CN219496698U

CN219496698U - Optical fiber sensor

Info

Publication number: CN219496698U
Application number: CN202320055784.2U
Authority: CN
Inventors: 黄波
Original assignee: Shenzhen Xhorse Electronics Co Ltd
Current assignee: Shenzhen Xhorse Electronics Co Ltd
Priority date: 2023-01-09
Filing date: 2023-01-09
Publication date: 2023-08-08
Anticipated expiration: 2033-01-09

Abstract

The application provides an optical fiber sensor comprising an amplifying part arranged in a shell and an optical fiber part extending from the shell; the amplifying part comprises a light source, a lens and a detector; the optical fiber part comprises a transmitting optical fiber and a receiving optical fiber; the light source, the lens and the emitting optical fiber are sequentially arranged along the direction of the light projection optical axis; the light source is used for generating signal light, and the signal light is transmitted along the direction of the light projecting optical axis after being transmitted by the transmitting optical fiber; the receiving optical fiber is an optical fiber beam combiner, and the detector is arranged at the output end of the optical fiber beam combiner; the input end of the optical fiber beam combiner is used for receiving and transmitting signal light emitted by the optical fiber, and the signal light enters the detector after being transmitted by the optical fiber beam combiner. According to the optical fiber sensor, the light receiving area of the receiving optical fiber is increased through the optical fiber beam combiner, the light emitting area of the receiving optical fiber is reduced, the working distance of the optical fiber sensor can be increased, the detection area of the used detector is reduced, and the volume of an amplifying part of the optical fiber sensor is reduced.

Description

Optical fiber sensor

Technical Field

The utility model relates to the field of optical sensors, in particular to an optical fiber sensor.

Background

Currently, in the automatic production lines of filling, LCD assembly (LCD, liquid crystal display), automobile assembly, PCB, print packaging and the like, an optical fiber sensor is often adopted to judge the in-place and presence of a workpiece. On a production line with a large workpiece size, the distance to be detected is large, which requires a large working distance of the optical fiber sensor.

In the prior art, an optical fiber bundle formed by a plurality of optical fibers is generally used as a receiving optical fiber, so that the light receiving area of the receiving optical fiber is increased, the light receiving efficiency is improved, and a larger working distance is obtained for the optical fiber sensor. However, after increasing the light receiving area of the receiving optical fiber, the detector matched with the receiving optical fiber also needs to increase the detection area at the same time, so that the problem of overlarge whole volume of the optical fiber detector is caused, the area of the optical fiber detector is limited, and the increase of the working distance is limited.

Disclosure of Invention

The utility model aims at: aiming at the defects of the prior related art, the optical fiber sensor is provided, and the working distance of the optical fiber sensor is increased on the premise of using the existing detector with the detection area or smaller area, so that the requirement of long-distance detection is met.

In order to achieve the above purpose, the present utility model adopts the following technical scheme:

the optical fiber sensor includes an amplifying section mounted in a housing, and an optical fiber section extending from the housing.

The amplifying part comprises a light source, a lens and a detector; the optical fiber section includes a transmitting optical fiber and a receiving optical fiber.

The light source, the lens and the emitting optical fiber are sequentially arranged along the direction of the light projection optical axis; the light source is used for generating signal light, and the signal light propagates along the light projection optical axis direction after being emitted by the emitting optical fiber.

The receiving optical fiber is an optical fiber beam combiner, and the detector is arranged at the output end of the optical fiber beam combiner; the input end of the optical fiber beam combiner is used for receiving and transmitting signal light emitted by the optical fiber, and the signal light enters the detector after being transmitted by the optical fiber beam combiner.

When the light source is used, light rays emitted by the light source are coupled into the emitting optical fiber from the incident surface of the emitting optical fiber through the lens, a beam of signal light is formed and propagates along the emitting optical fiber, and then the signal light propagates along the direction of the light projecting optical axis after being emitted by the emitting surface of the emitting optical fiber. The signal light irradiates the input end of the optical fiber beam combiner after passing through the position to be detected, enters the optical fiber beam combiner, enters the detector after being transmitted by the optical fiber beam combiner, forms light spots on the detection surface of the detector, and emits corresponding electric signals after the detector detects the light spots.

By adopting the technical scheme, compared with the prior art, the utility model has the following beneficial effects:

the optical fiber sensor provided by the utility model adopts the optical fiber beam combiner as the receiving optical fiber, the input end of the optical fiber beam combiner receives the signal light, and the light receiving area of the receiving optical fiber is enlarged to improve the light receiving efficiency, so that the working distance of the optical fiber sensor is increased. Meanwhile, the optical fiber sensor provided by the utility model reduces the emergent area of the signal light after being transmitted by the receiving optical fiber through the optical fiber combiner, reduces the spot area formed on the detector, reduces the detection area of the detector used and reduces the volume of the amplifying part of the optical fiber sensor.

