JP3695055B2 - Optical data bus, optical data bus device, and signal processing device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sheet-like optical data bus that carries propagation of an optical signal, and a signal processing device that performs signal processing including data transmission and reception 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]
As a means to solve these problems, a light diffusion unit that diffuses the incident signal light is provided in the sheet-like optical data bus, and the signal light diffused by the light diffusion unit is propagated in all directions within the optical transmission layer. An optical data bus system can be considered. Next, an example of such an optical data bus will be described.
FIG. 12 is a cross-sectional view (a) and a plan view (b) showing how signal light is diffused when a light diffusing portion is provided in a sheet-like optical data bus.
[0007]
As shown in FIG. 12A and FIG. 12B, the signal light 95 incident on the optical data bus 90 from the direction intersecting the surface 93a of the optical transmission layer 93 is transmitted through the optical transmission layer 93. A light diffusion portion 92 is provided on the back surface 93b of the reaching light transmission layer. The signal light 95 that has reached the light diffusion portion 92 is diffused by the light diffusion portion 92 at a wide angle. In this optical data bus, it is necessary to perform alignment with the circuit board so that the signal light 95 emitted from the light emitting element of the circuit board to be connected reaches the light diffusing unit 92, as shown in FIG. As described above, by setting the area of the light diffusion portion 92 to a certain size, alignment can be easily performed. Further, since the signal light 95b is diffused at a wide angle by the light diffusing portion 92 and spreads over the entire edge 94a on the signal light emitting portion 94 side, the light receiving elements of a plurality of circuit boards are arranged to face each other along the edge 94a. Thus, the optical data bus 90 can be optically connected to a plurality of circuit boards.
[0008]
As described above, the optical data bus can be easily aligned with the circuit board of the connection partner, and the optical data bus can be optically connected to a plurality of circuit boards. The substrate can be freely replaced with each other, and it is possible to construct a highly flexible system that is rich in expandability. In addition, this optical data bus has an advantage that the signal light does not propagate in the space but propagates in the optical transmission layer and thus is not affected by environmental conditions such as dust. Furthermore, since it does not require strictness in optical alignment with the circuit board of the connection partner, it has an advantage of being resistant to temperature changes and the like.
[0009]
However, in this optical data bus, since the signal light is diffused in an average direction in all directions, the signal light 95a that does not satisfy the total reflection condition shown by the broken line in FIG. Jumps out of the light transmission layer 93 to the outside. If it is assumed that the surface is a perfect diffusion surface when the critical condition of total reflection is 45 degrees, the loss of signal light is ½, but if it is not a perfect diffusion surface, the loss of light is ½. Over. Moreover, as shown in FIG. 12B, only the signal light 95b diffused in the hatched fan-shaped direction out of the signal light diffused by the light diffusing section 92 reaches the signal light emitting section 94, and the others Since the signal light 95c diffused in the direction is wasted, the utilization efficiency of the signal light is further reduced to a fraction. For this reason, the intensity of the signal light reaching the signal light emitting section 94 of the optical data bus is weakened, and there is a problem in increasing the speed and reducing the power consumption of the signal processing device. Further, although the signal light is diffused over the entire edge 94a of the optical data bus on the side of the signal light emitting section 94, there is a variation in the amount of signal light in the width W direction of the optical data bus at the edge 4a. There is a problem in that the amount of light received between the plurality of light receiving elements on the circuit board side of the connection partner disposed opposite to the edge 94a on the signal light emitting portion 94 side of the bus varies.
[0010]
In view of the above circumstances, the present invention provides an optical data bus with high signal light transmission efficiency and little variation in the amount of emitted light at the edge on the signal light emitting portion side, and a signal processing device using the optical data bus. For the purpose.
[0011]
[Means for Solving the Problems]
The optical data bus of the present invention that achieves the above object includes a signal light incident portion that is responsible for incidence of signal light along one edge, and a signal light incident along an edge opposite to the one edge. A signal light emitting unit responsible for emission, a sheet-like optical data bus that propagates the signal light incident from the signal light incident unit and emits the signal light from the signal light emitting unit,
The one end edge has diffusion means in which a plurality of cylindrical surfaces are arranged to diffuse incident signal light into the optical data bus.
[0012]
In addition, the signal processing device of the present invention that achieves the above object includes a 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 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 diffuses the incident signal light into the one end edge inside the optical data bus An optical data bus having diffusion means in which a plurality of cylindrical surfaces are arranged, 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 in the signal light incident part or signal light emitting part; And a plurality of substrate fixing portions.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described.
