JP2002062439A - Two-dimensional magnification and reduction optical device and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thin two-dimensional magnification and reduction optical device at a low cost and a method for manufacturing the device without using a conventional projection method. SOLUTION: The device consists of an assembled body of polymer optical fibers 53 in such a manner that the end faces of a plurality of polymer optical fibers 53 are positioned on a single plane in the reduction face 55 by a holding material 54 for the reduction face and that the end faces of a plurality of polymer optical fibers 53 are positioned on a single plane in the magnification face 52 by a holding material 51 for the magnification face. The relation of the relative position of the end face of the polymer optical fiber 53 with the adjacent polymer optical fiber 53 is kept in the other end face. The relative distance between the center position in the cross section of the optical fiber 53 and the center position in the cross section of the adjacent optical fiber on the magnification face 52 is larger than the relative distance between the center position in the cross section of the optical fiber 53 and the center position in the cross section of the adjacent optical fiber 53 in the reduction face 55.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical device used as an enlargement or reduction optical system in an apparatus for displaying or capturing images, and a method for manufacturing the optical device. The relative distance between the cross-sectional center position on the enlarged surface of the index region and the cross-sectional center position on the adjacent high-refractive-index region on the enlarged surface is the cross-sectional center position on the reduced surface and the other high-refractive index adjacent to it. The present invention relates to a two-dimensional enlargement / reduction optical device capable of realizing a high-magnification optical device without using a lens or the like by being larger than a relative distance of a cross-sectional center position on a reduction surface of a region, and a method of manufacturing the same.

[0002]

2. Description of the Related Art There are two types of display devices for displaying information: a 1: 1 display device such as a liquid crystal monitor for a personal computer, which is generally called a flat panel display, and an enlarged projection display device such as a rear projection type liquid crystal television. There is. The unit-size display device has the advantage that the thickness of the display can be reduced and the space required for installation is small, but when a large screen, for example, a screen of 30 inches or more is obtained, the manufacturing process becomes complicated. However, there is a disadvantage that the cost is increased due to poor yield and the like. On the other hand, the enlarged projection display device has an advantage that it can provide a large display size of 50 inches or more at a lower cost than a 1 × display device.
It is difficult in principle to make the thickness of the display as thin as that of the unit-size type, and there is a disadvantage that the space required for installation is widened.

[0003] In a magnified projection display device such as an existing liquid crystal television, a technique of a magnifying optical system using a lens or a mirror is used. Otherwise, as shown in FIG. 1, a method of enlarging an image by aligning and arranging optical fibers with respect to a small image and disposing the optical fibers discretely (see Japanese Patent Application Laid-Open No. 05-88617). (Hereinafter, method A), as shown in FIG. 2, a method of enlarging an image by using a plurality of blocks obtained by diagonally cutting a fiber assembly (see Japanese Patent Application Laid-Open No. 06-51142)
Method B), as shown in FIG. 3, a method of transmitting an image to a display panel using an optical fiber 3 in order to eliminate a seam between panels of a display device including a plurality of liquid crystal display panels (Japanese Patent Laid-Open No. 09-252444). (Hereinafter referred to as “publication”) (hereinafter referred to as method C), and a method of enlarging the display size of a pixel using a tapered light guide path as shown in FIG.
No. 02) (hereinafter, method D) and the like have been proposed.

[0004]

A conventional method A (Japanese Patent Laid-Open No.
In the configuration of Japanese Patent Application Laid-Open No. 05-088617), as a means for expanding the display area, one end of the optical fiber is fixed in a prism shape using a method of discretely arranging the pixels that have been assembled, and the other end is fixed to the panel. A technique of inserting into a large number of pores opened at intervals has been used. In this method, even if the number of pixels is very large, it is necessary to insert fibers one by one into a predetermined position, and it is not possible to provide a device which is very troublesome and inexpensive. A similar method is described in, for example, JP-A-07-8.
Although disclosed in Japanese Patent No. 4127, there is also a problem that it is difficult to provide an inexpensive optical device because the optical fiber is inserted into the pore.

[0005] Next, in the configuration of method B (Japanese Patent Laid-Open No. 06-51142), a plurality of fiber aggregates are used in combination, but when one fiber aggregate is combined with another fiber aggregate, The difficulty in efficiently transmitting light from the first fiber aggregate to the next fiber aggregate;
In addition, there is a problem in optical coupling and manufacturing such that alignment for bonding two fiber aggregates is very difficult when the fiber diameter is small. next,
The configuration of the method C (Japanese Patent Application Laid-Open No. 09-252444) has an advantage that a thin, seamless large-screen display device can be realized by combining a display device with a small screen, but basically, the method A ( As in the case of Japanese Patent Application Laid-Open No. 05-088617), it is difficult to provide an inexpensive optical device because the optical fibers are arranged one by one with extra effort.

Next, in the structure of method D (Japanese Patent Laid-Open No. 07-43702), the display size of each pixel is enlarged, but the pixel position and the display position in the normal direction coincide with each other. There is a problem that the size of the entire image is not increased and the image is not enlarged. In addition to the above conventional techniques, a technique for enlarging an image using a metal through-hole (for example, see Japanese Patent Application Laid-Open No. 5-80319), a technique for enlarging an image using a metal reflector (for example, Kaihei 7
-294747). However, a method using light transmission by reflection on a metal surface is different from a light transmission method using an optical fiber or a light guide, because light loss due to reflection on a metal surface is large and is not suitable for practical use.

