CN117055150A - Waveguide array - Google Patents

Abstract

The application provides a waveguide array. The waveguide array comprises N waveguides, wherein N is larger than or equal to 2, N is a positive integer, and the optical path differences DeltaL of the N waveguides are in an arithmetic progression, and DeltaL is larger than or equal to 0; each waveguide comprises K sub-waveguides, and in the same waveguide, the K sub-waveguides are sequentially connected along a second direction, wherein K is more than or equal to 2, and K is a positive integer; the K sub-waveguides at least comprise M sub-waveguides with the same geometric parameters and different geometric parameters, wherein K is more than or equal to M, M and more than or equal to 2, and M is a positive integer; in the adjacent waveguides, the arrangement sequence of M sub-waveguides along the second direction is different; wherein the geometric parameter is any one of the parameters of the height, width, sidewall inclination angle and cross-sectional shape of the sub-waveguide.

Description

Waveguide array

Technical Field

The application belongs to the technical field of optical chips, and particularly relates to a waveguide array.

Background

In the theory of optical propagation of an optical waveguide, the optical path length of the optical waveguide is equal to the product of the geometric length of the waveguide and the effective refractive index of the transmission mode within the waveguide. In general, an optical chip structure is provided with a plurality of optical transmission waveguides, and if the optical paths of light transmitted by the plurality of optical waveguides are required to be equal or have a specific optical path difference, the structure of the waveguides is required to be specifically designed.

Miniaturization of optical chips is one of the most fundamental demands, so that the spacing between individual waveguides cannot be too large, but the spacing between individual waveguides cannot be too small, otherwise there is a problem of significant crosstalk between waveguides, i.e., a portion of the optical field is transmitted from one waveguide to the adjacent waveguide. Increasing the geometric difference between adjacent waveguides significantly reduces crosstalk when the spacing of the waveguides is small, but the geometric difference between the individual waveguides can result in a difference in optical path length. For example, for a highly fixed waveguide, the wider the waveguide, the greater the effective index. For a waveguide of fixed width, the higher the waveguide, the greater the effective index.

Miniaturization of optical chips requires smaller spacing and crosstalk between waveguides, which are difficult to meet at the same time. Although increasing the geometric difference between two adjacent waveguides can significantly suppress crosstalk even when the waveguide spacing is small, it is difficult to apply the method to a scene where a specific optical path difference (including zero optical path difference) between each waveguide is required. In the equal optical path design, the equal optical path can be realized by ensuring the equal geometric lengths under the condition that the cross section sizes of the waveguides are the same. If the cross-section sizes of the waveguides are different, the geometric length is required to be calculated, the calculation not only requires high precision and increases the design complexity of the optical chip, but also has objective deviation from the actual processing result.

Disclosure of Invention

The embodiment of the application aims to provide a waveguide array which can meet the requirements of small array interval and small crosstalk on the basis of equal optical path or specific optical path difference.

In order to achieve the above purpose, the application adopts the following technical scheme:

providing a waveguide array, wherein the waveguide array comprises N waveguides, the N waveguides are sequentially arranged at intervals in parallel along a first direction, N is more than or equal to 2, N is a positive integer, and the optical path differences DeltaL of the N waveguides are in an arithmetic progression, wherein DeltaL is more than or equal to 0;

each waveguide comprises K sub-waveguides, and in the same waveguide, the K sub-waveguides are sequentially connected along a second direction, wherein K is more than or equal to 2, and K is a positive integer; the K sub-waveguides at least comprise M sub-waveguides with the same geometric parameters and different parameters, wherein K is more than or equal to M, M and more than or equal to 2, and M is a positive integer; in the adjacent waveguides, the arrangement order of M sub-waveguides along the second direction is different;

wherein the geometric parameter is any one of the parameters of the height, width, sidewall inclination angle and cross-sectional shape of the sub-waveguide.

In one embodiment, the K sub-waveguides include at least M sub-waveguides having different width parameters.

In an embodiment, lengths of two adjacent waveguides are identical, geometric parameters of the 1 st sub-waveguide are identical, geometric parameters of the K-th sub-waveguide are identical, and identical geometric parameters of the 2 nd to the K-1 st sub-waveguides are all different, wherein Δl=0; in the same waveguide, the geometric parameters of the 1 st sub-waveguide and the K th sub-waveguide are the same.

In one embodiment, the lengths of two adjacent waveguides are in an arithmetic progression, the geometric parameters of the 1 st sub-waveguide in the two adjacent waveguides are the same, the lengths of the K-th sub-waveguide are in an arithmetic progression, and the same geometric parameters of the 2 nd to K-1 st sub-waveguides are all different, wherein DeltaL is more than 0.

In one embodiment, the width parameters of any position between the 2 nd to the K-1 st waveguiding in two adjacent waveguiding are different.

In one embodiment, the sub-waveguides include cylindrical sub-waveguides and tapered sub-waveguides, the width parameters of the cylindrical sub-waveguides are different, and the 1 st sub-waveguide and the k th sub-waveguide are cylindrical sub-waveguides; in the sub-waveguides from the 2 nd to the K-1 th, the cylindrical sub-waveguides and the conical sub-waveguides are alternately connected in turn, and the width parameters of the end parts of the conical sub-waveguides are consistent with the width parameters of the cylindrical waveguides connected with the conical sub-waveguides.

