CN110132136A - A kind of digital optical fiber length measuring system of XOR logic - Google Patents
A kind of digital optical fiber length measuring system of XOR logic Download PDFInfo
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- CN110132136A CN110132136A CN201910369062.2A CN201910369062A CN110132136A CN 110132136 A CN110132136 A CN 110132136A CN 201910369062 A CN201910369062 A CN 201910369062A CN 110132136 A CN110132136 A CN 110132136A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
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Abstract
The invention belongs to optical fiber length measuring equipment technical fields, disclose a kind of digital optical fiber length measuring system of XOR logic.It is provided with clock signal；Clock signal electro-optic conversion；Tested optical fiber；Clock signal photoelectric conversion and regeneration；XOR logic fiber lengths sensor；Double-bevel analog-digital converter；Oscillograph.Clock signal is 50% square wave electrical signal of duty ratio, is converted into square wave optical signal through electro-optical conversion circuit；After optical signal is transferred to the other end by tested optical fiber, is adjusted by photoelectric conversion and regeneration and be converted into 50% square wave electrical signal of duty ratio.Reference signal in clock signal electro-optical conversion circuit is connected to an input terminal of the channel oscillograph CH1 and fiber lengths sensor；Regenerated signal is connected to the channel CH2 and fiber lengths sensor another input terminal of oscillograph.XOR logic fiber lengths sensor output is connected to double-bevel analog to digital conversion circuit.After calibration, above structure is exactly a digital optical fiber length measuring instrument.
Description
Technical field
The invention belongs to digital optical fiber length measuring equipment technical field more particularly to a kind of digital light of XOR logic
Fine length measuring system.
Background technique
Currently, the method for measuring fiber lengths in optical fiber engineering often uses time-domain reflectomer, this method is in optical fiber
The light velocity is based on 200,000 kilometer per seconds, the turnaround time calculates fiber lengths in a fiber according to light pulse.It is of the present invention different
Or the digital optical fiber length measuring instrument of logic, be a kind of physical concept is completely new, measurement method is ingenious, intuitive measurement results it is novel
Optical fiber length measuring instrument.Its basic principle is not that the light velocity is 200,000 kilometer per seconds as physical basis using in optical fiber.It is actually
It is a fiber lengths comparator.It is to be turned using XOR circuit as fiber lengths sensor, using double-bevel modulus
It changes the simulation trial function of circuit and realizes light using full-length intelligent acess measuring system and by technologies such as calibration adjustings
The novel optical fiber length measuring instrument of fine length digitized measurement.It is essential in light velocity measurement teaching experiment in a fiber
Instrument cannot be anti-using time domain because the light velocity in optical fiber is itself is a physical quantity to be measured in this experiment
Instrument is penetrated as optical fiber length measuring instrument.Certainly, the digital optical fiber length measuring instrument of XOR logic of the present invention also can be used
In other technical fields of fiber manufacturing industry.
The digital optical fiber length measuring instrument of XOR logic of the present invention, in order to realize the digitized measurement of fiber lengths
It needs to carry out using DC level of the double-bevel analog-digital converter to the square wave sequence that XOR logic fiber lengths sensor exports
Measurement.Under normal conditions, double-bevel analog-digital converter is for measuring DC voltage.It is long with optical fiber can be used to accurate measurement
Spend the DC level of the square wave sequence of related XOR logic fiber lengths sensor output? it also needs to carry out theory analysis.This hair
The bright feasibility for theoretically demonstrating this application, obtains strong theories integration.Technically, double-bevel modulus is utilized
The simulation trial function of converter solves the zeroing and calibration problem of the digital optical fiber length measuring instrument of XOR logic.
Summary of the invention
In view of the problems of the existing technology, the present invention provides a kind of digital optical fiber length measuring systems of XOR logic
System.This digital optical fiber length measuring instrument of XOR logic is provided with
Clock signal；Clock signal electro-optical conversion circuit；Tested optical fiber；Clock signal photoelectric conversion and regeneration adjust electricity
Road；XOR logic fiber lengths sensor；Double-bevel analog-digital converter；Oscillograph.
The square-wave signal that signal source of clock --- duty ratio is 50%, the period can be appropriate according to the range of fiber lengths instrument
Selection.16 μ S or 32 μ S are now chosen to be, are selected by switching.