With an increase in demand for image reading apparatuses such as facsimile machines, image scanners and digital copying machines,
There is a demand for miniaturization of an image sensor that converts image information into an electric signal, and a miniaturized image reduction device is required. For example, as a method of transmitting a one-dimensional image read from a wide original to a small one-dimensional CCD device,
A method has been proposed in which a tapered optical waveguide is arranged on a document surface and is coupled with a thin optical waveguide on a coupling surface with a CCD (for example, see Japanese Patent Application Laid-Open No. 9-37038). This method is suitable as a method for enlarging / reducing a one-dimensional image, but as a method for forming a light guide path, an optical epoxy resin is applied to a substrate having a groove formed by injection molding, and the groove is filled. The light guide path is created by curing the epoxy resin buried in the groove. This method is suitable for creating a two-dimensional optical waveguide that transmits a one-dimensional image, but when creating a three-dimensional light guide, the mold shape during injection molding becomes very complicated. It is not suitable as a manufacturing method for creating a light guide path for transmitting a two-dimensional image.

Next, as a product for enlarging or reducing an image without using a lens, "Ta
perMag ”is on sale. In this product, a large number of optical fibers are bundled at high density, melted and processed into a tapered shape. This product has the same basic optical principle as that of the present invention for enlarging or reducing an image, but it is difficult to obtain a large display area of 100 mm square or more because glass fibers are bundled and processed. Also, it is difficult to increase the taper angle when processing in a tapered shape due to processing problems. For example, when trying to obtain a display screen of about 30 inches, the thickness of the device cannot be reduced to 30 cm or less. Also, Japanese Patent Application Laid-Open No. 06-59140 proposes a tapered glass optical fiber having a structure similar to that of the above “TaperMag” as an image enlarging means, but does not disclose any specific manufacturing method. .

Various methods have been reported so far for producing optical waveguides. However, these reports are methods for fabricating single fibers or one-dimensional fiber arrays, and two-dimensional arrays as required by the present invention, and three-dimensional fibers with complicated shapes. There are no reports on how to make arrays. For example, Japanese Patent Application Laid-Open
JP-A-326660 discloses a manufacturing method in which specific light is incident on a photocurable resin from a light inlet and a light guide path is formed along an optical axis. This manufacturing method simply produces a single light guide, and is clearly different from a technique for manufacturing a two-dimensional optical device using a plurality of fiber arrays. In Japanese Patent Application Laid-Open No. 05-157923, ions are introduced into glass by an electric field to produce a three-dimensional optical waveguide, but a complex structure such as a device required by the present invention is produced. Is not realistic.

Accordingly, an object of the present invention is to provide a two-dimensional enlargement / reduction optical device which solves these conventional problems and realizes a thin type without enlarging or reducing the entire image and the pixel size itself without using a conventional projection system. To provide. Another object of the present invention is to provide a very inexpensive manufacturing method as a manufacturing technique of an enlarged optical device that discretely bundles optical fibers.

[0011]

In order to achieve the above object, in a two-dimensional enlargement / reduction optical device according to the present invention, in a device in which a plurality of regions having a high refractive index are formed, each of the high refractive regions is one. And the device is an assembly of light guide paths made of a polymer optical fiber. Further, one end face of the plurality of polymer optical fibers is located substantially on one plane, and the other end faces of the plurality of polymer optical fibers are also located substantially on one plane. Further, in order to obtain a characteristic of transmitting an image in an enlarged or reduced manner, the relative positional relationship between one end face of the plurality of high refractive index regions is maintained also on the other end face.

Further, for the purpose of enlarging or reducing an image, one end face of a high refractive index area (hereinafter referred to as an enlarged face)
The relative distance between the cross-sectional center position of the high-refractive-index area and the cross-sectional center position of another high-refractive-index area adjacent thereto on the enlarged surface is the cross-section at the other end face of the high-refractive-index area (hereinafter referred to as a reduced surface) It is also characterized in that it is larger than the relative distance between the center position and the cross-sectional center position on the reduced surface of another high refractive index region adjacent thereto. Furthermore, in order to obtain the characteristic of enlarging or reducing an image without distortion, the ratio of the cross-sectional area of the high-refractive-index region on the enlarged surface to the cross-sectional area on the reduced surface is substantially the same in a plurality of high-refractive-index regions. There is also a feature.

Further, it is also characterized in that a part of the member for keeping the relative position of the polymer optical fiber constant is a foamed material. It is also characterized in that the foam material is used only in a region near the enlarged surface of the high refractive index region. Also,
At least in the stage before the foaming material described above foams, the polymer optical fiber has no adhesiveness to the optical fiber or is coated with a surface coating film having low adhesiveness. It is also characterized. The above-mentioned surface coating material is characterized in that the relative positional relationship with the adjacent surface coating material is kept constant from one end to the other end.

(10) The surface coating material is characterized in that it is a material that can be bonded to an adjacent surface coating material. (11) The cross section of the light guide path made of the polymer optical fiber has a substantially constant cross-sectional area from the reduced surface described above to the vicinity of the enlarged surface, and approaches the enlarged surface in the vicinity of the enlarged surface. It is also characterized in that the cross-sectional area becomes larger as the distance increases. (12) The ratio of the cross-sectional area of the light guide on the enlarged surface to the cross-sectional area of the light guide on the reduced surface is substantially the same in a plurality of high refractive index regions. (13) In the vicinity of the enlarged surface whose cross-sectional area increases with approaching the enlarged surface,
The light guide path is characterized in that it is formed at a stage after the above-described foamed material foams.

