CN2691489Y - Multiple wave-length near-infrared instrument for testing blood-oxygen content in brain tissue - Google Patents
Multiple wave-length near-infrared instrument for testing blood-oxygen content in brain tissue Download PDFInfo
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- CN2691489Y CN2691489Y CN 200320125532 CN200320125532U CN2691489Y CN 2691489 Y CN2691489 Y CN 2691489Y CN 200320125532 CN200320125532 CN 200320125532 CN 200320125532 U CN200320125532 U CN 200320125532U CN 2691489 Y CN2691489 Y CN 2691489Y
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- operational amplifier
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Abstract
The utility model discloses a multiple wave-length near-infrared instrument for testing blood-oxygen content in brain tissue, which is composed of a light source part and a test part containing a photoelectric conversion circuit and a transmittal circuit. The light source part is provided with a pulse generating circuit and a lamp driving circuit, and the output of the pulse generating circuit is connected to the lamp driving circuit; in the detection part, the photoelectric conversion circuit is provided with two sets of or more than two sets of photodiodes and the corresponding primary transmittals; a filter which can detect different monochromatic lights is arranged on each photodiode, and a trap circuit is connected between the photoelectric conversion circuit and the transmittal circuit. The back part of the test part is provided with a data-processing part formed from the sequential connection of an interface sampling circuit, a digital-analogue conversion chip, and a monolithic computer controlled system. The input of the interface sampling circuit is connected to the transmittal circuit of the test part. The utility model can directly make a remote or a real-time test and treatment to the blood-oxygen content in the patient's brain tissue. The accuracy rate is high, the volume is small, and the use is easy.
Description
Technical field
This utility model relates to a kind of instrument of guarding cerebral tissue blood, oxygen content, especially with the optical means non-invasive monitoring cerebral tissue blood of physics, the detector of oxygen content.
Background technology
At present, cerebral tissue blood, oxygen content detector are according to the principle difference, various dissimilar products are arranged, the instrument that the near infrared ray spectrophotometric does not have the development of wound determination techniques is wherein the most widely used a kind of, as RunMan instrument of the U.S. etc., but function, the detection data of the cerebral tissue blood that prior art is used, the storage of oxygen content detector no signal and record need be equipped with hodoscope and trace demonstration, and must dispose modulus A/D in addition and change external computer analysis data, the huge mobile inconvenience of its function limitation and adnexa.
The utility model content
The purpose of this utility model is to provide a kind of multi-wavelength Near-infrared Brain to organize blood, oxygen content detector, can long-range, real-time detection store, print, report patient's cerebral tissue blood, oxygen content simultaneously, and the little convenience of volume moves.
In order to achieve the above object, this utility model has been done following improvement on the existing multi-wavelength Near-infrared Brain tissue blood oxygen content detector basis that is made of the Lights section and the test section that comprises photoelectric switching circuit, discharge circuit:
1) the Lights section is provided with pulse generating circuit and lamp drive circuit, and the outfan of pulse generating circuit is connected to lamp drive circuit;
2) test section two groups to the five groups photodiodes and the respective primary amplifier that are included in that photoelectric switching circuit is provided with installs the optical filter of penetrating different wavelengths of light additional at photodiode surface, adds connecing trap circuit between photoelectric switching circuit and the discharge circuit;
3) add data processing section behind the test section, this part is connected and composed in turn by sampling interface circuit, D/A converting circuit, Single Chip Microcomputer (SCM) system, and the discharge circuit in the testing circuit outputs to the sampling interface circuit.
And, the pulse generating circuit of the Lights section comprises operational amplifier U4B, diode D3, D4 and resistance R 6, R7, R8, R9, R10 and capacitor C 3, diode D3, D4 and resistance R 6 backs in parallel and capacitor C 3, resistance R 7 are composed in series the end of oppisite phase that integrator feeds back to operational amplifier U4B, and resistance R 8, R9, R10 are composed in series positive feedback; The lamp drive circuit of the Lights section comprises operational amplifier U4A and Darlington transistor Q1, resistance R 11, R12, R13, R14, R15, R16, R17, switch S, bulb G, two contact S1, S2 of switch S are connecting resistance R13 and resistance R 14 respectively, receive the positive terminal of operational amplifier U4A after resistance R 11, R12, R13, R14 are parallel with one another, resistance R16, R17 connect afterwards and bulb G parallel connection mutually on the emitter stage of Darlington transistor Q, and the end of oppisite phase of operational amplifier U4A is connected between resistance R 16, the R17.