The connection of signal source of clock and clock signal electro-optical conversion circuit --- if attached drawing 2 shows, signal source of clock output is connect
The base stage of transistor BG1 into clock signal electro-optical conversion circuit；Light source device LD connects the collector in transistor BG1
In circuit；LD light power regulating device is the potentiometer W1 in transistor BG1 emitter circuit；Transistor BG1
Emitter is connect with the input pin of inverter ic 1, the signal drawn from 1 output pin of inverter ic, as reference signal；
The connection of tested optical fiber and light source device LD and photoelectricity testing part PIN --- pass through optical fiber tie jumper and optical fiber
Flexible jumper is connect with LD and PIN；
Clock signal photoelectric conversion and regeneration adjust circuit --- and if attached drawing 3 shows, use response wave length scope for 900-
The PIN photodiode of 1700nm makees photoelectricity testing part, is connected to clock signal photoelectric conversion and regeneration adjusts three poles in circuit
Between the base stage and GND of pipe BG2；Below-center offset resistance after potentiometer W2 connects with resistance Rb1, as transistor BG2；It adjusts
The saturation depth of BG2 can be changed in nodal potential device W2, in the case where being incident on the certain situation of PIN photodiode photosurface optical power, adjusts
Nodal potential device W2 can also realize that the regeneration of clock signal is adjusted.Clock signal photoelectric conversion and regeneration adjust three pole of crystal in circuit
The collector of pipe BG2 is connect with the non-inverting input terminal of open-loop voltage amplifier K, the output end and inverter ic 2 of voltage amplifier K
Input connection, the output end of inverter ic 2 is as regenerated signal output end.
Fiber lengths sensor and double-bevel analog to digital conversion circuit --- if attached drawing 7 shows, using XOR circuit as
Fiber lengths sensor, its two input terminals one connect reference signal output, another connects regenerated signal output end.Exclusive or
Logic circuit output end is followed by 31 ends foot Vin+ of 7107 analog-digital converter of double-bevel through dividing.7107 double-bevel analog-digital converters
30 foot Vin- termination zero point adjust the movable end of potentiometer W1,7,107 36 foot R ref+ termination calibration adjusts potentiometer W2
Movable end.Utilize the simulation trial function reality digitized measurement of fiber lengths of 7107 double-bevel analog to digital conversion circuits；
Light power meter --- for monitoring optical signal magnitude, calibration wavelength is 1310nm, and range is 0-2000 μ W；It with
Clock signal photoelectric conversion and regeneration adjust circuit and share same PIN photodiode；It can be PIN light by switching switch K
Electric diode is respectively connected to light power meter or clock signal photoelectric conversion and regeneration is adjusted in circuit.
In conclusion the present invention is a kind of novel optical fiber length measuring system and method, with existing time-domain reflectomer ratio
Compared with measurement result is more intuitive.Particularly suitable for light velocity measurement, fibre loss characteristic test in optical fiber related in fibre optics etc.
In teaching experiment.Due to using powerful light source device and efficient electrooptical device, entire measuring system measurement
Data stabilization, measurement number are accurate, and the error of measurement result is within the scope of 0.5%-1.0%.XOR logic of the present invention
Digital optical fiber length measuring instrument, in order to realize that the digitized measurement of fiber lengths is needed using double-bevel analog-digital converter to different
Or the DC level of the square wave sequence of logic fiber lengths sensor output measures.Under normal conditions, double-bevel modulus turns
Parallel operation is for measuring DC voltage.It can be used to accurate measurement XOR logic fiber lengths sensing related with fiber lengths
The DC level of the square wave sequence of device output? it also needs to carry out theory analysis.What the present invention theoretically demonstrated this application can
Row obtains strong theories integration.Technically, it is solved using the simulation trial function of double-bevel analog-digital converter different
Or the zeroing and calibration problem of the digital optical fiber length measuring instrument of logic.Certainly, the digital light of XOR logic of the present invention
Fine length measuring instrument can also be used for other technical fields of fiber manufacturing industry.
