Integrated optical transmitter and/or receiver.

p0001The invention relates to an optical receiver and / or transmitter according to the preamble of claim 1.

p0002When using optical fibers as a transmission medium are at the beginning and end of the route transmitter or receiver modules spliced, are converted by the electrical signals into optical signals and at the end of the route back into electrical signals. For long distances between amplifier modules are provided for signal processing at certain intervals.

p0003The modules of the aforementioned type have been produced separately in discrete or hybrid technology. They are located in a housing, protrude from the fiber optic connectors and / or wire connections. Such modules are expensive and require a relatively large space. The latter is very inconvenient if other at a plurality of parallel optical waveguides, for example in the case of a cable, transmitter or receiver modules or repeater modules or are to be spliced.

p0004The object of the invention is to reduce the volume of the individual modules, and at the same time the manufacturing costs.

p0005This object is solved by the features indicated in claim 1. The sub-claims reveal advantageous embodiments of the subject invention.

p0006The advantages achieved by the invention consist in accordance with claim 1 and 2 in particular in that a plurality of similar modules to form a line or area array, preferably integrated monolithically, are summarized in a small area that the terminals all lie in a plane, and in that the optical fiber ends are aligned on blind holes to the light-sensitive or light-emitting elements of the modules, so that a separate time-consuming and costly adjustment unnecessary.

p0007With reference to two embodiments, the invention in conjunction with the drawings will be explained in more detail below. It shows:<dl id="dl0001"><dt>Fig. 1</dt><dd> a first embodiment of a line array with monolithically integrated receiver modules according to the invention in a schematic representation;</dd><dt>FIG. 2</dt><dd> the circuitry of a receiver module as in accordance with the embodiment. is used FIG. 1;</dd><dt>Fig. 3</dt><dd> is a partial view of the line array according to FIG 1 in cross section and enlarged scale. </dd><dt>Fig. 4</dt><dd> a second embodiment of a line array with monolithically integrated repeater modules according to the invention in a schematic representation;</dd><dt>Fig. 5</dt><dd> the circuit of an intermediate amplifier module, as used in the embodiment of Fig. 4;</dd><dt>Fig. 6</dt><dd> a partial view of the line array of FIG. 4 in cross-section and enlarged scale.</dd></dl>

p0008Figures 1 to 3 show a first embodiment of a line array with a plurality of monolithically integrated receiver modules. 9

p0009Fig. 1 shows a schematic representation of a line array with a substrate 4 as a carrier that exists for the above optical waveguides guided light from a transparent semiconductor material. On one surface of the substrate 4 (Fig. 3, Pos. 6) 9 is disposed a plurality monolithically integrated optical receiver modules in preferably uniform distances. On the other surface of the substrate 4 (Fig. 3, Pos. 5) are in alignment with light-sensitive elements, for example photodiodes (Fig. 3, Pos. 10), the modules 9 arranged at right angles to the substrate surface, light waveguides 2. The optical waveguide 2 are part of a short piece of cable 1. Up to electrical terminals 13 of the receiver modules 9, the line array via the array-oriented end of the piece of cable 1 is embedded to protect and strain relief in an encapsulant 15th The free end of the piece of cable 1 has fiber optic connectors 2a through which the receiver modules 9 of the line array are spliced ​​in a known manner to the optical waveguide of a transmission path.

p0010Fig. 2 shows the circuitry of a receiver module 9, by which the above light waveguide 2 supplied light signals are converted into electrical signals at the end of a transmission link. A module 9 consists essentially of a photodiode 10, a preamplifier 11 and a main amplifier 12, whose output is connected to an output terminal. 13

p0011Fig. 3 shows in enlarged scale and in a schematic representation a portion of the line array of FIG. 1 in cross-section. The substrate 4 is provided as shown with preferably uniformly spaced blind holes. 7 They extend up close to the opposite surface 6 of the substrate 4. The diameter of the blind holes 7 is selected so that the holes 7 forming a substantially play-free guidance of the liberated from the mantle ends 3 of the optical fiber 2 after deposition of an antireflection coating, not shown. The length of the ends 3 is equal to the depth of the blind holes 7. The abutting with the end face of the protective jacket to the substrate surface 5 optical waveguide 2 are fixed in the position shown by bonding 14 with the surface of the fifth On the surface of the substrate 6 4 8 pin photodiodes for example are 10 diffused in alignment of the photosensitive surfaces of the blind holes 7 in epitaxial layers. Details of such photodiodes can font "Physical music", Vol. 44 - No. 4 - APRIL 88, sides are taken 91 to 97. The photodiodes 10 associated electronic components 11 and 12 are also integrated monolithically.

p0012Figures 4 to 6 show a second embodiment of a line array with monolithically integrated repeater modules 20th

p0013Fig. 4 is - similar to the above example - a schematic representation of a line array with a substrate 24 as a carrier, which likewise for the light emerging from the optical fibers light from a transparent semiconductor material. On one side of the substrate 24 a plurality monolithically integrated electrical repeater modules 20 in preferably uniform distances is arranged. On the other side of the substrate 24 of the modules 20, optical waveguides 2 and 22 are in alignment with light-sensitive elements, for example photodiodes (Fig. 6, Pos. 10) and light-emitting elements (Fig. 6, Pos. 19) is arranged. The optical waveguides 2 and 22 belong to a transmission cable, which is divided by a splicing of the line array in an incoming cable and an outgoing cable 16 21st As in the above example, the connected line array is embedded beyond the ends of the cables 16 and 21 in a sealing compound.

p0014Fig. Figure 5 shows the circuit of an intermediate amplifier module 20 via the optical waveguide 2 incoming light signals are converted in known per se manner via a photodiode 10 into electrical signals, amplified in 11 and 12, processed in a regenerator 17 and via a driver stage 18 with a downstream laser diode 19 as a regenerated optical signal via the optical waveguide respectively connected 22 reproduced on the route.

p0015Fig. Figure 6 shows in enlarged scale and in a schematic representation a portion of the line array of FIG. 4 in cross section. As with the previous example, the substrate 24 is provided with preferably uniformly spaced blind holes 27th They are formed in the manner described above. On the surface 26 of the substrate 24 such as PIN photodiodes 27 and 10 are laser diodes 19 diffused into epitaxial layer 28 in alignment with the blind holes. The light-emitting surface of a laser diode 19 is directed in centric alignment with the associated blind hole 27 to the substrate. Such lasers are described as so-called Short Cavity LD or Surface Emitting Laser injuction known and in the conference program of the Ninth IEEE International Semiconductor Laser Conference, July 7-10, 1984, pages 52 and 53 collectively. The said signal conditioning electronic components 11, 12, 17 and 18 are also integrated monolithically and connected to one another via conductor tracks 29th

p0016While the first embodiment has the line array made up connections, the second embodiment provides a direct connection to the optical waveguide 2 and 22 respectively. To 3 and 23 facilitate the insertion of the liberated from the protective sheath optical fiber ends in the property, holes 27, a shadow mask 30 having guide holes 31 on the substrate surface 25th To facilitate insertion of the optical fibers 2 and 22, the guide holes 31 have outwardly a funnel-shaped widening 32. The shadow mask 30 is so thick that the inserted optical waveguide 2 and 22 already resulted in the hole 31 before the optical fiber end 3 and 23 in the associated blind hole 27 occurs. The staggered arrangement of the optical waveguide 2 and 22 in FIG. 6 illustrates the Predicted. Introduced to stop optical waveguide 2 and 22 are fixed by bonding 14 with the shadow mask 30th

p0017Has a cable a greater number of optical fibers, so the required number of modules 9 and 20 combined in the form of an area array.