JP2003140101A - Waveguide type optical element and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily mount a surface optical element made thin to have about 10 to 100 μm thickness on an optical device using an optical fiber or a waveguide as a transmission line without breaking the surface optical element. SOLUTION: A waveguide type optical element has a groove 11-2 formed so as to cut a light passage part, in a substrate having an optical waveguide or the optical fiber fixed and has a thin active surface optical element 11-4 which is practically perpendicularly inserted and fixed to the groove and is operated by voltage application and a support member 11-5 which is stuck to the surface optical element. The width W of the groove satisfies w<W<300 μm where w is the thickness of the surface optical element.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides an optical fiber and an optical waveguide with a planar element or material for controlling light intensity, phase and polarization, or a planar element or material having light receiving, emitting and modulating functions. The present invention relates to a mounted structure and a manufacturing method thereof. In particular, it relates to a technique for inserting a thin active surface-type optical element into a groove formed perpendicularly to a substrate provided with an optical fiber or an optical waveguide.

[0002]

2. Description of the Related Art Conventionally, many communication optical devices convert light from an optical fiber into collimated light, pass it through various surface-type optical elements (surface-type optical functional elements), and collect it again by a collimating lens. Then, it is coupled to the optical fiber and output to the output optical fiber. However, there are many problems such that the surface-type optical element becomes large and the cost is high.

23A to 23D show an optical device using a typical collimated fiber. In the figure,
19-1 is a fiber with an input collimator, 19-2 is a fiber with an output collimator, 19-3 is a rotating λ / 2 plate, 1
9-4 is a rotating λ / 4 plate, 19-5 is a rotating or moving type N
D filter, 19-6 is a homogeneous liquid crystal element, a TN liquid crystal element, a liquid crystal variable wavelength filter in which liquid crystal is contained in a Fabry-Perot interferometer, or a piezo control Fabry-Perot interferometer variable wavelength filter, 19-7 is a polarizer 1, 19 -8 is a polarizer 2 and 19-9 is a Faraday rotator.

Generally, in a polarization control element, by inserting a λ / 4 plate or a λ / 2 plate between collimating fibers and rotating them, an input polarized wave is infinitely followed by an arbitrary polarized wave. It can be controlled (see FIG. 23A). A manual type is often used in the laboratory, but a motor control type is used in a practical system. As a variable optical attenuator, a surface type ND filter is rotated for collimated light.
There is a mechanical variable attenuator that has been moved (see Figure 23B). This also has a manual type and a motor control type. Further, a phase modulator for inserting a homogeneously oriented liquid crystal plate between the collimating lenses and a polarized light for inserting a TN liquid crystal 0 ← → 9
There are a 0-degree polarization switching element, a liquid crystal variable optical filter in which liquid crystal is put in a Fabry-Perot type filter, and a variable wavelength filter that changes the Fabry-Perot type filter gap with a piezo (see FIG. 23C).

The optical isolator is composed of polarizers having different 45 ° directions between collimated lights and a Faraday rotator inserted between them (see FIG. 23D). A polarization separation element is inserted between them. Other optical fiber amplifiers use a spatial beam system to introduce pumping light into the optical fiber.

[0006]

However, in the above-mentioned prior art, there is a problem that the coupling and alignment of the light beam requires labor, the channel is a single channel, and the element becomes large, and the cost of the optical component is low. It has become a major bottleneck. By the way, if a groove of about 10 μm to 100 μm is dug in a substrate on which an optical waveguide or an optical fiber is fixed and the functional device is inserted into the groove, an optical device realized in a space system can be realized as a waveguide type. become.
Further, if the groove width is 10 μm to 100 μm, the loss of light due to the groove is smaller than that in the spatial beam system. In particular, a groove of 40 μm or less has a very low loss of 0.2 dB.

We have realized a variable optical attenuator by digging grooves and filling liquid crystal in a plate to which an optical waveguide and an optical fiber are fixed. Furthermore, in the optical waveguide,
A method is used in which a polyimide wave plate is inserted to eliminate polarization dependence, or a dielectric mirror formed on polyimide is inserted to separate wavelengths. Thus, it was relatively easy to insert a liquid or elastic material into the groove.

However, glass, semiconductors, electro-optic crystals,
When an individual planar optical device such as ceramics is thinned to a thickness of 10 μm to 50 μm and inserted, it is easily damaged and handling is very difficult. If the fine movement table is used for insertion, the planar optical device will be damaged even if the fine movement table is erroneously moved by 1 μm if the fine movement table is inserted.

When the method of forming the groove is etching such as RIE, the groove depth is 100 μm to 50 μm.
As shallow as m, in that case, even if a thin device is inserted,
There was a problem that it was not stable and the device collapsed. Further, even if a thin optical device having a thickness of about 10 μm to 50 μm is inserted, there is a problem that it is difficult to attach electrodes thereafter.

The object of the present invention is 10 μm to 100 μm.
It is an object of the present invention to provide a technique that can be easily mounted on an optical device using an optical fiber or a waveguide as a transmission path without damaging a planar optical element that is made thin to some extent. Another object of the present invention is to provide a technique capable of taking out an electrode at the same time if the surface-type optical element has an electrode. The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[0011]

Therefore, according to the present invention, a groove is formed in a substrate having an optical waveguide or an optical fiber fixed thereto so as to cut a light passage portion, and the groove is inserted substantially perpendicularly to the groove. Provided is a waveguide type optical element having a thin active surface-type optical element that is fixed by the above-mentioned and operates by applying a voltage, and a support member attached to the surface-type optical element.

Preferably, the width W of the groove is w <W <300 μm, where w is the thickness of the planar optical element. The support member may have an electrode for taking out the electrode of the surface-type optical element. Preferably, the support member is any one of a rectangular, L-shaped, and pillar-shaped block made of glass, ceramics, or plastic, and the height h and width I of the block and the block protruded from the block. The relationship between the lengths s of the surface-type optical elements is that when the surface-type optical element in which the supporting member is attached to the surface of the substrate on which the optical waveguide or the optical fiber is fixed is mounted, I / h> s / I is set in order to give a slight tilt to prevent the tilt.

When the block is a rectangular block, an L-shaped electrode is wired in one corner on the upper surface of the block, and the electrode of the planar optical element and the electrode of the laminated block are connected to each other. In some cases, the electrodes of the planar optical element are taken out from the upper surface side of the block.

As a typical example of the surface type optical element, a PbS photodetector is formed on glass, or a
-Si photodetector, photodetector with thinned semiconductor device, semiconductor optical modulator, polarizer in which fine metal particles are aligned in the long axis direction in glass, dispersed, optical crystal wavelength plate, dielectric multilayer film deposited on glass substrate Examples include a filter, an ND filter, a variable wavelength filter composed of an electro-optic crystal or electro-optic ceramic sandwiched by a dielectric multilayer mirror, and an electro-optic crystal / electro-optic ceramic polarization modulator.

When the surface type optical element is a liquid crystal element,
The support member is a pair of blocks attached so as to sandwich the liquid crystal element, and the liquid crystal element is a thin glass plate with electrodes patterned on one surface of each block facing each other, and on the thin substrate. You may make it have the alignment film which carried out alignment processing of rubbing etc. formed in 2 and the liquid crystal filled between both alignment films.

In this case, eight electrodes are radially formed on each glass plate of the liquid crystal element so as to be center-symmetrical, and light passes through the central portion of the radial electrode.
It has a window of 0 μmφ to 50 μmφ, and by adjusting the voltage applied to the eight electrodes, it is possible to adjust the voltage to 36 at the center.
It is possible to apply an electric field of an arbitrary intensity of 0 degrees and an arbitrary intensity, and when an arbitrary polarized wave is incident, it can be converted into an arbitrary polarized wave with infinite tracking.