(14) In the vicinity of the enlarged surface where the cross-sectional area increases as approaching the enlarged surface, one end of the polymer optical fiber is immersed in a photocurable resin mixture and light enters from the other end. It is also characterized by using a photocurable resin material prepared by the method as a raw material. (15) The polymer optical fiber coated with the surface coating material is formed as an aggregate composed of a plurality of block units after forming an aggregate composed of a plurality of polymer optical fibers in advance as one block. Also features. (16) The cross-sectional shape of the block is also substantially square. (17) The cross-sectional shape of the block is also substantially hexagonal. (18) In the above, as a means for reducing the relative distance between the cross-sectional center position on the reduced surface and the cross-sectional center position on the reduced surface of another polymer optical fiber adjacent thereto, it is also characterized by using a shrinkable material. I have. (19) The shrinkable material is a heat-shrinkable sheet.

[0016]

Embodiments of the present invention will be described below in detail with reference to the drawings. (First Embodiment) FIG. 5 is a structural view of a two-dimensional enlargement / reduction optical device showing a first embodiment of the present invention. The two-dimensional enlargement / reduction optical device of the present embodiment is composed of an aggregate of polymer optical fibers 53 as shown in FIG.
On the reduced surface 55 of FIG.
The end face 3 is located on substantially one plane by the reduced surface holding member 54. In the enlarged surface 52, the end surfaces of the plurality of polymer optical fibers 53 are located on substantially one plane by the enlarged surface holding material 51. Further, the relative positional relationship between the end face of the polymer optical fiber and the adjacent polymer fiber 53 is maintained at the other end face. Further, the relative distance between the cross-sectional center position of the optical fiber 53 on the enlargement plane 52 and the cross-sectional center position of another optical fiber 53 adjacent thereto is adjacent to the cross-sectional center position of the optical fiber 53 on the reduction plane 55. The optical fibers 53 are arranged so as to be larger than the relative distance between the center positions of the cross sections of the other optical fibers 53.

The principle of the present invention is as follows. The display image is set close to the reduced surface 55 shown in FIG. Specifically, a small liquid crystal display, a small electroluminescence display, a small CRT, and the like are used. Outgoing light from these display images enters the polymer optical fiber 53. Of the incident light, light satisfying the condition of total reflection at the interface between the high refractive index region and the low refractive index region propagates through the optical fiber 53 toward the enlarged surface 52.
The relative distance between the cross-sectional center position of the optical fiber 53 on the enlargement plane 52 and the cross-sectional center position of another optical fiber 53 adjacent thereto is different from the cross-sectional center position of the optical fiber 53 on the reduction plane 55 and other adjacent centers. Since the distance is larger than the relative distance between the cross-sectional center positions of the optical fibers 53, the pixels incident from the reduced surface 55 are enlarged and displayed on the enlarged surface 52.
Conversely, when an image is placed on the enlarged surface 52 and observed from the reduced surface 55 side, the image is reduced and displayed. FIG.
FIG. 2 is a three-dimensional view showing an example of the device of the present invention. The ends of the plurality of polymer optical fibers 53 form a matrix at equal intervals on the enlarged surface 52. Polymer optical fiber 5
3 are gathered while keeping the same positional relationship on the reduced surface 55 while narrowing the interval between the adjacent optical fibers 53.

According to the present invention, the optical path length from the enlargement plane 52 to the reduction plane 55 when enlarging and reducing an image can be shortened, so that the thickness of the entire device is smaller than that of the prior art and the entire device is thinner. It has the feature of being able to reduce the weight. As mentioned earlier, the product sold under the name `` TaperMag '' is made by bundling, melting and stretching glass fibers, so the taper angle when processing into a tapered shape due to processing problems. Difficult to make big. Therefore, it is difficult to make the distance (the thickness of the device) from the reduction plane to the enlargement plane smaller than the diagonal length of the enlargement plane. As described above, a feature of the present invention is that a thin and light optical device can be provided by arranging a large number of inexpensive polymer optical fibers.
Further, as a method for maintaining the relative positional relationship between adjacent polymer optical fibers, the polymer optical fiber is covered with a surface coating material having very low or no adhesiveness. Further, the relative distance between the cross-sectional center position of the optical fiber on the enlargement plane and the cross-sectional center position of another optical fiber adjacent thereto is calculated by calculating the cross-sectional center position of the optical fiber on the reduction plane and the cross-sectional center of another optical fiber adjacent thereto. As a means for increasing the relative distance between the center positions, a foam material is also used.

(Second Embodiment) FIG. 7 is a structural view of a two-dimensional enlargement / reduction optical device showing a second embodiment of the present invention. In the configuration of the first embodiment shown in FIG. 5, there is no problem when the device to be brought close to the reduction surface 55 is a light emitting device, but when the device is a reflection type, the enlargement occurs. Since the aperture ratio of the optical fiber 53 on the surface 52 is low, there is a problem that an image becomes dark. This problem is solved by the second embodiment. That is, as shown in FIG. 7, the problem can be solved by providing the optical fiber 53 with a taper so that the cross-sectional area of the light guide path increases in the vicinity of the enlarged surface 52 in the vicinity of the enlarged surface 52. As a method of forming a tapered shape in the optical fiber 53, a method of immersing a polymer optical fiber in a photo-curing resin mixed solution, which was performed by Yamashita of Toyoda Central Research Laboratory Co., Ltd., and injecting light from one fiber end face is known. (See IEICE, IEICE Technical Report OEM99-94, 1999-10).

