JP2001051138A - Temperature-independent optical multiplexer / demultiplexer - Google Patents

Abstract

(57) [PROBLEMS] To provide a temperature-independent optical multiplexer / demultiplexer capable of reducing additional loss and deterioration of crosstalk. SOLUTION: A channel waveguide array 3 provided with a plurality of channel waveguides having different lengths from each other is provided on a substrate 1, and an input side fan-shaped slab waveguide 5 is coupled to an input end thereof. An output-side fan-shaped slab waveguide 6 is coupled to the output end. A wedge-shaped optical resin member 12 using a silicon-based or epoxy-based optical resin is embedded in the input-side fan-shaped slab waveguide 5. The optical resin member 12 has a refractive index characteristic for compensating a change in the refractive index due to a temperature change of the channel waveguide array 3.
The inclination change does not occur on the equal phase plane at the output end of the device regardless of the temperature change.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature-independent optical multiplexer / demultiplexer, and more particularly to a temperature-independent optical multiplexer / demultiplexer using a channel waveguide array having a plurality of channel waveguides each having a core made of silica glass and having different lengths. The present invention relates to an optical multiplexer / demultiplexer.

[0002]

2. Description of the Related Art FIG. 7 shows an arrayed waveguide grating (g).
This shows a conventional optical multiplexer / demultiplexer using (rating). FIG.
Shows an aa 'cross section of FIG. On a quartz substrate 1, a plurality of cores (co) made of quartz glass having a square cross-sectional shape are provided.
re) 2 is formed in a predetermined pattern to form a channel waveguide array 3, and a cladding 4 made of pure silica glass is provided so as to cover the channel waveguide array 3. I have.
Titanium oxide (TiO ₂ ) is added to the core 2.
A channel waveguide is formed by the core 2 and the cladding 4,
Here, 22 are provided. As shown in FIG. 7, the 22 channel waveguides of the channel waveguide array 3 are set to different lengths from each other, and are set to be longer toward the outside (bulging side).

[0003] At both ends of the channel waveguide array 3, an input-side fan-shaped slab waveguide 5 (input waveguide) and an output-side fan-shaped slab waveguide 6 (output waveguide) are connected. One input channel waveguide 7 is connected to the input-side fan-shaped slab waveguide 5, and a plurality of output channel waveguides 8-1 to 8-8 are connected to the output-side fan-shaped slab waveguide 6. I have.

[0004] In the above configuration, the light including various wavelengths input to the input channel waveguide 7 is input to each of the cores 2 of the channel waveguide array 3 by the input side fan-shaped slab waveguide 5. When the light input to the channel waveguide array 3 propagates through each of the cores 2 and reaches the output-side fan-shaped slab waveguide 6, the equiphase plane is inclined depending on the wavelength. At the connection surface between the waveguide 6 and the output channel waveguides 8-1 to 8-8, the light focusing position shifts. For this reason, the output light from the output-side fan-shaped slab waveguide 6 is selectively output to the output channel waveguides 8-1 to 8-n according to the shift state of the equal phase plane, and is output from the eight waveguides. Output light of different wavelengths.

In the channel waveguide array 3, when the temperature changes, the length L of the channel waveguide changes due to thermal expansion, and the refractive index of the quartz glass constituting the core 2 changes due to the thermo-optic effect. . Therefore, the equiphase plane 9 at 0 ° C. shown in FIG. 7 changes to the position of the equiphase plane 10 at 60 ° C., for example. As a result, the light condensing position shifts according to the temperature change, and the wavelength to be demultiplexed changes.

