JP2003248116A - Multilayer film filter, its manufacturing method and its manufacturing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce a manufacturing cost by improving yield. <P>SOLUTION: A multilayer film filter is composed of a mirror block forming on substrates 1 and 2 two mirror layers 19 and 20 alternately laminating repeatedly plural times two dielectric layers 5 and 6, in which each optical thickness is equal to a quarter wavelength of a center wavelength and whose refractive indexes are different from each other, and a gap 10 which is a cavity layer by depositing the two mirror blocks opposite to the mirror layers 19 and 20. In this case, in order to set the center wavelength of the multilayer film filter, an interval between the two mirror layers 19 and 20 and a tilt angle of an optical axis of the multilayer film filter are adjusted to compose the gap 10. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multilayer filter, a method for manufacturing the same, and an apparatus for manufacturing the same, and more particularly, a multilayer filter which is a narrow band wavelength filter in an optical transmission system of a wavelength division multiplexing transmission system and the same. The present invention relates to a manufacturing method and a manufacturing apparatus thereof.

[0002]

2. Description of the Related Art In recent years, a wavelength division multiplexing transmission system (WDM: Waveleng) has been developed in order to increase the speed and bandwidth of an optical transmission system.
th Division Multiplexing) has been introduced. WDM
In the method, since the division multiplexing is performed at a wavelength interval of about 1 nm, a narrow band wavelength filter having good wavelength selectivity is required.

A dielectric multilayer film filter is known as such a narrow band wavelength filter. FIG. 1 shows the structure of a conventional multilayer filter. The multilayer filter includes a dielectric layer 5 having a refractive index n _H, a dielectric layer 6 having a refractive index n _L , and (n _H >
n _L ) are repeatedly laminated a plurality of times to form mirror layers 17 and 18
Cavity layer 11 having a refractive index of n _H , which is sandwiched between. The method for manufacturing the multilayer filter is as follows. The dielectric layers 5 and 6 are sequentially laminated on the substrate 1 to form the mirror layer 17, and the cavity layer 11 is formed on the mirror layer 17.
The dielectric layers 6 and 5 are sequentially laminated on the first layer 1 to form the mirror layer 18. The dielectric layers 5 and 6 are formed so that their optical thicknesses, that is, refractive index × thickness, are ¼ of the central wavelength, and the cavity layer 11 has an optical thickness at the center. The film is formed so as to have a half wavelength.

The multilayer filter thus formed is a narrow band filter centered on a specific center wavelength λ. FIG. 2 shows the transmittance characteristics of the conventional multilayer filter. It is a result of simulating the transmission characteristics of a single-cavity multilayer filter having only one cavity layer under ideal conditions. In this multilayer filter, the center wavelength is set to 1550 nm, the thickness of all the dielectric layers is λ / 4, and the thickness of the cavity layer is λ / 2. Therefore, it is a narrow band filter showing a high transmittance at a wavelength of 1550 nm.

FIG. 3 shows the transmittance characteristics of the conventional multilayer filter when there is an error. This is the same structure as the multilayer filter shown in FIG. 2 and the transmittance characteristics when there is an error in the film thickness of each layer. It can be seen that this multilayer filter has an error of about 1% in the film thickness of each layer, and therefore the center wavelength is shifted to the long wavelength side by about 9.8 nm.

A single cavity type multilayer film filter is
A multi-cavity type multilayer film filter in which a plurality of layers are stacked via a coupling layer is known. In the multi-cavity type multilayer filter, it is necessary to match the film thickness of more layers with high accuracy in order to obtain a desired wavelength selectivity.

The WDM system requires wavelength selectivity of about ± 0.1 nm for the center wavelength, depending on the specifications of the filter, and 0.01% accuracy for the film thickness of each layer. It Since the film thickness accuracy in the film forming method such as the conventional vapor deposition method is several%, the yield of the multilayer film filter is very low. Therefore, efforts are being made to increase the yield by making full use of optical or crystal type monitor devices.

