JP2002071944A - Apparatus and method for manufacturing optical bandpass filter - Google Patents

Abstract

(57) [Summary] [Problem] To suppress a variation in film thickness within an allowable range of 0.01% and secure a channel interval of 0.8 nm, and to form a substrate having a predetermined thickness on a flat glass substrate base material. Provided is an apparatus for manufacturing a bandpass filter capable of forming a sloped BPF film by vapor deposition. A support surface (22) that rotates about a rotation shaft (22b) and supports a flat substrate (30) on its lower surface.
a, and a band-pass filter film material 3 with respect to the other surface of the substrate base material having one surface supported on the support surface.
3. Manufacture of an optical band-pass filter comprising: a deposition source 23 disposed below the rotating pedestal for depositing 3; and a film thickness monitoring means 24 disposed along a line extending the rotation axis of the rotating pedestal. In the apparatus, the support surface of the rotary pedestal is a surface inclined at a required angle with respect to a horizontal plane. A band pass filter film having a required thickness gradient is formed on the surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a manufacturing apparatus and a manufacturing method of an optical bandpass filter used as a narrow band optical filter, and more particularly, to an application to a high-density multiplex transmission in which an adjacent channel interval is about 0.8 nm. The present invention also relates to an apparatus and a method for manufacturing an optical band-pass filter capable of accurately separating multiplexed light for each channel even in the case of the above.

[0002]

2. Description of the Related Art In optical multiplex communication, multiple channels of light having different wavelengths are multiplexed and transmitted to one optical fiber to achieve multi-channel transmission. 2. Description of the Related Art An optical demultiplexer is used as a channel demultiplexing means for selecting light having a desired wavelength from light of a plurality of wavelengths multiplexed and transmitted in an optical fiber and removing unnecessary light. This optical demultiplexer uses an optical bandpass filter (BPF) 1 to transmit light of a specific wavelength while reflecting light of other wavelengths. The bandpass filter has a structure in which a BPF film 3 is formed on one surface of a substrate 2 made of a transparent material such as a glass plate, as shown in FIG. As shown in b), it has the property of transmitting light of wavelength λ1 and reflecting other wavelengths. The BPF film 3 is a multiple interference film obtained by alternately laminating about 100 to 150 layers of a high refractive material film and a low refractive material film.
The characteristics of the films can be changed by varying the thickness of each film. Recent high-density optical multiplex transmission (DWD)
In the field of M), since various types of wavelengths such as 16ch and 32ch are multiplex-transmitted, an optical demultiplexer for demultiplexing each wavelength into channels is used. FIG. 9 is an explanatory diagram of a demultiplexer used for high-density optical multiplex transmission for transmitting n kinds of wavelengths. The demultiplexer 5 converts the multiplexed light input from the input optical fiber 6 into n wavelengths. λ
It has n bandpass filters BPF1 to BPFn for separating the channels into light of 1 to λn. Each of the band-pass filters BPF1 to BPFn receives the multiplexed light emitted from the optical fiber 6 and transmits only light of a specific wavelength according to the characteristics of the BPF film 3 included in each, and filters light of other wavelengths. It is arranged so that it is reflected and emitted toward the next bandpass filter. That is, in this example, the band-pass filter BPF1 having the characteristic of transmitting only the wavelength λ1 is arranged at the first stage of the output path of the input optical fiber 6, and the wavelengths λ2, λ3,.
1, each band pal filter BPF2 transmitting λn,
BPF3,... BPFn-1, BPFn are arranged along the path of the reflected light. Each bandpass filter BPF1
The BPFn is connected to the output optical fibers 7λ1 to 7λn, respectively, and the light of a specific wavelength transmitted through each bandpass filter is output to the outside via the corresponding output optical fiber 7λ1 to 7λn. As described above, the conventional demultiplexer used for high-density multiplex transmission requires the same number of bandpass filters as the number of channels n, and the individual bandpass filters have different characteristics, and thus have to be manufactured individually.

