JP3343909B2 - Dew condensation detecting device and dew detecting method for optical fiber observation optical system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dew condensation detecting device and a dew detecting method for an optical fiber observation optical system for detecting the dew state of a light source or a camera in an optical fiber observation optical system for observing the state of an optical fiber.

[0002]

2. Description of the Related Art Conventionally, various devices having an optical fiber observation optical system for observing the state of an optical fiber have been put to practical use. The most common device having an optical fiber observation optical system is an optical fiber fusion splicer. The optical fiber observation optical system in the optical fiber fusion splicer illuminates each end of a pair of optical fibers facing each other with a light source, and takes an image of this with a camera. And, based on the image of the camera,
The ends of the pair of optical fibers are accurately positioned, and the state of fusion splicing is checked.

[0003]

The above-described optical fiber fusion splicer is used not only indoors but also in humid cavities or outdoors in rainy weather. For this reason, the optical fiber fusion splicer often moves from a place having a low temperature to a work place which is warm, and may cause dew condensation.
If dew condensation occurs in the optical fiber fusion splicer, it will be a hindrance to a desired operation, so that work may not be performed until the dew condensation is eliminated. In addition, if the operation is performed despite the occurrence of dew condensation, a fusion spliced state of unfavorable quality results.

[0004] Therefore, as an optical fiber fusion splicer for detecting such dew condensation, the one described in Japanese Patent Application Laid-Open No. H8-304659 is known. This fusion splicer has a moisture detection sensor, and particularly detects dew condensation in the vicinity of the electrode to always realize a stable discharge and to achieve preferable fusion splicing quality. However, this fusion splicer can detect the humidity atmosphere of the external environment, but cannot detect the dew condensation of the optical fiber observation optical system described above. Further, even if the presence or absence of dew condensation on portions other than the optical fiber observation optical system can be detected, it is impossible to estimate the degree of the dew condensation.

[0005] Unless the state of the optical fiber can be confirmed as an image during fusion splicing, it is very difficult to achieve favorable fusion splicing quality. Therefore, an object of the present invention relates to a dew condensation detecting device and a dew detecting method for an optical fiber observation optical system capable of detecting the dew condensation state of the optical fiber observation optical system.

[0006]

According to a first aspect of the present invention, there is provided a dew condensation detecting apparatus for an optical fiber observation optical system for detecting dew condensation in an optical fiber observation optical system for observing a state of an optical fiber, and illuminating the optical fiber. Light source, a camera that captures an optical fiber through the lens unit, and the brightness, luminous intensity, luminous flux, illuminance, or light of the light received by the camera when the light source is turned on .
Generated as a value representing light and dark in the electrical signal after photoelectric conversion
Based on the amount of light information of any of the generated luminance values ,
It is characterized by including a control unit for detecting the presence or absence of dew condensation of the light source or the lens unit and detecting the degree of dew condensation as a dew condensation state when dew is formed.

According to a second aspect of the present invention, in the dew condensation detecting device for an optical fiber observation optical system according to the first aspect, the relationship between the amount of light information of light received by the camera and the dew state of the light source or the lens unit is determined. It further includes a storage unit for storing as comparison data, and a display monitor connected to the control unit, wherein the control unit stores the optical information amount of light actually received by the camera when the light source is turned on and the storage unit. The dew condensation elimination time until the dew condensation of the light source or the lens portion is eliminated by comparing with the comparison data thus obtained is configured to be displayed on the display monitor. And

According to a third aspect of the present invention, there is provided a dew condensation detecting apparatus for an optical fiber observation optical system according to the first aspect, further comprising dew condensation eliminating means for eliminating dew condensation on a light source or a lens unit. When dew condensation is detected in the light source or the lens unit, dew condensation elimination means is controlled to forcibly eliminate the dew condensation in the light source or the lens unit.