FIG. 1 is a perspective view (a) and a plan view (b) showing a first embodiment of an optical data bus of the present invention.
1 (a) and 1 (b), a signal light incident part 11 responsible for the incidence of the signal light 15 and a signal light emission part 14 responsible for the emission of the signal light 16 diffused in the optical data bus 10 are shown. A sheet-like optical data bus 10 that propagates the signal light 15 incident from the signal light incident part 11 and emits it from the signal light emission part 14 is shown.
[0014]
The optical data bus 10 has diffusing means 19 in which a plurality of cylindrical surfaces 12 having a convex lens section are arranged on the edge 11a on the signal light incident portion 11 side. The diffusion means 19 has a function of diffusing the incident signal light 15 into the optical transmission layer 13 of the optical data bus 10 body.
The main body of the optical data bus 10 is a sheet-like optical transmission layer 13 having a thickness of 0.5 mm made of PMMA (polymethyl methacrylate) having a high light transmittance. The optical transmission layer 13 is manufactured by preparing a mold in advance, heating the mold to a temperature at which PMMA melts, and pouring the molten PMMA into the mold. The cylindrical surface 12 only needs to be formed only at a site where the signal light 15 is actually incident, and is not necessarily formed on the entire surface of the edge 11a.
[0015]
The cylindrical surface 12 has a function of diffusing incident incident light 15 into the light transmission layer 13, and the same PMMA as that of the light transmission layer 13 is used as the material thereof. Similar to the optical transmission layer 13, the cylindrical surface 12 is prepared by preparing a mold in advance, heating the mold to a temperature at which the PMMA melts, and pouring the molten PMMA into the mold. . In the present embodiment, the cylindrical surface 12 is illustrated as a separate member from the optical transmission layer 13 that is the main body of the optical data bus 10. After the transmission layer 13 is once formed separately, it may be used in combination as the optical data bus 10, or both may be integrated from the beginning as shown in third and fourth embodiments to be described later. It may be formed as a member.
[0016]
2A is a plan view of the optical data bus shown in FIG. 1, and FIG.
The arrangement pitch p of the cylindrical surfaces 12 in this embodiment is several hundred μm, and the arrangement pitch p is set smaller than the beam diameter of the incident light 15 emitted from the semiconductor laser and collimated by the lens. The cylindrical surface 12 in the first embodiment is formed as a convex lens, and diffuses the incident signal light 15 toward the edge 14a on the signal light emitting unit 14 side. The spread of the diffused signal light 16 varies depending on the focal length f of the cylindrical lens. In order for the diffused signal light 16 to have a sufficient broadcast property (how the signal light 16 spreads), the incident signal light 15 reaches the edge 14a on the signal light emitting part 14 side in a spread state. Thus, it is necessary to diffuse the signal light 16.
[0017]
Here, the arrangement pitch of the cylindrical surfaces 12 is p, the length of the light transmission layer 13 in the signal light transmission direction is L, the width of the edge 14a on the signal light emitting part 14 side is W, and the focal length as a cylindrical lens is f. When
f <p · L / W
By setting each parameter so as to satisfy this relationship, the spread signal light 16 can have sufficient broadcast properties.
[0018]
The signal light 15 incident on the optical data bus 10 is not diffused in the thickness direction of the sheet surface 10 a by the cylindrical surface 12, so that the signal surface 16 of the signal light 16 that diffuses in the light transmission layer 13 The spread in the thickness direction (the spread of the angle θ in FIG. 2B) is due to the original spread of the signal light 15 incident on the optical data bus 10, and all the signal light incident on the optical data bus 10 is Since the reflection condition is satisfied, the sheet surface 10a does not slip out, and is transmitted through the light transmission layer 13 and reaches the edge 14a on the signal light emitting unit 14 side.
[0019]
As described above, in the optical data bus 10 (see FIG. 2A) of the present embodiment, the incident signal light 15 is diffused only toward the signal light emitting unit 14, and as shown in FIG. There is almost no loss due to the signal light 95a that goes out of the optical transmission layer, and there is almost no loss due to the signal light 95c that spreads out of the fan shape as shown in FIG. Double signal light utilization efficiency can be obtained.
[0020]
Next, the variation in the width W direction of the edge 14a of the intensity of the signal light that has reached the edge 14a on the signal light emitting unit 14 side of the optical data bus 10 of the present embodiment will be described.
FIG. 3 is a diagram for explaining variations in signal light intensity in the signal light emitting portion of the optical data bus shown in FIG.