Next, a method for manufacturing a conventional bandpass filter will be described. First, FIG. 10 is a view for explaining a conventional band-pass filter manufacturing apparatus. In this manufacturing apparatus, a single vapor deposition apparatus 11 is used, and wavelengths λ1, λ2,
... N kinds of bandpass filters for λn are sequentially manufactured. This vapor deposition apparatus 11 fixes a plurality of glass substrate base materials 2A in a predetermined arrangement on the lower surface of a dome-shaped support member 13 arranged at the upper part in a vacuum chamber 12, and has a high refractive index material And a deposition source 15 for a low-refractive-index material. Then, in the vacuum chamber 12 in a vacuum state, dielectrics for vapor deposition are alternately emitted from the vapor deposition sources 14 and 15 so that a high refractive index material film and a low refractive index material film are formed on the surface of the glass substrate base material 2A. Refractive index material films are alternately formed. The characteristics of each bandpass filter,
That is, the type of wavelength transmitted by each bandpass filter is
Since it is determined by the difference in the configuration of the BPF film 3 deposited on the surface of the glass substrate 2 (the difference in the thickness of the high-refractive material film and the low-refractive material film that are alternately laminated), one deposition apparatus 1
Only one kind of bandpass filter can be manufactured in one vapor deposition step using No. 1. Therefore, in order to manufacture n kinds of bandpass filters, it is necessary to perform the process n times. For example, if it takes one day to form one type of bandpass filter, it takes n days to complete the film formation for n types of bandpass filters. Therefore, it takes 16 days to complete the film formation for the band-pass filter for 16 channels, and 32 days for the band-pass filter for 32 channels, which is extremely low in productivity and the number of days required for completion is proportional to the number of channels. There is a disadvantage that the time is extended. For this reason,
N deposition apparatuses 11 shown in FIG. 9 are prepared, and n kinds of bandpass filters are simultaneously manufactured in parallel. According to this method, although the manufacturing period can be significantly shortened as compared with the above manufacturing method, the number and scale of the equipment increase in proportion to the number of channels, which increases the capital investment cost and the site required for the equipment. There is a problem that causes the spread of the. Japanese Patent Application Laid-Open No. 6-265722 discloses a bandpass filter capable of solving such a problem.
As shown in the schematic cross-sectional view of (a), a high refractive material film 3a and a low refractive material film 3b whose thickness gradually increases from one edge to the other opposite edge are formed on one surface of the flat glass substrate 2. A configuration is disclosed in which a BPF film 3 having an inclined surface having a thickness inclined at a certain angle as a whole is formed by alternately laminating. FIG. 11 (b) is a schematic configuration diagram of the vapor deposition apparatus described in this publication, and shows a state where each glass substrate base material 2A is inclined with respect to the emission surfaces of the vapor deposition sources 14 and 15 using a jig 16. In order to fix to the rotating dome 13, the thickness of the BPF film laminated on the surface of each glass substrate 2 is not uniform, and the thickness of the substrate surface closer to the evaporation sources 14 and 15 increases. The film thickness becomes thinner as the substrate surface portion is farther. This is because the film thickness is formed in inverse proportion to the distance from the evaporation source. It should be noted that evaporation is performed while rotating the rotating dome 13 about the rotation axis 17, thereby reducing evaporation unevenness. Reference numeral 18 denotes a film thickness monitoring sensor, which measures the film thickness on a specific glass substrate base material by using the film thickness monitoring sensor 18 to obtain a film thickness on another glass substrate base material supported by the dome. The film thickness is estimated.

FIGS. 11 (c) and 11 (d) show a structure of a base material of a band-pass filter manufactured by such a vapor deposition apparatus.
According to the bandpass filter base material 1A having the BPF film 3A having such a thickness gradient, as shown in FIG. 11C, the BPF film 3A has different bandpass characteristics depending on the portions having different thicknesses. The wavelength of the transmitted light varies depending on the portions having different film thicknesses. That is, it is possible to obtain a bandpass filter base material 1A including a plurality of types of BPF films 3A on one glass substrate base material 2A. Therefore, a plurality of sets of n types of bandpass filters 1 having different transmission wavelengths can be obtained by dividing vertically and horizontally along the cutting line L as shown in (d).
However, according to the manufacturing method described in the above publication, only a wide band having a wavelength interval of about 3.2 nm between adjacent channels can be manufactured. Narrow band channel spacing cannot be achieved. Further, as described above, by measuring the film thickness on the specific glass substrate base material by the film thickness monitoring sensor 18, the film thickness on another glass substrate base material supported by the dome 13 is estimated. However, there was a large variation in the film thickness between the base materials of the band-pass filters manufactured while performing such film thickness measurement. When fabricating a narrow-band filter, an error of 0.01% is an allowable range as a control accuracy of the film thickness, but it is extremely difficult to control the film thickness within a 0.01% error range by the method described in the above publication. It is.

[0005]

SUMMARY OF THE INVENTION The problem to be solved by the present invention is to suppress the variation of the film thickness to within an allowable range of 0.01%, to secure 0.8 nm as a channel interval, and to form a flat plate. It is an object of the present invention to provide an apparatus and a method for manufacturing a bandpass filter capable of forming a BPF film having a predetermined inclination on a glass substrate base material by vapor deposition.