FIG. 9 shows the details of the connection between the channel waveguide array 3 and the output fan-shaped slab waveguide 6. In the figure, d is the pitch of the channel waveguides of the channel waveguide array 3, and θ is the emission angle. Now, focusing on a certain wavelength, the following equation must be satisfied in order for the equiphase surfaces shown in FIG. 7 to be continuous. (2π / λ) N _eff · ΔL + (2π / λ) n _S dsin θ = 2πm (1) (where λ is the wavelength, m is the diffraction order (m = 1, 2, 3,
...), _ΔL is the waveguide length difference of the channel waveguide array 3, N _eff is the equivalent refractive index of the channel waveguide array 3, n
_S is the equivalent refractive index of the output fan-shaped slab waveguide 6, and ΔL is the waveguide length difference of the channel waveguide array 3. )

Since the equivalent refractive index N _eff , n _S is substantially equal to the refractive index n of the quartz glass of the core 2 constituting the channel waveguide array 3, it is approximated as n = _eff = n _S and the temperature is T T Then, the angle change Δθ of the light beam when the temperature changes by ΔT (the change in the equiphase plane) is given by the following equation based on the above equation (1). Δθ / ΔT = (1 / n) × (Δn / ΔT) × ΔL / d (2)

Here, Δn / ΔT is a change in the refractive index of the waveguide, and the effect of the linear expansion due to the temperature change is smaller than the change in the refractive index, and is ignored here. The above (2)
By using the equation, the change of the demultiplexing wavelength with respect to the temperature change is given by the following equation. Δλ / ΔT = (λ × n × d / n △ L) × (△ θ / △ T) = (λ / n) × (∂n / ∂T) (3) For example, titanium oxide ( {Λ / ΔT in quartz glass doped with TiO ₂ ) is n ≒ 1.45 and {n / ∂T}.
When 1 × 10 ⁻⁵ and λ = 1550 nm, 0.01 (nm
/ ° C). An optical component using such a channel waveguide array 3 is generally used under a temperature environment of 0 to 60 ° C.

From the above results, the temperature change is from 0 ° C. to 60 ° C.
In the case of ° C., the shift of the demultiplexing wavelength is 0.6 nm at the maximum, and therefore cannot be used in a practical system. In order to reduce the change of the center wavelength due to the temperature, conventionally, a configuration has been proposed in which a wedge-shaped groove is provided in a part of the channel waveguide array 3 and an optical resin member is inserted therein. Hereinafter, this configuration will be described.

FIG. 10 shows another conventional optical multiplexer / demultiplexer in which an optical resin member is partially interposed in a wedge shape. In order to reduce the change in the center wavelength due to temperature, the value according to the above equation (2) must be smaller than the value according to the above equation (3). Therefore, as shown in FIG. 10, a wedge-shaped groove having a maximum width W is provided in a part of the channel waveguide array 3, and the optical resin member 11 is inserted therein. This cancels the shift of the demultiplexing wavelength of the equiphase plane with respect to the temperature. The condition in this case is given by the following equation using the above equation (2).

(∂n / ∂T) △ L + (△ L '× ∂n' / ∂T) = 0 (4) Here, △ L 'is a difference between groove widths in each channel waveguide array. The values sequentially differ from those of the adjacent channel waveguides by this length. n ′ is the refractive index of the optical resin, ∂
n ′ / ΔT is a change in the refractive index temperature of the optical resin. For example, when a silicon-based resin is used for the optical resin member 11, ∂n '/ ∂T is as follows. ∂n '/ ∂T ≒ -37 × 10 ^{-5 Since} the refractive index temperature change of the quartz glass is ∂n / ∂T ≒ 1 × 10 ^-5 , △ L' / △ L is as follows. ΔL ′ / ΔL = 1/37 (5)

Generally, the waveguide length difference ΔL is about 100 μm, so that the groove width difference ΔL ′ is about 2 μm. However, the number of waveguides in the channel waveguide array 3 is 10
Since the number is about 0 to 200, the maximum width W of the optical resin member 11 is a large value of 400 μm.

[0013]

However, according to the conventional optical multiplexer / demultiplexer, in a configuration having several hundreds of waveguides, the maximum width W of the wedge-shaped groove reaches several hundred μm, so that diffraction loss is reduced. Increased, and a large additional loss of about 4 to 6 dB has been generated.

Further, in order to obtain good demultiplexing characteristics with small crosstalk, generally a high-precision groove width whose width is smoothly changed to sub-μm or less is required. When trying to form a groove, it is difficult to increase the processing accuracy, resulting in degradation of crosstalk.