FIG. 3A shows the width of the edge 11a on the signal light incident part 11 side of the incident light incident on the cylindrical surface 12 formed on the edge 11a on the signal light incident part 11 (see FIG. 2A) side. FIG. 3B is a graph showing the light amount distribution according to the position in the direction, and FIG. 3B shows the width direction of the edge 14a of each signal light reaching the edge 14a on the signal light emitting portion 14 (see FIG. 2A) side. FIG. 3C is a graph showing the light quantity distribution according to the position in the width direction of the edge 14a of the signal light emitted to the outside from the edge 14a on the signal light emitting part 14 side. It is.
[0021]
As shown in FIG. 3A, the light amount distribution of the signal light 15 incident on the edge 11a on the signal light incident portion 11 side shows a Gaussian distribution shape. In the present embodiment, as described above, the arrangement pitch p of the cylindrical surfaces 12 is formed smaller than the beam diameter of the incident light 15, and the distribution curve shown in FIG. As shown, it can be divided into three regions A, B, and C. When the signal light 15 having such a light quantity distribution across the three regions A, B, and C is incident on the signal light incident portion 11 of the optical data bus 10, the signal light 15 is shown in FIG. As shown, the incident light is divided into three cylindrical surfaces 12a, 12b, and 12c. Among them, the signal light 15 incident on the cylindrical surface 12a is diffused on the cylindrical surface 12a (16a), passes through the optical transmission layer 13, and reaches the edge 14a on the signal light emitting portion 14 side. The light quantity distribution at the edge 14a of the diffused signal light 16a shows a downward-sloping distribution as shown by a curve 17a in FIG. The signal light incident on the cylindrical surface 12b is diffused on the cylindrical surface 12a (16b), passes through the optical transmission layer 13, and reaches the edge 14a on the signal light emitting portion 14 side. The light amount distribution at the edge 14a of the diffused signal light 16b shows a substantially bilaterally symmetric distribution convex upward as shown by a curve 17b in FIG. The signal light incident on the cylindrical surface 12c is diffused on the cylindrical surface 12a (16c), passes through the optical transmission layer 13, and reaches the edge 14a on the signal light emitting unit 14 side. The light amount distribution at the edge 14a of the diffused signal light 16c shows a distribution that rises to the right as shown by a curve 17c in FIG.
[0022]
On the edge 14a on the signal light emitting part 14 side, the signal lights 16a, 16b, 16c having the distributions indicated by the above three curves 17a, 17b, 17c are synthesized, and as a result, the signal obtained on the edge 14a. The light quantity distribution of light shows a substantially flat curve 18 as shown in FIG. As described above, when signal light is incident on a plurality of cylindrical surfaces at the same time, the light amount distribution at the signal light emitting portion is a substantially flat curve, but even when signal light is incident on one cylindrical surface, optical data is obtained. It is possible to function as a bus.
[0023]
The cylindrical surface 12 is not limited to a cylindrical lens having a convex lens-like cross section as in the present embodiment, but may be a cylindrical lens having a concave lens-like cross section as described below. Hereinafter, a modified example in the case where the cross section is a cylindrical lens having a concave lens shape will be described.
FIG. 4 is a perspective view (a) and a plan view (b) showing a modification of the first embodiment of the optical data bus of the present invention.
[0024]
4 (a) and 4 (b), the signal light incident part 21 responsible for the incidence of the signal light 25 and the signal light emission part 24 responsible for the emission of the signal light 26 diffusing in the optical data bus 20 are shown. A sheet-like optical data bus 20 that propagates the signal light 25 incident from the signal light incident part 21 and emits it from the signal light emission part 24 is shown.
The optical data bus 20 has a diffusing unit 29 in which a plurality of cylindrical surfaces 22 having a concave lens section are arranged on the edge 21a on the signal light incident portion 21 side. The diffusing unit 29 has a function of diffusing the incident signal light 25 into the optical transmission layer 23 of the optical data bus 20 body.
[0025]
As described above, also in the optical data bus 20 in which the plurality of concave lens-shaped cylindrical surfaces 22 are formed, the signal light emitting unit 24 is the same as in the optical data bus 10 of the first embodiment described with reference to FIG. From the side edge 24a, signal light having a substantially flat light amount distribution is emitted.
In the first embodiment described above and the modification thereof, an optical data bus having only one layer is shown, but actually, a plurality of such optical data buses are stacked to form a laminated structure. Is used as a data bus of the signal processing device. The laminated structure will be described later.