A dew condensation detection method for an optical fiber observation optical system according to a fourth aspect is a dew condensation detection method for an optical fiber observation optical system for detecting dew condensation in an optical fiber observation optical system for observing a state of an optical fiber. Te, and at the same time illuminating the optical fiber by the light source, a lens unit to shoot the optical fiber by the camera having the bright light of the received light by the camera
Degree, luminous intensity, luminous flux, illuminance, or electrical signal after photoelectric conversion
Based on one of the light information amounts of the luminance values generated as the values representing the light and dark, the presence or absence of dew condensation of the light source or the lens unit and the degree of dew condensation are detected as the dew state. It is characterized by:

According to a fifth aspect of the present invention, there is provided a method for detecting dew condensation in an optical fiber observation optical system according to the fourth aspect of the present invention, wherein the amount of light information of light received by a camera, the amount of light information, and dew condensation
Based on a comparison with comparison data that stores a state relationship, the dew condensation elimination time until dew condensation of the light source or the lens unit is eliminated is estimated, and the estimated dew condensation elimination time is displayed on a display monitor. I have.

According to a sixth aspect of the present invention, in the method for detecting dew condensation of the optical fiber observation optical system according to the fourth aspect, the dew condensation on the light source or the lens unit is detected based on the amount of light information of the light received by the camera. When this is done, the dew condensation on the light source or the lens portion is forcibly eliminated.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a dew condensation detecting device and a dew detecting method for an optical fiber observation optical system according to the present invention will be described with reference to the drawings.

FIG. 1 shows a first embodiment of a dew condensation detecting device and a dew detecting method for an optical fiber observation optical system according to the present invention.
The optical fiber observation optical system in which dew is detected by the dew detection device of the present embodiment is configured as a part of a fusion splicer. As shown in FIG. 1, the fusion splicer has a pair of fixing bases 2a and 2b for fixing the pair of optical fibers 1a and 1b in a state of facing each other. A pair of fixed bases 2
a and 2b are slidable in the axial direction of the fixed optical fibers 1a and 1b. Further, the fusion splicer includes a pair of electrodes 3a, 3b for heating and melting the optical fibers 1a, 1b at a substantially intermediate position between the pair of fixing bases 2a, 2b.
have. The pair of electrodes 3a and 3b are arranged so as to be perpendicular to the axial direction of the fixed optical fibers 1a and 1b.

When the optical fibers 1a and 1b are fusion-spliced, a pair of fixed bases 2a and 2b are slid to each other so that each end of the pair of optical fibers 1a and 1b is connected to a pair of electrodes 3a and 3b. Struck between. This state is confirmed by an optical fiber observation optical system described in detail later. Next, electric discharge is performed between the pair of electrodes 3a and 3b to fuse the optical fibers 1a and 1b together. The states of the optical fibers 1a and 1b at the time of fusion and after fusion are also confirmed by an optical fiber observation optical system which will be described in detail later.

The optical fiber observation optical system and the accompanying dew condensation detection device will be described in detail.

The configurations of the optical fiber observation optical system and the dew condensation detecting device will be described. The optical fiber observation optical system has two light source-camera sets. As shown in FIG. 1, the light source 4a and the camera 5a constitute one set, and the light source 4b and the camera 5b constitute another set. In the present embodiment, LEDs are used as the light sources 4a and 4b. In addition, CCD cameras are used as the cameras 5a and 5b. CCD cameras 5a, 5b
Is used to transmit external light through the lens units 50a and 50b.
Take an image by receiving it at D.

In each set, a light source 4a and a camera 5a
Are arranged so that their optical axes are aligned, and similarly, the set composed of the light source 4b and the camera 5b are also arranged so that their optical axes are aligned. A set including the light source 4a and the camera 5a and the light source 4b
And a set including the camera 5b are arranged so as to be orthogonal to the X-shape. The intersection of both sets is arranged so as to intersect approximately between the pair of electrodes 3a and 3b described above. The light sources 4a, 4b and the cameras 5a, 5b are arranged on a plane substantially orthogonal to the axial direction of the pair of optical fibers 1a, 1b. By arranging the set including the light source 4a and the camera 5a and the set including the light source 4b and the camera 5b in this manner, the optical fiber 1
It is possible to observe three-dimensionally by observing the axial deviation of a and 1b and the cut angle of the end face from two directions.

