Spectrometer with dynamically coded components

In an analytic spectrometer (50) having a central computer (9), permanently installed and exchangeable components (5), such as a radiation source, a detector, a beam splitter, a filter, external measurement probes and the like, each of which exhibiting a readable data carrier (7) with encoded data of parameters characterizing the respective component (5), the data media (7) can be written to and contains changeable time dependent data concerning the history and/or the actual properties of the corresponding component (5) for example length of operation, performance deterioration parameters or calibration curves of the component (5). These data can be continuously adjusted by the central computer (9) to the current state of the component (5) so that the data medium (7) connected to the component (5) can immediately supply information concerning the current actual properties of the component (5) when installing the component (5) in another spectrometer.

BACKGROUND OF THE INVENTION 
The invention concerns an analytic spectrometer in particular an infrared 
(IR) spectrometer with a central computer, permanently installed and 
exchangeable components such as a radiation source, a detector, a beam 
splitter, a filter, external measurement probes and the like, whereby the 
exchangeable components each exhibit a readable data medium with encoded 
data of parameters characterizing the respective optical component. 
A spectrometer of this kind is, for example, known from the article "FTIR 
Spectroscopy for the Analytical and Research Laboratory" by J. Sellors in 
the American journal "American Laboratory", April 1992, pages 23 through 
30. 
In the Fourier-transform infrared (FTIR) spectrometer described therein, 
which is principally utilized for research, a large number of 
software-controlled internal components are provided for which leads to an 
enormous number of possible permutations. In a system of this kind it is 
therefore important that each current configuration of system components 
be recognized in a manner which is as automatic as possible and 
communicated to the central computer. In order to automatically determine 
the type of at least those system components which are subject to exchange 
these components are equipped with a bar-code which with the assistance of 
bar-code reading instruments can be read-off from the corresponding 
component as information concerning the component type and transferred to 
the central computer. 
In addition information concerning the position of the corresponding 
component is transferred to the computer so that a system representation 
of the current spectrometer configuration can be reproduced in the memory 
of the central computer at any time and as a consequence decisions 
concerning the operation or the change of the spectrometer can be derived 
by means of the central computer. 
The known spectrometer further provides for a submemory allocation in the 
central memory in which special data concerning component types which are 
recognizable with the assistance of the bar-code can be stored. These 
types of data can, for example, be calibration curves characterizing the 
performance of the corresponding component type. In this fashion the 
central computer of the spectrometer is provided with the capability of 
reaching complicated decisions concerning the areas of applicability of 
the spectrometer, of determining possible incompatibilities or 
insufficiencies in the current configuration, and of demanding appropriate 
assistance. 
In addition to the bar-code, resistor networks or appropriately formed 
contact plugs can be utilized as data storage media for the respective 
exchangeable system components. In all spectrometers known to date, these 
data media contain however only very limited amount of information, namely 
the information concerning the type of the corresponding components and 
possibly their production date. All other important information concerning 
the component type, for example fundamental calibration curves or function 
diagrams have been up to this point stored in the normally plentiful 
memory of the central computer which is always part of a spectrometer. The 
information concerning the corresponding system components encoded onto 
the data medium was therefore, up to this time, exclusively passive and 
static and did not allow for a change in the stored data, for example, for 
the purpose of adjusting an individual current parameter value which 
characterizes the instantaneous state of the system component. 
When therefore in a known spectrometer, a component was exchanged with 
another component, it was necessary to usually first determine the 
individual properties of this component through measurements before the 
spectrometer could be rendered operational. This is particularly 
disadvantageous for system components which were removed from another 
spectrometer since individual data concerning the components which 
possibly had already been taken in the other spectrometer did not 
automatically move during the transfer of the component to the new 
installation location. Only in the event that the two spectrometers 
communicate with each other and are capable of exchanging data, stored in 
their central computers, concerning their system components can this 
problem occurring in conventional spectrometers be solved. Such a 
networking of spectrometers is, however, difficult and is normally not 
done. 
A further problem consists in the handling of exchange components which, 
for example, a customer of a spectrometer manufacturer receives as 
substitutes for defective components. In this situation the customer is 
interested in the particular data of the replacement component and the 
manufacturer is interested in the characteristic data known to the 
customer of the exchange component, which possibly can only be 
reconstructed with a certain degree of difficulty. In both cases it is 
only possible to supply this individual data concerning a spectrometer 
component in a manner which is separate from the component itself. 