[0026]
Next, a second embodiment of the optical data bus of the present invention will be described.
FIG. 5 is a perspective view (a) and a plan view (b) showing a second embodiment of the optical data bus of the present invention.
5A and 5B, a signal light incident part 31 responsible for the incidence of the signal light 35 and a signal light emission part 34 responsible for the emission of the signal light 36 that diffuses in the optical data bus 30 are shown. A sheet-like optical data bus 30 that propagates the signal light 35 incident from the signal light incident part 31 and emits it from the signal light emission part 34 is shown.
[0027]
The optical data bus 30 has diffusing means 39 in which a plurality of cylindrical surfaces 32 having a convex lens shape in section are arranged at the edge 31a on the signal light incident portion 31 side. The diffusion means 39 has a function of diffusing the incident signal light 35 into the optical transmission layer 33 of the optical data bus 30 body.
Thus, in this embodiment, the cylindrical surface 32 is formed integrally with the optical transmission layer 33 of the main body portion of the optical data bus 30, and this point separates the cylindrical surface portion and the optical transmission layer portion. This is different from the optical data bus of the first embodiment which is combined as a unit after being formed into a single unit. Therefore, this embodiment has an advantage that the alignment between the cylindrical surface portion and the optical transmission layer portion is not necessary. All other points are the same as in the first embodiment, and as described with reference to FIG. 3, a signal having a substantially flat light amount distribution from the edge 34 a on the signal light emitting part 34 side. Light is emitted.
[0028]
The cylindrical surface 32 is not limited to a cylindrical lens having a convex lens-like cross section as in the present embodiment, but may be a cylindrical lens having a concave lens-like cross section as shown below. . Hereinafter, a modified example in the case where the cross section is a cylindrical lens having a concave lens shape will be described.
FIG. 6 is a perspective view (a) and a plan view (b) showing a modification of the second embodiment of the optical data bus of the present invention.
[0029]
6 (a) and 6 (b), a signal light incident part 41 responsible for the incidence of the signal light 45 and a signal light emission part 44 responsible for the emission of the signal light 46 diffused in the optical data bus 40 are provided. A sheet-like optical data bus 40 that propagates the signal light 45 incident from the signal light incident part 41 and emits the signal light from the signal light output part 44 is shown.
The optical data bus 40 has diffusing means 49 in which a plurality of cylindrical surfaces 42 having a concave lens section are arranged on the edge 41a on the signal light incident portion 41 side. The diffusion means 49 has a function of diffusing the incident signal light 45 into the optical transmission layer 43 of the optical data bus 40 main body.
[0030]
As described above, also in the optical data bus 40 in which the plurality of cylindrical surfaces 42 are formed, as in the optical data bus 30 of the second embodiment described with reference to FIG. Signal light having a substantially flat light amount distribution is emitted from the edge 44a.
In the above-described second embodiment and its modification, an optical data bus having only one layer is shown, but actually, a plurality of such optical data buses are stacked to form a laminated structure. Is used as a data bus of the signal processing device.
[0031]
Next, a third embodiment of the optical data bus of the present invention will be described.
FIG. 7 is a perspective view (a), a plan view (b), and a sectional view (c) showing an outline of the third embodiment of the optical data bus of the present invention.
7A, 7 </ b> B, and 7 </ b> C, the signal light incident unit 51 that is responsible for the incidence of the signal light 55 and the signal that is responsible for the emission of the signal light 56 that is diffused in the optical data bus 50. A sheet-like optical data bus 50 that has a light emitting part 54, propagates the signal light 55 incident from the signal light incident part 51 and emits it from the signal light emitting part 54 is shown.
[0032]
An edge 51a of the optical data bus 50 on the side of the signal light incident portion 51 is formed obliquely with respect to the sheet surface 50a of the optical data bus 50, and a plurality of cylindrical surfaces 52 having a convex lens shape in section are arranged on the oblique end surface. The diffusion means 59 is provided. By this diffusing means 59, the signal light 55 incident from the direction intersecting the sheet surface 50a of the optical data bus 50 is reflected by the inclined cylindrical surface 52 in the direction toward the signal light emitting portion 54 and at the same time, the optical data bus 50 main body. It diffuses into the optical transmission layer 53.
[0033]
In the present embodiment, the signal loss on the cylindrical surface can be extremely reduced by making the inclination angle of the cylindrical surface 52 with respect to the sheet surface 50a larger than the angle satisfying the total reflection condition. Even if the total reflection condition is not satisfied by forming a reflective film such as aluminum on the surface of the cylindrical surface 52 by vapor deposition, it is possible to further improve the transmission efficiency of the signal light. Although the angle can be set to an arbitrary angle, it is usually desirable to set the inclination angle to 45 degrees.
