JP3635879B2 - Optical data bus and signal processing apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical data bus responsible for propagation of an optical signal, and a signal processing apparatus that performs signal processing including transmission and reception of data using the optical data bus.
[0002]
[Prior art]
With the development of very large scale integrated circuits (VLSI), the circuit functions of circuit boards (daughter boards) used in data processing systems have increased significantly. As the number of circuit functions increases, the number of signal connections to each circuit board increases. Therefore, a data bus board (motherboard) that connects each circuit board (daughter board) with a bus structure requires a large number of connection connectors and connection lines. A parallel architecture has been adopted. Although parallel buses have been improved by increasing the number of connection lines and making them parallel, the operation speed of parallel buses has been improved. However, the processing speed of the system is increased in parallel due to signal delays due to the capacitance between connection lines and connection line resistance. It may be limited by the operating speed of the bus. Further, the problem of electromagnetic noise (EMI) due to the high density of parallel bus connection wiring is also a major limitation on the improvement of the processing speed of the system.
[0003]
In order to solve such a problem and improve the operation speed of the parallel bus, it has been studied to use an intra-system optical connection technique called optical interconnection. The outline of the optical interconnection technology is described in “Koji Uchida, 9th Circuit Implementation Conference 15C01, pp. 201-202 "and" H. Tomimura et al. "Packaging Technology for Optical Interconnects", IEEE Tokyo No. 33 pp. 81-86, 1994 ", Osamu Wada, Electronics April 1993, pp. 52-55 ”, various types of technologies have been proposed depending on the contents of the system configuration.
[0004]
[Problems to be solved by the invention]
Among various types of conventionally proposed optical interconnection technologies, Japanese Patent Application Laid-Open No. 2-41042 discloses an example in which an optical data transmission method using a high-speed, high-sensitivity light emitting / receiving device is applied to a data bus. The light emitting / receiving devices are arranged on both the front and back surfaces of each circuit board, and the light emitting / receiving devices on the adjacent circuit boards incorporated in the system frame are spatially coupled by light. A serial optical data bus for loop transmission between circuit boards has been proposed. In this method, the signal light sent out from a certain circuit board is optical / electrically converted by the adjacent circuit board, and then this electric / optical conversion is then performed by the circuit board, and then to the adjacent circuit board. As the signal light is sent out, each circuit board is sequentially arranged in series and transmitted between all circuit boards incorporated in the system frame while repeating optical / electrical conversion and electrical / optical conversion on each circuit board. For this reason, the signal transmission speed depends on the light / electric conversion speed and the electric / light conversion speed of the light receiving / light emitting device arranged on each circuit board, and at the same time, is restricted. In addition, data transmission between circuit boards uses optical coupling with free space by light receiving / light emitting devices arranged on each circuit board, so it is arranged on both sides of adjacent circuit boards. The light emitting / receiving device is optically aligned and all circuit boards must be optically coupled. Furthermore, since each circuit board is coupled through a free space, interference (crosstalk) between adjacent optical data transmission paths occurs, and data transmission failure is expected. It is also expected that a data transmission failure will occur due to the diffusion of signal light due to the environment in the system frame, such as dust. Furthermore, since the circuit boards are arranged in series, if any of the boards is removed, the connection is interrupted there, so that an extra circuit board is required to make up for it. That is, there is a problem that the circuit boards cannot be freely attached and detached, and the number of circuit boards is fixed.
[0005]
In addition to these, as a data transmission technique between circuit boards using free space, Japanese Patent Application Laid-Open No. 61-196210 includes a plate having two parallel surfaces and facing a light source. Has disclosed a system for optically coupling circuit boards through an optical path constituted by a diffraction grating and a reflective element arranged in the above. In this method, there is a problem that light emitted from one point can be transmitted to only one fixed point, and all circuit boards cannot be comprehensively connected like an electric bus. In addition, since a free optical space is used, a complicated optical system is required, and alignment is difficult. Therefore, interference (crosstalk) between adjacent optical transmission paths due to the displacement of the optical element occurs, Data transmission failure is expected. Furthermore, since the connection information between the circuit boards is determined by the diffraction grating and the reflective element arranged on the plate surface, there are various problems such that the circuit boards cannot be freely inserted and removed and the expandability is low.
[0006]
In view of the above circumstances, the present invention is an optical data bus that is highly resistant to dust and the like, is resistant to environmental changes such as temperature changes, and can easily be attached and detached freely according to the expandability of the system. An object of the present invention is to provide a signal processing device employing an optical data bus.
[0007]
[Means for Solving the Problems]
As a means to achieve the above object, it is conceivable to adopt a sheet-like optical bus that diffuses and propagates the incident signal light, but if such an optical bus is simply produced, depending on the incident position of the signal light, There is a possibility that the intensity of signal light emitted from a single emission position varies greatly, and it is necessary to detect signal light having a wide dynamic range. For this reason, it is necessary to perform circuit design adapted to the wide dynamic range, but circuit design adapted to the wide dynamic range is difficult, and there is a problem in that the S / N is reduced and the cost is increased.
[0008]
Accordingly, an optical bus of the present invention is an optical bus that achieves the above-described object and further reduces a change in the intensity of the emitted signal light depending on the incident position and the outgoing position of the signal light. 1 optical data bus
A signal light incident part that is responsible for the incidence of signal light along one edge, and a signal light emission part that is responsible for the emission of signal light along the edge opposite to the one edge, and A sheet-like optical data bus that propagates signal light incident from a signal light incident part and emits the signal light from the signal light output part, wherein the signal light incident part is close to one side surface of the one end edge. Refracting means for refracting the signal light incident from a certain position in a direction away from the one side surface, and diffusing means for diffusing the refracted signal light inside the optical data bus.