(Embodiment of Manufacturing Method) The manufacturing method of the present invention will be described step by step. FIG. 8 is a partially enlarged view of a section of a polymer optical fiber used in the present invention, and FIG. 9 is a view showing a block in which the polymer optical fibers according to the present invention are bundled. First, as shown in FIG. 8, a polymer optical fiber 61 covered with a surface coating material 63 having very weak adhesion to the fiber 53 is prepared. Examples of the polymer optical fiber 53 include those using PMMA as a core material and fluoropolymer as a cladding material. In addition, examples of the surface covering material 63 include a polyethylene resin. Next, FIG.
As shown in (1), a block 64 is formed by bundling a plurality of polymer optical fibers 61 covered with a surface coating material 63 two-dimensionally. The coating materials 63 are bonded by an adhesive, heat, light, pressure, or the like. The cross-sectional shape of this bundled block 64 is
Approximately square or hexagonal. The reason why the shape is quadrangular or hexagonal is that when a plurality of blocks 64 are further bundled, no gap is left between the blocks.

FIG. 10 is a diagram showing a state in which a plurality of blocks of FIG. 9 are bundled and one ends thereof are aligned. Next, as shown in FIG. 10, the plurality of blocks 65 are further bundled so as to have a desired number of pixels (the number of fibers) with one end face aligned. Also at this time, the covering materials 63 are bonded with adhesive, heat,
Bonded by light, pressure, etc. When the bundles are bundled as shown in FIG. 10, the lengths of the fibers of the blocks 64 bundled in FIG. 9 are cut to a predetermined length according to the final pixel position. That is, the block 64 located near the center of the final device is cut short, and the block 64 located near the periphery is cut long. The reason for this is that, as can be seen from FIG. 5, the optical fiber 53 located near the center of the device does not change much in the vertical positional relationship between the reduced surface 55 and the enlarged surface 52. This is because the vertical position of the fiber 53 on the reduction plane 55 and the enlargement plane 52 greatly changes, so that the optical fiber 53 naturally needs a long length.

FIGS. 11 to 14 are partial enlarged views of FIG. 11 is a diagram of a process of removing the surface coating material from the end face of the fiber, FIG. 12 is a diagram of a process of applying a foaming agent, FIG. 13 is a diagram of a process of foaming the foaming agent, and FIG. It is a figure of the cutting process of the other end side. First, the fiber surface coating material 66 in the portion where the end faces of the bundled fibers in FIG. 10 are aligned is removed. Next, as shown in FIG. 12, a foaming agent 67 is applied to a part of the optical fiber from which the surface coating material 66 has been removed. Next, as shown in FIG. 13, the foaming agent 67 is foamed. An important point in this step is that the adhesiveness between the optical fiber and the surface coating material 66 of the fiber is very weak or completely non-adhesive with the surface coating material 66. As the foaming agent 67 expands, the distance between one end faces of the adjacent fibers becomes longer. On the other hand, since the fiber coating materials 66 are adhered to each other, the force of expanding the expanding agent causes the fiber 68 to slide out of the sheath of the surface coating material 66. Examples of the foamed material include hard polyurethane. Finally, as shown in FIG.
The opposite end face of the fiber 68 on which the foaming agent 67 is applied is cut so that the fiber end face is aligned, and the optical fiber end face of this face is fixed using an adhesive or the like as necessary.

FIG. 15 is a view showing a step of adding a taper to the optical fiber, and FIG. 16 is a view showing a step of bonding a shrinkable material to the tip of the optical fiber. When this device is used for enlargement / reduction of a reflective display device, it can be solved by adding a taper to the optical fiber as described above. After the step of FIG. 14, as shown in FIG. 15, the enlarged surface of the polymer optical fiber is
2 and irradiate ultraviolet rays 70 from the other fiber end face, so that a tapered light guide path 7
Form one. Thereby, the tapered light guide path 71 which is an enlarged surface of the reflective display device can be realized. Examples of the photocurable resin to be used include acrylic and methacrylic resins. Further, since the optical fiber on the reduction surface side is covered with the surface coating material 69, the filling rate of the optical fiber on the reduction surface side can be increased with the outer diameter of the surface coating material 69 while the surface coating material 69 is left. The more it goes down. As a result, there is a possibility that the transmission efficiency of the light of the image incident from the reduction surface may be deteriorated. As a method for solving this problem, as shown in FIG. 16, the surface coating material 69 on the reduced surface side is removed, and a contraction material 73 is adhered to the tip of the optical fiber.
Thereafter, the shrink material 73 is shrunk using heat, a solution, or the like. Thereby, the filling rate of the optical fiber on the reduction surface side can be increased.

Here, in order to bundle the optical fibers, FIG.
And the merits of passing through two steps as shown in FIG. If the process of FIG. 10 is performed without going through the process of FIG. 9, two problems occur. First, when a very large number of optical fibers 61 are bundled at a time, it is difficult to maintain a relative positional relationship between one end face and the other end face of the fibers 61. When the number of fibers reaches thousands or tens of thousands, it is necessary to prepare thousands to tens of thousands of fiber reels in order to maintain the relative positional relationship between the fibers 61, and the equipment becomes very large for bundling. Would. on the other hand,
A block 64 with a small number of fibers as shown in FIG.
In order to form (1), dozens to hundreds of fiber reels need to be prepared, and the device for bundling can be small. The second problem is that if a very large number of optical fibers 61 are bundled at one time, the length of the optical fibers 61 cannot be adjusted according to the finally required length, and The whole will be bundled according to the peripheral part that needs to be used. In this case, the length of the central portion is longer than necessary, and the raw materials cannot be used effectively. On the other hand, if the fibers are bundled in the block 64 having a small number of fibers as shown in FIG. 9, the length of the fiber of the block 64 is cut according to the finally required length as described above. Because they can be bundled, the effective use of raw materials becomes possible.

