MXPA97008474A - Fluid analyzer with tu connector verifier - Google Patents

Abstract

Apparatus for analyzing fluids by providing, through a tube, comprising an analyzer instrument inside a container, a first connector coupled to the tube and having an end face, a second connector, which is coupled with the first connector and annexed to the container, a pair of optical fibers arranged inside the container, a first end of each of the fibers is mounted on the second connector, there is a clear optical path between the end face of each of the first ends of the fibers and at least one common point in the extreme face. A light source is optically coupled to the second end of a first of the fiber pair and an optical detector optically coupled to the second end of the second of said fiber pair.

Description

FLUID ANALYZER WITH PIPE CONNECTOR VERIFIER Field and Background of the Invention The present invention relates to a system for verifying the presence and identity of a tube connector connected to an instrument and, more particularly, to an electrooptical device and method side, to determine whether an assembly of tubes It has been connected to a fluid analysis instrument and, if applicable, if it belongs to a certain class of said tube assemblies.

The particular application for which the present invention will be described is that of a capnograph, which is an instrument for analyzing exhaled air. A capnograph is used to make samples of exhaled air by a patient, by means of a small tube, also called sample line, an end of which is, for example, connected to an air passage of a respirator or to a cannula attached to the holes nasal of the patient; The tube is connected at its other end, through a special connector, to the analyzer instrument. The tube assembly, especially of the type that is subject to the present invention, often includes a filter or other means for removing moisture and mucus; as an alternative, there may be a filter constructed within the capnograph or may be provided separately, to be connected to the tube. The complete tube assembly, which includes the filter and the connector, is usually of the disposable type and is replaced by each patient tested.

A typical connector, also called luer, is shown in Figure 1, which shows the two limbs, one male and one female, separated; each member is illustrated in an ismerical view and in a longitudinal section. The shape of the connector, which is essentially round, as shown in Figure 1, is standardized in industry, so that tube assemblies from various manufacturers can be used interchangeably with any analyzer instrument. Thus, the manufacturer of a particular type of analyzer instrument generally has no control over what type of tube and filter will be used with his instrument in practice. For reasons of optimal performance of the instrument, as well as for commercial reasons, the analyzer instrument manufacturer may wish to exercise such control. In particular, you may want to stipulate that only a certain class of pipe assemblies be connected to, and used with, your instrument. Such a class may, for example, consist of assemblies of tubes that include a filter, in general, or so that they are manufactured directly by him to his specifications or under his supervision or license, in particular.

One way to enforce this stipulation would be to use some kind of security key arrangement between the connector and the instrument. Such an arrangement would, however, be incompatible with the shape of the standard connector that is used everywhere and would require the operator, when connecting and disconnecting the tube, different movements than those to which it is accustomed.

Another way to force the stipulation is to have a system by means of which the correct tube assembly would be identified as such by means of the instrument, after which its operation would be allowed, and to vacate the instrument to the contrary. A secondary benefit of such an arrangement would be that the instrument would be prevented from operating when no tube is connected at all or when even a correct tube is connected inappropriately, thus avoiding damage to the sensitive parts of the instrument and thus causing incorrect readings. Yet another purpose can be achieved by such a system, namely the identification of the tube assembly as belonging to one of a number of classes and informing the instrument of the particular identity detected, so that it is automatically allowed to operate in a different manner for the different classes.

Various types of means for effecting said identification are known. One type is electromechanical, by means of which the connector would have one or more engravings or notches on its end, which would fit appropriately to placed levers that activate micro switches. This type of media is impractical, due to the small dimensions of the pair of connectors and the small space available in the adjacent instrument panel. Another type of means is electrical, by means of which the connector would have one or more conductive paths at its end, which would complete the circuit between the contacts placed in an appropriate manner. This type of medium is impractical, due to the prevailing humidity in the immediate environment.

There is thus a widely recognized need for, and it would be highly advantageous to have, a fluid analysis system that includes the ability to determine that a tube assembly has been properly connected to the analyzer instrument and that the tube is of a certain kind. Said capacity must be compatible with the standard form of connectors used, as well as with the medical environment, it must be reliable and preferably it must be inexpensive - at least with respect to the manufacture of the disposable tube assembly.