In one embodiment, the waveguide includes at least a first waveguide segment and a second waveguide segment electrically connected to the first waveguide segment, and the first waveguide segment and the second waveguide segment each include the K sub-waveguides;

the lengths of two adjacent waveguides are identical, in the two adjacent waveguides, the geometric parameters of the 1 st sub-waveguide of the first waveguide section are identical, the geometric parameters of the K th sub-waveguide are identical, the geometric parameters of the 1 st sub-waveguide of the second waveguide section are identical, and the geometric parameters of the K th sub-waveguide are identical;

in the same waveguide, the geometric parameters of the Kth sub-waveguide of the first waveguide section and the 1 st sub-waveguide of the second waveguide section are the same, and the geometric parameters of the 1 st sub-waveguide of the first waveguide section and the Kth sub-waveguide of the second waveguide section are the same;

in two adjacent waveguides, the same geometric parameters of the 2 nd to the K-1 th sub-waveguides in the first waveguide section are different, and the same geometric parameters of the 2 nd to the K-1 th sub-waveguides in the second waveguide section are different, wherein DeltaL=0.

In one embodiment, the waveguide includes at least a first waveguide segment and a second waveguide segment electrically connected to the first waveguide segment, and the first waveguide segment and the second waveguide segment each include the K sub-waveguides;

the lengths of two adjacent waveguides are in an arithmetic progression, in the two adjacent waveguides, the geometric parameters of the 1 st sub-waveguide of the first waveguide section are the same, the geometric parameters of the K th sub-waveguide are the same, the geometric parameters of the 1 st sub-waveguide of the second waveguide section are the same, and the geometric parameters of the K th sub-waveguide are in an arithmetic progression;

in the same waveguide, the geometric parameters of the Kth waveguide of the first waveguide section and the 1 st waveguide of the second waveguide section are the same;

in two adjacent waveguides, the same geometric parameters of the 2 nd to the K-1 th sub-waveguides in the first waveguide section are different, and the same geometric parameters of the 2 nd to the K-1 th sub-waveguides in the second waveguide section are different, wherein DeltaL is more than 0.

In one embodiment, the width parameters of any position of the sub-waveguides are different from each other in the sub-waveguides from the 2 nd to the K-1 st.

In an embodiment, the geometric parameters of the 1 st said sub-waveguide and the K-th said sub-waveguide of said first waveguide segment are the same or different.

In an embodiment, the 1 st sub-waveguide of the first waveguide section and the K st sub-waveguide of the second waveguide section are cylindrical waveguides, the K st sub-waveguide of the first waveguide section and the 1 st sub-waveguide of the second waveguide section are curved waveguides, the two curved waveguides are electrically connected through an electrical device, and the curved directions of the two curved waveguides are opposite.

In one embodiment, the sub-waveguides include a cylindrical sub-waveguide, a tapered sub-waveguide and a curved waveguide, the width parameters of the cylindrical sub-waveguides are different, the 1 st sub-waveguide of the first waveguide section and the K th sub-waveguide of the second waveguide section are both cylindrical sub-waveguides, and the K th sub-waveguide of the first waveguide section and the 1 st sub-waveguide of the second waveguide section are both curved sub-waveguides;

in the sub-waveguides from the 2 nd to the K-1 th, the cylindrical sub-waveguides and the conical sub-waveguides are alternately connected in turn, and the width parameters of the end parts of the conical sub-waveguides are consistent with the width dimensions of the cylindrical waveguides connected with the conical sub-waveguides; in adjacent ones of said waveguides, the total length of all said sub-waveguides of said first waveguide segment having identical parameter values in said 2 nd to K-1 th said sub-waveguides and said second waveguide segment having identical parameter values in said 2 nd to K-1 th said sub-waveguides.

The waveguide array provided by the application has the beneficial effects that:

compared with the prior art, the waveguide array provided by the application comprises N waveguides, the N waveguides are sequentially arranged at intervals in parallel along the first direction, the optical path differences DeltaL of the N waveguides are in an arithmetic progression, and the optical paths of light transmitted by the N waveguides are equal or have specific optical path differences. Each waveguide comprises K sub-waveguides, the K sub-waveguides are sequentially connected along the second direction in the same waveguide, at least M sub-waveguides with different geometric parameters are contained in the K sub-waveguides, and the arrangement sequence of the M sub-waveguides along the second direction in the adjacent waveguides is different. Wherein the geometric parameter is any one of the parameters of the height, width, sidewall inclination angle and cross-sectional shape of the sub-waveguide.

For the height parameter, the higher the height parameter of the sub-waveguide, i.e. the thicker the thickness of the sub-waveguide, the greater the effective refractive index of the sub-waveguide, with the other 3 geometrical parameters being the same. Therefore, in the two adjacent waveguides, the two parallel sub-waveguides on the same arrangement sequence have different heights, namely, the phase of the two sub-waveguides is difficult to match, and the crosstalk between the two sub-waveguides on the same arrangement sequence in the two adjacent waveguides can be effectively reduced.

For the width parameter, the higher the width parameter of the sub-waveguide, the greater the effective refractive index of the sub-waveguide, with all other 3 geometric parameters being the same. Therefore, in the two adjacent waveguides, the two parallel sub-waveguides on the same arrangement sequence have different widths, that is, the phases of the two sub-waveguides are difficult to match, and the crosstalk between the two sub-waveguides on the same arrangement sequence in the two adjacent waveguides can be effectively reduced.