[0009]
The second optical data bus of the present invention is
A signal light incident part that is responsible for the incidence of signal light along one edge, and a signal light emission part that is responsible for the emission of signal light along the edge opposite to the one edge, and A sheet-like optical data bus that propagates the signal light incident from the signal light incident part and emits the signal light from the signal light emission part, on both sides of the optical data bus, from the inside of the optical data bus to this side It has a reflection suppressing portion that suppresses reflection of incident signal light into the optical data bus.
[0010]
The first signal processing device of the present invention is:
(1) Base
(2) A signal light emitting end for emitting signal light, a circuit for generating a signal to be carried on the signal light emitted from the signal light emitting end, a signal light incident end for entering the signal light, and the signal light incident end A plurality of circuit boards on which at least one of a circuit for performing signal processing based on a signal carried by incident signal light is mounted
(3) A signal light incident part that is responsible for the incidence of signal light along one edge and a signal light emission part that is responsible for the emission of signal light along the edge opposite to the one edge. And a sheet-like optical data bus that propagates the signal light incident from the signal light incident part and emits the signal light from the signal light output part, and the signal light incident part has one edge of the one edge. An optical data bus comprising refracting means for refracting signal light incident from a position close to the side face in a direction away from the one side face, and diffusing means for diffusing the refracted signal light inside the optical data bus
(4) The circuit board is placed on the substrate in a state where the signal light emitting end or signal light incident end mounted on the circuit board is coupled to the optical data bus at the signal light incident part or signal light emitting part. Multiple board fixing parts to fix
It is provided with.
[0011]
The second signal processing apparatus of the present invention is
(1) Base
(2) A signal light emitting end for emitting signal light, a circuit for generating a signal to be carried on the signal light emitted from the signal light emitting end, a signal light incident end for entering the signal light, and the signal light incident end A plurality of circuit boards on which at least one of a circuit for performing signal processing based on a signal carried by incident signal light is mounted
(3) A signal light incident part that is responsible for the incidence of signal light along one edge and a signal light emission part that is responsible for the emission of signal light along the edge opposite to the one edge. A sheet-like optical data bus that propagates the signal light incident from the signal light incident part and emits the signal light from the signal light emission part, and is formed on both side surfaces of the optical data bus from the inside of the optical data bus. An optical data bus having a reflection suppression unit that suppresses reflection of signal light incident on the side surface into the optical data bus.
(4) The circuit board is placed on the substrate in a state where the signal light emitting end or signal light incident end mounted on the circuit board is coupled to the optical data bus at the signal light incident part or signal light emitting part. Multiple board fixing parts to fix
It is provided with.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described.
FIG. 1 is a plan view showing an optical data bus according to the first embodiment of the present invention.
The optical data bus 10 includes a signal light incident portion 11 that is responsible for the incidence of signal light along one edge, and a signal light that is responsible for emission of the signal light along an edge opposite to the one edge. This is an optical data bus in the form of a sheet that has an emission part 14, propagates the signal light incident from the signal light incident part 11 and emits the signal light from the signal light emission part 14.
[0013]
The optical data bus 10 body is an optical transmission layer 16 that propagates the signal light incident from the signal light incident portion 11 toward the signal light emitting portion 14, and one end face of the optical transmission layer 16 has a curvature. ing. In the first embodiment, this one end surface is formed in an arc shape centered on a point equidistant from the side surfaces 17 and 18 of the end surface 15 of the optical data bus 10 to have a curvature. The signal light incident portion 11 includes a light diffusion layer 12 that diffuses the incident signal light into the light transmission layer 16. The light diffusion layer 12 is bonded to an end surface of the light transmission layer 16 having a curvature. ing. The shape of the end surface 13 of the optical data bus 10 on the light diffusion layer 12 side is the same as the shape of the end surface of the optical transmission layer 16 to which the light diffusion layer 12 is bonded. The arc shape is centered on a point that is equidistant from 17 and 18, and the end surface of the optical data bus 10 on the signal light incident portion 11 side has a curvature. As described above, the signal light incident portion 11 has the end surface 13 having a curvature and further includes the light diffusion layer 12, so that the signal incident from a position close to one of the side surfaces 17 and 18 is input. The light is refracted in a direction away from the one side surface, and the refracted signal light is diffused into the optical transmission layer 16.
[0014]
A plurality of light emitting elements (three light emitting elements 19, 20, and 21 are shown in FIG. 11) are arranged along the end surface 13 of the optical data bus 10 on the signal light incident portion 11 side, and the signal of the optical data bus 10 is displayed. A plurality of light receiving elements (three light receiving elements 22, 23, 24 are shown in this figure) are arranged along the end face 15 on the light emitting part 14 side, and when signal light is emitted from each light emitting element, The signal light enters the signal light incident portion 11, is diffused toward the optical transmission layer 16 by the light diffusion layer 12 provided in the signal light incident portion 11, and propagates through the optical transmission layer 16. Are emitted from the end face 15 on the signal light emitting part 14 side and received by each light receiving element.
[0015]
The optical transmission layer 16 of the optical data bus 10 has a length of 150 mm and a thickness of 1 mm on both sides and the signal light emitting part 14 side, and the signal light incident part 11 side is formed in an arc shape. Polymethylmethacrylate). The light diffusion layer 12 bonded to the end face of the light transmission layer 16 is a light diffusion film produced by forming an acrylic resin layer having a thickness of 10 μm mixed with a silica pigment on a polyester film. And the diffusion properties of this light diffusion film are approximately equal to the complete diffusion distribution. The light emitting element is a laser diode having an oscillation wavelength of 680 nm and an output intensity of 3 mW, and the light receiving element is a Si photodiode having a light receiving diameter of 0.7 mm.
