 101 into a plurality of monochromatic light beams; and a plurality of monochromatic light output channels 103 arranged at the light exit surface of the color separation device, the plurality of monochromatic light output channels 103 configured to output a plurality of monochromatic light beams from the color separation device 102; wherein the optical waveguide 101, the dichroic device 102, and the plurality of monochromatic light output channels 103 are arranged in the same layer.

In embodiments of the present disclosure, an optical structure includes an optical waveguide, a dichroic device, and a plurality of monochromatic light output channels arranged in the same layer, simplifying the basic structure of spectral testing and the method of making the same. The optical structure of the embodiment of the disclosure can be applied to the fields of physics, chemistry, biology, medicine, agriculture and the like, and is used for substance analysis or molecular analysis.

In the context of the present disclosure, two or more objects "arranged in the same layer" means that the two or more objects are provided on the same surface or in the same layer. In some embodiments of the present disclosure, two or more objects "disposed in the same layer" also indicates that the two or more objects are formed from the same layer of material (e.g., without limitation, via a patterning process).

Thus, in some embodiments, as shown in fig. 2 and 6, the optical waveguide 101, the dichroic device 102, and the plurality of monochromatic light output channels 103 are arranged in the same layer. Alternatively, the optical waveguide 101, the dichroic device 102, and the plurality of monochromatic light output channels 103 are located on the same surface or in the same layer. Alternatively, the optical waveguide 101, the dichroic device 102, and the plurality of monochromatic light output channels 103 are formed of the same layer of material.

Alternatively, in some embodiments, as shown in fig. 1-6 and 8, each of the monochromatic light output channels is a sub-optical waveguide.

Optionally, in some embodiments, as shown in fig. 2, the optical structure 100 further includes: an upper cladding layer 104 disposed on the upper surface of the optical waveguide 101 and/or a lower cladding layer 105 disposed on the lower surface of the optical waveguide 101; the refractive index of the upper cladding 104 and the refractive index of the lower cladding 105 are lower than the refractive index of the optical waveguide 101.

By arranging the upper cladding layer and/or the lower cladding layer according to the principle of total internal reflection, light entering the optical waveguide can be more effectively confined in the optical waveguide. Thereby, the light utilization efficiency is improved. In addition, the upper cladding layer and the lower cladding layer can also serve as protective layers to prevent damage to the optical waveguide.

Optionally, in some embodiments, as shown in fig. 1 and 2, the optical structure 100 includes a lower cladding layer 105 disposed on a lower surface of the optical waveguide 101; the lower cladding 105 is a substrate; the optical waveguide 101, the color separation device 102, and the plurality of monochromatic light output channels 103 are disposed on the substrate.

With the above arrangement, the material layer arranged on the substrate can be patterned using, for example, a patterning process, thereby obtaining the optical waveguide, the color separation device, and the plurality of monochromatic light output channels. Therefore, the basic structure of the spectrum test and the manufacturing method thereof are further simplified.

Optionally, in some embodiments, the materials of the optical waveguide 101, the dichroic device 102, and the plurality of monochromatic light output channels 103 are the same.

In some embodiments, the optical waveguide, the dichroic device, and the plurality of monochromatic light output channels are formed using the same material. For example, it can be on a glass substrate or SiO ₂Silicon nitride (SiNx) is used on the substrate to manufacture the optical waveguide, the color separation device and the plurality of monochromatic light output channels. Specifically, a layer of silicon nitride may be formed on a glass substrate and then patterned using a patterning process, thereby obtaining the optical waveguide 101, the color separation device 102, and the plurality of monochromatic light output channels 103 as shown in fig. 1. Due to the fact thatThe refractive index of glass is about 1.52 and the refractive index of silicon nitride is about 1.9, so that the light beam can be effectively confined in the optical waveguide, the dichroic device, and the plurality of monochromatic light output channels. Therefore, the basic structure of the spectrum test and the manufacturing method thereof are further simplified.

Alternatively, in some embodiments, as shown in fig. 1, the dichroic device 102 is a reflective blazed grating; the grating surface 1021 of the reflective blazed grating faces the light exit surface 1012 of the optical waveguide.