[0006]

According to a first aspect of the present invention, there is provided a rotary pedestal which rotates about a rotary shaft and has a support surface on its lower surface for supporting a flat substrate. A deposition source disposed below the rotary pedestal for depositing a bandpass filter film material on the other surface of the substrate base material having one surface supported on the support surface. The device, wherein the support surface of the rotary pedestal is a surface inclined at a required angle with respect to a horizontal plane,
By performing evaporation from an evaporation source while rotating the substrate base material supported on the rotary pedestal, a band-pass filter film having a required thickness gradient is formed on the other surface of the substrate base material. I do. According to a second aspect of the present invention, there is provided a rotating pedestal having a horizontal support surface that rotates about a vertical rotation axis and supports a flat substrate base material on a lower surface thereof, and a substrate mother having one surface supported on the support surface. An evaporation source disposed below the rotary pedestal for vapor-depositing the bandpass filter film material on the other horizontal surface of the material, and a shielding member disposed at a position immediately adjacent to the other surface of the substrate base material. An optical band-pass filter manufacturing apparatus comprising: performing evaporation from an evaporation source while rotating a substrate base material supported on the rotating pedestal,
When a bandpass filter film having a required thickness gradient is formed on the other surface of the substrate base material, the amount of the bandpass filter material deposited is controlled by the shielding member. The invention according to claim 3 is characterized in that the shielding member has a rod shape or a plate shape.

According to a fourth aspect of the present invention, there is provided a rotary pedestal which rotates about a rotation axis inclined at a predetermined angle with respect to a vertical line and has an inclined support surface on its lower surface for supporting a flat substrate. An evaporation source disposed below the rotating pedestal and at a position avoiding the extension of the rotating shaft to deposit a bandpass filter film material on the other inclined surface of the substrate base material having one surface supported on the supporting surface; A shielding member disposed at a position immediately adjacent to the other surface of the substrate base material, and a deposition source while rotating the substrate base material supported on the rotary base. By performing vapor deposition from the above, when forming a bandpass filter film having a required film thickness gradient on the other surface of the substrate base material, the amount of bandpass filter material vapor deposition is controlled by the shielding member. The feature is that . According to a fifth aspect of the present invention, there is provided a rotary pedestal having a horizontal support surface that rotates about a vertical rotation axis and supports a flat substrate base material on a lower surface thereof, and a substrate base supported on one side by the support surface. A vapor deposition source disposed below the rotary pedestal and at a position avoiding the extension of the rotation axis to vapor-deposit the bandpass filter film material on the other horizontal surface of the material, facing the other surface of the substrate base material; And a shielding member disposed at a position immediately adjacent to the substrate base material, comprising: performing evaporation from an evaporation source while rotating the substrate base material supported on the rotary pedestal; When a bandpass filter film having a required film thickness gradient is formed on the other surface, the amount of deposition of the bandpass filter material is controlled by the shielding member.
According to a sixth aspect of the present invention, in the apparatus for manufacturing an optical bandpass filter according to any one of the first, second, third, fourth, and fifth aspects, the film thickness is increased along a line extending a rotation axis of the rotation pedestal. A monitor means is provided. According to a seventh aspect of the present invention, there is provided a rotating base having a support surface that rotates about a rotation axis and has a support surface on its lower surface for supporting a flat substrate base material, and a substrate base material having one surface supported on the support surface. A vapor deposition source disposed below the rotary pedestal to vapor-deposit a bandpass filter film material on a surface, and a method for manufacturing an optical bandpass filter using the support surface of the rotary pedestal.
A band having a required film thickness gradient on the other surface of the substrate base material by performing evaporation from a deposition source while rotating the substrate base material supported on the rotary pedestal with a surface inclined at a required angle with respect to a horizontal plane. A pass filter film is formed.