And the respective primary amplifier of each photodiode is by operational amplifier and the amplifier formed with the placed in-line resistance of photodiode, the balance adjustment circuit of connecting between the feedback resistance of each amplifier in the photoelectric switching circuit; Trap circuit adopts the back of active twin-T network to add the active double T band elimination filter that operational amplifier constitutes, and joins two same active double T band elimination filters after the respective primary amplifier of every group of photoelectricity two machine pipes.
And the sampling interface circuit of data processing section is made up of 8 followers that select 1 analog switch U6 and operational amplifier U7 to constitute; The Single Chip Microcomputer (SCM) system of data processing section adopts latch U9 and encoder U10 as the controlling of sampling between single-chip microcomputer U11 and analog-digital chip U8, and Single Chip Microcomputer (SCM) system comprises built-in display, keyboard, hodoscope, memorizer and printer.
After adopting such circuit structure, the multi-wavelength Near-infrared Brain organizes blood, oxygen content monitor to need not optional equipment, and directly the convert light electric analoging signal is digital signal and carries out various date processing, and accuracy rate improves and be easy to use.
Description of drawings
Fig. 1 this utility model structured flowchart;
Fig. 2 the Lights section circuit diagram;
Fig. 3 test section circuit diagram;
Fig. 4 data processing section circuit diagram.
The specific embodiment
Referring to Fig. 1～4, this utility model is made of the Lights section and the test section that comprises photoelectric switching circuit, discharge circuit, and the Lights section is provided with pulse generating circuit 1 and lamp drive circuit 2, and the outfan of pulse generating circuit is connected to lamp drive circuit; The test section is provided with two groups to five groups photodiodes and respective primary amplifier at photoelectric switching circuit 3, installs the optical filter of penetrating different wavelengths of light additional at photodiode surface, adds connecing trap circuit 4 between photoelectric switching circuit 3 and the discharge circuit 5; Add data processing section behind the test section, this part is connected and composed in turn by sampling interface circuit 6, analog-digital chip 7, single-chip computer control system 8, and the discharge circuit in the testing circuit outputs to the sampling interface circuit.The light that detector sends is after tissue scattering/reflection, by the monochromatic light in the photodiode detection respective range wavelength of two groups of band optical filters, reception is converted into analog electrical signal, artificial circuit part at tester, analogue signal is carried out processing such as filtering, amplification, pass through mould/number conversion then, the result is stored in output under Single-chip Controlling.Obviously, according to the concrete needs of monochromatic wavelength that detect cerebral tissue blood, oxygen content, the photodiode of band optical filter can be provided with two groups to five groups, and respective primary amplifier, trap and amplifier part also are provided with corresponding two groups thereupon and get final product to five groups.
For the light-pulse generator of detector with variable intensity is provided, the pulse generating circuit 1 of the Lights section comprises operational amplifier U4B, diode D3, D4 and resistance R 6, R7, R8, R9, R10 and capacitor C 3, diode D3, D4 and resistance R 6 backs in parallel and capacitor C 3, resistance R 7 are composed in series the end of oppisite phase that integrator feeds back to operational amplifier U4B, and resistance R 8, R9, R10 are composed in series positive feedback; The lamp drive circuit 2 of the Lights section comprises operational amplifier U4A and Darlington transistor Q1, resistance R 11, R12, R13, R14, R15, R16, R17, switch S, bulb G, two contact S1, S2 of switch S are connecting resistance R13 and resistance R 14 respectively, receive the positive terminal of operational amplifier U4A after resistance R 11, R12, R13, R14 are parallel with one another, resistance R16, R17 connect afterwards and bulb G parallel connection mutually on the emitter stage of Darlington transistor Q, and the end of oppisite phase of operational amplifier U4A is connected between resistance R 16, the R17.