[0008]

However, in the method of sequentially laminating the mirror layer and the cavity layer, the cavity layer cannot be formed last, and the film thickness cannot be controlled with high precision. The bandpass optical filter described in Japanese Patent Laid-Open No. 2000-321420 corrects the center wavelength by adjusting the film thickness of a coupling layer called an additional layer when stacking one-cavity type filters in layers. ing. However, in the correction of the film thickness of only the additional layer,
In some cases, the central wavelength cannot be corrected accurately, and there is a problem that the yield cannot be further improved.

That is, as described above, in the method of sequentially laminating all the layers on the substrate, it is difficult to match the center wavelengths with high precision, and it is possible to avoid a decrease in yield and an increase in manufacturing cost. Can not.

The present invention has been made in view of the above problems. An object of the present invention is to improve yield by forming one cavity layer with a gap.
It is an object of the present invention to provide a multilayer filter, a method for manufacturing the same, and a device for manufacturing the same, which reduce manufacturing cost.

[0011]

SUMMARY OF THE INVENTION In order to achieve such an object, the present invention according to claim 1 is characterized in that two dielectric layers having different refractive indexes are alternately laminated a plurality of times. A mirror layer, a mirror block formed on the substrate,
The two mirror blocks are provided with a gap serving as a cavity layer formed by facing the mirror layers.

According to a second aspect of the present invention, in the first aspect, the side end faces of the two mirror blocks are fixed by a fixed substrate to form the gap.

According to a third aspect of the present invention, in the first or second aspect, the gap is filled with an ultraviolet curable resin or a thermosetting resin to fix the two mirror blocks.

According to a fourth aspect of the present invention, in order to set the center wavelength of the multilayer filter according to the first, second or third aspect, the gap interval and the inclination angle of the optical axis of the multilayer filter are set. Is adjusted to form the gap.

The invention according to claim 5 has two mirror layers in which two dielectric layers having different refractive indices are alternately and repeatedly laminated a plurality of times, and a cavity layer sandwiched between the two mirror layers. In a multi-cavity type multi-layer film filter in which a plurality of multi-layer film filters are coupled via a coupling layer, one cavity layer is composed of a gap, and the other cavity layer is a dielectric layer.

According to a sixth aspect of the present invention, in the fifth aspect, one mirror layer forming the gap, or a filter block including the one mirror layer and a multilayer film filter, and the other mirror layer forming the gap. It is characterized in that each side end surface of a filter block including a mirror layer or the other mirror layer and a multilayer filter is fixed by a fixed substrate to form the gap.

According to a seventh aspect of the present invention, in the fifth or sixth aspect, the two gaps are fixed by filling the gap with an ultraviolet curable resin or a thermosetting resin.

According to an eighth aspect of the present invention, in order to set the center wavelength of the multi-cavity multilayer filter according to the fifth, sixth or seventh aspect, the gap interval and the multi-cavity multilayer filter are set. It is characterized in that the gap is formed by adjusting the inclination angle of the optical axis.

According to a ninth aspect of the present invention, two filter blocks each having a mirror layer, in which two dielectric layers having different refractive indexes are alternately and repeatedly laminated a plurality of times, are provided on the substrate. A method of manufacturing a multilayer film filter that forms a gap that becomes a layer, wherein one mirror layer that forms the gap or a filter block that includes the one mirror layer and the multilayer film filter is formed on a substrate, and The other mirror layer forming the gap or a filter block including the other mirror layer and a multilayer filter is formed on a substrate, the one mirror layer and the other mirror layer are opposed to each other, and the gap is formed. And a multi-layer film filter having one or more cavity layers.

According to a tenth aspect of the invention, in order to set the center wavelength of the multilayer filter according to the ninth aspect, the gap interval and the inclination angle of the optical axis of the multilayer filter are adjusted. And forming the gap.

The eleventh aspect of the present invention is characterized in that the center wavelength is set by measuring the transmittance characteristic of the multilayer filter according to the tenth aspect.

The invention according to claim 12 is the invention as defined in claims 9 and 1.
The two mirror layers described in 0 or 11 are formed by dividing one substrate on which the mirror layer is formed.