[0016]
In the optical data bus 10 configured in this way, the end surface 13 on the signal light incident part 11 side is formed in an arc shape, so that one side surface (side face 17 to side face 18) of the signal light incident part 11 is formed. The signal light incident from the approached position is refracted in a direction away from the one side surface, that is, in a direction toward the central portion of the signal light emitting portion 14, and the refracted signal light is diffused by the light diffusion layer 12. The diffusion characteristics of the light diffusion layer 12 are substantially equal to the perfect diffusion characteristics, and the signal light having the highest intensity among the signal lights diffused by the light diffusion layer 12 propagates toward the central portion of the signal light emitting section 14. . Therefore, for example, when the signal light emitted from the light emitting element 19 enters the signal light incident portion 11, the signal light 25 having the highest intensity among the signal light diffused by the light diffusion layer 12 is transmitted to the signal light emitting portion 14. Propagates toward the center of
[0017]
Hereinafter, the operation of the optical data bus 10 shown in FIG. 1 will be described in comparison with the operation of the optical data bus in which the signal light incident portion has no curvature.
FIG. 2 is a plan view showing an optical data bus in which the signal light incident part has no curvature.
In the description of this figure, the same components as those shown in FIG. 1 are denoted by the same reference numerals, and only differences from FIG. 1 will be described.
[0018]
The difference between the optical data buses 10 and 100 shown in FIGS. 1 and 2 is that the end face of the optical transmission layer 16 provided in the optical data bus 100 shown in FIG. 100, the end face 13 of the optical data bus 100 is also formed in parallel with the end face 15. Therefore, the end face 13 of the optical data bus 100 has no curvature, The optical data bus 100 shown in FIG. 2 refracts the signal light incident from the position close to one side surface of the optical data bus 10 shown in FIG. 1 away from the one side surface. There is no refracting means to be provided.
[0019]
When the signal light incident on the signal light incident portion 11 of the optical data bus 100 shown in FIG. 2 is diffused by the light diffusion layer 12, the diffused signal light exhibits almost perfect diffusion characteristics. Of the diffused signal light, the signal light having the highest intensity travels parallel to the side surfaces 17 and 18, so that the signal light 26 is emitted from the light emitting element 19 located at one side of the optical data bus 100. When emitted, the signal light 27 having the highest intensity among the signal lights diffused by the light diffusion layer 12 is emitted from a position near the side surface 17 of the signal light emitting unit 14. A part of the signal light diffused by the light diffusion layer 12 propagates toward the side surfaces 17 and 18, but the signal light propagates to the side surface 17 at an incident angle larger than the critical angle with respect to the signal light toward the side surface 17. 28 is totally reflected by the side surface 17 and is emitted from a position of the signal light emitting portion 14 near the side surface 17.
[0020]
Therefore, when signal light is emitted from the light emitting element 19 shown in FIG. 2, the intensity of the signal light emitted from the position near the side surface 17 of the signal light emitting unit 14 is large, and the side surface 18 of the signal light emitting unit 14 is large. The intensity of the signal light emitted from the position close to is small. That is, the intensity of the signal light emitted from the signal light emitting unit 14 varies greatly in the arrangement direction of the light receiving elements shown in FIG. 2, and the intensity of the signal light received by the light receiving elements located near the side surface 17 is large. The intensity of the signal light received by the light receiving element located near the side surface 18 is small.
[0021]
In addition, when signal light is emitted from the light emitting element 21 shown in FIG. 2, the signal light received by the light receiving element at a position close to the side surface 17 is opposite to when signal light is emitted from the light emitting element 19. The intensity is small, and the intensity of the signal light received by the light receiving element located near the side surface 18 is large.
That is, when signal light is emitted from a certain light emitting element, the intensity of the signal light emitted from the signal light emitting unit 14 varies in the arrangement direction of the light receiving elements shown in FIG. When attention is paid to one of the light receiving elements arranged along the line, the intensity of the signal light received by the light receiving element varies greatly depending on the position of the light emitting element that emits the signal light.
[0022]
On the other hand, in the optical data bus 10 shown in FIG. 1, the signal light 25 having the highest intensity among the signal lights diffused by the light diffusion layer 12 is directed toward the central portion of the signal light emitting unit 14 as described above. In order to propagate, for example, when signal light is emitted from the light emitting element 19, the signal light emitted from the position close to the side surface 17 of the signal light emitting unit 14 is compared with the optical data bus 100 shown in FIG. 2. The intensity is reduced, and the intensity of the signal light emitted from the position of the signal light emitting portion 14 near the other side surface 18 opposite to the side surface 17 is increased. For this reason, the variation in the intensity of the signal light emitted from the signal light emitting unit 14 in the arrangement direction of the light receiving elements is reduced. Therefore, when the optical data bus 10 emits signal light from a certain light emitting element, variation in the signal light received by each light receiving element is suppressed, so that the optical data bus 10 has different light emitting elements. Even if signal light is incident from (for example, the light emitting elements 19 and 21), variation in intensity of signal light received by a certain light receiving element due to the light emitting element is suppressed.
[0023]
Further, the optical data bus 10 shown in FIG. 1 has a light diffusion layer 12, and the incident signal light is diffused and propagated. Therefore, the signal light incident from the signal light incident portion 11 is surely received even if there is a temperature change or the like. Are emitted from the signal light emitting portion 14. Further, at least one of the light emitting element and the light receiving element is mounted on a circuit board, and the element mounted on the circuit board is disposed at a position optically coupled to the optical data bus. When the circuit board is configured to be detachably mounted, the optical coupling between the element mounted on the circuit board and the optical data bus is completed simply by mounting the circuit board. Between the optical data bus and the number of circuit boards that are optically coupled to the optical data bus is within the maximum number of circuit boards that are optically coupled to the optical data bus. The system can be increased or decreased, and a highly flexible system rich in expandability can be constructed.