For the sidewall tilt angle parameters, the smaller the sidewall tilt angle of the sub-waveguide, the larger the effective refractive index of the sub-waveguide, with the other 3 geometric parameters being the same. Since the cross-sectional shape of the sub-waveguide is trapezoidal when the sidewall inclination angle is smaller than 90 °, the smaller the sidewall inclination angle is, the larger the bottom is, and the larger the area of the trapezoid is, and the larger the effective refractive index of the sub-waveguide is, in the case that both the upper bottom dimension and the height dimension of the trapezoid of the sub-waveguide are identical. When the sidewall inclination angle is larger than 90 degrees, the cross section shape of the sub-waveguide is also trapezoid, and when the upper bottom size and the height size of the trapezoid of the sub-waveguide are consistent, the smaller the sidewall inclination angle is, the larger the lower bottom is, the larger the area of the trapezoid is, and the larger the effective refractive index of the sub-waveguide is. Therefore, in the two adjacent waveguides, the two parallel sub-waveguides on the same arrangement sequence have different side wall inclination angles, so that the phase of the two sub-waveguides is difficult to match, and the crosstalk between the two sub-waveguides on the same arrangement sequence in the two adjacent waveguides can be effectively reduced.

For the cross-sectional shape parameter, the cross-sectional shape also affects the effective index of the waveguide with the same other 3 geometric parameters. For example, the area of a sub-waveguide having a rectangular cross-sectional shape is larger than the area of a sub-waveguide having an elliptical cross-sectional shape, while the effective refractive index of the former is larger. Therefore, in the two adjacent waveguides, the two parallel sub-waveguides on the same arrangement sequence have different cross-sectional shapes, namely, the phases of the two parallel sub-waveguides are difficult to match, and the crosstalk between the two sub-waveguides on the same arrangement sequence in the two adjacent waveguides can be effectively reduced.

Therefore, in the waveguide array provided by the application, the same geometric parameters of M sub-waveguides in the K sub-waveguides of each waveguide are set to be different, and the arrangement sequence of the M sub-waveguides along the second direction is set to be different in two adjacent waveguides. In the two adjacent waveguides, the two parallel arranged sub-waveguides on the same arrangement sequence have different same geometric parameters, namely, the phase of the two parallel arranged sub-waveguides is difficult to match, namely, the crosstalk between the two sub-waveguides on the same arrangement sequence in the two adjacent waveguides can be effectively reduced, namely, the crosstalk between the two adjacent waveguides can be effectively reduced, the distance between the two adjacent waveguides can be set to be minimized based on the crosstalk, and the waveguide array is further densely arranged, so that the optical chip of the waveguide array provided by the application can be further miniaturized.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments or the description of the prior art will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic diagram of a waveguide array according to an embodiment of the present application, where Δl=0;

FIG. 2 is a schematic diagram of a waveguide array according to an embodiment of the present application, wherein ΔL > 0;

fig. 3 is a schematic diagram of a waveguide array according to an embodiment of the present application, where Δl=0.

Detailed Description

In order to make the technical problems, technical schemes and beneficial effects to be solved more clear, the application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the application.

It will be understood that when an element is referred to as being "mounted" or "disposed" on another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element.

It is to be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are merely for convenience in describing and simplifying the description based on the orientation or positional relationship shown in the drawings, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus are not to be construed as limiting the application.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present application, the meaning of "a plurality" is two or more, unless explicitly defined otherwise.

The waveguide array provided by the embodiment of the application will now be described.

Referring to fig. 1, fig. 2 and fig. 3, a waveguide array according to an embodiment of the present application is applied to an optical chip. The waveguide array comprises N waveguides, wherein the N waveguides are sequentially arranged at intervals in parallel along a first direction, N is more than or equal to 2, and N is a positive integer.

In the embodiment shown in fig. 1, 2 and 3, the first direction is referred to as the vertical direction, and N waveguides are sequentially arranged at intervals in parallel in the vertical direction. And the optical path differences delta L of the N waveguides are in an arithmetic progression, wherein delta L is more than or equal to 0. When Δl=0, the optical path difference of the N waveguides is 0, and it is understood that the optical paths of the light transmitted by the N waveguides are equal. When Δl > 0, the optical path difference of the N waveguides is greater than 0, and it is understood that the optical path of the light transmitted by the N waveguides has a specific optical path difference, and the value of the specific optical path difference is a positive number.

Further, each waveguide comprises K sub-waveguides, and in the same waveguide, the K sub-waveguides are sequentially connected along a second direction, wherein K is more than or equal to 2, and K is a positive integer. The K sub-waveguides at least comprise M sub-waveguides with the same geometric parameters and different geometric parameters, wherein K is more than or equal to M, M and more than or equal to 2, and M is a positive integer. In addition, in the adjacent waveguides, the M sub-waveguides are arranged in different orders along the second direction. Wherein the geometric parameter is any one of the parameters of the height, width, sidewall inclination angle and cross-sectional shape of the sub-waveguide.

For example, the same waveguide includes 6 sub-waveguides, and among the 6 sub-waveguides, 4 sub-waveguides having the same geometric parameter and different from each other may be contained, while the parameters of the other 2 sub-waveguides are identical. Alternatively, the same waveguide includes 6 sub-waveguides, and among the 6 sub-waveguides, 2 sub-waveguides having the same geometric parameter and different from each other may be included, and the parameters of the other 4 sub-waveguides are identical.

Wherein the geometric parameter is any one of a height parameter, a width parameter, a sidewall inclination angle parameter and a cross-sectional shape parameter of the sub-waveguide. In this embodiment, the K sub-waveguides may have 4 parameters, such as a height parameter, a width parameter, a sidewall inclination angle parameter, and a cross-sectional shape parameter. The K sub-waveguides at least contain M sub-waveguides with the same geometric parameters and different geometric parameters, namely that only one geometric parameter is different under the condition that the other 3 geometric parameters of the K sub-waveguides are identical.