According to a thirteenth aspect of the present invention, in the apparatus for manufacturing a multilayer filter, two filter blocks each having a mirror layer formed by alternately laminating two dielectric layers having different refractive indexes a plurality of times on a substrate, The holding means for holding the mirror layers facing each other, the gap thickness adjusting means for changing the gap between the holding means to adjust the gap between the two mirror layers, and the inclination angle of the holding means Alternately, an inclination angle adjusting means for adjusting the inclination angle of the optical axis of the multilayer filter including the filter block and the gap, a measuring means for measuring the transmittance characteristic of the multilayer filter, and a measurement by the measuring means. Based on the transmittance characteristics, the gap thickness adjusting means adjusts the interval,
And a control unit for adjusting the tilt angle by the tilt angle adjusting unit to set the center wavelength of the multilayer filter.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 4 shows the structure of the multilayer filter according to the first embodiment of the present invention.
The multilayer filter is a single cavity type multilayer filter, and has a desired center wavelength of 1550 nm. The multilayer filter has a refractive index n _H, a dielectric layer 6 having a refractive index n _L , and (n _H > n _L ) sandwiched between mirror layers 19 and 20 that are repeatedly laminated a plurality of times. It has a gap 10 of rate n _G.

The method for manufacturing the multilayer filter is as follows.
Two mirror blocks each having the mirror layers 19 and 20 formed on the dielectric layers 5 and 6 each having an optical thickness equal to the quarter wavelength of the central wavelength are sequentially formed on the top. The mirror layers 19 and 20 of the two mirror blocks are opposed to each other to form the gap 10. The gap 10 is filled with, for example, vacuum, a gas such as air, or a liquid such as an ultraviolet curable resin. The thickness of the cavity layer, that is, the gap thickness, is configured so that the optical thickness is ½ of the center wavelength or an integral multiple thereof.

In the structure shown in FIG. 4, a multilayer filter may be used in which the dielectric layer 5 has a refractive index of n _L and the dielectric layer 6 has a refractive index of n _H. Further, it goes without saying that a multilayer filter in which the number of times of repeated lamination is changed may be used.

FIG. 5 shows the relationship between the gap thickness and the center wavelength of the multilayer filter according to the first embodiment of the present invention.
In the single-cavity type multilayer filter shown in FIG. 4, the mirror layers 19 and 20 are configured by repeatedly stacking 20 dielectric layers 5 and 6, and the gap 10 is filled with air. The film thickness accuracy of the dielectric layers 5 and 6 is about 1%, but since the relationship between the gap thickness and the center wavelength has a very good linearity, it can be understood that the desired center wavelength can be corrected by adjusting the gap thickness. .

FIG. 6 shows the transmittance characteristics of the multilayer filter according to the first embodiment of the present invention. In the multilayer filter shown in FIG. 5, the transmittance characteristics are shown when the gap 10 is filled with air and the gap thickness is 779.5 nm. The gap thickness for the central wavelength of 1550 nm is 775
However, since the thickness accuracy of the dielectric layers 5 and 6 is about 1%, the center wavelength can be set to 1550 nm by adjusting the gap thickness to 779.5 nm. Even when the film thickness accuracy of each dielectric layer forming the mirror layer is low, by adjusting the cavity layer by forming the gap, it is possible to manufacture a multilayer film filter with a desired center wavelength at a high yield and at low cost. it can.

FIG. 7 shows the structure of a multilayer filter according to the second embodiment of the present invention. The multilayer filter has a gap 10a sandwiched between mirror layers 19 and 20 formed on the substrates 1 and 2. Two mirror blocks composed of mirror layers 19 and 20 formed on the substrates 1 and 2 are fixed by fixed substrates 3 and 4, and a gap 1 made of air is formed.
0a is formed. With the fixed substrates 3 and 4, a vacuum,
Even when a gas such as air or a liquid such as an ultraviolet curable resin is filled in the gap, the thickness of the gap can be easily fixed. Further, it goes without saying that the multi-cavity multi-layer film filter described later can be similarly fixed by the fixed substrates 3 and 4.

FIG. 8 shows the structure of a multilayer filter according to the third embodiment of the present invention. The multilayer filter has a gap 10b sandwiched between mirror layers 19 and 20 formed on the substrates 1 and 2. The two mirror blocks composed of the mirror layers 19 and 20 formed on the substrates 1 and 2 are fixed by a gap 10b composed of an ultraviolet curable resin or a thermosetting resin. By filling the gap with such a resin, the two mirror blocks can be easily fixed. Further, it goes without saying that the multi-cavity multilayer filter to be described later can similarly be fixed with an ultraviolet curable resin or a thermosetting resin.