The vicinity of each light source 4a, 4b and the camera 5
Heaters 6a to 6d are provided in the vicinity of the lens portions 50a and 50b, a and 5b, respectively. The heaters 6a to 6d generate heat when energized, and
a, 4b or functions as dew condensation eliminating means for forcibly eliminating the dew condensation generated in the lens units 50a, 50b.

The above-mentioned light sources 4a, 4b and cameras 5a, 5
b and the heaters 6a to 6d are connected to the control unit 7, respectively. The control unit 7 includes a CPU that performs arithmetic processing, a storage unit 7a such as a RAM that stores various data, and an I / O unit that exchanges data with the outside. The control unit 7 controls the brightness of the light sources 4a and 4b and controls the cameras 5a and 5b through the lens units 50a and 50b.
An image is generated from the image data captured in b. Control unit 7
Is also connected to a display monitor 8, and the generated image is displayed on the display monitor 8.

The control section 7 also controls on / off of the heaters 6a to 6d. Further, the storage unit 7a of the control unit 7 stores various information (such as a threshold value for dew condensation determination described later) for determining the dew condensation state of the light sources 4a and 4b and the lens units 50a and 50b.

Further, when the light sources 4a, 4b are turned on, the control unit 7 controls the cameras 5a, 5b through the lens units 50a, 50b.
Based on the amount of light information of the light received by b, the dew condensation state (whether or not there is dew condensation and how much dew is formed, if any) on the light sources 4a and 4b or the lens units 50a and 50b is also detected. The amount of light information referred to here is luminance (cd / m ² as an example of a unit), luminous intensity (cd as an example of a unit), luminous flux (lm = cd · sr as an example of a unit) or illuminance. (Example of the unit is lx = lm / m ² ). In the present embodiment, a luminance value described below is used as an optical information amount for detecting the dew condensation state.

Each of the cameras 5a and 5b has a CCD inside, and performs photoelectric conversion by the CCD and outputs an image as an electric signal. Among these electric signals, a signal relating to the brightness of an image is output as a luminance signal. In this embodiment, the luminance signal is evaluated in 256 levels, and the level of the received light is output as a luminance signal. Here, a luminance signal at a predetermined point on the CCD when light is received at a predetermined sensitivity level is used as a luminance value to determine the dew condensation state. That is, the value of the brightness value takes a value from 0 to 255, and the closer to 0, the darker the brightness becomes.
The closer to 5, the brighter. In the present embodiment, the dew condensation state is detected based on the above-described luminance value. The detected dew condensation state is displayed on the display monitor 8.

The operation of detecting the state of dew condensation by the dew detection device of the optical fiber observation optical system will be described. FIG.
The flowchart of this operation is shown in FIG. When using the above fusion splicer, the dew condensation state of the optical fiber observation optical system is checked. First, the light sources 4a and 4b are turned on and LE
D irradiation is performed (step 100). Here, the light source 4
a and 4b are turned on at a preset brightness. Next, the above-mentioned luminance value is measured by the cameras 5a and 5b (step 110).

After the luminance value is measured, the measured luminance value is compared with a threshold value for dew condensation determination stored in the storage unit 7a of the control unit 7 in advance (step 120). If the measured luminance value is lower than the luminance threshold value, it is determined that condensation has occurred, and a message to that effect (message display (1)) is displayed on the display monitor 8 to indicate that the condensation elimination operation is being performed. Is also displayed (step 130).

The reason why the dew condensation has occurred when the measured luminance value is lower than the luminance value threshold value is as follows. When dew condensation occurs on the light sources 4a and 4b, the light sources 4a and 4b
The light emitted from the light source 4b is diffused and reflected by dew condensation at the time when the light is emitted from the light sources 4a and 4b, so that the measured luminance value decreases. Similarly, the lens units 50a, 50b
When dew condensation occurs, the light emitted from the light sources 4a and 4b is diffused and condensed by the dew condensation on the surfaces of the lens units 50a and 50b.
Again, because of the reflection, the measured luminance value is reduced.
Therefore, when the measured luminance value is lower than the luminance value threshold value, it can be determined that dew condensation has occurred.