For example, the same waveguide includes 6 sub-waveguides, among which the width parameter, the sidewall inclination angle parameter, and the cross-sectional shape parameter are all uniform, whereas 6 sub-waveguides include 4 sub-waveguides having different height parameters, and the height parameters of the other 2 sub-waveguides are uniform.

Alternatively, the same waveguide includes 6 sub-waveguides, and in the 6 sub-waveguides, the height parameter, the sidewall inclination angle parameter, and the cross-sectional shape parameter are all uniform, and the 6 sub-waveguides include 2 sub-waveguides having different width parameters, and the width parameters of the other 4 sub-waveguides are all uniform.

In one embodiment of the present application, it is preferable that at least M sub-waveguides having different width parameters are included in the K sub-waveguides, and the M sub-waveguides are arranged in different orders along the second direction in adjacent waveguides.

For the height parameter, the higher the height parameter of the sub-waveguide, i.e. the thicker the thickness of the sub-waveguide, the greater the effective refractive index of the sub-waveguide, with the other 3 geometrical parameters being the same. Therefore, in the two adjacent waveguides, the two parallel sub-waveguides on the same arrangement sequence have different heights, namely, the phase of the two sub-waveguides is difficult to match, and the crosstalk between the two sub-waveguides on the same arrangement sequence in the two adjacent waveguides can be effectively reduced.

For the width parameter, the higher the width parameter of the sub-waveguide, the greater the effective refractive index of the sub-waveguide, with all other 3 geometric parameters being the same. Therefore, in the two adjacent waveguides, the two parallel sub-waveguides on the same arrangement sequence have different widths, that is, the phases of the two sub-waveguides are difficult to match, and the crosstalk between the two sub-waveguides on the same arrangement sequence in the two adjacent waveguides can be effectively reduced.

For the sidewall tilt angle parameters, the smaller the sidewall tilt angle of the sub-waveguide, the larger the effective refractive index of the sub-waveguide, with the other 3 geometric parameters being the same. Since the cross-sectional shape of the sub-waveguide is trapezoidal when the sidewall inclination angle is smaller than 90 °, the smaller the sidewall inclination angle is, the larger the bottom is, and the larger the area of the trapezoid is, and the larger the effective refractive index of the sub-waveguide is, in the case that both the upper bottom dimension and the height dimension of the trapezoid of the sub-waveguide are identical. When the sidewall inclination angle is larger than 90 degrees, the cross section shape of the sub-waveguide is also trapezoid, and when the upper bottom size and the height size of the trapezoid of the sub-waveguide are consistent, the smaller the sidewall inclination angle is, the larger the lower bottom is, the larger the area of the trapezoid is, and the larger the effective refractive index of the sub-waveguide is. Therefore, in the two adjacent waveguides, the two parallel sub-waveguides on the same arrangement sequence have different side wall inclination angles, so that the phase of the two sub-waveguides is difficult to match, and the crosstalk between the two sub-waveguides on the same arrangement sequence in the two adjacent waveguides can be effectively reduced.

For the cross-sectional shape parameter, the cross-sectional shape also affects the effective index of the waveguide with the same other 3 geometric parameters. For example, the area of a sub-waveguide having a rectangular cross-sectional shape is larger than the area of a sub-waveguide having an elliptical cross-sectional shape, while the effective refractive index of the former is larger. Therefore, in the two adjacent waveguides, the two parallel sub-waveguides on the same arrangement sequence have different cross-sectional shapes, namely, the phases of the two parallel sub-waveguides are difficult to match, and the crosstalk between the two sub-waveguides on the same arrangement sequence in the two adjacent waveguides can be effectively reduced.

Therefore, in the waveguide array provided by the application, the same geometric parameters of M sub-waveguides in the K sub-waveguides of each waveguide are set to be different, and the arrangement sequence of the M sub-waveguides along the second direction is set to be different in two adjacent waveguides. In the two adjacent waveguides, the two parallel arranged sub-waveguides on the same arrangement sequence have different same geometric parameters, namely, the phase of the two parallel arranged sub-waveguides is difficult to match, namely, the crosstalk between the two sub-waveguides on the same arrangement sequence in the two adjacent waveguides can be effectively reduced, namely, the crosstalk between the two adjacent waveguides can be effectively reduced, the distance between the two adjacent waveguides can be set to be minimized based on the crosstalk, and the waveguide array is further densely arranged, so that the optical chip of the waveguide array provided by the application can be further miniaturized.

As shown in fig. 1, in one embodiment provided by the present application, the lengths of two adjacent waveguides are identical, the geometric parameters of the 1 st sub-waveguide in the two adjacent waveguides are identical, the geometric parameters of the K-th sub-waveguide are identical, and the same geometric parameters of the 2 nd to K-1 st sub-waveguides are all different, wherein Δl=0; in the same waveguide, the geometric parameters of the 1 st sub-waveguide and the K th sub-waveguide are the same.

In this embodiment, the width parameters of any position of the 2 nd to K-1 th sub-waveguides are preferably different in the adjacent two waveguides.

In this embodiment, the preferred sub-waveguide includes a cylindrical sub-waveguide and a tapered sub-waveguide, the 1 st sub-waveguide and the k th sub-waveguide are both cylindrical sub-waveguides, and the width parameters of the 1 st sub-waveguide and the k th sub-waveguide are the same. In the 2 nd to the K-1 th sub-waveguides, the cylindrical sub-waveguides and the tapered sub-waveguides are alternately connected in turn, and the width parameters of the end parts of the tapered sub-waveguides are consistent with those of the cylindrical waveguides connected with the tapered sub-waveguides.