[0008] According to a eighth aspect of the present invention, there is provided a rotating pedestal having a horizontal support surface for rotating about a vertical rotation axis and supporting a flat plate base material on its lower surface, and supporting one surface on the support surface. A deposition source disposed below the rotating pedestal for vapor-depositing the bandpass filter film material on the other horizontal surface of the substrate preform, and a vapor deposition source disposed at a position immediately adjacent to the other surface of the substrate preform. A shielding member, and a method of manufacturing an optical band-pass filter using the method, wherein vapor deposition is performed from a vapor deposition source while rotating the substrate base material supported on the rotating pedestal, so that a required surface is formed on the other surface of the substrate base material. When a band-pass filter film having a film thickness gradient is formed, the amount of deposition of the band-pass filter material is controlled by the shielding member. The method according to the ninth aspect of the present invention is characterized in that the shielding member has a rod shape or a plate shape. Claim 1
The invention method according to claim 0, wherein the rotating base rotates about a rotation axis inclined at a predetermined angle with respect to a vertical line and has a slanted support surface on its lower surface for supporting a flat substrate base material; A deposition source disposed below the rotating pedestal and at a position avoiding the extension of the rotating shaft for depositing the band-pass filter film material on the other inclined surface of the substrate matrix supporting the substrate matrix; A shielding member disposed at a position immediately adjacent to the other surface of the material, and a method of manufacturing an optical bandpass filter, wherein vapor deposition is performed from a vapor deposition source while rotating a substrate base material supported on the rotating pedestal. Thereby, when forming a bandpass filter film having a required thickness gradient on the other surface of the substrate base material, the amount of bandpass filter material vapor deposition is controlled by the shielding member. And A method according to claim 11, wherein the rotating base has a horizontal support surface for rotating about a vertical rotation axis and supporting a flat plate base material on the lower surface thereof, and a substrate supported on one side by the support surface. An evaporation source disposed below the rotating pedestal and at a position avoiding the extension of the rotating shaft to deposit the bandpass filter film material on the other horizontal surface of the base material, and the other surface of the substrate base material. A method of manufacturing an optical band-pass filter using a shielding member disposed at a position immediately adjacent to the substrate base, the method comprising: performing evaporation from an evaporation source while rotating the substrate base material supported on the rotary pedestal; When a band-pass filter film having a required thickness gradient is formed on the other surface of the material, the amount of band-pass filter material deposited is controlled by the shielding member. Claim 1
According to a second aspect of the present invention, in the method of manufacturing an optical bandpass filter according to any one of claims 7, 8, 9, 10, and 11, a film thickness is formed along a line extending a rotation axis of the rotation pedestal. A monitor means is provided.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings. FIG. 1 is a schematic configuration diagram of a band-pass filter manufacturing apparatus according to an embodiment of the present invention. The manufacturing apparatus includes a vacuum chamber 21, a rotating pedestal 22 disposed in an upper part of the vacuum chamber 21, An evaporation source 23 disposed at a lower part in the tank 21 and a film thickness monitor 24 are provided. The rotating pedestal 22 is a pedestal having a circular shape in plan view and having a support surface 22a (lower surface) inclined at a predetermined angle θ with respect to the upper surface, and a circular flat glass substrate base material (substrate base material) is provided on the support surface 22a. 30) is configured to be fixed in a state where one surface of the substrate 30 is tightly fixed with a temporary adhesive or the like. When fixing the glass substrate base material 30, the center C is
Is positioned so as to coincide with the rotation axis 22b which is the center of rotation of. The rotary pedestal 22 is configured to be rotatable around its rotary shaft 22b by a drive motor (not shown). The glass substrate base material 30 is, for example, a circular flat plate having a diameter of about 30 cm. The deposition source 23 includes, for example, a crucible (not shown) that stores a dielectric deposition material, a heater (not shown) that heats the crucible to evaporate the deposition material, and the like. In this example, since the operation of alternately depositing the high-refractive-index material and the low-refractive-index material is performed, the deposition source 23a for the high-refractive-index material is used.
Then, the deposition source 23b for the low-refractive-index material is arranged in proximity. The position where the deposition source 23 is disposed is the rotation axis 22 b of the rotation base 22.
Position along the extension of.

The film thickness monitoring means 24 comprises a monitor light source 31 disposed immediately above a through hole 22b 'formed along the axis of a rotating shaft 22b of the rotary base 22, and a monitor light disposed immediately below the through hole 22b'. And a light receiving element 32. Light source 3
The light emitted from 1 passes through the glass substrate base material 30 through the through-hole 22b ', reaches the light receiving element 32, and monitors the characteristics of the BPF film deposited and formed on the lower surface of the glass substrate base material 30. . The light receiving element 32 is a small element having a diameter of about 1 cm, and is disposed below the evaporation source 23 sufficiently (for example, about 1 m) apart from the base material of the glass substrate, so that the evaporation material emitted from the evaporation source 23 is glass. There is no hindrance when being deposited on the lower surface of the substrate base material. In addition, evaporation source 2
3 and the glass substrate base material 30 (distance between both)
Is set such that the lower surface of the glass substrate base material is included in the effective development range of the deposition material emitted from the deposition source 23. By setting as described above, it is possible to obtain a uniform film quality and a uniform film thickness without variation over the entire lower surface of the glass substrate base material. In other words, since one glass substrate base material 30 is disposed immediately above one set of evaporation sources 23 and evaporation is performed in a one-to-one relationship, it is possible to ensure uniform film quality and film thickness. In addition, since the deposition is performed while directly monitoring by the film thickness monitoring means 24, the wavelength interval can be set to a narrow band of 0.8 nm. Therefore, when applied to a demultiplexer used for high-density optical multiplexing transmission (DWDM) in which a large number of wavelengths such as 16 channels and 32 channels are multiplexed, it is possible to accurately separate each wavelength having a narrow pass band. Becomes