[0024]
The light diffusion layer 12 included in the optical data bus 10 shown in FIG. 1 is formed by forming an acrylic resin layer mixed with a silica pigment on a polyester film. As long as the refractive indexes are different from each other, the combination of the pigment material and the resin layer material is arbitrary, and as the pigment, rutile, zinc white, etc. can be applied in addition to silica, and the resin layer can be other than acrylic. Epoxy and the like can be applied.
[0025]
In addition, a light diffusing film is used for the light diffusing layer 12, but any light diffusing film may be used as long as it exhibits a light diffusing action. For example, a liquid crystalline polymer layer solidified in a random alignment state is used. Alternatively, the end surface of the optical data bus on the signal light incident portion side may be roughened by a sandblast method or the like.
FIG. 3 is a plan view showing an optical data bus according to the second embodiment of the present invention.
[0026]
In the description of FIG. 3, the same components as those shown in FIG. 1 are denoted by the same reference numerals as those shown in FIG. 1, and only differences from FIG. 1 will be described.
The signal light incident portion 31 provided at one end edge of the optical data bus 30 shown in FIG. 3 enters the signal light incident from a position near one side surface (side surface 37 to side surface 38) of this one end edge. Is refracted in a direction away from the one side surface, and the light diffusion layer 33 diffuses the signal light refracted by the signal light refractor 32 into the light transmission layer 16 so as to have directivity. And. The optical transmission layer 16 included in the optical data bus 30 has a square shape, and the light diffusion layer 33 provided in the signal light incident portion 31 is bonded to the end face of the optical transmission layer 16. The light diffusing layer 33 is optically coupled to the signal light refracting unit 32 with air interposed therebetween, and an end surface 35 of the signal light refracting unit 32 facing the light diffusing layer 33 is connected to the optical data bus 30. The end surface 15 of the signal light emitting part 14 side is formed in an arc shape centered on a point equidistant from the side surfaces 37 and 38.
[0027]
The signal light refracting section 32 provided in the signal light incident section 31 of the optical data bus 30 is made of PMMA having an end surface facing the light diffusion layer 33 formed into an arc shape.
In the optical data bus 30 configured as described above, the end surface 35 of the signal light refracting unit 32 facing the light diffusion layer 33 is formed in an arc shape as described above. When the signal light is incident from a position close to one of the side surfaces (side surface 37 to side surface 38), the signal light emitted from the signal light refracting unit 32 is separated from the one side surface, that is, the signal light emitting unit 14. The light is refracted in the direction toward the central portion, and the refracted signal light is diffused by the light diffusion layer 33.
[0028]
4 and 5 are diagrams for explaining the operation of the light diffusion layer shown in FIG.
The left side of the light diffusion layer 33 shown in FIGS. 4 and 5 is air interposed between the light diffusion layer 33 and the signal light refraction part 32.
As shown in FIG. 4, when the signal light 39 is incident on the light diffusion layer 33 perpendicular to the end face 36 of the light diffusion layer 33, the signal light diffused by the light diffusion layer 33 has the highest intensity. The signal light 40 propagates perpendicularly to the end face 36 of the light diffusion layer 33.
[0029]
Further, as shown in FIG. 5, when the signal light 41 is incident on the light diffusion layer 33 at an incident angle of, for example, 30 degrees with respect to the end surface 36 of the light diffusion layer 33, the signal light diffused by the light diffusion layer 33. Among them, the signal light 42 having the highest intensity propagates in the same direction as the propagation direction of the signal light 41.
Therefore, when the signal light refracted by the signal light refracting unit 32 enters the light diffusion layer 33, the signal light having the highest intensity among the signal light diffused by the light diffusion layer 33 is refracted by the signal light refracting unit 32. It propagates in the same direction as the propagation direction of the signal light. In the optical data bus 30 shown in FIG. 3, the signal light refracted by the signal light refracting unit 32 propagates toward the central portion of the end surface 15 of the signal light emitting unit 14. Among them, the signal light having the highest intensity propagates toward the central portion of the end face 15 of the optical data bus 30.
[0030]
Therefore, when signal light is incident on the optical data bus 30 shown in FIG. 3 from a position close to one side surface (for example, the side surface 37), as in the optical data bus shown in FIG. The intensity of the signal light emitted from the position close to the side surface 37 becomes small, and the intensity of the signal light emitted from the position close to the other side face 38 of the signal light emitting portion 14 opposite to the side face 37 is growing. For this reason, the variation in the intensity of the signal light emitted from the signal light emitting unit 14 in the arrangement direction of the light receiving elements is reduced. Therefore, when the signal light is emitted from a certain light emitting element, the optical data bus 10 suppresses the variation of the signal light received by each light receiving element, whereby different light emitting elements are connected to the optical data bus 30. Even if signal light is incident from (for example, the light emitting elements 19 and 21), variation in intensity of signal light received by a certain light receiving element due to the light emitting element is suppressed.
[0031]
In the optical data bus 30 shown in FIG. 3, the signal light incident on the signal light incident part 31 is refracted by forming the end surface 35 of the signal light refracting part 32 facing the light diffusion layer 33 in an arc shape. However, instead of forming the end surface 35 of the signal light refracting portion 32 facing the light diffusing layer 33 in an arc shape, for example, the end surface of the signal light refracting portion facing the light diffusing layer is refracted by signal light. The signal light incident on the signal light incident part may be refracted by forming a set of a plurality of planes having different angles with respect to the propagation direction of the signal light propagating from the inside of the part toward the end face.
[0032]
FIG. 6 is a plan view showing an optical data bus according to the third embodiment of the present invention.
In the description of FIG. 6, the same components as those illustrated in FIG. 1 are denoted by the same reference numerals as those illustrated in FIG. 1, and only differences from FIG. 1 will be described.