Specifically, as shown in fig. 1, fig. 1 shows a straight waveguide array with equal optical paths, where each waveguide is sequentially arranged at intervals along a first direction, each waveguide extends along a second direction, and each waveguide has no bending area, so as to ensure that the lengths of the waveguides are equal, and thus, equal optical paths of light output by each waveguide can be achieved, and equal optical path difference is achieved by the waveguide array.

Specifically, the waveguide array shown in FIG. 1 comprises 3 waveguides, each waveguide comprising 6 sub-waveguides, the 6 sub-waveguides comprising 4 sub-waveguides of different widths, the 4 sub-waveguides comprising 2 sub-waveguides of different widths, the widths being set to 500nm and 600nm, respectively, using W ₅₀₀ And W is ₆₀₀ And (3) representing. Wherein 2 different width wavelets are connected by a tapered wavelet guide, respectively using T _500-600 And T _600-500 And (3) representing.

The widths of the input sub-waveguide and the output sub-waveguide of the 3 waveguides are 500nm, namely, the widths of the 1 st sub-waveguide and the k th sub-waveguide are 500nm, the widths of the parallel sub-waveguides which are arranged in the same arrangement sequence in two adjacent waveguides are different except for the input sub-waveguide and the output sub-waveguide, so that the phases of the sub-waveguides cannot be matched, crosstalk between the parallel sub-waveguides which are arranged in the same arrangement sequence can be effectively reduced, and the waveguide arrays can be arranged more tightly under the condition of the same crosstalk intensity.

Using L _in And L _out Representing the optical path length of the input and output sub-waveguides, respectively, L being used in addition to the input and output sub-waveguides ₅₀₀ And L ₆₀₀ Respectively represent sub-waveguides W ₅₀₀ And W is ₆₀₀ Uses L _500-600 And L _600-500 Respectively represent tapered sub-waveguides T _500-600 And T _600-500 Is provided). Thus, the total optical path length l=l of each waveguide _in +L ₅₀₀ +L ₆₀₀ +L _500-600 +L _600-500 +L _out . The total optical path length L of the 3 waveguides is equal as long as the optical path lengths of the sub-waveguides of the respective parameters of each waveguide are uniform. In order to ensure that the widths of any two sub-waveguides in parallel arrangement in the same arrangement order in two adjacent waveguides are different except for the input sub-waveguide and the output sub-waveguide, the following relationship must be satisfied:

l ₅₀₀ +l _500-600 ＝l _500-600 +l ₆₀₀

l ₆₀₀ +l _600-500 ＝l _600-500 +l ₅₀₀

wherein: l (L) ₅₀₀ 、l ₆₀₀ 、l _500-600 And l _600-500 Respectively represent sub-waveguides W ₅₀₀ 、W ₆₀₀ 、T _500-600 And T _600-500 Is a length of (c). From the above two formulas, l ₅₀₀ ＝l ₆₀₀ . When the sub-waveguide W ₅₀₀ And W is ₆₀₀ When the lengths are equal, the widths of any two parallel sub-waveguides in the same arrangement sequence of two adjacent waveguides are different except for the input sub-waveguide and the output sub-waveguide.

In one embodiment provided by the application, as shown in fig. 2, the lengths of two adjacent waveguides are in an arithmetic progression, the geometric parameters of the 1 st sub-waveguide in the two adjacent waveguides are the same, the lengths of the K-th sub-waveguide are in an arithmetic progression, and the same geometric parameters of the 2 nd to K-1 th sub-waveguides are all different, wherein DeltaL is more than 0.

In this embodiment, it is preferable that the width parameters of any position between the 2 nd to the K-1 st sub-waveguides in the adjacent two waveguides are different.

In this embodiment, the preferred sub-waveguide includes a cylindrical sub-waveguide and a tapered sub-waveguide, the 1 st sub-waveguide and the k th sub-waveguide are both cylindrical sub-waveguides, and the width parameters of the 1 st sub-waveguide and the k th sub-waveguide are different; in the 2 nd to the K-1 th sub-waveguides, the cylindrical sub-waveguides and the tapered sub-waveguides are alternately connected in turn, and the width parameters of the end parts of the tapered sub-waveguides are consistent with those of the cylindrical waveguides connected with the tapered sub-waveguides.

Specifically, as shown in fig. 2, fig. 2 shows a straight waveguide array with equal optical paths, each waveguide is sequentially arranged at intervals along a first direction, each waveguide extends along a second direction, each waveguide has no bending area, the lengths of output sub-waveguides of each waveguide are arranged in an equal difference mode, so that the equal difference of the lengths of the waveguides is ensured, the equal difference of the optical paths of light output by each waveguide can be realized, and the waveguide array realizes non-zero specific optical path difference.

Specifically, the waveguide array shown in FIG. 2 comprises 3 waveguides, each waveguide comprising 6 sub-waveguides, the 6 sub-waveguides comprising 4 sub-waveguides of different widths, the 4 sub-waveguides comprising 2 sub-waveguides of different widths, the widths being set to 500nm and 600nm, respectively, using W ₅₀₀ And W is ₆₀₀ And (3) representing. Wherein 2 different width wavelets are connected by a tapered wavelet guide, respectively using T _500-600 And T _600-500 And (3) representing.

The widths of the input and output sub-waveguides of the 3 waveguides are 500nm, that is, the widths of the 1 st and k th sub-waveguides are 500nm. However, the lengths of the input sub-waveguides of the 3 waveguides are all equal, and the lengths of the output sub-waveguides of the 3 waveguides are set equally. Besides the input sub-waveguide and the output sub-waveguide, the widths of the sub-waveguides which are arranged in parallel and positioned in the same arrangement sequence are different in the two adjacent waveguides, so that the phase cannot be matched, the crosstalk between the sub-waveguides which are arranged in parallel and positioned in the same arrangement sequence can be effectively reduced, and the waveguide array can be arranged more tightly under the condition of the same crosstalk intensity.