(Experimental Example 1) Step 1: (See FIG. 8) A polymer optical fiber light was prepared using black polyethylene as a surface coating material, a methacrylic resin as a core material, and a transparent fluororesin as a cladding material. The core diameter of this optical fiber is 100
μm, the outer diameter of the cladding is 130 μm, and the outer diameter of the black polyethylene surface coating material is 200 μm. The surface coating and the optical fiber are not bonded. A large number of the optical fibers 61 were previously bundled as shown in FIG. In the first experimental example, a total of 25 pieces in 5 rows and 5 columns were bundled so as to form a square, and one block 64 was formed. Before bundling, the surface coating materials 63 were bonded by applying a methylal-diluted epoxy adhesive. The length of one side of the block 64 was about 1 mm.

Step 2: (Refer to FIG. 9) The block 64 created in Step 1 is divided into five blocks such that the end face of one block is located on a plane as shown in FIG.
A total of 25 blocks 64 in 5 rows and 5 columns were bundled into a square. The length of one side of the bundled square was about 5 mm. The adhesion between the blocks 64 was performed by applying a methylal diluted epoxy adhesive. As a result, 25 vertical and 25 horizontal
A total of 625 polymer optical fiber bundles 65 were prepared. The optical fiber length of each block 64 when bundled into the block 65 is 15 mm for the block located at the center, 20 mm for eight blocks adjacent to the center, and 1
The block of No. 6 was 25 mm. Step 3: (see FIG. 12) The surface of the optical fiber prepared in the previous step, which is aligned with one plane, is immersed in a 1,1,2-trichloroethane solution at a liquid temperature of 70 ° C. for 10 seconds, and a black polyethylene surface is formed. The coating was removed 2 mm from the tip.

Step 4: Next, a hard polyurethane material obtained by rapidly diffusing an organic isocyanate and a range solution for 4 seconds is applied to an aluminum plate in a thickness of 0.5 mm, and the tip of the optical fiber from which the surface coating material 63 has been removed in step 3 is quickly obtained. Was adhered. Step 5: (See FIG. 13)
The rigid polyurethane raw material was foamed by heating to 5 ° C. and holding for 10 minutes. By this step, the distance between the center positions of the optical fiber cross-sections of adjacent optical fibers was increased from 0.2 mm before the rigid polyurethane foamed to 1 mm. Thereafter, the foamed hard polyurethane was separated from the aluminum plate. As a result, the bundle of optical fibers on the surface held by the hard polyurethane became a square having a side of about 25 mm.

Step 6: (See FIG. 14) With the optical fiber tip surface held by hard polyurethane being aligned with a flat surface, the black polyethylene surface covering material 67 on the side of the surface where the distance between the optical fibers is widened and the polymer The optical fiber 68 was bonded. As the adhesive, an epoxy adhesive diluted with methylal was used in the same manner as when the surface coating materials were bonded in step 2. After the adhesive was cured, the surface covering material 67 and the entire optical fiber bundled at a position 2 mm from the tip of the surface covering material 67 on the side where the distance between the optical fibers was widened were cut. The cut surface was also bonded to the black polyethylene surface covering material 67 and the polymer optical fiber using a methylal diluted epoxy adhesive. Step 7: Finally, both end faces of the optical fiber bundle were optically polished using alumina. The finished product obtained in Experimental Example 1 is referred to as Sample 1.

(Experimental Example 2) (See FIG. 15) The sample 1 prepared in Steps 1 to 7 of Experimental Example 1 was used for an ultra-high pressure mercury lamp from the side where the distance between the center positions of the optical fiber sections of adjacent optical fibers was short. When light was introduced and immersed in a phenoxyethyl acrylate photocurable resin mixture liquid 72, the curing reaction proceeded by a photopolymerization reaction, and a tapered fiber was self-formed at the initial 2 mm of the reaction, and finally the fiber diameter became 200 μm. It became. After forming the tapered fiber, the resin in the uncured portion was removed with acetone, and the clad layer was formed by thermosetting a fluorinated epoxy having a refractive index higher than that of the photocurable resin. Finally, the optical fiber surface formed into a tapered shape was optically polished using alumina. The finished product obtained in Experimental Example 2 is referred to as Sample 2.

(Experimental Example 3) (see FIG. 13) The distance between the optical fibers was adjusted with the sample prepared up to Step 5 of Experimental Example 1 in a state where the optical fiber tip surface held by hard polyurethane was aligned with a plane. The black polyethylene surface coating material on the side of the spread surface and the polymer optical fiber were bonded. As the adhesive, an epoxy adhesive diluted with methylal was used in the same manner as when the surface coating materials were bonded in step 2. After the adhesive was cured, the surface covering material 69 and the entire optical fiber bundled at a position 2 mm from the tip of the surface covering material 69 on the side where the distance between the optical fibers was widened were cut. This cut surface is placed in a 1,1,2-trichloroethane solution at a temperature of 70 ° C. for 1 hour.
By soaking for 0 second, the black polyethylene surface coating material 69 was removed by 1 mm from the tip. An epoxy-based adhesive was applied to the side surface of the optical fiber from which the surface coating material 69 was removed, and a heat-shrinkable polyvinyl chloride sheet was bonded to the surface from which the surface coating material 69 was removed using an epoxy-based adhesive. Then 60
The polyvinyl chloride was shrunk by applying heat of ° C., and the optical fibers from which the surface coating material 69 had been removed by the shrinkage were brought into close contact with each other to perform bonding. Finally, the polyvinyl chloride sheet was peeled off from the fiber tip, and both end faces of the optical fiber bundle were optically polished using alumina. The product obtained in Experimental Example 3 is referred to as Sample 3.