The optical transmission layer 16 included in the optical data bus 50 shown in FIG. 6 has a square shape, and the optical data bus 50 is incident on both sides thereof from the inside of the optical data bus 50 to the side surface of the optical data bus 50. Light absorption layers 51 and 52 that absorb signal light are provided. The light absorption layers 51 and 52 are formed by applying an acrylic resin in which a black pigment is dispersed on the side surface of the light transmission layer 16.
[0033]
When the light absorption layers 51 and 52 are provided on both side surfaces of the optical data bus 50 as described above, the signal light propagating toward the light absorption layers 51 and 52 is absorbed by the light absorption layers 51 and 52. Reflection of signal light on the side surface is suppressed.
In the optical data bus 100 illustrated in FIG. 2, when signal light is incident from a position close to one side surface (for example, the side surface 17) of the signal light incident unit 11, The signal light having the highest intensity that propagates directly toward the signal light emitting portion 14 without being reflected by the side surfaces 17 and 18 is emitted from a position near the side surface 17 of the signal light emitting portion 14, and the light. Of the signal light diffused by the diffusion layer 12, most of the signal light totally reflected by the side surface 17 is emitted from a position near the one side surface of the signal light emitting unit 14. The intensity of the signal light emitted from the position near the one side surface of the portion 14 is the signal emitted from the position near the other side surface of the signal light emitting portion 14 opposite to the one side surface. Although it is larger than the intensity of light, the optical data shown in FIG. Scan 50, since the both sides has a light absorbing layer 51, reflection of signal light at this side is suppressed. Therefore, the optical data bus 50 shown in FIG. 6 is one of the signal light emitting portions of the optical data bus 50 even if the signal light is incident from a position close to one side as compared with the optical data bus 100 shown in FIG. The intensity of the signal light emitted from the position close to the side surface is reduced, and the variation in the intensity of the signal light emitted from the signal light emitting unit 14 in the arrangement direction of the light receiving elements is reduced.
[0034]
Further, in the optical data bus 50 shown in FIG. 6, when signal light is incident from the central portion of the signal light incident portion 11 (portion that is equidistant from the light absorption layers 51 and 52), it is also provided on both side surfaces. Since the light absorption layers 51 and 52 suppress the reflection of the signal light on both side surfaces, the intensity of the signal light emitted from the signal light emitting unit 14 is higher than that of the optical data bus 100 shown in FIG. The variation in the arrangement direction of the light receiving elements is reduced.
Therefore, in the optical data bus 50, when signal light is emitted from a certain light emitting element, variation in signal light received by each light receiving element is suppressed, and thus, this optical data bus 50 has different light emitting elements. Even if signal light is incident from (for example, the light emitting elements 19 and 21), variation in intensity of signal light received by a certain light receiving element due to the light emitting element is suppressed.
[0035]
In the optical data bus 50 shown in FIG. 5, the light absorption layers 51 and 52 are formed by applying an acrylic resin in which a black pigment is dispersed to the side surface of the light transmission layer 16. A black rubber may be adhered to the light absorption layer.
In the optical data bus 50 shown in FIG. 5, the light absorption layers 51 and 52 are used to suppress the reflection of the signal light on the side surface of the optical data bus 50. However, instead of the light absorption layer, the light diffusion is performed. The reflection of the signal light on the side surface of the optical data bus may be suppressed by using the layer to emit signal light from the side of the optical data bus toward the side surface of the optical data bus.
[0036]
FIG. 7 is a plan view showing an optical data bus according to the fourth embodiment of the present invention.
In the description of the optical data bus shown in FIG. 7, the same components as those constituting the optical data bus shown in FIG. 6 are denoted by the same reference numerals as those shown in FIG. Only the differences will be described.
The end surface of the optical transmission layer 65 constituting the main body of the optical data bus 60 shown in FIG. 7 on the signal light incident part 61 side is composed of an assembly of a plurality of planes 62 having different angles with respect to the signal light incident direction. Each plane 62 constituting this aggregate is formed such that its normal line intersects a point of the end face 15 of the optical data bus 60 that is equidistant from the side faces 66 and 67. The signal light incident part 61 includes a light diffusion layer 63 for diffusing the signal light incident on the signal light incident part 61. The diffusion characteristic of the light diffusion layer 63 is almost equal to the perfect diffusion characteristic. The diffusion layer 63 is bonded to each plane 62 constituting the end face of the light transmission layer 65. The normal line of the surface 64 of the light diffusion layer 63 bonded to each of the flat surfaces 62 is the same as the normal line of the end surface of the light transmission layer 65 to which the light diffusion layer 63 is bonded, to the end surface 15 of the optical data bus 60. The end surface of the optical data bus 60 on the side of the signal light incident part 61 side is incident on the signal light incident from the position near the side surfaces 66 and 67. Is composed of a set of a plurality of planes having different angles with respect to the signal light incident direction, which acts as a refracting means for refracting the light in a direction away from the one side surface.
[0037]
Further, the light absorption layers 51 and 52 that the optical data bus 60 has on both side surfaces thereof are formed by adhering black rubber to the side surface of the light transmission layer 65.
In the optical data bus 60 shown in FIG. 7, the normal line of the surface 64 of each light diffusing layer 63 intersects with a point equidistant from the side surfaces 66 and 67 of the end face 15 on the signal light emitting part 14 side. The signal light incident from the position near the one side surface (for example, the side surface 66) on the incident portion 61 side is refracted in a direction away from the side surface 66, that is, in a direction toward the central portion of the signal light emitting portion 14. The refracted signal light is diffused by the light diffusion layer 63. The diffusion characteristics of the light diffusion layer 63 are substantially equal to the perfect diffusion characteristics, and the signal light having the highest intensity among the signal lights diffused by the light diffusion layer 63 propagates toward the central portion of the signal light emitting section 14. . Further, since the optical data bus 60 has the light absorption layers 51 and 52 on both side surfaces, reflection of signal light on the side surfaces is prevented.