Using L _in And L _out Representing the optical path length of the input and output sub-waveguides, respectively, L being used in addition to the input and output sub-waveguides ₅₀₀ And L ₆₀₀ Respectively represent sub-waveguides W ₅₀₀ And W is ₆₀₀ Uses L _500-600 And L _600-500 Respectively represent tapered sub-waveguides T _500-600 And T _600-500 Is provided). Thus, the total optical path length l=l of each waveguide _in +L ₅₀₀ +L ₆₀₀ +L _500-600 +L _600-500 +L _out . As long as the optical path length of the output sub-waveguide of the corresponding parameter of each waveguide is set equal difference, the total optical path length L of the 3 waveguides is set equal difference. In order to ensure that the widths of any two sub-waveguides in parallel arrangement in the same arrangement order in two adjacent waveguides are different except for the input sub-waveguide and the output sub-waveguide, the following relationship must be satisfied:

l ₅₀₀ +l _500-600 ＝l _500-600 +l ₆₀₀

l ₆₀₀ +l _600-500 ＝l _600-500 +l ₅₀₀

wherein: l (L) ₅₀₀ 、l ₆₀₀ 、l _500-600 And l _600-500 Respectively represent sub-waveguides W ₅₀₀ 、W ₆₀₀ 、T _500-600 And T _600-500 Is a length of (c). From the above two formulas, l ₅₀₀ ＝l ₆₀₀ . When the sub-waveguide W ₅₀₀ And W is ₆₀₀ When the lengths are equal, the widths of any two parallel sub-waveguides in the same arrangement sequence of two adjacent waveguides are different except for the input sub-waveguide and the output sub-waveguide.

As shown in fig. 3, in an embodiment of the present application, the waveguide includes at least a first waveguide segment and a second waveguide segment electrically connected to the first waveguide segment, and each of the first waveguide segment and the second waveguide segment includes K sub-waveguides. The lengths of the two adjacent waveguides are identical, in the two adjacent waveguides, the geometric parameters of the 1 st sub-waveguide of the first waveguide section are identical, the geometric parameters of the K sub-waveguide are identical, and the geometric parameters of the 1 st sub-waveguide of the second waveguide section are identical, and the geometric parameters of the K sub-waveguide are identical.

In the same waveguide, the geometric parameters of the Kth sub-waveguide of the first waveguide section and the 1 st sub-waveguide of the second waveguide section are the same, and the geometric parameters of the 1 st sub-waveguide of the first waveguide section and the Kth sub-waveguide of the second waveguide section are the same; in two adjacent waveguides, the same geometric parameters of the 2 nd to the K-1 th sub-waveguides in the first waveguide section are different, and the same geometric parameters of the 2 nd to the K-1 th sub-waveguides in the second waveguide section are different, wherein DeltaL=0.

In this embodiment, the width parameters of any position of the sub-waveguides are different from the 2 nd to the K-1 st sub-waveguides. In this embodiment, the geometric parameters of the 1 st sub-waveguide and the K th sub-waveguide of the first waveguide segment are the same or different.

In this embodiment, the 1 st sub-waveguide of the first waveguide section and the K th sub-waveguide of the second waveguide section are both cylindrical waveguides, the K th sub-waveguide of the first waveguide section and the 1 st sub-waveguide of the second waveguide section are both curved waveguides, the two curved waveguides are electrically connected through an electrical device, and the curved directions of the two curved waveguides are opposite.

Specifically, as shown in fig. 3, fig. 3 shows a bent waveguide array with equal optical paths, where each waveguide is sequentially arranged at intervals along a first direction, then each waveguide extends along a second direction, extends for a section, passes through a section of bent waveguide from the first direction, is connected with a certain electric device, passes through a section of bent waveguide from the first direction, and extends along the second direction.

The waveguide array comprises 3 waveguides, each waveguide comprises 12 sub-waveguides, and the 12 sub-waveguides comprise 2 waveguides with different widths, namely 500nm and 600nm, respectively using W ₅₀₀ And W is ₆₀₀ Representing that the 2 different width wavelets are connected by a tapered wavelet guide, respectively using T _500-600 And T _600-500 Indicating that a curved sub-waveguide R is used between an electrical device and a tapered sub-waveguide ₅₀₀ The width of the connection is 500nm. By w _nk The kth sub-waveguide representing the nth waveguideWidth then the sub-waveguide width distribution of this waveguide array can be represented by the following matrix:

thus, w ₁₁ ＝w ₂₁ ＝w ₃₁ ＝w _{1 12} ＝w _{2 12} ＝w _{3 12} ＝500nm，w ₁₆ ＝w ₁₇ ＝w ₂₆ ＝w ₂₇ ＝w ₃₆ ＝w ₃₇ =500 nm. Similarly, use l _nk Representing the length of the kth sub-waveguide of the nth waveguide, the sub-waveguide length distribution of this waveguide array can be represented by the following matrix:

in the present embodiment, l ₁₁ ＝l ₂₁ ＝l ₃₁ ，l _{1 12} ＝l _{2 12} ＝l _{3 12} ，l ₁₆ ＝l ₁₇ ＝l ₂₆ ＝l ₂₇ ＝l ₃₆ ＝l ₃₇ 。