Operational amplifier U4B has formed multivibrator and has produced square wave, and D3, D4 and R6, C3 form integrator jointly output voltage is fed back to end of oppisite phase.D4 and the D3 voltage when conducting is constant substantially, therefore can play the amplitude limit effect when integrating circuit discharges and recharges, but also can be used as the indication whether vibration begins.R7 guarantees the normal operation of integrating circuit as divider resistance.R8, R9, R10 form positive feedback, make operational amplifier output to reach capacity rapidly.When the voltage on the integrating capacitor C3 during a little more than the voltage of operational amplifier positive terminal, operational amplifier output jumps to negative saturation value rapidly, when the voltage on the integrating capacitor C3 during a little less than the voltage of operational amplifier positive terminal, operational amplifier output jumps to positive saturation value rapidly, so circulation endlessly forms a series of square waves.When regulating R10, the dividing potential drop of positive terminal changes thereupon, and the time that the voltage on the integrating capacitor arrives the positive terminal magnitude of voltage also can change, thereby causes the change of the frequency of output square wave.
It is luminous that operational amplifier U4A and Darlington transistor Q form constant pressure source driving bulb, and this utility model Darlington transistor Q adopts TIP122.Its operation principle is, square wave process resistance R 11 from operational amplifier U4B output, R12, R13, be added to the positive terminal of operational amplifier U4A after the back-pressure effect of R14, principle according to operational amplifier " empty short ", the voltage of its end of oppisite phase should be identical with positive terminal, therefore can think that voltage and the voltage on the R11 on the R17 equate, simultaneously according to " empty disconnected " principle, can ignore by the positive terminal of operational amplifier and the electric current of end of oppisite phase, can think that the flow through electric current of R16 and R17 is equal, therefore when square wave is in high level, the constant voltage of the last generation of R16, the emitter stage of TIP122 also produces constant voltage, and bulb G will be luminous under the situation of constant voltage, keeps its light intensity constant.When square wave was in low level, the voltage on the R16 was zero, and the voltage of the emitter stage of TIP122 also is zero, and bulb extinguishes.When switch S switched to different gears, the dividing potential drop on the R11 also can be different, made the voltage of emitter stage of TIP122 change, thereby changed the supply voltage of bulb G, reached the purpose of the luminous intensity that changes the lamp source.
Use optical signal in order effectively to extract to detect, the respective primary amplifier of each photodiode is by operational amplifier and the amplifier formed with the placed in-line resistance of photodiode, the balance adjustment circuit of connecting between the feedback resistance of each amplifier in the photoelectric switching circuit 3; Trap circuit 4 adopts the back of active twin-T network to add the active double T band elimination filter that operational amplifier constitutes, and joins two same active double T band elimination filters after the respective primary amplifier of every group of photodiode.The device that is used for surveying optical signal in this utility model is photodiode D1 and D2, in order to detect monochromatic light, has added optical filter on the surface of photodiode, realizes the detection to the monochromatic light signal in the 760nm-850nm scope respectively.And the photodiode output current is little, generally has only several microamperes.After the optical signal that receives become proportional with it low current signal, be transformed into voltage signal by operational amplifier with amplifier that the placed in-line resistance of photodiode is formed.Its basic circuit as shown in Figure 3.Photodiode is equivalent to a current source, and when its load impedance was zero, output characteristics was best.And ideal amplifier just in time has the characteristic of " empty short " (promptly voltage difference is zero between two inputs), and this selects for use amplifier to come the reason of sense photodiode tube current just.Ideal amplifier input also has the characteristic of " empty disconnected " (being that input is not taken electric current), and the electric current that photodiode D1 and D2 produce flows through feedback resistance R1, and R2 is converted to voltage, thereby has realized the linear transformation of light → electric current → voltage.This utility model adopts the TLC277 integrated amplifier as amplifier U1A, U1B, and TLC277 is low noise high-performance amplifier, can well realize this conversion.The value of capacitor C 1 and C2 is very little, can allow signal freely pass through, and suppresses the higher-order of oscillation.R5, R6, R7 Compositional balance regulating circuit, the size that can regulate two paths of signals simultaneously makes it balance.Active double T trap circuit is adopted in trap circuit 4 designs of the present utility model, and the T network has the frequency-selecting effect, and is very big owing to the electric capacity capacitive reactance in low-frequency range, input signal transmits by resistance, very little in the capacitive reactance of high band electric capacity, input signal is by capacitive transmission, when signal frequency and characteristic frequency