Further, as an example, the surface-type optical element is a thin optical modulator, and the optical modulator includes a PLZT thin plate having four grooves cut from four side surfaces, and the PLZT.
Four electrodes formed from the four side surfaces of the thin plate to the inside of each groove cut, a conductive adhesive filling the cut grooves, and affixed to the PLZT thin plate, the four electrodes And a thin glass plate with four electrodes connected to each other, the thin glass plate with four electrodes is fixed to the support member so that light passes through the centers of the four electrodes, and the electrodes of the optical modulator are external. By adjusting the voltage applied to the four electrodes,
It has a function of converting the polarization of incident light into a linear polarization with infinite follow-up by applying an electric field of arbitrary intensity in any direction. In this case, it is desirable that the optical waveguide or the optical fiber fixed to the substrate has an expanded core in order to reduce loss.

The present invention also relates to the above waveguide type optical element, wherein a thin active type surface is formed on a substrate on which an optical waveguide or an optical fiber is fixed so that a groove is formed so as to cut a light passage portion, and which is activated by applying a voltage. A supporting member is attached to the mold optical element so that a part of the planar optical element protrudes, and the protruding portion of the planar optical element to which the supporting member is adhered is inserted into the groove substantially perpendicularly and fixed. A method for manufacturing a waveguide type optical element is provided.

As a preferred example, the surface type optical element is inserted into the groove so that the light passing portion of the surface type optical element inserted in the groove corresponds to the position of the core of the optical fiber or the optical waveguide. , A positioning mark is provided at a position where the distance from the portion through which the light passes to the core position is measured from the surface of the substrate, and when the planar optical element is bonded to the supporting member, this positioning mark And the bottom surface of the support member so that they are aligned with each other.

Further, as a preferred example, the supporting member is any one of a rectangular, L-shaped, and pillar-shaped block made of glass, ceramics, or plastic, and has a height h and a width I of the block. , The relationship of the length s of the planar optical element of the portion protruding from the block is I / h> s /
In the step of inserting the planar optical element into the groove, the planar optical element to which the supporting member is attached is placed on the surface of the substrate so that the planar optical element is slightly tilted so that the planar optical element does not fall down. The surface type optical element is dropped into the groove and fixed by sliding it toward the groove and moving it.

In the process of sliding the surface type optical element, both the supporting member and the end of the surface type optical element may be in contact with the surface of the substrate. Typically, in the process of dropping the surface-type optical element into the groove, the end of the surface-type optical element is bent by being caught in the groove, and the surface-type optical element is inserted into the groove. As a preferred example, when the planar optical element has an electrode and the block is a rectangular block, an L-shaped electrode is wired in one corner on the upper surface of the block, and the electrode is bonded to the electrode of the planar optical element. The step of connecting the electrodes of the formed block to the outside of the electrodes of the planar optical element from the upper surface side of the block.

According to the waveguide type optical element and the method for manufacturing the same of the present invention, (1) a polarization control element that always converts linear polarization even if an arbitrary polarization is input is used as an optical waveguide or an optical fiber. It can be formed on a fixed substrate. (2) High-speed phase modulation is possible and a high-speed waveguide optical switch can be realized. (3) A variable wavelength filter that can select only light of an arbitrary wavelength can be mounted on a substrate on which an optical waveguide or an optical fiber is fixed. (4) An optical attenuator can be realized on an optical fiber or an optical waveguide. (5) The intensity of passing light can be monitored. (6) In addition, all kinds of devices using the spatial beam can be mounted on the substrate on which the optical waveguide or the optical fiber is fixed, and the waveguide type optical element can be miniaturized.

Further, as described above, the inventor of the present invention slides the surface-type optical element on the substrate with tweezers in the process of dropping the surface-type optical element into the groove. It has been found that a thin surface-type optical element can be easily inserted into the groove by the edge being caught in the groove and the surface-type optical element naturally "falling" into the groove. When this method is used, the surface-type optical element is hardly damaged because it is applied with almost no unreasonable force.

Further, as described above, before the groove is inserted, an alignment mark is attached to the surface type optical element at a position where the distance from the portion through which the light passes to the core position from the surface of the substrate is measured. This has the advantage that the waveguide core and the window of the surface-type optical element coincide with each other when they are dropped into the groove. Usually, when the surface-type optical element is inserted into a narrow groove by using a fine movement table or the like, extra force is often applied and the surface-type optical element is often damaged.

When the surface-type optical element is attached to the supporting member such as the block as described above, it has a reinforcing effect and a process such as photo-machining can be added to the whole surface-type optical element later. Furthermore, in the case of a liquid crystal element, it is possible to apply an alignment film or rub it. Further, if the thin surface type chip is attached to the glass with a thin electrode and further attached to the block, it is possible to take out a complicated electric wiring electrode of the surface type chip.

Japanese Unexamined Patent Publication No. 9-297229, "Method for manufacturing a filter type waveguide," discloses a mode in which a filter having a block bonded thereto is inserted into a groove that traverses a waveguide element. However, this filter is a passive element such as a wave plate and is therefore not an active surface optic with electrodes.
Moreover, the block to be attached is provided for the purpose of correcting the warp of the filter and aligning the groove with the filter rather than the "supporting member". Even if a marker is not used, it is not provided for the purpose of easily inserting the surface type optical element by bending the edge of the surface type optical element by being caught in the groove.

Also, Shojiro Kawakami et al. “Vertical Photonics” (Journal of the Institute of Electronics, Information and Communication Engineers CI, Vol. J77-CI,
No. 5, pp. 334-339, 1994) discloses an example in which a liquid crystal element is inserted across an optical fiber array on a substrate. However, in this example, the element has a thickness of 600 μm or more, and therefore, there is no concept of providing a support block, and its purpose, structure, and action are different from those of the present invention.

[0028]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below in detail with reference to the drawings.
FIG. 1A is a diagram for explaining a schematic configuration of an optical waveguide substrate or an optical fiber substrate according to a second embodiment of the present invention and a manufacturing process thereof. FIG. 1A is a perspective view of the optical waveguide substrate.
(B) is a figure for demonstrating the manufacturing process of an optical fiber fixing plate. 2A to 2B are views for explaining the groove forming process of the present embodiment, FIG. 2A is a view showing a groove forming process by etching, and FIG. 2B is a dicing saw. It is a figure which shows the groove formation process by. FIG. 3 (A)-
FIG. 3D is a diagram for explaining a schematic configuration of the surface-type optical element according to the embodiment of the present invention and its fabrication. FIG. 3A is a L-shaped support member when the support member is a round bar. For blocks,
FIG. 3C shows the case of a support plate, and FIG. 3D shows the case of a rectangular block.

In FIGS. 1A to 3D, 11
-1-1-1 is an optical waveguide substrate, 11-1-1A is a substrate to which an optical fiber is fixed (hereinafter referred to as an optical fiber substrate), 11-
1-2 is a glass plate that holds the optical fiber from above, 11-1
-3 is a bare fiber, 11-1-4 is a (UV) coating of the optical fiber, 11-1-5 is a V-groove array for fixing the optical fiber, and 11-1-6 is an adhesive. is there. 11-2
Is a groove which is provided vertically or almost vertically so as to cut the photoconductive portion of these plates. The groove 11-2 may be formed by etching as shown in FIG.
You may dig by dicing as shown in (B).

Further, referring to FIG. 6, 11-3 is a dicing plate, 11-4 is a thin surface-type optical element (optical functional element), 11-5 is a supporting member made of glass, ceramics, plastic, etc. Called block), 11-6
Is an adhesive for adhering the block to the planar device, 11-
7 is an alignment mark between the block and the optical device, 11-
8 is a window through which the light of the planar optical element passes, 11-9 is an electrode of the optical device, 11-10 is a pattern electrode attached to the block in an L-shape, 11-11 is an optical waveguide substrate and the planar optical element. An adhesive having a matching refractive index, 11-12 is a take-out electrode, and 11-13 is vacuum tweezers. The pattern electrode 11-10 of the block 11-5 may be formed by vapor-depositing metal on two L-shaped surfaces and then patterning the two surfaces by photomachining or mechanically cutting by dicing or the like. .