By l _500-600 And l _600-500 Respectively represent tapered sub-waveguides T _500-600 And T _600-500 Is a length of (c). In this embodiment, l of 3 waveguides _500-600 Equal, l _600-500 And are also equal. Therefore, in order to ensure the uniform optical path length of the 3 waveguides, only the sub-waveguides W need to be satisfied ₅₀₀ Is equal and the sub-wavelength W is equal ₆₀₀ Is equal in total length. Namely:

l ₁₂ +l ₁₈ ＝l ₂₅ +l ₂₁₁ ＝l ₃₂ +l ₃₈

l ₁₄ +l _{1 10} ＝l ₂₃ +l _{2 9} ＝l ₃₄ +l _{3 10}

when the sub-waveguide W ₅₀₀ Length and wavelet guide W ₆₀₀ Is far longer than l _500-600 、l _600-500 And device spacing = d, the tapered wavelets may be ignoredThe lengths of the waveguides, the total lengths of the straight waveguides of the 3-segment waveguide extending in the second direction are approximately equal, in which case, in order to ensure that the sub-waveguide widths of most positions of the adjacent two waveguides are different except for the input sub-waveguide and the output sub-waveguide, the following relationship must be satisfied:

l ₁₂ ≈l ₂₃ ≈l ₃₂

l ₁₄ ≈l ₂₅ ≈l ₃₄

l ₁₈ ≈l ₂₉ ≈l ₃₈ ，

l _{1 10} ≈l _{2 11} ≈l _{3 10}

the following relationship can be deduced from the above two formulas:

l ₁₂ +l ₁₈ ≈l ₁₄ +l _{1 10}

l ₁₂ ≈l ₁₄

l ₁₈ ≈l _{1 10}

similarly, it can be deduced that the other two waveguides also have a similar relationship, i.e. sub-waveguide W ₅₀₀ Is the total length of (2) and the sub-waveguide W ₆₀₀ Equal in total length and extending in the second direction ₅₀₀ Is equal to the length of the sub-waveguide W ₆₀₀ Is a length of (c).

Therefore, the widths of most of the parallel sub-waveguides in the same arrangement sequence are different between the adjacent two waveguides except the input sub-waveguide and the output sub-waveguide, so that the phases of the sub-waveguides are difficult to match, the crosstalk between the sub-waveguides can be effectively reduced, and the waveguide arrays can be arranged more tightly under the condition of the same crosstalk intensity.

In one embodiment of the present application, the waveguide includes at least a first waveguide segment and a second waveguide segment electrically connected to the first waveguide segment, each of the first waveguide segment and the second waveguide segment includes K sub-waveguides; the lengths of the two adjacent waveguides are in an arithmetic progression, the geometric parameters of the 1 st sub-waveguide of the first waveguide section and the geometric parameters of the K sub-waveguide are the same, the geometric parameters of the 1 st sub-waveguide of the second waveguide section are the same, and the geometric parameters of the K sub-waveguide are in an arithmetic progression.

In the same waveguide, the geometric parameters of the K-th sub-waveguide of the first waveguide section and the 1-th sub-waveguide of the second waveguide section are the same; in the two adjacent waveguides, the same geometric parameters of the 2 nd to the K-1 th sub-waveguides in the first waveguide section are different, and the same geometric parameters of the 2 nd to the K-1 th sub-waveguides in the second waveguide section are different, wherein DeltaL is more than 0.

In this embodiment, the width parameters of any position of the sub-waveguides are different from the 2 nd to the K-1 st sub-waveguides. In this embodiment, the geometric parameters of the 1 st sub-waveguide and the K th sub-waveguide of the first waveguide segment are the same or different.

In this embodiment, the 1 st sub-waveguide of the first waveguide section and the K th sub-waveguide of the second waveguide section are both cylindrical waveguides, the K th sub-waveguide of the first waveguide section and the 1 st sub-waveguide of the second waveguide section are both curved waveguides, the two curved waveguides are electrically connected through an electrical device, and the curved directions of the two curved waveguides are opposite.

Unlike the embodiment shown in fig. 3, the waveguide array provided in this embodiment has equal lengths of the input sub-waveguides and equal lengths of the output sub-waveguides of the first waveguide segment of the 3 waveguides. The lengths of the input sub-waveguides of the second waveguide sections of the 3 waveguides are equal, and the lengths of the output sub-waveguides are arranged in an equal difference mode. Besides the input sub-waveguide and the output sub-waveguide, the widths of the sub-waveguides which are arranged in parallel and positioned in the same arrangement sequence are different in the two adjacent waveguides, so that the phase cannot be matched, the crosstalk between the sub-waveguides which are arranged in parallel and positioned in the same arrangement sequence can be effectively reduced, and the waveguide array can be arranged more tightly under the condition of the same crosstalk intensity.

The foregoing description of the preferred embodiments of the application is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the application.

Claims (12)

1. A waveguide array for an OPA lidar, characterized by:

the waveguide array comprises N waveguides which are sequentially arranged at intervals in parallel along a first direction, wherein N is more than or equal to 2, N is a positive integer, and the optical path differences delta L of the N waveguides are in an arithmetic progression, wherein delta L is more than or equal to 0;

each waveguide comprises K sub-waveguides, and in the same waveguide, the K sub-waveguides are sequentially connected along a second direction, wherein K is more than or equal to 2, and K is a positive integer; the K sub-waveguides at least comprise M sub-waveguides with the same geometric parameters and different parameters, wherein K is more than or equal to M, M and more than or equal to 2, and M is a positive integer; in the adjacent waveguides, the arrangement order of M sub-waveguides along the second direction is different;

wherein the geometric parameter is any one of the parameters of the height, width, sidewall inclination angle and cross-sectional shape of the sub-waveguide.