In this vapor deposition apparatus, the rotary pedestal 22 is
2b while rotating each of the evaporation sources 23a and 23b.
, The BPF film 33 finally obtained has a shape as shown by the dotted line (the thickness is greatly exaggerated). That is, since the lowermost part of the glass substrate base material 30 fixed to the inclined support surface 22a is always at the lowermost position during the rotation of the rotating pedestal 22, the film thickness formed in this part becomes maximum, and conversely, the glass substrate The film thickness formed on the uppermost part of the base material 30 is minimized. Therefore, the tapered BPF film 33 is formed as shown by the dotted line. The monitor light source 31 and the light receiving element 32 constituting the film thickness monitoring means 24 are connected to the rotation center 2 of the rotation base 22.
2b, the drive shaft of the motor for rotation cannot be arranged in a portion corresponding to the rotation center 22b of the rotary base 22, but the outer periphery of the rotary base 22 is rotatably supported by a bearing (not shown). In addition, if the driving force from the motor is transmitted to the rotating base via a gear, a pulley, a belt, or the like, the rotating base can be rotated. In the above example, the rotation axis 22b of the rotary pedestal and the center C (center of rotation) of the glass substrate preform 30 are matched, but the center of the glass substrate preform 30 and the rotation axis 2
If the deposition is carried out while rotating while being shifted from 2b, a BPF film having an asymmetrical gradient can be obtained, and such a BPF film also has a sufficient utilization value. In order to make the film quality of the PBF film more uniform and to control the film thickness more precisely, the rotation speed of the rotating pedestal 22 supporting the glass substrate base material 30 may be made higher, and the rotation speed may be as follows. For example, a range of 300 to 1000 rotations / minute is preferable. The base material of the band-pass filter obtained in this manner is cut along a cutting line extending in the radial direction from the center and a cutting line extending in the circumferential direction, as described later, so that BPF films having different characteristics can be formed. It is divided into a plurality of pieces. In the above embodiment, the description has been made mainly on the vapor deposition apparatus as the production apparatus of the present invention, but the above description also discloses a vapor deposition method (a method for producing an optical bandpass filter). This point is common to all the following embodiments.

Next, FIGS. 2A and 2B are explanatory views of the structure of a vapor deposition apparatus according to another embodiment of the present invention. This vapor deposition apparatus is composed of a vacuum chamber 35 and a vertical chamber in the vacuum chamber 35. A rotating base 36 that rotates about a rotating shaft 36b and adheres and fixes one surface of a glass substrate base material (substrate base material) 37 of a circular flat plate shape to the support surface 36a, and the vapor deposition source 3 positioned below the rotating base 36.
8 (an evaporation source 38a for a high refractive material and an evaporation source 38b for a low refractive material), a film thickness monitor 39 (a light source 39a, a light receiving element 39b), and a shielding bar (shielding member) 40. As in the above-described embodiment, the diameter of the glass substrate base material 37 is about 30 cm, and the distance between each deposition source and the glass substrate base material is about 1 mm. equal. Therefore, since the supporting surface 36a on the lower surface of the glass substrate base material 37 is horizontal,
6a, a flat glass substrate base material 3 having one surface adhesively fixed thereto
The lower surface (deposition surface) of 7 is also horizontal, and the deposition material emitted from each of the deposition sources 38a and 38b is alternately deposited while rotating about the rotation axis 36b, thereby forming a BPF film having a uniform thickness. Should be done. However, in the present embodiment, since the shielding bar 40 is arranged directly below the glass substrate base material 37 in parallel with the lower surface of the glass substrate base material and at a position avoiding the rotation axis 36a, the film thickness is uniform. Not
A BPF film 41 having a film thickness distribution as shown in FIG. In other words, in FIGS. 2B and 2C, the area a near the rotation center 36b is the area where the shielding rod 4 is rotated during rotation of the glass substrate base material 37.
Since the shielding material is not shielded by 0, this is a region where the vapor deposition material from the vapor deposition source 38 adheres in the largest amount. Therefore, as shown in (c), the thickness of the BPF film 41 corresponding to the region a becomes the maximum. Next, since the area b is covered by the shielding bar 40 for about one fourth of one rotation, the film thickness is about １ ／ of the film thickness of the area a. Then, as the shielding time by the shielding bar 40 gradually decreases from the region d located in the outer diameter direction to the region c, the film thickness gradually increases.

Next, FIGS. 3 (a), 3 (b) and 3 (c) are explanatory views of a shielding member as a modification of the embodiment of FIG.
The case where this shielding member is applied instead of the shielding bar of the vapor deposition apparatus shown in FIG. That is, the shielding member of this embodiment is the shielding plate 45, which is disposed below the rotating pedestal instead of the shielding bar shown in FIG. First, FIG.
(a) A fan-shaped (square-shaped fan-shaped top) shielding plate 4 expanding outward from the center C of the glass substrate base material 37 as shown in the left figure.
When using No. 5, a BPF film 41 having a uniform film thickness is formed as shown in the right diagram of FIG. If the central angle of the shielding plate 45 is increased, the thickness of the BPF film 41 is reduced. On the other hand, as shown in the left diagram of FIG. 3B, the shape of the shielding plate 45 is changed so that the linear side edges 47 extending from the linear edge 46 along the center C of the glass substrate base material 37 have the outer diameter direction. When the glass substrate base material 37 is rotated, the shielding time of the substrate surface portion shielded by the triangular region 48 becomes longer when the glass substrate base material 37 rotates, so that the cross-sectional shape of the BPF film 41 is as shown in FIG. b) As shown in the figure on the right, it becomes a mortar-like shape in which the film thickness gradually increases from the center toward the outer diameter direction. 3 (c), the shape of the shielding plate 45 is adjusted so that both side edges 49 extending from the center C are concavely curved from the center C of the glass substrate base material 37 and extend in the outer radial direction. In the case of the configuration, the time in which the area near the center C is shielded by the shielding plate 45 is gradually shortened as compared with the area on the outer diameter side. Therefore, as shown in the right diagram of FIG. The BPF has a maximum film thickness, and has a BPF cross-sectional shape in which the film thickness gradually decreases in a curve toward the outer diameter direction.