In the present embodiment, following step 130, the heaters 6a to 6d are used as a dew condensation eliminating operation.
The dew condensation that has occurred is forcibly eliminated (step 14).
0). In this dew condensation elimination operation, the heaters 6a to 6d are energized for a predetermined time and the light sources 4a and 4b or the lens units 50a and 50d are energized.
The condensation occurring in b is eliminated. The above-mentioned predetermined time may be fixed to a fixed time, or may be variably controlled based on the measured luminance value. Heaters 6a-6
When variably controlling the time for energizing d, the relationship between the measured luminance value and the energizing time to the heaters 6a to 6d is stored in a storage unit 7a of the control unit 7 as a map (or an arithmetic expression), and based on this. What is necessary is just to determine the energizing time to the heaters 6a to 6d.

When step 140 is completed, steps 110 and 120 are performed again, and it is confirmed from the measured luminance value that the condensation has been eliminated. On the other hand, step 120
In the case where the measured luminance value is equal to or greater than the luminance threshold value,
Since it can be determined that no condensation has occurred, a message indicating that there is no condensation and fusion splicing can be performed [message display (2)] is displayed on the display monitor 8 (step 150).

Note that the above-described dew condensation detection operation is performed by the light source 4
a and 4b and the cameras 5a and 5b may be performed simultaneously or one set at a time. When the luminance value is measured again in step 110 after performing steps 130 and 140, if it can be determined from the measured luminance value that the dew condensation state has not been improved, it is determined that an abnormality has occurred. The display can be displayed on the display monitor 8.

Next, a description will be given of a second embodiment of the dew condensation detecting device of the optical fiber observation optical system according to the present invention. FIG. 3 shows the optical fiber observation optical system and the dew condensation detecting device of the present embodiment. Since the optical fiber observation optical system and the dew condensation detecting device of the present embodiment have substantially the same configuration as that of the above-described first embodiment, a portion different from the first embodiment will be described in detail below. The same parts as those in the embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

In the dew condensation detecting device of this embodiment, fans 9a to 9d are provided as dew elimination means instead of the heaters 6a to 6d of the first embodiment. And light source 4
In the case where dew condensation has occurred on the light source 4a, 4b or the lens portions 50a, 50b, the surrounding gas (usually air) is emitted by the fans 9a to 9d.
Dew condensation is eliminated by spraying on 50b. The control method of the dew condensation detecting device according to the present embodiment is the same as the control method according to the above-described first embodiment, and a detailed description thereof will be omitted.

Here, the power supply unit 1 of the dew condensation detecting device is used.
0 (the power supply of the optical fiber observation optical system or the power supply of the fusion splicer).
9d, the light sources 4a, 4b or the lens portions 50a, 50
b. For this reason, the light sources 4a and 4b or the lens portions 50a and 50b can be eliminated earlier and more reliably.

Next, a description will be given of a third embodiment of the dew condensation detecting device of the optical fiber observation optical system according to the present invention. FIG. 4 shows the optical fiber observation optical system and the dew condensation detecting device of the present embodiment. Since the optical fiber observation optical system and the dew condensation detection device of the present embodiment also have substantially the same configuration as that of the above-described first embodiment, the following will describe in detail parts different from the first embodiment. The same parts as those in the embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

The dew condensation detecting device of this embodiment does not have a configuration corresponding to the heaters 6a to 6d of the first embodiment. The dew condensation elimination operation in step 140 in the flowchart shown in FIG. 2 differs accordingly. In step 140 in the present embodiment, first, the measured luminance value is compared with comparison data (see the table shown in FIG. 5) stored in advance in the storage unit 7a, and the estimated time until the dew condensation is eliminated is determined. It is set and then stands by until the time when the condensation is eliminated elapses. At this time, the estimated time until the dew is eliminated is displayed on the display monitor 8.