When equating, impedance is very big, makes transmission coefficient almost nil, realize the trap effect, but its trap characteristic is poor, and does not have load-carrying ability.For realizing certain trap characteristic, add amplifier in the back of twin-T network and constitute active double T band elimination filter, this utility model cooperates every group of trap circuit of photodiode all to adopt two groups to repeat identical wave trap, constitute with twin-T network T1, T2, T3, T4 respectively by U2A and U2B, U3A and these two groups of amplifiers of U3B, trap characteristic is improved, improved circuit performance.And, be the main interference source of electrocardiosignal because the 50Hz power frequency is disturbed, this utility model design trap circuit parameter is specifically designed to it and filters the interference of 50Hz power frequency.Behind trap circuit and discharge circuit, the optical signal of two photodiode acceptance has been separately converted to analog electrical signal S760 and S850.
In order to be result with analog signal conversion, the sampling interface circuit 6 of data processing section is made up of 8 followers that select 1 analog switch U6 and operational amplifier U7 to constitute; The Single Chip Microcomputer (SCM) system 7 of data processing section adopts latch U9 and encoder U10 as the control connection between single-chip microcomputer U11 and analog-digital chip U8, and Single Chip Microcomputer (SCM) system comprises built-in display, keyboard, hodoscope, memorizer and printer.This utility model circuit utilizes the CD4051 chip to select 1 analog switch U6 as 8, realizes the time sharing sampling to signal in the 760nm-850nm scope.The sampling control signal of being sent here by single-chip microcomputer CD4051 when low level selects the X0 passage to connect, and the S760 signal is sent into analog-digital chip U8, selects the X1 passage to connect during high level, and the S850 signal is sent into analog-digital chip U8, realizes time sharing sampling with this.The follower output resistance that U7 forms is very little, has reduced the influence of back level load change to signal.Couple together by bus between the data output of the data input of single-chip microcomputer U11 and the data output between analog-digital chip U8, latch U9, between single-chip microcomputer U11 and the analog-digital chip U8 encoder U14 is set.This utility model adopts 3/8 decoder 74LSl38 as U10, A/D conversion chip AD574A is as U8, the sheet that the output Y1 of U10 connects U8 selects port CS, and sheet selects analog-digital chip U8, thereby data transaction, data under the realization single-chip microcomputer U11 control latch, the data transmission.Detector built-in display, keyboard, hodoscope, memorizer and printer, user can instant as required stored data or dateout.
Operation principle of the present utility model: with multi-wavelength cerebral tissue blood, the Lights section of oxygen detection places on the tested tissue, the light that sends is after tissue scattering/reflection, receive by the photoelectricity testing part in the detector, artificial circuit part at detector, analogue signal is carried out filtering, processing such as amplification, pass through mould/number conversion then, use single-chip computer control system 8, data are calculated and deposited it in memorizer, simultaneously the result is sent display screen to show brain blood, oxygen content changing value and blood, the oxygen waveform, and under the control of keyboard, carry out report output, its report output is finished by embedded printer, according to using needs, initial data can be deposited in the memorizer, the data consumer of storage can access at any time, input can be sent printer prints result and blood simultaneously, the oxygen waveform.Blood oxygen waveform also can be described on hodoscope.Needing can to provide output interface by single-chip microcomputer under the situation of computer processing data, output interface links to each other with computer, collects in the computer by the test result of interface with tester, carries out analyzing and processing by corresponding software.