[0034]
The optical data bus of the present embodiment is configured such that an edge 51a formed obliquely with respect to the sheet surface 50a reflects incident light 55 in the direction of the signal light emitting portion 54, and is connected to the circuit board side to be connected. Since the projection surface onto the sheet surface of the signal light incident portion 51 viewed from above has a certain spread, the signal light from the light emitting element of the circuit board is connected when this optical data bus is connected to the circuit board. The optical alignment can be performed very easily by simply aligning the optical axes so that the optical axis falls within the wide projection plane.
[0035]
Also in the present embodiment, the signal light 55 incident on the optical data bus 50 is not diffused in the thickness direction of the sheet surface 50 a by the cylindrical surface 52, so that the signal diffused in the optical transmission layer 53 The spread of the light 56 in the thickness direction of the sheet surface 50a is due to the original spread of the signal light 15 incident on the optical data bus 50, and the signal light incident on the optical data bus 50 satisfies the total reflection condition. The light does not slip out of the sheet surface 50a, and is transmitted through the light transmission layer 53 to reach the edge 54a on the signal light emitting portion 54 side.
[0036]
In the third embodiment described above, an optical data bus having only one layer is shown. Actually, however, a signal processing apparatus has a laminated structure in which a plurality of such optical data buses are stacked. Used as a data bus.
Next, a fourth embodiment of the optical data bus of the present invention will be described.
FIG. 8 is a plan view (a) and a partially enlarged view (b) showing an outline of the fourth embodiment of the optical data bus of the present invention.
[0037]
The basic configuration of this embodiment is the same as that of the second embodiment. As shown in FIG. 8 (a), this optical data bus 60 receives signal light that bears the incidence of signal light 65a, 65b, 65c. Unit 61 and a signal light emitting unit 64 for emitting signal light 66a, 66b, 66c that diffuses in the optical data bus 60, and propagates the signal light 65 incident from the signal light incident unit 61 and transmits the signal light This is a sheet-like optical data bus that exits from the exit section 64.
[0038]
Diffusing means 69 is formed by forming cylindrical surfaces 62a, 62b, and 62c at three signal light incident positions A, B, and C of the edge 61a on the signal light incident portion 61 side of the optical data bus 60. ing. The diffusing unit 69 has a function of diffusing the incident signal light 65 into the optical transmission layer 63 of the optical data bus 60 main body.
The cylindrical surface 62b formed at the center position (signal light incident position B) of the optical data bus 60 at the edge 61a on the signal light incident portion 61 side is the same as the cylindrical surface shown in the first to third embodiments. Similarly, it is formed in a symmetrical cylindrical lens shape, and the focal length and the arrangement pitch are set so that the signal light is diffused over the entire edge of the signal light emitting portion 64.
[0039]
On the other hand, the cylindrical surface 62a formed at the position (signal light incident position A) of the edge 61a on the side of the signal light incident portion 61 near the one side surface 67a of the optical data bus 60 causes the incident signal light to pass through the side surface 67a. It is formed in such a shape that it is more diffused to the other side surface 67b side opposite to this side, that is, as shown in FIG. 8B, a part of the arc of the convex lens is cut out. Also, the cylindrical surface 62c formed at the position (signal light incident position C) of the end edge 61a near the other side surface 67b opposite to the one side surface 67a of the optical data bus 60 is the same as the cylindrical surface 62a. It is formed in a shape in which a part of the arc of the convex lens is cut out.
[0040]
The cylindrical surface 62a and the cylindrical surface 62c have such special shapes, and the signal light is diffused by setting the focal length and the arrangement pitch so that the signal light is diffused over the entire edge 64a of the signal light emitting section 64. By controlling the direction, all the signal lights 66a, 66b, 66c are diffused over the entire edge 64a.
Next, a description will be given of a configuration in the case where a laminated structure in which a plurality of optical data buses shown in the first to fourth embodiments are stacked is used as a data bus of a signal processing device.
[0041]
FIG. 9 is a schematic diagram of an optical data bus having a stacked structure in which a plurality of light transmission layers, a cladding layer, and a light absorption layer are stacked.