(Experimental Example 4) (See FIG. 15) The sample 3 obtained in Experimental Example 3 was introduced with the light of an ultra-high pressure mercury lamp from the surface where the distance between the center positions of the optical fiber sections of adjacent optical fibers was short. When immersed in a photocurable resin mixture liquid 72 of phenoxyethyl acrylate, the curing reaction proceeded by a photopolymerization reaction, and a tapered fiber was self-formed at 2 mm in the initial stage of the reaction, and finally the fiber diameter became 200 μm. After forming the tapered fiber, the resin in the uncured portion was removed with acetone, and the clad layer was formed by thermosetting a fluorinated epoxy having a refractive index higher than that of the photocurable resin. Finally, the optical fiber surface formed into a tapered shape was optically polished using alumina. The product obtained in Experimental Example 4 is referred to as Sample 4.

(Evaluation Results of Prepared Samples) FIG. 17 is a table showing the evaluation results of the samples of the present invention. The characteristics of the sample thus prepared as a magnifying optical device for a light emitting device (the ratio of the amount of light emitted to the magnifying surface to the amount of light irradiated to the reducing surface; FIG. 17)
Then, the light transmission efficiency is expressed in%. ), The characteristics as a magnifying optical device for a reflective device (the ratio of the amount of light emitted to the reducing surface to the amount of light irradiated to the magnifying surface. In FIG. 17, the reflection efficiency is expressed as%), the image magnification, and the area of the magnifying surface. , Device thickness, device weight, and the above six items were evaluated as device characteristics. For comparison with the prior art, the above-mentioned characteristics of a magnifying optical device “TaperMag” Pocket Type manufactured by Taper Vision Inc., in which glass fibers are bundled, melted and stretched, were evaluated as comparative examples. The results are shown in FIG.

As can be seen from the evaluations of Experimental Examples 1 to 4 and Comparative Example (conventional example), despite the fact that the area of the enlarged surface is larger than that of Comparative Example, the device weight of the present invention is smaller than that of the conventional device. Thus, a transmission-type magnifying optical device having a very light, thin device thickness and a high magnifying power was realized. As is clear from the comparison between Experimental Example 1 and Experimental Example 2 and between Experimental Example 3 and Experimental Example 4, the optical fiber near the enlarged surface has a tapered shape, and the cross-sectional area of the optical fiber on the enlarged surface is increased. As a result, it was possible to obtain excellent characteristics as a reflection-type magnifying optical device. Furthermore, as is clear from the comparison between Experimental Examples 1 and 3, and between Experimental Examples 2 and 4, by increasing the density of the cross section of the optical fiber on the reduced surface, the magnifying optics with high light transmission efficiency can be obtained. The device has been realized. The light transmission efficiency and the reflection efficiency of the experimental examples 3 and 4 are higher than that of the comparative example using the glass fiber because the device thickness can be made thinner than that of the comparative example. It is considered that light transmission loss in the optical fiber was reduced.

[0034]

As described above, according to the present invention,
(Claim 1) An inexpensive two-dimensional enlargement / reduction optical device can be realized by using an aggregate of light guide paths made of a polymer optical fiber as a raw material. (Claim 2) Since the end surfaces of the plurality of polymer optical fibers on the enlarged surface are located substantially on one plane and the end surfaces on the reduced surface are also located substantially on one plane, transmission of a planar image can be achieved. realizable. (Claim 3)
Since the relative position of the end face of the polymer optical fiber with respect to the adjacent polymer fiber is maintained also at the other end face, transmission of a two-dimensional image can be realized.
(Claim 4) The relative distance between the cross-sectional center position on the enlarged surface of the high-refractive-index region and the cross-sectional center position on the enlarged surface of another adjacent high-refractive-index region is different from the cross-sectional center position on the reduced surface. A thin, high-magnification two-dimensional enlargement / reduction optical device can be realized without using a lens or the like by being larger than the relative distance of the cross-sectional center position on the reduction surface of another high refractive index region adjacent thereto. Can be.

