A WAVELENGTH CONTROLLABLE ARRAYED WAVEGUIDE GRATING

Abstract

The present invention discloses a wavelength controllable arrayed waveguide grating, of which the dispersion equation of the arrayed waveguide grating is:

[00001]$n_s\left(\frac{d_1.Math.x_1}{f_1}-\frac{d.Math.x}{f}\right)+n_c\Delta L=m\lambda ,$

where, λ is the work wavelength of the arrayed waveguide grating; ΔL is the geometric length difference between the adjacent arrayed waveguides in the waveguide array; m is the multiple of the central wavelength; n_s is the effective refractive index of the free transmission region; n_c is the effective refractive index of the transmission waveguide; d_1 and d represent the distances between the arrayed waveguides in the first free transmission region and the second free transmission region, respectively; f_1 and f are focal lengths of the first slab waveguide and the second slab waveguide, respectively; x_ 1 and x represent the positions of the input waveguide and the output waveguide on the Rowland circle, respectively.

Claims

1. A wavelength controllable arrayed waveguide grating, characterized in that including a planar substrate; and the following structure disposed on the planar substrate: at least one input waveguide for inputting optical signal; a first free transmission region, composed of a first slab waveguide and coupled with the output end of the input waveguide; a waveguide array, coupled with the output end of the first free transmission region; a second free transmission region, composed of a second slab waveguide and coupled with the output end of the waveguide array; at least one output waveguide for outputting optical signal, coupled with the output end of the second free transmission region; the dispersion equation of the arrayed waveguide grating is shown as follows: $n_s\left(\frac{d_1.Math.x_1}{f_1}-\frac{d.Math.x}{f}\right)+n_c\Delta L=m\lambda$ where, λ is the work wavelength of the arrayed waveguide grating; ΔL is the geometric length difference between the adjacent arrayed waveguides in the waveguide array; m is the multiple of the central wavelength; n.sub.s is the effective refractive index of the free transmission region; n.sub.c is the effective refractive index of the transmission waveguide; d.sub.1 and d represent the distances between the arrayed waveguides in the first free transmission region and the second free transmission region, respectively; f.sub.1 and f are focal lengths of the first slab waveguide and the second slab waveguide, respectively; x.sub.1 and x represent the positions of the input waveguide and the output waveguide on the Rowland circle, respectively.

2. The wavelength controllable arrayed waveguide grating to claim 1, characterized in that the arrayed waveguide grating is divided into a smaller first part and a larger second part by at least one divisional plane, and the divisional plane transversely passes through at least one of the first free transmission region and the second free transmission region.

3. The wavelength controllable arrayed waveguide grating to claim 2, characterized in that the angle between the divisional plane and the upper surface of the planar substrate is a right angle, an acute or an obtuse angle.

4. The wavelength controllable arrayed waveguide grating to claim 2, characterized in that the first part and the second part are connected by a fixed piece.

5. The wavelength controllable arrayed waveguide grating to claim 4, characterized in that the fixed piece is a fixed substrate.

6. The wavelength controllable arrayed waveguide grating to claim 2, characterized in that the first part and the second part are connected by an adhesive.

7. The wavelength controllable arrayed waveguide grating to claim 2, characterized in that the region of the divisional plane is filled with a refractive index matching curing agent.

8. The wavelength controllable arrayed waveguide grating to claim 2, characterized in that the first part can be replaced by an optical fiber waveguide.

9. The wavelength controllable arrayed waveguide grating to claim 1, characterized in that the waveguide array consists of a series of arrayed waveguides with geometric length increasing in arithmetic progression.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] FIG. 1 is a structural diagram depicting the wavelength controllable arrayed waveguide grating in embodiment 1 of the present invention, where, 101—input waveguide, 102—output waveguide, 103—first free transmission, 104—second free transmission, 105—waveguide array, 110—first part, 120—second part, 130—divisional plane, 140—planar substrate.

[0030] FIG. 2 is a structural diagram depicting the wavelength controllable arrayed waveguide grating in embodiment 2 of the present invention, where, 202—output waveguide, 203—first free transmission region, 204—second free transmission, 205—waveguide array, 210—optical fiber waveguide, 220—second part, 230—divisional plane, 240—planar substrate, 250—fixed substrate.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] Specific embodiments of the present invention are described in further detail in combination with the related drawings and embodiments below. However, in addition to the descriptions given below, the present invention can be applied to other embodiments, and the scope of the present invention is not limited by such, rather by the scope of the claims.