Alternatively, instead of the determination in step 120 of the flowchart shown in FIG. 2, the measured luminance value is compared with the comparison data. May shift to step 150. In this case, the condensation elimination operation in step 140 waits for the condensation elimination time estimated in step 120.

In this embodiment, the dew condensation is eliminated when the estimated dew condensation elimination time elapses. Condensation is naturally resolved if the temperatures of the light sources 4a and 4b and the lens units 50a and 50b are adjusted to the surrounding temperature, and the decompression is promoted by the heat generated by the light sources 4a and 4b and the power supply unit 10. For this reason, as in the first embodiment and the second embodiment, dew condensation can be eliminated without forcibly eliminating the dew condensation using means such as the heaters 6a to 6d and the fans 9a to 9d. For example, a portable fusion splicer or the like has a limited amount of battery power. Therefore, as a dew condensation detecting device for an optical fiber observation optical system in such a fusion splicer, the dew condensation It is also useful to suppress power consumption without driving the means.

The above-mentioned comparison data is obtained in advance by performing an experiment or the like, and is recorded in the storage unit 7a. It is preferable that the estimated time displayed on the display monitor 8 be counted down as time elapses, so that the operator can grasp the state. Other points are the same as those of the first embodiment described above.

The present invention is not limited to the above embodiment. For example, in the embodiment described above,
Although the situation of a pair of single-core optical fibers has been observed, it is also possible to observe a plurality of optical fibers in a tape-shaped optical fiber core. Further, the above-described dew condensation detecting device of the optical fiber observation optical system is configured as a part of the fusion splicing device. Of course, it may be configured as a part of the fusion splicer in this way, but it is not limited to being configured as a part of the fusion splicer as long as it observes the state of the optical fiber. .

In the above-described optical fiber observation optical system, two sets of a light source and a camera are provided, but the present invention can be applied to only one set. Alternatively, the above-described light sources 4a and 4b may be integrated into one, and the cameras 5a and 5b may be integrated into one. Also,
Although the display monitor 8 of the above-described embodiment displays both an image and a message, the image monitor and the message monitor may be provided separately. Monitors for message display include LCD dial, CRT, LE
Any lighting of D may be used.

The above-described heaters 6a to 6d and fans 9a to 9d can be used in combination. Note that, as a matter of course, the above-described heaters 6a to 6d or the fans 9a to 9d are arranged at positions where the photographing by the cameras 5a and 5b is not hindered. Or heater 6
a to 6d or the fans 9a to 9d may be movable, and may be retracted to a position where the shooting is not hindered during shooting by the cameras 5a and 5b.

[0040]

According to the first aspect of the present invention, the light irradiated by the light source is received by the camera, and the dew condensation is detected based on the amount of light information of the light received by the camera. It is possible to reliably detect the dew condensation on the part.
Further, not only the presence or absence of dew but also the degree of dew can be detected from the information amount of light.

According to the second aspect of the present invention, the dew condensation elimination time until the dew condensation is eliminated is estimated by comparing the dew condensation elimination time with the comparison data stored in the storage unit. It can be displayed on a display monitor.
For this reason, the dew condensation state of the optical fiber observation optical system can be reliably transmitted to the operator, and work using the optical fiber observation optical system can be performed more efficiently.

According to the third aspect of the invention, when it is detected that dew has formed, the dew can be forcibly eliminated by the dew condensation eliminating means, and the optical fiber observation optical system can be used. Work can be performed more efficiently.

According to the fourth aspect of the present invention, the light irradiated by the light source is received by the camera, and the dew condensation is detected based on the amount of light information of the light received by the camera. It is possible to reliably detect the dew condensation on the part. Further, not only the presence or absence of dew but also the degree of dew can be detected from the information amount of light.

According to the fifth aspect of the present invention, the dew condensation elimination time until the dew condensation is eliminated is estimated from the optical information amount of light received by the camera, and the estimated dew condensation elimination time is displayed on the display monitor. be able to. For this reason, the dew condensation state of the optical fiber observation optical system can be reliably transmitted to the operator, and work using the optical fiber observation optical system can be performed more efficiently.