Drawings

FIG. 1 is a schematic diagram of a fiber optic sensor according to embodiment 1 of the present utility model;

FIG. 2 is a schematic diagram of a prior art receiving fiber;

FIG. 3 is a schematic diagram of an optical fiber combiner according to embodiment 1 of the present utility model;

FIG. 4 is a schematic diagram showing the operation of the optical fiber sensor in embodiment 2 of the present utility model;

fig. 5 is a schematic diagram showing the operation of the optical fiber sensor in embodiment 3 of the present utility model.

Wherein, 1: a light source; 2: a lens; 3: a detector; 4: an emission optical fiber; 5: receiving an optical fiber; 6: a signal light; 7: detecting a station; 8: a housing; 9: a workpiece; 41: an incidence surface; 42: an emission surface; 51: an output end; 52: an input terminal.

Detailed Description

It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the utility model.

The following description of the embodiments of the present utility model will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all embodiments of the utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without any inventive effort, are intended to be within the scope of the utility model.

It should be noted that, in the embodiments of the present utility model, all directional indicators (such as up, down, left, right, front, and rear … …) are merely used to explain the relative positional relationship, movement conditions, and the like between the components in a specific posture (as shown in the drawings), if the specific posture is changed, the directional indicators correspondingly change, and the connection may be a direct connection or an indirect connection.

In addition, the technical solutions of the embodiments may be combined with each other, but it is necessary to base that the technical solutions can be realized by those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should be considered to be absent and not within the scope of protection claimed in the present utility model.

Example 1

The present embodiment provides an optical fiber sensor including an amplifying portion mounted in a housing, and an optical fiber portion extending from the housing; the amplifying part comprises a light source 1, a lens 2 and a detector 3; the optical fiber section includes a transmitting optical fiber 4 and a receiving optical fiber 5. Fig. 1 is a schematic structural diagram of an optical fiber sensor according to the present embodiment. Wherein the light source 1, the lens 2 and the detector 3 are arranged in a housing 8 to form an amplifying part of the optical fiber sensor, the light source 1 is used for generating an optical signal, the lens 2 is used for coupling the optical signal into an incident end of the transmitting optical fiber 4, and the detector 3 is used for receiving the optical signal and outputting an electric signal which is amplified after being processed by a circuit so as to be identified. The transmitting optical fiber 4 and the receiving optical fiber 5 pass through the housing 8 and are connected to the lens 2 and the detector 3, respectively.

The light source 1 is disposed on the optical axis of the lens 2, and the light source 1 may be one or more of a Light Emitting Diode (LED), a Laser Diode (LD) or a Vertical Cavity Surface Emitting Laser (VCSEL). For example, a single light emitting diode may be used as the light source 1, or a plurality of light emitting diodes may be used as the light source 1. The light source 1 is arranged on the optical axis of the lens 2, so that the light intensity of the light collected by the lens 2 can be improved, and the detection range of the optical fiber sensor can be increased.

The light source 1, the lens 2 and the emitting optical fiber 4 are sequentially arranged along the light projection optical axis direction; the light source 1 is used for generating signal light 6, and the signal light 6 propagates along the light projecting optical axis direction after being emitted by the emitting optical fiber 4. The direction of the light projecting optical axis is the direction in which the transmitting optical fiber 4 needs to transmit the signal light 6. The entrance face 41 of the emitting fiber 4 is perpendicular to the optical axis of the lens 2 and the emission face 42 of the emitting fiber 4 is perpendicular to the projection optical axis. After the light source 1 emits light, the lens 2 couples part of the light into the emitting optical fiber 4 to form the signal light 6. One end of the emitting surface 42 of the emitting optical fiber 4 may be fixed by a fastener such that the emitting surface 42 of the emitting optical fiber 4 is perpendicular to the projection optical axis.

As shown in fig. 2, a schematic structure of a receiving fiber in the prior art is shown. The receiving optical fiber 5 is an optical fiber bundle formed by a plurality of optical fibers, and compared with a single optical fiber, the cross sectional areas of the incident end and the emergent end of the receiving optical fiber 5 are increased, so that the light receiving area is increased, and the optical fiber sensor obtains a larger working distance. However, this also results in an increase in the area of the light spot formed by the receiving optical fiber 5 on the detector 3, and the detector 3 to be matched with the receiving optical fiber needs to increase the detection area at the same time, so that the problem of overlarge overall volume of the optical fiber detector is caused, and the increase in the working distance of the optical fiber detector is limited due to the area of the detector 3.