SUMMARY OF THE INVENTION The present invention successfully addresses the aforementioned needs by providing an air analysis system in which the presence and classification of a connected tube assembly can be detected conveniently and reliably.

The present invention presents a novel modification of an air analysis system, by means of which the presence of a tube connector of an acceptable kind and its proper positioning with respect to the corresponding connector, is ensured by making the connector end appropriately reflective and by shining light on it and detecting the reflected light of it.

More specifically, the system of the present invention provides a reflective surface specularly at the end of the tube connector of the acceptable class and a pair of optical fibers mounted on the corresponding connector so that when, that tube connector is correctly positioned, a Sufficient portion of light emitted from the end of one fiber is reflected inside the end of the other fiber. The light emitted originates from an electro-luminescent diode (LEO), optically coupled to the first fiber. The light reflected inside the other fiber is detected by means of a photodiode connected to a circuit that includes a comparator. The latter emits a binary signal that can be used to activate or deactivate the essential components of the analyzer instrument.

• In an alternative configuration, the end of the tube connector has a fluorescent or fluorescent material, which can be stimulated by the light emitted from the first fiber to re-emit light of spectral characteristics different from those of the LED.

A portion of the re-emitted light is collected by the second fiber and passed through a spectrally selective filter, and then detected as in the first configuration.

According to the present invention there is provided an apparatus for analyzing fluids provided to it through a tube and a system for verifying the proper connection of the tube thereto and for classifying the tube, comprising: an analyzer instrument within a container; a first connector coupled to the tube and having a final face; a second connector, corresponding to the first connector and coupled to the container; a pair of optical fibers disposed within the container, a first end of each of said optical fibers mounted on the second connector so that, when the first connector properly engages with the second connector, there is a clear optical path between the end face from each of the first ends of the fibers and at least one common point on the end face; a light source optically coupled to the second end of a first fiber; and a light detector optically coupled to the second end of the second fiber.

According to other features in preferred specimens of the invention described below, the end face is essentially spectrally reflective in at least one annular portion thereof, the analyzer instrument is operative only upon receipt of an activation signal and further comprises an electrical circuit connected to the light detector, the circuit is configured such that only if a substantial portion of any light emitted from the first end of one of the fibers is reflected by the annular portion of the end face within the first end of the other of the fibers. fibers, the circuit will emit the activation signal to the analyzer instrument.

Preferably, the light source emits light in a thin band of wavelengths and the apparatus further includes an optical filter, essentially transmitting the thin band of wavelengths and arranged in the path of light transmitted through the second wavelength. fiber. According to a modification of the preferred specimen, the reflectivity of the extreme face is spectrally selective and the light source emits light in a thin band of wavelengths or there is a spectrally selective optical filter arranged in the path of the light transmitted from the second fiber.

According to another configuration, the end face is covered with a fluorescent or phosphorescent material, the light source emits light in a first band of wavelengths, so as to stimulate the fluorescent or phosphorescent material to emit light in a second band of lengths of wave and the apparatus further includes an optical filter, essentially transmitter of at least one wavelength of the second band and arranged in the path of light transmitted through the second fiber. According to a modification of this configuration, the second band of wavelengths is different between a plurality of types of material and the optical filter of a particular apparatus is transmitter of the band corresponding to only one type.

According to other characteristics in the second configuration described, the light source emits light in a first pulse train and the circuit further includes a synchrony detector which is fed by means of a multiplier signal formed as a second pulse train, the Two trains of pulses have equal rhythms and the second train is delayed with respect to the first train.

Also presented herein is a method for verifying the proper connection of a tube to a tube analyzer instrument and for classifying the connected tube, using a system essentially presented herein.

BRIEF DESCRIPTION OF THE DRAWINGS The invention is described herein, by way of example only, with reference to the accompanying drawings, wherein: Figure 1 is an illustration of a typical tube connector within a system that is subject to the present invention; Figure 2 is an orthogonal drawing of the connector in Figure 1, modified in accordance with the present invention; Figure 3 is an orthogonal drawing of the connector corresponding to that of Figure 2, modified in accordance with the present invention.