The digital optical fiber length measuring instrument of XOR logic of the present invention is that a kind of physical concept is completely new, measurement method
Ingenious, intuitive measurement results novel optical fiber linear measure longimetry instrument.Its basic principle be not with the light velocity in optical fiber be 200,000 kilometers/
Second is used as physical basis.It is actually a fiber lengths comparator.It is sensed using XOR circuit as fiber lengths
Device, using double-bevel analog to digital conversion circuit simulation trial function and utilize full-length intelligent acess measuring system and by school
Standard realizes the digitized measurement of fiber lengths after adjusting.It is essential instrument in light velocity measurement teaching experiment in a fiber
Device cannot apply time-domain reflectomer because itself is a physical quantitys to be measured for the light velocity in optical fiber in this experiment
As optical fiber length measuring instrument.
Detailed description of the invention
Fig. 1 is the digital optical fiber length measuring system structure diagram of XOR logic provided in an embodiment of the present invention.
Fig. 2 is the electro-optical conversion circuit schematic diagram of clock signal provided in an embodiment of the present invention.
Fig. 3 is that the photoelectric conversion of clock signal provided in an embodiment of the present invention and regeneration adjust circuit diagram.
Fig. 4 is XOR logic fiber lengths Fundamentals of Sensors figure provided in an embodiment of the present invention.
Fig. 5 is fiber lengths sensor senses characteristic schematic diagram provided in an embodiment of the present invention.
Fig. 6 is the operation principle schematic diagram that double-bevel provided in an embodiment of the present invention touches several conversion circuits.
Fig. 7 is the electrical block diagram of the digital optical fiber length measuring instrument of XOR logic provided in an embodiment of the present invention.
Fig. 8 is that XOR circuit is defeated when fiber lengths provided in an embodiment of the present invention are equal to zero and are equal to half range length
Waveform diagram out.
In figure: 1, signal source of clock；2, clock signal electro-optical conversion circuit；3, tested optical fiber；4, clock signal photoelectricity turns
It changes and regenerates and adjust circuit；5, XOR logic fiber lengths sensor；6, double-bevel analog-digital converter；7, digital oscilloscope.
Specific embodiment
In order to make the objectives, technical solutions, and advantages of the present invention clearer, with reference to embodiments, to the present invention
It is further elaborated.It should be appreciated that the specific embodiments described herein are merely illustrative of the present invention, it is not used to
Limit the present invention.
The working principle of the invention is explained in detail with reference to the accompanying drawing.
As shown in Figure 1, the digital optical fiber length measuring system of XOR logic provided in an embodiment of the present invention includes: clock letter
Number source 1, clock signal electro-optical conversion circuit 2, tested optical fiber 3, the photoelectric conversion of clock signal and regeneration adjust circuit 4, optical fiber
Pass linear transducer 5, double-bevel analog-digital converter 6, digital oscilloscope 7.
Signal source of clock 1 is connect by square wave electrical signal with clock signal electro-optical conversion circuit 2, clock signal electro-optic conversion
Circuit 2 is connect by optical signal with tested optical fiber 3, and tested optical fiber 3 is adjusted by optical signal and clock signal photoelectric conversion and regeneration
Economize on electricity road 4 connects, and clock signal photoelectric conversion and regeneration adjust circuit 4 and passes linear transducer 5 by regenerated signal and optical fiber
One input terminal connection, another input terminal and the reference in clock signal electro-optical conversion circuit 2 that optical fiber passes linear transducer 5
The output end of signal output end connection, fiber lengths sensor 5 is connect by DC level with double-bevel analog-digital converter 6.
The reference signal output of clock signal electro-optical conversion circuit 2 is connected to the channel CH1 of digital oscilloscope 7；Clock letter
Number photoelectric conversion and regeneration adjust the regenerated signal output in circuit 4 and be connected to the channel CH2 of digital oscilloscope 7.
The circuit structure of the digital optical fiber length measuring instrument of XOR logic are as follows: if attached drawing 7 shows, optical fiber passes linear transducer 5
Output end after dividing with No. 31 pin V in 7107 integrated chipsin-Connection；COM pin in 7107 integrated chips with
Digitally connect；Potentiometer W1 connects with resistance R1 and is followed by between+5V and GND, and the movable end of potentiometer W1 and 7107 integrates
No. 30 pin V in chipin-Connection；Potentiometer W2 and resistance R2 series resistance also connect between+5V and GND, potentiometer W2
Movable end and 7107 integrated chips in No. 36 pin Vref+Connection.