FIG. 9 shows the structure of a multilayer filter according to the fourth embodiment of the present invention. The fourth embodiment is a multi-cavity multilayer filter, and it is necessary that the center wavelengths of the respective multilayer filters each including a cavity layer and a mirror layer sandwiching the cavity layer exactly match the desired center wavelength. is there. One cavity layer is formed by a conventional film forming method, and the other cavity layer is formed by the gap shown in FIG. The first filter has a cavity layer 11 sandwiched between mirror layers 17 and 18 and having a refractive index n _H. The second filter is a mirror layer 19,
It has a gap 10 sandwiched between 20 and having a refractive index n _G.

The method of manufacturing a multi-cavity type multilayer filter is as follows.
7, the cavity layer 11 is formed on the mirror layer 17, and the dielectric layers are sequentially laminated on the cavity layer 11 to form the mirror layer 18. Further, after the coupling layer 8 is laminated, the dielectric layers are sequentially laminated to form the mirror layer 19 to manufacture the filter block. On the other hand, after the dielectric layers are sequentially laminated on the substrate 2 to form the mirror layer 20,
A mirror layer 19 of the filter block laminated on the substrate 1,
The gap 10 is formed by facing the mirror layer 20 laminated on the substrate 2. The gap 10 is filled with, for example, vacuum, a gas such as air, or a liquid such as an ultraviolet curable resin.

With this configuration, if the error in the center wavelength of the first filter is small, the center wavelength is adjusted by adjusting the gap thickness of the second filter. If the center wavelength of the first filter is longer than the desired center wavelength, the tilt angle of the multi-cavity multilayer filter with respect to the optical axis can be adjusted to change the center wavelength in the shorter direction.
That is, the center wavelength of the multi-cavity multilayer filter can be adjusted by adjusting the thickness of the gap 10 and the inclination angle of the multi-cavity multilayer filter. When forming the first filter, the center wavelength can be easily adjusted by setting the center wavelength to be slightly longer than the long wavelength and forming the film thicker and adjusting the gap thickness and the inclination angle.

Further, it is clear that the multi-cavity type multilayer filter can be applied not only to two cavities but also to a multi-cavity type multilayer filter having three or more cavity layers. It is sufficient that any one of the cavity layers is formed by a gap. The gap is composed of a filter block including one mirror layer or one mirror layer and a multilayer filter, and a filter block including the other mirror layer or the other mirror layer and a multilayer filter.

FIG. 10 shows the transmittance characteristics before correction of the multilayer filter according to the fourth embodiment of the present invention. The desired center wavelength was 1550 nm, and the mirror layer of each filter was formed by repeatedly stacking 20 dielectric layers. The gap 10 was filled with air, and the initial value of the gap thickness was set to ½ nm, which is 775 nm. The optical axis and the filter surface are orthogonal to each other, which is the transmission characteristic before the gap thickness is adjusted and corrected. It can be seen that, when the first filter was formed, the center wavelength was set to be slightly longer than the long wavelength, and there was a small peak near 1556.2 nm. The small peak near 1550 nm is due to the second filter with the thickness of the gap 10 set to 775 nm.

FIG. 11 shows corrected transmittance characteristics of the multilayer filter according to the fourth embodiment of the present invention. It is the transmission characteristic after the gap thickness and the inclination angle of the multi-cavity multilayer filter are adjusted and corrected. It can be seen that the center wavelength is the desired 1550 nm.

FIG. 12 shows the structure of a multilayer filter according to the fifth embodiment of the present invention. The fifth embodiment is 3
A third type of cavity type multi-layer filter having a cavity layer constituted by a gap between two filters having a cavity layer produced by a conventional film forming method.
The filter is sandwiched. First filter and second
The filter has a cavity layer 11 sandwiched between the mirror layers 17 and 18 and having a refractive index n _H. The second filter has a gap 10 sandwiched between the mirror layers 19 and 20 and having a refractive index n _G.