The optical fiber core wire 11-1-3 is placed on the V-groove array 11-1-5, and the glass plate 1-1-2 is filled with the pressing adhesive 11-1-6. Fiber substrate 11
-1-1A is manufactured (FIG. 1B). The mounted optical waveguide substrate of the surface-type optical device of the present embodiment has a structure as shown in FIGS.
As shown in (1), a groove having a width of about 10 μm to 300 μm and a depth of about 100 μm to 500 μm is formed (digged) on the optical waveguide substrate 11-1-1 or the optical fiber substrate 11-1-1A. The optical waveguide substrate 11-1-1 is a glass waveguide, si
Either a waveguide on a substrate or a polymer waveguide may be used.

As shown in FIG. 1B, the optical fiber substrate is provided with a V-groove array 11-1-5 on which a coated optical fiber core 11-1-3 is placed, and further on the core fiber 11-1-3. A thin glass plate 11-1-2 may be arranged on the inner surface and fixed with an adhesive 11-1-6, or an optical fiber may be fixed with a resin. When a thin surface-type optical element is inserted into this, a glass block is adhered and "dropped" into the groove. As shown in FIGS. 1 (A) and 1 (B), an optical waveguide substrate 11-1-1 or an optical fiber substrate 11-1-
As shown in FIGS. 2A to 2B, a groove is formed in 1A by etching (FIG. 2A) or dicing (FIG. 2B).

With the current dicing plate, it is possible to form (dig) a groove of about 15 μm to 400 μm while polishing it flat. Several μ in case of etching
While it is possible to dig a groove with a width of m, the former dicing method is capable of digging relatively wide and deep, while the latter etching method is suitable for digging a relatively narrow and shallow groove. There is.

Next, as shown in FIGS. 3 (A) to 3 (D),
A thin surface type optical element 11-4 for insertion is prepared. Normal,
The thin surface-type optical element 11-4 is manufactured by stacking electrode processing, epitaxy, etc., and then polishing it to a thickness of 10 μm to 100 μm.
It is thinned to about m and cut into several mm squares. If the thickness is about 100 μm, it can be inserted into the groove with tweezers, but a thinner surface-type optical element 11-4 than that can be inserted into the groove 1.
It is very difficult to insert it into 1-2.

In this embodiment, as shown in FIGS. 3A to 3D, the thin surface type optical element 11-4 is replaced with an optical waveguide substrate 11-1-1 or an optical fiber substrate 11-1-1A. In order to stabilize the surface type optical element 1-4 when it is mounted on the surface, the surface type optical element 1-4 is slightly tilted and supported by various blocks. For example, as shown in FIG. 3 (A), a round bar 11-5-
1 is attached to the surface-type optical element 11-4 so that the surface-type optical element 1-4 does not fall.

Further, as shown in FIG. 3B, an L-shaped block 11-5-2 is attached, or as shown in FIG. 3C, a support plate 11-5-3 is attached vertically, Alternatively, as shown in FIG. 3D, a rectangular block 11-5-4
The optical waveguide substrate 11-1-1 or the optical fiber substrate 11- so that the planar optical element 11-4 does not fall over.
Place on the surface of 1-1A. At this time, in the case where a window for transmitting light is formed in the surface-type optical element 11-4, FIG.
(B) (FIG. 4 (A) is a perspective view, FIG. 4 (B) is a front view)
As shown in FIG. 5, the depth from the surface of the substrate to the core is measured in advance, and the light transmitting portion 11-8 is bonded so as to protrude from the glass block corresponding to this depth.

± 5μ if alignment mark is attached
It can be bonded with an accuracy of about m. Surface type optical element 11-4
If an electrode is provided on the surface type optical element 11-
No. 4 electrode and the electrode (pattern electrode) 11-10 of the block 11-5 are connected to each other, and the L-shaped electrode provided at the corner of the block 11-5 leads to the upper side of the block 11-5. Since it may be difficult to separate the electrodes 11-10 at the L-shaped portion by ordinary photo-machining, they may be mechanically cut by dicing.

When the block 11-5 is not provided, it is necessary to take out the electrode directly from the thin surface type optical element 11-4, but when the electrode 11-10 is attached, the surface type optical element 11-4 is provided.
There was a problem that was damaged. When the block 11-5 is provided, if the thin portion protruding from the glass block 11-5 is not touched, the portion of the block 11-5 can be grasped and handled by using ordinary tweezers. Therefore, it becomes possible to apply an alignment film for liquid crystal to the surface type optical element 11-4 on the block 11-5 with a spinner or mechanically rub it.

Next, as shown in FIG. 5A, the thin surface type optical element 11-4 attached to the block 11-5 is attached to the optical waveguide substrate 11-1-1 or the optical fiber substrate 11-1-.
Place on the surface of 1A. At this time, the block 11-5
Of the height h and width I of the block 11-5 and the length s of the surface-type optical element 11-4 protruding from the block 11-5 is I / h.
When> s / I, the block 11-5 tilts in a stable state without tilting, and the surface-type optical element 11-4 is the surface of the optical waveguide substrate 11-1-1 or the optical fiber substrate 11-1-1A. It is placed so that it touches.

If the width I of the block 11-5 is thin, the block 11-5 collapses as shown in FIG. 5 (B), and the surface-type optical element 11-4 becomes the optical waveguide substrate 1.
It becomes impossible to contact the surface of 1-1-1 or the optical fiber substrate 11-1-1A. Thus, the surface-type optical element 1
1-4 is in contact with the surface of the optical waveguide substrate 11-1-1 or the optical fiber substrate 11-1-1A, and the optical waveguide substrate 11-1-1 or the optical fiber substrate 11-1-1A is tweezers or the like. Slowly push on the surface.

Here, the surface of the optical waveguide substrate is usually a mirror surface, and the substrate on which the optical fiber is fixed is also flat as a mirror surface because the cover glass is placed on the fiber. Therefore, the surface-type optical element 11-4 is not applied with an excessive force and slides sideways without being damaged. Thin surface type optical element 11
When -4 reaches the position of the groove 11-2, as shown in FIG. 5C, the edge of the surface-type optical element 11-4 hits the groove 11-2,
It will bend and will naturally fall into the groove 11-2.

If the portion to be inserted into this groove is thick, it will not bend and therefore will not fall into the groove, but as in this embodiment, it will bend if it has a thickness of about 10 μm to 100 μm, or up to about 150 μm. It can be inserted very easily. The block 11 for aligning the optical waveguide core of the optical waveguide substrate 11-1-1 or the optical fiber substrate 11-1-1A with the window of the planar optical element.
-5 is moved back and forth on the paper to align the optical waveguide substrate 11-1-1 or the optical fiber substrate 11-1-1A.
Then, the surface type optical element 11-4 is fixed with an optical adhesive 11-11 having a refractive index matched with the surface type optical element 11-4.

In this way, as shown in FIG. 6, the optical waveguide substrate 11-1-1 or the optical fiber substrate 11- is used.
The surface-type optical element 11-4 can be mounted vertically or almost vertically in the groove 11-2 of 1-1A. It should be noted that using a conventional fine movement table requires a great deal of labor for alignment,
There is a problem that even if the surface-type optical element 11-4 is accidentally bumped into the groove 11-2, the surface-type optical element 11-4 is damaged.