Figure 4 is a schematic block diagram of an electrical circuit according to the example cited in the present invention.

DESCRIPTION OF PREFERRED EMBODIMENTS The present invention is a system for detecting the presence of a tube connector at the entrance of an instrument and for identifying it as belonging to a certain class, so as to affect a decisive process in the instrument.

Specifically, the present invention can be used to verify whether an acceptable type of tube assembly has been connected to the panel of a capnograph.

The principles and operation of the connector identifier according to the present invention can be better understood with reference to the drawings and the accompanying description.

Referring now to the drawings, Figure 2 illustrates the essential part of the female member 10 of the tube connector, modified according to the preferred example of the invention. Basically, this is the standard female connector member (which will hereafter be referred to simply as a connector), as shown in Figure 1, typified by means of a slightly cylindrical internal wall 11. The modification requires that the annular face 12 of its end (which is the closest end of the instrument panel) is spectrally reflective to light. Reflectivity can be obtained, for example, by covering the surface with an appropriate reflective layer 813) or by polishing the surface until a glossy surface is obtained. A favorite method is the hot press (or stamped) of a reflective film called SLM aluminum, available by art from Kurz, Ltd, Germany; it is particularly appropriate when the connector material is made of ABS. As will be appreciated hereafter, the reflective surface needs not to extend over the entire extension of the end face 12, but it must form a complete annular ring, since the luer can be connected to the panel in any angular orientation. A female connector will be such with a reflective annular surface at its end face will be called from here as an appropriate connector, and any other connector - as an inappropriate connector.

Figure 3 shows a front view of the essential part of the corresponding male connecting member 14, which is mounted on the panel of the analyzer instrument; the central, slightly conical notch 16 fits within the end of the female connector 10 of Figure 2 in such a way that the end face 12 of the connector 10 is parallel to, and to some extent of, the annular surface 18 of the surrounding male connector 14 the central groove 16. Through the rear platform 19 of the male connector 14 two small holes 15 have to be drilled, at a mutual distance of about 1.5 mm from center to center, so that openings facing the face are formed 12. Within each of the recesses 15, one end of one of the two optical fibers 21 and 22 running inside the instrument is respectively mounted. The fibers are mounted so that their ends are flush with or slightly sunken behind the annular face 18 of the rear platform 19.

The other end of the fiber 21 is optically coupled to an electro-luminescent diode (LED) 23, while the other end of the fiber 22 is optically coupled to a photodiode (PD) 24. Both the LED 23 and the PD 24 are mounted at a convenient location within the instrument and are, respectively, connected to the electric circuits 25 and 26. The electric circuit 15 generates a train of current pulses, at a rate of, say, approximately 1kHz, which are guided through of LED 23 and cause corresponding pulses of light to be emitted. The frequency of the pulse train is chosen so that this light can be easily discriminated from ambient light, including artificial light (which usually has energy line frequencies and their harmonies). These light pulses are transmitted through the fiber 21 and are emitted at its end which is mounted on the connector 14. If an appropriate male connector 10 is in place, its reflective end face 12 reflects an appreciable portion of the pulsed light emitted into the adjacent end of the fiber 22, which transmits it to the PD 24. This reflected and retransmitted light is detected by the PD 24, which converts it to corresponding pulses of current in circuit 26. It is noted that, according to the standards of the dimensions of the connectors, the distance between the end face 12 and the surface 18 can be between 0.6 and 1.8 mm and this ensures the proper coupling of light between the fibers by specular reflection of the end face; however, to ensure that the distance is not less than 0.6 mm, a pair of 0.6 mm spacers 17 are mounted on the surface 18 of appropriate size.

It is appreciated that the LED is provided within a preferred specimen, but that other sources of light can be used to couple the fiber 21.