It is therefore the purpose of the present invention to present an analytic 
spectrometer whose components can be utilized in a much more flexible 
fashion in various locations in equivalent spectrometers or in other 
spectrometers whereby the respective components, without any additional 
measures, such as measurements of characteristic properties of the 
component, can be installed in any arbitrary spectrometer and be 
immediately available for operation. 
SUMMARY OF THE INVENTION 
This purpose is achieved in accordance with the invention in that the data 
medium can be written to and contains changeable, time dependent data 
concerning the history and/or the current properties of the respective 
exchangeable components such as operation time, performance deterioration 
parameters or calibration curves of the components. In this fashion each 
exchangeable component in particular exchangeable components from the 
manufacturer or components which a user would like to take from one 
spectrometer and install in another, carry their own individual history in 
particular their calibration curves with them. In this fashion the 
spectrometer in which such an "intelligent" construction component is 
installed can be immediately placed into operation without the need for 
any additional measures. Even the utilization of components from another 
spectrometer is, in this fashion, greatly simplified. The corresponding 
exchangeable components can simply be installed in another spectrometer at 
an arbitrary point in time. Since all spectrometers are usually calibrated 
and, since at this time the components also carry the information 
concerning their individual calibration, there is a standardized interface 
between the spectrometer and the spectrometer components which allows for 
a permutation of all important components without additional difficulties. 
By way of example a user's defective spectrometer components can be 
directly replaced from stock without having to carry out difficult 
measurements of the component or having to effect a particular selection. 
In a preferred embodiment of the invention devices for reading the time 
dependent data of exchangeable components which is encoded on the data 
medium as well as devices for transferring these data to the central 
computer are provided for and a program for decoding these data and for 
making a decision on the basis of the current data is implemented in the 
central computer. In this fashion the central computer of the spectrometer 
can automatically record and evaluate the corresponding data. 
In an embodiment of the inventive spectrometer, appropriate devices, for 
example sensors, are provided for detecting changes in the data, 
corresponding to parameters of the exchangeable components, which are 
stored on one or more data media. 
In a particularly preferred improvement of this embodiment devices for 
transferring data signals to the central computer on the basis of detected 
changes of parameters as well as devices for writing on the data media of 
the exchangeable components are provided for. In this embodiment, a 
program for the processing of the incoming data signals is implemented in 
the central computer for controlling the devices for writing as well as 
for the automatic adjustment of changed parameter data of a component on 
its data media. In this fashion properties of the corresponding component 
which change during operation in the spectrometer can be stored in an 
automatic fashion on the data medium of the corresponding component in the 
form of appropriate current data. 
An embodiment is particularly preferred in which the inventive spectrometer 
is a Fourier transform infrared (FTIR) spectrometer. In other embodiments 
one could however be dealing with a nuclear magnetic residence (NMR), an 
electron spin residence (ESR), an ion cylotron residence (ICR) or a 
mass-spectrometer. 
Also within the framework of the present invention is an exchangeable, 
preferentially optical component of a spectrometer of the above mentioned 
kind with a readable data medium with encoded data of parameters 
characterizing the component in which the data medium can be written-to 
and which contains changeable, time-dependent data concerning the history 
and/or the current properties of the components, such as length of 
operation, performance deterioration parameters, or calibration curves of 
the component. 
An embodiment is thereby particularly advantageous with which data which 
cannot be changed is also stored on the data media of the component 
whereby this data should not, to the extent possible, be capable of being 
overwritten or deleted. Examples for this type of non-changeable data are 
the type of respective optical component and its date of manufacture. 
In an improvement of this embodiment, in addition to the manufacturing date 
of the component, critical points in time for the taking of new data for 
stored time-dependent data and/or for the checking and/or maintenance 
and/or an exchange of the components are also stored. In this fashion it 
is possible to issue pulses to the central computer of the spectrometer at 
the respective appropriate point in time which initiate an appropriate 
reaction of the system or a request for external changes. 
In a further preferred embodiment component data are stored on the data 
medium which correspond to parameters which characterize the differing 
interactions of the components with various spectrometers and/or other 
exchangeable components. This facilitates a particularly high flexibility 
when using such a dynamically coded component. 