In the above description, one surface type optical element 11 is used.
Although the case of inserting -4 has been described, the same applies to the case of inserting two surface type optical elements 11-4 in the same groove as shown in FIG. 7 (A). In the case of a liquid crystal element (details of which will be described later) in which a liquid crystal 201 is filled in a thin glass substrate 202 to which a glass block 203 is attached as shown in FIG. 7B, one glass plate 202 is Figure 7
As shown in (C), it is caught in the groove, bends, and falls into the groove (FIG. 7D).

It is usually difficult to insert a substrate having a width substantially equal to the groove width. For example, when inserting a planar element from above using a fine movement table, be very careful not to hit the groove wall surface. You will need it. According to this embodiment, it is possible to insert a surface-type element having a thickness that substantially matches the groove width into the groove.

That is, according to the present embodiment, it becomes possible to reduce the thickness of an optical device which has been conventionally realized only in bulk and insert it into the optical waveguide groove, and various optical functional devices can be used as an optical fiber and an optical waveguide. Hybrid implementation is possible easily. In the following embodiments, the support member is described by the term block, but the term block is used in the sense of including all shapes such as a rod, a plate, and an L-shaped block, rather than a rectangular block.

Example 1 In Example 1 of the present embodiment,
It is intended to provide a method for manufacturing an element (polarization controller) for converting an arbitrary polarized wave into a polarized wave in an arbitrary direction by inserting a polarization control element into an optical waveguide. The polarization controller is used for polarization dispersion compensation in an actual system.

Prof. Kawakami of Tohoku University
As shown in (C), a vertical alignment film is applied to glass having electrodes with eight electrodes symmetrically arranged about the center, and a liquid crystal is filled to p.
Type nematic liquid crystal is filled to make it homeotropic, and the phase of the voltage applied to the 8 electrodes is adjusted so that a linear electric field is applied to the central part and its direction is set to an arbitrary angle of 360 degrees. , The phase amount of the rotating wave plate is adjusted by adjusting the strength of the electric field (see: Shojiro Kawakami et al., "Polarization control using liquid crystal", IEICE Technical Report, OME95-49, OPE95). -90, pp. 19-24, 1995
Year).

In FIGS. 8A to 8C, 12-1 is a window through which light at the center of 8 electrodes passes, 12-2 is 8 symmetrical electrodes, 12-3 is a glass substrate, and 12-4 is 12-4. Vertically aligned liquid crystal, 12-5 is a light beam that has passed through the central window of 8 electrodes, and 12-6 is a state in which the liquid crystal molecules are rotated by applying the voltage applied to the 8 electrodes by changing the phase. It is a thing. The diameter of the part through which light passes is about 50 μm, and λ
/ 2, λ / 4 plate corresponding to two liquid crystal rotation wave plates, voltage is applied and the angles θ ₁ and θ ₂ of the axes of the two liquid crystals are adjusted, so that the light passing therethrough We have succeeded in always converting the polarization of the beam to linear polarization.

Since the liquid crystal rotary plate is composed of a glass plate having a thickness of several mm, it is usually made into a device by using a spatial beam. In the first embodiment, the liquid crystal rotating plate is inserted into the optical waveguide substrate or the optical fiber substrate. Figure 9
10A to 10C are views for explaining a manufacturing process of the liquid crystal rotation wavelength plate of the first embodiment. In FIGS. 9A to 10C, 13-1 is a centrally symmetric 8-electrode pattern, and a window having a diameter of 20-50 μm is formed. 13-2 is a glass substrate having a thickness of 0.5 mm or more, 1
3-3 is thinned to 15 μm or less by polishing,
Glass substrate cut into corners, 13-4 is a glass block, 13-5 is a spacer, 13-6 is a nematic liquid crystal, 1
Reference numeral 3-7 is a glass polarizer having a thickness of 30 μm, and 13-8 is a transmissive detector.

As shown in FIG. 9 (A), a metal electrode is vapor-deposited on a glass plate having a thickness of about 1 mm, and then eight centrally symmetric electrodes are formed by photomachining to have a window diameter of about 20 to 50 μm.
To form. When forming an array, the same pattern may be formed in an array. There are various methods for taking out the electrodes, and detailed description thereof will be omitted. As shown in FIG. 9B, the back surface of the glass plate is polished to 10 to 15 μm.
Thin. The thin glass plate is cut by dicing.

As shown in FIG. 10 (A), a glass substrate 13-4 with 8 electrodes (13-1) thinly cut with vacuum tweezers is placed on a glass block 13-4 and irradiated with ultraviolet rays. , Glue. A pair of glass blocks to which the glass substrate with 8 electrodes is adhered are produced, and an alignment film (for vertical alignment) is applied on each spinner in blocks, dried and heat-cured to form an alignment film. Usually, polyimide is used for the alignment film, but since an adhesive has already been used here, it is heat-cured with a polyimide for low temperature curing (180 ° C. curing).

Next, as shown in FIG.
pasted together with a spacer 13-5 having a thickness of about m,
As shown in FIG. 10C, the vertically aligned nematic liquid crystal 1
A liquid crystal element is manufactured by filling 3-6. At that time, it is necessary to perform alignment so that the window portions through which the light passes match. Although it is usually impossible to fabricate a liquid crystal cell of a few mm square as described above with a glass substrate having a thickness of 15 μm, by using the glass block 13-4 as in the process of the first embodiment, It can be made into an element. The prepared liquid crystal element is filled with p nematic liquid crystal to form a homeotropic liquid crystal element.

FIG. 11 is a diagram for explaining a method of manufacturing an infinite tracking polarization control element using the liquid crystal rotating wavelength plate of the first embodiment and a method of mounting it on an optical waveguide substrate. As shown in FIG. 11, the method for producing an infinite tracking polarization control element using the liquid crystal rotating wave plate of the first embodiment is applied to an optical waveguide substrate with about 7 layers.
One groove of 0 μm and another groove of about 40 μm are formed in a cascade by dicing. On the waveguide surface near the groove of 70 μm width, place the rotating wave plate attached to the fabricated block by tilting it slightly so that it does not fall, slide it sideways, and “drop” the protruding part of the liquid crystal rotating wave plate into the groove. ".

Next, the light is passed through the optical waveguide, the block is moved back and forth on the paper surface so that the light enters the window of the liquid crystal, the block is aligned, the adhesive is poured, and the resin is ultraviolet-cured and fixed by adhesion. Further, a glass polarizer 13-7 (30 μm thick) formed in the same manner is inserted in the second groove so that only linearly polarized light passes through. Glass polarizer 13-7
Is formed by dispersing silver metal fine particles in the glass and stretching the glass at a high temperature so that the silver fine particles are aligned in the long axis direction, and usually has a thickness of about 1 mm. . The minimum thickness on the market is 30 μm,
By inserting into a groove formed in the optical waveguide substrate or the optical fiber substrate, it is possible to pass a linearly polarized wave having a polarization extinction ratio of 30 dB or more. Usually, a glass polarizer having a thickness of 30 μm is difficult to handle.

According to the first embodiment, the infinite tracking polarization control element can be inserted by digging a groove at a desired position on the optical fiber substrate and the optical waveguide substrate. A PbS light transmissive detector 13-8 formed on a glass substrate can be inserted into the third groove to serve as a light power monitor. The photodetector may be an ordinary photodetector such as InP polished to a thickness of about 15 μm. The voltage applied to the 8 electrodes × 2 electrodes of the liquid crystal determines the direction of the electric field applied to the center θ
And the voltage V ₀ determined by two parameters of the electric field strength E
Any polarized wave is converted into a straight line by the two parameters of.