According to the sixth aspect of the present invention, when it is detected that dew condensation has occurred, the dew condensation can be forcibly eliminated by the dew condensation eliminating means, and the optical fiber observation optical system can be used. Work can be performed more efficiently.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a first embodiment of a dew condensation detecting device of an optical fiber observation optical system of the present invention.

FIG. 2 is a flowchart of a method for detecting dew condensation in the optical fiber observation optical system according to the present invention.

FIG. 3 is a configuration diagram showing a second embodiment of the dew condensation detecting device of the optical fiber observation optical system of the present invention.

FIG. 4 is a configuration diagram showing a third embodiment of the dew condensation detecting device of the optical fiber observation optical system of the present invention.

FIG. 5 is a table of comparison data used in the apparatus shown in FIG. 4;

[Explanation of symbols]

1a, 1b: optical fiber, 4a, 4b: light source, 5a, 5
b: camera, 6a to 6d: heater (condensation eliminating means),
7: control unit, 7a: storage unit, 8: display monitor, 9a to
9d: fan (condensation eliminating means), 10: power supply unit.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2000-81532 (JP, A) JP-A-60-212416 (JP, A) JP-A-3-241328 (JP, A) JP-A-2-24649 (JP, A) Jikkai Hei 6-34372 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) G02B 6/255

Claims (6)

(57) [Claims] 1. A dew condensation detecting device for an optical fiber observation optical system for detecting dew condensation of an optical fiber observation optical system for observing a state of an optical fiber, comprising: a light source for illuminating the optical fiber; a camera for photographing, bright of the light received by the camera at the time of lighting of the light source
Degree, luminous intensity, luminous flux, illuminance, or electrical signal after photoelectric conversion
Based on any light information amount of the luminance value generated as a value representing light and dark in the presence or absence of dew condensation of the light source or the lens unit and the degree of dew condensation as a dew state A dew detection device for an optical fiber observation optical system, comprising: a control unit for detecting. 2. A storage unit for storing, as comparison data, a relationship between an optical information amount of light received by the camera and a dew state of the light source or the lens unit, and a display monitor connected to the control unit. The control unit compares the light information amount of light actually received by the camera when the light source is turned on with the comparison data stored in the storage unit, and the light source or the lens. 2. The dew condensation detection of the optical fiber observation optical system according to claim 1, wherein dew condensation elimination time until the dew condensation on the unit is eliminated is configured to be displayed on the display monitor. apparatus. 3. The apparatus according to claim 2, further comprising a dew condensation eliminating unit configured to eliminate dew condensation on the light source or the lens unit, wherein the control unit detects that dew condensation on the light source or the lens unit occurs. The dew condensation detecting device for an optical fiber observation optical system according to claim 1, wherein dew condensation is controlled by controlling dew condensation eliminating means. 4. A dew condensation detecting method for an optical fiber observation optical system for detecting dew condensation in an optical fiber observation optical system for observing a state of an optical fiber, the camera having a lens unit while illuminating the optical fiber with a light source. The optical fiber is photographed by the light of the light received by the camera ,
Brightness or darkness in bundle, illuminance, or electrical signal after photoelectric conversion
The presence or absence of dew condensation of the light source or the lens unit and the degree of dew condensation are detected as a dew state based on one of the light information amounts of the luminance values generated as values representing A method for detecting dew condensation in an optical fiber observation optical system, characterized in that: 5. A comparison data storing an amount of light information of light received by the camera and a relation between the amount of light information and a dew state.
5. The optical fiber according to claim 4, wherein a dew condensation elimination time until the dew condensation of the light source or the lens unit is eliminated is estimated based on a comparison with the data, and the estimated dew condensation elimination time is displayed on a display monitor. Dew condensation detection method for the observation optical system. 6. When the dew condensation on the light source or the lens unit is detected based on the optical information amount of light received by the camera, the dew condensation on the light source or the lens unit is forcibly eliminated. 5. The method for detecting dew condensation of the optical fiber observation optical system according to 4.