With the above arrangement, light from the optical waveguide is incident on the grating face. The grating surface separates light from the optical waveguide into a plurality of monochromatic light beams. As shown in fig. 1, a plurality of different line types represent a plurality of monochromatic light beams having different wavelengths. In the embodiment shown in fig. 1, the light incident surface and the light emitting surface of the reflective blazed grating are adjacent to each other. The light incident surface of the reflective blazed grating is coupled with the light emergent surface 1012 of the optical waveguide 101, and the light emergent surface of the reflective blazed grating is coupled with the light incident surfaces of the plurality of monochromatic light output channels 103. The above-described arrangement is only one embodiment and does not limit the present invention. For example, the positions of the light incident surface and the light emitting surface of the reflective blazed grating can be adjusted according to actual needs.

Alternatively, the color separation device may also be a holographic grating. The holographic grating can be designed and optimized corresponding to different incidence angles and positions to obtain gratings with different parameters. Alternatively, the color separation device may be a linear gradient filter or the like. The light exit surface of the color separation device is arranged such that the separated plurality of monochromatic light beams is coupled to the plurality of monochromatic light output channels 103.

Optionally, in some embodiments, as shown in fig. 1 and 2, the optical structure 100 further comprises: a reflective layer 106 disposed on an outer side of the grating face 1021.

With the arrangement, the light utilization rate of the reflective blazed grating is further improved. The reflective layer 106 may be formed on the outside of the grating face 1021 using, for example, a sputtering process. The material of the reflective layer 106 may be aluminum, silver, or other reflective material.

Optionally, in some embodiments, as shown in fig. 1, a transmissive grating 107 for inputting light is disposed on the light incident surface 1011 of the optical waveguide 101. The transmissive grating 107 may be fabricated using, for example, a nanoimprint process to increase the dispersion of the incident light, further enhancing the color separation effect of the color separation device 102. In some embodiments, as shown in fig. 3, the light incident surface 1011 of the light waveguide 101 is provided with an inclined surface for inputting light. The slope may be designed according to the direction of incident light and the position of the light source so that the incident light enters the optical waveguide 101 at a desired angle.

Optionally, in some embodiments, as shown in fig. 4, the light exit surface 1031 of each monochromatic light output channel 103 is provided with a mesh 1032 or an extraction grating 1033 for outputting a monochromatic light beam. In the embodiment of fig. 4, a monochromatic light beam can be extracted from the light exit surface 1031 at the bottom of the monochromatic light output channel 103 using the mesh 1032 or extraction grating 1033, i.e., the extracted monochromatic light beam exits toward the lower cladding 105. Alternatively, it is also possible to arrange a slope at the light exit surface of each monochromatic light output channel, so that the monochromatic light beams leave the monochromatic light output channel 103 in a desired direction.

According to another aspect of the present disclosure, a light source system is provided. As shown in fig. 5, the light source system 200 includes the optical structure according to any of the above embodiments.

The light source system can be used as a light source of a micro spectrometer, so that the thickness and the volume of the micro spectrometer are effectively reduced. In addition, the light source system may be fabricated based on a glass substrate and a patterning process, and thus the light source system having desired parameters may be fabricated using the patterning process, further improving the compatibility of the light source system.

Optionally, in some embodiments, as shown in fig. 5, the light source system 200 further comprises a light source 201; the light emitting surface of the light source 201 faces the light incident surface 1011 of the light waveguide 101.

The light source 201 may be a light emitting diode or a composite light source consisting of a plurality of light emitting diodes (or laser diodes) to provide polychromatic light with a certain spectral range to the optical structure. Those skilled in the art will appreciate that the light source system 200 may also utilize sunlight or ambient light as incident light to obtain a plurality of monochromatic light beams via the optical structure.