In embodiments of the exchangeable optical component according to the 
invention, the data medium can be a chip, in particular, an EPROM or a 
Flash-ROM. In other embodiments the data medium is a magnetic memory. 
Although, the actual operation time of the components in accordance with 
the invention can be determined and stored with the assistance of a clock 
which is nearly always provided for in the central computer of the 
spectrometer, in a user-friendly embodiment of the components in 
accordance with the invention a clock which is preferentially connected to 
the data medium is provided for which automatically starts when the 
components enter into operation and stops when operation ceases to store 
the respective current length of operation of the component as the last 
value. 
Also within the framework of the current invention is, finally, a method 
for the operation of a spectrometer or of an exchangeable component of the 
above described kind with which, during the operation of the spectrometer, 
the data stored on the data medium corresponding to the current parameters 
of the exchangeable components in the spectrometer are automatically 
sampled by the central computer and in the event of a change of one or 
more parameters, appropriate new data are stored onto the data medium. 
The invention is more closely described and explained below in the 
embodiments represented in the drawing. The features which can be derived 
from the description and the drawing can find utilization in other 
embodiments of the invention either individually or collectively in 
arbitrary combination.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
In particular, FIG. 1 schematically shows a Fourier spectrometer 50 in 
accordance with the invention, whose general construction has become known 
by the company publication IFS 66 of the company Bruker Analytische 
Messtechnik GmbH. A radiation source 2, an interferometer 3 with movable 
mirrors 3a, 3b and a beam splitter 3c as well as two alternate detectors 
4a, 4b are integrated in or on a spectrometer housing 1, whereby a data 
medium 7 is schematically indicated in the drawing on the detector 4a. 
In internal operation, an initially divergent beam of light 10a, departing 
from the source 2, impinges on a concave mirror 11, to enter into the 
interferometer 3 as a parallel beam 10b via a planar mirror 12. The 
parallel light beam 10c exiting the interferometer 3 impinges via a 
focusing deflecting mirror 13 as converging light beam 10d into the sample 
region 6. A sample to be examined can be located at focus 10e. Following 
the focus the divergent light beam 10f leaves the sample region 6 and 
impinges via a further focusing mirror 14 onto the detector 4a. 
Alternatively one can switch onto the detector 4b via the focusing mirror 
16 by folding-in, sliding-in, in general, by moving-in the planar mirror 
15. 
Additional movable mirrors 22 through 25 are located in the optical path by 
means of which a light beam can be coupled in or out. In this fashion, 
with the assistance with the fixed mirror 21 and the movable mirror 22 it 
is possible to deflect a light beam 41a,b into the spectrometer housing 1 
via the entrance 41 from an external instead of the internal source. The 
double-arrowed symbol on the mirror is intended to indicate that, it can 
be tilted, displaced, or rotated to deflect the radiation beam. This 
transpires, in general, under computer control. If, for example, the 
mirror 22 is to be removed from the radiation beam 10b it is possible for 
the light leaving the internal source 2 to travel into the interferometer 
3. If the mirror 22 is moved-in, the light coming from the source 2 is 
blocked but that which is coming from an external source via entrance 41 
and mirror 21 gains entrance to the interferometer 3. In general the 
example shows, in addition to the entrance 41, 3 exits, 31-33 for 
deflecting-out the radiation beam 10c exiting the interferometer 3 which 
then merges into the exiting beam 31a, 32a or 33a to, by means of the 
mirror 23, 24 or 25, be introduced onto external samples. 
In the above described spectrometer 50 the radiation source 2, the beam 
splitter 3c as well as the detectors 4a and 4b are, for example, 
components which normally become used-up after a certain lifetime or 
utilization-time and must be replaced. These exchangeable spectrometer 
components, which are not shown in the drawing, could also be external 
light sources or probes with a measuring head and optical fibers which, 
for example, couple-in external light via the entrance 41 into the 
spectrometer 50. The external probes usually suffer a change in 
transmission during operation which is due to abrasion or scratching of 
the outer surface of the measuring head or to breakage of fibers the 
optical fiber bundle and the like. Filter elements, which are also not 
shown are included among those exchangeable components 7 whose lifetime is 
limited and therefore which are usually not permanently mounted into the 
spectrometer 50. 