The working principle of the invention is further described below with reference to specific embodiment.
Embodiment 1
The signal source of clock output of measuring system is square wave that duty ratio is %50, and the period can be delicate and 16 is delicate 32
Between switch.
Embodiment 2
The electro-optical conversion circuit of clock signal such as Fig. 2 shows that signal source of clock exports the base stage for being connected to transistor BG1；Light source
Device LD connects in the collector circuit of transistor BG1；LD light power regulating device is transistor BG1 emitter
Potentiometer W1 in circuit；Transistor BG1 emitter is connect with the input pin of inverter ic 1, from 1 output pin of inverter ic
The signal of extraction, as reference signal；Optical signal is drawn from LD using optical fiber tie jumper.Due to using LD, optical signal can be made
Amplitude is sufficiently large, and the photoelectric conversion and regeneration for adapting to subsequent clock signal adjust circuit needs.
Embodiment 3
The photoelectric conversion of clock signal adjusts circuit such as Fig. 3 with regeneration and shows, the optical signal of tested optical fiber output passes through optical fiber
Wire jumper is irradiated on the photosurface of PIN photodiode, and PIN is connected between the base stage and GND of transistor BG2；Potentiometer
Below-center offset resistance after W2 connects with resistance Rb1, as transistor BG2；Adjusting potentiometer W2 can be changed the saturation depth of BG2
Degree, in the case where being incident on the certain situation of PIN photodiode photosurface optical power, clock signal can also be realized by adjusting potentiometer W2
Regeneration is adjusted.The collector of transistor BG2 is connect with the non-inverting input terminal of open-loop voltage amplifier K, voltage amplifier K's
Output end is connect with the input of inverter ic 2, and the output end of inverter ic 2 is as regenerated signal output end.Due to measuring system
In use LD light source device and PIN photoelectric device, greatly strengthen the stability of reproduction waveform, the clock cycle 16 can when delicate
Make the jitter range of the positive pulsewidth of reproduction waveform between positive and negative 10nS.
Embodiment 4
XOR logic fiber lengths sensor such as attached drawing 4 shows, the reference signal output end and reception that the transmitting terminal period is T
The regenerated signal output at end is when terminating to two input terminals of XOR circuit, and output waveform is exactly that a cycle is T/2, but
The pulsewidth square wave sequence directly proportional to its relative time delay τ of two input signals.When two-way input signal delay τ is in 0-T/2
In the range of when, the direct current level values V of this square wave sequenceOIn VLWith VhJust there is following proportional relation with τ in range:
V0=VL+[2(Vh-VL)τ/T]
V in above formulaLThe low level value that XOR gate exports when being two-way input signal same-phase, VhIt is two-way input signal
The high value that XOR gate exports when antiphase.So XOR circuit is in the application that attached drawing 4 shows, it is exactly a kind of delay
Sensor.Due in the relative time delay of XOR circuit two-way input signal, including circuit delay and optical path are delayed two parts,
Wherein optical path delay is directly proportional to the length of fiber channel.Measuring system will not be made always to be delayed in fiber lengths is more than the model of T/2
In enclosing, above formula can also be changed to:
Vo=a+K*L
So the above-mentioned usage of XOR circuit and a fiber lengths sensor, sensing characteristics such as figure attached drawing 5
Show.Wherein intercept a (dimension: volt), it is related with the cycle T of the circuit delay of measuring system, modulated signal；Slope K (dimension: volt/
Rice) with optical fiber in the light velocity, the cycle T of modulated signal and the low and high level V of XOR circuith、VLIt is related.Due in optical fiber
The light velocity, XOR circuit low and high level Vh、VLCentainly, it is possible to which the factor for changing slope K only has the week of modulated signal
Phase T.