[0038]
As described above, the optical data bus 60 refracts the signal light incident from the position close to one side surface in a direction away from the position close to the one side surface, and diffuses the refracted signal light. Since both the means for preventing the reflection of the signal light on the side surface of the optical data bus are provided, the variation of the signal light received by each light receiving element is further reduced, depending on the position of the light emitting element. The variation in the intensity of the signal light received by the light receiving element is further suppressed.
[0039]
Like the optical data bus 60 shown in FIG. 7, the end surface on the signal light incident part 61 side is composed of an assembly of a plurality of planes having different angles with respect to the signal light incident direction, and is incident on the signal light incident part. The signal light may be refracted.
FIG. 8 is a schematic configuration diagram showing an embodiment of the signal processing apparatus of the present invention.
An optical data bus 70 is fixed to the surface of the base 71 constituting the signal processing device 80 shown in FIG. This optical data bus 70 is configured by alternately laminating an optical data bus 60 shown in FIG. 7 between clad layers 72 and a light absorbing layer 73. The signal processing device 80 includes a circuit board 77 on which the light emitting element 74, the light receiving element 75, and the electronic circuit 76 are mounted, and a base fixing part 78. The base fixing part 78 is provided on the circuit board 77. The mounted light emitting element 74 is coupled to the optical data bus 70 at the signal light incident part 61 of the optical data bus 70, and the light receiving element 75 is coupled to the optical data bus 70 at the signal light emitting part 14 of the optical data bus 70. In such a state, it is fixed on the substrate 71.
[0040]
In the signal processing device 80 configured as described above, when the electrical signal processed by the electronic circuit 76 is converted into signal light by the light emitting element 74, the signal light is diffused by the signal light incident unit 61. The light is diffused toward the optical transmission layer 65 by the layer 63, propagates through the optical transmission layer 65, and exits from the signal light emitting unit 14. The signal light emitted from the signal light emitting unit 14 is received by the light receiving element 75 and converted into an electric signal, and this electric signal is input to the electronic circuit 76 of another circuit board 77.
[0041]
Since the optical data bus 70 constituting the signal processing device 80 includes the cladding layer 72 and the light absorbing layer 73, crosstalk of signal light between adjacent optical transmission layers is suppressed.
In addition, since the signal processing device 80 includes the optical data bus 70, the intensity of the signal light emitted from the signal light emitting unit 14 of the optical data bus 70 varies depending on the incident position and the emitting position of the signal light. The design of the electronic circuit mounted on the circuit board is easy, and the S / N can be improved and the cost can be reduced.
[0042]
Further, in the signal processing device 80, each circuit board 77 is fixed to the base fixing portion 78, and at the same time, the light emitting element 74 and the light receiving element 75 mounted on the circuit board 77 are optically coupled to the optical data bus. It is configured so that delicate positioning is not necessary.
[0043]
【Example】
Examples of the present invention will be described below.
In Examples 1, 2, and 3 shown here, the optical data buses shown in FIGS. 1, 6, and 7 are used, respectively, and in the comparative example, the signal light incident portion shown in FIG. An optical data bus with a configuration was used. In the following, experimental results performed using the optical data buses of Examples 1 and 2.3 and the comparative example will be described.
[0044]
FIG. 9 is a graph showing the intensity of the signal light received by each of the light receiving elements shown in FIGS. The graph shown in FIG. 9 will be described below with reference to FIGS.
The horizontal axis of the graph represents the distance between the straight line OO ′ shown in FIGS. 1 and 2 and each light receiving element (hereinafter, FIG. 1, FIG. 2, FIG. The distance between the straight line OO ′ and each light receiving element shown in FIG. 7 is referred to as a light receiving element position, and the distance between the straight line OO ′ and each light emitting element is referred to as a light emitting element position). The vertical axis of the graph indicates the intensity of the signal light received by each light receiving element. The black triangles and black circles shown in the graph indicate the intensity of signal light received by each light receiving element when light is emitted from the light emitting elements whose light emitting element positions are 5 mm and 75 mm, respectively, in the optical data bus of Example 1. The white triangles and white circles indicate the signal light intensities received by the respective light receiving elements when light is emitted from the light emitting elements whose light emitting element positions are 5 mm and 75 mm, respectively, in the optical data bus of the comparative example. . Further, in this graph, when the light receiving element position is in the range of 15 mm to 135 mm, the white circle overlaps with the black circle.
[0045]
From the graph shown in FIG. 9, when signal light is emitted from a light emitting element whose light emitting element position is 75 mm, the intensity of the signal light received by each light receiving element is almost the same when Example 1 is compared with the comparative example. However, when signal light is emitted from a light emitting element having a light emitting element position of 5 mm, the intensity of the signal light is reduced in Example 1 as compared with the comparative example in the range of the light receiving element position of 0 mm to 120 mm. In particular, the intensity of the signal light received by the light receiving element located near the side surface 17 of the optical data bus 10 shown in FIG. 1 is greatly reduced. Accordingly, the variation in the intensity of the signal light received by each light receiving element is smaller in the first embodiment, so that when focusing on one light receiving element, this light receiving element depends on the position of the light emitting element. It can be seen that variation in the intensity of the received signal light is suppressed.
[0046]
FIG. 10 is a graph showing the intensity of the signal light received by each of the light receiving elements shown in FIGS. The graph shown in FIG. 10 will be described below with reference to FIGS.