The method of manufacturing the three-cavity type multilayer filter is as follows: the mirror layer 1 is formed by sequentially laminating dielectric layers on one substrate.
7, the cavity layer 11 is formed on the mirror layer 17, and the dielectric layers are sequentially laminated on the cavity layer 11 to form the mirror layer 18. Further, the dielectric layers are sequentially laminated to form the mirror layer 19 to manufacture the filter block. In this way, the substrate on which the dielectric layers are laminated is divided, and the filter block laminated on the substrate 1a and the filter block laminated on the substrate 1b are opposed to each other to form the gap 10. The gap 10 is filled with, for example, vacuum, a gas such as air, or a liquid such as an ultraviolet curable resin.

With such a configuration, the center wavelengths of the first filter and the second filter are set to be slightly longer than the desired center wavelength, and the tilt angle and the gap of the three-cavity multilayer filter are set. The center wavelength can be easily adjusted by adjusting the thickness of 10.

FIG. 13 shows the transmittance characteristic before correction of the multilayer filter according to the fifth embodiment of the present invention. The desired center wavelength was 1550 nm, and the mirror layer of each filter was formed by repeatedly stacking 20 dielectric layers. The gap 10 was filled with air, and the initial value of the gap thickness was set to ½ nm, which is 775 nm. The optical axis and the filter surface are orthogonal to each other, which is the transmission characteristic before the gap thickness is adjusted and corrected. At the time of film formation of the first and second filters, the center wavelength is set to be slightly longer than the wavelength of 1550.93 nm.
It can be seen that there is a small peak in the vicinity. 1549.7
The large peak near nm indicates that the thickness of the gap 10 is 77
This is due to the third filter set to 5 nm.

FIG. 14 shows the corrected transmittance characteristics of the multilayer filter according to the fifth embodiment of the present invention. It is the transmission characteristics after the gap thickness and the tilt angle of the three-cavity multilayer filter are adjusted and corrected. The desired center wavelength is 1
It can be seen that it is 550 nm. By dividing one substrate in which the dielectric multilayer films are laminated and creating a multilayer filter, the central wavelengths of the first, second, and third filters can be accurately matched, and the yield is high and the cost is low. A multilayer filter can be manufactured.

When a plurality of substrates are placed in the film forming apparatus and films are formed at the same time, it is considered that the films are formed under the same conditions. Therefore, it is possible to use two blocks formed from each substrate. Needless to say. Further, it is apparent that the multilayer filter can be applied not only to three cavities but also to a multi-cavity multilayer filter having an odd number of cavity layers such as five cavities and seven cavities.

FIG. 15 shows a method for manufacturing a multilayer filter according to the first embodiment of the present invention. A method of manufacturing a multilayer filter having one or more cavity layers will be described. A multilayer film structure 1 is formed by laminating a mirror layer in which two dielectric layers having different refractive indices are repeatedly laminated a plurality of times on a substrate 1.
Is formed (S101), and two mirror layers having two different dielectric layers having different refractive indexes are repeatedly laminated on the substrate 2 to form a multilayer film structure 2 (S102). Substrates 1 and 2,
The chips 1 and 2 to be the mirror blocks are cut by cutting to a desired size (S103). Chip 1 and Chip 2
And the mirror layers are respectively faced with each other to form a cavity layer by a gap, and a multilayer filter is formed (S104).

While measuring the transmittance characteristics of the multilayer filter, the gap thickness and the inclination angle of the multilayer filter are adjusted so that a desired center wavelength can be obtained (S105, 10).
6). When the desired center wavelength is obtained, it is fixed with the fixed substrate shown in FIG. 7 or an ultraviolet curable resin to complete the multilayer filter (S107).

FIG. 16 shows a method of manufacturing a multilayer filter according to the second embodiment of the present invention. A method of manufacturing three or more odd-cavity filters in which filters each having a cavity layer on both sides are laminated around a filter having a cavity layer constituted by a gap will be described. Multilayer film structure 1 is formed by laminating a mirror layer in which two dielectric layers having different refractive indices are repeatedly laminated a plurality of times on substrate 1 (S201), and substrate 1 is cut into a target size to form a mirror. Create chips 1 and 2 to be blocks (S2
02). The chip 1 and the chip 2 are faced to the mirror layers, respectively, to form a cavity layer by the gap (S203). While measuring the transmittance characteristics of the multilayer filter, the gap thickness and the tilt angle are adjusted so that a desired center wavelength can be obtained (S204, 205). When the desired center wavelength is obtained, it is fixed with the fixed substrate shown in FIG. 7 or an ultraviolet curable resin to complete the multilayer filter (S206).