Accordingly, it is an object of the present invention to provide a temperature-independent optical multiplexer / demultiplexer capable of reducing the additional loss and the deterioration of crosstalk.

[0016]

In order to achieve the above object, the present invention has, as a first feature, a substrate, an input channel waveguide formed on one side of the substrate, and one end of the substrate. An input fan-shaped slab waveguide connected to the other end of the input channel waveguide, and a plurality of ones connected to the other end of the input fan-shaped slab waveguide and sequentially elongated by a desired waveguide length difference. A channel waveguide array including a channel waveguide, an output fan-shaped slab waveguide having one end connected to the other end of the channel waveguide array, and a plurality of output fan-shaped slab waveguides connected to the other end of the output fan slab waveguide. The input-side fan-shaped slab waveguide or the output-side fan-shaped slab waveguide has a sign of a refractive index temperature change opposite to that of the plurality of channel waveguides. In the optical path To provide a temperature insensitive optical demultiplexer, wherein.

According to this configuration, the temperature compensation member provided in the optical path of the input-side fan-shaped slab waveguide or the output-side fan-shaped slab waveguide has a refractive index temperature change reverse to that of the plurality of channel waveguides. Because of the sign, even if a change in the refractive index of the channel waveguide array occurs due to a change in ambient temperature or the like, the temperature compensation member functions to cancel the change in the refractive index temperature of the channel waveguide array. Therefore, the equal phase plane of the output light of the channel waveguide array does not change regardless of the temperature change of the installation atmosphere. By providing the temperature compensating member on the input-side fan-shaped slab waveguide or the output-side fan-shaped slab waveguide, the thickness can be made thinner than when the temperature compensating member is provided on the channel waveguide array. As a result, it is possible to reduce additional loss and crosstalk.

In order to achieve the above object, the present invention provides, as a second feature, a substrate, an input channel waveguide formed on one side of the substrate, and one end of the input channel waveguide. An input-side fan-shaped slab waveguide connected to the end,
A channel waveguide array having a plurality of channel waveguides having one end connected to the other end of the input-side fan-shaped slab waveguide and being sequentially elongated by a desired waveguide length difference; An output-side fan-shaped slab waveguide connected to one end and a plurality of output channel waveguides connected to the other end of the output-side fan-shaped slab waveguide, wherein the input-side fan-shaped slab waveguide or the output is provided. Provided is a temperature-independent optical multiplexer / demultiplexer, wherein a wedge-shaped multi-component glass member is provided in an optical path of a side fan type slab waveguide.

According to a third aspect of the present invention, a substrate, an input channel waveguide formed on one side of the substrate, and one end of the input channel waveguide are provided. And an input-side fan-shaped slab waveguide connected to the other end of the input-side fan-shaped slab waveguide; A channel waveguide array, an output sector slab waveguide having one end connected to the other end of the channel waveguide array, and a plurality of output channel conductors connected to the other end of the output sector slab waveguide. A temperature-independent optical multiplexer / demultiplexer comprising a waveguide, wherein a wedge-shaped optical resin member is provided in an optical path of the input-side fan-shaped slab waveguide or the output-side fan-shaped slab waveguide. I will provide a.

According to the second and third aspects of the present invention, a wedge-shaped multi-component glass member or an optical resin provided in the optical path of the input-side fan-shaped slab waveguide or the output-side fan-shaped slab waveguide. The member acts so that its refractive index cancels the change in the refractive index of the channel waveguide array due to the temperature, and the angle change in the phase plane of the output light of the channel waveguide array is independent of the temperature change of the installation atmosphere. Will not occur. Further, by providing the optical resin member on the input-side fan-shaped slab waveguide or the output-side fan-shaped slab waveguide, the thickness can be reduced, so that the additional loss and the crosstalk can be reduced.

