CN105988167A

CN105988167A - Unidirectional optical power detector

Info

Publication number: CN105988167A
Application number: CN201510063058.5A
Authority: CN
Inventors: 韩朝阳
Original assignee: Individual
Current assignee: Individual
Priority date: 2015-02-08
Filing date: 2015-02-08
Publication date: 2016-10-05

Abstract

The invention relates to a unidirectional optical power detector which comprises an input optical fiber, an output optical fiber, a dark optical fiber, a collimating lens, a light splitter or a light splitting coating, an imaging lens, and a photoelectric detector assembly including a photoelectric detector chip. The dark optical fiber and the imaging lens are utilized to separate forward light from the input optical fiber from backward light from the output optical fiber with a larger interval, and blackening is carried out on the inner wall of the photoelectric detector assembly or a light absorbing material is coated on the inner wall of the photoelectric detector assembly to prevent the backward light from the output optical fiber from entering the photoelectric detector chip and further influencing the measuring precision. The unidirectional optical power detector is high in unipolarity, easy to produce and low in cost.

Description

Unidirectional optical power detector

Technical field

The present invention relates to the photodetector of a kind of optical communication, particularly relate to a kind of unidirectional optical power detector (Uni-directional Tap Optical Power Monitor).

Background technology

Optical power detector is widely used in optical fiber telecommunications system, the energy of fiber-optic signal is carried out on-line water flushing, thus realizes the monitoring to optical signal and management.Traditional optical power detector generally comprises input and output optical fibre, a collimating lens, a light splitting piece or light splitting coating and an optical detector component.The light reflected by output optical fibre is not limited by such optical power detector so that the measurement of luminous power be easier to reflected return light impact.

On February 19th, 2008 7,333, No. 693 optical power detectors disclosing a kind of improvement of U.S. Patent No., the light from input optical fibre and the light from output optical fibre are oriented slightly different directions by an imaging len.Unfortunately, the reflection light entering optical detector component from output optical fibre is still likely to enter detector chip after multiple reflections, thus causes too high power reading.

Notification number at December in 2014 bulletin on the 03rd is CN 102, and in the Chinese patent of 043,209 B, Yang Yatao et al. proposition mask or shaping piece stop any light coming from output optical fibre to enter into the scheme of photo detector chip.Unfortunately, mask or shaping piece have blocked the photosurface of a part of photo detector chip simultaneously.To a certain extent, this photo-detector being equivalent to employ little photosurface.Stoping from while the light of output optical fibre, to the coupling of the light from input optical fibre it is also proposed that higher requirement, thus adding production time and product cost.

In the patent of invention that notification number is CN 201100946Y of bulletin on August 13rd, 2008, thunder and clear proposition use the integration scenario of the photodetector of the double optical fiber head of big spacing, short focal length lens, glass wedge optical correction device and little photosurface to realize will not interfere with monitoring signal to be measured from the reverse optical signal of outfan.In the claims, thunder and the clear double fiber optic hub spacing proposing double optical fiber head are less than 80 microns more than the photosurface of 0.126mm and detector.In addition to production time that the detector of little photosurface brings and product cost problem, the double optical fiber pitch more than 0.126mm the most easily bring the problem of asymmetry, thus bring bigger loss, even more so that the unglazed output of outfan time serious.

Summary of the invention

It is an object of the invention to overcome the defect of prior art, it is provided that a kind of high-precision unidirectional optical power detector.It realizes being as dark fibre by piece same optical fiber of insertion between input optical fibre and output optical fibre, is ensureing input optical fibre and the output optical fibre symmetric spacing simultaneously added between input optical fibre and output optical fibre for optical axis；Make the forward light from input optical fibre of entrance photodetector assembly make big spacing with the backlight from output optical fibre by imaging len again to separate and enter into photoelectric detector chip from the light of input optical fibre affect certainty of measurement to stop.

Therefore, the unidirectional optical power detector that the present invention relates to includes: input optical fibre, is used for launching optical signal；Output optical fibre, is used for exporting optical signal；Dark fibre, is between input optical fibre and output optical fibre, for ensureing that input optical fibre and output optical fibre are for the symmetry of optical axis the spacing that increases between input optical fibre and output optical fibre；Collimating lens, for collimation from input optical fibre and the optical signal of output optical fibre；Light splitting piece or light splitting coating, the light for self-focus lens in the future carries out light splitting, and a part (1% ~ 10%) transmission also eventually enters into photodetector, and another part reflection also exports from another root optical fiber；Imaging len, is used for assembling the light of above-mentioned Part I (1% ~ 10%), and is spatially separating the forward light from input optical fibre and the backlight from output optical fibre；And photodetector assembly, it includes detector chip, for receiving the light entering chip the measurement providing luminous power.