FIG. 17 shows an apparatus for manufacturing a multilayer filter according to an embodiment of the present invention. Further, FIG. 18 is an external view of a manufacturing apparatus for a multilayer filter. The manufacturing apparatus for a multilayer filter includes a holding unit 22 that holds each mirror block or filter block of the multilayer filter 21,
An inclination angle adjusting unit 23 for adjusting the inclination angle of the optical axis of the multilayer filter 21 by changing the inclination angle of the holding unit 22, and the holding unit 22.
And a gap thickness adjusting unit 24 that adjusts the gap thickness of the multilayer filter 21 by changing the interval. Further, in order to measure the transmittance characteristic of the multilayer filter 21, a light source 25, a light beam transmitting section 26, and a measuring section 27 are provided on the optical axis of the multilayer filter 21.

Control unit 28 of the manufacturing apparatus of the multilayer filter
Controls the tilt angle adjusting unit 23 and the gap thickness adjusting unit 24 so that a desired center frequency of the multilayer filter 21 can be obtained while measuring the transmittance characteristic by the measuring unit 27.
In this way, the gap thickness and the inclination angle are adjusted while manufacturing the multilayer filter 21 while measuring the center frequency, so that the cavity layer can be easily formed with desired accuracy, and the yield is improved and manufactured. The cost can be reduced.

[0048]

As described above, according to the present invention,
Since two mirror layers in which two dielectric layers having different refractive indexes are alternately and repeatedly laminated are opposed to each other to form a gap serving as a cavity layer, it is possible to improve the yield and reduce the manufacturing cost. It will be possible.

[Brief description of drawings]

FIG. 1 is a sectional view showing a configuration of a conventional multilayer filter.

FIG. 2 is a diagram showing a transmittance characteristic of a conventional multilayer filter.

FIG. 3 is a diagram showing transmittance characteristics when there is an error in a conventional multilayer filter.

FIG. 4 is a cross-sectional view showing a configuration of a multilayer filter according to the first exemplary embodiment of the present invention.

FIG. 5 is a diagram showing the relationship between the gap thickness and the center wavelength of the multilayer filter according to the first embodiment of the present invention.

FIG. 6 is a diagram showing transmittance characteristics of the multilayer filter according to the first embodiment of the present invention.

FIG. 7 is a cross-sectional view showing a configuration of a multilayer filter according to a second exemplary embodiment of the present invention.

FIG. 8 is a cross-sectional view showing the structure of a multilayer filter according to a third embodiment of the present invention.

FIG. 9 is a cross-sectional view showing the structure of a multilayer filter according to a fourth embodiment of the present invention.

FIG. 10 is a diagram showing transmittance characteristics before correction of the multilayer filter according to the fourth embodiment of the present invention.

FIG. 11 is a diagram showing corrected transmittance characteristics of the multilayer filter according to the fourth embodiment of the present invention.

FIG. 12 is a cross-sectional view showing the structure of a multilayer filter according to a fifth embodiment of the present invention.

FIG. 13 is a diagram showing transmittance characteristics before correction of the multilayer filter according to the fifth embodiment of the present invention.

FIG. 14 is a diagram showing corrected transmittance characteristics of a multilayer filter according to a fifth embodiment of the present invention.

FIG. 15 is a flowchart showing a method for manufacturing a multilayer filter according to the first embodiment of the present invention.

FIG. 16 is a flowchart showing a method for manufacturing a multilayer filter according to the second embodiment of the present invention.

FIG. 17 is a block diagram showing an apparatus for manufacturing a multilayer filter according to an embodiment of the present invention.

FIG. 18 is an external view showing a manufacturing apparatus of a multilayer filter according to an embodiment of the present invention.