In this embodiment, the receiving optical fiber 5 is an optical fiber combiner, and the detector 3 is disposed at an output end 51 of the optical fiber combiner; the input end 52 of the optical fiber combiner is used for receiving the signal light 6 emitted by the emitting optical fiber 4, and the signal light 6 enters the detector 3 after being transmitted by the optical fiber combiner and is monitored by the detector 3. Fig. 3 is a schematic structural view of the optical fiber combiner. The input end 52 of the optical fiber combiner is a light receiving surface, and the light receiving surface is disposed on the optical path of the signal light 6 emitted by the emitting optical fiber 4. The cross-sectional area of the output end 51 of the optical fiber combiner is sharply reduced, and the signal light 6 transmitted by the optical fiber combiner can form smaller light spots on the detector 3, so that compared with the prior art, the embodiment can obtain larger working distance by increasing the size of the light receiving surface of the receiving optical fiber on the premise of selecting a detector with smaller detection area.

The optical fiber sensor provided in this embodiment adopts the optical fiber combiner as the receiving optical fiber 5, receives the signal light 6 emitted by the emitting optical fiber 4 through the input end 52 of the optical fiber combiner, and increases the light receiving area to improve the light receiving efficiency, thereby increasing the working distance of the optical fiber sensor. Meanwhile, in the optical fiber sensor provided by the utility model, the light spot area formed on the detector 3 after the signal light 6 is transmitted by the receiving optical fiber 5 is reduced through the optical fiber combiner, the detection area of the detector 3 is reduced, and the volume of an amplifying part of the optical fiber sensor is reduced.

Example 2

This embodiment is a further improvement according to embodiment 1, wherein in the optical fiber sensor provided in this embodiment, the lens 2 is selected from one or more of a spherical mirror, an aspherical mirror, a parabolic mirror, or a total internal reflection lens 2. The lens 2 may be one of the lenses 2, or may be a lens group composed of a plurality of lenses 2.

The optical fiber sensor provided in this embodiment is a reflective optical fiber sensor, as shown in fig. 4, which is a schematic working diagram of the optical fiber sensor in this embodiment, where the transmitting optical fiber 4 and the optical fiber combiner 5 are disposed at one side of the detection station 7, and an input end 52 of the optical fiber combiner is configured to receive the reflected signal light 6. The end of the emitting surface 42 of the emitting optical fiber 4 and the input end 52 of the optical fiber combiner are packaged together to form an optical fiber bundle for receiving the signal light 6 reflected by the workpiece 9 in the detection station 7. Wherein the workpiece 9 passes the inspection station 7 during movement. The distance of the optical fiber bundle from the work 9 is set to L. When the workpiece 9 does not reach the detection station 7, the signal light 6 emitted by the emission surface 42 of the emission optical fiber 4 passes through the detection station 7 along a straight line, cannot be received by the input end 52 of the optical fiber combiner, and no signal light 6 irradiates the detector 3, so that the detector 3 outputs a weaker electric signal. When the workpiece 9 reaches the detection station 7, the signal light 6 emitted by the emitting surface 42 of the emitting optical fiber 4 irradiates on the workpiece 9, the signal light 6 is diffusely reflected, the input end 52 of the optical fiber beam combiner receives the diffusely reflected signal light 6, and then the signal light 6 is transmitted and irradiated on the detector 3, and at this time, the electric signal output by the detector 3 becomes significantly stronger.

The optical fiber sensor provided in this embodiment is a reflective optical fiber sensor, and combines the input end 52 of the optical fiber combiner and the transmitting optical fiber 4 into one optical fiber bundle, so that the installation is easier, and compared with the existing diffuse reflection optical fiber sensor, the light receiving surface of the optical fiber combiner in this embodiment is larger, and more signal lights 6 reflected by diffuse reflection can be received, so that a larger working distance can be obtained.

Example 3

This embodiment is a further improvement according to embodiment 1, wherein the detector 3 is selected from a Photodiode (PD), a position detector (PSD), a Charge Coupled Device (CCD) or a Complementary Metal Oxide Semiconductor (CMOS) in the optical fiber sensor provided in this embodiment. The output end 51 of the optical fiber combiner is perpendicular to the detection surface of the detector 3, and the cross-sectional area of the output end 51 of the optical fiber combiner is smaller than or equal to the detection area of the detection surface of the detector 3.

The optical fiber combiner can increase the number of optical fibers or the diameter of the optical fibers constituting the optical fiber combiner according to the requirement of the inspection distance, thereby increasing the working distance. Preferably, an optical fiber combiner with a smaller cross-sectional area of the output end 51 may be selected, so that the area of the light spot formed on the detector 3 by the signal light 6 may be reduced, and the optical fiber sensor may use the detector 3 with a smaller volume.

The input end 52 of the optical fiber combiner is an optical fiber bundle formed by N optical fibers, and N is more than or equal to 2; the output end 51 of the optical fiber combiner is an optical fiber; the fiber bundle of the input end 52 has a flat light receiving surface. The optical fiber is made of glass or polymer.