Referring now to Figure 4, the circuit 25 includes an amplifier 31, to which the input of the PD 24 is connected, followed in order by the synchronization detector 32, integrator 33 and comparator 34. The amplifier 31 amplifies the induced impulses in PD 24, then the synchronization detector 32 multiplies them by a train of pulses in synchrony obtained in the circuit 25. The last operation is advantageously performed to distinguish between the reflected light pulses and any ambient light that could penetrate the fiber 22. The resulting signal is rectified, to produce a direct voltage. The voltage is integrated by means of the integrator 33 for a certain period of time - to produce a voltage value, which is compared by the comparator 34 with a threshold value, which results in a binary signal. This signal, indicating whether the light pulses have been reflected or not from the fiber 21 within the fiber 22 and, therefore, - if the appropriate connector is properly in place, is applied to other parts of the instrument , to activate or deactivate the operation of the crucial components, such as the fluid suction pump and to turn on or off an alarm, or indicator or light.

The threshold value is chosen to be one that would discriminate between integrated voltage values resulting from the specular reflection of the light pulses of the fiber 21 and 22., as effected by the end face 12 of an appropriate female connector 10 (is say, one that has been treated according to the present invention) placed appropriately, on the one hand, and values that result from diffuse reflection, as can be effected by the uncovered face and untreated from any other female connector (which is , therefore, considered as an inappropriate connector), or from an appropriate connector improperly placed, on the other side.

It is appreciated that the circuit 25 can also generate current waveforms other than the pulses and that the circuit 26 can detect the resulting signals in a manner similar to that described above or in any other manner known in the art. According to the refinement of the apparatus presented herein, an optical fiber is placed, which selectively transmits the band of wavelengths emitted by the LED 23, either in front of the fiber 22 within the corresponding recess 15, or between the fiber 22 and PD 24; this filter is also instrumental in the distinction between ambient light and emitted light.

According to an alternative configuration of the present invention, the reflecting coverage on the end face 12 of the female connector 10 is made to be spectrally selective, that is, it is made to reflect light at certain wavelengths or within a certain bandwidth. The above can be achieved, for example, by making the reflective material contain dyes or pigments, or by covering the reflective layer with an appropriate spectral filter. This configuration can be advantageously applied, for example, by dividing between several subclasses of tube assemblies and matching each subclass to a corresponding type of analyzer instrument. For such an application, each type of instrument has a light source having a unique spectral characteristic and the reflection spectrum of each subclass of the tube assembly is made to correspond. As an alternative, the bandwidth of the light source is wide and identical in all types of instruments, but a filter in the path of reflected light (as described above) has a unique spectral characteristic, conforming to one specimen practical, this filter can be identical to that placed on the reflecting surface of the extreme face (as suggested above).

According to another alternative configuration of the present invention, the extreme face 12 of the female connector 10 is covered with a fluorescent or phosphorescent material, which is not necessarily spectrally reflective. The LED 23 is of a type that emits wavelengths short enough to stimulate fluorescence or phosphorescence in the material. There an optical filter is placed either in front of the fiber 22 within the corresponding gap 15, or between the fiber 22 and the PD 24. The optical fiber selectively transmits the strongest wavelengths emitted by the fluorescent or phosphorescent material, while which substantially attenuates the wavelengths emitted by the LED 23. The rest of the apparatus is as described above. Although this configuration involves higher costs to treat the connector end than the rest of the configuration, it has two advantages: a) There is a high degree of discrimination between light reflected from an appropriate connector and light reflected from any other connector , since the optical filter can be made to attenuate the band of wavelength emitted by the LED 23 (which is the only one present in the light reflected by inappropriate connectors). b) Different types of fluorescent and phosphorescent materials, which have different characteristics of spectral emission (or spectral profile) can be chosen; these can be assigned to different kinds of connectors for discrimination between them.

The second advantage can be realized, for example, by choosing for a particular instrument an optical filter that transmits one or more wavelengths in which the corresponding type of material emits strongly or more strongly, while substantially attenuating those lengths wave in which other types emit strongly. By appropriately adjusting the threshold level, the above would result in an activation signal issued by the comparator only when a connector of the corresponding class is appropriately connected to the instrument.

The fluorescent or phosphorescent material, instead of being covered, or painted on the extreme face, can also be incorporated into the material of which the extreme face (or all the connector) is made. Another way of applying it to the end face is to join or stamp (for example, by hot press) to the end face an aluminum or a film containing said fluorescent or phosphorescent material.