Embodiment 5
In order to realize the digitized measurement of fiber lengths, need to connect a double-bevel mould behind optical fiber biography linear transducer
Number conversion circuit.Under normal conditions, double-bevel analog-digital converter is for measuring DC voltage.Can be used to accurate measurement with
The DC level of the square wave sequence of the related XOR logic fiber lengths sensor output of fiber lengths?, also need to carry out theoretical point
Analysis.The core of double-bevel analog to digital conversion circuit is the integrating circuit shown such as attached drawing 6, and analog-digital conversion process was divided into for three stages:
First stage is closed related analog switch by control circuit, and bleed off makes integrating condenser due to various reasons
CintThe electricity accumulated on two-plate, this stage are known as automatic clear stage
Second stage, timing sampling stage, in this stage control circuitorder analog switch K by XOR circuit output end
It is connected with the Vi+ of integrating circuit, integrating condenser CintIt starts to charge.From different, charging current V/ the case where measurement DC voltage
RintIt is inconstant, it changes over time.Its changing rule and XOR circuit output voltage change over time rule one
Sample.Therefore, the output voltage V of integrating circuitintIt in entire sample phase is increased at any time by the straight line of same slope
Add.During positive pulsewidth, VintIt is fast increase with time, increase during negative pulsewidth very slow.It is double while switch K connects the end Vi+
Start inside inclined analog to digital conversion circuit to clock pulse count, when counting down to a certain determining value (1000) N1, control circuit
Sampling process is enabled to terminate.Therefore sample time T1 is fixed.The voltage at integrating capacitor both ends, Ye Jiji at the end of sample phase
The output voltage V of parallel circuitIntIt can be by following Definite Integral Calculation:
(1) negative sign of formula right side of the equal sign shows VintThere is opposite polarity with V (t).This is because: if V (t) is
Just, then capacitor C in Fig. 6intRight pole plate is negatively charged, therefore VintPolarity is negative, conversely, VintIt is positive.
It is the DC level and condition proved double-bevel analog-digital converter and can be used to measure square wave sequence below:
If sample time T1 is XOR circuit output square wave sequence V (t) cycle TyN integral multiple, formula (1) can
It rewrites are as follows:
In above formulaIt is exactly the DC level of XOR circuit output square wave sequence V (t).
Under normal circumstances, sample time T1 is not XOR circuit output square wave sequence V (t) cycle TyIntegral multiple.
If T1 is divided by TyQuotient be n, then remainder T1-nTy.In the case, integrating circuit output voltage V at the end of sample phaseint
It should be expressed from the next:
In XOR logic fiber lengths digitized measurement system, TyIt is the delicate order of magnitude, double-bevel analog to digital conversion circuit
Sample time T1 be the several ms order of magnitude.So T1 is very big divided by the quotient n of Ty, have 103The order of magnitude and remainder T1-
nTyThe very little very little compared with T1.So formula (3) can approximation write as formula (2) same form, it may be assumed that
Compared with the error of the other links of measuring system, this approximation can neglect influence brought by accuracy of measurement completely
Slightly.
The double-bevel analog-to-digital conversion phase III is known as measuring phases.In second stage finish time, analog switch K immediately
Integrating circuit is connected to and the opposite polarity reference voltage V of V (t)ref.Capacitor CintStart with constant current Vref/R intIt puts
Electricity, at the same time, counter start counting.Integrating circuit output voltage starts linearly to reduce, as capacitor CintOn electricity
It when pressure drop most zero, gives control circuit one signal by zero comparator, enables counter stop counting, so measuring phases are passed through
The time T2 gone through should meet following relationship:
Wherein T1, VrefBe constant in measurement process, thus T2 withIt is directly proportional.If double-bevel analog-digital converter
The counting pulse period is Tcp, T1=N1Tcp, T2=N2Tcp, then (5) formula can be rewritten as:
This shows: measuring phases count value N2 withIt is directly proportional.In 3 half analog-digital converters, N1 is fixed as
1000, N2 count range is 1~2000.In common DC voltage measurement technology, VrefIt is configured to 100mV, or
1.0V.And in digital XOR logic optical fiber length measuring technology, it is special according to the sensing of XOR logic fiber lengths sensor
Property, the connection between sensor and double-bevel analog-digital converter is to reference voltage VrefIt can have different selections.Due to exclusive or
Logic fibre optical sensor sensing characteristics not zero crossing, needs the V in double-bevel analog-digital converterin-One its value of termination and sensing
The equal benefit of characteristic intercept appreciates voltage.In 3 Semi-digital instrument, the range of optical fiber length measuring instrument is 0-2000 in number
(temporarily regardless of unit).When the length of tested optical fiber is in number 1000, if it is desired to the reading N2 of optical fiber length measuring instrument
It is also 1000, according to formula (5 '), the reference voltage V of double-bevel analog to digital conversion circuitrefJust should be equal to fiber lengths be 1000 when
Corresponding DC level V on fiber lengths sensor senses characteristic straight lineOWith the difference of sensing characteristics intercept a.