These two parameters are adjusted so that the light power passing through the polarizer is always maximized, and the polarization control element is controlled so that the light passing through the polarizer is always maximized. By doing so, polarized waves that are perpendicular or parallel to the waveguide are always input to the waveguide, and it is not necessary to consider the polarization dependence of the waveguide, so that the waveguide function is greatly improved. It is highly functional. For example, the optical waveguide type optical switch has polarization dependence, which is solved,
The optical attenuator has a polarization dependence of about 3 dB, which is also eliminated. The AWG filter has poor wavelength selectivity due to the polarization dependence, but this problem is solved. Further, the SOA placed on the waveguide does not need to be polarization independent. The above polarization control technology can also be applied to polarization dispersion compensation.

Example 2 Example 2 of the present embodiment is a method of manufacturing a liquid crystal plate for controlling polarization by inserting a parallel alignment liquid crystal plate and a twisted nematic liquid crystal plate. In the first embodiment, the polarization control element is realized by the liquid crystal rotation wavelength plate having eight electrodes. However, two ordinary parallel alignment liquid crystal plates are arranged at angles of 0 degree and 45 degrees and arranged in a cascade. Polarization control is also possible. Further, by inserting a twisted nematic liquid crystal, it is possible to convert the polarized wave TM wave ← → TE wave of the waveguide.

12 (A) to 13 (C) are views for explaining a manufacturing process of the parallel alignment liquid crystal plate of Example 2.
14-1 is a stripe transparent electrode (ITO) patterned at the same pitch as the waveguide pitch, and 14-2 is 0.5
Glass substrate with a thickness of mm or more, 14-3 is a glass substrate 1
4-2 is a glass substrate thinly polished to 15 μm or less, 14-4 is a glass block, 14-5-1 is a spacer, 14-5-2 is an alignment film, 14-5-3 is a liquid crystal, 14-
6 is a core, 14-7 is a parallel-aligned nematic element oriented in the direction of 0 degree, 14-8 is a parallel-aligned nematic element oriented in the direction of 45 degrees, 14-9 is a glass polarizer, 14-10 is a transmission type It is an optical detector.

A liquid crystal element was prepared in the same manner as in Example 1,
When two liquid crystal elements having an alignment direction parallel to the waveguide and inclined by 45 are prepared and a large nematic liquid crystal having a Δn of about 0.25 is filled in a cell gap of about 20 μm, 4 μ is obtained.
Since the optical length of m to 5 μm can be adjusted, the phase can be adjusted to 0
It can be adjusted by about 6π. When infinite polarization control is possible, additional polarization control is possible by adding another liquid crystal plate and resetting the total of three liquid crystal plates.

As shown in FIG. 12A, a glass substrate (14-2) with a stripe transparent electrode (14-1) is prepared in the process of the method for producing a parallel alignment liquid crystal plate of the second embodiment. Glass substrate with stripe transparent electrode (14-1) (1
4-2), as shown in FIG.
Grind to a thickness of m and cut. Next, as shown in FIG. 12C, a glass block 14-4 is attached to the thinly polished glass substrate 14-3, and an alignment film 14-5-2 is provided on the opposite surface.
Apply. Four such glass substrates are prepared, and two glass substrates are rubbed in the directions of 0 ° and 45 °, respectively.

Next, as shown in FIG. 13A, liquid crystal 14-5-3 is filled with 0 ° orientation bonded to each other (a1) and 45 ° orientation bonded to each other (a2). Next, FIG.
As shown in (B), the transparent stripe electrode is aligned with the portion through which light is inserted by inserting it into the optical waveguide. This alignment moves the block so that light passes through. This is easy because it is a uniaxial alignment.
Next, as shown in FIG. 13C, a parallel alignment nematic element (liquid crystal plate) 14-7 oriented in the direction of 0 degrees and a parallel alignment nematic element (liquid crystal plate) 14-oriented in the direction of 45 degrees.
8 and then a glass polarizer 14-9 and a transmissive photodetector 14-10.

In FIG. 12 (A) to FIG. 13 (C), the liquid crystal element was manufactured and then inserted into the groove. However, instead of inserting the liquid crystal cell, one sheet of alignment film / thin glass with a transparent electrode was inserted into the groove. Insert the ITO and attach the ITO and the alignment film to the opposite wall,
It is also possible to fabricate an element for controlling polarization by inserting a liquid crystal therebetween. When this method is used, the groove width can be narrowed by the thickness of one glass substrate 14-3, which is advantageous in that loss can be reduced. In order to reduce the loss by making the glass plate as thin as possible, a glass plate having a thickness of 10 μm was used here.

The manufacturing process is shown in FIGS.
It shows in (D). In these figures, 15-1 is a transparent electrode formed on the wall surface of the waveguide groove, 15-2 is an alignment film,
15-3 is a rubbing roll, 15-4 is a glass block,
15-5 is a glass block, 15-6 is a 0-degree homogeneous liquid crystal, 15-7 is a twisted nematic liquid crystal, 15-8.
Is a glass polarizer, and 15-9 is a transmissive detector.
14 (A) to (C) are the same as those in FIG. 12 (A) to FIG.
It is similar to (C). However, rubbing is performed so that the rubbing directions are parallel orientation and 90-degree twist orientation.

In FIG. 15A, a transparent electrode is formed on the wall surface of the waveguide groove by sputtering, and an alignment film is applied thereon. In FIG. 15 (B), the rubbing is applied to the groove with the thinnest bristles having a diameter of 15 μm or less. This causes rubbing in the groove in the direction of 0 degree. Alternatively, rubbing can be performed by inserting a film thinner than the groove width and moving the film in a certain direction so as to scrape the groove wall surface. Next, FIG. 15 (C)
Then, the glass plates of 0 degree orientation and 90 orientation formed in FIG. 14C are inserted into the groove and bonded so as to be in close contact with the groove surface.

Further, on one side, an alignment film and a rubbing-treated glass block are placed so as to be flush with the groove side surface. The cell gap is usually estimated by the spacer used, but here, the cell gap d is obtained by microscopic observation of a cross section or interference measurement. From this, the optimum Δn of twisted nematic orientation can be found by the following equation. u = 2dΔn / λ, u = √3, √5, √35, √63
・ ・

A twisted nematic polarization control element having a higher polarization extinction ratio can be realized by filling a liquid crystal having Δn corresponding to this. That is, when a voltage of several V is applied, the light passing through this portion passes without changing the polarization. Next, when no voltage is applied, linearly polarized waves parallel to the waveguide are converted to vertical, and vertical polarized waves are converted to parallel. This operation is maintained even if the temperature changes. In this way, a polarization control device can be realized.

Example 3 Example 3 of the present invention is an example in which this embodiment is applied to a PLZT modulator. The PLZT optical shutter array is currently put into practical use as a high-speed commercial photo printer. PLZT is PbO, La ₂ O ₃ , Z
It is formed by mixing and sintering four oxides of rO ₂ and TiO ₂ , and is represented by the chemical formula of (Pb _1-x La _x ) (Zr _y Ti _z ) _1-x O ₃ and has a normal ( The value of x, y, z) is (9
/ 65/35) is known as a material having the optimum electro-optical effect. PLZT is 1 more than LN (Lithium Niobate)
It shows an electro-optic effect that is orders of magnitude larger.

The structures of typical commercially available optical shutter arrays are shown in FIGS. 16 (A) to 16 (C). FIG.
16A is a perspective view, FIG. 16B is a front view, and FIG.
Is a side view. In FIGS. 16A to 16C, 16
-1 is a PLZT ceramics substrate, 16-2 is a convex type, electrodes are formed on both sides of the shutter part to modulate the passing light beam, 16-3 is an electrode sandwiching the convex part PLZT, 16- 4 is a part where the electrodes are separated by dicing, and the two light beams 16-10 are incident from the lower side,
Exit to the top.