As shown in FIG. 9, a laminate comprising the optical transmission layer 2 and the two clad layers 3 sandwiching the optical transmission layer 2 from both sides forms a transmission path for transmitting signal light. Further, a plurality of layers are stacked with the light absorption layer 4 interposed therebetween to form an optical data bus 1 having a stacked structure. In this way, the optical data bus 1 has a laminated structure composed of a plurality of optical transmission layers 2, so that signal light from an arbitrary number of signal processing circuits can be transmitted from a plurality of bits via the optical data bus 1 of this laminated structure. As a parallel optical signal, it can be transmitted to or received by any number of signal processing circuits.
[0042]
Note that the optical data bus of the present invention is not intended only for one formed as a laminated structure, but also includes an optical data bus provided with only one optical transmission layer. When there is only one optical transmission layer, for example, a plurality of signal lights can be simultaneously transmitted and received by distinguishing the plurality of signal lights from each other by the wavelength of the signal light.
Next, an embodiment of the signal processing apparatus of the present invention will be described.
[0043]
FIG. 10 is a schematic configuration diagram of an embodiment of a signal processing device of the present invention. In this signal processing apparatus, a plurality of optical data buses having the same shape as the optical data bus 50 described with reference to FIG. 7 and having a plurality of diffusing means in which a plurality of cylindrical surfaces are arranged on oblique end surfaces are used. It has been.
As shown in FIG. 10, a signal light emitting end 82 that emits signal light toward the optical data bus 50 and a signal light emitting end 82 are emitted on a mother board 70 that is an example of a substrate according to the present invention. A circuit 81 such as a VLSI that generates a signal to be carried by the signal light, a signal light incident end 84 for receiving the signal light emitted from the optical data bus 50, and a signal carried by the signal light incident from the signal light incident end 84 A plurality of circuit boards 80 mounted with a circuit 81 such as a VLSI that performs signal processing based on the above are mounted.
[0044]
In the plurality of circuit boards 80, the signal light emitting end 82 to the signal light incident end 84 mounted on each circuit board 80 have an optical data bus in the signal light incident part 51 (see FIG. 7) to the signal light emitting part 54. 50 is fixed to the mother board 70 by a plurality of board fixing parts 71 fixed on the mother board 70 in a state of being coupled to the mother board 70.
FIG. 11 is a schematic diagram showing an optical connection state between the signal light incident / exit section of the optical data bus and the signal light incident / exit end of the circuit board.
[0045]
As shown in FIG. 11, the signal light emitting end 82 of the circuit board 80 is provided with a plurality of light emitting elements 83, and the signal light incident end 84 is provided with a plurality of light receiving elements 85, respectively. 71 (see FIG. 10), the light emitting element 83 is arranged at a position corresponding to the signal light incident portion 51 of each optical transmission layer 53 of the optical data bus 50, and the light receiving element 85 is each of the optical data bus 50. The light transmission layer 53 is disposed at a position corresponding to the signal light emitting portion 54. The signal light incident portion 51 of each optical transmission layer 53 of the optical data bus 50 is provided with the diffusing means 59 having a plurality of cylindrical surfaces 52 arranged as described with reference to FIG. 59 diffuses the incident signal light into each optical transmission layer 53. Thus, each circuit board 80 and each optical transmission layer 53 of the optical data bus 50 are optically coupled.
[0046]
Returning to FIG. Electrical wiring (not shown) is provided on the motherboard 70, and these electrical wirings are circuits such as VLSI on the circuit board 80 mounted on the board fixing part 71 via the board fixing part 71. 81 is electrically connected. By attaching the circuit board 80 to the board fixing portion 71, the light emitting element 83 provided at the signal light emitting end 82 of the circuit board 80 performs electrical / optical conversion of the electrical signal processed and output by the circuit 81, The converted signal light is emitted toward the signal light incident portion 51 of the optical data bus 50.
[0047]
The signal light incident on the signal light incident part 51 of the optical data bus 50 is diffused in each optical transmission layer 53 and propagates to the signal light emitting part 54, and the signal light incident end 84 of the circuit board 80 is transmitted from the signal light emitting part 54. The light is emitted to the light receiving element 85 included in the. The signal light received by the light receiving element 85 is photoelectrically / electrically converted, and the converted electric signal is input to another electronic circuit 81 for processing.