According to a refinement of the alternative configuration, applicable in the case of the phosphorescent materials, a certain time delay is introduced between the current pulse train applied to the LED 23 and the synchronized pulse train obtained from the circuit 25 and applied to the multiplier. in circuit 26. The time delay is only greater than the duration of a pulse. The effect of the time delay is that the light detected is only that which is emitted by the phosphorescence, excluding, in particular, the light directly reflected. This feature also helps to discriminate between an appropriate connector and any other connector and can be used in addition to, or as an alternative to, the aforementioned optical filter.

While the present invention has been described with respect to a limited number of copies, it will be appreciated that many variations, modifications and other applications of the invention can be made.

Claims (50)

1. CLAIMS: 1. Apparatus for analyzing fluids provided through a tube, comprising: (a) an analyzer instrument inside a container; (b) a first connector coupled to the tube and having a final face; (b) a second connector, corresponding to the first connector and coupled to the container; (c) a pair of optical fibers disposed within the container, a first end of each of said optical fibers mounted on the second connector so that, when the first connector properly engages with the second connector, there is a clear optical path between the end face of each of the first ends of the fibers and at least one common point on the end face; (d) a light source optically coupled to the second end of a first fiber; and (e) a light detector optically coupled to the second end of the second fiber.
2. 2. The apparatus of Claim 1, wherein said end face is characterized by essentially specular reflectivity in at least one annular portion thereof which, when said connector appropriately engages said second connector in any annular orientation, includes all possible minus a common point.
3. 3. The apparatus of Claim 2, wherein said analyzer instrument or any components thereof are operative only upon receipt of an activation signal and further comprising an electrical circuit connected to said light detector, said circuit being configured so that only if a substantial portion of any light emitted from said first end of one of said fibers is reflected by said annular portion of said end face within said other of said fibers, said circuit will emit said activation signal to said analyzer instrument.
4. 4. The apparatus of Claim 1, wherein said light source emits an essentially thin band of wavelengths and further comprises an optical filter, essentially transmitter for said band of wavelengths and arranged in the path of the light transmitted through of said second of said fibers.
5. 5. The apparatus of Claim 1, wherein said end face is covered with a fluorescent or phosphorescent material in at least one annular portion thereof when said first connector is properly coupled to said second connector in any annular orientation, includes all possible ones of said at least one common point.
6. 6. The apparatus of Claim 5, wherein said light source emits light in a first band of wavelengths, so as to stimulate said fluorescent or phosphorescent material to emit light in a second band of wavelengths, and further comprising a optical filter, essentially transmitter of at least one wavelength of said second band and disposed in the path of light transmitted through said second of said fiber pair.
7. 7. The apparatus of Claim 6, wherein said fluorescent or phosphorescent material is one of a plurality of types, characterized in that said second band of wavelengths has an essentially different spectral profile among said plurality of types, and wherein said optical filter is essentially transmitter for one or more wavelengths in which said one of said plurality of types emits in a strong and substantially attenuating manner for wavelengths in which any other of said types emits strongly.
8. 8. The apparatus of Claim 5, wherein said analyzer instrument or any components thereof are operative only upon receipt of an activation signal and further comprising an electrical circuit connected to said light detector, said circuit being configured so that only if a substantial portion of any light emitted from said fluorescent or phosphorescent material is collected by said first end of said second of said fibers, said circuit will emit said activation signal to said analyzer instrument.
9. 9. The apparatus of Claim 8, wherein said light source emits light as a first pulse train and said circuit further includes a synchrony detector which is fed by a multiplier signal formed as a second pulse train, the two pulse trains they have equal rhythms and said second train is delayed with respect to said first train.
10. 10. The apparatus of the Claim wherein said light source emits pulses.
11. 11. A system for verifying the proper connection of a tube assembly to an instrument for analyzing fluids and for classifying the connected tube assembly, the connection is made by means of a first connector, which is part of the tube assembly and which has a face end, and a second connector, which is coupled with the first connector and attached to a container enclosing the analyzer instrument, the system comprises: (a) a pair of optical fibers disposed within the container, a first end of each of said optical fibers mounted on the second connector so that, when the first connector appropriately couples with the second connector, there is a clear optical path between the end face of each of the first ends of the fibers and at least one common point on the fibers. the extreme face; (b) a light source optically coupled to the second end of a first of said fiber pair; and (c) a light detector optically coupled to the second end of the second of said fiber pair.