According to yet another aspect of the present disclosure, a detection apparatus is provided. As shown in fig. 6, the detection apparatus 300 includes the optical structure 100 according to any of the above embodiments and the detection structure 150 disposed opposite to the optical structure. In the embodiment of fig. 6, the optical structure 100 is the arrangement shown in fig. 1 and 2, but the optical structure in the present disclosure is not limited thereto. As shown in fig. 6 and 7, the detection structure 150 includes a microfluidic channel 151 and a plurality of light sensing units 152; the plurality of monochromatic light output channels 103 are arranged on one side of the microfluidic channel 151; the plurality of light sensing units 152 are arranged on the opposite side of the microfluidic channel 151 from the plurality of monochromatic light output channels 103; the light receiving surface 1521 of each light sensing unit 152 faces the light exit surface 1031 of one of the monochromatic light output channels 103.

In some embodiments, the plurality of light sensing units 152 correspond one-to-one to the plurality of monochromatic light output channels 103. Each light sensing unit 152 may include one or more light sensors. The monochromatic light beam output by each monochromatic light output channel 103 will change in intensity or wavelength after passing through the microfluidic channel 151. With the light sensing unit 152 corresponding to the monochromatic light output channel 103, it is possible to obtain variation information of the monochromatic light beam, thereby obtaining a spectral measurement result.

Optionally, in some embodiments, as shown in fig. 6 and 7, the detection structure 150 further comprises a second substrate 153 on which the plurality of light sensing units 152 and the microfluidic channel 151 are disposed.

In the embodiments shown in fig. 6 and 7, the optical structure 100 and the detection structure 150 are arranged in a stack, so that a plurality of light sensing units 152 shown in fig. 6 are arranged below said microfluidic channel 151. Alternatively, the optical structure 100 and the detection structure 150 may be arranged on the same side of the substrate. For example, in some embodiments, as shown in fig. 8, the optical waveguide 101, the dichroic device 102, the plurality of monochromatic light output channels 103, the microfluidic channel 151, and the plurality of light sensing units 152 are all disposed on the same side of the substrate 108.

Furthermore, in the embodiment shown in fig. 8, the optical waveguide 101, the dichroic device 102, the plurality of monochromatic light output channels 103, the microfluidic channel 151 and the plurality of light sensing units 152 may be on the same substrate, preferably arranged in the same layer. For example, a pattern of the optical waveguide 101, the color separation device 102, the plurality of monochromatic light output channels 103, and the microfluidic channel 151 may be formed on the surface of the substrate 108 using, for example, a patterning process, and then the plurality of light sensing units 152 may be disposed at one side of the microfluidic channel 151. Wherein the pattern of microfluidic channels 151 comprises two parallel walls and a groove between the two walls. A hydrophobic layer or a hydrophilic layer may be disposed inside the microfluidic channel 151 (i.e., the surface of the groove) to allow the microfluid to flow or temporarily stay within the microfluidic channel 151 as needed. For example, a teflon-AF hydrophobic layer can make the microfluid as non-stick to the microfluidic channel as much as possible, enhancing the fluidity of the microfluid.

According to another aspect of the present disclosure, a method of fabricating an optical structure is provided. The method comprises the following steps: forming an optical waveguide for transmitting light, wherein the optical waveguide comprises a light-in surface and a light-out surface; forming a dichroic device at a light exit surface of the optical waveguide, the dichroic device configured to separate light from the optical waveguide into a plurality of monochromatic light beams; forming a plurality of monochromatic light output channels at the light emitting surface of the color separation device, wherein the plurality of monochromatic light output channels are configured to output a plurality of monochromatic light beams from the color separation device; wherein the optical waveguide, the color separation device, and the plurality of monochromatic light output channels are arranged in the same layer.

In embodiments of the present disclosure, an optical structure includes an optical waveguide, a dichroic device, and a plurality of monochromatic light output channels arranged in the same layer, simplifying the basic structure of spectral testing and the method of making the same. The optical structure of the embodiment of the disclosure can be applied to the fields of physics, chemistry, biology, medicine, agriculture and the like, and is used for substance analysis or molecular analysis.

For example, the substrate may be a glass substrate having a thickness of 0.5 to 0.7mm and a length and width of 10mm by 10mm, respectively. A micro spectrometer can thus be realized on a glass substrate with dimensions of about 10mm x 10mm by means of a patterning process.