Embodiment 6
The circuit structure and parameter of the digital optical fiber length measuring instrument of XOR logic calculate
The circuit structure such as attached drawing 7 of the digital optical fiber length measuring instrument of XOR logic shows.Analog to digital conversion circuit uses 7107
Integrated chip.From different, the V of 7107 chips the case where being used for usual DC voltage measurementin-End is directly coupled to the end COM
Together, but it is connected to benefit reward voltage Vb, adjusting W1 can be changed VbSize reaches optical fiber length measuring instrument zero point and adjusts purpose.It adjusts
Saving W2 can be changed the reference voltage V of analog to digital conversion circuitrefSize reaches optical fiber length measuring instrument range calibration purpose.
Mend reward voltage VbWith reference voltage VrefTheoretical value and Fig. 5 show the sensing characteristics curve of fiber lengths sensor
Intercept a it is related with slope K.When designing digital XOR logic optical fiber length measuring instrument, need to know their exact value.?
Theoretically, steps are as follows for calculating:
Step 1 determines the range of optical fiber length measuring instrument, such as 0-2000m or 0-20.00Km.... etc..
Step 2, tentatively by 200,000 kilometers/S of light velocity estimation optical signal required time in gamut length of fibre in optical fiber
tm。
Step 3 tests the circuit delay t for determining that Fig. 1 shows measuring system0。
Step 4 presses (tm+t0) it should be less than square-wave modulation signal half period principle, select the cycle T of modulated signal.
Step 5, the low level value V of output end when measuring XOR circuit homophase inputLIt is defeated when with anti-phase input
The high level V at end outHValue.
Step 6, according to above data, when drawing fiber lengths equal to zero and half range length, XOR circuit output
The waveform diagram of end in one cycle, as Fig. 8 shows.By waveform diagram, so that it may obtain and calculate VbAnd VrefExpression formula:
With
Since fiber core refractive index has deviation near 1.5, the light velocity in optical fiber also inaccuracy be equal to 200,000 kilometers/
Second.VrefExact value is subject to actual value when calibrating adjusting.
According to calculated result, integrating resistor R is selectedintResistance value makes double-bevel analog-digital converter filling during timing sampling
Electric current should not be excessive.Otherwise, timing sampling is also not finished, and integrating circuit output just reaches saturation state in Fig. 6.Such case
Under, relational expression (5) is invalid.
The foregoing is merely illustrative of the preferred embodiments of the present invention, is not intended to limit the invention, all in essence of the invention
Made any modifications, equivalent replacements, and improvements etc., should all be included in the protection scope of the present invention within mind and principle.
Claims (10)
1. a kind of digital optical fiber length measuring system of XOR logic, which is characterized in that the digital optical fiber of the XOR logic
Length measuring system is provided with signal source of clock；
Signal source of clock is connect by square-wave signal with clock signal electro-optical conversion circuit, and clock signal electro-optical conversion circuit passes through
Optical signal is connect with transmission fiber；
Transmission fiber is connected by the photoelectric conversion and regenerative circuit of optical signal and clock signal, clock signal photoelectric conversion and again
Raw circuit passes one input terminal of linear transducer with XOR logic optical fiber by square-wave signal and connect, and XOR logic optical fiber passes length
Sensor output is connect by DC level with double-bevel analog-digital converter；
The clock signal electro-optical conversion circuit is connect by reference to signal with the channel digital oscilloscope CH1；Clock signal electric light
Conversion circuit passes another input terminal of linear transducer with XOR logic optical fiber simultaneously by reference to signal and connect；Clock signal
Photoelectric conversion and regenerative circuit are connect with the channel digital oscilloscope CH2 simultaneously by regenerated signal.