The horizontal axis of the graph indicates the light receiving element positions of the light receiving elements arranged along the signal light emitting portion in each of the optical data buses of Example 2 and Comparative Example, and the vertical axis of the graph is received by each light receiving element. The intensity of the signal light. The black triangles and black circles shown in the graph indicate the intensity of the signal light received by each light receiving element when light is emitted from the light emitting elements whose light emitting element positions are 5 mm and 75 mm, respectively, in the optical data bus of Example 1. The white triangles and white circles indicate the signal light intensities received by the respective light receiving elements when light is emitted from the light emitting elements whose light emitting element positions are 5 mm and 75 mm, respectively, in the optical data bus of the comparative example. .
[0047]
From the graph shown in FIG. 10, when the signal light is emitted from the light emitting element whose light emitting element position is 5 mm, the intensity of the signal light in Example 2 is reduced to about half compared to the comparative example. It can be seen that the variation in the intensity of the signal light received by the light receiving element is reduced. In addition, when signal light is emitted from the light emitting element whose light emitting element position is 75 mm, the intensity of the signal light is reduced in Example 2 in the range of the light receiving element position of 15 mm to 135 mm as compared with the comparative example. In particular, the intensity of the signal light received by the light receiving elements whose light receiving element positions are 15 mm and 135 mm is greatly reduced, and the variation in the intensity of the signal light received by each light receiving element is reduced. Therefore, the variation in the intensity of the signal light received by each light receiving element is smaller in the second embodiment, so that when focusing on one light receiving element, this light receiving element depends on the position of the light emitting element. It can be seen that variation in the intensity of the received signal light is suppressed.
[0048]
FIG. 11 is a graph showing the intensity of signal light received by each of the light receiving elements shown in FIGS. The graph shown in FIG. 11 will be described below with reference to FIGS.
The horizontal axis of the graph indicates the light receiving element positions of the light receiving elements arranged along the signal light emitting part in the optical data buses of Example 3 and Comparative Example, and the vertical axis of the graph is received by each light receiving element. The intensity of the signal light. The black triangles and black circles shown in the graph indicate the intensity of the signal light received by each light receiving element when light is emitted from the light emitting elements whose light emitting element positions are 5 mm and 75 mm, respectively, in the optical data bus of Example 1. The white triangles and white circles indicate the signal light intensities received by the respective light receiving elements when light is emitted from the light emitting elements whose light emitting element positions are 5 mm and 75 mm, respectively, in the optical data bus of the comparative example. .
[0049]
From the graph shown in FIG. 11, when the signal light is emitted from the light emitting element whose light emitting element position is 75 mm, the signal light intensity in Example 3 is in the range of the light receiving element position of 15 mm to 135 mm as compared with the comparative example. In particular, the intensity of the signal light received by the light receiving elements whose light receiving element positions are in the range of 15 mm and 135 mm is greatly reduced, and the variation in the intensity of the signal light received by each light receiving element is reduced. Yes. In addition, when signal light is emitted from a light emitting element having a light emitting element position of 5 mm, the intensity of the signal light is reduced in Example 3 as compared with the comparative example when the light receiving element position is in the range of 0 mm to 120 mm. Yes. Accordingly, the variation in the intensity of the signal light received by each light receiving element is smaller in the third embodiment, and this makes it possible for the light receiving element depending on the position of the light emitting element when focusing on one light receiving element. It can be seen that variation in the intensity of the signal light received at is suppressed.
[0050]
Further, when the graph shown in FIG. 11 is compared with the graphs shown in FIGS. 9 and 10, by using the optical data bus shown in FIG. 7, the variation in the intensity of the signal light received by each light receiving element is further increased. It can be seen that is suppressed.
From the results shown in the graphs of FIGS. 9 to 11, it can be seen that a signal processing apparatus in which the S / N is improved and the cost is reduced can be obtained by using the optical data bus of the present invention.
[0051]
【The invention's effect】
As described above, according to the optical data bus of the present invention, it is highly resistant to dust and the like, is resistant to environmental changes such as temperature changes, and the circuit board can be easily attached and detached according to the expandability of the system. It is. Further, according to the optical data bus of the present invention, the change in the intensity of the emitted signal light due to the incident position and the outgoing position of the signal light can be suppressed.
[0052]
Further, according to the signal processing device of the present invention, the S / N can be improved and the cost can be reduced.
[Brief description of the drawings]
FIG. 1 is a plan view showing an optical data bus according to a first embodiment of the present invention.
FIG. 2 is a plan view showing an optical data bus in which a signal light incident portion does not include a refracting unit.
FIG. 3 is a plan view showing an optical data bus according to a second embodiment of the present invention.
4 is an operation explanatory diagram when signal light enters perpendicularly to the light diffusion layer shown in FIG. 3; FIG.
FIG. 5 is an operation explanatory diagram when signal light is incident on the light diffusion layer shown in FIG. 3 at an angle of 30 degrees.
FIG. 6 is a plan view showing an optical data bus according to a third embodiment of the present invention.
FIG. 7 is a plan view showing an optical data bus according to a fourth embodiment of the present invention.
FIG. 8 is a schematic configuration diagram showing an embodiment of a signal processing device of the present invention.
9 is a graph showing the intensity of signal light received by each of the light receiving elements shown in FIGS. 1 and 2. FIG.
10 is a graph showing the intensity of signal light received by each of the light receiving elements shown in FIGS. 2 and 6. FIG.
11 is a graph showing the intensity of signal light received by each light receiving element shown in FIGS. 2 and 7. FIG.