[0048]
Next, optical alignment between the optical data bus 50 and the circuit board 80 will be described. In this optical data bus 50, as shown in FIG. 11, a cylindrical surface 52 (reflecting incident signal light in the direction of the signal light emitting portion 54 is formed on the oblique end surface of the edge 51a on the signal light incident portion 51 side. 7) are arranged, the circuit can be obtained simply by aligning the signal light emitting part 54 on the optical data bus 50 side and the light receiving element 85 provided on the signal light incident end 84 on the circuit board 80 side. Optical alignment between the light emitting element 83 provided at the signal light emitting end 82 of the substrate 80 and the signal light incident portion 51 of the optical data bus 50 is automatically performed. Therefore, it is possible to freely insert and remove both the optical data bus 50 and the circuit board 80, and it is possible to configure a highly flexible signal processing apparatus that is rich in expandability. In addition, as described with reference to FIG. 7, this signal processing device uses an optical data bus that performs diffusion with high transmission efficiency by a cylindrical lens with little signal light loss. A power signal processing apparatus can be obtained.
[0049]
In this embodiment, a signal light emitting end that emits signal light, a circuit that generates a signal to be carried by the signal light emitted from the signal light emitting end, a signal light incident end that receives the signal light, and the circuit Although only a circuit board on which both circuits for performing signal processing based on a signal carried by signal light incident from the signal light incident end are mounted is shown, the circuit board is not necessarily limited to the one having the above-described configuration. Rather than a signal light emitting end that emits signal light, a circuit that generates a signal to be carried on the signal light emitted from the signal light emitting end, a signal light incident end that receives the signal light, and a signal light incident end A circuit board on which only one of the circuits that perform signal processing based on the signal carried by the incident signal light may be mounted.
[0050]
【The invention's effect】
As described above, according to the optical data bus of the present invention, the signal light incident on the optical data bus is diffused over the entire edge of the signal light emitting part side by the diffusion means in which a plurality of cylindrical surfaces are arranged. Therefore, the optical data bus that can minimize the signal light that goes out of the optical transmission layer out of the signal light, has high transmission efficiency, and has little variation in the amount of emitted light at the edge on the signal light emitting part side. Can be obtained.
[0051]
Also, according to the signal processing apparatus of the present invention, by using the optical data bus of the present invention, transmission / reception with high signal light transmission efficiency and small variation in signal light intensity among a plurality of substrates is possible. Therefore, a high-speed and low power consumption signal processing device can be realized. In addition, since both the optical data bus and the circuit board can be freely inserted and removed, a highly flexible signal processing apparatus with high expandability can be configured.
[Brief description of the drawings]
FIG. 1 is a perspective view (a) and a plan view (b) showing a first embodiment of an optical data bus of the present invention.
2A is a plan view of the optical data bus shown in FIG. 1 and FIG.
3 is a diagram for explaining variation in signal light intensity in a signal light emitting part of the optical data bus shown in FIG. 2; FIG.
FIGS. 4A and 4B are a perspective view and a plan view showing a modification of the first embodiment of the optical data bus of the present invention. FIGS.
FIGS. 5A and 5B are a perspective view and a plan view showing a second embodiment of the optical data bus of the present invention. FIGS.
6A and 6B are a perspective view and a plan view showing a modification of the second embodiment of the optical data bus of the present invention.
FIG. 7 is a perspective view (a), a plan view (b), and a sectional view (c) showing an outline of a third embodiment of the optical data bus of the present invention.
FIGS. 8A and 8B are a plan view and a partially enlarged view showing an outline of a fourth embodiment of the optical data bus of the present invention. FIGS.
FIG. 9 is a schematic diagram of an optical data bus having a stacked structure in which a plurality of light transmission layers, a cladding layer, and a light absorption layer are stacked.
FIG. 10 is a schematic configuration diagram of an embodiment of a signal processing device of the present invention.
FIG. 11 is a schematic diagram showing an optical connection state between a signal light incident / exit part of an optical data bus and a signal light incident / exit end of a circuit board.
FIGS. 12A and 12B are a cross-sectional view and a plan view showing a state of signal light diffusion when a light diffusing portion is provided in a sheet-like optical data bus. FIGS.