Accompanying drawing explanation

The structural representation of the unidirectional optical power detector of Fig. 1: the present invention.

Fig. 2: optical fiber arrangement schematic diagram.

Fig. 3: basic structure optical principle schematic diagram.

The forward light path schematic diagram of the unidirectional optical power detector of Fig. 4: the present invention.

The reverse optical path schematic diagram of the unidirectional optical power detector of Fig. 5: the present invention.

Detailed description of the invention

Below in conjunction with the accompanying drawings, the unidirectional optical power detector of the present invention is described in further detail.In the accompanying drawings, identical reference represents identical parts, feature or structure.

Such as Fig. 1, the unidirectional optical power detector of the present invention includes input optical fibre 101, output optical fibre 103, dark fibre 102, collimating lens 200, light splitting piece or light splitting coating 210, imaging len 300 and photodetector assembly 400, and it includes detector chip 410.

As in figure 2 it is shown, dark fibre 102 is between input optical fibre 101 and output optical fibre 103, three is the most adjacent.The core diameter of input optical fibre 101, output optical fibre 103 and dark fibre 102 is 125 microns, thus the center of input optical fibre is 250 microns to the spacing distance at the center of output optical fibre.

As it is shown on figure 3, input optical fibre 101 is equal with the spacing distance of output optical fibre 103 to optical axis 11 to the spacing distance of optical axis 11, it is symmetrical；Collimating lens 200 and imaging len 300 are also symmetrical relative to optical axis 11.The light launched from input optical fibre 101 port AA is formed collimated light by collimating lens 200, then is imaged in AA by imaging len 300 convergence "；The light launched from output optical fibre 103 port BB is formed collimated light by collimating lens 200, imaging len 300 assemble and image in BB ".AA " and BB " between center spacing distance equal to the center of input optical fibre to the spacing distance at the center of output optical fibre, be 250 microns.

The unidirectional optical power detector of the present invention is on the basis of structure shown in Fig. 2, between collimating lens 200 and imaging len 300, insert light splitting piece or the direct end face at collimating lens 200 plates light splitting coating 210, being used for a light part for input optical fibre being reflected and exporting from output optical fibre, another part is transmitted into imaging len 300.At imaging len 300 and imaging point AA " between place photodetector assembly 400 include detector chip 410, be used for receive the light come through light splitting piece or light splitting coating 210 via imaging len 300.Detector chip 410 is preferably placed in AA " side and make photosurface center and AA " the line of centres parallel with optical axis 11.

As shown in Figure 4, the light (forward light) launched from input optical fibre 101 is formed collimated light A by collimating lens 200_C, after light splitting piece or light splitting coating 210 light splitting, a part of light A_FOutput optical fibre 103 is converged to through collimating lens 200 after reflection；Another part A_T(1% to 10%) is entered photodetector assembly 400 by imaging len 300 through light splitting piece or light splitting coating 210 and arrives detector chip 410.

As it is shown in figure 5, the light (backlight) from output optical fibre 103 transmitting is formed collimated light B by collimating lens 200_C, after light splitting piece or light splitting coating 210 light splitting, a part of light B_FInput optical fibre 101 is converged to through collimating lens 200 after reflection；Another part B_T(imaged in BB through light splitting piece or light splitting coating 210 by imaging len 300 ".For the detector chip of the photosurface diameter 300 microns of normally used low cost, BB " center be up to away from 100 microns from the edge of photosurface so that the light that transmission comes arrives the probability of detector chip 410 and is substantially reduced.Absorb and backlight can be stoped by the inwall of photodetector assembly 400 being done blackening process or coating light absorbing material further to enter the precision that detector chip impact is measured from the backlight of output optical fibre.

Claims

1. the unidirectional optical power detector that the present invention relates to includes: input optical fibre, output optical fibre, dark fibre, collimating lens, light splitting piece or light splitting coating, imaging len and include the photodetector assembly of detector chip.

2. the unidirectional optical power detector limited according to claim 1, it is characterised in that described dark fibre is between input optical fibre and output optical fibre.

3. the unidirectional optical power detector limited according to claim 1, it is characterised in that described input optical fibre and output optical fibre are symmetrical relative to optical axis.

4. the unidirectional optical power detector limited according to claim 1, it is characterised in that described detector chip is placed between imaging len and imaging point and has a certain degree of skew relative to optical axis.

5. the unidirectional optical power detector limited according to claim 1, it is characterised in that the inwall of described detector assembly makees blackening process or coating light absorbing material.