In accordance with the present invention all or at least a part of these 
exchangeable, preferentially optical, components 5 for the spectrometer 50 
are provided with a writeable data medium 7 which contains the time 
dependent changeable data concerning the history and/or the current 
properties of the respective component 5 such as the operation time, 
certain performance deterioration parameters or calibration curves of the 
components. An exchangeable component 5 of this kind with a data media 7 
is, for example, the detector 4a shown in FIG. 1. 
Shown very schematically in FIG. 2 is the spectrometer 50 in which a 
component 5, intended to represent all other exchangeable components, 
exhibiting an attached data medium 7 is represented. By means of a read 
line 8a it is possible for the likewise only very schematically shown 
central computer 9 of the spectrometer 50 to read the data of the 
exchangeable component 5 which is stored on the data media 7. Via an 
additional data line, the write line 8b, it is possible for the central 
computer 9 to adjust the time changing data of the components 5 on the 
data media 7 to the actual state of the component 5, in that the 
appropriate old data is overwritten with the newer current data. 
Such an adjustment can take place either continuously, in regular 
intervals, or in irregular intervals based on corresponding signals from 
other parts of the spectrometer 50. The communication means which connect 
the central computer 9 to the spectrometer 50, are shown schematically in 
FIG. 2 as a read line 8a' and a write or command line 8b'. By means of 
these data lines it is possible for the central computer 9, for example, 
to also sample the current state of the components 5 on the basis of 
measurement values which are available to the spectrometer 50. On the 
basis of these sampled measurement values, by way of example calibration 
curves of the component 5, it is possible, for the central computer 9 to 
update the appropriate data on the data medium 7 via the write line 8b. 
In this fashion it is possible to always keep the data of the exchangeable 
components 5 on the data medium 7 current so that, for example, when 
utilizing the components 5 in another spectrometer, no preparatory 
measures such as calibration measurements and the like are necessary with 
respect to the component 5. The component now carries its own information 
about its history or its current state with it. In contrast to previous 
solutions in known spectrometers where this information was, at best, 
stored in the extensive memory of the central computer, an efficient 
interface for the element-specific data is realized. Thereby a 
re-recording of component-specific data from one central computer to 
another is unnecessary. 
Although the solution in accordance with the invention of a dynamic 
encoding of preferentially optical exchangeable components 5 of a 
spectrometer 50 appears more complicated and more expensive than the 
previous solution, a significant increase in flexibility of use of the 
exchangeable components is, however, achieved between different locations 
in, possibly, different spectrometers. In this fashion, for example, still 
operative exchangeable components of a defective spectrometer can be 
reused in another spectrometer without any additional preparatory 
measures. Also in the event components received by a customer of a 
spectrometer manufacturer as a new or rebuilt substitute component in 
exchange for a component which no longer functions in an acceptable 
fashion, the transfer of the component-specific information can take place 
automatically in both directions. 
The customer can install the exchange component immediately in his 
spectrometer and the manufacturer automatically receives the essential 
information concerning the current state of this component from the 
component sent back by the customer which normally substantially 
simplifies a repair. The exchangeable optical components 5 can also have 
non-changeable data stored on on their data medium 7, by way of example, 
their date of manufacture or their component type. Clearly, during use of 
the component 5, these data should neither be overwritten nor deleted. 
This type of "passive" data which are not subject to any time change, are 
already present with known spectrometers on the important exchangeable 
components, for example with the assistance of a bar-code labeling, a 
resistive network, or a corresponding contact plug. This passive encoding 
does not however allow for changes in data so that an updating of data 
concerning changeable parameters of the corresponding component was, up to 
now, not possible. All important changeable component data was, up to this 
point, solely stored in the central computer. 
Chips, in particular EPROMs or FLASH-ROMs can be utilized as data media 7 
for the recording of time dependent data of the exchangeable optical 
components 5. The data medium 7 can, however, also be a magnetic memory. 
In addition with particularly important and expensive components a clock 
which is preferentially connected to the data media 7 can be provided for 
which, during operation of the component 5 automatically starts and when 
operation ceases stops to record the respective current operation time of 
the component 5 as a final value. 
The invention is limited not only to IR-spectrometers of the above 
described type rather also includes all other kinds of conceivable 
spectrometer types for example NMR, ESR, ICR, or mass-spectrometers. 
Exchangeable components 5 with attached data media 7 in accordance with 
the invention can therefore for example also be used with radio frequency 
(HF) coils, probeheads, amplifiers, filters, power supplies, gradient 
generation systems or sample heaters.