(Claim 5) By using a foamed material as a means for keeping the relative position between the high refractive index regions constant, the center position of the cross section on the enlarged surface and the other high refractive index regions adjacent thereto can be reduced by an inexpensive method. The relative distance between the cross-sectional center position on the enlarged surface and the cross-sectional center position on the reduced surface of the other high-refractive-index area adjacent to it can be made larger than the relative distance between the cross-sectional center position on the reduced surface. it can. (Claim 6) By using a foamed material as a member for keeping the relative position between the high refractive index regions constant, a means for increasing the distance between the polymer fibers and a means for maintaining the distance after lengthening are provided. Since both devices can be used, an inexpensive device can be realized. (Claim 7) By using the foaming material only in the region near the enlarged surface of the high refractive index region, the amount of the foaming agent used as a raw material can be reduced. (Claim 8) When the foam material expands by not having or weakening the adhesiveness of the surface coating material covering the polymer optical fiber to the fiber, the fiber preform expands the foam material. Can move through the coating material in accordance with

(Claim 9) Since the relative positional relationship between the adjacent surface coating materials is kept constant, even if the foaming agent expands and the fiber moves in the coating material, the relative position between the adjacent fibers is maintained. It is possible to maintain a proper positional relationship. (Claim 10) Since the surface coating material is a material that can be bonded to an adjacent surface coating material, the relative positional relationship between the fiber surface coating materials can be kept constant by an inexpensive method.
(Claim 11) The cross section of the light guide path made of a polymer optical fiber has a substantially constant cross-sectional area from the plate reduction surface to the vicinity of the plate enlargement surface, and in the vicinity of the enlargement surface, the light guide becomes closer to the enlargement surface. By increasing the cross-sectional area of the optical path, a bright two-dimensional image can be transmitted even when the image of the reflection type device is enlarged / reduced, and the volume of each polymer optical fiber can be minimized. For,
An optical device with a small weight can be realized. (Claim 12) Since the ratio of the cross-sectional area of the light guide path on the enlargement plane to the cross-sectional area of the light guide path on the reduction plane is almost the same value, enlargement / reduction of an image with less distortion can be realized.

(13) The light guide path portion having a larger cross-sectional area near the magnifying surface as it approaches the magnifying surface is formed at a stage after the foaming material foams, so that the cross-sectional area of the light guide path increases. Even so, interference with an adjacent light guide path can be avoided. (Claim 14) The light guide path portion, whose cross-sectional area increases as approaching the enlarged surface, is a photo-curable resin formed by immersing one end of a polymer optical fiber in a photo-curable resin mixed liquid and entering light from the other end. Thus, the tapered light guide path can be formed by an inexpensive method. (Claim 15) An aggregate of light guide paths is formed in advance as an aggregate of a plurality of polymer optical fibers as one block, and then formed as an aggregate of a plurality of block units. The assembly of light guide paths can be manufactured by a method suitable for mass production. (Claim 16) Since the cross-sectional shape of the block is approximately square, a very large number of light guide paths can be manufactured by a method suitable for mass production without leaving a gap between the blocks. . (Claim 17) Since the cross-sectional shape of the block is approximately hexagonal, a very large number of light guide path aggregates can be manufactured by a method suitable for mass production without opening a gap between the blocks. . (Claim 18) By shortening the distance between adjacent optical fibers on the reduction plane by using a shrinking material, the packing density of the optical fiber cross section on the reduction plane can be increased, and the light of the image on the enlargement plane can be increased. Transmission efficiency can be improved. (Claim 19) By using a heat-shrinkable polymer sheet as a shrinkable material, it is possible to increase the packing density of the cross section of the optical fiber on the reduced surface by an inexpensive method and improve the light transmission efficiency of an image to the enlarged surface.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a method A of a conventional enlarged optical device.

FIG. 2 is a cross-sectional view showing a method B of a conventional magnifying optical device.

FIG. 3 is a block diagram showing a method C of a conventional magnifying optical device.

FIG. 4 is a cross-sectional view showing a method D of a conventional magnifying optical device.

FIG. 5 is a basic structural diagram of a two-dimensional scaling optical device according to a first embodiment of the present invention;

FIG. 6 is a perspective view of the optical device in FIG. 5;

FIG. 7 is a basic structural diagram of a two-dimensional scaling optical device according to a second embodiment of the present invention.

FIG. 8 is a partially enlarged view of a polymer optical fiber coated with a surface coating material according to the present invention.

FIG. 9 is a perspective view of a block in which polymer optical fibers according to the present invention are bundled.

FIG. 10 is a perspective view of a block in which a plurality of blocks shown in FIG. 9 are stacked and bundled.

11 is a partially enlarged view of FIG. 10, showing a step of removing a fiber surface coating material.

FIG. 12 is a partially enlarged view of FIG. 10, showing a step of applying a foaming agent to one end of the optical fiber.

FIG. 13 is a partially enlarged view of FIG. 10, showing a step of foaming a foaming agent.

FIG. 14 is a partially enlarged view of FIG. 10, showing a step of cutting the opposite end surface.

FIG. 15 is a diagram showing a step of adding a taper to the optical fiber according to the present invention.

FIG. 16 is a view showing a step of bonding a shrinkable material to another end of the optical fiber according to the present invention.

FIG. 17 is a table diagram of evaluation results of samples created by an experimental example of the present invention.

[Explanation of symbols]

51: enlarged surface holding material, 52: enlarged surface, 53: polymer optical fiber, 54: reduced surface holding material, 56: polymer optical fiber taper portion, 61: polymer optical fiber covered with a surface coating material, 62
... Partial enlarged view, 63 ... Surface coating material, 64 ... Block bundled with polymer optical fibers, 65 ... Block bundled with plural blocks, 66 ... Coating material, 67 ... Foaming agent, 68 ... From sheath of surface coating material An optical fiber that has slid out, 69: a fiber coated with a coating material, 70: ultraviolet irradiation, 71: a tapered light guide path portion, 72: an ultraviolet curable resin mixture, 73: a shrinkable material.

