JPS60414A - Two input light photodetecting device - Google Patents

Abstract

PURPOSE:To obtain a small-sized two input light photodetecting device having a high reliability by incorporating the second light source in the same airtight package as a photodetector, and making a light from the first light source incident to the photodetector in the airtight package from an optical fiber. CONSTITUTION:A photodetector 13 and a light emitting element 15 are incorporated in the same metallic airtight package 12. A light from the element 15 is reflected directly or irregularly in the package 12, and thereafter, made incident to the photodetector 13. On the other hand, a light from another light source is emitted from an optical fiber 10, and made incident to the photodetector 13 through a photodetecting window 11. In this regard, the fiber 10 is fixed to the package 12 by supporting metallic fittings, etc. A modulating signal of a light emitted from the element 15 is inputted from a signal input terminal 16, and a modulating signal of a light photodetected by the photodetector 13 is fetched from a signal output terminal 14. In this way, a small-sized two input light photodetecting device which can raise its reliability is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field of the Invention The present invention relates to a two-man power light receiving bag WK that can be miniaturized and improve reliability in a two-man power light receiving device for optical communication.

(b) Conventional technology and problems FIG. 1 is a schematic diagram of a conventional two-manpower light receiving device.

In the figure, 1 and 2 are input lights, 3 and 4 are optical fibers, 5 is a lens, 6 is a light receiving window, 7 is a light receiving element, 8 is a signal output terminal, and 9 is an airtight package.

In the two-power light receiving device shown in FIG. The signals obtained by modulating the input lights 1 and 2 are sent to the light receiving element 7.
The signal is converted into an electrical signal and taken out from the signal output terminal 8.

However, this two-manpower light receiving device has the disadvantage that it becomes large because the relative positions of the optical fiber 3° 4, lens 5, and light receiving element 7 must be precisely adjusted and fixed, and even if fixed, the lens 5 Since the beam is focused at a distance, the beam position and direction are likely to fluctuate due to temperature changes, vibrations, etc., resulting in low reliability.

(c) Object of the Invention In view of the above-mentioned drawbacks, an object of the present invention is to provide a two-manpower light receiving device that can be downsized and improved in reliability.

(d) Structure of the Invention In order to achieve the above object, the present invention provides a dual-power light receiving device in which light from a first light source and a second light source is received by a light receiving element. The light receiving element is housed in the same airtight pano cage as the light receiving element, and the light from the first light source enters the light receiving element through an optical fiber without using a lens.

(e) Examples of the invention An embodiment of the present invention will be described with reference to the drawings.

FIG. 2 is a sectional view of a two-manpower light receiving device according to an embodiment of the present invention.

In the figure, 10 is an optical fiber, 11 is a light receiving window, 12 is an airtight package, 13 is a light receiving element, 14 is a signal output terminal, 15 is a light emitting element (second light source), and 16 is a signal input terminal.

In FIG. 2, the light-receiving element 13 and the light-emitting element 15 are housed in the same airtight package 12 with extra ends, and the light-emitting element 15
The reflected light enters the light receiving element 13 either directly or after 1d diffuse reflection within the airtight package 12. On the other hand, light from another light source (not shown) is emitted from the optical fiber 10 and is emitted from the light receiving window 1.
1 and enters the light receiving element 13. Incidentally, the optical fiber 10 is fixed to the airtight package 12 with a support fitting or the like.

The modulation signal of the light emitted from the light emitting element 15 is inputted from the signal input terminal 16, and the modulation signal of the light received by the light receiving cable 13 is taken out from the signal output terminal 14.

In the two-manpower light receiving device shown in FIG. 2, the light emitting element 15, which is one light source, is built into the same airtight buff cage 12 as the light receiving element 13, so light from other light sources is input first and is connected to the optical fiber 10. Therefore, the light receiving element 13 can be directly used without using a lens.
Since no lens is used, the beam position and direction do not fluctuate even if there is temperature change vibration, which increases reliability.

<f) Effects of the Invention As explained in detail above, according to the present invention, a two-manpower light can be made structurally similar to a one-manpower light, and since there is no need to worry about using a condensing lens, it is possible to downsize and improve reliability. This has the effect of providing a two-manpower light receiving device that can improve the performance.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a conventional two-manpower light receiving device, and FIG. 2 is a sectional view of a two-manpower light receiving device according to an embodiment of the present invention. In the figure, 1 and 2 are input lights, 3 and 4.10 are optical fibers, 5 is a lens, and 6. If is a light receiving window, 7.13 is a light receiving element, 8.
14 is a signal output terminal, 9.12 is an airtight package, 15
indicates a light emitting element, and 16 indicates a signal input terminal. Man 1 figure δ Figure 2

Claims (1)

[Claims] In a dual-power light receiving device in which a light receiving element receives light from a first light source and a second light source, the second light source is built in the same airtight package as the light receiving element, and the second light source is housed in the same airtight package as the light receiving element. A two-man power light receiving device characterized in that the light is made to enter a light receiving element in the airtight pancase through an optical fiber.