The electrodes are provided at intervals of 50 μm so as to be sandwiched between the left and right sides, and are controlled by a half-wave voltage of 50V. The surface of this shutter is 50 μm by dicing to form an array.
The electrodes are separated into pitches. Thus, by dicing, it is possible to form a shape with a unit of several tens of μm.
17A and 17B are PLs of Example 3 of the present embodiment.
It is a figure for demonstrating the manufacturing process of a ZT modulator. In these figures, 17-1 is an electrode attached to the side surface of a convex PLZT block, 17-2 is a convex PLZT, 1
7-3 is a slicing dicing surface, 17-4 is a convex PLZT chip polished after dicing, 17-5 is a glass block with electrodes, 17-6 is a conductive paste, 17-7 is an electrode attached to the glass block, 17- Reference numeral 8 is a waveguide provided with a groove, and 17-9 is an adhesive.

As shown in FIG. 17A, the convex PLZT
A block is prepared, and an electrode is formed on its side surface. Although an Al electrode may be used here, Cr having good adhesion is vapor-deposited in consideration of polishing. Width of convex part 17-30 is 30
~ 50μm, height 17-11 is 100-200μ
m. Next, as shown in FIG. 17 (B), slicing is performed by dicing to a thickness of 100 μm to 50 μm, and as shown in FIG. 17 (C), 30 μm to 50 μm.
To the thickness of.

Next, as shown in FIG. 17D, the modulator is adhered to a glass block having an electrode so that the modulator protrudes. What is adhered in parallel as shown in FIG.
As shown in (E), two types are prepared that are bonded at an angle of 45 degrees. The electrodes are taken out with solder or silver paste. Next, as shown in FIG.
A groove having a width of about m is formed in the waveguide, and the groove shown in FIG.
The block with the PLZT chip manufactured in the step (E) is slightly tilted and placed so as not to fall. The surface of the optical waveguide substrate or the optical fiber substrate is slid and inserted into the waveguide groove. In the step of FIG. 18B, the waveguide core is aligned in the front and rear of the paper so that the modulation portion and the modulation portion are aligned with each other, and the waveguide core is bonded with an adhesive having a matching refractive index. When a voltage of about 100 V is applied, π modulation becomes possible.

When two PLZT modulators arranged at 0 degree and 45 degrees are arranged in a cascade in two stages, when an arbitrary polarized wave is incident, it can be converted into a linear polarized wave. The response speed of PLZT is fast, and a response speed of 10 ns can be expected. The PLZT
Is a two-electrode type, and in order to control the polarization, it was necessary to insert two elements inclined at 0 ° and 45 °. In addition, in order to perform infinite polarization tracking, an additional two-stage PL
A ZT modulator is needed. PLZT that can make this one
The structure of the modulator is shown in FIGS.

FIGS. 19A and 19B are views for explaining a manufacturing process of a PLZT modulator of a modified example of the third embodiment, and 17-10 is a PLZT square bar in which grooves are formed from the left, right, top and bottom. , 17-11 are portions of a PLZT window through which light passes, an electrode 17-13 is formed next to the window, and an adhesive 17-14 is poured for reinforcement. Reference numeral 17-15 is a thin plate glass of about 15 μm, 17-16 is an electrode pattern formed thereon, and 17-17 is a glass block.

The PLZT modulator of the third embodiment is shown in FIG.
As shown in (A) to (B), a portion through which light passes (in the figure, arrow A indicates the incident direction of light),
Four electrodes 17-13 are formed. 500 x 10
Insert a square rod of 00 μm square into the dicing groove from the top, bottom, left and right,
About 50 to 100 μm where light passes is left. next,
The electrodes 17-13 are formed on the side surfaces of the T-shaped groove of PLZT by sputtering. For reinforcement, a conductive adhesive 17-14 is poured into the diced portion. The PLZT rod is sliced, cut and polished to a thickness of about 120 μm. This is thin glass with electrodes 17-15
Then, the electrode 17-13 and the conductive adhesive 17-14 are attached to the electrode 17-16 with the silver paste 17-20, and the glass block 17-17 is attached. FIG.
Similar to (A) and (B), this is inserted into the groove of the waveguide (in the figure, arrow B indicates the insertion direction). 4 electrodes 17-
By controlling the voltage applied to 13, it is possible to change the phase and its direction, and infinite polarization tracking is possible with this single element.

(Embodiment 4) When a polyimide wavelength plate having a thickness of 15 μm is inserted into a normal optical waveguide, a groove having a width of 20 μm and a width of about 200 μm is formed by dicing, and the groove is inserted with tweezers. Since polyimide is soft, it will not crack even if it is handled with tweezers. However, in order to reduce the loss of light, reactive etching such as RIE is used. When digging a groove by RIE, the depth is usually 50 to 10
The limit is to dig a groove of about 0 μm. Even when a thin wave plate made of polyimide or the like having a thickness of 15 μm is inserted into a groove having a width of 20 μm and a search of 50 μm, there is a problem that the polyimide film falls down because it is too shallow.

20A to 20D are views for explaining the step of inserting a polyimide wave plate by RIE, in which 18-1 is an optical waveguide and 18-2 is formed by RIE etching. Groove, 18-3 is polyimide film,
18-4 is a glass block, 18-5 is an adhesive, 18-6
Is an adhesive with matching refractive index. As shown in these figures, a groove having a width of 20 μm and a depth of 50 μm is formed by RI.
Formed of E, and laminated with a polyimide film on a glass block as shown in the above example, about 40 μm
By sticking them so that they stick out and dropping them into the groove, it becomes possible to insert the surface-type film into the narrow and shallow groove.

(Embodiment 5) In this embodiment, it is possible to realize a transmissive detector. In optical communication systems, it is necessary to constantly monitor the power in optical fibers and waveguides. Currently, a splitter or coupler separates a part of the light and monitors it with a detector. However, these require a large device. In order to monitor the power of the optical fiber and the light, it suffices to dig a small groove of about 15 μm to 30 μm and insert a transmissive detector between them.

This may be a polished single crystal detector of InGaAs or Ge which is usually used as a detector, or a PbS film or PbSe on a glass substrate.
The film may be formed by providing a window for passing light. For example, a PbS thin film is formed on a glass substrate, and a hole having a diameter of 10 μm through which light passes is formed by photomachining. At this time, an alignment mark is formed at a position corresponding to the search for the waveguide core through the hole through which the light passes.

The glass plate on which PbS is formed is ground to a thickness of 10 μm to 15 μm, cut into chips, and attached to a glass block. At this time, the alignment mark is aligned with the lower surface of the glass block. When it is inserted into the groove, the through hole of PbS and the core are aligned with each other. Therefore, the light is slightly shifted in the groove direction so that the light passes through the window of PbS and fixed. The light passing through the groove is slightly larger than the size of the core.
S can be converted into electricity, and the power of the light in the fiber or waveguide can be monitored without branching.

Example 6 In this embodiment, a thin polarizer can be inserted in the waveguide. A cube-shaped polarization beam splitter is often used for a polarizer having a high polarization extinction ratio. The planar polarizer obtained by stretching the polymer has a thickness of several 100 μm and has a low polarization extinction ratio. Dispersing silver particles in glass, developed by Corning,
The polarizer produced by melt drawing is glass, and the thickness thereof is 30 μm to several hundreds μm, and even if the thickness is 30 μm, the polarization extinction ratio guarantees 30 dB or more.

However, since a thickness of 30 μm is difficult to handle, a glass having glass on both sides and reinforced is commercially available. Here, a polarizer with a thickness of 30 μm and a size of several mm is s: 40.
2 mm (I) x 2 mm, protruding to about 0 μm
It was attached to the glass block of (h) and inserted into a groove of about 40 μm width provided in the waveguide or the fiber fixing plate. Here, since the condition I / h> s / I that the block does not fall is satisfied, it was possible to drop the block into the waveguide groove while keeping it slightly tilted and stably held so as not to fall. It was possible to obtain a linearly polarized wave of 30 dB in the waveguide.