[0021]

FIG. 1 shows a temperature-independent optical multiplexer / demultiplexer according to a first embodiment of the present invention. On the substrate 1 using quartz glass or silicon, FIG.
The channel waveguide array 3 having the cross-sectional shape shown in FIG. An input-side fan-shaped slab waveguide 5 (input waveguide) and an output-side fan-shaped slab waveguide 6 (output waveguide) are connected to both ends of the channel waveguide array 3. One input channel waveguide 7 is connected to the input-side fan-shaped slab waveguide 5, and a plurality of output channel waveguides 8-1 to 8-8 are connected to the output-side fan-shaped slab waveguide 6. I have. A wedge-shaped optical resin member 12 using a silicon-based or epoxy-based optical resin is provided as a temperature compensation member in the middle of the input-side fan-shaped slab waveguide 5. The optical resin member 12 moves the position on the wide side to the channel waveguide array 3.
Is determined by the sign of the temperature change of the refractive index of the quartz glass used for the core 2. In FIG. 1, the signs of the refractive index temperature changes of the optical resin member 12 and the quartz glass are opposite to each other.
Is set outside the channel waveguide array 3.

FIG. 2 shows the operation principle of the optical resin member 12 shown in FIG. In the figure, the solid line shows the isophase surface at 0 ° C., and the broken line shows the isophase surface at 60 ° C. Light that has entered the input-side fan-shaped slab waveguide 5 from the input channel waveguide 7 propagates through the input-side fan-shaped slab waveguide 5 and reaches an optical resin member 12 provided in the middle. At this time, the equi-phase plane of the input-side fan-shaped slab waveguide 5 on the incident side of the optical resin member 12 is the same at both the 0 ° C. equi-phase plane 14 and the 60 ° C. equi-phase plane 15. On the other hand, the equal phase surfaces 15 and 16 in the input side fan-shaped slab waveguide 5 on the emission side of the optical resin member 12 are set so as not to change the positions of the equal phase surfaces 9 and 10 in FIG. As described above, since the change in the refractive index temperature of the optical resin member 12 is opposite to the change in the refractive index temperature of the waveguides of the input-side fan-shaped slab waveguide 5 and the channel waveguide array 3, even if there is a temperature change. A temperature-independent optical multiplexer / demultiplexer can be obtained.

The light that has passed through the optical resin member 12 enters the channel waveguide array 3 and passes through each core. The equiphase plane at the exit of the channel waveguide array 3 is constant even if the temperature changes. That is, even if the ambient temperature changes, the light condensing position of each core of the channel waveguide array 3 does not shift, and the wavelength to be demultiplexed does not change. Hereinafter, the results of quantitative studies performed on the optical multiplexer / demultiplexer of the present invention will be described.

In FIG. 2, the angle of the optical resin member 12 is α, and the angle of the wavefront of the light after passing through the optical resin member 12 is θ. Since the optical resin member 12 has a refractive index n ′ different from the refractive index n of the quartz glass of the channel waveguide array 3, the angles of the equiphase surfaces 15 and 16 change.
The value θ is given by the following equation. Where θ≪1,
α≪1. θ = α (n′−n) / n ′ (6) When this is differentiated by the temperature T, as shown in the following equation,
The change of the angle θ of the equiphase plane with respect to the temperature is obtained. Δθ / ΔT = α (1 / n ′) × (∂n ′ / T) (7) where {n / {T} 1 × 10 ⁻⁵ and {n ′ / {T}}.
Since −37 × 10 ⁻⁵ , (∂n ′ / ∂T) ≫∂n /
∂T and n ′ ≒ n. From the above equation (2), the change Δθ / ΔT of the angle of the equiphase plane with respect to the temperature in the channel waveguide array 3 is 4 × 10 ⁻⁵ . Where ΔL =
120 μm, n = 1.45, ∂n / ∂T ≒ 1 × 10 ^-5 ,
d = 120 μm.

From the above equation (7), the angle α of the optical resin member 12 can be calculated by using {n ′ / {T} −37 × 10 ^−5.
= 0.15 (rad). At this time, assuming that the length of the optical resin member 12 is H, when the length H is 60 μm, the width W of the optical resin member 12 is 9 μm, which is the conventional value of 400 μm.
It is much smaller than μm.

