CN2515877Y

CN2515877Y - Optical power monitor

Info

Publication number: CN2515877Y
Application number: CN01273202U
Authority: CN
Inventors: 林斌; 王明锋
Original assignee: Photop Koncent Inc
Current assignee: Photop Koncent Inc
Priority date: 2001-12-31
Filing date: 2001-12-31
Publication date: 2002-10-09
Anticipated expiration: 2011-12-31

Abstract

A luminous power monitor for optical communication is composed of a dual-optical-fibre head, a protecting sleeve and a sleeve of optical-fibre head, in which the optical fibre in dual-optical-fibre head is a common optical-fibre dual-optical-fibre head whose light-emitting surface has 8 deg. wedge angle, and a thick lens with 8 deg. wedge angle or self-focusing lens is placed behind it to make the dual-optical-fibre head be positioned on the front focus of the thick lens, the other end of the thick lens is connected with a small glass sleeve to fix a reflecting membrane, and the light-emitting surface of another thick lens is fixed on a photoelectric diode and fixed to one end of back end surface of reflecting membrane by protecting sleeve. The diaphragm is located at the intersection of the outgoing and reflected beams of the thick lens. The novel processing tool has the advantages of convenience in processing, short processing period and the like, and is low in cost.

Description

Optical power monitor

Technical field

The utility model relates to the optical power monitor that uses in a kind of optical communication field, and it is widely used in the channel power monitoring of DWDM multiplex/demultiplex, the gain monitoring of image intensifer system or the power monitoring of multichannel optical switch.

Background technology

Optical power monitor (OPTICAL POWER MONITOR) is that a kind of all-optical network system that is used for is used for the power of transmitting optical signal is monitored so that regulate and control the optical active component of handling.It has a wide range of applications in optical communication system, and it is that the light that takes out certain percentage from system signal light is used for surveying, and through opto-electronic conversion, the electric current of generation and input optical power size are linear, thus the size of signal light power as can be known.At present applied most of optical power monitor structures as shown in Figure 1,1 ' be detector, 2 ' be the optical fiber head sleeve, 3 ' be GRIN Lens, 4 ' be multimode fiber, 5 ' be monomode fiber.Be coated with reflectance coating at GRIN Lens 3 ' front end face.From the flashlight of monomode fiber 5 ' come out enter into GRIN Lens 3 ', GRIN Lens 3 ' the most of light transmission of front end face, the reflection of sub-fraction light, enter into multimode fiber 4 ', through multimode fiber 4 ' be coupled into detector 1 ' in.The characteristics of this structure exactly can be detector 1 ' be placed on the optional position flexibly, but structure is complicated, the assembling difficulty, and emergent light is a Gaussian beam.

Summary of the invention

The purpose of this utility model is to be to provide a kind of simple in structure, cheap power monitor.

This novel concrete structure is: the optical fiber in the double optical fiber head is ordinary optic fibre, 8 ° of angles of wedge are worn in the bright dipping of double optical fiber head, 8 ° of angle of wedge thick lenses or GRIN Lens are placed in its back, double optical fiber head is positioned on this thick lens front focus, the other end of this thick lens is connected with little glass bushing, with the fixation reflex diaphragm; The exiting surface of another thick lens is fixed on the photodiode, and is fixed on rear end face one end of reflection diaphragm by metal bridge, and two thick lenses have identical material.Reflection diaphragm is positioned on the intersection point of the outgoing beam of thick lens and folded light beam.The exiting surface of thick lens can adopt the radius of curvature curved surface identical with the incident light plane radius of curvature of another thick lens.The diaphragm front end face is coated with highly reflecting films, and rear end face is coated with anti-reflection film and diaphragm thickness less than 1mm.The double optical fiber head exiting surface, the front/rear end of two thick lenses all is coated with anti-reflection film.

Description of drawings

Fig. 1 is the prior art optical structure chart.

Fig. 2 is this novel optical structure chart (scheme one).

Fig. 3 is this novel optical structure chart (scheme two).

Fig. 4 is this novel another scheme assembly structure figure.

Fig. 5 is this new embodiment assembly structure figure.

Embodiment

The utility model is an optical power monitor a kind of simple in structure, cheap.For adapting to different demands, this novel implementation is to get a fraction of transmittance, is coupled into photodiode and is used for surveying, and all the other most of light reflected backs enter another root optical fiber, and emergent light still transmits in optical fiber.After GRIN Lens (8 ° of angle of wedge thick lenses), become the collimate in parallel light beam from the input light of double optical fiber head one end incident, and Fresnel reflection takes place on diaphragm, wherein most of energy is reflected back toward the other end output of double optical fiber head, the sub-fraction transmission potential is assembled through facing thick head mirror directly, received by photodiode, produce electric current.Size of current and input optical power size are linear dependence, thereby can carry out effective monitoring to the input optical power size.As Fig. 2, shown in Figure 3.

With scheme two is example, and as shown in Figure 3, double optical fiber head 3 is common glass material, and its outgoing end face is in vertical direction with 8 ° of angles of wedge, and is positioned on the front focus of 8 ° of angle of wedge thick lenses 10.The parallel axis device that is symmetrical in of two optical fiber wherein.From propagating a segment distance the air gap after, the light of an optical fiber outgoing will incide on 8 ° of angle of wedge thick lens 10 front end faces.

8 ° of angle of wedge thick lenses 10 are the optical material of refractive index n=1.744742, and it mainly makes from the diverging light of focus incident and becomes the collimate in parallel light beam.Its front end face can effectively prevent the high return loss that Fresnel reflection produces equally in vertical direction with 8 ° of angles of wedge.Other 8 ° of angle of wedge thick lenses 10 are glued together with double optical fiber head 3.