2. The waveguide array of claim 1, wherein:

the K sub-waveguides at least comprise M sub-waveguides with different width parameters.

3. The waveguide array of claim 1, wherein:

the lengths of two adjacent waveguides are identical, the geometric parameters of the 1 st sub-waveguide in the two adjacent waveguides are identical, the geometric parameters of the K-th sub-waveguide are identical, and the same geometric parameters of the 2 nd to K-1 th sub-waveguides are all different, wherein delta L=0; in the same waveguide, the geometric parameters of the 1 st sub-waveguide and the K th sub-waveguide are the same.

4. The waveguide array of claim 1, wherein:

the lengths of two adjacent waveguides are in an arithmetic series, the geometric parameters of the 1 st sub-waveguide in the two adjacent waveguides are the same, the lengths of the K-th sub-waveguide are in an arithmetic series, and the same geometric parameters of the 2 nd to K-1-th sub-waveguides are all different, wherein DeltaL is more than 0.

5. The waveguide array of claim 3 or 4, wherein:

the width parameters of any position of the 2 nd to the K-1 st waveguiding in the adjacent two waveguiding are different.

6. The waveguide array of claim 3 or 4, wherein:

the sub-waveguides comprise cylindrical sub-waveguides and conical sub-waveguides, and the 1 st sub-waveguide and the k th sub-waveguide are cylindrical sub-waveguides; in the sub-waveguides from the 2 nd to the K-1 th, the cylindrical sub-waveguides and the conical sub-waveguides are alternately connected in turn, and the width parameters of the end parts of the conical sub-waveguides are consistent with the width parameters of the cylindrical waveguides connected with the conical sub-waveguides.

7. The waveguide array of claim 1, wherein:

the waveguide at least comprises a first waveguide section and a second waveguide section electrically connected to the first waveguide section, and the first waveguide section and the second waveguide section both comprise the K sub-waveguides;

the lengths of two adjacent waveguides are identical, in the two adjacent waveguides, the geometric parameters of the 1 st sub-waveguide of the first waveguide section are identical, the geometric parameters of the K th sub-waveguide are identical, the geometric parameters of the 1 st sub-waveguide of the second waveguide section are identical, and the geometric parameters of the K th sub-waveguide are identical;

in the same waveguide, the geometric parameters of the Kth sub-waveguide of the first waveguide section and the 1 st sub-waveguide of the second waveguide section are the same, and the geometric parameters of the 1 st sub-waveguide of the first waveguide section and the Kth sub-waveguide of the second waveguide section are the same;

in two adjacent waveguides, the same geometric parameters of the 2 nd to the K-1 th sub-waveguides in the first waveguide section are different, and the same geometric parameters of the 2 nd to the K-1 th sub-waveguides in the second waveguide section are different, wherein DeltaL=0.

8. The waveguide array of claim 1, wherein:

the waveguide at least comprises a first waveguide section and a second waveguide section electrically connected to the first waveguide section, and the first waveguide section and the second waveguide section both comprise the K sub-waveguides;

the lengths of two adjacent waveguides are in an arithmetic progression, in the two adjacent waveguides, the geometric parameters of the 1 st sub-waveguide of the first waveguide section are the same, the geometric parameters of the K th sub-waveguide are the same, the geometric parameters of the 1 st sub-waveguide of the second waveguide section are the same, and the geometric parameters of the K th sub-waveguide are in an arithmetic progression;

in the same waveguide, the geometric parameters of the Kth waveguide of the first waveguide section and the 1 st waveguide of the second waveguide section are the same;

in two adjacent waveguides, the same geometric parameters of the 2 nd to the K-1 th sub-waveguides in the first waveguide section are different, and the same geometric parameters of the 2 nd to the K-1 th sub-waveguides in the second waveguide section are different, wherein DeltaL is more than 0.

9. The waveguide array of claim 7 or 8, wherein:

in the sub-waveguides from the 2 nd to the K-1 th, the width parameters of any position of the sub-waveguides are different.

10. The waveguide array of claim 7 or 8, wherein:

the geometric parameters of the 1 st said sub-waveguide and the K th said sub-waveguide of said first waveguide segment are the same or different.

11. The waveguide array of claim 10, wherein:

the 1 st sub-waveguide of the first waveguide section and the K th sub-waveguide of the second waveguide section are cylindrical waveguides, the K th sub-waveguide of the first waveguide section and the 1 st sub-waveguide of the second waveguide section are bent waveguides, the two bent waveguides are electrically connected through an electrical device, and the bending directions of the two bent waveguides are opposite.

12. The waveguide array of claim 7, wherein:

the sub-waveguides comprise cylindrical sub-waveguides, conical sub-waveguides and curved waveguides, the width parameters of the cylindrical sub-waveguides are different, the 1 st sub-waveguide of the first waveguide section and the K th sub-waveguide of the second waveguide section are cylindrical sub-waveguides, and the K th sub-waveguide of the first waveguide section and the 1 st sub-waveguide of the second waveguide section are curved sub-waveguides;

in the sub-waveguides from the 2 nd to the K-1 th, the cylindrical sub-waveguides and the conical sub-waveguides are alternately connected in turn, and the width parameters of the end parts of the conical sub-waveguides are consistent with the width dimensions of the cylindrical waveguides connected with the conical sub-waveguides; in adjacent ones of said waveguides, the total length of all said sub-waveguides of said first waveguide segment having identical parameter values in said 2 nd to K-1 th said sub-waveguides and said second waveguide segment having identical parameter values in said 2 nd to K-1 th said sub-waveguides.