JPS59146004A - Optical integrated circuit - Google Patents

Abstract

PURPOSE:To facilitate the coupling between an optical fiber and an integrated circuit and to improve the precision of the coupling by forming a groove for fixing the optical fiber in the surface of a substrate at the top of a waveguide which couples with the optical fiber. CONSTITUTION:The waveguide 8 consisting of a waveguide layer 6 formed on the substrate 5 and a clad layer 7 formed thereupon is cut in the middle and the groove 9 is formed from the tip surface of the waveguide 8 to the end surface of the substrate 5. The optical fiber 10 is fitted and adhered fixedly in the groove 9 and the position of the optical fiber 10 is specified by the groove 9 to set the optical fiber at a normal position in coupling with the waveguide 8. Thus, the coupling between the optical fiber and integrated circuit is facilitated and improved in precision, so a system by the coupling is stabilized.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical integrated circuit, and relates to an optical integrated circuit used in conjunction with an original fiber, such as a transmitter for optical communication, a branching element, a single branching element, a modulation element, an optical fiber gyro, and an optical integrated circuit. It is useful as an optical integrated circuit for measurements using optical fibers, such as a no-hydrofon.

A conventional optical integrated circuit is formed by integrating optical functional elements such as a laser diode (Ll), a photodiode (PD), and a switching element on a single substrate, and coupling these elements with a waveguide.

Figure 1 shows the optical integrated circuits in this building. As shown in the figure, this optical integrated circuit switches the output of J.1) to two waveguides 1 and 2 using a switching element SW, and an optical fiber 3.4 is connected to waveguide 1.2. When combined, it functions as a transmitter for "C" optical communication. At this time, the PD is an output monitor of the LD.

In the optical integrated circuit used in conjunction with the optical fiber 3.4, when the waveguides 1 and 2 and the optical fiber 3.4 are both single mode, the waveguide size and core diameter are both on the μm order. Therefore, a high degree of positioning accuracy is required to achieve optimal coupling. For this reason, in the optical integrated circuit according to the prior art, not only manufacturing difficulties but also instability as a system, for example, a drift in the outputs of the optical 7-eyepers 3 and 4 due to a drift in the amount of coupling are caused. That is, when the waveguides 1 and 2 and the optical fibers 3 and 4 of the optical integrated circuit are both single mode, positioning accuracy on the order of a submicron is required to couple them, and this coupling itself is difficult. However, it has the disadvantage that the system becomes unstable.

SUMMARY OF THE INVENTION In view of the above-mentioned prior art, it is an object of the present invention to provide an optical integrated circuit that can be easily coupled to an optical fiber and can realize a stable system. The technical concept of the present invention, which achieves this object, is based on the fact that a groove for fixing the original fiber is formed on the substrate at the tip of the waveguide to be coupled to the nine fibers.

Embodiments of the present invention will be described below in detail based on the drawings.

As shown in FIG. 2, in this embodiment, a waveguide layer 6 formed on a substrate 5 and a clad Ig!
The waveguide 8 consisting of the waveguide 7 is cut in the middle, and a groove 9 is formed from the tip end face of the waveguide 8 to the end face of the substrate 5. An optical fiber 10 can be inserted and fixed into the groove 9, and the position of the optical fiber 10 is regulated by the groove 9 so that it occupies a normal position apart from coupling with the waveguide 8. It has become.

Such a photonic product circuit is manufactured through the following steps. As shown in FIG. 3(a), an in Ga AsP waveguide layer 6 is formed by Evita kinial growth using inl' as a substrate 5.
Then, a JnP cladding layer 7 is formed. Next, Figure 3 (b
), a strip-loaded waveguide 8 is formed by quad-etching.

Finally, as shown in FIG. 3(C), a groove 9 extending from the tip surface of the waveguide 8 to the end surface of the substrate 50 is formed by photoetching 6, and an optical eyeper is attached and identified to this groove 9. In this case, if the outer diameter of the optical fiber is 125
μm, and 71. If the groove 9 for fixing the fiber is shallow, the original fiber is etched with HF (hydrogen fluoride) or the like in advance to reduce the diameter.

fx, LD, PD, switching elements, etc. can also be formed on the substrate 5, but since this aspect is the same as that shown in FIG. 1, illustration thereof is omitted.

FIG. 4 shows another embodiment of the present invention in which an optical functional section having an optical functional element and a groove for fixing an optical fiber are formed on separate substrates. As shown in the figure, the optical function section] 1-: A section having a light (sensing element) similar to that of the optical integrated circuit shown in FIG.

This optical function section 11 is fitted into a housing section 12a, which is a recess formed in the substrate 12. At this time, the substrate 12 has a groove 12b into which the optical fiber is inserted and firmly attached to the bone. Thus, by fitting the optical function part 11 into the storage part 12a and fitting and fixing the optical fiber 13 into the groove 12b, the waveguide 11a of the optical function part 11 and the optical fiber 13 are coupled with high precision.

The optical integrated circuit according to the present invention is GaAs.

lnP, Si, LiNbO3, B112Si0
2o, transmitters, receivers, repeaters, branching elements, demultiplexing elements, etc. using glass or the like as substrates.

As explained above in detail with the embodiments, according to the present invention, when coupling with the original fiber, it is sufficient to simply fix the pigtail fiber in the groove and use splicing using existing technology. Not only is the connection with the debt circuit easier, but also the system can be stabilized because this connection can be made commercially.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing a conventional bond collector circuit together with a τ-source fiber, FIG. 2 is a perspective view showing the sleeve of an optical integrated circuit according to an embodiment of the present invention, and FIG. 3<8) to Figure 3 (C)
FIG. 4 is a perspective view for explaining the manufacturing process thereof, and FIG. 4 is a perspective view showing a mounting part of an optical integrated circuit according to another embodiment of the invention. In the drawing, 5.12Vi substrate, 8+11a is a waveguide, 9.12b is a groove, 10.13 is an optical fiber, and 12a is a storage part. Patent Applicant: Sumitomo Electric Industries, Ltd. Representative Patent Attorney Mitsuishi Shibu Cai) 1st Ward, 3rd Ward, Figure 2, Figure 5/ Figure 4

Claims (2)

[Claims] (1) In an optical integrated circuit having an optical functional element such as a laser diode or an optical switch, a groove for inserting and fixing an optical fiber coupled to the waveguide is formed on the substrate extending from the tip surface of the waveguide to the end surface of the substrate. An optical integrated circuit characterized by the fact that it has been formed. (2) In an optical integrated circuit having an optical functional element such as a laser diode or an optical switch, an optical functional part formed by forming the optical functional element on a substrate, and a housing part that is a recess into which this optical functional part can be fitted. What is claimed is: 1. An optical integrated circuit comprising: a substrate having a groove for inserting and fixing an optical fiber coupled to a waveguide of a pre-ml optical function section;