Next, FIGS. 4A and 4B are schematic diagrams illustrating the structure of a vapor deposition apparatus and the structure of a shielding member according to another embodiment of the present invention. The rotating shaft 36b of the disk-shaped rotating pedestal 36 constituting the vapor deposition apparatus shown in (1) is inclined by one angle θ1 from a vertical line, and the film thickness monitoring means 39 is disposed along the rotating shaft 36b.
The vapor deposition source 38 is disposed at an appropriate position along an extension that vertically hangs the center C of the glass substrate base material 37. The shielding plate 45 as a shielding member is arranged so as to shield half the area of the glass substrate base material 37 in a substantially horizontal posture as shown in FIG. According to the vapor deposition apparatus in this embodiment, each vapor deposition source 3
The vapor deposition surface of the glass substrate base material 37 is obliquely inclined with respect to the vapor deposition source 38a for the high refraction material and the vapor deposition source 38b for the low refraction material, which constitutes No. 8; As shown in FIG. 4C, the thickness of the BPF film 41 becomes thicker at the outer peripheral edge of the glass substrate base material 37, becomes thinner at the center, and becomes concave. According to the vapor deposition apparatus of this embodiment, the film thickness formed by the film thickness monitoring means 39 can be directly monitored, so that a bandpass filter having a wavelength separation capability of a wavelength of 0.8 nm can be manufactured. Next, FIGS. 5 (a), 5 (b) and 5 (c) are modified examples of the vapor deposition apparatus according to the embodiment of FIG. 4, in which the rotating shaft 36b of the rotating pedestal 36 is a vertical axis and the shielding plate 40 is A characteristic feature is that the deposition source 38 is inclined downward by a predetermined angle θ2 with respect to a horizontal plane, and furthermore, the deposition source 38 is displaced to one side by a required distance L1 from the rotation shaft 36b to perform oblique deposition. The vapor deposition procedure and effects of the vapor deposition device of this embodiment are almost the same as those of the vapor deposition device of FIG. That is, as shown in FIG. 5C, a shielding plate 45 for shielding half of the glass substrate base material 37 is disposed between the glass substrate base material 37 and the evaporation source 38 as shown in FIG. The BPF film 41 having a film thickness that forms a concave curved surface can be obtained. According to the vapor deposition apparatus of this embodiment, the film thickness formed by the film thickness monitoring means 39 can be directly monitored, so that a bandpass filter having a wavelength separation capability of a wavelength of 0.8 nm can be manufactured.

Next, FIGS. 6 (a), 6 (b) and 6 (c) show band-pass filter base materials obtained by the above-mentioned respective manufacturing apparatuses.
A BPF film 41 having a required film thickness distribution is provided on a glass substrate base material 37 of about mm. The BPF film constituting such a band-pass filter base material has a constant film thickness and film quality at a portion along the circumferential direction, but changes in film thickness and film quality toward the radial direction. Therefore, the fan-shaped divided piece 50 ((b)) obtained by dividing along the plurality of cutting lines S1 extending in the radial direction around the center C and having a circumferential interval of the predetermined angle θ3 is further separated. As shown in (c), individual BPF pieces 51 can be obtained by cutting and dividing at a predetermined radial pitch along the cutting line S2.
Since the individual piece 51a located on the outer diameter side of the divided piece 50 has a large area, it may be further divided into two and used. The pitch at which the divided piece 50 is radially divided by the cutting line S2 is 16 c
When applied to a demultiplexer used for high-density optical multiplexing transmission (DWDM) in which a large number of wavelengths such as h and 32 ch are multiplexed, for example, adjacent BPF pieces 51 have wavelengths of 0.
The setting is made so as to realize the channel separation of 8 nm.