Example 7 PLZT of FIGS. 19A and 19B
When the thickness of the chip is about 120 μm and the width of the groove to be inserted is about 150 μm, the optical power loss increases to 2.5 dB due to the diffraction loss of light in the groove, and the half-wave voltage increases to 130 V. . A configuration for eliminating this drawback will be described with reference to FIGS. 21 (A) to 22 (B). The core of an ordinary optical fiber is about 10 μm,
A core expansion fiber obtained by thickening this core by heat treatment is prepared. This is TEC (thermally expanded core fi
21B. As shown in FIG. 21A, a part 103 of the core of the optical fiber is enlarged in the optical fiber core fiber (bare fiber) 101 and the coating 102.

Such a TEC fiber is shown in FIG.
The fiber splicer 105 shown in (B) is inserted from both sides and a groove 107 of about 300 μm is formed by dicing (FIG. 21C). Next, the PLZT chip 109 polished to a thickness of about 280 μm is mounted on a glass substrate 110 having a thickness of about 15 μm, attached to a glass block 112, and the glass substrate 110 attached with the PLZT chip 109 is inserted into the groove (see FIG. 22 (A): Code 11
1 indicates an electrode). The PLZT chip is aligned so that the light passes through the center of the window and then fixed (see FIG. 22).
(B)). Since TEC fiber is used, the groove width is 3
Even if it is 00 μm, the loss is 1 dB or less, and the half-wave voltage is as low as about 50V. In addition, the above-mentioned configuration is a V that can install and fix a fiber instead of the fiber splicer
It may be realized by providing a groove on the substrate.

The inventions made by the present inventors are as follows.
Although specifically described based on the above embodiment, the present invention is
It is needless to say that the present invention is not limited to the above embodiment, and various changes can be made without departing from the scope of the invention.

[0086]

As described above, according to the present invention,
It is possible to easily insert a thin active surface-type optical element into a groove formed in a substrate having an optical waveguide or an optical fiber fixed thereto so as to cut a light passage portion. Thus, according to the present invention, (1) it is possible to form a polarization control element that always converts a linearly polarized wave even if an arbitrary polarized wave is input, on a substrate on which an optical waveguide or an optical fiber is fixed. (2) High-speed phase modulation is possible and a high-speed waveguide optical switch can be realized. (3) A variable wavelength filter that can select only light of an arbitrary wavelength can be mounted on a substrate on which an optical waveguide or an optical fiber is fixed. (4) An optical attenuator can be realized on an optical fiber or an optical waveguide. (5) The intensity of passing light can be monitored. (6) In addition, all kinds of devices using the spatial beam can be mounted on the substrate on which the optical waveguide or the optical fiber is fixed, and the waveguide type optical element can be miniaturized.

[Brief description of drawings]

FIG. 1 is a diagram for explaining a schematic configuration of an optical waveguide substrate or an optical device substrate according to an embodiment of the present invention and its manufacture.

FIG. 2 is a diagram showing a step of forming a groove in the optical fiber substrate of the present embodiment.

FIG. 3 is a diagram for explaining the schematic configuration of the surface-type optical element of the present embodiment and its fabrication.

FIG. 4 is a diagram for explaining a mounting process of the surface-type optical element of the present embodiment.

FIG. 5 is a diagram for explaining a basic mounting process of the method of mounting the surface-type optical element of the present embodiment.

FIG. 6 is a diagram showing a mounting completed state of the surface-type optical element of the present embodiment.

FIG. 7 is a diagram showing a state in which two planar optical elements or liquid crystal elements are inserted into one groove of the present embodiment.

FIG. 8 is a diagram for explaining the principle of the liquid crystal rotation wavelength plate according to Example 1 of the embodiment.

FIG. 9 is a diagram for explaining a manufacturing process of the thin liquid crystal rotation wavelength plate of the first embodiment.

FIG. 10 is likewise a diagram for explaining a manufacturing process of the thin liquid crystal rotation wavelength plate of Example 1.

FIG. 11 is a diagram showing a manufacturing process of an infinite tracking polarization control device using the liquid crystal rotation wavelength plate of the first embodiment.

FIG. 12 is a diagram showing a production process of a parallel alignment liquid crystal plate of Example 2 of the present embodiment.

FIG. 13 is likewise a diagram showing a process of manufacturing a parallel alignment liquid crystal plate of Example 2.

FIG. 14 is a diagram showing a process of manufacturing the polarization control element using the groove wall surface according to the second embodiment.

FIG. 15 is a diagram showing a step that follows FIG. 14 (C).

FIG. 16 is a diagram showing a structure of an optical shutter array.

FIG. 17 is a diagram for explaining a manufacturing process of the PLZT modulator according to Example 3 of the present embodiment.

FIG. 18 is a diagram showing a step that follows FIG.

FIG. 19 is a drawing for explaining the manufacturing process of the PLZT modulator of the modification of the third embodiment.

FIG. 20 is a diagram for explaining a step of inserting a polyimide wave plate by RIE in Example 4 of the present embodiment.

FIG. 21 is a diagram for explaining an element insertion method when a TEC fiber is used in Example 7 of the present embodiment.

FIG. 22 is a diagram showing a step that follows FIG.

FIG. 23 is a diagram showing an optical device using a typical conventional collimating fiber.

[Explanation of symbols]

11-1-1 ... Optical Waveguide Substrate 11-1-1A ... Optical Fiber Substrate 11-1-2 ... Glass Plate 11- 1-3 ... Optical Fiber Core 11-1-1 ... Optical Fiber Coating 11- 1- 5 ... V-groove array 11-1-6 ... Adhesive 11-2 ... Vertically provided groove 11-3 ... Dicing blade 11-4 ... Surface type optical element 11-5 ... Support member (block) 11-6 ... Adhesion Agent 11-7 ... Alignment mark 11-8 ... Window (light transmitting portion) 11-9 ... Electrode 11-10 of optical device ... Pattern electrode 11-11 ... Optical adhesive 11-12 ... Extraction electrode 12-1 ... Light Through which the window passes 12-2 ... 8 electrodes with central symmetry 12-3 ... Glass substrate 12-4 ... Vertically aligned liquid crystal 12-5 ... Light beam passing through window 12-6 ... Liquid crystal molecules rotating 13 -1 ... Centrally symmetrical 8-electrode pattern 13-2 ... Glass substrate 13-3 ... Glass substrate 13-4 cut into corners ... Glass Block 13-5 ... Spacer 13-6 ... Nematic liquid crystal 13-7 ... Glass polarizer 13-8 ... Transmissive detector 14-1 ... Stripe transparent electrode (ITO) 14-2 ... Glass substrate 14-3 ... Polished glass substrate 14-4 ... Glass block 14-5-1 ... Spacer 14-5-2 ... Alignment film 14-5-3 ... Liquid crystal 14-6 ... Core 14-7 ... Parallel alignment nematic element 14-8 ... Parallel alignment nematic element 14 -9 ... Glass polarizer 14-10 ... Transmissive photodetector 15-1 ... Transparent electrode 15-2 ... Alignment film 15-3 ... Rubbing roll 15-4 ... Glass block 15-5 ... Glass block 15-6 ... 0 degree Alignment homogeneous liquid crystal 15-7 ... Twisted nematic liquid crystal 15-8 ... Glass polarizer 15-9 ... Transmissive detector 16-1 ... PLZT ceramics substrate 16-2 ... Shutter portion 16-3 ... Electrodes 1 sandwiching convex portion PLZT -4 ... Electrode separation part 17-1 ... Convex electrode 17-2 ... Convex PLZT 17-3 ... Slicing dicing surface 17-4 ... Convex PLZT chip 17-5 ... Glass block with electrode 17-6 ... Conductive paste Reference numeral 17-7 ... Electrode attached to glass block 17-8 ... Waveguide 17-9 ... Adhesive 17-10 ... PLZT square bar 17-11 ... PLZT window portion 17-13 ... Electrode 17-14 Adhesive 17-15 ... Thin glass plate 17-16 Electrode pattern 17-17 ... Glass block 18-1 ... Optical waveguide 18-2 ... Groove 18-3 ... Polyimide film 18-4 ... Glass block 18-5 ... Adhesive 18-6 ... Refractive index matching adhesive 19-1 ... Fiber with input collimator 19-2 ... Fiber with output collimator 19-3 ... Rotation λ / 2 plate 19-4 ... Rotation λ / 4 plate 19-5 ... Rotation or movement Type ND filter 1 9-6 ... Liquid crystal variable wavelength filter (piezo control Fabry-Perot interferometer variable wavelength filter) 19-7 ... Polarizer 1 19-8 ... Polarizer 2 19-9 ... Faraday rotator 101 ... Optical fiber core 102 ... Coating 103 … Expanded core