Embodiment 1

[0032] Referring to FIG. 1, which shows a wavelength controllable arrayed waveguide grating, including a planar substrate (140), and the following structure disposed on the planar substrate (140):

[0033] an input waveguide (101) for inputting optical signal;

[0034] a first free transmission region (103), composed of a first slab waveguide and coupled with the output end of the input waveguide (101);

[0035] a waveguide array (105), coupled with the output end of the first free transmission region (103);

[0036] a second free transmission region (104), composed of a second slab waveguide and coupled with the output end of the waveguide array (105);

[0037] at least one output waveguide (102) for outputting optical signal, coupled with the output end of the second free transmission region (104);

[0038] and the dispersion equation of the arrayed waveguide grating is shown as follows:

[00005]$n_s\left(\frac{d_1.Math.x_1}{f_1}-\frac{d.Math.x}{f}\right)+n_c\Delta L=m\lambda$

where, λ is the work wavelength of the arrayed waveguide grating; ΔL is the geometric length difference between the adjacent arrayed waveguides in the waveguide array; m is the multiple of the central wavelength; n.sub.s is the effective refractive index of the free transmission region; n.sub.c is the effective refractive index of the transmission waveguide; d.sub.1 and d represent the distances between the arrayed waveguides in the first free transmission region (103) and the second free transmission region (104), respectively; f.sub.1 and f are focal lengths of the first slab waveguide and the second slab waveguide, respectively; x.sub.1 and x represent the position of the input waveguide (101) and the output waveguide (102) on the Rowland circle, respectively. According to the application requirements, the geometric structure: d.sub.1, d, f.sub.1, f, ΔL, and effective refractive index: n.sub.c, n.sub.s can be determined.

[0039] In this embodiment, the arrayed waveguide grating is divided into a smaller first part (110) and a larger second part (120) by a divisional plane (130). The divisional plane (130) transversely passes through the first free transmission region (103), and is perpendicular to the upper surface of the planar substrate (140), or inclined to the upper surface of the planar substrate (140) with an angle (i.e., perpendicular to the central axis of the first free transmission region (103) or inclined with an angle to the central axis of the first free transmission zone (103)).

[0040] In this embodiment, the first part (110) and the second part (120) are connected by an adhesive. During the process of assembly, the working central wavelength of the arrayed waveguide grating λ is determined first; and then, according to the application requirements, the geometric structures: d.sub.1, d, f.sub.1, f, ΔL and effective refractive index of the waveguide: n.sub.c, n.sub.s are determined; next, adjust the relative position of the first part (110) and the second part (120) through the coupling monitoring, for example, the first part (110) moves relative to the second part (120) along the direction of divisional line, and the position of the input waveguide (101) or output waveguide (102) on the Rowland circle (i.e. x.sub.1 and x) changes at this time, so as to compensate for the working wavelength (i.e. λ) of the arrayed waveguide grating according to the dispersion equation of the arrayed waveguide grating; after adjusting the position, an adhesive is used to fix the two parts into a complete overall structure, and to ensure that there is no relative displacement between the two parts.

[0041] In this embodiment, the region of the divisional plane (130) is filled with a refractive index matching curing agent.

[0042] In this embodiment, the waveguide array (105) consists of a series of arrayed waveguides with geometric length increasing in arithmetic progression.

Embodiment 2

[0043] Referring to FIG. 2, which shows a wavelength controllable arrayed waveguide grating device, including a planar substrate (240), and the following structure disposed on the planar substrate (240):

[0044] an input waveguide (not marked in FIG. 2) for inputting optical signal;

[0045] a first free transmission region (203), composed of a first slab waveguide and coupled with the output end of the input waveguide;

[0046] a waveguide array (205), coupled with the output end of the first free transmission region (203);

[0047] a second free transmission region (204), composed of a second slab waveguide and coupled with the output end of the waveguide array (205);

[0048] at least one output waveguide (202) for outputting optical signal, coupled with the output end of the second free transmission region (204);

[0049] and the dispersion equation of the arrayed waveguide grating is shown as follows:

[00006]$n_s\left(\frac{d_1.Math.x_1}{f_1}-\frac{d.Math.x}{f}\right)+n_c\Delta L=m\lambda$

where, λ is the work wavelength of the arrayed waveguide grating; ΔL is the geometric length difference between the adjacent arrayed waveguides in the waveguide array; m is the multiple of the central wavelength; n.sub.s is the effective refractive index of the free transmission region; n.sub.c, is the effective refractive index of the transmission waveguide; d.sub.1 and d represent the distances between the arrayed waveguides in the first free transmission region (203) and the second free transmission region (204), respectively; f.sub.1 and f are focal lengths of the first slab waveguide and the second slab waveguide, respectively; x.sub.1 and x represent the position of the input waveguide (201) and the output waveguide (202) on the Rowland circle, respectively. According to the application requirements, the geometric structure: d.sub.1, d, f.sub.1, f, ΔL, and effective refractive index: n.sub.c, n.sub.s can be determined.

[0050] In this embodiment, the arrayed waveguide grating is divided into a smaller first part (not marked in FIG. 2) and a larger second part (220) by a divisional plane (230). The divisional plane (230) transversely passes through the first free transmission region (203), and is perpendicular to the upper surface of the planar substrate (240), or inclined to the upper surface of the planar substrate (240) with an angle (i.e., perpendicular to the central axis of the first free transmission region (203) or inclined with an angle to the central axis of the first free transmission zone (203)).

[0051] In this embodiment, the first part (i.e., the input waveguide which has been divided) is replaced by an external optical fiber waveguide (210).

[0052] In this embodiment, the optical fiber waveguide (210) and the second part (120) are connected through a fixed piece, such as fixed substrate (250). During the process of assembly, the working central wavelength of the arrayed waveguide grating A. is determined first; and then, according to the application requirements, the geometric structures: d.sub.1, d, f.sub.1, f, ΔL and effective refractive index of the waveguide: n.sub.s are determined; next, adjust the relative position of the optical fiber waveguide (210) and the second part (220) through the coupling monitoring, for example, the optical fiber waveguide (210) moves relative to the second part (220) along the direction of divisional line, and the position of the optical fiber waveguide (210) or output waveguide (202) on the Rowland circle (i.e. x.sub.1 and x) changes at this time, so as to compensate for the working wavelength (i.e. λ) of the arrayed waveguide grating according to the dispersion equation of the arrayed waveguide grating; after adjusting the position, assembling the optical fiber waveguide (210) and the second part (220) on the fixed substrate (250), respectively, so as to fix the two parts into a complete overall structure, and to ensure that there is no relative displacement between the two parts.

[0053] In this embodiment, the region of the divisional plane (230) is filled with a refractive index matching curing agent.

[0054] In this embodiment, the waveguide array (205) consists of a series of arrayed waveguides with geometric length increasing in arithmetic progression.

[0055] Moreover, in other embodiments, the divisional plane can also transversely pass through the second free transmission region, and is perpendicular to the upper surface of the planar substrate, or inclined to the upper surface of the planar substrate with an angle, and the smaller first part is part of the output waveguide which has been divided. The same technical effect can be achieved by adjusting the relative position of the first part and the second part (i.e., x.sub.1 and x) according to the dispersion equation of the arrayed waveguide grating, so as to compensate for the working wavelength (i.e. λ) of the arrayed waveguide grating, and finally, fixing the two parts by adhesive or fixed piece. At the same time, the smaller first part can still be replaced by external units to enhance its technical effect, such as an optical fiber waveguide.

[0056] The technical scheme of the present invention overcomes a problem of wavelength shift caused by the process parameters in the manufacturing process of arrayed waveguide grating chips, and proposes a design structure of arrayed waveguide grating, which compensates for the central wavelength shift caused by the deviation of process and design through adjusting the position of the input waveguide and output waveguide. The arrayed waveguide grating in the resent invention has a simple structure and is easy to implement, which can also accurately regulate the wavelength.

[0057] The technical features of the above embodiments can be combined arbitrarily, in order to make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction between the combination of these technical features, they shall be considered to be within the scope of this specification.

[0058] The present invention only described several above embodiments, which are described more specific and detailed, but it cannot be understood as a limitation on the scope of the present invention. It should be pointed out that for ordinary technical personnel in the art, without departing from the concept of the present invention, a number of deformation and improvements can be made, which belong to the scope of the present invention. Therefore, the scope of the present invention shall be subject to the recorded claims.