FIG. 3 shows the relationship between the groove width and the loss in the channel waveguide. As is clear from FIG. 3, the loss increases exponentially with respect to the groove width. Therefore, when the groove width is reduced as in the present invention, the loss can be significantly reduced. Furthermore, in the input-side fan-shaped slab waveguide 5 on which the optical resin member 12 is formed, the optical confinement effect is only in the thickness direction of the waveguide and there is no lateral confinement effect. Even if the light is diffracted to some extent by 12, only light power radiated to the cladding in the vertical direction is lost. Therefore, the loss in the thickness direction can be reduced to 0.2 dB or less, and the loss can be significantly reduced as compared with the related art.

[Second Embodiment] FIG. 4 shows a temperature-independent optical multiplexer / demultiplexer according to a second embodiment of the present invention. In the configuration of FIG. 4, instead of the optical resin member 12 shown in FIG. 1, the input-side fan-shaped slab waveguide 5 is divided into two slab waveguides 5A and 5B, and a slit is formed therebetween. An optical resin member 17 is provided in the slit. As the optical resin member 17, a silicon-based or epoxy-based optical resin is used.
Also in this case, whether the maximum width of the optical resin member 17 is inside or outside the channel waveguide array 3 may be determined in the same manner as in the case of the optical resin member 12.

[Third Embodiment] FIG. 5 shows a third embodiment of a temperature-independent optical multiplexer / demultiplexer according to the present invention. The configuration of FIG. 5 has a configuration in which a multi-component glass member 18 made of multi-component glass is provided as a temperature compensation member instead of the optical resin member 17 shown in FIG. The multi-component glass member 18 is fixed in the slit 17 using an optical adhesive. The multi-component glass member 21 has a refractive index of n ′ ≒ 1.55 and a temperature coefficient of {n ′ / {T} −10 × 10 ⁻⁵ ”. The wide side of the multi-component glass member 18 is fixed so as to be outside (swelling side) of the channel waveguide array 3. It is determined by the temperature change characteristics of the refractive index of the quartz glass of the waveguide array 3. In the case of the present invention, the waveguide of the channel waveguide array 3 and the multi-component glass member 18 are used.
Are different from each other, the wide side of the multi-component glass member 18 is outside the channel waveguide array 3. The overall operation principle in the configuration of FIG.
As described above, the overlapping description is omitted here.

The change in the angle of the equal phase plane Δθ / ΔT is 4 × 1
0 ^-5 , ΔL = 120 μm, n = 1.45, {n / {T}}
When 1 × 10 ⁻⁵ and d = 120 μm, the angle α of the multi-component glass member 18 is {n ′ / {T} from the above equation (7).
When −10 × 10 ⁻⁵ is used, α = 0.36 (rad). At this time, assuming that the length of the multi-component glass member 18 is H, when H is 60 μm, the maximum width W of the multi-component glass member 18 is 33 μm, which can be greatly reduced from the conventional value of 400 μm.

As shown in FIG. 3, the loss of the channel waveguide increases exponentially with respect to the groove width of the multi-component glass member 18 due to light diffraction. For this reason, the present invention, which can reduce the occupied volume of the multi-component glass member 18,
Loss can be greatly reduced. Furthermore, in the input-side fan-shaped slab waveguide 5 to which the multi-component glass member 18 is fixed, light is confined only in the thickness direction of the waveguide, and there is no confinement in the lateral direction. Even if the light is diffracted to some extent in the component glass member 18, only the light power radiated to the cladding in the vertical direction is lost. As a result, according to the third embodiment of the present invention,
There is an advantage that the loss can be reduced to 0.5 dB or less.