12. 12. The system of Claim 11, wherein the end face is made to have essentially specular reflectivity in at least one annular portion thereof, when the first connector is properly coupled to the second connector in any angular orientation, includes all possible ones of minus one point in common.
13. 13. The system of Claim 12, further comprising an electrical circuit connected to said light detector, said circuit is configured such that only its a substantial portion of any light emitted from said first end of one of said fibers is reflected by said portion. In the case of an annular end face inside said first end of the other of said fibers, the circuit will emit an activation signal to the analyzer instrument.
14. 14. The system of Claim 11, further comprising an optical filter, transmitter in an essentially thin band of wavelengths and disposed in the path of light transmitted through said second of said fibers.
15. 15. The system of Claim 11, wherein the end face is covered with a fluorescent or phosphorescent material in at least one annular portion thereof, when the first connector properly engages the second connector in any annular orientation, includes all possible said at least one common point.
16. 16. The system of Claim 15, wherein said light source emits light in a first wavelength band, such that said fluorescent or phosphorescent is stimulated to emit light in a second band of wavelengths, and further comprises a optical filter, essentially transmitter in at least one wavelength of said second band and arranged in the path of the light transmitted through said second of said fibers.
17. 17. The system of Claim 16, wherein said fluorescent or phosphorescent material is one of a plurality of types, characterized in that said second wavelength band has a different spectral profile among a plurality of types, and wherein said optical filter is essentially transmitter of one or more wavelengths in which said one of said plurality of types strongly emits and attenuates substantially for the wavelengths in which any other types emit strongly.
18. 18. The system of Claim 15 wherein the analyzer instrument and any other components thereof are operative only upon receipt of an activation signal and further comprising an electrical circuit connected to said light detector, said circuit being configured so that only its a substantial portion of any light emitted from said first end of one of said fibers is reflected by said annular portion of the end face within said first end of the other of said fibers, the circuit will emit an activation signal to the analyzer instrument.
19. 19. The system of Claim 18, wherein said light source emits light in a first pulse train and said circuit further includes a timing sensor that is fed with a multiplier signal formed as a second pulse train, the two pulse trains it has equal rhythms and said second train is delayed with respect to said first train.
20. 20. The system of Claim 11, wherein said light source emits light in pulses.
21. 21. A method for verifying the proper connection of a tube to a fluid analyzer instrument and for classifying the connected tube, the connection is made by a first connector coupled to the tube and having an end face and a second connector, corresponding to the first connector and coupled to a container enclosing the analyzer instrument, the method comprises the steps of: (a) providing a pair of optical fibers disposed within the container, a first end of each of said optical fibers mounted on the second connector so that, when the first connector is properly coupled with the second connector, there is a clear optical path between the end face of each of the first ends of the fibers and at least one common point on the end face; (b) providing a light source optically coupled to the second end of a first of said fiber pair; and (c) providing a light detector optically coupled to the second end of the second of said fiber pair.
22. 22. The method of Claim 1, further comprising the step of making the end face have essentially specular reflectivity in at least one annular portion thereof, when the first connector is properly coupled with the second connector in any angular orientation, even all the possible ones of said at least one common point.
23. 23. The method of Claim 22, further comprising the step of providing an electrical circuit connected to said light detector, said circuit is configured so that only its a substantial portion of any light emitted from said first end of one of said fibers is reflected by said annular portion of the end face within said first end of the other of said fibers, the circuit will emit an activation signal to the analyzer instrument.
24. . The method of Claim 21, further comprising the step of providing an optical filter, transmitter for an essentially thin band of wavelengths and disposed in the path of light transmitted through said second of said fiber pair.
25. 25. The method of Claim 21, whereby the end face is covered with fluorescent or phosphorescent material in at least one annular portion thereof, when the first connector properly engages the second connector in any annular orientation, includes all the possible ones of said at least one common point.
