JPH11234211A - Optical communication equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform optical communication for a long distance, which exceeds the transfer enable distance of a plastic fiber, in simple configuration. SOLUTION: A light emitting element 11 and a photodetector 12 are photocoupled to a first plastic fiber 10a, and a light receiving/emitting element 15 or the like is photocoupled to a second plastic fiber 10b. The first plastic fiber 10a is photocoupled through a photocoupler 13a to a quartz fiber 14, and the quartz fiber 14 is photocoupled through a photocoupler 13b to the second plastic fiber 10b. The photocouplers 13a and 13b are composed of lenses or the like for condensing the light, which is emitted and scattered from one end face of the first and second plastic fibers 10a and 10b and the quartz fiber 14, on the other end face of the first and second plastic fibers 10a and 10b and the quartz fiber 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical communication apparatus for wavelength-division multiplexing transmission between a plurality of devices such as personal computers and AV devices using an optical fiber, for example, when constructing a home network.

[0002]

2. Description of the Related Art An optical fiber used in an optical communication apparatus has a core material of quartz (hereinafter referred to as a quartz fiber) and a core material of a plastic material (hereinafter referred to as a plastic fiber). ) And is known. The former quartz fiber has the advantage of a small transfer loss, but has the disadvantage that the connector used is very expensive since the core diameter is small and high-precision optical axis alignment is required. On the other hand, the latter plastic fiber has an advantage that an inexpensive connector (for example, a plastic molded product) having a large core diameter can be used, but a transfer loss is large and a transfer distance is at most several tens of times as compared with a quartz fiber. m.

[0003] For such a reason, in a communication system such as a home network that requires many connectors, a plastic fiber that requires only an inexpensive connector is used. In this case, the transfer distance of the plastic fiber is reduced. Due to its short length, light emitted from one end of one plastic fiber is photoelectrically converted by a light-receiving element, and this electric signal is amplified and again incident on the end of another plastic fiber to relay a plurality of plastic fibers. Thus, a distance exceeding the transferable distance of one plastic fiber is transmitted.

[0004]

However, in the above-mentioned conventional optical communication device, when transmitting over a distance exceeding the transferable distance of the plastic fiber, the optical signal of the plastic fiber is converted to an electric signal and amplified. Must be converted into an optical signal for a relay plastic fiber and transmitted, so a light receiving element, an amplifier and a light emitting element are required for each transferable distance of the plastic fiber, resulting in an increase in the price and complexity of the entire communication system. There was a problem.

[0005]

According to the present invention, a transmission range is divided into regions each of which does not exceed a transferable distance of a plastic fiber, and each region is optically communicated through a plastic fiber. Is relayed via a quartz fiber. With this configuration, it is possible to perform optical communication with a distant place using a plastic fiber without using a signal amplifying unit, and it is possible to reduce the cost and simplify the entire communication system.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In an optical communication apparatus according to the present invention, a first plastic fiber for transmitting at least an optical signal from a light emitting section and a second plastic fiber for transmitting an optical signal to at least a light receiving section.
A plastic fiber, and a quartz fiber that relays the first and second plastic fibers,
Optical coupling was performed between both ends of the quartz fiber and the first and second plastic fibers by an optical system.

[0007]

Embodiments will be described with reference to the drawings.
FIG. 1 is a configuration diagram showing an optical communication device according to a first embodiment of the present invention. As shown in FIG. 1, a light emitting element 11 is optically coupled to one end of a first plastic fiber 10a, and a light receiving element 12 is optically coupled along the way. The other end of the first plastic fiber 10a is optically coupled to the quartz fiber 14 via the optical coupler 13a.
Is optically coupled to one end of the second plastic fiber 10b via the optical coupler 13b. The light receiving / emitting element 15 and the like are optically coupled to the second plastic fiber 10b. The optical couplers 13a and 13b convert the light emitted from one end face of the first and second plastic fibers 10a and 10b and one end face of the quartz fiber 14 and diffused into the first and second plastic fibers 10a and 1b.
Ob and a lens or the like that converges light at the other end face of the quartz fiber 14.

According to such a configuration, for example, a first plastic fiber 10a and a second plastic fiber 10b are laid on each of different floors of an intelligent building, and these first and second plastic fibers 10a, 10b are laid. By relaying the space with the quartz fiber 14, optical communication with a distant place can be performed without using a signal amplifying unit (a light receiving element, an amplifier, and a light emitting element), thereby reducing the cost and simplifying the entire communication system. be able to.