FIG. 6 shows a wavelength-loss characteristic of a temperature-independent optical multiplexer / demultiplexer according to a third embodiment of the present invention.
(A) is a wavelength loss characteristic when the multi-component glass member 18 is provided, and (b) is a wavelength loss characteristic when the multi-component glass member 18 is not provided. As is clear from FIG. 6A, it is understood that the use of the multi-component glass member 18 makes the temperature change of the demultiplexing wavelength extremely small. Further, no change in the loss in the pass band as shown in FIG. 6B is observed, and it is understood that low loss is realized. Further, unlike the conventional configuration, it is not necessary to form a groove over a wide area, and the surface can be processed with high precision of 0.01 μm or less by polishing or the like, so that crosstalk is not deteriorated.

In each of the above embodiments, the optical resin members 12 and 17 and the multi-component glass member 18 are all provided in the input-side fan-shaped slab waveguide 5, but instead the output-side fan-shaped slab waveguide 5 is used. It can also be provided on the mold slab waveguide 6 side.

In order to dispose the optical resin member 17 and the multi-component glass member 18, the input side fan-shaped slab waveguide 5 is
Although the slit is formed by division, the present invention is not limited to this. For example, a structure in which a groove is formed by laser processing or the like may be used.

[0034]

As described above, according to the temperature-independent optical multiplexer / demultiplexer of the present invention, the temperature compensating member having the sign of the temperature change of the refractive index opposite to that of the plurality of channel waveguides is connected to the input side or the output side. Since it is provided in the optical path of the fan-shaped slab waveguide on the side, the temperature compensating member functions to cancel the temperature change of the refractive index of the channel waveguide array. As a result, similarly to the case where the embedded member is provided in the channel waveguide array, it is possible to prevent an angle change in the equal phase plane of the output light of the channel waveguide array regardless of the temperature change of the installation atmosphere. it can. Since the temperature compensating member is provided in the input-side fan-shaped slab waveguide or the output-side fan-shaped slab waveguide, its thickness can be reduced, and additional loss and crosstalk can be reduced.

In addition, since the channel waveguide due to the temperature is provided with an optical resin member or a multi-component glass member for correcting an angle change of the equiphase plane of the ray in the input side fan type slab waveguide or the output side fan type slab waveguide, The size of the optical resin member or the multi-component glass member is smaller than that provided in the channel waveguide array, and the additional loss can be greatly reduced. Further, since it is not necessary to form a groove over a wide area as in the conventional case, the groove width can be controlled with high processing accuracy, and the deterioration of crosstalk can be greatly reduced.

[Brief description of the drawings]

FIG. 1 is a plan view showing a first embodiment of a temperature-independent optical multiplexer / demultiplexer according to the present invention.

FIG. 2 is an explanatory diagram showing an operation principle of the temperature-independent optical multiplexer / demultiplexer having the configuration of FIG.

FIG. 3 is a characteristic diagram showing a relationship between a groove width and a loss in a channel waveguide.

FIG. 4 is a plan view illustrating a temperature-independent optical multiplexer / demultiplexer according to a second embodiment of the present invention.

FIG. 5 is a plan view showing a temperature-independent optical multiplexer / demultiplexer according to a third embodiment of the present invention.

FIG. 6 shows wavelength-loss characteristics according to the third embodiment of the present invention.

FIG. 7 is a plan view showing a conventional optical multiplexer / demultiplexer using an arrayed waveguide grating.

FIG. 8 is a sectional view showing an a-a ′ section of FIG. 7;

9 is a partially enlarged view showing details of a connection portion between the channel waveguide array of FIG. 7 and an output fan-shaped slab waveguide.

FIG. 10 is a plan view showing another conventional optical multiplexer / demultiplexer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2 Core 3 Channel waveguide array 4 Cladding 5, 5A, 5B Input fan-shaped slab waveguide 6 Output fan-shaped slab waveguide 7 Input channel waveguide 8-1 to 8-8 Output channel waveguide 9, 13 , 150 ° C. Equi-phase surface 10, 14, 16 E 60 ° C. Equi-phase surface 12, 17 Optical resin member 18 Multi-component glass member