26. 26. The method of Claim 25, whereby the light source is caused to emit light in a first wavelength band in a first wavelength band, so as to stimulate said fluorescent or phosphorescent material to emit light in a second band of wavelengths, and further comprising the step of providing an optical filter, essentially transmitting at least one wavelength of said second band and disposed in the path of the light transmitted through said second of said pair of fibers.
27. 27. The method of Claim 26, wherein said fluorescent or phosphorescent material is chosen to be one of a plurality of types, characterized in that said second band of wavelengths has an essentially different profile among said plurality of types, and by means of the which said optical filter is made to be essentially transmitter of one or more wavelengths in which said one of said plurality of types emits strongly and substantially attenuates the wavelengths in which said other types emit stronger.
28. 28. The method of Claim 25, further comprising the step of providing an electrical circuit connected to said light detector, said circuit is configured so that only its a substantial portion of any light emitted from said first end of one of said fibers is reflected by said annular portion of the end face within said first end of the other of said fibers, the circuit will emit an activation signal to the analyzer instrument.
29. 29. The method of Claim 28, by means of which said light source is made to include a synchronization detector and said synchronization detector is fed with a multiplying signal formed as a second pulse train, the two trains of pulses have the same rhythms. and said second train is delayed with respect to the first train.
30. 30. The method of Claim 21, by means of which the light source emits light in pulses.
31. 31. A tube assembly for connection to a fluid analyzer instrument, comprising a connector having an end face, wherein said end face is formed to have essentially specular reflectivity in at least one annular portion thereof.
32. 32. A tube assembly for connection to a fluid analyzer instrument, comprising a connector having an end face, wherein said end face has a fluorescent or phosphorescent material in at least one annular portion thereof.
33. 33. The tube assembly of Claim 32, wherein said fluorescent or phosphorescent material is any of a plurality of types, characterized by different emission spectra.
34. 34. The tube assembly of Claim 31, wherein said formed end face includes hot stamping or printing with a reflecting aluminum.
35. 35. The tube assembly of Claim 31, wherein said formed end face includes cover or paint with reflective material.
36. 36. The tube assembly of Claim 31, wherein said formed end face includes a reflective object attached to said end face.
37. 37. The tube assembly of Claim 32, wherein said fluorescent or phosphorescent is covered or painted on said end face.
38. 38. The tube assembly of Claim 32, wherein said fluorescent or phosphorescent material is an object attached or stamped with said end face.
39. 39. The tube assembly of Claim 32, wherein said fluorescent or phosphorescent material is embedded in said end face.
40. 40. The tube assembly of Claim 31, wherein said reflectivity is spectrally selective.
41. 41. The tube assembly of Claim 31, further comprising an optical filter having spectrally selective transmission and disposed at least said annular portion.
42. 42. The apparatus of Claim 2, wherein said specular reflectivity is spectrally selective.
43. 43. The apparatus of Claim 42, wherein said light source emits light in a thin band wavelengths.
44. 44. The apparatus of Claim 42, further comprising an optical filter having a spectrally selective transmission and disposed in the path of the light emitted through said second of one of said fiber pair.
45. 45. The system of Claim 12, wherein said specular reflectivity is spectrally selective.
46. 46. The system of Claim 45, wherein said light source emits light in a thin band of wavelengths.
47. 47. The system of Claim 45, further comprising an optical filter having a spectrally selective transmission and disposed in the path of light emitted through said second of said fiber pair.
48. 48. The method of Claim 22, wherein said reflectivity is made to be spectrally selective.
49. 49. The method of Claim 48, whereby the light source is forced to emit in a thin band of wavelengths.
50. 50. The method of Claim 48 further comprising the step of providing an optical filter having spectrally selective transmission and disposed in the path of light transmitted through said second of said fiber pair. EXTRACT OF THE INVENTION Apparatus for analyzing fluids provided through a tube, comprising an analyzer instrument inside a container, a first connector coupled to the tube and having an end face, a second connector, which is coupled with the first connector and attached to the container, a pair of optical fibers disposed within the container, a first end of each of the fibers is mounted on the second connector, there is a clear optical path between the end face of each of the first ends of the fibers and at least one common point on the extreme face. A light source is optically coupled to the second end of a first of the fiber pair and an optical detector optically coupled to the second end of the second of said fiber pair.