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G02F 1/13 505 G02B 6/12 J H01L 31/0232 H01L 31/02 C F term (reference) 2H038 AA21 AA32 AA33 BA27 CA52 2H047 KA03 KB09 MA07 NA02 NA03 NA04 QA02 QA03 QA04 QA05 RA08 TA05 TA43 2H079 AA02 AA12 BA02 DA04 EA12 EA28 EB06 EB17 GA04 KA17 2H088 EA37 EA47 EA49 HA30 5F088 FA01 AB05 EA05 EA14

Claims (17)

[Claims] 1. A substrate on which an optical waveguide or an optical fiber is fixed is formed with a groove so as to cut a light passage portion, and the groove is inserted substantially perpendicularly to the groove and fixed, and actuated by applying a voltage. A waveguide type optical element having a thin active surface-type optical element and a support member attached to the surface-type optical element. 2. The waveguide type optical element according to claim 1, wherein the width W of the groove is w <W <300 μm, where w is the thickness of the planar optical element. 3. The waveguide type optical element according to claim 1, wherein the support member has an electrode for taking out an electrode of the planar optical element. 4. The support member is made of glass, ceramics,
It is any one of a rectangular, L-shaped, and pillar-shaped block made of plastic, and has a height h and a width I of the block, and a length s of the planar optical element at a portion protruding from the block. The relationship is that when the surface type optical element in which the supporting member is attached to the surface of the substrate on which the optical waveguide or the optical fiber is fixed is mounted,
2. The waveguide type optical element according to claim 1, wherein I / h> s / I is set in order to make the surface type optical element slightly inclined so as not to fall. 5. The planar optical element has an electrode, and when the block is a rectangular block, an L-shaped electrode is wired in one corner on the upper surface of the block, and the electrode of the planar optical element. 4. The waveguide type optical element according to claim 3, wherein the electrode of the planar type optical element is connected to the electrode of the block and the electrode of the planar type optical element are taken out from the upper surface side of the block. 6. The planar optical element comprises a PbS photodetector formed on glass, an a-Si photodetector, a photodetector having a thin semiconductor device, a semiconductor optical modulator, and metal fine particles in glass. Variable wavelength consisting of polarizers aligned in the long axis direction, optical crystal wave plate, dielectric multilayer filter deposited on glass substrate, ND filter, electro-optic crystal sandwiched by dielectric multilayer mirrors or electro-optic ceramics The waveguide type optical element according to claim 1, which is one of a filter and an electro-optic crystal / electro-optic ceramic polarization modulator. 7. The planar optical element is a liquid crystal element, the support member is a pair of blocks attached so as to sandwich the liquid crystal element, and the liquid crystal element is attached to one surface of each block facing each other. The conductor according to claim 1, further comprising: a thin glass plate on which electrodes are patterned, an alignment film formed on the thin glass plate, which has been subjected to an alignment treatment such as rubbing, and a liquid crystal filled between the alignment films. Waveguide optical device. 8. Eight electrodes are radially formed on each glass plate of the liquid crystal element so as to be center-symmetrical, and a central portion of the radial electrodes has a diameter of 20 μmφ to 50 μmφ through which light passes. By having a window and adjusting the voltage applied to the eight electrodes,
8. The waveguide type optical element according to claim 7, wherein an electric field having an arbitrary intensity of 360 degrees and an arbitrary intensity can be applied to the central portion, and when an arbitrary polarized wave is incident, it can be converted into an arbitrary polarized wave with infinite tracking. 9. The planar optical element is a thin optical modulator, and the optical modulator has a PLZT having four grooves cut from four side surfaces.
A thin plate, four electrodes formed from the four side surfaces of the PLZT thin plate to the inside of each groove cut in, a conductive adhesive filling the cut grooves, and affixed to the PLZT thin plate, And a thin plate glass with four electrodes to which the four electrodes are respectively connected, the thin plate glass with four electrodes being fixed to the support member so that light passes through the centers of the four electrodes, The electrodes of the container are taken out to the outside, and by adjusting the voltages applied to the four electrodes, an electric field of 360 degrees in any direction and strength is applied, and the polarization of incident light is linearly traced infinitely. The waveguide type optical element according to claim 1, which has a function of converting to a polarized wave. 10. The waveguide type optical element according to claim 9, wherein the optical waveguide or the optical fiber fixed to the substrate is a core expanding fiber. 11. A thin active surface-type optical element which is formed by cutting a light-passing portion on a substrate having an optical waveguide or an optical fiber fixed thereto and which is actuated by applying a voltage. A method for producing a waveguide type optical element, comprising: adhering a supporting member so that a portion protrudes; and inserting and fixing the protruding portion of the planar optical element to which the supporting member is adhered, in a substantially vertical manner in the groove. 12. The width W of the groove is w <W <300 μm, where w is the thickness of the planar optical element.
1. The method for producing a waveguide type optical element according to 1. 13. The surface-type optical element is inserted into the groove before the groove is inserted so that a light passage portion of the surface-type optical element inserted in the groove corresponds to a position of a core of the optical fiber or the optical waveguide. An alignment mark is provided at a position where the distance from the portion through which the light passes to the core position is measured, and when the planar optical element is attached to the support member, the alignment mark and the support are supported. The method for producing a waveguide type optical element according to claim 11, wherein the bottom surface of the member and the bottom surface of the member are bonded together. 14. The support member is a square, L-shaped, or pillar-shaped block made of any one of glass, ceramics, and plastic, and the height h and width I of the block and the block The relation of the length s of the planar optical element in the protruding portion is expressed by I / h>
s / I, and in the step of inserting the protruding portion of the planar optical element into the groove, the planar optical element to which the supporting member is attached is tilted slightly on the surface of the substrate so as not to fall. The method for producing a waveguide type optical element according to claim 11, further comprising a step of sliding the surface type optical element toward the groove and moving the surface type optical element into the groove to fix the surface type optical element. 15. In the process of sliding the planar optical element,
15. The method of manufacturing a waveguide type optical element according to claim 14, wherein both the support member and the end of the planar optical element are in contact with the surface of the substrate. 16. The surface type optical element is inserted into the groove when the surface type optical element is dropped into the groove, and an end portion of the surface type optical element bends by being caught in the groove. Of manufacturing a waveguide type optical element of. 17. The planar optical element has an electrode, and when the block is a rectangular block, an L-shaped electrode is wired in one corner on the upper surface of the block, and the electrode of the planar optical element, 12. The method for producing a waveguide type optical element according to claim 11, further comprising a step of connecting the electrodes of the bonded blocks and taking out the electrodes of the planar optical element from the upper surface side of the block to the outside.