The transmitting optical fiber 4 and the receiving optical fiber 5 are respectively arranged at two sides of the detection station 7, and the transmitting surface 42 of the transmitting optical fiber 4 and the light receiving surface of the optical fiber combiner are coaxially arranged. Wherein the workpiece 9 passes the inspection station 7 during movement.

The optical fiber sensor provided in this embodiment is an opposite-type optical fiber sensor, as shown in fig. 5, which is a working schematic diagram of the optical fiber sensor in this embodiment, and the distance L between the emitting surface 42 of the emitting optical fiber 4 and the light receiving surface of the optical fiber combiner is coaxially installed at two sides of the detection station 7. When the workpiece 9 does not reach the detection station 7, the signal light 6 emitted by the emitting surface 42 of the emitting optical fiber 4 can be received by the light receiving surface of the optical fiber combiner and then is transmitted to the detector 3, and the detector 3 outputs a larger electric signal at the moment; when the workpiece 9 reaches the detection station 7, the signal light 6 emitted by the emitting surface 42 of the emitting optical fiber 4 is gradually blocked by the workpiece 9, and the light intensity received by the light receiving surface of the optical fiber combiner is significantly changed, so that the electric signal output by the detector 3 is significantly weakened.

The optical fiber sensor provided in this embodiment is a correlation optical fiber sensor, and the cross-sectional area of the output end 51 of the optical fiber combiner is the sum of the cross-sectional areas of a plurality of optical fibers, so that the optical fiber sensor has a larger light receiving surface and light receiving efficiency, and thus has a larger working distance. The cross-sectional area of the output end 51 of the optical fiber combiner is reduced, so that the area of a light spot formed by the signal light 6 on the detector 3 is smaller, and the small-area detector 3 can meet the working requirement of the optical fiber sensor, thereby reducing the volume of an amplifying part of the optical fiber sensor.

The foregoing description is only of the preferred embodiments of the present utility model and is not intended to limit the scope of the utility model, and all equivalent structures or equivalent processes using the descriptions and drawings of the present utility model or directly or indirectly applied to other related technical fields are included in the scope of the utility model.

Claims

1. An optical fiber sensor comprising an amplifying section mounted in a housing and an optical fiber section extending from the housing;

the amplifying part comprises a light source (1), a lens (2) and a detector (3); the optical fiber part comprises a transmitting optical fiber (4) and a receiving optical fiber (5);

the light source (1), the lens (2) and the emitting optical fiber (4) are sequentially arranged along the light projection optical axis direction; the light source (1) is used for generating signal light (6), and the signal light (6) propagates along the light projecting optical axis direction after being emitted by the emitting optical fiber (4);

the receiving optical fiber (5) is an optical fiber beam combiner, and the detector (3) is arranged at the output end (51) of the optical fiber beam combiner; the input end (52) of the optical fiber combiner is used for receiving the signal light (6) emitted by the emitting optical fiber (4), and the signal light (6) enters the detector (3) after being transmitted by the optical fiber combiner.

2. The fiber optic sensor of claim 1, wherein the input end (52) of the fiber optic combiner is a fiber optic bundle of N fibers, N being greater than or equal to 2; the output end (51) of the optical fiber combiner is an optical fiber; the fiber bundle of the input end (52) has a flat light receiving surface.

3. The optical fiber sensor according to claim 2, characterized in that the output end (51) of the optical fiber combiner is perpendicular to the detection surface of the detector (3), and the cross-sectional area of the output end (51) of the optical fiber combiner is smaller than or equal to the area of the detection surface of the detector (3).

4. A fibre-optic sensor according to claim 3, characterized in that the detector (3) is selected from a photodiode, a position detector, a charge-coupled element or a complementary metal oxide semiconductor.

5. The fiber optic sensor of claim 2, wherein the optical fiber is a glass material or a polymer material.

6. The optical fiber sensor according to claim 2, wherein the emitting optical fiber (4) and the optical fiber combiner are respectively arranged at two sides of the detection station (7), and the emitting surface (42) of the emitting optical fiber (4) is coaxially arranged with the light receiving surface of the optical fiber combiner.

7. The fiber optic sensor according to claim 1, wherein the lens (2) is selected from one or more of a spherical mirror, an aspherical mirror, a parabolic mirror or a total internal reflection lens.

8. The fiber optic sensor according to claim 1, characterized in that the light source (1) is arranged on the optical axis of the lens (2), the light source (1) being selected from one or more of a light emitting diode, a laser diode or a vertical cavity surface emitting laser.

9. The fiber optic sensor according to claim 1, characterized in that the emitting fiber (4) and the fiber optic combiner are arranged at one side of a detection station (7), an input end (52) of the fiber optic combiner being adapted to receive the reflected signal light (6).