Claims (5)
1. a multi-wavelength Near-infrared Brain tissue oxygenation detector is made of the Lights section and the test section that comprises photoelectric switching circuit, discharge circuit, it is characterized in that:
1) the Lights section is provided with pulse generating circuit and lamp drive circuit, and the outfan of pulse generating circuit is connected to lamp drive circuit;
2) test section two groups to the five groups photodiodes and the respective primary amplifier that are included in that photoelectric switching circuit is provided with installs the optical filter of penetrating different wavelengths of light additional at photodiode surface, adds connecing trap circuit between photoelectric switching circuit and the discharge circuit;
3) add data processing section behind the test section, this part is connected and composed in turn by sampling interface circuit, D/A converting circuit, Single Chip Microcomputer (SCM) system, and the discharge circuit in the testing circuit outputs to the sampling interface circuit.
2. multi-wavelength Near-infrared Brain tissue oxygenation detector according to claim 1, it is characterized in that: the pulse generating circuit of the Lights section comprises that computing puts people's device [U4B], diode [D3, D4] and resistance [R6, R7, R8, R9, R10] and electric capacity [C3], diode [D3, D4] and resistance [R6] back in parallel and electric capacity [C3], resistance [R7] are composed in series the end of oppisite phase that integrator feeds back to operational amplifier [U4B], and resistance [R8, R9, R10] is composed in series positive feedback; The lamp drive circuit of the Lights section comprises operational amplifier [U4A] and Darlington transistor [Q1], resistance [R11, R12, R13, R14, R15, R16, R17], switch [S], bulb [G], two contacts [S1, S2] of switch [S] are connecting resistance [R13] and resistance [R14] respectively, receive the positive terminal of operational amplifier [U4A] after resistance [R11, R12, R13, R14] is parallel with one another, resistance on the emitter stage of Darlington transistor [Q] [R16, R17] is series connection back and bulb [G] parallel connection mutually, and the end of oppisite phase of operational amplifier [U4A] is connected between the resistance [R16, R17].
3. multi-wavelength Near-infrared Brain tissue oxygenation detector according to claim 1 and 2, it is characterized in that: the respective primary amplifier of each photodiode is by operational amplifier and the amplifier formed with the placed in-line resistance of photodiode, the balance adjustment circuit of connecting between the feedback resistance of each amplifier in the photoelectric switching circuit; Trap circuit adopts the back of active twin-T network to add the active double T band elimination filter that operational amplifier constitutes, and joins two same active double T band elimination filters after the respective primary amplifier of every group of photoelectricity two machine pipes.
4. multi-wavelength Near-infrared Brain tissue oxygenation detector according to claim 1 and 2 is characterized in that: the sampling interface circuit of data processing section is made up of 8 followers that select 1 analog switch [U6] and operational amplifier [U7] to constitute; The Single Chip Microcomputer (SCM) system of data processing section adopts latch [U9] and encoder [U10] as the controlling of sampling between single-chip microcomputer [U11] and analog-digital chip [U8], and Single Chip Microcomputer (SCM) system comprises built-in display, keyboard, hodoscope, memorizer and printer.