Next, FIGS. 7A, 7B and 7C are perspective views and sectional views of the individual BPF pieces cut and divided by the method of FIG. 6 (the thickness of the BPF film is exaggerated). 4) and 4 (a) are schematic diagrams showing the use of the individual pieces shown in FIG. In this embodiment,
As shown in FIG. 7 (a), each of the divided pieces 51 is cut and divided along each cutting line S1 so that the radial length becomes larger.
The split piece 51 is a band-pass filter having a continuous BPF film portion having an ability to pass wavelengths λ1, λ2, and λ3 in bands suitable for a plurality of different channels. For this reason, the band-pass to the optical fiber 55 is achieved by configuring the split piece 51 facing the emission end face of the optical fiber 55 that outputs the multiplexed light so as to be able to advance and retreat in the plane direction indicated by the arrow by a movable mechanism (not shown). The wavelength to be transmitted can be arbitrarily switched only by shifting the position of the filter 51. As described above, since the wavelength to be separated can be switched and used only by shifting the position of the band-pass filter 51 as one component, for example, when this is applied to an optical demultiplexer, the optical demultiplexer is used. Can be used by variously changing the passband, the number of channels, and the like to which can be applied, and the versatility can be expanded. In each of the above embodiments, the manufacturing apparatus of the optical bandpass filter has been described. However, the description of each embodiment refers to the manufacturing procedure of the optical bandpass filter over time. Accordingly, the description of each embodiment also discloses a method of manufacturing an optical bandpass filter.

[0017]

As described above, according to the vapor deposition apparatus and the manufacturing method of the present invention, the variation in the film thickness is kept within the allowable range of 0.01%, and the flatness of the flat plate is ensured while ensuring the channel spacing of 0.8 nm. It becomes possible to form a BPF film having a predetermined thickness on a glass substrate base material by vapor deposition. Therefore, it is effective in providing a narrow band optical filter required for an optical demultiplexer for high-density multiplex transmission (DWDM), and it is possible to manufacture a large number of filters having different pass bands in one process. Becomes

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an apparatus for manufacturing a bandpass filter according to an embodiment of the present invention.

FIGS. 2A and 2B are explanatory diagrams of a configuration of a vapor deposition apparatus according to another embodiment of the present invention.

3 (a), (b) and (c) are explanatory views of a shielding member as a modification of the embodiment of FIG.

FIGS. 4 (a) and (b) are schematic diagrams of a vapor deposition apparatus and a configuration of a shielding member according to another embodiment of the present invention.

5 (a), (b) and (c) are explanatory views of a modification of the vapor deposition device according to the embodiment in FIG.

FIGS. 6A, 6B, and 6C are diagrams showing a band-pass filter base material obtained by each manufacturing apparatus and a processing method thereof.

FIGS. 7 (a), (b) and (c) are diagrams for explaining another method of using the bandpass filter obtained according to the present invention.

8 (a) and (b) are explanatory diagrams of a conventional example.

FIG. 9 is an explanatory diagram of a demultiplexer used for high-density optical multiplex transmission for transmitting n kinds of wavelengths.

FIG. 10 is an explanatory diagram of another conventional example.

11 (a), (b), (c) and (d) are explanatory views of another conventional example.

[Explanation of symbols]

21 vacuum tank, 22 rotating base, 22a support surface, 22
b rotation axis, 23, 23a, 23b evaporation source, 24 film thickness monitoring means, 30 glass substrate base material (substrate base material), 3
1 monitor light source, 32 monitor light receiving element, 34 BP
F film, 35 vacuum chamber, 36 rotation base, 36a support surface, 36b rotation axis, 37 glass substrate base material (substrate base material), 38, 38a, 38b evaporation source, 39 film thickness monitoring means, 40 shielding rod (shielding member) ), 41 BPF membrane, 4
5 shielding plate, 46 edges, 47 both edges, 48 areas,
50 divided pieces, 51 BPF pieces.

Claims (12)