2. the digital optical fiber length measuring system of XOR logic as described in claim 1, which is characterized in that signal source of clock accounts for
Sky can switch between the two than the square-wave generator for 50%, period in 16 μ S and 32 μ S.
3. the digital optical fiber length measuring system of XOR logic as described in claim 1, which is characterized in that clock signal electric light
Conversion circuit makees light source device with the semiconductor laser LD of tail optical fiber using wavelength 1310nm, connects in transistor BG1 collector electricity
Lu Zhong；Signal source of clock exports the base stage for being connected to transistor BG1；LD light power regulating device is transistor BG1 transmitting
Potentiometer W1 in polar circuit.
4. the digital optical fiber length measuring system of XOR logic as described in claim 1, which is characterized in that clock signal electric light
The emitter of transistor BG1 connects the input terminal of phase inverter IC1 in conversion circuit, and the output end of inverter ic 1 is as reference
Signal output end.
5. the digital optical fiber length measuring system of XOR logic as described in claim 1, which is characterized in that in clock signal light
Electricity conversion and regeneration are adjusted in circuit, and response wave length scope is used to make Photoelectric Detection for the PIN photodiode of 900-1700nm
Device is connected to regeneration and adjusts in circuit between the base stage and GND of triode BG2；Potentiometer W2 and resistance Rb1After series connection, as crystalline substance
The below-center offset resistance of body triode BG2；Adjusting potentiometer W2 can be changed the saturation depth of BG2.
6. the digital optical fiber length measuring system of XOR logic as described in claim 1, which is characterized in that transistor
The collector of BG2 is connect with the non-inverting input terminal of open-loop voltage amplifier K, output end and the inverter ic 2 of voltage amplifier K
Input connection, the output end of inverter ic 2 is as regenerated signal output end.
7. the digital optical fiber length measuring system of XOR logic as described in claim 1, it is characterised in that: optical fiber length measuring
Instrument using XOR circuit as fiber lengths sensor, utilize the simulation trial function of 7107 double-bevel analog to digital conversion circuits
The digitized measurement of real world fiber length；It adjusts and calibrates equipped with zero point and adjust potentiometer；Two input terminals of XOR circuit
The reference signal output end and clock signal photoelectric conversion and regeneration connect in clock signal electro-optical conversion circuit respectively adjusts circuit
In regenerated signal output end；XOR circuit output end is followed by 31 foot V in of 7107 analog-digital converter of double-bevel through dividing
+ end；The 30 foot V in- termination zero point of 7107 double-bevel analog-digital converters adjusts the movable end of potentiometer W1,7,107 36 feet
Rref+Termination calibration adjusts the movable end of potentiometer W2.
8. the digital optical fiber length measuring system of XOR logic as described in claim 1, which is characterized in that the school of light power meter
The long 1310nm of quasi wave, range 0-2000 μ W, to monitor optical signal magnitude；Circuit is adjusted with clock signal photoelectric conversion and regeneration
Share same PIN photodiode；PIN photodiode is respectively connected to light power meter or clock signal by switching switch K
Photoelectric conversion and regeneration are adjusted in circuit.
9. the digital optical fiber length measuring system of XOR logic as described in claim 1, it is characterised in that: pass through optical patchcord
Realize that semiconductor laser LD and clock in tested optical fiber and clock signal electro-optical conversion circuit believe with fiber active linker
The optical coupling between PIN photodiode in number photoelectric conversion circuit.
10. the digital optical fiber length measuring system of XOR logic as described in claim 1, it is characterised in that: in order to adjust and
Monitor regenerated signal reproduced state, also in clock signal electro-optical conversion circuit reference signal output end and photoelectric conversion and
The regenerated signal output end that regeneration adjusts in circuit is respectively connected to the channel CH1 and the channel CH2 of digital oscilloscope.
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| CN114397093A (en) * | 2022-01-21 | 2022-04-26 | 四川中久大光科技有限公司 | A fiber laser power monitoring system and safety interlocking method |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN114397093A (en) * | 2022-01-21 | 2022-04-26 | 四川中久大光科技有限公司 | A fiber laser power monitoring system and safety interlocking method |
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Application publication date: 20190816 |