[Procedure amendment]

[Submission date] August 29, 2000 (2008.2.
9)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H046 AA03 AA09 AA32 AA65 AB01 AC28 AD13 AZ08 5C058 EA04 5G435 AA17 AA18 DD02 FF02 FF08 HH01 KK07

Claims (19)

[Claims] 1. A device in which a plurality of high refractive index regions having a high refractive index are formed, wherein each of the high refractive regions is formed of one polymer optical fiber, and the device is formed of a polymer optical fiber. A two-dimensional enlargement / reduction optical device characterized by being constituted by an assembly of light guide paths. 2. The two-dimensional expansion / reduction optical device according to claim 1, wherein one end face of the polymer optical fiber constituting the aggregate of the light guide paths is located substantially on one plane, and the polymer light is arranged. A two-dimensional scaling optical device, characterized in that the other end face of the fiber is also substantially on one plane. 3. The two-dimensional expansion / reduction optical device according to claim 2, wherein the relative position of the end face of the polymer optical fiber with respect to the adjacent polymer fiber is the other end of the polymer optical fiber. A two-dimensional enlargement / reduction optical device characterized in that the two-dimensional enlargement / reduction optical device is maintained at the end face of the optical device. 4. The two-dimensional enlargement / reduction optical device according to claim 3, wherein a cross-sectional center position on an enlargement surface which is one end surface of the polymer optical fiber and an enlargement of another polymer optical fiber adjacent thereto. The relative distance of the cross-sectional center position on the plane is the difference between the cross-sectional center position on the reduced plane that is the other end face of the polymer optical fiber and the cross-sectional center position on the reduced plane of another polymer optical fiber adjacent thereto. A two-dimensional scaling optical device characterized by being greater than a relative distance. 5. The two-dimensional expansion / reduction optical device according to claim 4, wherein a center position of a cross section of one of the polymer optical fibers on an enlarged surface and a cross section of another polymer optical fiber adjacent thereto on the enlarged surface. The relative distance between the center positions is larger than the relative distance between the cross-sectional center position on the other reduced surface of the polymer optical fiber and the cross-sectional center position on the reduced surface of another polymer optical fiber adjacent thereto. A two-dimensional enlargement / reduction optical device, characterized by using a foam material as a means for performing the operation. 6. The two-dimensional enlargement / reduction optical device according to claim 4, wherein a part of the member for keeping the relative position of the polymer optical fiber constant is a foam material. Devices. 7. The two-dimensional enlargement / reduction optical device according to claim 6, wherein the foam material is used only in a region near an enlargement surface of a high refractive index region. Devices. 8. The method for manufacturing a two-dimensional enlarged / reduced optical device according to claim 1, wherein at least before the foamed material according to claim 5 foams, the polymer optical fiber is A method for producing a two-dimensional scaling optical device, characterized in that the device has no adhesion to an optical fiber or is coated with a surface coating film having low adhesion. 9. The method for manufacturing a two-dimensional scaling optical device according to claim 8, wherein the surface coating material is positioned relative to an adjacent surface coating material from one end to the other end. A method for manufacturing a two-dimensional enlargement / reduction optical device, wherein the relationship is kept constant. 10. The method of manufacturing a two-dimensional scaling optical device according to claim 8, wherein the surface coating material is a material that can be bonded to an adjacent surface coating material. Manufacturing method. 11. The two-dimensional scaling optical device according to claim 1, wherein a cross section of the light guide path made of the polymer optical fiber is substantially from the reduction surface according to claim 4 to the vicinity of the expansion surface. A two-dimensional enlargement / reduction optical device having a constant cross-sectional area, wherein the cross-sectional area increases in the vicinity of the enlargement plane as it approaches the enlargement plane. 12. The two-dimensional magnification / reduction optical device according to claim 11, wherein a ratio of a cross-sectional area of the light guide path on the enlargement surface to a cross-sectional area of the light guide path on the reduction surface is a plurality of high refractive index regions. A two-dimensional scaling optical device, characterized in that they have substantially the same value. 13. The two-dimensional scaling optical device according to claim 11, wherein the light guide path portion is in the vicinity of the enlarged surface whose cross-sectional area increases as approaching the enlarged surface. A two-dimensional enlargement / reduction optical device formed at a stage after foaming of a foamed material. 14. The two-dimensional expansion / reduction optical device according to claim 11, wherein in the vicinity of the enlarged surface whose cross-sectional area increases as approaching the enlarged surface, one end of the polymer optical fiber is made of a photocurable resin. A two-dimensional enlargement / reduction optical device characterized by using a photocurable resin material prepared by immersing in a mixed liquid and allowing light to enter from the other end as a raw material. 15. The two-dimensional expansion / reduction optical device according to claim 8, wherein the polymer optical fiber covered with the surface coating material is formed in advance as an aggregate of a plurality of polymer optical fibers as one block. A two-dimensional enlargement / reduction optical device formed as an aggregate comprising a plurality of block units. 16. The two-dimensional enlargement / reduction optical device according to claim 15, wherein a cross-sectional shape of the block is substantially a quadrangle. 17. The two-dimensional scaling optical device according to claim 15, wherein a cross-sectional shape of the block is substantially hexagonal. 18. The two-dimensional expansion / reduction optical device according to claim 4, wherein a relative center distance between a cross-sectional center position on the reduced surface and a cross-sectional center position on a reduced surface of another polymer optical fiber adjacent thereto. A two-dimensional enlargement / reduction optical device, characterized in that a shrinkable material is used as means for reducing the size. 19. The two-dimensional scaling optical device according to claim 18, wherein the shrinkable material is a heat-shrinkable sheet.