FIG. 2 shows an optical communication device of a single wavelength optical LAN (local area network) as a second embodiment of the present invention. First plastic fiber 10a
A plurality of light emitting / receiving elements 1a to 6a for emitting and receiving light of the same wavelength λ are optically coupled to one end of the second plastic fiber 10b and to the same wavelength λ at one end of the second plastic fiber 10b.
A plurality of light emitting and receiving elements 1b to 6b that emit and receive the light are optically coupled. The first and second plastic fibers 10a and 10b are optically coupled to the quartz fiber 14 by optical couplers 13a and 13b. Each of the light receiving / emitting elements 1a to 6a and 1b to 6b is, for example, a personal computer or various AV devices. According to such a configuration, a plurality of light emitting and receiving elements 1a are formed by time-division multiplexing light having a wavelength λ.
6a and 1b to 6b can perform optical communication at the same time.

FIG. 3 shows a wavelength division multiplexing optical LAN as a third embodiment of the present invention. As in the above embodiments, the first and second plastic fibers 10a and 10b are composed of a quartz fiber 14 and an optical coupler 13a. , 13b. Then, the first plastic fiber 10a
, A light emitting / receiving element 1a that emits and receives light of wavelength λ1 and filters A1 and B1 are optically coupled. Further, the second plastic fiber 10b is optically coupled to filters A2 and B2 which emit and receive light of wavelength λ1. Filters A1 and B1 have wavelengths λ2 and
The light emitting / receiving elements 2a and 3a that emit and receive the light of λ3 are optically coupled, and the filters A2 and B2 respectively have the wavelengths λ2 and λ
The light emitting and receiving elements 2b and 3b that emit and receive the light of No. 3 are optically coupled. Filters A1 and A2 are both configured to transmit light of wavelength λ1 and reflect light of wavelength λ2, and filters B1 and B2 are configured to transmit light of wavelengths λ1 and λ2 and reflect light of wavelength λ3. Is configured.

According to such a configuration, on the side of the first plastic fiber 10a, the lights of the wavelengths λ1 and λ2 from the light emitting / receiving elements 1a and 2a are multiplexed by the filter A1,
Next, the light having the wavelengths λ1 and λ2 and the light having the wavelength λ3 from the light emitting / receiving element 3 are multiplexed by the filter B1, and then the lights having the wavelengths λ1, λ2 and λ3 are transmitted through the quartz fiber 14 and the optical couplers 13a and 13b. The light is transmitted to the second plastic fiber 10b. On the second plastic fiber 10b side, of these wavelengths λ1, λ2, λ3, light of wavelength λ3 is reflected by filter B2, received by light emitting / receiving element 3b, and then of wavelengths λ1, λ2 transmitted through filter B2. The light of wavelength λ2 is reflected by the filter A2 and received by the light receiving and emitting element 2b, and then the light of wavelength λ1 transmitted through the filter A2 is received by the light receiving and emitting element 1b.

The present invention is not limited to the above embodiments. For example, a light emitting element is provided on one plastic fiber, and light corresponding to the emission wavelength from the light emitting element can be detected on the other plastic fiber. The present invention can also be applied as a one-way optical communication device provided with a light receiving element.

Further, the light receiving / emitting element is not limited to one in which the light emitting element and the light receiving element are housed in one package, and the light emitting element and the light receiving element may be provided for one plastic fiber.

[0014]

The present invention is embodied in the form described above and has the following effects.

The transmission range is divided into regions that do not exceed the transferable distance of the plastic fiber, and each region performs optical communication via the plastic fiber, and the plastic fibers in each region are relayed via the quartz fiber. As a result, optical communication can be performed without using a signal amplifying means even at a long distance exceeding the transferable distance of one plastic fiber, and the cost and simplification of the entire communication system can be reduced.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating an optical communication device according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram illustrating a single-wavelength optical LAN according to a second embodiment of the present invention.

FIG. 3 is a configuration diagram illustrating a wavelength division multiplexing optical LAN according to a third embodiment of the present invention.

[Explanation of symbols]

 1a to 6a, 1b to 6b, 15 Light receiving and emitting element 10a First plastic fiber 10b Second plastic fiber 11 Light emitting element 12 Light receiving element 13a, 13b Optical coupler A1, A2, B1, B2 Filter 14 Quartz fiber

Claims (1)

[Claims] 1. A first plastic fiber for transmitting at least an optical signal from a light emitting unit, a second plastic fiber for transmitting an optical signal to at least a light receiving unit, and relaying the first and second plastic fibers. An optical communication device comprising: a quartz fiber; and optically coupling both ends of the quartz fiber and the first and second plastic fibers by an optical system.