[Explanation of symbols]

1, 1a, 1b, 2 substrates 3,4 Fixed substrate 5,6 Dielectric layer 8 Coupling layer 10,10a, 10b Gap 11 Cavity layer 17,18 Mirror layer 21 Multilayer filter 22 Holder 23 Tilt angle adjustment unit 24 Gap thickness adjuster 25 light sources 26 Light beam transmission part 27 Measuring section 28 Control unit

Claims (13)

[Claims] 1. A mirror block in which two dielectric layers having different refractive indexes are alternately and repeatedly laminated a plurality of times, and a mirror block is formed on a substrate, and the two mirror blocks are opposed to each other. A multi-layered film filter, comprising: a gap serving as a formed cavity layer. 2. The multilayer filter according to claim 1, wherein the side end faces of the two mirror blocks are fixed by a fixed substrate to form the gap. 3. The multilayer filter according to claim 1, wherein the two mirror blocks are fixed by filling the gap with an ultraviolet curable resin or a thermosetting resin. 4. The gap is configured by adjusting a gap interval and an inclination angle of an optical axis of the multilayer filter in order to set a center wavelength of the multilayer filter. The multilayer filter according to claim 1, 2 or 3. 5. A multi-layer film filter having two mirror layers in which two dielectric layers having different refractive indices are alternately and repeatedly laminated a plurality of times and a cavity layer sandwiched between the two mirror layers is coupled. A multi-cavity multi-layer film filter in which a plurality of layers are coupled via a layer, wherein one cavity layer is composed of a gap and the other cavity layer is a dielectric layer. 6. A filter block including one mirror layer forming the gap or one mirror layer and a multilayer filter, and the other mirror layer forming the gap or the other mirror layer and a multilayer filter. The multi-cavity multilayer film filter according to claim 5, wherein each side end surface of the filter block including and is fixed by a fixing substrate to form the gap. 7. The multi-cavity type multilayer film filter according to claim 5, wherein the two gaps are fixed by filling the gap with an ultraviolet curable resin or a thermosetting resin. 8. The gap interval for setting the center wavelength of the multi-cavity multilayer filter,
The multi-cavity multilayer filter according to claim 5, 6 or 7, wherein the gap is formed by adjusting an inclination angle of an optical axis of the multi-cavity multilayer filter. 9. Two filter blocks having a mirror layer, in which two dielectric layers having different refractive indexes are alternately and repeatedly laminated a plurality of times, are formed on a substrate to form a gap which is a cavity layer by facing the mirror layers. A method of manufacturing a multilayer filter, wherein one mirror layer forming the gap or a filter block including the one mirror layer and a multilayer filter is formed on a substrate, and the other mirror forming the gap. A layer or a filter block including the other mirror layer and a multilayer filter on a substrate, the one mirror layer and the other mirror layer are opposed to each other to form the gap, and one or more A method of manufacturing a multilayer filter, comprising: forming a multilayer filter having the cavity layer of 1. 10. The gap is configured by adjusting a gap interval and an inclination angle of an optical axis of the multilayer filter in order to set a center wavelength of the multilayer filter. The method for manufacturing the multilayer filter according to claim 9. 11. The method for manufacturing a multilayer filter according to claim 10, wherein the center wavelength is set by measuring the transmittance characteristic of the multilayer filter. 12. The method for producing a multilayer filter according to claim 9, 10 or 11, wherein the two mirror layers are formed by dividing one substrate on which the mirror layers are formed. 13. A substrate having a mirror layer in which two dielectric layers having different refractive indexes are alternately and repeatedly laminated a plurality of times.
Holding means for holding the two mirror blocks oppositely to each other, holding means for holding the mirror layers facing each other, gap thickness adjusting means for changing the distance between the holding means and adjusting the distance between the gaps formed by the two mirror layers, and the holding means. Changing the tilt angle of the means, tilt angle adjusting means for adjusting the tilt angle of the optical axis of the multilayer filter including the filter block and the gap, measuring means for measuring the transmittance characteristics of the multilayer filter, Based on the transmittance characteristics measured by the measuring means, the gap is adjusted by the gap thickness adjusting means, the tilt angle is adjusted by the tilt angle adjusting means, and the center wavelength of the multilayer filter is set. An apparatus for manufacturing a multilayer filter, comprising: a control unit.