[Claims] 1. A rotating pedestal that rotates about a rotation axis and has a support surface on its lower surface for supporting a flat substrate, and a second surface of the substrate that is supported on one side by the support surface. And a deposition source disposed below the rotary pedestal for depositing the bandpass filter film material by using a rotary pedestal.A supporting surface of the rotary pedestal is required with respect to a horizontal plane. The surface is inclined at an angle, and by performing evaporation from an evaporation source while rotating the substrate base material supported on the rotary pedestal, a band-pass filter film having a required thickness gradient is formed on the other surface of the substrate base material. An apparatus for manufacturing an optical band-pass filter, wherein a film is formed. 2. A rotating pedestal having a horizontal support surface for rotating around a vertical rotation axis and supporting a flat substrate base material on a lower surface thereof, and a substrate base material having one surface supported on the support surface. An evaporation source arranged below the rotating pedestal for evaporating the band-pass filter film material on the other horizontal surface, and a shielding member arranged at a position closest to the other surface of the substrate base material. An apparatus for manufacturing an optical band-pass filter, comprising: performing vapor deposition from a vapor deposition source while rotating a substrate base material supported on the rotary pedestal, so that a required thickness gradient is formed on the other surface of the substrate base material. An apparatus for manufacturing an optical bandpass filter, wherein, when forming the bandpass filter film, the amount of bandpass filter material deposited is controlled by the shielding member. 3. The optical band-pass filter manufacturing apparatus according to claim 2, wherein the shielding member has a rod shape or a plate shape. 4. A rotating pedestal that rotates about a rotation axis that is inclined at a predetermined angle with respect to a vertical line and has an inclined support surface on its lower surface for supporting a plate-like substrate base material, and one surface on the support surface. An evaporation source disposed below the rotating pedestal and at a position avoiding the extension of the rotating shaft for depositing the band-pass filter film material on the other inclined surface of the supported substrate preform; And a shielding member disposed at a position closest to the other surface of the optical band-pass filter, wherein the deposition is performed from a deposition source while rotating a substrate base material supported on the rotating pedestal. According to the present invention, when a bandpass filter film having a required thickness gradient is formed on the other surface of the substrate base material, the amount of the bandpass filter material deposited is controlled by the shielding member. Light bandpass Filter manufacturing apparatus. 5. A rotating pedestal rotating about a vertical rotation axis and having a horizontal support surface on its lower surface for supporting a plate-shaped substrate preform, and a substrate preform supported on one side by said support surface. A vapor deposition source disposed below the rotating pedestal and at a position avoiding the extension of the rotating shaft to vapor-deposit the band-pass filter film material on the other horizontal surface, and a nearest vacuum source facing the other surface of the substrate base material. A shielding member disposed at a position, and an optical band-pass filter manufacturing device, comprising: performing evaporation from an evaporation source while rotating the substrate base material supported on the rotary pedestal; A step of forming a band-pass filter film having a required thickness gradient on a surface thereof, wherein the amount of band-pass filter material deposited is controlled by the shielding member. apparatus. 6. The light according to claim 1, wherein a film thickness monitor is disposed along a line extending from a rotation axis of the rotating pedestal. Equipment for manufacturing bandpass filters. 7. A rotating pedestal that rotates about a rotation axis and has a support surface on its lower surface for supporting a flat substrate base material, and a second surface of the substrate base material supported on one side by the support surface. A deposition source disposed below the rotating pedestal for depositing the bandpass filter film material, and a method of manufacturing an optical bandpass filter using the rotating pedestal. By performing evaporation from an evaporation source while rotating the substrate base material supported on the rotary pedestal, a band-pass filter film having a required thickness gradient is formed on the other surface of the substrate base material. A method for manufacturing an optical bandpass filter, comprising forming a film. 8. A rotating pedestal having a horizontal support surface for rotating about a vertical rotation axis and supporting a flat substrate base material on the lower surface thereof, and a substrate base material having one surface supported on the support surface. An evaporation source arranged below the rotating pedestal for evaporating the band-pass filter film material on the other horizontal surface, and a shielding member arranged at a position closest to the other surface of the substrate base material. A method of manufacturing an optical bandpass filter, comprising: performing vapor deposition from a vapor deposition source while rotating a substrate base material supported on the rotary pedestal, so that the other surface of the substrate base material has a required thickness gradient. A method of manufacturing an optical band-pass filter, comprising: controlling a deposition amount of a band-pass filter material by the shielding member when forming the formed band-pass filter film. 9. The method according to claim 8, wherein the shielding member has a rod shape or a plate shape. 10. A rotating pedestal that rotates about a rotation axis inclined at a predetermined angle with respect to a vertical line and has an inclined support surface on its lower surface for supporting a plate-shaped base material, and has one surface on the support surface. An evaporation source disposed below the rotating pedestal and at a position avoiding the extension of the rotating shaft for depositing the band-pass filter film material on the other inclined surface of the supported substrate preform; And a shielding member disposed at a position immediately adjacent to the other surface of the optical band-pass filter, wherein the vapor deposition is performed from a vapor deposition source while rotating a substrate base material supported on the rotating pedestal. According to the present invention, when a bandpass filter film having a required thickness gradient is formed on the other surface of the substrate base material, the amount of the bandpass filter material deposited is controlled by the shielding member. Optical bandpass Method of manufacturing a filter. 11. A rotating pedestal having a horizontal support surface that rotates about a vertical rotation axis and supports a flat substrate base material on its lower surface, and a substrate base material that is supported on one side by the support surface. A vapor deposition source disposed below the rotating pedestal and at a position avoiding the extension of the rotating shaft to vapor-deposit the band-pass filter film material on the other horizontal surface, and a nearest vacuum source facing the other surface of the substrate base material. A shielding member disposed at a position, and a method of manufacturing an optical band-pass filter using the substrate base material by rotating the substrate base material supported on the rotary pedestal while performing evaporation from a deposition source, A step of forming a band-pass filter film having a required thickness gradient on a surface thereof, wherein the amount of band-pass filter material deposited is controlled by the shielding member. Method. 12. The apparatus according to claim 7, wherein a film thickness monitor is arranged along a line extending an axis of rotation of the rotating pedestal. A method for manufacturing an optical bandpass filter.