Reflection diaphragm 9 is placed on the intersection point of the outgoing beam of 8 ° of angle of wedge thick lenses 10 and folded light beam, and its front surface 13 plates high-reflecting film, and rear surface 12 is an anti-reflection film.Return from the diaphragm front surface reflection that will be reflected of the most of energy of the collimate in parallel light beam of 8 ° of angle of wedge thick lenses, 10 rear surfaces, 12 outgoing, enter another root optical fiber by 8 ° of angle of wedge thick lenses 10 and air-gap.

It is identical with radius of curvature with 8 ° of angle of wedge thick lens 10 materials to face thick lens 8 directly.Facing thick lens 8 rear end faces 16 directly is the right angle face and is close on the photodiode 7 plane windows.Incide on the thick lens 8 by air-gap from the transmitted light beam of reflection diaphragm 9 rear surfaces, 12 outgoing, received by photodiode 7 after thick lens 8 is assembled by facing directly again,, produce electric current output through photodiode 7 opto-electronic conversion.

Fig. 2 is this novel embodiment one, and wherein double optical fiber head 3 exiting surfaces adopt GRIN Lens 5, and reflection diaphragm 9 is close to the light output end of GRIN Lens 5.

Fig. 3 is this novel embodiment two, and wherein double optical fiber head 3 exiting surfaces are placed with the thick lens 10 with 8 ° of angles of wedge, and thick lens 10 exiting surfaces are that radius of curvature is the curved surface of r=1.419mm.

Fig. 5 is another specific embodiment of the utility model, and wherein 1 is protective sleeve, and 2 is the optical fiber head sleeve, and 3 is double optical fiber head; 4 is metal bridge, and 5 is thick lens, and 6 is big glass bushing, and 7 is photodiode; 8 is the thick lens head, and 9 is reflection diaphragm, and 10 is thick lens, and 11 is little glass sleeve.

Double optical fiber head 3 is common glass material, and its outgoing end face is in vertical direction with 8 ° of angles of wedge, and is positioned on the front focus of thick lens 10.The parallel axis that is symmetrical in of two optical fiber is wherein placed.From propagating a segment distance the air gap after, the light of an optical fiber outgoing will incide on thick lens 8 front end faces.

Thick lens 10 is the optical material of refractive index n=1.744742, and it mainly makes from the diverging light of focus incident and becomes the collimate in parallel light beam.Its front end face can effectively prevent the high return loss that luxuriant and rich with fragrance alunite oppositely produces equally in vertical direction with 8 ° of angles of wedge.Its other end is that radius of curvature is the curved surface of r=1.419.Thick lens 10 is glued together with double optical fiber head 3 in addition.

Reflection diaphragm 9 is fixed on by little glass bushing 11 on the intersection point of the outgoing beam of thick lens 10 and folded light beam, and it is 95% high-reflecting film that its front surface 13 plates reflectivity, and rear surface 12 is an anti-reflection film.Return from diaphragm 9 front surface reflections that will be reflected of the most of energy of the collimate in parallel light beam of thick lens 10 rear end outgoing, enter another root optical fiber by thick lens 10 and air-gap, this reflected signal continues to transmit in light path.

Thick lens 8 is identical with radius of curvature with thick lens 10 materials, as shown in Figure 5.Thick lens 8 rear end faces are that right angle face 16 is hidden and is close on the photodiode 7 plane windows.Incide on the thick lens 8 by air-gap from the transmitted light beam of reflection diaphragm 9 rear surface outgoing, assemble the back by thick lens 8 again and received,, produce electric current output through photodiode 7 opto-electronic conversion by photodiode 7.The thickness that thick lens 8 and thick lens 10 front-backs all are coated with anti-reflection film, reflection diaphragm 9 is that the effect of 1mm is better.

Claims

1. optical power monitor, form by double optical fiber head, protective sleeve, optical fiber head sleeve etc., it is characterized in that: the optical fiber in the double optical fiber head is that 8 ° of angles of wedge are worn in the bright dipping of ordinary optic fibre double optical fiber head, 8 ° of angle of wedge thick lenses (10) or GRIN Lens (5) are placed in its back, double optical fiber head is positioned on this thick lens (10) front focus, the other end of this thick lens (10) is connected with little glass bushing, with the fixation reflex diaphragm; The exiting surface of another thick lens (8) is fixed on the photodiode, and be fixed on rear end face one end of reflection diaphragm by metal bridge, thick lens (10) has identical material with thick lens (8), and reflection diaphragm is positioned on the intersection point of the outgoing beam of thick lens (10) and folded light beam.

2. optical power monitor according to claim 1 is characterized in that: the exiting surface of thick lens (10) can adopt the identical curved surface of incident light plane radius of curvature of radius of curvature and thick lens (8), or to adopt the exiting surface of thick lens (10) be the right angle face.The incidence surface of thick lens (8) is a curved surface, and the emergent light face that also can adopt thick lens (10) is a curved surface, and the incident light plane of thick lens (8) is the right angle face.

3. optical power monitor according to claim 1 and 2 is characterized in that: the reflection diaphragm front end face is coated with highly reflecting films, and rear end face is coated with anti-reflection film and diaphragm thickness less than 1mm.

4. optical power monitor according to claim 1 is characterized in that: the double optical fiber head exiting surface, thick lens (10) all is coated with anti-reflection film with the front/rear end of thick lens (8).