5. multi-wavelength Near-infrared Brain tissue oxygenation detector according to claim 3 is characterized in that: the sampling interface circuit of data processing section is made up of 8 followers that select 1 analog switch [U6] and operational amplifier [U7] to constitute; The Single Chip Microcomputer (SCM) system of data processing section adopts latch [U9] and encoder [U10] as the controlling of sampling between single-chip microcomputer [U11] and analog-digital chip [U8], and Single Chip Microcomputer (SCM) system comprises built-in display, keyboard, hodoscope, memorizer and printer.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200320125532 CN2691489Y (en) | 2003-12-23 | 2003-12-23 | Multiple wave-length near-infrared instrument for testing blood-oxygen content in brain tissue |
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| CN 200320125532 CN2691489Y (en) | 2003-12-23 | 2003-12-23 | Multiple wave-length near-infrared instrument for testing blood-oxygen content in brain tissue |
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Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100453041C (en) * | 2005-10-20 | 2009-01-21 | 暨南大学 | Anesthesia depth monitor utilizing auditory stimulation and near infrared spectroscopy |
| CN101849821A (en) * | 2010-06-13 | 2010-10-06 | 华中科技大学 | Optical fiber near-infrared spectrometer |
| US8068891B2 (en) | 2006-09-29 | 2011-11-29 | Nellcor Puritan Bennett Llc | Symmetric LED array for pulse oximetry |
| CN101158676B (en) * | 2006-12-31 | 2011-12-14 | 重庆大学 | Analysis method and device for evaluating blood and crucifixes oxygen carrying and oxygen releasing function thereof |
| US8175667B2 (en) | 2006-09-29 | 2012-05-08 | Nellcor Puritan Bennett Llc | Symmetric LED array for pulse oximetry |
| US8532751B2 (en) | 2008-09-30 | 2013-09-10 | Covidien Lp | Laser self-mixing sensors for biological sensing |
| CN103424716A (en) * | 2012-05-17 | 2013-12-04 | 安徽宏实光机电高科有限公司 | Lamp tube detection system based on application of color sorter |
| US8649838B2 (en) | 2010-09-22 | 2014-02-11 | Covidien Lp | Wavelength switching for pulse oximetry |
| US8805465B2 (en) | 2010-11-30 | 2014-08-12 | Covidien Lp | Multiple sensor assemblies and cables in a single sensor body |
| US8818473B2 (en) | 2010-11-30 | 2014-08-26 | Covidien Lp | Organic light emitting diodes and photodetectors |
| CN106725323A (en) * | 2016-12-22 | 2017-05-31 | 中国科学院苏州生物医学工程技术研究所 | Wearable biological signal collecting device |
| CN108186028A (en) * | 2017-12-28 | 2018-06-22 | 中国科学院自动化研究所 | Contactless brain blood oxygen detecting system |
-
2003
- 2003-12-23 CN CN 200320125532 patent/CN2691489Y/en not_active Expired - Lifetime
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100453041C (en) * | 2005-10-20 | 2009-01-21 | 暨南大学 | Anesthesia depth monitor utilizing auditory stimulation and near infrared spectroscopy |
| US8068891B2 (en) | 2006-09-29 | 2011-11-29 | Nellcor Puritan Bennett Llc | Symmetric LED array for pulse oximetry |
| US8175667B2 (en) | 2006-09-29 | 2012-05-08 | Nellcor Puritan Bennett Llc | Symmetric LED array for pulse oximetry |
| CN101158676B (en) * | 2006-12-31 | 2011-12-14 | 重庆大学 | Analysis method and device for evaluating blood and crucifixes oxygen carrying and oxygen releasing function thereof |
| US8532751B2 (en) | 2008-09-30 | 2013-09-10 | Covidien Lp | Laser self-mixing sensors for biological sensing |
| CN101849821A (en) * | 2010-06-13 | 2010-10-06 | 华中科技大学 | Optical fiber near-infrared spectrometer |
| US8649838B2 (en) | 2010-09-22 | 2014-02-11 | Covidien Lp | Wavelength switching for pulse oximetry |
| US8805465B2 (en) | 2010-11-30 | 2014-08-12 | Covidien Lp | Multiple sensor assemblies and cables in a single sensor body |
| US8818473B2 (en) | 2010-11-30 | 2014-08-26 | Covidien Lp | Organic light emitting diodes and photodetectors |
| CN103424716A (en) * | 2012-05-17 | 2013-12-04 | 安徽宏实光机电高科有限公司 | Lamp tube detection system based on application of color sorter |
| CN106725323A (en) * | 2016-12-22 | 2017-05-31 | 中国科学院苏州生物医学工程技术研究所 | Wearable biological signal collecting device |
| CN108186028A (en) * | 2017-12-28 | 2018-06-22 | 中国科学院自动化研究所 | Contactless brain blood oxygen detecting system |
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| C14 | Grant of patent or utility model | ||
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| CX01 | Expiry of patent term |
Expiration termination date: 20131223 Granted publication date: 20050413 |