[Explanation of symbols]
1 Optical data bus
2 Optical transmission layer
3 Clad layer
4 Light absorption layer
10, 20, 30, 40, 50, 60 Optical data bus
10a, 50a Sheet surface
11, 21, 31, 41, 51, 61 Signal light incident part
11a, 14a, 21a, 31a, 41a, 51a, 61a
12, 12a, 12b, 12c, 22, 32, 42, 52, 62a, 62b, 62c Cylindrical surface
13, 23, 33, 43, 53, 63 Optical transmission layer
14, 24, 34, 44, 54, 64 Signal light emitting part
15, 16, 16a, 16b, 25, 26, 35, 36, 45, 46, 55, 56, 65, 66, 66a, 66b, 66c Signal light
17a, 17b, 17c, 18 curves
19, 29, 39, 49, 59, 69 Diffusion means
70 Motherboard
71 Board fixing part
80 circuit board
81 circuits
82 Signal light output end
83 Light emitting device
84 Signal light incident end
85 Light receiving element
90 Optical data bus
92 Light diffusion part
93 Optical transmission layer
93a surface
93b reverse side
94 Signal light emitting part
94a edge
95, 95a, 95c Signal light

Claims (14)

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,
Diffusion in which a plurality of cylindrical surfaces are arranged in a direction in which the central axis of the cylindrical surface coincides with the thickness direction of the sheet. An optical data bus comprising means.   2. The optical data bus according to claim 1, wherein the cylindrical surface has a convex shape when viewed from the signal light incident side.   2. The optical data bus according to claim 1, wherein the cylindrical surface has a concave shape when viewed from the incident side of the signal light.   The optical data bus according to any one of claims 1 to 3, wherein a plurality of cylindrical surfaces arranged at the one end edge are integrated with an area where the signal light is transmitted.   2. The optical data bus according to claim 1, wherein an arrangement pitch of the cylindrical surfaces is configured so that the signal light is simultaneously incident on the plurality of cylindrical surfaces. The one end edge is formed obliquely with respect to the sheet surface of the optical data bus, and the cylindrical surface is formed on the oblique end surface,
The signal light incident portion is configured to diffuse the signal light from the position along the one edge of the sheet surface, reflected by the cylindrical surface, and diffused in the optical data bus. The optical data bus according to claim 1.   The cylindrical surface formed at a position near the one side surface of the optical data bus at the one end edge allows the incident signal light to be transmitted to the optical data bus from the one side surface side. 2. The optical data bus according to claim 1, wherein the optical data bus is formed in a shape that diffuses greatly to the other side surface opposite to the one side surface. 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 ,
The signal light incident part is responsible for incident signal light incident in the thickness direction of the sheet, and
A plurality of cylindrical surfaces for diffusing the incident signal light into the optical data bus at the one end edge are arranged in a direction in which the central axis of the cylindrical surface is inclined with respect to the thickness direction of the sheet. An optical data bus comprising a diffusion means. 9. The optical data bus according to claim 8, wherein a central axis of the cylindrical surface is inclined by 45 ° with respect to a thickness direction of the sheet. Signal light for incident signal light, in which a plurality of cylindrical surfaces for diffusing incident signal light are arranged on one edge in a direction in which the central axis of the cylindrical surface coincides with the thickness direction of the sheet An incident portion and a signal light emitting portion for emitting signal light along an edge opposite to the one edge, and propagates the signal light incident from the signal light incident portion to transmit the signal light A sheet-like optical data bus exiting from the light exit section;
A signal light transmitting unit that is disposed along the one edge and that enters the signal light into the signal light incident unit, and a signal light receiving unit that receives the signal light emitted from the signal light emitting unit. Optical data bus device. A plurality of the optical data buses are stacked, and each of the signal light transmitting unit and the signal light receiving unit is provided corresponding to the optical bus, and the signal light is composed of bits corresponding to the plurality of optical buses. 11. The optical data bus device according to claim 10, wherein the optical data bus device is transmitted and received as a parallel signal. A cylindrical surface for diffusing the incident signal light is arranged at one end of the cylindrical surface in a direction in which the central axis of the cylindrical surface is inclined with respect to the thickness direction of the sheet. A signal light incident part, and a signal light emission part for emitting signal light along an edge opposite to the one edge, and propagates the signal light incident from the signal light incident part A sheet-like optical data bus exiting from the signal light exit section;
A signal light transmitting unit that is disposed along the one edge and that enters the signal light into the signal light incident unit, and a signal light receiving unit that receives the signal light emitted from the signal light emitting unit. Optical data bus device. A plurality of the optical data buses are stacked, and each of the signal light transmitting unit and the signal light receiving unit is provided corresponding to the optical bus, and the signal light is composed of bits corresponding to the plurality of optical buses. 11. The optical data bus device according to claim 10, wherein the optical data bus device is transmitted and received as a parallel signal. 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 other 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 the incident signal light is transmitted to the one end edge inside the optical data bus. An optical data bus having diffusion means in which a plurality of cylindrical surfaces are arranged in a direction in which the central axis of the cylindrical surface coincides with the thickness direction of the sheet;
  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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