Optionally, in some embodiments, the method further comprises: forming an upper cladding layer and/or a lower cladding layer; the upper cladding layer is arranged on the upper surface of the optical waveguide layer, the lower cladding layer is arranged on the lower surface of the optical waveguide layer, and the refractive index of the upper cladding layer and the refractive index of the lower cladding layer are smaller than that of the optical waveguide layer.

By arranging the upper cladding layer and/or the lower cladding layer according to the principle of total internal reflection, light entering the optical waveguide can be more effectively confined in the optical waveguide. Thereby, the light utilization efficiency is improved. In addition, the upper cladding layer and the lower cladding layer can also serve as protective layers to prevent damage to the optical waveguide.

Alternatively, as shown in fig. 9a-9c, in some embodiments, the step of forming the lower cladding layer comprises: a substrate 108 is provided (fig. 9 a). The step of forming the optical waveguide, the color separation device and the plurality of monochromatic light output channels comprises: a first material layer 109 is formed on the substrate 108 (fig. 9b), and a patterning process is performed on the first material layer 109 to form the optical waveguide 101, the color separation device 102, and the plurality of single-color light output channels 103 (fig. 9 c).

For example, the substrate 108 is a glass substrate. The material of the first material layer 109 may be silicon nitride. Silicon nitride may be deposited on the surface of the substrate 108, an aluminum layer 110 for a hard mask may be deposited on the surface of the silicon nitride, and then a photoresist 111 may be spin coated (as shown in fig. 10 a).

A pattern corresponding to the optical waveguide 101, the color separation device 102 (e.g. a reflective blazed grating) and the plurality of monochromatic light output channels 103 is embossed on the photoresist by means of electron beam direct-write lithography (EBL) or Nanoimprint (NIP). The hard mask is etched by wet etching, and then the optical waveguide 101, the color separation device 102 and the plurality of monochromatic light output channels 103 are etched by dry etching (for example, ICP or reactive ion etching, RIE) (as shown in fig. 10 b).

To obtain a desired grating profile (e.g., steeper profile), a digital exposure process may be further used to expose the area that needs to be etched back (i.e., the peripheral area of the grating), thereby forming deep trenches in the peripheral area of the grating. The aluminum layer 110 may be used as a hard mask and a photoresist pattern 112 may be formed on the substrate (as shown in fig. 10 c). Deep trenches 113 are formed in the periphery of the grating using a photolithography process. The aluminum layer 110 is then removed (as shown in fig. 10 d).

To achieve a higher light utilization efficiency, a metal reflective layer 106 may be deposited on the outside of the grating face of the reflective blazed grating (as shown in fig. 10 e). The material of the metal reflective layer may be aluminum or silver. The metal reflective layer 106 deposited on the other areas can be removed using, for example, a photolithographic process (as shown in fig. 10 f).

Further, a resin 104 having a lower refractive index may be spin-coated on the upper surface of the optical waveguide 101. The resin 104 may further cover the light incident surface 1011 of the optical waveguide. The resin 104 may also form an inclined surface at the position of the light incident surface 1011 of the light guide, thereby improving the light input efficiency (as shown in fig. 10 g).

Optionally, in some embodiments, the step of forming a dichroic device at the light exit surface of the optical waveguide includes: and forming a reflective blazed grating by utilizing a nano-imprinting process, wherein the grating surface of the reflective blazed grating faces the light-emitting surface of the optical waveguide.

By using the nanoimprint process, the cost can be reduced, and the precision and the performance of the color separation device can be improved.

According to the optical structure, the manufacturing method of the optical structure, the light source system and the detection device, the optical structure comprises the optical waveguide, the color separation device and the plurality of monochromatic light output channels which are arranged in the same layer, and the basic structure for spectrum testing and the manufacturing method of the basic structure are simplified. The optical structure of the embodiment of the disclosure can be applied to the fields of physics, chemistry, biology, medicine, agriculture and the like, and is used for substance analysis or molecular analysis.

The above description is only a specific embodiment of the present disclosure, but the scope of the present disclosure is not limited thereto. Any person skilled in the art can easily conceive of changes or substitutions within the technical scope of the disclosure, and all the changes or substitutions are covered by the protection scope of the disclosure. Therefore, the protection scope of the present disclosure shall be subject to the protection scope of the claims.