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Koichi Maru 5-1-1, Hidaka-cho, Hitachi City, Ibaraki Prefecture Within the Opto-System Research Laboratory, Hitachi Cable, Ltd. (72) Inventor Hideki Nanune Hidaka-cho, Hitachi City, Ibaraki Prefecture 5-1-1, Hitachi Cable, Ltd., Opto-System Research Laboratory (72) Inventor Tatsuo Teraoka 5-1-1, Hidaka-cho, Hitachi, Ibaraki Prefecture F-Term, Opto-System Research Laboratory, Hitachi Cable, Ltd. 2H047 KA02 KA04 KA12 KB10 LA01 LA19 QA04 QA05 QA07 TA00 TA35

Claims (10)

[Claims] A substrate; an input channel waveguide formed on one side of the substrate; an input fan-shaped slab waveguide having one end connected to the other end of the input channel waveguide; A channel waveguide array including a plurality of channel waveguides connected to the other end of the input-side fan-shaped slab waveguide and sequentially elongated by a desired waveguide length difference; one end being connected to the other end of the channel waveguide array; An output-side fan-shaped slab waveguide, comprising: a plurality of output channel waveguides connected to the other end of the output-side fan-shaped slab waveguide; and the input-side fan-shaped slab waveguide or the output-side fan. A temperature-independent optical multiplexer / demultiplexer, wherein the type slab waveguide has a temperature compensating member having a sign of a refractive index temperature change opposite to that of the plurality of channel waveguides in its optical path. 2. The method according to claim 1, wherein the plurality of channel waveguides are quartz glass having a positive temperature coefficient, and the temperature compensating member is a multi-component glass or an optical resin having a negative temperature coefficient. Item 2. A temperature-independent optical multiplexer / demultiplexer according to Item 1. 3. A substrate, an input channel waveguide formed on one side of the substrate, an input fan-shaped slab waveguide having one end connected to the other end of the input channel waveguide, and one end connected. A channel waveguide array including a plurality of channel waveguides connected to the other end of the input-side fan-shaped slab waveguide and sequentially elongated by a desired waveguide length difference, and one end is provided at the other end of the channel waveguide array. An output-side fan-shaped slab waveguide, and a plurality of output channel waveguides connected to the other end of the output-side fan-shaped slab waveguide; A temperature-independent optical multiplexer / demultiplexer, wherein a wedge-shaped multi-component glass member is provided in an optical path of a mold slab waveguide. 4. The wedge-shaped multi-component glass member is provided in a slit formed in the input-side fan-shaped slab waveguide or the output-side fan-shaped slab waveguide. A temperature-independent optical multiplexer / demultiplexer as described. 5. The wedge-shaped slit is formed by dividing the input-side fan-shaped slab waveguide or the output-side fan-shaped slab waveguide into two in the optical path direction. Temperature independent optical multiplexer / demultiplexer. 6. The temperature-independent optical coupling according to claim 3, wherein the wedge-shaped multi-component glass member is provided such that a wide side thereof is on a bulging side of the channel waveguide array. Duplexer. 7. The temperature-independent optical multiplexer / demultiplexer according to claim 3, wherein said substrate is made of quartz glass or silicon. 8. A substrate, an input channel waveguide formed on one side of the substrate, an input fan-shaped slab waveguide having one end connected to the other end of the input channel waveguide, and one end connected to the other end of the input channel waveguide. A channel waveguide array including a plurality of channel waveguides connected to the other end of the input-side fan-shaped slab waveguide and sequentially elongated by a desired waveguide length difference, and one end is provided at the other end of the channel waveguide array. An output-side fan-shaped slab waveguide, and a plurality of output channel waveguides connected to the other end of the output-side fan-shaped slab waveguide; A temperature-independent optical multiplexer / demultiplexer, wherein a wedge-shaped optical resin member is provided in an optical path of a mold slab waveguide. 9. The temperature-independent optical multiplexer / demultiplexer according to claim 8, wherein said optical resin member is made of silicon or epoxy. 10. The temperature-independent optical multiplexer / demultiplexer according to claim 8, wherein the optical resin member is provided such that a wide side thereof is on a bulging side of the channel waveguide array.