[Explanation of symbols]
10, 30, 50, 60, 70, 100 Optical data bus
11, 31, 41, 61 Signal light incident part
12, 33, 63 Light diffusion layer
13, 15, 35, 36 End face
14 Signal light emitting part
16, 65 Optical transmission layer
17, 18, 37, 38, 66, 67 Side
19, 20, 21, 74 Light emitting element
22, 23, 24, 75 Light receiving element
25, 26, 27, 28, 39, 40, 41, 42 Signal light
32 Signal light refraction part
51, 52 Light absorption layer
62 plane
64 surface
71 substrate
72 Clad layer
73 Light Absorption Layer
76 electronic circuit
77 Circuit board
78 Base fixing part

Claims (7)

A signal light incident part responsible for the incidence of signal light along one edge, and a signal light emission part responsible for the emission of signal light along the edge opposite to the one edge, A sheet-like optical data bus that propagates the signal light incident from the signal light incident part and emits the signal light from the signal light emission part,
Refraction that causes the signal light incident portion to refract the signal light incident from a position near one side surface of the one edge in a direction away from the one side surface, because the one edge has a curvature. An optical data bus comprising: means; and diffusing means for diffusing the refracted signal light into the optical data bus. A signal light incident part responsible for the incidence of signal light along one edge, and a signal light emission part responsible for the emission of signal light along the edge opposite to the one edge, A sheet-like optical data bus that propagates the signal light incident from the signal light incident part and emits the signal light from the signal light emission part,
The signal light incident portion is formed of an assembly of a plurality of planes whose one edge is different in angle with respect to the signal light incident direction, so that the one edge is positioned closer to one side surface. a refracting means for the incident signal light is refracted in a direction away from one side said optical data bus you characterized in that the refracted signal light, and a diffusing means for diffusing the internal optical data bus. A signal light incident part responsible for the incidence of signal light along one edge, and a signal light emission part responsible for the emission of signal light along the edge opposite to the one edge, A sheet-like optical data bus that propagates the signal light incident from the signal light incident part and emits the signal light from the signal light emission part,
A light absorber that absorbs signal light incident on the side surface of the optical data bus from the inside of the optical data bus is provided on both side surfaces of the optical data bus, and the signal light is absorbed by the light absorber, light data from the internal bus of the incident signal light to the side surface, an optical data bus you further comprising a suppressing reflection suppressing portion reflected to optical data bus inside. A signal light incident part responsible for the incidence of signal light along one edge, and a signal light emission part responsible for the emission of signal light along the edge opposite to the one edge, A sheet-like optical data bus that propagates the signal light incident from the signal light incident part and emits the signal light from the signal light emission part,
By diffusing the signal light incident on the side surface of the optical data bus from the inside of the optical data bus to both sides of the optical data bus and emitting a part of the signal light to the outside of the optical data bus, An optical data bus, comprising: a reflection suppressing unit that suppresses reflection of signal light incident on the side surface from the inside of the optical data bus into the optical data bus. Substrate,
A signal light emitting end for emitting signal light, a circuit for generating a signal to be carried on the signal light emitted from the signal light emitting end, a signal light incident end for receiving signal light, and a signal incident from the signal light incident end A plurality of circuit boards on which at least one of a circuit that performs signal processing based on a signal carried by light is mounted;
A signal light incident part responsible for the incidence of signal light along one edge, and a signal light emission part responsible for the emission of signal light along the edge opposite to the one edge, A sheet-like optical data bus that propagates signal light incident from a signal light incident part and emits the signal light from the signal light output part, wherein the signal light incident part is close to one side surface of the one end edge. An optical data bus comprising a refracting means for refracting the signal light incident from a predetermined position in a direction away from the one side surface, and a diffusing means for diffusing the refracted signal light into the optical data bus; and
  Fixing the circuit board on the substrate in a state where a signal light emitting end or signal light incident end mounted on the circuit board is coupled to the optical data bus at the signal light incident part or signal light emitting part; A signal processing apparatus comprising a plurality of substrate fixing portions. Substrate,
A signal light emitting end for emitting signal light and a signal light emitted from the signal light emitting end are carried on the signal light. A plurality of circuits on which at least one of a circuit that generates a signal and a circuit that performs signal processing based on a signal carried by the signal light incident from the signal light incident end and the signal light incident end that receives the signal light is mounted Circuit board,
A signal light incident part responsible for the incidence of signal light along one edge, and a signal light emission part responsible for the emission of signal light along the edge opposite to the one edge, A sheet-like optical data bus that propagates the signal light incident from the signal light incident part and emits the signal light from the signal light emission part. The optical data bus is formed on both sides of the optical data bus from the inside of the optical data bus. A light absorber that absorbs signal light incident on a side surface of the bus, and the optical data of the signal light incident on the side surface from the inside of the optical data bus by absorbing the signal light by the light absorber; An optical data bus having a reflection suppressing portion for suppressing reflection into the bus, and
Fixing the circuit board on the substrate in a state where a signal light emitting end or signal light incident end mounted on the circuit board is coupled to the optical data bus at the signal light incident part or signal light emitting part; A signal processing apparatus comprising a plurality of substrate fixing portions. Substrate,
A signal light emitting end for emitting signal light, a circuit for generating a signal to be carried on the signal light emitted from the signal light emitting end, a signal light incident end for receiving signal light, and a signal incident from the signal light incident end A plurality of circuit boards on which at least one of a circuit for performing signal processing based on a signal carried by light is mounted;
A signal light incident part responsible for the incidence of signal light along one edge, and a signal light emission part responsible for the emission of signal light along the edge opposite to the one edge, A sheet-like optical data bus that propagates the signal light incident from the signal light incident part and emits the signal light from the signal light emission part. The optical data bus is formed on both sides of the optical data bus from the inside of the optical data bus. The optical data bus of the signal light incident on the side surface from the inside of the optical data bus by diffusing the signal light incident on the side surface of the bus and emitting a part of the signal light to the outside of the optical data bus An optical data bus having a reflection suppressing portion for suppressing reflection to the inside, and
Fixing the circuit board on the substrate in a state where a signal light emitting end or signal light incident end mounted on the circuit board is coupled to the optical data bus at the signal light incident part or signal light emitting part; A signal processing apparatus comprising a plurality of substrate fixing portions .

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